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Final Programmatic Environmental Assessment of ASR Program

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Released: March 13, 2012
Final Programmatic
Environmental Assessment
for the Antenna Structure
Registration Program
Responsible Agency:
FEDERAL COMMUNICATIONS
COMMISSION
445 12th Street, SW
Washington, DC 20554
MARCH 13, 2012

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FINAL

PROGRAMMATIC ENVIRONMENTAL ASSESSMENT

FOR THE

ANTENNA STRUCTURE REGISTRATION PROGRAM

Responsible Agency:

Federal Communications Commission
445 12th Street, SW
Washington, DC 20554

Prepared by:

URS Group, Inc.
12420 Milestone Center Drive, Suite 150
Germantown, MD 20876

MARCH 13, 2012


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Table of Contents

ACRONYMS AND ABBREVIATIONS........................................................................................................... v

EXECUTIVE SUMMARY......................................................................................................................... ES-1

SECTION ONE


INTRODUCTION........................................................................................................1-1

1.1
Introduction ..............................................................................................1-1
1.2
Background...............................................................................................1-2
1.3
Regulatory Framework .............................................................................1-4
1.4
Proposed Action .......................................................................................1-6
1.5
Scope of the PEA......................................................................................1-6
1.6
Public Involvement...................................................................................1-7
1.6.1 Scoping Process............................................................................1-7
1.6.2 Draft PEA .....................................................................................1-7
1.6.3 Summary.......................................................................................1-8

SECTION TWO


PURPOSE AND NEED..............................................................................................2-1


2.1
Purpose .....................................................................................................2-1
2.2
Need..........................................................................................................2-1

SECTION THREE ALTERNATIVES........................................................................................................3-1


3.1
No Action Alternative ..............................................................................3-1
3.2
Alternative 1 – Existing ASR Program with FAA Lighting
Changes ....................................................................................................3-3
3.3
Alternative 2 – Modifications to The ASR Program................................3-4
3.3.1 Alternative 2 Option A – Require an EA for All Projects
Submitted for Registration Except for Certain Changes to
Existing Towers............................................................................3-5
3.3.2 Alternative 2 Option B – Limit which Projects Are
Categorically Excluded and Require an EA for the Rest .............3-6
3.3.3 Alternative 2 Option C – Make Permanent the Interim
Requirement to Prepare an EA for All Projects More Than
450 feet in Height but Otherwise Do Not Change the
Categorical Exclusion...................................................................3-8
3.4
Alternatives Considered And Dismissed................................................3-10
3.4.1 Prohibit All New Tower Construction .......................................3-10
3.4.2 Prohibit Towers That Exceed a Certain Height..........................3-10
3.4.3 Prohibit Towers in Certain Locations.........................................3-10
3.4.4 Prohibit Guy Wires on New Towers ..........................................3-10

SECTION FOUR


AFFECTED ENVIRONMENT.....................................................................................4-1


4.1
Introduction ..............................................................................................4-1
4.2
Existing Communications Towers ...........................................................4-1
4.2.1 General Characteristics.................................................................4-1
4.2.2 Number of Existing Towers .........................................................4-2
4.2.3 Distribution of Existing Towers ...................................................4-3
4.2.4 Future Needs/Trends ....................................................................4-3

4.3
Resources Not Affected............................................................................4-4
i

Table of Contents
4.3.1 Geology ........................................................................................4-4
4.3.2 Soils ..............................................................................................4-4
4.3.3 Farmlands .....................................................................................4-4
4.3.4 Groundwater .................................................................................4-5
4.3.5 Coastal Zones/Coastal Barriers ....................................................4-5
4.3.6 Designated Wilderness Areas.......................................................4-5
4.3.7 Air Quality....................................................................................4-6
4.3.8 Noise.............................................................................................4-6
4.3.9 Land Use.......................................................................................4-6

4.4
Water Resources .......................................................................................4-6
4.4.1 Surface Water ...............................................................................4-7
4.4.2 Wetlands and Waters of the United States ...................................4-7

4.5
Floodplains ...............................................................................................4-9
4.6
Biological Resources ................................................................................4-9
4.6.1 Vegetation and Wildlife..............................................................4-10
4.6.2 T&E Species/Critical Habitat .....................................................4-10
4.6.3 Migratory Birds ..........................................................................4-11
4.6.3.1 Data Limitations and Uncertainty ...............................4-12
4.6.3.2 Migratory Bird Abundance..........................................4-13
4.6.3.3 Land Birds – Breeding.................................................4-13
4.6.3.4 Land Birds – Wintering ...............................................4-17
4.6.3.5 Waterfowl – Breeding .................................................4-17
4.6.3.6 Waterfowl – Wintering................................................4-18
4.6.3.7 Migratory Bird Geographic Patterns ...........................4-18
4.6.3.8 Migratory Bird Flight Altitudes...................................4-20
4.6.3.9 Timing of Migration ....................................................4-21
4.6.3.10 Avian Mortality from Communications Towers .........4-21
4.6.3.11 Other Sources of Avian Mortality ...............................4-23
4.6.4 Bald and Golden Eagles .............................................................4-25
4.7
Cultural Resources..................................................................................4-26
4.8
Other Visual and Aesthetic Resources ...................................................4-27
4.9
Economics ..............................................................................................4-27
4.10
Radio Frequency Radiation ....................................................................4-28

SECTION FIVE


ENVIRONMENTAL CONSEQUENCES.....................................................................5-1


5.1
Categories of Impacts ...............................................................................5-1
5.2
Significance of Impacts ............................................................................5-1
5.2.1 Context .........................................................................................5-2
5.2.2 Intensity ........................................................................................5-2
5.2.3 Significance Determination ..........................................................5-3
5.3
Assumptions .............................................................................................5-4
5.3.1 Tower Construction Footprints.....................................................5-4
5.3.2 Number of Towers........................................................................5-4
5.3.3 Tower Location.............................................................................5-4
5.3.4 Tower Height................................................................................5-5
5.3.5 Support System.............................................................................5-5
5.3.6 Lighting Scheme...........................................................................5-5

ii

Table of Contents
5.4
Impacts by Resource.................................................................................5-6
5.4.1 Water Resources ...........................................................................5-6

5.4.1.1 Surface Water ................................................................5-6
5.4.1.2 Wetlands and Waters of the United States ....................5-7
5.4.2 Floodplains ...................................................................................5-8
5.4.3 Biological Resources ....................................................................5-8

5.4.3.1 Vegetation and Wildlife (Other than T&E
Species/Critical Habitat and Migratory Birds) ..............5-8
5.4.3.2 T&E Species and Critical Habitat ...............................5-10
5.4.3.3 Migratory Birds ...........................................................5-11
5.4.3.4 Bald and Golden Eagles ..............................................5-24
5.4.4 Cultural Resources......................................................................5-26
5.4.5 Other Visual and Aesthetic Resources .......................................5-27
5.4.6 Economics ..................................................................................5-28
5.4.7 Radio Frequency Radiation ........................................................5-30

SECTION SIX


CUMULATIVE IMPACTS...........................................................................................6-1


6.1
Introduction ..............................................................................................6-1
6.2
Past, Present, and Reasonably Foreseeable Projects and Actions
Considered ................................................................................................6-2
6.3
Geographic Extent and Time Frame.........................................................6-2
6.4
Cumulative Impacts to Migratory Birds...................................................6-2
6.4.1 Impacts from Existing Towers .....................................................6-3
6.4.2 Impacts from New Registered Towers .........................................6-3
6.4.3 Effects from Climate Change .......................................................6-4
6.4.4 Impacts from Other Sources .........................................................6-4

6.5
Summary...................................................................................................6-6

SECTION SEVEN FINDINGS..................................................................................................................7-1


7.1
Overview ..................................................................................................7-1
7.2
Consequences of the No Action Alternative ............................................7-2
7.3
Consequences of Alternative 1 .................................................................7-3
7.4
Consequences of Alternative 2 Option A .................................................7-3
7.5
Consequences of Alternative 2 Option B .................................................7-4
7.6
Consequences of Alternative 2 Option C .................................................7-5
7.7
Cumulative Impacts..................................................................................7-6
7.8
Summary...................................................................................................7-7

SECTION EIGHT


MITIGATION..............................................................................................................8-1


8.1
Overview ..................................................................................................8-1
8.2
Mitigation Arising From the EA Process for Individual Towers .............8-1
8.3
Additional Mitigating Measure by the FCC .............................................8-2
8.4
Additional Recommendations for Applicants ..........................................8-2

SECTION NINE


PUBLIC COMMENTS ON DRAFT PEA ....................................................................9-1


9.1
Overview ..................................................................................................9-1
9.2
Summary of Comments Received and BUREAU Responses..................9-1
iii

Table of Contents
9.2.1 Chapter 1 – Introduction...............................................................9-2
9.2.2 Chapter 2 – Purpose and Need .....................................................9-2
9.2.3 Chapter 3 – Alternatives ...............................................................9-2
9.2.4 Chapter 4 – Affected Environment...............................................9-4
9.2.5 Chapter 5 – Environmental Consequences...................................9-5
9.2.6 Chapter 6 – Cumulative Impacts ..................................................9-9
9.2.7 Chapter 7 - Findings ...................................................................9-10
9.2.8 Chapter 8 – Mitigation................................................................9-10
9.2.9 Chapter 11 – References.............................................................9-10

SECTION TEN


LIST OF PREPARERS ............................................................................................10-1


SECTION ELEVEN REFERENCES.........................................................................................................11-1


List of Appendices

Appendix A
Agencies, Organizations, and Individuals Consulted During the NEPA Process
Appendix B
Avian/Tower Collision Literature Summary

List of Figures

Figure 1: NEPA Flow Chart No Action Alternative .................................................................................3-2
Figure 2: NEPA Flow Chart Alternative 1................................................................................................3-3
Figure 3: NEPA Flow Chart Alternative 2 Option A................................................................................3-5
Figure 4: NEPA Flow Chart Alternative 2 Option B................................................................................3-7
Figure 5: NEPA Flow Chart Alternative 2 Option C................................................................................3-9
Figure 6: Tower Types..............................................................................................................................4-2
Figure 7: Bird Conservation Regions of the United States .....................................................................4-15
Figure 8: General Depiction of North American Avian Migratory Flyways ..........................................4-19
Figure 9: Migratory Flight Altitudes for Various Bird Groups...............................................................4-21
Figure 10: Mean Annual Bird Mortality and Tower Heights..................................................................5-13
Figure 11: Mean Annual Bird Mortality and Tower Heights (<600 feet)...............................................5-13
Figure 12: Bird Mortality and Guy Wire Sets.........................................................................................5-15
Figure 13: Projected Future Bird Mortality ............................................................................................5-20
Figure 14: Summary of Annual Avian Mortality by Source.....................................................................6-5

List of Tables

Table 1: Summary of Impacts by Resource for All Alternatives...............................................................11
Table 2: Number of Bird Species Listed by Lead USFWS Region ........................................................4-11
Table 3: Population Estimates of Land Birds by State............................................................................4-14
Table 4: Bird Conservation Regions Population Estimates ....................................................................4-16
Table 5: Recent Christmas Bird Count Data for the United States.........................................................4-17
Table 6: Sources and Estimates of Annual Avian Mortality in the United States (in millions)..............4-24
iv

Acronyms and Abbreviations
AGL
Above Ground Level
T&E
Threatened & Endangered
ASR
Antenna Structure Registration
THPO
Tribal Historic Preservation Office
BCC
Bird of Conservation Concern
BCR
Bird Conservation Region
USACE
U.S. Army Corps of Engineers
BGEPA
Bald and Golden Eagle Protection
U.S.C.
U.S. Code
Act
USFWS
U.S. Fish and Wildlife Service
CEQ
Council on Environmental Quality
WHSRN
Western Hemisphere Shorebird
CFR
Code of Federal Regulations
Reserve Network
CWA
Clean Water Act
WOUS
Waters of the United States
DAS
Distributed Antenna System
EA
Environmental Assessment
EIS
Environmental Impact Statement
EO
Executive Order
EPA
Environmental Protection Agency
ESA
Endangered Species Act
FAA
Federal Aviation Administration
FCC
Federal Communications
Commission
FEMA
Federal Emergency Management
Agency
FIRM
Flood Insurance Rate Map
FONSI
Finding of No Significant Impact
MBTA
Migratory Bird Treaty Act
MHz
megahertz
MOA
Memorandum of Agreement
MPE
Maximum Permissible Exposure
NEPA
National Environmental Policy Act
NHPA
National Historic Preservation Act
NPA
Nationwide Programmatic
Agreement
NPDES
National Pollutant Discharge
Elimination System
NRHP
National Register of Historic Places
PEA
Programmatic Environmental
Assessment
PEIS
Programmatic Environmental Impact
Statement
PIF
Partners In Flight
PL
Public Law
RF
Radio Frequency
SHPO
State Historic Preservation Office
v

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Executive Summary

INTRODUCTION

This Programmatic Environmental Assessment (PEA) has been prepared to evaluate the environmental
impacts of the Antenna Structure Registration (ASR) Program administered by the Federal
Communications Commission (FCC or the Commission). The ASR Program is the process under which
each antenna structure that requires Federal Aviation Administration (FAA) notification must be
registered with the FCC by its owner. The ASR requirements only apply to those antenna structures that
may create a hazard to air navigation due to height (generally, structures more than 200 feet [61 meters]
tall) or proximity to an airport runway. The current ASR Program does not routinely require an applicant
to prepare an EA to evaluate potential impacts to migratory birds.
The U.S. Court of Appeals for the District of Columbia Circuit in American Bird Conservancy, Inc. v.
FCC
(2008) determined that the FCC has not adequately evaluated the potential effects that its current
ASR program has on threatened and endangered species and migratory birds. The court further stated that
the Commission could begin its evaluation of these effects with a PEA. In addition, the court required the
Commission to provide notice of pending ASR applications that would ensure meaningful public
involvement in the agency’s National Environmental Policy Act (NEPA) procedures.
In partial response to the court’s decision, the FCC has adopted procedures designed to help ensure that
the environmental effects of proposed communications towers, including their effects on migratory birds,
are fully considered prior to construction. The procedures were adopted on December 6, 2011, and will
become effective following approval by the U.S. Office of Management and Budget. The procedures
require:
·
Applicants for new tower registration to provide a 30-day opportunity for public comment on the
environmental effects of the proposed construction; and
·
On an interim basis, pending completion of the PEA and subsequent rulemaking, preparation of
an Environmental Assessment (EA) for a proposed tower more than 450 feet (137 meters) in
height to address its potential impact on migratory birds (FCC 2011b).
This PEA is adopted by the FCC’s Wireless Telecommunications Bureau (Bureau) pursuant to delegated
authority under the FCC’s rules.

PROPOSED ACTION

The Proposed Action is to modify the ASR Program and associated NEPA compliance procedures as
necessary to ensure compliance with NEPA and other applicable environmental laws, and in so doing to
reduce the program’s impacts on migratory birds to an extent consistent with achieving the program’s
purposes and with the Commission’s authority under the Communications Act. This PEA reviews the
existing ASR Program and NEPA compliance procedures to evaluate their effects on migratory birds and
other environmental resources, in compliance with the 2008 court decision. Because of the nature of the
projects under the ASR Program and in response to the 2008 court decision, this PEA primarily focuses
on potential impacts to migratory birds.

PURPOSE AND NEED FOR THE ACTION

The ASR Program promotes air safety by requiring the registration of antenna structures that may create a
hazard to air navigation due to their height or proximity to an airport runway. The purposes of the
Proposed Action are to ensure that the ASR program complies with NEPA and applicable environmental
regulations, and to reduce its impacts on migratory birds to an extent consistent with the Commission’s
mandate and authority under the Communications Act. In order to achieve these purposes, this PEA
examines how potential environmental impacts are evaluated as part of the ASR Program and associated
NEPA review and documentation.
ES-1

Executive Summary

ALTERNATIVES

The alternatives considered include a No Action Alternative, Alternative 1 that assumes a change in the
FAA’s permitted lighting configurations, and three options of Alternative 2 that require greater
consideration of the effects of proposed towers on migratory birds and other environmental resources than
the No Action Alternative.
The No Action Alternative, Alternative 1, and Alternative 2 each include the public notice and comment
procedures that the Commission adopted on December 6, 2011 (FCC 2011b). Alternative 2 Option C
assumes that the interim requirement to prepare an EA for proposed towers that are more than 450 feet
(137 meters) in height will become permanent.
It should be noted that lighting on new towers must conform to the requirements of the current FAA
Advisory Circular 70/7460-1K Obstruction Marking and Lighting (USDOT/FAA 2007). The FCC cannot
require lighting schemes that are not in compliance with this circular. Currently the FAA does not allow
lighting configurations that use red flashing lights without also requiring the presence of red steady-
burning lights. Following its anticipated publication of the results of a conspicuity study, the FAA may
revise its circular to allow lighting schemes that use red flashing lights without red steady-burning lights.

No Action Alternative

The No Action Alternative is defined as continuation of the existing ASR Program and NEPA compliance
procedures, including the public notice and 30-day public comment requirement, under the existing FAA-
permitted lighting configurations.

Alternative 1 – Existing ASR Program with FAA Lighting Changes

Alternative 1 is the continuation of the existing ASR Program and NEPA compliance procedures,
including the public notice and 30-day public comment requirement, along with the potential changes to
the FAA’s permitted lighting configurations under which future towers that use red flashing lights would
not also have red steady-burning lights.

Alternative 2 – Modifications to the ASR Program

Under Alternative 2, the FCC would revise its NEPA compliance procedures for the ASR Program to
require more comprehensive assessments of potential environmental impacts from new towers and tower
modifications involving a substantial increase in size, particularly for potential effects to migratory birds.
Alternative 2 would not change the procedures for tower modifications or replacements that do not
involve a substantial increase in size, for certain lighting changes, or for minor ASR actions, including
administrative changes, changes in ownership, dismantling of towers, and minor changes/corrections to
existing towers. It also would not affect activity at registered towers that does not require action in the
ASR system, such as tower repair and replacement of tower parts.
There are three options under Alternative 2 for determining the level of NEPA review that would be
required for a project.

Alternative 2 Option A


Alternative 2 Option A would require an EA for all new registered towers outside of an antenna farm,
regardless of height, use of guy wires, or lighting scheme. As defined by FCC rules, an antenna farm is
an area in which similar antenna towers are clustered. Towers in an antenna farm, replacement towers,
and modifications of existing towers would require an EA if they involve a substantial increase in size
over the existing tower or towers. An EA would also be required for changes to existing towers
involving: (1) a change to steady-burning lighting; (2) a change to high-intensity white lighting in a
residentially zoned neighborhood; (3) addition of lighting; or (4) human exposure to levels of radio
frequency (RF) radiation in excess of the limits in 47 CFR §§ 1.1310 and 2.1093. Every EA would need
ES-2

Executive Summary
to consider, in addition to other potential environmental effects, the effects that the project would have on
migratory birds and Bald and Golden Eagles.
Under Option A, the only projects that would be categorically excluded from preparation of an EA would
be those that propose: (1) a change from red steady-burning to flashing lights or removal of lighting on an
existing tower (depending upon potential revisions to the FAA lighting circular); (2) replacement or
modification of an existing tower that involves no substantial increase in size; (3) construction in an
antenna farm that does not involve a substantial increase in size over existing towers; or (4) a minor
action.

Alternative 2 Option B


Under Alternative 2 Option B, a proposed new tower would require preparation of an EA only under
certain combinations of location and structural and lighting features. Any proposed new registered tower
that requires an EA under the existing rules would require an EA. Also, if a new tower would be
constructed in an important eagle use area, the applicant would have to coordinate with USFWS in
preparing a site-specific EA. If a qualified biologist determines that no Bald or Golden Eagles are or may
be present in the vicinity of a proposed tower, the applicant could presume that the site is not in an
important eagle use area. If Bald or Golden Eagles may be present, the applicant would have to consult
with USFWS to determine whether the site is in an important eagle use area.
Other locational features for which a project may require an EA would include ridgelines, coastal zones,
and bird staging areas, colonial nesting sites, or Western Hemisphere Shorebird Reserve Network
(WHSRN) sites. If any of those locational features are present, and a tower would be more than 450 feet
(137 meters) tall, would use a red steady-burning lighting scheme, or would use guy wires, an EA would
be required. Towers that are not proposed within any of these locations or that do not have any of these
structural or lighting features would continue to be categorically excluded, unless they would require an
EA under the existing rules or would be located in an important eagle use area.
Towers in an antenna farm, replacement towers, and modifications to existing towers would require an
EA under the same circumstances as new towers if they involve a substantial increase in size. An
addition of red steady-burning lights to an existing tower would also require an EA if the tower is located
on a ridgeline or in a coastal zone, bird staging area, colonial nesting site, or WHSRN site.
Every EA would need to consider, in addition to other potential environmental effects, the effects that the
project would have on migratory birds and Bald and Golden Eagles. If the tower is in a wetland or
floodplain and is over 450 feet (137 meters) tall, uses red steady lights, or uses guy wires, the FCC would
expect the applicant to either provide evidence that it is not in a riparian zone or a detailed analysis of its
effects on migratory birds.

Alternative 2 Option C


Under Alternative 2 Option C, in addition to those towers for which an EA is required under the existing
FCC rules, an EA would be required for any proposed new tower, or replacement or modification of an
existing tower that involves a substantial increase in size, that is more than 450 feet (137 meters) above
ground level (AGL), regardless of location, lighting scheme, or use of guy wires. Option C assumes that
the interim measure of the FCC’s recently adopted procedures will become a permanent requirement.
Towers less than or equal to 450 feet (137 meters) AGL would be categorically excluded from
preparation of an EA unless a condition requiring an EA under the existing program is present.
Every EA would need to consider, in addition to other potential environmental effects, the effects that the
project would have on migratory birds and Bald and Golden Eagles.
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Executive Summary

Alternatives Considered and Dismissed

Various alternatives for changes to the ASR Program were examined but dismissed as not feasible in light
of the need to meet service requirements, technological constraints, and safety considerations. These
alternatives include prohibiting all new tower construction; prohibiting all towers that exceed a certain
height; prohibiting all towers in certain locations; and prohibiting guy wires on all new towers.

ENVIRONMENTAL CONSEQUENCES

The ASR program is national in scope, and the environmental impacts of each individual tower may vary
greatly depending on local conditions. Therefore, this PEA does not assess the environmental impacts of
any particular tower. Rather, the PEA focuses on the broad, programmatic impacts of the ASR program
in a national context. In addition, the PEA considers whether the FCC’s processes, including its criteria
for determining which towers are categorically excluded and which require an EA, ensure that potentially
significant impacts of individual towers will be identified and considered. If an individual tower may
have potentially significant environmental impacts, those impacts would be addressed in a site-specific
EA prepared for that tower.
Impacts (or effects) can be categorized by description (beneficial or adverse), context (site-specific, local,
regional, or national), intensity (negligible, minor, moderate, or major), and duration (short- or long-
term). NEPA requires consideration of all categories of impacts that apply to a proposed action, including
direct, indirect, and cumulative impacts. According to the Council on Environmental Quality (CEQ)
regulations (40 CFR Section 1508.27), assessment of an impact’s significance under NEPA requires
consideration of both its context and its intensity.
For purposes of evaluating the impacts of the ASR program as a whole, as addressed in this PEA, the
relevant context is generally national or international in scope. In project-specific EAs, the discussion of
impacts would be more local in context.
Intensity refers to the severity of impact. This PEA uses impact threshold definitions that take into
consideration the characteristics of communications towers:
·
Negligible – The impact is barely perceptible or measurable and remains localized and confined.
·
Minor – The impact is slight but perceptible and measurable and remains localized and confined.
·
Moderate – The impact is readily apparent and sufficient to cause a change in the character-
defining features of a resource. It generally does not affect the resource’s viability.
·
Major – The impact results in a substantial and highly noticeable change in character-defining
features or involves an individually important feature of a resource. A major impact may, but
does not necessarily, affect the resource’s viability.
The intensity of the ASR Program’s impacts to various resources is summarized in Table 1 at the end of
this Executive Summary.
Once the relevant context has been identified and an impact has been determined to be negligible, minor,
moderate, or major, a determination of the impact’s significance must be made. Three levels of impact
can be identified:
·
No Impact – No impact is anticipated.
·
No Significant Impact – An impact is anticipated, but the impact does not meet the
intensity/context significance criteria for the specified resource.
·
Significant Impact – An impact is anticipated that meets the intensity/context significance criteria
for the specified resource.
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Executive Summary
Negligible, minor, and moderate impacts are generally not significant. However, a moderate impact may
be significant if its importance is magnified by the context in which it occurs. Major impacts are often
significant, but are not necessarily so when considered in context.
Several resources were determined to not be affected by or to be affected negligibly by the No Action
Alternative, Alternative 1, and the three options under Alternative 2. These resources include: geology,
soils, farmlands, groundwater, coastal zones/barriers, designated wilderness areas (which are already
protected under FCC rules), air quality, noise, and land use. However, because coastal zones and barriers
contain important habitats for migratory birds, these resources are addressed as part of the discussion of
impacts to migratory birds.

CUMULATIVE IMPACTS

In assessing cumulative impacts upon a resource, the incremental impacts of the action in question are
considered together with the impacts of other past, present, and reasonably foreseeable future actions, as
well as existing conditions. The No Action Alternative, Alternative 1, and all options of Alternative 2
will result in negligible, minor, or moderate adverse impacts to all resources addressed in this PEA,
except for migratory birds. The Bureau concludes that the negligible, minor, and moderate impacts of the
ASR Program on resources other than migratory birds, when viewed in the context of all impacts on each
resource, are not cumulatively significant.
Under the No Action Alternative, Alternative 1, or any option of Alternative 2, towers regulated under the
ASR Program will continue to affect migratory birds. Migratory bird deaths due to collisions with
communications towers are currently estimated at 6.6 million per year, and, depending on the alternative
considered, this number is expected to be between 4.9 million and 8.6 million in 2022.
While communications towers contribute to the overall adverse impacts of all human activities on bird
populations, communications tower collisions are only responsible for approximately 0.3 percent of the
more than 2 billion annual bird deaths that currently occur due to cat predation and anthropogenic
sources. In addition, these deaths occur against a backdrop of high natural mortality to migrating birds
due to a number of factors. Indeed, communications tower collisions annually kill approximately 0.07
percent of the total migratory bird population (6.6 million out of 10 billion). Although the absolute
number of birds killed at communications towers is large, towers are a relatively minor contributor to
total human-caused avian mortality, and the impact of these deaths is likely even smaller when considered
in the context of high natural mortality.

FINDINGS

Environmental impacts from towers are dependent on a variety of factors including location, height,
structural support system, and lighting scheme. The principal adverse impact of communications towers
is on birds, especially migratory birds, and tower lighting is the primary contributor to bird mortality from
towers. Based on a review of the available peer-reviewed literature and the analysis contained in this
PEA, the relative severity of impacts on birds is as follows:
·
All other factors being equal, taller towers result in higher levels of avian mortality than shorter
towers.
·
All other factors being equal, towers with guy wires result in higher levels of avian mortality than
towers without guy wires.
·
All other factors being equal, steady-burning lights on towers result in higher levels of avian
mortality than flashing lights.
Under all alternatives, the environmental impacts of the ASR Program at the national level on resources
other than migratory birds are negligible, minor, or moderate. Taking into consideration the context and
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Executive Summary
intensity of each of these impacts, the Bureau finds that none of them rises to the level of significance.
Furthermore, the existing ASR Program and all program alternatives require EAs for towers when
existing ASR program criteria are triggered, including when the processing Bureau determines that an
otherwise categorically excluded action may have a significant environmental impact. These
requirements ensure that potentially significant local effects on environmental resources other than
migratory birds will be identified and considered.

No Action Alternative

The No Action Alternative would have no significant adverse environmental impacts at the national level
to any resources, including migratory birds, although there could be significant impacts to migratory
birds, Bald Eagles, or Golden Eagles at the local level that would not be addressed. At the national level,
major adverse impacts on migratory birds due to construction in areas of heavy migration use (coastal
zones, ridgelines, bird staging areas/colonial nesting sites, WHSRN sites, and riparian zones) would
continue. Avian mortality due to bird collisions with communications towers would be expected to
increase in proportion to the number and types of new towers that are constructed. Current annual avian
mortality from existing communications towers is estimated at approximately 6.6 million birds, the
majority of which are migratory birds. Assuming that approximately 2,800 new towers would be
constructed annually under the existing ASR Program, avian mortality would increase to an estimated 8.6
million birds by the year 2022 due to collisions with communications towers. While this number is large
and constitutes a major impact, it is only 0.07 percent of the overall U.S. bird population, which is
estimated at 10 billion birds. Furthermore, when evaluated in context with other sources of avian
mortality, towers cause approximately 0.3 percent of annual avian mortality attributable to human sources
and cat predation. Thus, in the national context of overall migratory bird abundance and other, greater
forces to which migratory birds are subject, the relative impact of communications towers is small. In
addition, the available scientific information does not support a finding that tower collisions may have a
significant impact on any particular species. Therefore, the impact to migratory birds under the No Action
Alternative is not significant.
In a local context, site-specific EAs are required when existing ASR program criteria are triggered.
Migratory bird habitat features (ridgelines, coastal zones, bird staging areas, colonial nesting sites,
WHSRN sites, and riparian zones) and tower features (height, lighting scheme, and guy wires) which may
pose a greater risk of harm to migratory birds, as well location in important Bald and Golden Eagle use
areas, are not routinely considered under the current program in determining whether an EA is required.
Therefore, there may be instances in which potentially significant impacts to a local population of
migratory birds, Bald Eagles, or Golden Eagles would not be addressed.

Alternative 1 – Existing ASR Program with FAA Lighting Changes

Under Alternative 1 there would be no significant adverse environmental impacts at the national level to
any resources, including migratory birds, although there could be significant impacts to migratory birds,
Bald Eagles, or Golden Eagles at the local level that would not be addressed. Major adverse impacts on
migratory birds due to construction in areas of heavy migration use (coastal zones, ridgelines, bird staging
areas, colonial nesting sites, WHSRN sites, and riparian zones) would continue. Avian mortality due to
bird collisions with communications towers would increase in proportion to the number and types of new
towers that are constructed. However, the increase in avian mortality due to new tower construction
would be greatly reduced by the potential FAA lighting circular revisions. Under these revisions, future
towers that use red flashing lights would not also have steady-burning lights. A tower without red steady-
burning lights is estimated to result in 50 to 70 percent less avian mortality than if it uses red steady-
burning lights (Gehring et al. 2009). Therefore, bird mortality would decrease under this alternative when
compared to future conditions under the No Action Alternative. In addition, tower owners would have an
economic incentive to voluntarily change (or extinguish) red steady-burning lights on existing towers and
use flashing lights exclusively in order to reduce energy and maintenance costs, thereby further reducing
ES-6

Executive Summary
migratory bird mortality. Therefore, under Alternative 1, the impact to migratory birds at the national
level is not significant.
In the local context, as is the case with the No Action Alternative, site-specific NEPA documents would
be required under Alternative 1 when existing ASR program criteria are triggered. Migratory bird habitat
features (ridgelines, coastal zones, bird staging areas, colonial nesting sites, WHSRN sites, and riparian
zones) and tower features (height, lighting scheme, and guy wires) which may pose a greater risk of harm
to migratory birds, as well as location in important Bald and Golden Eagle use areas, are not routinely
considered under the current program in determining whether an EA is required. Therefore, there may be
instances in which potentially significant impacts to a local population of migratory birds, Bald Eagles, or
Golden Eagles would not be addressed.

Alternative 2 – Modifications to the ASR Program

Alternative 2 Option A


Alternative 2 Option A would have no significant adverse environmental impacts at either the national or
local level to any resources, including migratory birds. Major adverse impacts to migratory birds would
continue and avian mortality due to bird collisions with communications towers would be expected to
increase in proportion to the number and types of towers that are constructed.
With no revisions to the FAA lighting circular, potential impacts to migratory birds at the national level
would be reduced to a limited extent when compared with the No Action Alternative because of
mitigation measures that would result from the EA process. Therefore, the impact to migratory birds is
not significant at the national level for the same reasons as discussed under the No Action Alternative.
Under Option A with potential revisions to the FAA lighting circular, as under Alternative 1, the increase
in avian mortality due to new tower construction would be greatly reduced because future towers that use
red flashing lights would not also have red steady-burning lights. In addition, tower owners would have
an economic incentive to voluntarily change (or extinguish) red-steady burning lights on existing towers
and use flashing lights exclusively in order to reduce energy and maintenance costs, thereby further
reducing migratory bird mortality. Potential impacts to migratory birds would be further reduced to a
limited extent when compared with Alternative 1 because of mitigation measures that would result from
the EA process.
Therefore, under Option A, with or without revisions to the FAA lighting circular, the impact to
migratory birds at the national level is not significant.
In the local context, with or without revisions to the FAA lighting circular, under Option A the
preparation of site-specific EAs for all new tower construction would include an evaluation of the
potential effects on migratory birds and Bald and Golden Eagles. This evaluation would ensure that
potentially significant environmental impacts from an individual tower on migratory birds and Bald and
Golden Eagles would be addressed at the local level.

Alternative 2 Option B


Under Alternative 2 Option B, there would be no significant adverse environmental impacts at either the
national or the local level to any resources, including migratory birds. Major adverse impacts to
migratory birds would continue and avian mortality due to bird collisions with communications towers
would be expected to increase in proportion to the number and types of towers that are constructed.
Without revisions to the FAA lighting circular, impacts to migratory birds at the national level would be
reduced slightly compared to the No Action Alternative, to an extent at least comparable to Option A.
Under Option B, applicants would have an incentive to avoid siting towers that are over 450 feet (137
meters) tall, use red steady-burning lights, or use guy wires; and that are located on ridgelines, in coastal
zones, in bird staging areas, in colonial nesting sites, in WHSRN sites, or in riparian zones within
ES-7

Executive Summary
wetlands and floodplains. Therefore, towers with the features that pose the greatest risk of harm to
migratory birds would be less likely to be constructed in the locations where migratory birds are most
prevalent. Applicants would also likely attempt to avoid constructing any towers in important eagle use
areas. In addition, potential impacts to migratory birds and Bald and Golden Eagles may be reduced
when compared with the No Action Alternative because of mitigation measures that would result from the
EA process. Therefore, the impact to migratory birds under Option B without revisions to the FAA
lighting circular is not significant at the national level.
With potential revisions to the FAA lighting circular, as under Alternative 1, impacts to migratory birds
would be greatly reduced compared to the No Action Alternative because future towers that use red
flashing lights would not also have steady-burning lights. A tower without red steady-burning lights is
estimated to cause 50 to 70 percent less avian mortality than if it uses red steady-burning lights. In
addition, tower owners would have an economic incentive to voluntarily change (or extinguish) red
steady-burning lights on existing towers and use flashing lights exclusively in order to reduce energy and
maintenance costs, thereby further reducing migratory bird mortality. Avian mortality would be further
slightly reduced because the Bureau anticipates that applicants would likely attempt to avoid constructing
towers that are more than 450 feet (137 meters) tall or use guy wires in areas important to migratory birds,
and to avoid constructing any towers in important Bald and Golden Eagle use areas. Overall, migratory
bird mortality would be less than under Alternative 1 and comparable to Option A with revisions to the
FAA lighting circular. Therefore, under Option B with revisions to the FAA lighting circular, the impact
to migratory birds is not significant at the national level.
In the local context, with or without revisions to the FAA lighting circular, EAs would be required under
Option B for towers with the features that contribute the most to migratory bird deaths if they are located
in the areas where migratory birds are most prevalent. These EAs would include an evaluation of
potential impacts to individual species of migratory birds to the extent that species-specific information
exists. In addition, EAs would be required for all towers in important Bald and Golden Eagle use areas.
These requirements would ensure that potentially significant environmental effects on migratory birds and
Bald and Golden Eagles at the local level would be addressed.

Alternative 2 Option C


Under Alternative 2 Option C, there would be no significant adverse environmental impacts at the
national level to any resources, including migratory birds, although there could be significant impacts to
migratory birds, Bald Eagles, or Golden Eagles at the local level that would not be addressed. Major
adverse impacts on migratory birds due to construction in areas of heavy migration use (coastal zones,
ridgelines, bird staging areas, colonial nesting sites, and WHSRN sites) would continue. Avian mortality
due to bird collisions with communications towers would be expected to increase in proportion to the
number and types of towers that are constructed.
Without revisions to the FAA lighting circular, avian mortality at the national level would be reduced
compared to the No Action Alternative because applicants would have an incentive to avoid constructing
towers over 450 feet (137 meters) tall to the extent practicable. However, in many instances it is unlikely,
particularly for broadcast towers, that such a tower could be reduced appreciably in height and still be
able to meet service coverage requirements. Because Options A and B would require EAs for more
towers that may affect migratory birds, Option C would not reduce potential impacts to migratory birds as
much as those two options. However, potential impacts to migratory birds may be reduced when
compared with the No Action Alternative because of mitigation measures that would come out of the EA
process for towers more than 450 feet (137 meters) tall. Therefore, the impact to migratory birds is not
significant at the national level for the same reasons as discussed under the No Action Alternative.
Under Option C, with the potential revisions to the FAA lighting circular, as under Alternative 1, impacts
to migratory birds would be greatly reduced compared to the No Action Alternative because future towers
that use red flashing lights would not also have steady-burning lights. A tower without red steady-
ES-8

Executive Summary
burning lights is estimated to cause 50 to 70 percent less avian mortality than if it uses red steady-burning
lights. Tower owners would also have an economic incentive to voluntarily change (or extinguish) red-
steady burning lights on existing towers and use flashing lights exclusively in order to reduce energy and
maintenance costs, thereby further reducing migratory bird mortality. Avian mortality would be further
slightly reduced because applicants would have an incentive to avoid constructing towers over 450 feet
(137 meters) tall where feasible, and because of mitigation measures that may come out of the EA process
for towers more than 450 feet (137 meters) tall. Overall, the reduction in migratory bird deaths would be
more than under Alternative 1, but less than under Option A or Option B with revisions to the FAA
circular. Therefore, under Option C with revisions to the FAA lighting circular, the impact to migratory
birds is not significant at the national level.
In the local context, with or without revisions to the FAA circular, site-specific NEPA documents would
be required under Option C when existing ASR program criteria are triggered or when a proposed tower
would be more than 450 feet (137 meters) tall. Except for tower height, migratory bird habitat features
(ridgelines, coastal zones, bird staging areas, colonial nesting sites, and WHSRN sites) and tower features
(lighting scheme and guy wires) which pose a greater risk of harm to migratory birds, as well as location
in important Bald and Golden Eagle use areas, would not be routinely considered under the Option C in
determining whether an EA is required. Therefore, there may be instances in which potentially
significant impacts to a local population of migratory birds, Bald Eagles, or Golden Eagles would not be
addressed.

Cumulative Impacts

For several reasons, the Bureau concludes that the additional migratory bird deaths caused by
communications towers are not cumulatively significant at the national level. First, the estimated 6.6
million annual bird deaths caused by communications towers constitute only approximately 0.3 percent of
the total bird deaths attributable to anthropogenic sources and cat predation. Thus, the incremental
mortality that these deaths add to the total avian mortality attributable to human actions is relatively not
large. In addition, these deaths occur against a backdrop of high natural mortality to migrating birds due
to a number of factors. Indeed, annual avian deaths attributable to towers constitute approximately 0.07
percent of the migratory bird population. Taking all these factors together, the incremental impact of the
ASR Program on migratory birds, considered in context and together with the impacts of other past,
present, and reasonably foreseeable future actions, is not cumulatively significant nationally.

Summary

The impacts of the ASR Program at the national level on all resources, including migratory birds, are not
significant. However, depending on the alternative selected, there may be instances in which potentially
significant impacts to a local population of migratory birds, Bald Eagles, or Golden Eagles would not be
addressed.
At the national level, the best available and most current estimate of avian mortality, primarily to
migratory birds, from collisions with communications towers is 6.6 million birds annually. Tall towers,
steady-burning lights, and guy wires are the primary tower characteristics contributing to avian mortality.
Migratory bird mortality from all sources would be expected to increase in the future, with an anticipated
increase in the number of vertical structures in the environment as well as continuing impacts from other
actions and factors. The construction of new communications towers would contribute incrementally to
this future increase in mortality, regardless of whether FAA lighting changes are implemented.
The Bureau recognizes that the potential changes to the FAA lighting circular would have the greatest
beneficial effect and would be the critical element in reducing impacts to migratory birds under any of the
alternatives. Under Alternative 1 (which assumes FAA lighting changes will occur) and any of the options
under Alternative 2 (if FAA lighting changes occur), the incremental increase in migratory bird mortality
from new towers approved under the ASR Program would be substantially reduced due to the use on
ES-9

Executive Summary
future towers of red flashing lights exclusively without red steady-burning lights. Studies indicate that the
use of flashing lights on towers may reduce bird mortality at towers by 50 to 70 percent (Gehring et al.
2009). In addition, voluntary lighting changes on existing towers from steady-burning to flashing lights
would further reduce migratory bird impacts and may possibly reduce the total number of bird deaths
from registered towers to below current levels.
The Bureau acknowledges that the estimated bird mortality as a result of collisions with towers approved
under its ASR Program is a large number. However, the anticipated annual bird mortality from existing
and future communications towers under any alternative is not significant at the national level, whether
considered as a separate, direct impact or as part of a cumulative analysis.
At the site-specific level, under Options A and B of Alternative 2, the requirements to prepare EAs for
individual towers would ensure that potentially significant effects on local migratory bird and Bald and
Golden Eagle populations would be considered. Under the No Action Alternative, Alternative 1, and
Option C of Alternative 2, potentially significant impacts on local migratory bird and Bald and Golden
Eagle populations may not be addressed.
Very little reliable information is available with regard to species-specific impacts as a result of tower
collisions. While information on species-specific effects would be relevant to the analysis presented in
this PEA, it would be infeasible and unreasonably costly for the FCC to generate such data. Effects of
individual towers on threatened and endangered species are considered under the FCC’s existing
procedures. To the extent that evidence exists regarding the effects of individual towers on other avian
species, such evidence will be considered in EAs where required under any Option of Alternative 2, and
may be raised through the FCC’s notice process.

MITIGATION

Under the No Action Alternative, Alternative 1, and all options of Alternative 2, the FCC could require
mitigation of potentially significant environmental effects through the preparation and review of EAs for
individual towers. The FCC is also engaged in programmatic consultation with the U.S. Fish and
Wildlife Service (USFWS) to consider potential further measures to protect threatened and endangered
(T&E) species. The Bureau encourages tower owners and applicants to consider additional measures that
may further mitigate any environmental effects.
Table 1 summarizes impacts by resource for the No Action Alternative, Alternative 1, and Alternative 2
Options A, B, and C.
ES-10

Executive Summary

Table 1: Summary of Impacts by Resource for All Alternatives

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

Surface Water

Short- and long-term Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.
negligible to minor
adverse impacts
from increases in
sedimentation and
impervious surface
area and minor
modifications of
stream channels due
to construction
activities. Fuel
spill/leak from
backup generator
during site operation
may result in short-
term negligible to
minor adverse
impacts.

Wetlands/

Short- and long-term Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.

Waters of the U.S.

negligible to minor
adverse impacts
from increases in
sedimentation and
impervious surface
area and potential
wetland fill or
disturbance due to
construction
activities.
ES-11

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

Floodplains

Short- and long-term Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.
negligible to minor
adverse impacts due
to the potential for
construction
activities to increase
floodwater flows
downstream of the
project site.

Vegetation and

Short- and long-term Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.

Wildlife

negligible to minor
(other than T&E
adverse impacts due
Species/Critical
to vegetation
Habitat and
disturbance/removal,
Migratory Birds)
some direct
mortality to less
mobile wildlife,
habitat
fragmentation, and
introduction of non-
native invasive
species.

T&E Species/

Short- to long-term Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.

Critical Habitat

negligible to minor
adverse impacts
because FCC’s
procedures for
implementing the
Endangered Species
Act (ESA) ensure
that adverse effects
to T&E species will
be avoided or
mitigated.
ES-12

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

Migratory Birds

Direct:

Short- to

Direct:

Short- to

Direct (without

Direct (without

Direct (without

long-term major
long-term major
revisions to FAA
revisions to FAA
revisions to FAA
adverse impact.
adverse impact.
lighting circular):
lighting circular):
lighting circular):
Annual bird
Mortality from new Short- to long-term
Short- to long-term
Short- to long-term
mortality expected
towers would
major adverse
major adverse
major adverse
to increase from
decrease by 50 to 70 impact. Mortality
impact. Reduction in impact. Annual bird
approximately 6.6
percent as a result of expected to decrease annual bird mortality mortality expected to
million currently to revisions to the FAA somewhat compared compared to No
decrease compared to
approximately 8.6
lighting circular
to No Action.
Action because of
No Action, but not as
million in the year
when compared to
Review of EAs
incentives to place
much as with Option
2022, based on an
No Action, based on expected to lead to
new towers that are A (which requires
estimated 2,800 new an estimated 2,800
adoption of
over 450 feet tall, use more EAs) or Option
towers built
new towers built
mitigating measures red steady lights, or B (which provides
annually.
annually. This
in some cases and
use guy wires outside incentives to place
decrease alone would applicants would
of coastal zones,
new towers that are

Indirect:

Short- to reduce total bird
have incentive to
ridgelines, bird
over 450 feet tall, use
long-term minor
mortality from
make changes to
staging areas,
red steady lights, or
impacts (habitat and existing and new
existing towers rather colonial nesting sites, use guy wires away
site abandonment). towers from
than construct new
WHSRN sites, and
from resources
Evidence does not
approximately 8.6
towers. However, in riparian zones within important to
support
million to
many instances the
wetlands and
migratory birds, and
determination of RF approximately 7.2
factors contributing floodplains, as well to reduce tower
radiation impacts.
million to 7.6 million to migratory bird
as to reduce the
heights and avoid
in the year 2022.
deaths would likely heights of the tallest red-steady lights and
be difficult to avoid. towers and avoid use guy wires within
In addition, assuming
of red steady-burning these areas if
owners of 50 percent

Direct (with

lights and guy wires feasible). Applicants
of existing towers
revisions to FAA
within these areas
would have an
extinguish red
lighting circular):
where feasible.
incentive to reduce
steady-burning lights Short- to long-term
Reduction would be heights of new
or change them to red major adverse
limited by
towers, where
flashing lights (and
impact. Mortality
applicants’ ability to feasible, and review
that these towers are expected to decrease avoid these areas and of EAs for towers
evenly distributed
slightly compared to features, as well as greater than 450 feet
across tower heights), Alternative 1.
ES-13

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

annual bird mortality Review of EAs
protection already
(137 meters) is
from existing towers expected to lead to
provided under FCC expected to lead to
would be reduced by adoption of
rules for areas that
adoption of
an estimated 25 to 35 mitigating measures overlap (e.g.,
mitigating measures
percent. This would in some cases and
floodplains and
in some cases.
reduce total bird
applicants would
wetlands). Moving a However,
mortality from
have incentive to
tower off of a
opportunities for
existing and new
make changes to
ridgeline may require significant reductions
towers from 6.6
existing towers rather a taller tower or
in height are very
million currently to
than construct new
multiple towers,
limited.
between 4.9 million towers. However, in which may cause

Direct (with

and 5.9 million in the many instances the
other environmental revisions to FAA
year 2022.
factors contributing impacts that offset
lighting circular):
to migratory bird
the potential

Indirect:

Similar to
Short- to long-term
deaths would likely beneficial impact to
No Action.
major impact.
be difficult to avoid, birds. Some use of
Reduction in annual
particularly since
white flashing lights bird mortality
steady lighting would instead of red steady- expected to be more
no longer be a factor. burning lighting may than under
occur, provided local

Indirect (with or

Alternative 1, but not
land use regulations
without revisions to
as much as under
allow it. Overall, by

FAA lighting


Option A (because
establishing clear
circular): Somewhat
fewer EAs would be
guidelines and
reduced impacts
prepared) or Option
aligning tower
(habitat and site
B (which provides
owners’ economic
abandonment)
incentives to place
incentives with the
compared to No
new towers that are
protection of
Action due to case-
over 450 feet tall or
migratory birds,
by-case review of
use guy wires away
reduction in bird
EAs. Evidence does
from resources
mortality expected to
not support
important to
be at least
determination of RF
migratory birds, and
comparable to
radiation impacts.
to reduce tower
Option A.
heights and avoid
ES-14

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

Direct (with

guy wires within
revisions to FAA
these areas if
lighting circular):
feasible). Applicants
Short- to long-term
would have an
major adverse
incentive to reduce
impact. Reduction in heights of new
annual bird mortality towers, where
compared to
feasible, and review
Alternative 1 because of EAs for towers
of incentives to place greater than 450 feet
new towers that are (137 meters) is
over 450 feet tall or expected to lead to
use guy wires outside adoption of
of coastal zones,
mitigating measures
ridgelines, bird
in some cases.
staging areas,
However,
colonial nesting sites, opportunities for
WHSRN sites, and
significant reductions
riparian zones within in height are very
wetlands and
limited.
floodplains, as well

Indirect (with or

as to reduce the
without revisions to
heights of the tallest

FAA lighting


towers and avoid guy circular): Slightly
wires within these
less impact (habitat
areas where feasible. and site
Reduction would be abandonment) than
limited by
No Action, due to
applicants’ ability to case-by-case review
avoid these areas and of EAs for towers
features, as well as
more than 450 feet
protection already
(137 meters) tall, but
provided under FCC reduction would be
rules for areas that
less than under
ES-15

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

overlap (e.g.
Option A or B.
floodplains and
Evidence does not
wetlands). Moving a support
tower off of a
determination of RF
ridgeline may require radiation impacts.
a taller tower or
multiple towers,
which may cause
other environmental
impacts that offset
potential beneficial
impact to birds.
Overall, by
establishing clear
guidelines and
aligning tower
owners’ economic
incentives with
protection of
migratory birds,
reduction in bird
mortality expected to
be at least
comparable to
Option A.

Indirect (with or
without revisions to
FAA lighting
circular

): Slightly
less impact (habitat
and site
abandonment) than
No Action, but less
reduction in impact
ES-16

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

than Option A.
Evidence does not
support
determination of RF
radiation impacts.

Bald/Golden

Short-term minor to Similar to No Action. Short-term minor
Short-term minor
Short-minor to

Eagles

moderate adverse
adverse impacts due adverse impacts due moderate adverse
impacts due to tower
to tower construction to tower construction impacts due to tower
construction and
and operation
and operation
construction and
operation
disturbances to eagle disturbances to eagle operation
disturbances to eagle
breeding, nesting,
breeding, nesting,
disturbances to eagle
breeding, nesting,
and feeding
and feeding
breeding, nesting,
and feeding
activities. Impacts
activities. Impacts
and feeding
activities.
expected to be minor expected to be minor activities. There may
because preparation because of incentives be a slight reduction
and review of EAs
to place new towers in impact compared
would require
outside of important to No Action and
coordination with
eagle use areas, in
Alternative 1 due to
USFWS, which
addition to
preparation and
would likely
preparation and
review of EAs for
recommend actions review of EAs for
towers more than 450
to reduce impacts to towers to be located feet (137 meters)
Bald and Golden
in such areas. EAs
AGL and incentive to
Eagles.
would require
construct shorter
coordination with
towers, which may
USFWS, which
not be as attractive to
would likely
nesting Bald Eagles,
recommend actions depending on other
to reduce impacts to site characteristics.
Bald and Golden
Eagles. Reduction in
impacts likely to be
at least comparable
to Option A.
ES-17

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

Cultural

Short- and long-
Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.

Resources

term, negligible to
minor impacts
anticipated based on
Nationwide
Programmatic
Agreement (NPA).

Other Visual and

Short- and long-
Similar to No Action. Similar to No Action. Similar to No Action. Similar to No Action.

Aesthetic

term, minor to

Resources

moderate adverse
impacts due to
presence of new
towers and lighting
in landscape.

Economics

Short- to long-term Similar to No Action. Short- to long-term
Short- to long-term
Short- to long-term
minor adverse
moderate adverse
minor adverse
minor adverse
impact on applicants
impacts on applicants impacts on applicants impacts on applicants
due to cost and
due to increased
due to increased
due to increased
schedule
costs for applicants
costs for applicants
costs for applicants
requirements for
to prepare an
to prepare an
to prepare an
applicants to prepare
estimated 2,800 EAs estimated 235 to 276 estimated 165 EAs
and FCC to review
annually.
EAs annually.
annually.
an estimated 100
Construction of
Construction of
Construction of
EAs annually.
towers may be
towers may be
towers may be
delayed by the time delayed by the time delayed by the time
necessary for
necessary for
necessary for
applicants to prepare applicants to prepare applicants to prepare
and FCC to review
and FCC to review
and FCC to review
2,800 EAs a year, to 235 to 276 EAs a
165 EAs a year, to
the extent these tasks year, to the extent
the extent these tasks
cannot be completed these tasks cannot be cannot be completed
concurrently with
completed
concurrently with
other pre-
concurrently with
other pre-
construction
other pre-
construction
ES-18

Executive Summary

No Action

Alternative 2

Alternative 2

Alternative 2

Resource

Alternative 1

Alternative

Option A

Option B

Option C

activities. To
construction
activities. FCC
maintain current
activities. To
would require
processing timelines, maintain current
additional staff time
FCC would need to processing timelines, to review/process
reallocate staff from FCC would need to those EAs, which
existing duties to
reallocate staff from may result in a minor
review/process EAs existing duties to
increase in
or obtain funds to
review/process EAs processing time.
hire more staff;
or obtain funds to
otherwise, there
hire more staff;
would be extensive
otherwise, there
delays in EA
could be delays in
processing times.
EA processing times.

RF Radiation

No impact
No impact
No impact
No impact
No impact
(human exposure) anticipated.
anticipated.
anticipated.
anticipated.
anticipated.
ES-19

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Introduction

SECTION ONE

INTRODUCTION

1.1 INTRODUCTION
This Programmatic Environmental Assessment (PEA) has been prepared to evaluate the potential
environmental impacts of the Antenna Structure Registration (ASR) Program administered by the Federal
Communications Commission (FCC or the Commission).
The ASR Program is the process under which each antenna structure that requires Federal Aviation
Administration (FAA) notification must be registered with the FCC by its owner. The ASR requirements
only apply to those antenna structures that may create a hazard to air navigation due to height (generally,
structures more than 200 feet [61 meters] tall) or proximity to an airport runway. The current ASR
Program does not routinely require an applicant to prepare an EA to evaluate potential impacts to
migratory birds.
The U.S. Court of Appeals for the District of Columbia Circuit in American Bird Conservancy, Inc. v.
FCC
(2008) determined that the FCC has not adequately evaluated the potential effects that its current
ASR program has on threatened and endangered species and migratory birds. This court decision stated
that in order for the FCC to comply with its obligations under the National Environmental Policy Act of
1969, as amended (NEPA), and the Endangered Species Act of 1973 (ESA), the Commission must
consider whether the potential significant environmental impacts from the ASR program require
preparation of a Programmatic Environmental Impact Statement (PEIS), as well as reconsider whether
potential effects on threatened and endangered species require programmatic consultation with the U.S.
Fish and Wildlife Service (USFWS) under the ESA. The court further stated that the Commission could
begin this evaluation with a PEA. In addition, the court required the Commission to provide notice of
ASR applications that would ensure meaningful public involvement in NEPA review.
In partial response to the court’s decision, the FCC has adopted procedures designed to help ensure that
the environmental effects of proposed communications towers, including their effects on migratory birds,
are fully considered prior to construction. The procedures were adopted on December 6, 2011, and will
become effective following approval by the U.S. Office of Management and Budget. The procedures
require:
·
Applicants for new tower registration to provide a 30-day opportunity for public comment on the
environmental effects of the proposed construction. This allows agencies and the public a
meaningful opportunity to raise site-specific and species-specific concerns; and
·
On an interim basis, pending completion of this PEA and subsequent rulemaking, preparation of
an Environmental Assessment (EA) for a proposed tower more than 450 feet (137 meters) in
height to address its potential impact on migratory birds (FCC 2011b).
This PEA has been prepared in accordance with NEPA, the Council on Environmental Quality (CEQ)
regulations for implementing NEPA (40 CFR 1500–1508), and the FCC regulations for implementing
NEPA (47 CFR 1.1301-1.1319). This PEA will also serve as a means to address the FCC’s obligations
under other Federal statutes, including the ESA.
The scope of this PEA includes an evaluation of the range of potential environmental impacts associated
with towers requiring registration under the FCC’s ASR Program. Because of the nature of the projects
under the ASR Program and in response to the 2008 court decision, this PEA primarily focuses on
potential impacts to migratory birds.
This PEA is adopted by the FCC’s Wireless Telecommunications Bureau (Bureau) pursuant to delegated
authority under the FCC’s rules. All findings and recommendations in this PEA are those of the Bureau.
1-1

Introduction
1.2 BACKGROUND
The FCC was established by the Communications Act of 1934 and is charged with regulating interstate
and international communications by radio, television, wire, satellite, and cable. The FCC's jurisdiction
includes the 50 states, the District of Columbia, and all U.S. possessions.
The ASR program was instituted by the FCC in 1995 and is the process by which any antenna structure
more than 200 feet (61 meters) above ground level (AGL) and certain antenna structures located within
the landing slope of an airport runway, as defined under the FAA’s rules, must be registered with the
FCC. (The FCC’s online calculator TOWAIR may be used to help determine whether an antenna
structure requires registration.) The ASR system includes existing antenna structures that meet the
criteria for registration as well as newly proposed towers. The tower owner is responsible for registering
the antenna structure and for maintaining any required painting and/or lighting. As of February 1, 2012,
there were 96,039 structures classified as towers, poles, or masts identified as having a construction date
in the FCC ASR database (FCC 2012). This number does not include antennas that are placed on
buildings, bridges, water towers, and other structures.
Communications towers serve various industries and agencies, including radio, television, cellular phone,
paging, microwave, public safety communications (such as police/fire dispatch), and national defense, as
well as other advanced and emerging services. National defense and other systems operated by Federal
agencies are not licensed by the FCC, and their towers are not required to be registered unless they are
also used for FCC-licensed services.
Although new communications antennas can often be collocated on existing towers or other structures
such as buildings, in many instances the deployment of services requires construction of a new tower.
Several factors, such as construction costs, government regulations, the availability of a willing
landowner, and the engineering requirements of a service provider, can influence the decision whether to
collocate a new communications antenna on an existing structure or construct a new tower.
Designs of communications towers may differ. For instance, communications towers may be supported
by guy wires or can be self-supporting, depending on various engineering, economic, environmental, or
historic preservation factors. A guyed tower is a straight tower supported by guy wires to the ground,
which anchor the tower. Self-supporting tower styles include monopoles (single tube towers with one
foundation) and lattice towers (typically three-sided with a triangular base). Communications towers
range widely in height, with many less than 200 feet (61 meters) above ground level (AGL), others over
1,000 feet (305 meters) AGL, and various heights in between. Typically the tallest communications
towers are guyed, but there are guyed towers at almost any tower height.
The Commission and the FAA each have statutory responsibilities related to ensuring that antenna
structures do not present a hazard to air safety. Specifically, Section 303(q) of the Communications Act of
1934, as amended, authorizes the Commission to prescribe painting and/or illumination of an antenna
structure when there is a “reasonable possibility” that it may cause a hazard to air navigation, and requires
permittees, licensees, and tower owners to maintain such lighting and/or illumination. Section 1501 of the
Federal Aviation Act authorizes the FAA to require that persons proposing to erect a structure provide
notice to the FAA when such notice will promote air safety. Under current rules, each tower owner
proposing to construct or alter an antenna structure that is more than 200 feet (61 meters) AGL, or that
may interfere with the approach or departure space of a nearby airport runway, must notify the FAA of
the proposed construction and subsequently register the tower with the Commission’s ASR Program.
As part of its review, the FAA considers whether the proposed structure constitutes a potential hazard,
and may recommend appropriate painting and lighting for the structure. Current FAA guidelines
ordinarily require lighting for communications towers over 200 feet (61 meters) tall, as well as for some
towers in the approach or departure space of a nearby runway. Such lighting must conform to one of the
six FAA Lighting Styles for communications towers. While some of these FAA Lighting Styles rely
1-2

Introduction
solely on white flashing lights, all styles that use red flashing lights also use red steady-burning lights.
The FAA is completing a conspicuity study that specifically addresses the use of red flashing lights
instead of red steady-burning lights. Based on the results of that study, the FAA may revise its lighting
circular to allow lighting schemes that use red flashing lights without red steady-burning lights.
In a Report and Order released November 30, 1995, the Commission adopted rules implementing the
ASR Program and began requiring antenna structure owners (instead of licensees) to register antenna
structures with the Commission. The towers registered in ASR include towers constructed prior to the
1995 Report and Order that meet the criteria for registration as well as those constructed since. In a
Memorandum Opinion and Order on Reconsideration released March 8, 2000, the Commission clarified
several registration requirements. In a Notice of Proposed Rulemaking released April 20, 2010, the
Commission sought comment on proposed procedural and other changes to the ASR process.
The number of towers constructed annually increased dramatically beginning in the early 1980s through
about the year 2000 (FCC 2012). Since 2000, the annual number of registered towers constructed has
decreased, but still remains at levels above those in the early 1990s.

Court Cases and Related FCC Proceedings

In the Migratory Bird Notice of Inquiry (NOI) released in August of 2003 (WT Docket No. 03-187,
Effects of Communications Towers on Migratory Birds), the Commission launched an inquiry regarding
the impact that collisions with communications towers may have on migratory birds. The NOI requested
information supported by scientific evidence on a number of topics in three general categories:
·
the number of migratory bird collisions with communications towers;
·
the role that certain factors such as lighting, height and type of antenna structure, weather, tower
location, and bird migration paths might play in such collisions; and,
·
the effectiveness of any measures to mitigate migratory bird collisions with communications
towers.
Based on the record developed in response to the NOI, the Commission stated that it would consider
whether further action was warranted, including possible amendments of the environmental rules.
To assist the Commission in evaluating the quality and sufficiency of the existing research, FCC hired an
environmental consulting firm, Avatar Environmental LLC (Avatar). After Avatar furnished a report with
its findings and recommendations (Avatar et al. 2004), the FCC’s Wireless Telecommunications Bureau
issued a Public Notice seeking comments and reply comments in response to the report’s findings.
In its Notice of Proposed Rulemaking in November of 2006, the FCC sought comments on whether the
Commission should take measures to reduce the number of instances in which migratory birds collide
with communications towers.
In American Bird Conservancy, Inc. v. FCC (2008), the U.S. Court of Appeals for the District of
Columbia Circuit determined that the FCC has not adequately evaluated the potential effects that its
current ASR program has on threatened and endangered (T&E) species and migratory birds. The court
decision held that in order for the FCC to comply with its obligations under NEPA and the ESA, the
Commission must consider whether the potential significant environmental impacts from the ASR
program require preparation of a PEIS. The court stated that the Commission could begin this evaluation
with a PEA. The court also instructed the FCC to reconsider whether potential effects on threatened and
endangered species require programmatic consultation with the USFWS under the ESA. In addition, the
court required the Commission to provide notice of ASR applications that would ensure meaningful
public involvement in NEPA review.
On May 2, 2008, a group of trade associations filed a Petition for Expedited Rulemaking regarding how
the Commission should provide pre-approval public notice and opportunity for comment as required
1-3

Introduction
under American Bird Conservancy, Inc. v. FCC. The FCC then opened Docket No. WT 08-61 (National
Environmental Policy Act Compliance for Proposed Tower Registrations) to address the court’s decision.
The FCC sought comment on the trade associations’ petition.
On April 29, 2009, the Bureau issued a Public Notice seeking comments on a petition for expedited
rulemaking and other relief filed on April 14, 2009, by the American Bird Conservancy, Defenders of
Wildlife, and National Audubon Society. The petitioners requested that the Commission adopt on an
expedited basis new rules that they assert are necessary to comply with NEPA, ESA, the Migratory Bird
Treaty Act (MBTA), and the FCC’s implementing regulations, and to carry out the court’s mandate in
American Bird Conservancy, Inc. v. FCC.
On December 6, 2011, after the Bureau sought public comment on draft rules, the Commission adopted
an Order requiring the following:
·
Applicants for new tower registration must provide a 30-day opportunity for public comment on
the environmental effects of the proposed construction so that interested parties may have a
meaningful opportunity to raise site-specific concerns; and
·
On an interim basis, pending completion of this PEA and subsequent rulemaking, an applicant
must prepare an EA for a proposed tower more than 450 feet (137 meters) in height to address its
potential impact on migratory birds. (FCC 2011b)
1.3 REGULATORY FRAMEWORK
This PEA has been prepared in accordance with NEPA, CEQ regulations for implementing NEPA (40
CFR 1500-1508), and FCC regulations for implementing NEPA (47 CFR 1.1301-1.1319). CEQ
regulations mandate that all Federal agencies use a systematic interdisciplinary approach to environmental
planning and the evaluation of actions that might significantly affect the human environment. According
to Section 1508.14 of the CEQ regulations, "human environment" shall be interpreted comprehensively to
include the natural and physical environment and the relationship of people with that environment. A
determination of “significance” according to Section 1508.27 of the CEQ regulations requires
consideration of both context and intensity.
The significance of an action must be analyzed in several contexts such as society as a whole (human,
national), the affected region, the affected interests, and the locality. Significance varies with the setting
of the proposed action and both short- and long-term effects are relevant.
Intensity refers to the severity of impact and includes: consideration of both beneficial and adverse
impacts; effects on public health or safety; unique characteristics of the geographic area; the degree to
which impacts are likely to be highly controversial, highly uncertain, or involve unique or unknown risks;
the degree to which the action may establish a precedent for future actions with significant effects or
represents a decision in principle about a future consideration; whether the action is related to other
actions with individually insignificant but cumulatively significant impacts; the degree to which the
action may adversely affect cultural resources protected by the National Historic Preservation Act
(NHPA) or T&E species protected by the ESA; and whether the action would violate a Federal, state, or
local law that protects the environment.
The intent of NEPA is to protect, restore, or enhance the human environment through well-informed
Federal decisions. This PEA evaluates the environmental effects of the ongoing ASR Program (the No
Action Alternative) and several alternatives.
NEPA requires consideration be given to all aspects of the human environment through a systematic,
interdisciplinary approach to agency decision-making (PL 91-190 42 U.S.C. § 4332). This
interdisciplinary approach ensures balanced consideration of various resources. The review of actions
under an array of other Federal environmental statutes can also be incorporated into the NEPA process.
1-4

Introduction
Much of the research, planning, and consultation that occur under these other laws can take place at the
same time that the evaluation and assessment is done for the NEPA document, thus avoiding duplicate
data collection and analysis. It is highly recommended, and in some cases required, to document
compliance with other Federal laws and Executive Orders (EOs) in the NEPA document.
This PEA addresses the FCC’s obligations under these other Federal environmental statutes. Although the
FCC as an independent agency is not subject to most EOs, in some instances the FCC considers the
effects on the subjects of EOs as part of its evaluation of effects on the human environment under NEPA
(e.g., floodplains as set forth in EO 11988 and wetlands as set forth in EO 11990). Where useful to
provide better understanding, key provisions of relevant statutes and EOs are discussed in more detail in
the text of the PEA.
Under Section 7 of the ESA, as amended (U.S.C. 1531-1544), Federal agencies, in consultation with the
USFWS or the National Marine Fisheries Service (NMFS), are required to evaluate the effects of their
actions on special status species of fish, wildlife, and plants, and their habitats, and to take steps to
conserve and protect these species. Special status species are defined as plants or animals that are
candidates for, proposed as, or listed as sensitive, threatened, or endangered by USFWS or NMFS.
Because towers registered under the ASR Program are not located in marine environments, this PEA
discusses ESA matters only in terms of those species regulated by the USFWS.
The MBTA (16 U.S.C. 703-712) was enacted to ensure the protection of shared migratory bird resources.
A migratory bird is any species that lives, reproduces, or migrates within or across international borders at
some point during its annual life cycle. The MBTA prohibits the take and possession of any migratory
bird, its eggs, or nests, except as authorized by a valid permit or license. Courts have rendered differing
decisions regarding the scope of the MBTA’s application to Federal agencies, as well as whether a party
may be liable under the MBTA for the unintentional, incidental death of a migratory bird.
EO 13186, Protection of Migratory Birds, directs Federal agencies whose activities have or are likely to
have a measurable, negative effect on migratory bird populations to develop and implement a
Memorandum of Understanding with USFWS to promote the conservation of migratory birds.
The FCC has not yet resolved the nature and scope of its responsibilities, if any, under the MBTA, and as
an independent agency, the FCC is not subject to the terms of EO 13186. However, because migratory
birds are part of the human environment that is considered under NEPA, they are addressed in this PEA.
Under the current ASR program, tower registration applications are categorically excluded from the
requirement to prepare an EA unless the proposed facility:
·
Would be located in an officially designated wilderness area or wildlife preserve.
·
May affect listed T&E species or designated critical habitat, or is likely to jeopardize the
continued existence of proposed T&E species or result in destruction or adverse modification of
proposed critical habitat.
·
May affect resources listed or eligible for listing in the National Register of Historic Places
(NRHP) or Native American religious and cultural sites.
·
Would be located in a floodplain.
·
Would involve significant changes in surface features (e.g., wetland fill, deforestation, or water
diversion).
·
Would be equipped with high intensity white lights and located in a residentially zoned
neighborhood.
·
Would cause human exposure to levels of RF radiation in excess of limits established in 47 CFR
§§1.1310 and 2.1093.
1-5

Introduction
In these cases, the applicant must prepare an EA that includes sufficient analysis to support a
determination that the proposed tower would or would not have a significant environmental impact.
The FCC will also require an EA if the processing Bureau, in response to a petition, on its own motion, or
in response to comments from the public and/or other agencies submitted during the 30-day period for
comment under the FCC’s new notice procedures, determines that an otherwise categorically excluded
action may have a significant environmental impact. The FCC’s new notice procedures provide for
public notice and a 30-day opportunity for public comment on the environmental effects of the proposed
construction. Under these procedures, the applicant is not permitted to certify that the project is
categorically excluded until after the FCC has confirmed that it has identified no reason to require an EA
in light of any comments it has received.
1.4 PROPOSED ACTION
The Proposed Action is to modify the ASR Program and associated NEPA compliance procedures as
necessary to ensure compliance with NEPA and other applicable environmental laws, and in so doing to
reduce the program’s impacts on migratory birds to the extent consistent with achieving the program’s
purposes and with the Commission’s authority under the Communications Act. This PEA reviews the
existing ASR Program and NEPA compliance procedures to evaluate their effects on migratory birds and
other environmental resources, in compliance with the 2008 court decision.
1.5 SCOPE OF THE PEA
CEQ regulations (40 CFR §§ 1500.4(i), 1502.4, and 1502.20) encourage the development of program-
level NEPA documents to focus on the issues specific to a proposed action. This PEA will also address
other environmental regulations by providing a framework for assessing impacts of proposed future,
individual projects.
A programmatic environmental document, such as this PEA, is prepared when an agency is proposing to
carry out a broad action, program, or policy. The existing ASR Program, which the court ordered the FCC
to review, is a broad action with nationwide implications. The programmatic approach creates a
comprehensive, global analytical framework that assesses impacts expected from the program (or changes
to the program) as a whole. It also supports subsequent environmental evaluations, such as stand-alone,
site-specific EAs that may be required to determine the nature and extent of impacts resulting from
individual towers at specific locations. It also allows the FCC to identify those project types that are
unlikely to have significant adverse impacts on the environment, and therefore can be categorically
excluded from preparation of an EA.
In order to understand the impacts of the ASR Program as a whole, the scope of this PEA includes an
evaluation of the range of potential environmental impacts associated with existing towers and new
towers requiring registration. Because NEPA provides for environmental review only for proposed major
federal actions, however, this PEA considers changes to the FCC’s processes and requirements only for
new or modified towers. The project types examined in this PEA have been categorized into various
groups based on height, location, structure type (self-supported versus guy-wired), and lighting scheme.
Because of the nature of the projects under the ASR Program and in response to the 2008 court decision,
this PEA primarily focuses on potential impacts to migratory birds.
The PEA evaluates the environmental effects of the existing ASR program (No Action Alternative), the
existing ASR program with FAA lighting changes (Alternative 1), and modifications to the ASR program
(Alternative 2 with three options).
The technology of the telecommunications industry is rapidly changing, and new studies and research are
being planned and conducted to examine the environmental impacts of towers, especially related to bird
collisions and impacts to migratory birds. Due to the changing technology and anticipated new studies
1-6

Introduction
examining bird and tower interactions, this PEA encompasses a 10-year planning timeframe. A time-
frame longer than 10 years would not be meaningful, because it would be difficult to project future
conditions, including the number of towers anticipated to be built, reliably. The analysis in this PEA will
be reviewed for adequacy should future major changes to the ASR Program be considered or major
changes to environmental conditions occur.
1.6 PUBLIC INVOLVEMENT
NEPA states that “There shall be an early and open process for determining the scope of issues to be
addressed and for identifying the significant issues related to the proposed action.” The Bureau has
engaged stakeholders and the general public in preparing this PEA. Stakeholders include Federal
agencies, environmental organizations, industry interests, and the public.
1.6.1 Scoping Process
During the PEA planning process, the Bureau provided several opportunities for public and stakeholder
involvement. The Bureau issued a Public Notice in the Federal Register on November 17, 2010 (Vol. 75,
No. 221, pp. 70166-70168), announcing a January 14, 2011, deadline for public scoping comments and
three public scoping meetings to be held in December 2010. These meetings were held as follows:
·
December 6 in the District of Columbia (this meeting was also available as a webcast)
·
December 13 in Tampa, FL
·
December 15 in San Diego, CA
The Bureau also held meetings with various agencies to discuss the development of the PEA.
·
On February 11, 2011, and August 16, 2011, the Bureau met with USFWS representatives to
discuss migratory bird issues.
·
On March 4, 2011, the Bureau met with USFWS representatives to discuss threatened and
endangered species issues.
·
On March 24, 2011, the Bureau met with CEQ representatives to discuss the approach being
taken for the PEA.
On April 1, 2011, the Bureau held a public workshop in the District of Columbia to discuss the project
status, proposed action alternatives, available data, and impact evaluation methods.
1.6.2 Draft PEA
The Bureau considered information obtained during the scoping process in preparing the Draft PEA. The
public was notified of the opportunity to review and comment on the Draft PEA in various ways,
including publication of a notice in the Federal Register and the posting of a notice of the availability of
the Draft PEA on the FCC website. The Bureau also sent e-mail notifications to those individuals who
requested to be notified when the Draft PEA was published and provided direct mailings to individuals
who requested a copy of the document.
The Draft PEA was available for public review between August 26, 2011, and November 2, 2011, via
download from the FCC website in ASCII, Microsoft Word®, and Portable Document Format. Paper
copies of the Draft PEA were available for public review during regular business hours at the FCC
Reference Center, Federal Communications Commission, 445 12th Street, S.W., CY-A257, Washington,
D.C., 20554. Accessible formats (computer diskettes, large print, audio recording, and Braille) were
available via e-mail requests to fcc504@fcc.gov or via telephone requests to the FCC’s Consumer and
Governmental Affairs Bureau at (202) 418-0530 (voice) or (202) 418-0432 (TTY).
1-7

Introduction
1.6.3 Summary
The Bureau solicited public and agency review and comment on the environmental impacts of the ASR
Program PEA through:
·
Public scoping meetings;
·
A public workshop;
·
Meetings and consultations with Federal agencies;
·
Publication of a notice of availability of the Draft PEA in the Federal Register;
·
Publication of the Draft PEA on the FCC website for review;
·
Placement of the Draft PEA in a public repository for review; and,
·
Direct mailing of the Draft PEA to individuals who requested a copy of the document.
Appendix A provides a list of agencies, organizations, and individuals consulted during the NEPA
process.
In addition to involving stakeholders and the general public, the Bureau has coordinated throughout the
process of preparing the PEA with other bureaus and offices within the Commission that have expertise or
regulatory responsibilities relevant to the PEA. Commission staff who reviewed the PEA are identified in
Chapter 10.
1-8

Purpose and Need

SECTION TWO

PURPOSE AND NEED

2.1 PURPOSE
The ASR Program promotes air safety by requiring the registration of antenna structures that may create a
hazard to air navigation due to their height (greater than 200 feet [61 meters] AGL) or proximity to an
airport runway. Through the registration process, environmental impacts from proposed towers are
evaluated. The current ASR Program does not routinely require an applicant to prepare an EA to evaluate
potential impacts to migratory birds.
The purposes of the Proposed Action are to ensure that the ASR program complies with NEPA and
applicable environmental regulations, and to reduce its impacts on migratory birds to an extent consistent
with the Commission’s mandate and authority under the Communications Act. In order to achieve these
purposes, this PEA examines how potential environmental impacts are evaluated as part of the ASR
Program and associated NEPA review and documentation.
2.2 NEED
The U.S. Court of Appeals for the District of Columbia Circuit in American Bird Conservancy, Inc. v.
FCC
(2008) determined that the FCC has not adequately evaluated the potential environmental effects of
its current ASR program on threatened and endangered species and migratory birds. To ensure that the
FCC complies with its obligations under NEPA, there is a need to consider whether the current program
should be revised to require applicants to provide more comprehensive evaluations of potential impacts
on resources, especially migratory birds.
2-1

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Alternatives

SECTION THREE

ALTERNATIVES

The ASR Program is the process under which each antenna structure that requires FAA notification must
be registered with the FCC by its owner. The ASR requirements only apply to those antenna structures
that may create a hazard to air navigation due to height (generally, structures more than 200 feet [61
meters] tall) or proximity to an airport runway. Under the current ASR program, tower registration
applications are categorically excluded from preparation of an EA unless they fall within one of the
categories listed in the FCC NEPA regulations found at 47 CFR § 1.1307(a) and (b), which are presented
below.
The Proposed Action is to modify the ASR Program and associated NEPA compliance procedures, and in
so doing to reduce the program’s impacts on migratory birds to the extent consistent with achieving the
program’s purposes and with the Commission’s authority under the Communications Act. This PEA
reviews the existing ASR Program and NEPA compliance procedures to evaluate their effects on
migratory birds and other environmental resources, in compliance with the 2008 court decision.
On December 6, 2011, the Commission adopted procedures (FCC 2011b) that require applicants for new
tower registration to provide a public notice and 30-day opportunity for comment on the environmental
effects of the proposed construction. The procedures allow agencies and the public a meaningful
opportunity to raise site-specific concerns. The adopted procedures also, as an interim measure, require
applicants to prepare an EA for proposed towers that are more than 450 feet (137 meters) tall to address
potential impacts on migratory birds. Under these procedures, the applicant is not permitted to certify that
the project is categorically excluded until after the FCC has confirmed that it has identified no reason to
require an EA in light of any comments received. For projects requiring an EA, a single 30-day
opportunity for comment may be provided after the applicant prepares the EA. After the close of the
comment period, the FCC will either issue a FONSI or prepare an EIS. The No Action Alternative,
Alternative 1 and Alternative 2 each include the new public notice and comment procedures. Alternative
2 Option C considers the effects of the interim EA requirement for towers more than 450 feet (137
meters) in height becoming permanent.
It should be noted that lighting on new towers must conform to the requirements of the current FAA
Advisory Circular 70/7460-1K Obstruction Marking and Lighting (USDOT/FAA 2007). The FCC cannot
require lighting schemes that are not in compliance with this circular. Currently the FAA does not allow
lighting configurations that use red flashing lights without also requiring the presence of red steady-
burning lights. Following its anticipated publication of the results of a conspicuity study, the FAA may
revise its circular to allow lighting schemes that use red flashing lights without red steady-burning lights.
Therefore, Alternative 1 considers what the effects of the No Action Alternative would be if the FAA
revises its lighting styles. In addition, Chapter 5, Chapter 6, and Chapter 7 describe the effects that each
of the options under Alternative 2 would have on migratory birds both with and without revisions to the
FAA-permitted lighting schemes.
3.1 NO ACTION ALTERNATIVE
The No Action Alternative is defined as continuation of the existing ASR Program and NEPA compliance
procedures, including the public notice and 30-day public comment requirement of the FCC’s recently
adopted procedures, under the existing FAA-permitted lighting configurations (Figure 1).
3-1

Alternatives

Figure 1: NEPA Flow Chart No Action Alternative

Under Section 1.1306, Note 3 of the FCC rules, an antenna farm is "an area in which similar antenna
towers are clustered, whether or not such area has been officially designated as an antenna farm."
The current ASR Program does not routinely require an applicant to prepare an EA to evaluate potential
impacts to migratory birds other than those that are federally listed or proposed as threatened or
endangered. Under the current ASR program, new towers are categorically excluded from requirements to
prepare an EA unless the proposed facility:
·
Would be located in an officially designated wilderness area or wildlife preserve.
·
May affect listed T&E species or designated critical habitat, or is likely to jeopardize the
continued existence of proposed T&E species or result in destruction or adverse modification of
proposed critical habitat.
·
May affect resources listed or eligible for listing in the NRHP or Native American religious and
cultural sites.
·
Would be located in a floodplain.
·
Would involve significant changes in surface features (e.g., wetland fill, deforestation, or water
diversion).
3-2

Alternatives
·
Would be equipped with high intensity white lights and located in a residentially zoned
neighborhood.
·
Would cause human exposure to levels of RF radiation in excess of limits in 47 CFR §§1.1310
and 2.1093.
In these cases, or if the processing Bureau, in response to a petition, on its own motion, or in response to
comments from the public and/or other agencies submitted during the 30-day period for comment under
the FCC’s new notice procedures, determines that an otherwise categorically excluded action has a
potentially significant environmental impact, the applicant must prepare an EA that provides sufficient
analysis for FCC staff to reach a determination that the project would or would not have a significant
environmental impact.
3.2 ALTERNATIVE 1 – EXISTING ASR PROGRAM WITH FAA LIGHTING CHANGES
Alternative 1 is the continuation of the existing ASR Program and NEPA compliance procedures,
including the public notice and 30-day public comment requirement of the FCC’s recently adopted
procedures, along with the potential changes to the FAA’s permitted lighting configurations under which
future towers that use red flashing lights would not also have red steady-burning lights (Figure 2).

Figure 2: NEPA Flow Chart Alternative 1

3-3

Alternatives
The flowchart for Alternative 1 (Figure 2) is the same as for the No Action Alternative (Figure 1) – this is
because FCC rules would not change under Alternative 1. The only change that would occur under
Alternative 1 is that tower owners would have different choices in selecting lighting schemes in
accordance with the revised FAA circular.
The current ASR Program, and thus the program under Alternative 1, does not routinely require an
applicant to prepare an EA to evaluate potential impacts to migratory birds other than those that are
federally listed or proposed as threatened or endangered. Under the current ASR program, new towers are
categorically excluded from requirements to prepare an EA unless the proposed facility:
·
Would be located in an officially designated wilderness area or wildlife preserve.
·
May affect listed T&E species or designated critical habitat, or is likely to jeopardize the
continued existence of proposed T&E species or result in destruction or adverse modification of
proposed critical habitat.
·
May affect resources listed or eligible for listing in the NRHP or Native American religious and
cultural sites.
·
Would be located in a floodplain.
·
Would involve significant changes in surface features (e.g., wetland fill, deforestation, or water
diversion).
·
Would be equipped with high intensity white lights and located in a residentially zoned
neighborhood.
·
Would cause human exposure to levels of RF radiation in excess of limits in 47 CFR §§1.1310
and 2.1093.
In these cases, or if the processing Bureau, in response to a petition, on its own motion, or in response to
comments from the public and/or other agencies submitted during the 30-day period for comment under
the FCC’s new notice procedures, determines that an otherwise categorically excluded action has a
potentially significant environmental impact, the applicant would have to prepare an EA that provides
sufficient analysis for FCC staff to reach a determination that the project would or would not have a
significant environmental impact.
3.3 ALTERNATIVE 2 – MODIFICATIONS TO THE ASR PROGRAM
Under Alternative 2, the FCC would revise its NEPA compliance procedures for the ASR Program to
require more comprehensive assessments of potential environmental impacts from new towers and tower
modifications involving a substantial increase in size, particularly for potential effects to migratory birds.
Alternative 2 would not change the procedures for tower modifications or replacements that do not
involve a substantial increase in size, for certain lighting changes, or for minor ASR actions, including
administrative changes, changes in ownership, dismantling of towers, and minor changes/corrections to
existing towers. It also would not affect activity at registered towers that does not require action in the
ASR system, such as tower repair and replacement of tower parts. Under all options, Alternative 2 would
include the public notice and 30-day public comment requirement in the FCC’s recently adopted
procedures.
There are three options under Alternative 2 for determining the level of NEPA review that would be
required for a project.
3-4

Alternatives
3.3.1 Alternative 2 Option A – Require an EA for All Projects Submitted for Registration

Except for Certain Changes to Existing Towers

Under Alternative 2 Option A, an EA would be required for all new towers outside of an antenna farm
submitted for registration – regardless of location, height, use of guy wires, or lighting scheme – and for
certain replacement towers and changes to existing towers as described below (Figure 3).

Figure 3: NEPA Flow Chart Alternative 2 Option A

Towers in an antenna farm, replacement towers, and modifications of existing towers would require an
EA if they involve a substantial increase in size over the existing tower or towers. A substantial increase
in size is defined as: (1) an increase in height of greater than 10 percent over the existing tower height (or
the tallest tower in the array) or the height of one additional antenna array with separation from the
nearest existing antenna not to exceed 20 feet (6 meters), whichever is greater; (2) a protrusion of more
than 20 feet (6 meters) or more than the width of the tower at the height of the protrusion, whichever is
greater; (3) the installation of more than four equipment cabinets or one equipment shelter; or (4)
excavation more than 30 feet (9 meters) outside the existing tower site. Every EA would need to consider,
in addition to other potential environmental effects, the effects that the project would have on migratory
birds, including individual species of migratory birds to the extent that species-specific information exists,
and on Bald and Golden Eagles.
An EA would also be required for changes to existing towers involving: (1) a change to steady lighting;
(2) a change to high-intensity white lighting in a residentially zoned neighborhood; (3) addition of
lighting; or (4) human exposure to levels of RF radiation in excess of the limits in 47 CFR §§ 1.1310 and
2.1093.
3-5

Alternatives
Under Option A, the only projects that would be categorically excluded from preparation of an EA would
be those that propose any of the following:
·
A change from red steady-burning to flashing lights or removal of lighting on an existing tower
(depending upon potential revisions to the FAA lighting circular).
·
Replacement or modification of an existing tower that involves no substantial increase in size (per
definition).
·
Construction in an antenna farm that does not involve a substantial increase in size over existing
towers.
·
A minor action.
3.3.2 Alternative 2 Option B – Limit which Projects Are Categorically Excluded and

Require an EA for the Rest

Under Alternative 2 Option B, a proposed new tower would require preparation of an EA only under
certain combinations of location and structural and lighting features. Any proposed new registered tower
that requires an EA under the existing rules would require an EA. Also, if a new tower would be
constructed in an important eagle use area, the applicant would have to coordinate with USFWS in
preparing a site-specific EA. If a qualified biologist determines that no Bald or Golden Eagles are or may
be present in the vicinity of a proposed tower, the applicant could presume that the site is not in an
important eagle use area. If Bald or Golden Eagles may be present, the applicant would have to consult
with USFWS to determine whether the site is in an important eagle use area. While it is probable that
eagle use areas generally will be located within 660 feet (201 meters) of a Bald Eagle nest or 0.6 mile (1
kilometer) of a Golden Eagle nest, USFWS may determine that certain towers outside these radii should
require an EA.
Other locational features for which a project may require an EA would include ridgelines, coastal zones,
bird staging areas, colonial nesting sites, or WHSRN sites. If any of those locational features are present,
and a tower would be more than 450 feet (137 meters) tall, would use a red steady-burning lighting
scheme, or would use guy wires, an EA would be required. Towers that are not proposed within any of
these locations or that do not have any of these structural or lighting features would continue to be
categorically excluded, unless they would require an EA under the existing rules or would be located in
an important eagle use area (Figure 4).
3-6

Alternatives

Figure 4: NEPA Flow Chart Alternative 2 Option B

Under Option B, any proposed new tower would be categorically excluded from preparation of an EA
unless it:
·
Would be located in an officially designated wilderness area or wildlife preserve.
·
May affect listed T&E species or designated critical habitat, or is likely to jeopardize the
continued existence of proposed T&E species or result in destruction or adverse modification
of proposed critical habitat.
·
May affect resources listed or eligible for listing in the NRHP or Native American religious
and cultural sites.
·
Would be located in a floodplain.
·
Would involve significant changes in surface features (e.g., wetland fill, deforestation, or
water diversion).
·
Would be equipped with high intensity white lights and located in a residentially zoned
neighborhood.
3-7

Alternatives
·
Would cause human exposure to levels of RF radiation in excess of limits in 47 CFR
§§1.1310 and 2.1093.
·
Would be constructed in an important eagle use area.

OR

would be located in an area considered an important resource for migratory birds, including:
·
ridgelines
·
coastal zones
·
bird staging areas, colonial nesting sites, or WHSRN sites

AND

would:
·
be more than 450 feet (137 meters) tall

OR

·
use a red steady-burning light scheme

OR

·
use guy wires
Towers in an antenna farm, replacement towers, and modifications to existing towers would require an
EA under the same circumstances as new towers if they involve a substantial increase in size, as defined
under Option A. An addition of red steady-burning lights to an existing tower would also require an EA
if the tower is located on a ridgeline or in a coastal zone, bird staging area, colonial nesting site, or
WHSRN site.
An applicant also would have to prepare an EA that provides sufficient analysis for FCC staff to reach a
determination that the project would or would not have a significant environmental impact if the
processing Bureau, in response to a petition, on its own motion, or in response to comments from the
public and/or other agencies submitted during the 30-day period for comment under the FCC’s new notice
procedures, determines that an otherwise categorically excluded action has a potentially significant
environmental impact.
All EAs required under Option B would need to consider, in addition to other potential environmental
effects, the effects that the project would have on migratory birds, including individual species of
migratory birds to the extent that species-specific information exists, and on Bald and Golden Eagles. If
the tower is in a wetland or floodplain and is over 450 feet (137 meters) tall, uses red steady lights, or
uses guy wires, the FCC would expect the applicant to provide either evidence that it is not in a riparian
zone or a detailed analysis of its effects on migratory birds.
3.3.3 Alternative 2 Option C – Make Permanent the Interim Requirement to Prepare an EA
for All Projects More Than 450 feet in Height but Otherwise Do Not Change the
Categorical Exclusion

Under Alternative 2 Option C, in addition to those towers for which an EA is required under the existing
FCC rules, an EA would be required for any proposed new tower, or replacement or modification of an
existing tower that involves a substantial increase in size, that is more than 450 feet (137 meters) AGL,
regardless of location, lighting scheme, or use of guy wires (Figure 5).
3-8

Alternatives

Figure 5: NEPA Flow Chart Alternative 2 Option C

Towers less than or equal to 450 feet (137 meters) AGL would be categorically excluded from
preparation of an EA unless the proposed facility:
·
Would be located in an officially designated wilderness area or wildlife preserve.
·
May affect listed T&E species or designated critical habitat, or is likely to jeopardize the
continued existence of proposed T&E species or result in destruction or adverse modification of
proposed critical habitat.
·
May affect resources listed or eligible for listing in the NRHP or Native American religious and
cultural sites.
·
Would be located in a floodplain.
·
Would involve significant changes in surface features (e.g., wetland fill, deforestation, or water
diversion).
3-9

Alternatives
·
Would be equipped with high intensity white lights and located in a residentially zoned
neighborhood.
·
Would cause human exposure to levels of RF radiation in excess of limits in 47 CFR §§1.1310
and 2.1093.
In these cases, or if the processing Bureau, in response to a petition, on its own motion, or in response to
comments from the public and/or other agencies submitted during the 30-day period for comment under
the FCC’s new notice procedures, determines that an otherwise categorically excluded action has a
potentially significant environmental impact, the applicant would have to prepare an EA that provides
sufficient analysis for FCC staff to reach a determination that the project would or would not have a
significant environmental impact. Every EA would need to consider, in addition to other potential
environmental effects, the effects that the project would have on migratory birds, including individual
species of migratory birds to the extent that species-specific information exists, and on Bald and Golden
Eagles.
3.4 ALTERNATIVES CONSIDERED AND DISMISSED
The CEQ regulations for implementing NEPA require that Federal agencies explore and objectively
evaluate all reasonable alternatives to a proposed action and briefly discuss the rationale for eliminating
any alternatives that are not considered in detail in the NEPA document. Alternatives may be dismissed if
they do not meet the project’s purpose and need or if they are considered not feasible. The following
alternatives were initially considered but then dismissed for the reasons described below.
3.4.1 Prohibit All New Tower Construction
Due to the demand for services that communications towers support, it is not feasible to consider
prohibiting all new tower construction. Therefore, this alternative was dismissed from further
consideration.
3.4.2 Prohibit Towers That Exceed a Certain Height
This alternative would prohibit construction of new towers that exceed a certain height (to be
determined). However, the height of a communications tower is based on several considerations,
including technological requirements for the service to be provided, size of area over which service is to
be provided, topography, distance to other towers, and other factors. Due to these considerations, it is not
feasible to require all towers to be shorter than a certain height. Therefore, this alternative was dismissed
from further consideration.
3.4.3 Prohibit Towers in Certain Locations
This alternative would prohibit construction of new towers in certain locations (to be determined).
However, the location of a communications tower is based on several considerations, such as
technological requirements for the service to be provided, size of area over which service is to be
provided, topography, and distance to other towers. Due to these considerations, it is not feasible to
prohibit all towers in certain locations. Therefore, this alternative was dismissed from further
consideration.
3.4.4 Prohibit Guy Wires on New Towers
This alternative would prohibit construction of new towers that require the use of guy wires. However,
the need for guy wires on a communications tower is based on several considerations, such as the height
of the tower and wind stress. Due to these considerations, it is not feasible to prohibit all towers from
using guy wires. Therefore, this alternative was dismissed from further consideration.
3-10

Affected Environment

SECTION FOUR

AFFECTED ENVIRONMENT

4.1 INTRODUCTION
This chapter provides a description of the primary resources of concern that could potentially be affected
by projects approved under the ASR Program. The existing conditions of these resources serve as a
baseline from which to identify and evaluate potential impacts. Topics discussed include the range of
conditions that may be present at project sites, sources of site-specific resource information, and the
regulatory setting within which the resource is managed or protected.
The ASR Program is national in scale and therefore has the potential to affect resources in all 50 states,
five territories, and the District of Columbia. The projects that would be reviewed and potentially
approved for registration under the ASR Program would be implemented in geographically diverse areas
(both urban and rural), as well as previously disturbed and undisturbed sites. Because of the wide variety
of natural and manmade environments that may be affected by the ASR Program, and the complexity of
resources potentially affected, it is not possible to provide a detailed comprehensive description of locally
affected environments in this PEA. Instead, this chapter characterizes resources in general terms and
identifies those resources that may require additional site-specific analysis (for instance, wetlands). A
discussion of applicable regulations is included to define the relevant considerations applicable to this
PEA.
As described in Chapter 1, development of site-specific EAs for ASR Program projects would still be
needed for individual towers that do not meet the criteria for categorical exclusion.
Communications towers are part of the existing landscape and the following section describes their
general characteristics and distribution.
4.2 EXISTING COMMUNICATIONS TOWERS
Communications towers serve many purposes and support antennas used by various agencies and
industries. They provide support for national defense, homeland security (including border surveillance),
and monitoring maritime vessels in distress. (National defense and other systems operated by Federal
agencies are not licensed by the FCC, and their towers are not required to be registered unless they are
also used for FCC-licensed services.) In addition, antennas on communications towers provide the public
with various communications services such as radio, television, cellular phone, paging, microwave, and
public safety communications (such as police/fire dispatch).
4.2.1 General Characteristics
Communications towers are generally of three construction types: monopole designs (including those
disguised as trees and other stealth towers), lattice structures, and guyed towers. Monopole and lattice
designs are referred to as self-supporting because they do not require guy wires. The three types of
construction are illustrated in Figure 6.
4-1

Affected Environment

Figure 6: Tower Types

A monopole tower is a single tube tower with one foundation; monopole towers typically do not exceed
200 feet (61 meters) in height. Usually, the antennas are mounted on the exterior of monopole towers,
although some stealth designs, such as flagpoles, house the antennas inside the pole. Because they are
limited in height, monopoles are most often used for services that require relatively low antennas, such as
cellular telephones.
Lattice towers afford the greatest flexibility and are often used in heavy loading conditions. A lattice
tower is typically three-sided with a triangular base; however, there are some four-sided lattice towers.
A guyed tower is a straight tower supported by guy wires to the ground, which anchor the tower. Guyed
towers require the greatest amount of land to accommodate the guy wire arrays and anchor points. For
taller heights (roughly 300 feet [91 meters] and greater) it is usually much less expensive to build a guyed
tower than any other kind. Therefore, most radio and television broadcast towers are guyed towers.
All towers that are taller than 200 feet (61 meters) AGL require FAA notification and the FAA usually
prescribes lighting for these towers. Certain shorter towers located near airport runways also require FAA
notification and may require lighting. FCC policy generally prohibits construction of new towers over
2,000 feet (610 meters) in height.
Tower sites also may include other structures such as sheds or outbuildings, as well as ground lighting
and power lines.
4.2.2 Number of Existing Towers
The oldest towers registered in the ASR database date back to 1900. As of February 1, 2012, there were
96,039 towers (i.e., structures coded as “Towers” or “Tower Arrays”) identified in the FCC database as
having a construction date (FCC 2012). (This number more accurately represents the actual number of
existing towers than the subset of towers in “Constructed” status, which was used in the draft PEA.) The
number of new registrations peaked in 1999, 2000, and 2001, and has been trending downward since then.
In particular, reported new registered tower construction has decreased over the last 6 years, from 3,732
new towers in 2006 to 2,013 new towers in 2011. The number for 2011, however, likely undercounts the
number of towers constructed in that year because some applicants have not yet updated their
registrations to indicate that these towers have been constructed.
4-2

Affected Environment
Nearly 67 percent of the towers in the ASR database are less than 301 feet (91 meters) AGL, and 93
percent are less than 451 feet (137 meters) AGL. Less than 1 percent of registered towers are taller than
1,000 feet (305 meters) AGL:
·
0 to 300 feet (0 to 91 meters) AGL
66.7 percent
·
301 to 450 feet (91 to 137 meters) AGL
26.8 percent
·
451 to 1,000 feet (137 to 305 meters) AGL
5.6 percent
·
Greater than 1,000 feet (305 meters) AGL
0.9 percent
4.2.3 Distribution of Existing Towers
There is concentration of towers exceeding 300 feet (91 meters) AGL in the eastern and mid-western
portions of the United States. Towers over 1,000 feet (305 meters) are generally concentrated in the mid-
western and southeastern regions of the United States. As for tower locations outside the 50 states, there
are locations in the territories of Puerto Rico, Virgin Islands, Guam, Northern Mariana Islands, and
American Samoa. (For towers over 300 feet [91 meters], there are locations in Puerto Rico and Guam. For
towers over 1,000 feet [305 meters], there are two locations in Puerto Rico.)
4.2.4 Future Needs/Trends
There are factors suggesting the number of new registered towers constructed each year may continue to
decline, as well as factors suggesting the trend might instead level off or construction might even slightly
increase. One factor suggesting decline is the continued splitting of cells (the area covered by each base
station antenna) to meet needs for capacity. Smaller cells typically require lower antennas, which
frequently can either be collocated on existing structures or placed on shorter towers that do not require
registration and lighting. Another factor that has reduced the need for towers in recent years is
consolidation in the telecommunications industry, which has enabled companies to avoid duplication of
facilities. In addition, the future need for new towers may be reduced due to the development of
distributed antenna system (DAS) technology. Where DAS is deployed, service is provided through a
series of antennas typically mounted at a height of about 30 to 40 feet (9 to 12 meters), which eliminates
the need for many taller towers. A single neutral-host DAS can accommodate multiple carriers. For
economic and other reasons, DAS is not a viable solution for all areas. Where it is deployed, however,
fewer registered towers will be necessary to provide cellular or broadband services.
These factors suggesting a decline in the need for new registered towers may be offset, however, by
initiatives to build out services and bring broadband to rural areas, which may be more efficiently served
by taller towers covering greater areas. The greater availability of funding to build out public safety
systems is another factor that may increase the number of registered towers.
The height distribution of future registered towers may also vary from recent years. In particular, now
that full power stations have completed the transition to digital television, TV broadcasters are unlikely to
need many new towers, and the Bureau therefore expects a significant decline in construction of the
tallest towers (those taller than about 600 feet [183 meters]). On the other hand, increased funding for
public safety systems may lead to more towers in the range of approximately 350 to 450 feet (107 to 137
meters).
The median number of new registered towers constructed each year from 2006 through 2011 is 2,789
towers (3,732 new towers in 2006; 2,932 in 2007; 2,868 in 2008; 2,709 in 2009; 2,680 in 2010; and 2,013
in 2011). Taking into account that the 2011 figure is likely understated, as discussed in Section 4.2.2
above, this PEA uses 2,800 as a conservative estimate of the number of new registered towers anticipated
to be constructed each year over the next 10 years. Although the number of new towers constructed each
year may continue to decrease, it is not possible to predict with any certainty what that decrease will be.
4-3

Affected Environment
The continuing growth of the wireless services industry and the increasing demand for public safety
communications have generated, and will continue to generate, a need for new communications towers
subject to the ASR program. The technology of the telecommunications industry is rapidly changing, and
new studies and research are being planned and conducted to examine the environmental impacts of
towers, especially related to bird collisions and impacts to migratory birds. Due to the changing
technology and anticipated new studies examining bird and tower interactions, this PEA encompasses a
10-year planning timeframe. A time-frame longer than 10 years would not be meaningful, because it
would be difficult to project future conditions, including the number of towers anticipated to be built,
reliably.
4.3 RESOURCES NOT AFFECTED
The No Action Alternative, Alternative 1, and the three options under Alternative 2 are anticipated to
have no impacts or negligible impacts on the resources listed. Negligible impacts are barely perceptible or
measurable and remain localized and confined. A brief discussion of each resource and the rationale for
its dismissal from further analysis is provided below.
4.3.1 Geology
The No Action Alternative, Alternative 1, and all options of Alternative 2 are expected to result in no
impacts or negligible impacts to geology. All alternatives would require some excavation and earthwork;
however, the excavation would not likely be deep enough to affect the geologic character of the site(s).
Therefore, this resource topic is not addressed further in this PEA.
4.3.2 Soils
Under the No Action Alternative, Alternative 1, and all options of Alternative 2, surficial ground
disturbance would occur within the footprint of the communications tower and any guy wire anchor
points, if the tower is to be supported by guy wires. Because of the small amount of excavation required
to construct a tower, adverse impacts to soil would be short-term and negligible under all alternatives.
Therefore, this resource topic is not addressed further in this PEA.
4.3.3 Farmlands
Prime and unique farmlands and farmlands of state and local importance are protected under the
Farmland Protection Policy Act of 1981 (7 U.S.C. § 4201 et seq.). Prime farmland is characterized as land
with the best physical and chemical characteristics for the production of food, feed, forage, fiber, and
oilseed crops. Prime farmland is either used for food or fiber crops or is available for those crops; it is not
urban, built-up land, or water areas. Unique farmland is defined as land that is used for the production of
certain high-value crops, such as citrus, tree nuts, olives, and fruits. Federal agencies must examine the
potentially adverse effects to prime or unique farmlands or farmlands of state or local importance before
approving any action that would irreversibly convert farmland to non-agricultural uses.
Farmlands are often sought as sites for communications towers to meet the need for telecommunications
services in rural areas. Under the No Action Alternative, Alternative 1, and all options of Alternative 2,
construction of new towers in areas containing protected farmland soils would convert only small
amounts of farmlands within the tower footprint and guy wire anchor points (if needed) to non-
agricultural (tower) use. In most cases, continued agricultural use of the farmland surrounding the tower
would continue. Therefore, impacts to farmlands would be negligible and this resource topic is not
addressed further in this PEA.
4-4

Affected Environment
4.3.4 Groundwater
The No Action Alternative, Alternative 1, and all options of Alternative 2 are anticipated to have no
impacts or negligible impacts to groundwater. Excavation and earthwork for new towers would be
relatively minor and localized and applicants would be required to adhere to Federal, state, and local
regulations that protect groundwater resources. Therefore, this resource topic is not addressed further in
this PEA.
4.3.5 Coastal Zones/Coastal Barriers
The coastal zone consists of coastal waters and the adjacent shore lands, strongly influenced by each other
and in proximity to the shorelines of the several coastal states. The coastal zone includes islands,
transitional and intertidal areas, salt marshes, wetlands, and beaches. The zone extends, in Great Lakes
waters, to the international boundary between the United States and Canada and, in other areas, seaward
to the outer limit of State title and ownership. The zone extends inland from the shorelines only to the
extent necessary to control shore lands, the uses of which have a direct and significant impact on coastal
waters, and to control those geographical areas which are likely to be affected by or vulnerable to sea
level rise. Excluded from the coastal zone are lands the use of which is by law subject solely to the
discretion of or which is held in trust by the Federal government.
The Coastal Zone Management Act of 1972 (16 U.S.C. § 1451 et seq.) is administered by the Department
of Commerce’s Office of Ocean and Coastal Resource Management within the National Oceanic and
Atmospheric Administration. It applies to all coastal states and to all states that border the Great Lakes.
The Federal Consistency provision, contained in Section 307 of the Act, allows affected states to review
Federal activities to ensure that they are consistent with the state’s coastal zone management program.
The Coastal Barrier Resources Act of 1982 (16 U.S.C. § 3501 et seq.) protects coastal areas. These areas
serve as barriers against wind and tidal forces caused by coastal storms and also provide habitat for
aquatic species. One of the goals of the Act is to protect the natural resources associated with coastal
barriers and this goal is applicable to the construction of communications towers. Currently, the Coastal
Barrier Resources System includes 585 system units along the Atlantic Ocean, Gulf of Mexico, Florida
Keys, Great Lakes, and Puerto Rico.
The No Action Alternative, Alternative 1, and all options of Alternative 2 are expected to result in
negligible impacts to the coastal zone or coastal barrier resources because towers constructed in these
areas would require only small amounts of disturbance to soils and vegetation within the footprint of the
communications tower and any guy wire anchor points needed. However, coastal zones and coastal
barriers contain important habitats for migratory birds and towers located in these areas may affect
migratory birds; therefore, these areas are discussed in Section 4.6.3 and Section 5.4.3.3.
4.3.6 Designated Wilderness Areas
The Wilderness Act of 1964 established the National Wilderness Preservation System and a process for
Federal land management agencies to recommend wilderness areas to Congress. Hundreds of wilderness
zones within already protected federally administered property, consisting of over 9 million acres (3.6
million hectares), comprised the original National Wilderness Preservation System. As of August 2008, a
total of 704 separate wilderness areas, encompassing 108 million acres (44 million hectares), had been set
aside. With the passage of the Omnibus Public Lands Act in March 2009, the number increased to 756
wilderness areas. This is approximately 5 percent of the entire U.S. land area, though only about 2.5
percent of the 48 contiguous states. Wilderness areas exist in every state except Connecticut, Delaware,
Iowa, Kansas, Maryland, and Rhode Island.
Wilderness, as defined by the Wilderness Act, is untrammeled (free from man's control), undeveloped,
and natural, and offers outstanding opportunities for solitude and primitive recreation. People value
4-5

Affected Environment
wilderness for its wildlife; scenery; clean air and water; and opportunities for solitude, personal growth
experiences, and a sense of connection with nature and values beyond themselves.
Communications towers are rarely proposed within wilderness areas because of the remoteness of many
of these areas and the difficulties of obtaining managing agency approval. Furthermore, in the event a
tower is proposed for construction in a wilderness area, the FCC rules require preparation of an EA.
Therefore, the No Action Alternative, Alternative 1, and all options of Alternative 2 are expected to result
in negligible impacts to designated wilderness areas and these areas are not addressed further in this PEA.
4.3.7 Air Quality
The Clean Air Act, as amended, requires the U.S. Environmental Protection Agency (EPA) to set two
types of National Ambient Air Quality Standards for pollutants considered harmful to public health and
the environment. Primary standards set limits to protect public health, including the health of “sensitive”
populations, such as asthmatics, children, and the elderly. Secondary standards set limits to protect public
welfare, including protection against decreased visibility and damage to animals, crops, vegetation, or
buildings. Emissions from backup generators at project sites which contain fuel-burning internal
combustion engines could temporarily increase the localized levels of some pollutants. However, the No
Action Alternative, Alternative 1, and all options of Alternative 2 would not result in any noticeable
short-term or long-term impacts to air quality. The No Action Alternative, Alternative 1, and all options
of Alternative 2 are expected to have negligible impacts on air quality so this resource area is not
addressed further in this PEA.
4.3.8 Noise
The sound environment of the project site(s) would vary, but would generally consist of natural ambient
and human-created sounds (occasional traffic, operation of machinery, etc.). The No Action Alternative,
Alternative 1, and all options of Alternative 2 would result in no long-term differences in noise
frequencies, magnitudes, or durations at the project site(s). Furthermore, because tower construction is a
private activity that is subject to state and local regulations, such as requirements to perform work during
day-time business hours, the Bureau expects that any short-term impacts to adjacent land uses and
populations would be mitigated. Construction workers also are required to comply with Occupational
Safety and Health Administration noise regulations. The No Action Alternative, Alternative 1, and all
options of Alternative 2 are expected to have negligible impacts on noise and this resource area is not
addressed further in this PEA.
4.3.9 Land Use
Land use is the way in which, and the purposes for which, people use the land and its resources. Land use
planning varies depending on land ownership and jurisdictional boundaries. Land use is generally guided
by local comprehensive plans that specify the allowable types and locations of present and future land
use. Land use classifications in the areas considered for ASR Program projects would vary widely
depending on location and would include residential, commercial, industrial, and recreational land uses.
New towers would continue to be subject to review by local jurisdictions and the No Action Alternative,
Alternative 1, and all options of Alternative 2 would not affect those reviews.
4.4 WATER RESOURCES
Water resources refer to the occurrence, availability and physical, chemical, and biological characteristics
of surface water including hydrologic properties and water quality for aquatic plant and animal
communities and public water supplies. Water resources include aquifers, springs, streams, river, lakes,
reservoirs, estuaries, wetlands, and near shore and offshore marine waters. Water use classifications
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Affected Environment
generally include public water supply, recreation, propagation of fish and other aquatic life, agricultural
use, and industrial use.
Water resources are inherently site-specific resources, and this document can only characterize them in
general terms. Site-specific conditions may be discussed in project-specific NEPA documentation, where
required for a project.
Water resources (water quality and quantity) are protected and regulated by many Federal statutes and
EOs, as well as State and local regulations and directives. Surface waters are protected from pollution
originating from point sources such as sewage treatment plant discharges and industrial discharges, and
from non-point sources such as runoff from urban paved areas, mines, and livestock operations. Relevant
Federal statutes and EOs are described below.
4.4.1 Surface Water
Surface waters include springs, streams, rivers, lakes, reservoirs, estuaries, and near shore and offshore
marine waters. Surface waters are naturally replenished by precipitation and lost through natural
processes such as discharge to oceans, evaporation, and subsurface seepage. The total quantity of water
and proportion of water lost in any surface water system are dependent on precipitation in its watershed,
storage capacity, soil permeability, runoff characteristics of land in the watershed, timing of the
precipitation, and evaporation rates.
Human activities can have an impact on the total quantity of water in the system. Impervious surfaces
(e.g., paved roads, parking lots, and buildings) and channelization of streams increase runoff quantities
and velocities. Impacts on water quality come from human activities that cause sediments and pollutants
to enter waterways.
Water quality has two parameters. Chemical water quality describes the general chemical character of
surface water and includes all of the inorganic and organic chemicals found in natural waters for which
humans, other animals, and vegetation have moderate to high tolerance. Changes in chemical quality can
make water unfit for drinking water purposes while still fit for other purposes. Often, changes in chemical
quality are gradual and can go unnoticed until tastes or odors develop. Toxics are heavy metals,
carcinogens, and other inorganic and organic chemicals that, even in low concentrations, might be
harmful to human or animal life; therefore, it is important to prevent contamination of water supplies by
avoiding the potential addition of these harmful materials. Chemical or physical changes and the presence
of toxins in the water might also affect the quality of the surface water for recreational purposes.
Physical water quality describes the attributes of odor, taste, and color of surface water that reflect its
desirability for use. Changes in these attributes can make water undesirable for human consumption.
The EPA regulates primary drinking water supplies under the Safe Drinking Water Act of 1974 (42
U.S.C. § 300f et seq.). This Act was established to ensure safe drinking water for the public and to
prescribe requirements for states to implement the public water supply supervision program and
underground injection control program under the authority of the Act.
Section 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. § 401 et seq.) requires authorization from
the U.S. Army Corps of Engineers (USACE) for construction activities in or near any navigable water of
the United States. The Wild and Scenic Rivers Act of 1968 (16 U.S.C. § 1271 et seq.) preserves selected
rivers in a free-flowing condition and protects their local environments.
4.4.2 Wetlands and Waters of the United States
The Federal Water Pollution Control Act of 1972, better known as the Clean Water Act (CWA) (33
U.S.C. § 1251 et seq., as amended), is the primary Federal law regulating water pollution. The CWA
regulates water quality of all discharges into waters of the United States (WOUS). The term WOUS
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Affected Environment
applies only to surface waters – including rivers, lakes, estuaries, coastal waters, and wetlands – used for
commerce, recreation, industry, sources of fishing, and other purposes. The term “wetlands” means
"those areas that are inundated or saturated by surface or groundwater at a frequency and duration
sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically
adapted for life in saturated soil conditions."
According to the USACE definition of wetlands contained in 33 CFR 328, three conditions must be
present for an area to be classified as jurisdictional wetlands: the area must contain hydric soils; it must
support hydrophytic vegetation; and it must have an appropriate hydrologic regime. Typical wetland areas
include marshes, swamps, and bogs, and, in general, are transitional zones between terrestrial and aquatic
ecosystems. Wetlands are of particular importance to waterfowl and provide habitat for numerous other
wildlife. Wetlands occur throughout the United States and are delineated based on regional or local
criteria determined by the USACE. Wetlands vary extensively because of regional and local differences
in soils, topography, climate, hydrology, water chemistry, vegetation, and other factors, including human
disturbance.
The CWA also establishes state water quality certification requirements under Section 401; dredged or fill
material permit requirements under Section 404; and the National Pollutant Discharge Elimination
System (NPDES) under Section 402. The NPDES Permit Program regulates wastewater discharges from
point sources. Congress has delegated to many states the responsibility to protect and manage water
quality within state boundaries by establishing water quality standards and identifying waters not meeting
these standards, including managing the NPDES system. Facility construction or modifications may
require one or more of the following permits:
·

NPDES General Permit.

This permit may be required for a constructed or relocated facility if
the facility discharges any waters other than to the sanitary sewer.
·

NPDES Stormwater Construction Permit.

This permit is required for any construction activity
that will affect 1 acre or more, unless local restrictions impose a smaller acreage threshold.
Specifically excluded is construction activity that includes “routine maintenance to maintain
original line and grade, hydraulic capacity, or original purpose of the facility.”
Section 404 of the CWA provides for the protection of the nation’s waters and wetlands by establishing a
program regulating the discharge of dredge and fill material within WOUS, including wetlands, and
requiring a permit for such activities. The USACE, EPA, and USFWS jointly administer the wetlands
program. The USACE administers the day-to-day program, including authorizing permits to place dredge
and fill material in WOUS and making jurisdictional determinations of WOUS, including wetlands.
USACE permits are required for all activities resulting in the discharge of dredged or fill material to
WOUS, including wetlands. The USACE has delegated Section 404 permitting authority to some states.
Section 401 of the CWA provides authority for states to require that a water quality certification be
obtained before issuance of a Section 404 permit. Additional protection to surface water and aquatic
biological resources from impacts associated with stormwater runoff is provided by Section 402, which
requires a NPDES permit for various land development activities.
EO 11990 (Protection of Wetlands) requires Federal agencies to minimize the destruction, loss, or
degradation of wetland habitat and to preserve and enhance the natural and beneficial values of wetland
habitat. Wetlands are defined by their hydrologic regime, vegetation characteristics, and soil types.
Although the FCC as an independent agency is not subject to EO 11990, the FCC has made a policy
decision to consider the effects on wetlands as part of its evaluation of the effects on the human
environment under NEPA.
Wetland habitats generally include swamps, marshes, bogs, and similar areas such as sloughs, potholes,
wet meadows, river overflows, mud flats, and natural ponds. Wetlands have important ecological
functions and are biologically diverse. They assimilate nutrients in surrounding surface waters, remove
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Affected Environment
suspended solids and pollutants from stormwater, and protect shorelines from wind and wave action and
storm-generated forces.
The USFWS is the principal Federal agency providing information on the extent and status of the
Nation’s wetlands. The USFWS provides stewardship for the wetlands data that comprise the Wetlands
Layer of the National Spatial Data Infrastructure and makes these data available via the National
Wetlands Inventory Wetlands Mapper on the internet (USFWS 2010a).
Wetlands also contain riparian zones that are important habitats for migratory birds, and towers
constructed in these areas may affect migratory birds, as discussed in Section 4.6.3 and Section 5.4.3.3.
4.5 FLOODPLAINS
Floodplains are defined as areas adjoining inland or coastal waters that are prone to flooding. Floodplain
protection is important to natural resources management because it directly affects surface water quality
and the value of aquatic habitats.
Existing conditions for floodplain resources vary tremendously depending on location. Site-specific
conditions may be discussed in project-specific NEPA documentation, where required for a project. The
Federal Emergency Management Agency produces Flood Insurance Rate Maps (FIRMs) depicting the
spatial layout of areas that may be potentially affected by flood events. In addition to showing the
locations of the 100-year and 500-year floodplains, many FIRMs show the base flood elevation.
FIRMs delineate floodplains with other descriptors, the most important of which are the floodway and the
100-year coastal, high hazard floodplain. The floodway is the channel of a river or other watercourse and
adjacent land areas that are required to remain free from development to discharge the base flood without
cumulatively increasing the water-surface elevation. Because the coastal floodplain is subject to storm
surge floodwaters, this region has more stringent statutes for development than the normal 100-year
floodplain.
EO 11988 (Floodplain Management) requires Federal agencies to determine whether a proposed action
would occur within a floodplain and to take action to minimize occupancy and modification of
floodplains. At a minimum, areas designated as floodplains are susceptible to 100-year floods (defined as
a flood having a 1 percent chance of occurring in any given year). EO 11988 requires that Federal
agencies proposing to site a project in the 100-year floodplain consider alternatives to avoid adverse
effects and incompatible development in the floodplain. If no practicable alternatives exist to siting a
project in the floodplain, the project must be designed to minimize potential harm to, or within, the
floodplain. Furthermore, a notice must be publicly circulated explaining the project and the reasons for its
siting in the floodplain. As an independent agency, the FCC is not subject to EO 11988; however, the
FCC has made a policy decision to consider the effects on 100-year floodplains as part of its evaluation of
the effects on the human environment under NEPA.
Floodplains also contain riparian zones that are important habitats for migratory birds, and towers
constructed in these areas could adversely affect migratory birds, as discussed in Section 4.6.3 and
Section 5.4.3.3.
4.6 BIOLOGICAL RESOURCES
Biological resources include plants and animals and their habitats. In general, biological resources include
native and non-native plants that comprise the various habitats, animals present in such habitats, and
natural areas that help support these plant and wildlife populations. These resources include plant
populations and communities, and wildlife populations and their relationship to habitats, including
upland, aquatic, wetland, and riparian ecosystems.
4-9

Affected Environment
The subsections below provide a description of the affected environment for different types of biological
resources, including descriptions of laws and EOs governing each of these resources. In particular,
because the nature of the ASR Program involves structures that extend hundreds of feet into the sky, the
effect of antenna structures on T&E bird species, migratory birds, and Bald and Golden Eagles is a
principal biological concern. These resources are therefore discussed in more detail below.
4.6.1 Vegetation and Wildlife
Vegetation and wildlife are affected by several factors, including topography, water availability, aerial
extent, connectedness, and interferences attributable to human activity. Distribution and abundance of
terrestrial vegetation and wildlife species are heavily influenced by available habitat. Available habitats
vary significantly across the United States and its territories even within short distances.
Vegetation and wildlife resources vary widely depending on location. These resources include native and
non-native plant species (vegetation) and native and non-native or migratory animal species (wildlife) and
their habitats. Common, broadly classified ecosystems include deserts, grasslands, scrub, woodlands and
forests, aquatic zones, wetlands, and riparian areas. Examples of broad, naturally occurring ecosystems
include old growth coniferous forests in the Pacific Northwest, long-leaf pine forests of the lower eastern
seaboard, and undisturbed areas within the southwestern deserts.
Because terrestrial and aquatic vegetation and wildlife vary widely depending on location, they are
discussed in general terms in this PEA. Potential project sites are located across the United States and its
territories, and providing baseline information for all vegetation and wildlife resources that could be
affected by specific project sites is beyond the scope of this PEA. Site-specific vegetation and wildlife
resources would be addressed in project-specific NEPA documentation, where required for a project.
There are no Federal statutory or regulatory requirements that address non-protected vegetation and
wildlife, but state, regional, or local requirements may apply.
Vegetation and wildlife resources include T&E species and critical habitats, which are addressed
separately in Section 4.6.2.
4.6.2 T&E Species/Critical Habitat
Under the Endangered Species Act of 1973, an endangered species is defined as any species in danger of
extinction throughout all or a significant portion of its range; a threatened species is one that is likely to
become endangered within the foreseeable future.
Section 9 of the ESA prohibits the taking of any endangered wildlife species. Regulations apply the
taking prohibition to most threatened wildlife species as well. Endangered plant species are not subject to
the taking prohibition, but are subject to a prohibition against removing and reducing to possession or
maliciously damaging or destroying them on an area under Federal jurisdiction, or collecting or harming
them in knowing violation of state law or regulation or in the course of violation of state criminal trespass
law.
Section 7 of the ESA requires Federal agencies, in consultation with the USFWS or NMFS, to insure that
any action they authorize, fund, or carry out is not likely to jeopardize the continued existence of a listed
species or destroy or adversely modify designated critical habitat.
There are 1,373 federally listed T&E species broadly distributed throughout the United States and its
territories (USFWS 2011c). Critical habitat has been designated by USFWS for 523 of the listed species
(USFWS 2011b). Identifying and discussing each species and its habitat is beyond the scope of this PEA;
therefore, T&E species and their habitats will be addressed in general terms. Site-specific T&E species
and critical habitats would be addressed in project-specific NEPA documentation, where required for a
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Affected Environment
project. The FCC’s existing rules require preparation of an EA when a project may affect T&E species or
designated critical habitat.
Because towers registered under the ASR program may particularly affect migratory birds, this PEA gives
special attention to T&E bird species. The USFWS currently lists 91 T&E bird species and/or
populations that occur in the United States and its territories (Table 2).

Table 2: Number of Bird Species Listed by Lead USFWS Region

Threatened

Endangered

Lead USFWS Region

Totals

Species

Species

1 – Pacific: ID, OR, WA, HI, Pacific Islands
3
41
44
2 – Southwest: AZ, NM, OK, TX
2
8
10
3 – Great Lakes–Big Rivers: IL, IN, IA, MI, MO,
0
3
3
MN, OH, WI
4 – Southeast: AL, AR, FL, GA, KN, LA, MS, NC,
3
15
18
Puerto Rico/Virgin Islands, SC, TN
5 – Northeast: CT, DE, ME, MD, MA, NH, NJ, NY,
1
1
2
PA, RI, VT, VA, WV
7 – Alaska: AK
2
2
4
8 – California and Nevada: CA, NV, Klamath Basin
4
6
10
area of OR

Totals

15
76
91
Source: USFWS 2011b
Notes: Two species (Heinroth’s Shearwater and Kaempfer’s tody-tyrant) are not included because they are not
native to the United States. Two species (Piping Plover and Roseate Tern) are counted more than once
because these birds have distinct population segments, each with its own individual listed status.

Of the 91 bird species listed as threatened or endangered, 23 species have critical habitat designated.
While designation as a critical habitat does not necessarily preclude development activities, activities that
require a federal permit, approval (such as FCC registration), license, or funding and are likely to destroy
or adversely modify the area of critical habitat require consultation with USFWS.
4.6.3 Migratory Birds
A migratory bird is any species that lives, reproduces, or migrates within or across international borders at
some point during its annual life cycle. The Migratory Bird Treaty Act of 1918 (16 U.S.C. § 703 et seq.)
makes it unlawful to take, possess, buy, sell, purchase, or barter any migratory bird, including feathers or
other parts, nests, eggs, or products, without an appropriate permit. It has been extended to include almost
all birds that have the ability to seasonally relocate within various parts of the United States. The MBTA
prohibits the taking of migratory and certain other birds, their eggs, nests, feathers, or young.
According to rulemaking effective March 31, 2010, the MBTA protects 1,007 species in the 50 states and
5 U.S. territories (USFWS 2010c). The USFWS is the lead agency for managing and protecting
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Affected Environment
migratory birds. Courts have rendered differing decisions regarding the scope of the MBTA’s application
to federal agencies, as well as whether a party may be liable under the MBTA for the unintentional,
incidental death of a migratory bird. The FCC has not established the nature and scope of its
responsibilities, if any, under the MBTA. Because migratory birds are part of the human environment
that is considered under NEPA, however, they are being addressed in this PEA.
The 1988 amendment to the Fish and Wildlife Conservation Act (Public Law 100-653, Title VIII), which
is administered by the USFWS, mandates identification of Birds of Conservation Concern (BCC). The
Act requires that USFWS “identify species, subspecies, and populations of all migratory nongame birds
that, without additional conservation actions, are likely to become candidates for listing under the
Endangered Species Act of 1973.” The Birds of Conservation Concern 2008 (USFWS 2008) is the most
recent list of species, all of which are protected by the MBTA. Birds are listed at three geographic scales:
Bird Conservation Regions (BCRs), USFWS Regions, and National. The 2008 list includes species from
the United States and its territories and is used to identify conservation priorities. Nongame birds, game
birds without hunting seasons, subsistence-hunted nongame birds in Alaska, and ESA candidate,
proposed, listed endangered or threatened, and recently delisted species may be included. The number of
species on each list is as follows: 1) BCR – 10 to 53 species; 2) USFWS Region – 27 to 78 species; and 3)
National list – 147 species.
4.6.3.1 Data Limitations and Uncertainty
In reviewing the available data on migratory birds, factors considered included objectivity, integrity,
transparency, and reproducibility. Information presented in this PEA is based primarily on information
provided in peer-reviewed studies. Every attempt was made to obtain the most complete set of available
data, including studies conducted overseas and throughout the United States, as well as the most recently
published data. USFWS was instrumental in providing many references for review. Studies that are in
preparation and were submitted as part of the docket (e.g., Longcore et al. 2011 in preparation) were also
carefully reviewed and used in the development of the PEA.
There is considerable uncertainty associated with both total migratory bird populations and individual
species populations. Longcore et al. (2011 in preparation) used population estimates from Rich et al.
(2004), who acknowledged that the population estimates they used may vary by as much as an order of
magnitude, although the accuracy of the estimates is higher for the species most affected by towers.
Moreover, these population estimates date from 2001 to 2004. As populations vary from year to year and
decade to decade, the age of the data adds another level of variance that is not acknowledged or addressed
in the manuscripts.
There are not adequate data available that quantify the impacts of various sources of mortality on
individual bird species. Studies suggest that fatality rates at communications towers are not similar for all
migratory bird species and that there may be a disproportionate adverse effect on certain species (e.g.,
Graber 1968, Longcore et al. 2011 in preparation). Some researchers suggest that this adverse effect may
be biologically significant for some species such as Bay-breasted Warbler, Swainson’s Warbler, Harris’
Warbler, and Black-throated Warbler (Longcore et al. 2011 in preparation). In a draft report, Longcore et
al. (2011 in preparation) estimate that towers may disproportionately kill certain bird species when
compared to other sources of mortality. For 12 species, they estimate that mortality at towers is greater
than 1 percent of the total population size and may have an impact on population viability. They further
state that one of these species is endangered, and an additional eight are BCC species.
These estimates, however, are subject to considerable uncertainty. The Longcore et al. manuscript (2011
in preparation) cites many tower kill studies that are 40 to 50 years old, as well as more recent studies.
Given the significant variation in species populations over time, the value of conclusions regarding
population effects drawn from studies conducted over widely divergent time periods is questionable. The
small sample sizes for many of the species evaluated similarly casts doubt on the analysis. Furthermore,
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Affected Environment
several of the cited studies describe extreme episodic events of limited geographical scope at individual
towers, which may introduce bias into their findings (e.g., Brewer and Ellis 1958, Mosman 1975, and
Morris et al. 2003). For example, Mosman (1975) stated that the “…tower was checked whenever I felt
there could have been a kill.” Similarly, Morris et al. (2003) stated that “…visits were made only after
nights of overcast conditions, which were more likely to result in mortality than clear nights.” As a result,
the conclusions drawn by many of the existing studies are not based on typical conditions at a majority of
tower sites. There are only a few studies, such as Gehring et al. (2009), which use a scientifically rigorous
study design that compares avian mortality at different towers.
While additional information on species-specific effects would be relevant to the analysis presented in
this PEA, it would be infeasible and unreasonably costly for the FCC to generate such data on each of the
1,007 migratory species, or even on the 147 nationally identified BCC species, due to the number of
towers that would need to be studied to account for the various migratory routes of these species.
4.6.3.2 Migratory Bird Abundance
Populations of migratory birds can be approximated by extrapolating from the results of a number of
large-scale monitoring efforts. These surveys cover a wide range of geography and habitats, but they do
not necessarily cover all of the areas being considered in this PEA. Databases from these surveys can
provide valuable population estimates suitable for the purpose of characterizing, at least in part, the
affected environment. While these databases may not account for all species, during all seasons (e.g.,
migration), and in all areas, they do provide a sense of the magnitude of the bird populations in the United
States. Databases used to describe bird populations in this PEA did not always include Hawaii and U.S.
territories, and these limitations are noted. Because of these factors, the data presented below may
underestimate the populations for the entire United States and its territories, but are reasonable estimates
for developing a context for evaluating migratory bird abundance. Data from four databases which
consider large-scale monitoring efforts were used to develop estimates for breeding and wintering land
birds and waterfowl and are discussed below.
4.6.3.3 Land Birds – Breeding
Estimates of populations of land birds were obtained by querying the Partners in Flight (PIF) Land Bird
Population Estimates Database, Version 2004. This database was derived from the U.S. Geological
Survey’s Breeding Bird Survey relative abundance data from the 1990s. The PIF database has some
limitations; however, it does provide rough approximations for populations of land birds breeding in the
United States (Blancher et al. 2007). In particular, the PIF database does not include all migratory bird
species in the United States. Currently, there are 1,007 species listed as migratory under the MBTA;
however, the PIF database includes only approximately 448 species.
The PIF data indicate that more than 2.6 billion land birds may breed in the United States (Table 3).
However, the PIF data are not available for Hawaii or the U.S. territories. The USFWS estimates that
there are a minimum of 10 billion migratory birds that breed in North America, with fall populations on
the order of 20 billion (USFWS 2002b). Alaska supports the greatest number of birds followed by Texas.
Not surprisingly, states with larger land areas support a greater number of birds than smaller states.
On a worldwide basis, passerine birds (also called perching birds or songbirds) comprise approximately
5,000 of the nearly 9,000 species of birds; or more than half of all bird species. Similarly, of the just over
700 species of breeding birds known to occur in the United States, more than 400 species (over 50
percent) are passerines and are considered migratory. These species include long-distance migrants that
migrate between South and North America, for example, as well as local migrants that migrate within the
boundaries of the United States. Because passerines are more likely to be found on land, the 448 species
of land birds discussed in this section are predominantly passerine species. Therefore, of the estimated
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Affected Environment
2.6 billion land birds (Blancher et al. 2007), most are passerines (but not all, because owls, hawks, and
grouse are also included as land birds).

Table 3: Population Estimates of Land Birds by State

State

Total Number of Birds

Alaska
354,438,940
Texas
187,720,450
California
127,831,060
Montana
96,785,140
North Dakota
87,086,740
Colorado
76,527,990
Minnesota
73,819,710
Kansas
70,212,480
Oregon
67,704,530
Arizona
66,312,486
Missouri
64,704,690
Illinois
61,380,010
Wisconsin
60,942,926
Washington
57,764,540
South Dakota
56,866,729
New Mexico
56,249,770
Iowa
55,542,900
Oklahoma
53,124,340
Nevada
52,550,223
Nebraska
51,396,276
Michigan
50,539,990
Ohio
49,313,544
Pennsylvania
48,868,111
Idaho
48,673,206
North Carolina
47,758,030
Wyoming
46,782,308
Arkansas
46,710,170
Kentucky
46,386,110
New York
45,410,483
Georgia
45,148,550
Florida
41,062,190
Alabama
40,189,320
Louisiana
39,782,380
Indiana
39,251,680
Tennessee
38,494,330
Utah
36,008,890
4-14

Affected Environment

State

Total Number of Birds

Mississippi
35,899,529
Virginia
34,282,800
Maine
26,071,040
South Carolina
25,810,090
West Virginia
23,122,460
Maryland
11,513,860
Vermont
8,702,387
Massachusetts
7,467,622
New Hampshire
7,247,700
New Jersey
6,764,350
Connecticut
4,070,804
Delaware
2,489,969
Rhode Island
665,500

Total

2,683,449,332
Sourhttp://www.rmbo.org/pif_db/laped/about.aspx">ce: http://www.rmbo.org/pif_db/laped/about.aspx
There is a regional, habitat-based component to these data that is not apparent when sorted by state. Bird
Conservation Regions are distinct ecoregions of North America with similar bird communities, habitats,
and resource management issues. Figure 7 depicts the BCRs in North America. Table 4 presents land
bird population estimates in BCRs, in order of highest to lowest numbers.

Figure 7: Bird Conservation Regions of the United States

Source: USFWS 2008
4-15

Affected Environment
The Eastern Tallgrass Prairie area (associated with portions of the states of Ohio, Indiana, Illinois, Iowa,
Missouri, Nebraska, and Kansas) and the Northwestern Interior Forest (associated with a large portion of
Alaska) have the highest population estimates.

Table 4: Bird Conservation Regions Population Estimates

BCR

Land Bird Population

BCR Name

Number

Estimate

22
Eastern Tallgrass Prairie
207,142,114
4
Northwestern Interior Forest
190,922,700
28
Appalachian Mountains
158,396,314
9
Great Basin
157,718,948
27
Southeastern Coastal Plain
155,551,550
11
Prairie Potholes
153,954,330
10
Northern Rockies
122,233,890
24
Central Hardwoods
114,228,180
5
Northern Pacific Rainforest
112,011,170
19
Central Mixed-grass Prairie
105,730,754
16
Southern Rockies/Colorado Plateau
97,729,720
18
Shortgrass Prairie
97,583,387
23
Prairie Hardwood Transition
95,603,494
17
Badlands and Prairies
94,915,476
2
Western Alaska
71,061,500
12
Boreal Hardwood Transition
69,940,640
25
West Gulf Coastal Plain/Ouachitas
68,206,840
29
Piedmont
65,195,362
32
Coastal California
64,355,370
21
Oaks and Prairies
58,950,640
14
Atlantic Northern Forest
50,810,930
33
Sonoran and Mohave Deserts
49,145,890
26
Mississippi Alluvial Valley
41,476,830
13
Lower Great Lakes/St. Lawrence Plain
38,433,390
3
Arctic Plains and Mountains
38,419,800
35
Chihuahuan Desert
37,417,656
34
Sierra Madre Occidental
30,497,170
30
New England/Mid-Atlantic Coast
27,434,650
31
Peninsular Florida
25,107,880
37
Gulf Coastal Prairie
24,806,109
36
Tamaulipan Brushlands
24,280,200
15
Sierra Nevada
16,885,098
20
Edwards Plateau
15,362,350
1
Aleutian/Bering Sea Islands
1,939,000

Total

2,683,449,332
Source: http://www.rmbo.org/pif_db/laped/about.aspx">http://www.rmbo.org/pif_db/laped/about.aspx
4-16

Affected Environment
4.6.3.4 Land Birds – Wintering
The Christmas Bird Count, currently administered by the National Audubon Society, provides a
significant amount of data for wintering birds. The surveys, which were started in 1900, are conducted in
more than 2,100 count circles throughout the United States, Canada, South and Central Americas,
Mexico, and the Caribbean and Pacific Islands including Hawaii. National Audubon Society’s American
Birds Annual Summary reports contain regional summaries and provide count data. Based on a review of
data for the winters of 2000/2001 through 2009/2010, an average of almost 60 million birds (comprising
about 655 species) winters within the United States. This includes waterfowl, which are counted as part
of a separate monitoring effort described in a subsequent section. Table 5 provides the data for each
winter.

Table 5: Recent Christmas Bird Count Data for the United States

Christmas

Number of Species

Total Number of

Bird Count

Winter

Observed in the

Birds Observed in the

Number

United States

United States

110th
2009-2010
654
51,581,105
109th
2008-2009
NA
61,347,290
108th
2007-2008
665
63,531,134
107th
2006-2007
643
65,109,503
106th
2005-2006
652
57,357,023
105th
2004-2005
652
66,219,394
104th
2003-2004
654
59,552,857
103rd
2002-2003
660
69,456,347
102nd
2001-2002
657
47,241,040
101st
2000-2001
NA
51,657,566

Average

655
59,305,326
Source: National Audubon Society American Birds (2001-2010)
(http://birds.audubon.org/american-birds-annual-summary-christmas-bird-count)
4.6.3.5 Waterfowl – Breeding
Through the Waterfowl Breeding Population and Habitat Survey (WBPHS), the population of ducks
(excluding scoter, eiders, long-tailed ducks, mergansers, and wood ducks) breeding in the United States
can be generally estimated. The WBPHS assesses populations annually in important breeding areas in
Alaska, Canada, and the north-central portion of the United States. This survey covers more than 3
million square miles (7.8 million square kilometers) and is the best source for estimating the population of
ducks in the United States. The 2010 Waterfowl Population Status report (USFWS 2010b) indicates that
the total number of breeding ducks is approximately 9.1 million. This is the sum of the long-term
averages between 1955 and 2009 for regions for which data are available; this number may underestimate
the total number since it does not include other regions that support breeding ducks, including Hawaii and
the U.S. territories. It also does not include geese or other waterfowl species that are not ducks (e.g.,
swans and coots).
4-17

Affected Environment
4.6.3.6 Waterfowl – Wintering
The USFWS mid-winter waterfowl survey provides population estimates for species of ducks (dabbling,
diving, and sea ducks), geese, swans, and coots that winter within the United States. These estimates
provide nationwide data for major concentration areas outside of Hawaii and the U.S. territories. Despite
some potential limitations in the data set due to, but not limited to, differences in field methodology,
changes in personnel, differences in survey effort and changes in areas surveyed, this dataset is the best
currently available for assessing population sizes of wintering waterfowl in the United States (with the
exception of Hawaii and U.S. territories). According to the survey, more than 29 million waterfowl
winter in the United States.
4.6.3.7 Migratory Bird Geographic Patterns
The migratory habits of birds are highly variable among and within individual species but can be
classified into several general categories (Kerlinger, 1995). Short distance migrants include those species
that may wander locally, winter near a small portion of the breeding range, or move to different
elevations, for example. Medium distance migrants may move distances of one to several states. Birds
may move only as far as is needed to take advantage of local food and shelter resources. Kerlinger (1995)
considers these two categories as partial migrants and describes them as the most common types of
migration patterns. Most of the North American birds, including shorebirds, some hawks, and passerines
(e.g., thrushes, orioles, warblers, hummingbirds, and tanagers) are in this category. Long distance
migrants, or complete migrants (Kerlinger 1995), include those species that breed in North America and
completely leave their breeding range to spend the winter in more southern latitudes. Some long distance
migrants have been known to migrate great distances; for example, the Red Knot, which breeds in the
Canadian Arctic and winters in Tierra del Fuego in southern South America approximately 9,300 miles
away. Another form of migration is called irruptive migration, where the patterns are not seasonally or
geographically dependent but, instead, are highly dependent upon availability of food resources.
Just as the distance of migration is highly variable, the routes taken can also be specific to species,
subspecies and populations. Four general major flyways (Atlantic, Mississippi, Central and Pacific) have
been recognized (Figure 8). This terminology, however, oversimplifies most avian migratory patterns.
General routes of migration typically conform closely to major topographical features such as large river
systems or mountain chains.
Generally, migration follows a north-south orientation, although there can be an east-west component
such that elliptically shaped round-trip patterns can occur. Some species may migrate along a narrow
band, particularly those species that are habitat-limited, such as shorebirds which may consistently use the
same stopover points each year. For example, the Delaware Bay is renowned for its importance to hungry
north-bound shorebirds that stop there to feed on horseshoe crab eggs. For many species of songbirds,
migration is along a broad front where the width may be species-specific. Other avian species have
converging routes where the path of migration can become constricted to align with land masses. The
peninsula of New Jersey functions this way to funnel many individuals of many species together.
Banding and modern radar studies provide much of the data used in understanding migration patterns,
including location, abundance, and timing.
4-18

Affected Environment

Figure 8: General Depiction of North American Avian Migratory Flyways

Source: http://www.birdnature.com/flyways.html">http://www.birdnature.com/flyways.html
As shown in some of the examples above, specific geographic features can provide valuable bird habitat
and play an important role in bird migration patterns in both the fall and spring. Topographic features can
also assist, obstruct, or altogether preclude migratory movements. These features include coastal zones,
ridgelines, bird staging areas and colonial nesting sites, and riparian zones – all of which can provide
orientation assistance as well as foraging and resting habitat for migrating birds.
Coastal zones include islands, transitional and intertidal areas, salt marshes, wetlands, and beaches.
Coastal barriers protect coastal areas from wind and tidal forces caused by coastal storms. Both provide
habitat for aquatic species, many of which are a food source for migratory birds such as shorebirds.
Ridgelines are topographical features formed along the highest points of mountain ridges such as the
Appalachian Front. For the purposes of this PEA, a ridgeline is defined as being the elongated crest of a
mountain at least 500 feet (152 meters) above the surrounding landscape, including the area within 100
feet (31 meters) downslope of the peak on either side. Ridgelines are commonly used by migrating raptors
because of the thermal updrafts used in soaring that are found there. As summarized in Longcore et al.
(2008), topographical features such as ridgelines may be important habitat features for migrating
neotropical songbirds as well. Studies such as Williams et al. (2001) reported large numbers of migrants
at low flight elevations along ridgelines in New Hampshire. In addition to helping birds orient themselves
during migration, ridgelines may further assist migrating birds by reducing the amount of energy
expended because birds can ride in updrafts coming from these features. However, the general consensus
is that the birds most at risk from collisions with communications towers (migratory songbirds) generally
migrate in broad spatial fronts and do not concentrate along ridgelines as raptors do (Gauthreaux et al.
2003, Faaborg et al. 2010).
4-19

Affected Environment
Geographically relevant staging (stopover) areas provide important foraging opportunities and shelter
where migratory birds can rest and add fat reserves prior to continuing on their migration route. For
example, many undeveloped areas along the Gulf coast are important stopover locations for the high
numbers of north-bound songbirds that land there after crossing the Gulf of Mexico in the spring. They
provide high quality and ecologically important habitat necessary for bird survival during migration,
breeding, and wintering seasons. The locations of these areas are well known by state wildlife agencies
and USFWS.
Colonial nesting sites contain multiple nests of breeding birds and are found throughout the United States.
Colonial nesting sites can be composed of mixed species or a single species, many of which are
migratory, and the number of individuals and nests can vary greatly. Common colonial nesting bird
species belong to two major groups – seabirds (albatrosses, shearwaters, pelicans, gulls, storm-petrels,
etc.) and wading birds (ibis, egrets, herons, spoonbills, night-herons, bitterns and storks) (USFWS 2002a).
Typically, colonial nesting sites are located in inaccessible areas associated with remote terrestrial,
aquatic, and wetland habitats that also support other birds as stopover feeding/resting points during
migration. Use of the colonial nesting site during the year is dependent upon the species’ breeding cycle
for that area. Colonial nesting site locations typically can be identified in coordination with USFWS or
state wildlife agencies.
The seasonal migrations of shorebirds are timed to occur just as their food sources become available at
very specific locations across the hemisphere during very short windows of time. Western Hemisphere
Shorebird Reserve Network (WHSRN) sites were developed as the framework for a site-specific,
hemisphere-scale shorebird conservation strategy by scientists concerned about population declines in
shorebirds. This strategy is aimed at sustaining healthy populations of shorebirds by maintaining the
ecological integrity of key sites that provide the habitat needed for survival. There are three categories of
WHSRN sites –hemispheric, international, and regional. Site boundaries are available from the WHSRN
website (http://www.whsrn.org).
Riparian zones occur throughout the United States as long strips of vegetation adjacent to streams, rivers,
lakes, reservoirs, and other inland aquatic systems that affect or are affected by the presence of water.
This vegetation contributes to unique ecosystems that perform a large variety of ecological functions.
There is no universally recognized or widely accepted definition that adequately describes all riparian
zones (Anderson 1976). Stream and river ecosystems differ regionally and locally in many characteristics,
including width, depth, frequency of flooding, hydrogeomorphic factors, and vegetation. These
differences are most apparent between eastern and western regions of the United States. Riparian zones in
the western United States tend to be much narrower than in the East and contrast highly with surrounding
uplands. Although riparian zones comprise a very small proportion of most landscapes, they frequently
are used by wildlife in much greater proportion to their availability. Riparian zones in the western United
States comprise less than 1 percent of the total land area, yet these areas are used by more species of
breeding birds than any other habitat in North America (Knopf et al. 1988). Riparian zones are an
extremely important component of wetland and floodplain ecosystems, and provide foraging and
sheltering areas for migratory birds.
4.6.3.8 Migratory Bird Flight Altitudes
Most birds generally fly below 500 feet (152 meters; Ehrlich et al. 1988); however, heights on migration
flights vary among groups of birds as a function of whether they are day or night migrants and whether
they migrate over land or water. According to the Cornell Laboratory of Ornithology website on
migration, songbirds largely migrate nocturnally within 2,100 to 2,400 feet (641 to 732 meters) of the
land surface. In Kerlinger’s (1995) book on bird migration, he reports that 75 percent of songbirds
migrate nocturnally within 2,000 feet (610 meters) above the ground, as confirmed in numerous radar
studies. Over water, songbird migration occurs at higher altitudes. Shorebirds can also migrate within
the same zone as songbirds, but generally migrate near 3,000 feet (914 meters). Waterfowl show more
4-20

Affected Environment
variation and are largely found at 100 to 200 feet (31 to 61 meters). Some waterfowl may even move just
above the water. For soaring birds such as hawks and gulls, migration begins as the thermals and updrafts
upon which they rely develop during the morning hours. As the day heats up, soaring activity increases
and so does the elevation of activity. Over the course of a day, soaring birds are typically migrating at
600 feet to 1,500 feet (183 to 457 meters) and higher, with the maximum height approximately 3,500 to
4,000 feet (1,067 to 1,219 meters). Birds gliding in updrafts along ridgelines or over water may occur at
relatively low levels (5 to 20 feet [1.5 to 6 meters]) or as high as 600 feet (183 meters). Figure 9 shows
migratory flight altitudes for various bird groups.
8000-9000
7000-8000
6000-7000
5000-6000
4000-5000
3000-4000
Altitude (feet)
2000-3000
1000-2000
0-1000
Over
Over
Over
Over
Over Water
Over Land
Thermals Ridges
Water
Land
Water
Land
Day
Night
Day
Night
Day or Night
Day or Night
Day
Songbirds
Shorebirds
Waterfowl
Soaring Birds

Figure 9: Migratory Flight Altitudes for Various Bird Groups

Source: adapted from Kerlinger 1995
4.6.3.9 Timing of Migration
According to Lincoln et al. (1998) and Kerlinger (1995), smaller birds or those using powered flight, such
as many songbirds, shorebirds and rails, typically migrate at night. This nocturnal pattern is more typical
for birds than diurnal migration. Flight begins after sunset and activity peaks soon after. Soaring birds
(hawks, pelicans, cranes and swallows), however, migrate during the day because many of them rely on
thermals and updrafts that develop a few hours after sunrise. Migration activities cease as the
thermals/updrafts dissipate in late afternoon. Other daytime migrants include some species of waterfowl,
gulls, nighthawks and swifts. Wading and diving birds will migrate during the day or at night.
In North America there are two general migration seasons, spring and fall, though the timing and duration
of migration is variable. Different species within a group can show differing migration schedules just as
populations within the same species can differ with respect to timing.
Spring patterns show movement northward toward the breeding grounds. Though some bird species may
move relatively early in the year, other species are still migrating in June. Fall migration can be similarly
drawn out. Lincoln et al. (1998) indicate that populations breeding in the southern portion of a species’
range may migrate before a population to the north, simply because breeding is completed sooner. Fall
migration may begin soon after post-breeding dispersal in late summer and continues well into the fall
months.
4.6.3.10 Avian Mortality from Communications Towers
Manville (2001) estimated annual bird mortality from communications towers at 4 to 5 million birds and
indicated that mortality might actually range as high as 40 to 50 million birds. The lower end (4 to 5
million) of Manville’s estimate has been frequently cited in other papers as a reasonable approximation of
4-21

Affected Environment
bird kills at towers (e.g., Gehring et al. 2009, Gehring et al. 2011). Most recently, Longcore et al. (2012
in press) have estimated annual avian mortality at towers in the United States and Canada at 6.8 million
(6.6 million in the United States and 0.2 million in Canada). In assessing impacts, the Bureau
conservatively uses the estimate offered by Longcore et al. (2012 in press) that the annual avian mortality
caused by towers in the United States is 6.6 million birds. The ASR program does not include towers
outside the United States.
Appendix B provides a summary of the existing data sources that report avian mortality at individual
communications towers and that were used in developing this PEA.

Geographic Distribution


Longcore et al. (2012 in press) have proposed that mortality is not equal across geographic regions. The
number and height of towers in an area appear to influence geographic trends in mortality. Mortality was
estimated to be highest (about 1.1 million birds annually) in the southeastern United States (Southeastern
Coastal Plain Bird Conservation Region which includes parts of VA, NC, SC, GA, FL, AL, MS, LA,
TN), where there is a higher proportion of tall towers. This rate is higher than for all of Canada (almost
221,000 birds annually), where towers tend to be fewer and shorter. Since mortality generally occurs
during migration, mortality is not related to local population size of migratory birds. For example, in
Alaska, which is estimated to support more than 354,000,000 breeding birds, the mortality rate from
collision with communications towers is estimated to be about 2,800 birds annually. In Alaska, there are
fewer towers per unit area when compared to other states.

Species-specific Effects


Longcore et al. (2011 in preparation) have proposed that mortality at communications towers is not equal
across all avian taxa. Mortality has been observed for 239 species in the United States and Canada
(Longcore et al. 2011 in preparation). Observed mortality is highest for neotropical migrants, and for
some of these species mortality has been estimated to be more than 1 percent of the species’ population,
which the authors term “biologically significant.” The birds that appear to be most vulnerable to
communications towers comprise approximately 350 species of neotropical migratory birds. In particular,
these species include thrushes, vireos, and warblers, which migrate at night and are therefore susceptible
to collisions with towers, especially on foggy nights or on nights with low cloud ceilings during spring
and fall migrations (Manville 2001). Longcore et al. (2011 in preparation) estimate that 95 percent of
tower mortality consists of passerines (songbirds), and that among passerines, mortality rates are highest
for warblers (52 percent of all mortality; 3+ million individuals annually), vireos (11 percent; nearly 2
million), sparrows (9.5 percent; almost 350,000) and thrushes (6 percent, almost 258,000). The authors
suggest that mortality may be more than 1 percent of the species population for 12 species (range 1-8
percent), eight of which are warblers. One of the 12 is endangered, and eight are Birds of Conservation
Concern.
As noted above in Section 4.6.3.1, the Longcore et al. (2011 in preparation) results were based on a meta-
analysis of existing studies. While the analysis encompasses a thorough review of the literature, it relies
on studies that were not designed to identify species-specific impacts; it relies heavily on studies that
describe extreme episodic events; it draws major conclusions from very small sample sizes; and it mixes
data from widely divergent time periods during which species populations may vary by as much as an
order of magnitude (Rich et al. 2004). Therefore, the Bureau does not consider its conclusions to be
reliable. While the Bureau acknowledges that information on species-specific effects would be relevant to
the analysis presented in this PEA, it would be infeasible and unreasonably costly for the FCC to generate
data on species-specific effects from communications towers nationwide on each of the 1,007 migratory
species, or even on the 147 nationally identified BCC species, due to the number of towers that would
need to be studied to account for the various migratory routes of these species. CEQ does not require that
an agency obtain information that is essentially unattainable due to exorbitant costs or the lack of the
means to obtain the information (40 CFR 1502.22[a]). Moreover, depending on the alternative adopted,
4-22

Affected Environment
the Commission’s NEPA procedures will effectively provide for consideration of impacts on individual
species in circumstances where a site-specific EA is required. Under any alternative, the processing
Bureau may require an EA to address site-specific impacts on a species in response to comments or on its
own motion under Section 1.1307(c) or (d) of the Commission’s rules.

Declining Mortality Hypothesis


Over the last five decades of monitoring bird populations, the number of bird mortalities at towers is
reported to be decreasing while the number of towers is increasing (Morris et al. 2003). Morris et al.
compared mortality data from 1970 to 1999 for four separate towers (three in New York and one in
Ohio), which were all approximately 1,000 feet (305 meters) in height. The comparison reported a
significant decrease in the number of birds salvaged at all four towers within the 30-year period,
suggesting a corresponding reduction in the number of birds that collided with the towers during the same
period. According to Morris et al. (2003), other long-term studies consistently show a similar decline in
total bird mortality (with other factors remaining equal, e.g., tower height). These researchers suggested
that this reduction in bird mortality might be due to the following:
1. An overall decrease in migratory bird populations;
2. Potential changes in patterns of wind direction, cloud cover, and visibility;
3. An increase in predator and scavenger removal of bird carcasses at tower sites;
4. A change in migration patterns; and,
5. An increase in background light pollution (with a resulting decrease in migrant attraction to tower
lighting).
However, when comparing the similar and parallel reduction in number of bird mortalities at the four
tower sites, Morris et al. (2003) suggest that the factors affecting the observed decline in migrant
mortality at communications towers are more likely large-scale factors, such as weather patterns and
population size, rather than more site-specific factors, such as an increase in scavengers.
Nehring and Bivens (1999) reviewed a 38-year mortality study at a 1,364-foot (416-meter) tower in
Tennessee and report a similar decline in mortality rate and species diversity over time. Even after
removing two mass kills (in 1968 and 1970), the long-term trend showed a significant reduction in the
number of birds killed. Nehring and Bivens (1999) offer these three potential causes for the observed
decline:
1. A change in migration routes to avoid the urban expansion of Nashville, Tennessee;
2. An increase in background light pollution, which reduces the attraction to the tower lights (same
as #5 above);
3. An increase in scavenging rates, resulting in a decrease in birds recovered, which is not indicative
of a true decline in mortality (same as #3 above).
While there is some compelling data suggesting an overall reduction in bird mortality at towers over the
last five decades, this trend is best viewed as being hypothetical because it has been observed at only a
few towers. Therefore, additional research on the declining mortality hypothesis is needed.
4.6.3.11 Other Sources of Avian Mortality
In addition to communications towers, there are other anthropogenic causes of mortality in birds,
including collisions with buildings, windows, motor vehicles, and wind turbines, as well as predation by
cats. Erickson et al. (2005) summarized these sources of bird mortality and estimated that 500 million to
possibly over 1 billion birds are killed annually. However, subsequent studies of collisions with building
glass (Klem et al. 2009) and predation by cats (Dauphiné and Cooper 2009) indicate that these estimates
4-23

Affected Environment
are low and that annual mortality from these two sources likely exceeds 2 billion birds. These studies
reference data from other sources that report the great majority of deaths are to migratory birds. For
example, there is evidence that the species of birds most commonly killed by buildings, one of the major
sources of anthropogenic avian deaths, are migratory species (Klem et al. 2009).
Avian collisions with buildings and power lines and cat predation appear to cause the bulk (> 80 percent)
of all avian mortality attributable to human activity and cats. Klem et al. (2009) report that “…except for
habitat destruction, collisions with clear and reflective building sheet glass cause the deaths of more birds
than any other human-related avian mortality factor.” They conservatively estimate that 1 billion birds
are killed annually from collisions with building glass in the United States alone. The report further states
that of the top ten species collected during two studies (one in autumn and one in spring) of collisions
with buildings, ten and nine species, respectively, were migratory. Dauphiné and Cooper (2009) report
that free-ranging domestic cats may kill “at least one billion birds” every year in the United States,
although they do not provide an estimate of how many of these birds may be migratory. However, the
studies they reference (e.g., Balogh and Marra 2008; Hawkins et al. 2004) describe cat predation as the
primary source of mortality to species (e.g., Gray Catbird and California Thrasher) that are listed as
migratory. This and other studies have shown that domestic cats pose threats to many bird populations
through their predation of adult, nestling, and juvenile birds. Predation risk from cats may also cause
stress responses in birds that may contribute to bird population declines (Dauphiné and Cooper 2009).
Table 6 summarizes the mortality estimates from several sources.

Table 6: Sources and Estimates of Annual Avian Mortality in the United States (in millions)

Dauphiné

Klem

Erickson

NWCC

American

Mortality

and

Sibley

et al.
et al.

Committee

Bird

Source

Cooper

Guides

(2009)
(2005)
(2001)

Conservancy

(2009)
Buildings/
1,000
-----
550
98 – 980
97 – 976
-----
Windows
Power lines
-----
-----
130
0.01 – 174
174
10 – 154
Cats
-----
1,000
100
NA
500
-----
Vehicles
60
-----
80
60 – 80
60
10.7 – 380
Pesticides
-----
-----
67
-----
72
-----
Hunting
120
-----
-----
-----
15
-----
Communications
-----
-----
4.5
4 – 50
5 – 50
4 – 50
towers
Wind turbines
0.4
-----
0.0285
0.01 – 0.04
0.033
0.01 – 0.04
Airplanes
-----
-----
0.025
-----
-----
-----
Sources: ABC Source (http://www.abcbirds.org/abcprograms/policy/collisions/index.html">www.abcbirds.org/abcprograms/policy/collisions/index.html)
Sibley Guides Source (http://www.sibleyguides.com/">www.sibleyguides.com)
As discussed previously, the majority of birds killed by collisions with communications towers are
migratory neotropical songbirds. The other sources represented in Table 6 also result in mortality to
neotropical migratory songbirds, although there is not clear evidence of the percentages of songbirds that
are included in the totals.
Human-caused avian mortality occurs in the context of a high level of natural mortality to bird
populations during migration. Although there is very little available information on species-specific
4-24

Affected Environment
impacts, it is fairly well-documented that a large percentage of migratory birds die during migration.
Sources of mortality include lack of sufficient stopover habitat, predation, and exhaustion. For example,
Sillett and Holmes (2002) found that 85 percent of the population of Black-throated Blue Warblers dies
annually during migration. Given that many of the birds killed by human activity and cats may have died
during migration in any event, the extent to which migratory bird deaths from these sources are
incremental to natural mortality is not well understood.
4.6.4 Bald and Golden Eagles
Bald Eagles historically occurred throughout the contiguous United States and Alaska. After severely
declining in the lower 48 states between the 1870s and the 1970s, Bald Eagles have rebounded and re-
established breeding territories in each of the lower 48 states. The largest North American breeding
populations are in Alaska and Canada, but there are also significant Bald Eagle populations in Florida, the
Pacific Northwest, the Greater Yellowstone area, the Great Lakes states, and the Chesapeake Bay region.
Bald Eagle distribution varies seasonally. Bald Eagles that nest in southern latitudes frequently move
northward in late spring and early summer, often summering as far north as Canada. Most eagles that
breed at northern latitudes migrate southward during winter, or to coastal areas where waters remain
unfrozen. Migrants frequently concentrate in large numbers at sites where food is abundant, often roosting
together communally. In some cases, concentration areas are used year-round: in summer by southern
eagles and in winter by northern eagles (USFWS 2007).
Bald Eagles generally nest near coastlines, rivers, large lakes, or streams that support an adequate food
supply. They often nest in mature or old-growth trees, snags (dead trees), cliffs, rock promontories, and
with increasing frequency on manmade structures such as power poles and communications towers
(USFWS 2007).
Golden Eagle populations are believed to be declining throughout their range in the contiguous United
States (Kochert and Steenhof 2002, Kochert et al. 2002, Good et al. 2007, Farmer et al. 2008, Smith et al.
2008). Golden Eagles will migrate from the Canadian provinces and northeastern states to areas that are
milder in the winter or have less snow cover. Wintering Golden Eagles have been identified in all states in
the continental United States. Golden Eagles are not known to roost communally as is common with
wintering Bald Eagles in some areas of the U.S, but will gather together if local food sources are abundant
(Palmer 1988).
Golden Eagles nest on cliffs and in the upper portions of deciduous and coniferous trees, or on artificial
structures such as windmills, electric transmission towers, and artificial nesting platforms (Phillips and
Beske 1990, Kochert et al. 2002). Golden Eagles currently breed in and near much of the available open
habitat in North America west of the 100th Meridian, as well as in the northern Appalachian Mountains of
the eastern United States (Palmer 1988, Kochert et al. 2002), although they are not common in the eastern
half of the United States. Golden Eagles avoid nesting near urban areas and do not generally nest in
densely forested habitat. Individuals will occasionally nest near semi-urban areas where housing density
is low and in farmland habitat; however, Golden Eagles have been noted to be sensitive to some forms of
human presence (Palmer 1988).
The Bald and Golden Eagle Protection Act (BGEPA) of 1940 (16 U.S.C. § 668 et seq.) ensures the
protection of Bald and Golden Eagles. The BGEPA prohibits anyone without a permit from “taking” bald
and golden eagles, including their parts, nests (active and inactive) or eggs. “Take” includes pursue,
shoot, shoot at, poison, wound, kill, capture, trap, collect, molest or disturb.
Although the BGEPA does not specify the distances required to protect active Bald and Golden Eagle
nests from human-induced impacts, concern over disturbance of Bald and Golden Eagle nests has resulted
in the recommendation of spatial or temporal buffers (restriction of activity within an area or period of
time) to reduce impacts. Temporal buffers may supplement or be used in place of spatial buffers.
4-25

Affected Environment
Temporal buffers typically extend from the time of arrival of the adult birds in the nesting area through
the first few weeks of nesting development.
Scientific support for buffer distances to protect breeding eagles from human activities is limited
(Whittington et al. 2010). The USFWS has developed guidelines for Bald Eagles, which recommend no
construction activity within 660 feet (0.2 kilometer) of an active Bald Eagle nest during nesting season if
the construction activity would be visible from the nest (USFWS 2007). No USFWS guidelines exist for
Golden Eagles and there is little published literature with information on appropriate buffer distances for
their nests. Suter and Joness (1981) recommended no construction activity occur within 0.6 mile (1
kilometer) of an active Golden Eagle nest during the nesting season to avoid nest abandonment.
4.7 CULTURAL RESOURCES
The primary Federal regulation requiring consideration of historic properties is Section 106 of the
National Historic Preservation Act of 1966 (16 U.S.C § 470 et seq.). NEPA review may also encompass
the consideration of effects on cultural resources that do not qualify as historic properties under the
NHPA.
Under the NHPA, historic properties are defined as districts, sites, buildings, structures, or objects listed
in or eligible for listing in the National Register of Historic Places, a list that is maintained by the
Department of the Interior, National Park Service. Typically, historic properties can be placed into the
following categories:
·

Archaeological resources.

This includes prehistoric or historic sites where human activity has
left physical evidence of that activity. These may be associated with buildings, structures, and
landscapes that remain aboveground.
·

Architectural and landscape resources.

This includes buildings, structures, districts, or objects
that have historic or architectural significance. Battlefields would be included in this category.
·

Traditional Cultural Places and Tribal Religious or Cultural resources.

These include
resources that are used by a group for traditional cultural purposes or that have religious or
cultural significance to a Native American Tribe (including Alaska Native Villages) or Native
Hawaiian organization.
Properties may be eligible for listing in the NRHP if they possess significance at the national, state, or
local level in American history, architecture, archaeology, engineering, or culture. For a property to be
considered a historic property, it must meet basic criteria and retain the historic integrity of those features
necessary to convey its significance. To convey significance, historic properties will always possess
several, and usually most, of the following seven aspects of integrity: location, design, setting, materials,
workmanship, feeling, and association. The passage of time may require re-evaluation of historic
properties to reaffirm the original National Register status. Effects on historic properties may include
both direct effects and visual or other indirect effects. An effect on a historic property is cognizable under
the NHPA if it alters a character-defining feature of eligibility.
More than 80,000 properties are listed in the NRHP. Almost every county in the United States has at least
one property listed in the NRHP. Because of the broad scope and location of the potential ASR Program
projects, the description of site-specific cultural resources is beyond the scope of this PEA. Proponents of
individual actions subject to the ASR Program are required to identify historic properties and assess
effects on those properties pursuant to procedures set forth in the Nationwide Programmatic Agreement
for the Review of Effects on Historic Properties for Certain Undertakings Approved by the FCC
(FCC
2004). Site-specific conditions identified in this review would be discussed in project-specific NEPA
documentation, if required.
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Affected Environment
4.8 OTHER VISUAL AND AESTHETIC RESOURCES
Visual and aesthetic resources are the natural and man-made features that constitute an area’s visual
character. They include the landscape character (what is seen), visual sensitivity (human preferences and
values regarding what is seen), scenic integrity (degree of intactness and wholeness in landscape
character), and landscape visibility (relative distances of seen areas) of a geographically defined
viewshed. Visual resources generally refer to the urban environment, whereas aesthetic resources
typically refer to natural and scenic areas.
The visual and aesthetic characteristics of a project site depend on whether the area is a remote, rural, or
urban setting. In a remote or rural setting, the landscape tends to be dominated by naturally occurring
landforms and vegetation. Although naturally occurring visual resources dominate rural areas, some signs
of human activity are likely to be present and may also contribute to the aesthetics. Examples include
houses, agricultural fields, fences, barns, highways, communications towers, power lines, and lighthouses.
Remote areas may have no visible man-made structures. Within an urban setting, natural features that
may be present include parks and other green spaces, waterfalls, and ponds.
Effects to aesthetic and visual resources deal broadly with the extent to which development contrasts with
the existing environment, architecture, historic or cultural setting, or land use. Evaluating the visual and
aesthetic qualities of an area is a subjective process because the value an observer places on specific
landscape features varies depending upon the values and attitudes of the observer. Visual intrusions may
also have an impact on some traditional cultural practices. Regardless of the subjective nature of assessing
visual and aesthetic qualities of an area, landforms, water surfaces, vegetation, and man-made features
can generally be considered characteristic of an area if they are inherent to the composition and function
of the landscape.
There are no general Federal statutory or regulatory requirements that protect visual resources and
aesthetics, but state, regional, or local requirements may apply. The National Scenic Byways Program
(P.L. 105–178, 23 U.S.C. §162) protects the viewsheds of national scenic byways, and state laws
similarly protect state-designated scenic byways. Consultation with the National Park Service may be
required for potential impacts on the visual resources in National Parks. Section 6(f) of the Land and
Water Conservation Fund Act (16 U.S.C. §460) protects visual resources in some outdoor recreation sites
and facilities. In addition, as discussed in Section 4.7, Section 106 of the NHPA requires evaluation of
visual impacts on historic properties.
4.9 ECONOMICS
Tower proponents incur costs for the planning, permitting, construction, and operation and maintenance
of their structures. Environmental compliance costs may include site selection and feasibility studies,
environmental studies, NEPA documentation, agency coordination and consultation, and permitting.
NEPA documentation requirements are driven by the ASR regulations.
In 2009, 67 tower registrations required an EA; and in 2010, 69 tower registrations required an EA. In
2011, that number increased to 132, but only 42 of these EAs were for towers taller than 200 feet (61
meters). The Bureau estimates that under the current ASR program, EA preparation for a tower typically
costs between $5,000 and $15,000 (with exceptional cases costing up to $25,000), depending on the
complexity of issues and resources to be addressed. A typical EA takes approximately 45 to 50 days to
process from receipt until issuance of a FONSI. To date, no proposed tower subject to the ASR program
has required preparation of an EIS, most likely due to the willingness of ASR applicants to amend their
tower proposals (in either location or design) to reduce, minimize, or eliminate environmental impacts
and thereby obtain a FONSI.
Costs of tower structures are generally higher for self-supported lattice towers when compared to towers
of similar height that would be supported with guy wires. In particular, the material expense for a self-
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Affected Environment
supported lattice tower is typically more than for a guyed tower of comparable height because more steel
is used; foundations also cost more for self-supported lattice towers than for guyed towers because lattice
towers are usually larger in cross section and require more concrete. Because more material (steel and
concrete) is used, on-site construction time for self-supported lattice towers is also generally longer than
for guyed towers, which increases the labor cost of self-supported lattice towers. On the other hand, the
cost of land will typically be higher for a guyed tower than for a lattice tower. For example, a 250-foot
(76-meter) guyed tower may require more than 3 acres (1.2 hectares) of land, whereas a 250-foot (76-
meter) self-supported tower typically requires less than 1 acre (0.4 hectare). Monopole towers are often
more expensive to construct than self-supported lattice towers of similar height because of material costs.
A monopole tower is one large steel tube whereas a lattice tower is comprised of many smaller steel
tubes. However, the time to construct for a monopole is usually shorter than for a lattice tower. It is not
relevant to compare the costs of monopole towers against guyed towers because monopole towers are
generally less than 200 feet (61 meters) and guyed towers are usually much taller.
4.10 RADIO FREQUENCY RADIATION
Radiofrequency (RF) radiation (radio waves) is defined as electromagnetic waves (generated by the
oscillation of a charged particle) with a wave frequency (the number of waves per unit time) in the RF
range, which is between 10 kilohertz and 300,000 megahertz (MHz). Radio waves are radiated by
antennas used for several applications, including cellular communications, radio and television
broadcasts, two-way radio communications, and others. Antennas are often located atop hills, towers,
rooftops, and other elevated structures to enhance their operating range.
Although RF radiation does not present the same type of health hazards as “ionizing” radiation sources
such as X-rays and gamma rays (which can cause molecular changes that may result in significant genetic
damage), high intensities of RF radiation can be harmful. Similar to microwaves (which fall within the
RF range), RF radiation has the ability to heat biological tissue rapidly, resulting in tissue damage, which
is known as a “thermal” effect. The extent of this heating depends on several factors, the most important
of which are the intensity and frequency of RF radiation. Others include the size, shape, and orientation of
the exposed object, duration of exposure, environmental conditions, and efficiency of heat dissipation
(FCC 1999).
In 1996, the FCC adopted guidelines for human exposure to RF radiation, which were based on criteria
developed by the National Council on Radiation Protection and Measurement in 1986 and on standards
developed by the American National Standards Institute and the Institute of Electrical and Electronics
Engineers, Inc. in 1992. These exposure guidelines are based on the threshold level at which harmful
biological effects may occur, which depends on electric and magnetic field strength and power density.
The FCC guidelines are most stringent for the frequency range from 30 to 300 MHz, the range in which
the human body absorbs RF radiation most efficiently. Maximum permissible exposure (MPE) limits
were developed for two categories. The first category, which affects the occupational population, applies
to human exposure to RF fields when people are exposed due to their employment, have been made fully
aware of the potential for exposure, and can exercise control over their exposure. The second category,
which affects the general population, applies to human exposure to RF fields when the general public may
be exposed or when personnel exposed because of their employment may not be aware of exposure or
cannot exercise control over the exposure. A significant impact would occur if exposure limits to the
occupational or general population exceeded the MPE limits.
Because the likelihood of exceeding the MPE limits depends heavily on operating power, the FCC
exempts many lower power operations from routine evaluation for compliance with these limits. For
example, the FCC requires that tower-mounted installations for cellular telephone services be evaluated
only if antennas are mounted lower than 32.8 feet (10 meters) above the ground and the total power of all
channels being used is more than 1,000 watts of effective radiated power (2,000 watts in some frequency
ranges). By contrast, commercial radio and television stations may operate at up to millions of watts of
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Affected Environment
effective radiated power. Therefore, all radio and television broadcast antennas must be evaluated for
compliance with the RF exposure limits. Due to large populations and the numerous communication
sources (e.g., radio stations, cellular telephones, CB radios) present in urban areas, radio wave exposure is
higher in areas where the majority of FCC-registered antenna sites currently exist. Due to relatively small
populations and fewer emitting sources, radio wave exposure is generally lower in rural areas and areas
where undeveloped sites may be selected for new towers.
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Environmental Consequences

SECTION FIVE

ENVIRONMENTAL CONSEQUENCES

This chapter presents the potential impacts that the alternatives described in Chapter 3 (No Action
Alternative, Alternative 1, and all options of Alternative 2) may have on the resources described in
Chapter 4. It is important to note that the ASR program is national in scope, and the environmental
impacts of each individual tower may vary greatly depending on local conditions. Therefore, this PEA
does not assess the environmental impacts of any particular tower. Rather, the PEA focuses on the broad,
programmatic impacts of the ASR program in a national context. The impacts of individual towers are
discussed as a means of establishing context for the programmatic assessment. In addition, the PEA
considers in Chapter 7 whether the FCC’s processes, including its criteria for determining which towers
are categorically excluded and which require an EA, ensure that potentially significant impacts of
individual towers will be identified and considered. If an individual tower may have potentially
significant environmental impacts, those impacts would be addressed in an EA prepared for that tower.
For each resource addressed in Section 5.4 below, the No Action Alternative establishes the baseline of
existing conditions in the future if towers continue to be constructed and registered under the ASR
program as it currently exists. The discussion then assesses impacts from the ASR program under each of
the alternatives considered. In Chapter 7, the PEA makes findings based upon these assessments as to
whether the impacts are significant.
5.1 CATEGORIES OF IMPACTS
Impacts (or effects) can be categorized in a variety of ways, such as by description (beneficial or adverse)
and duration (short- or long-term). NEPA requires consideration of all categories of impacts that apply to
a proposed action and assessment of direct, indirect, and cumulative impacts.

Direct impacts

are caused by the action and occur at the same time and place, for example, birds
colliding with towers.

Indirect impacts

are caused by the action and are later in time or removed in distance, but are still
reasonably foreseeable. For example, this includes habitat avoidance by some birds in areas where towers
are constructed or changes in flight patterns due to the presence of towers.

Cumulative impacts

result when the effects of an action are added to or interact with other effects in a
particular place and within a particular time. In evaluating the cumulative impacts of an action, an agency
considers the total effects on a resource, ecosystem, or human community of that action and all other
activities affecting that resource, no matter what entity (Federal, non-Federal, or private) is taking the
actions. Cumulative impacts involve the combined, incremental effects of human activity. In accordance
with NEPA and to the extent reasonable and practical, this PEA considers the combined effects of the No
Action Alternative, Alternative 1, and all options of Alternative 2 with other actions that may affect the
resources identified. For example, other potential impacts on birds include collisions with other vertical
structures, predation by cats, and population changes due to climate change. This PEA also considers
under cumulative impacts the combination of the environmental effects of future towers to be registered
under the ASR program with the ongoing effects of existing registered towers. Cumulative impacts are
addressed in Chapter 6.
5.2 SIGNIFICANCE OF IMPACTS
According to CEQ regulations (40 CFR 1508.27), significance under NEPA requires consideration of
both context and intensity, as discussed in this chapter and in Chapter 6. Chapter 7 of this PEA discusses
whether any of the ASR Program’s environmental impacts are classified as significant.
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Environmental Consequences
5.2.1 Context
The significance of an impact must be analyzed in several contexts such as society as a whole (human,
national), the affected region, the affected interests, and the locality. Significance varies with the setting
of the proposed action. Both short- and long-term effects are relevant.
The ASR Program is national in scale and therefore has the potential to impact resources throughout the
United States, its territories, and the District of Columbia. The projects that would be reviewed and
potentially approved for registration under the ASR Program would be implemented in geographically
diverse areas (both urban and rural), as well as previously disturbed and undisturbed sites. Because of the
wide variety of natural and manmade environments that may be affected by the ASR Program, and the
complexity of resources potentially affected, it is not possible to provide a detailed comprehensive
description of resource impacts at individual sites in this PEA. Therefore, Chapter 5 characterizes
resource impacts in general terms and identifies those resources that may require additional site-specific
analysis of impacts.
For purposes of evaluating the impacts of the ASR program as a whole, as addressed in this PEA, the
relevant context is generally national or international in scope. In addition, this PEA considers whether
project-specific EAs may be necessary to address the potential effects of individual towers. In such
project-specific EAs, the discussion of impacts will be more local in context.
5.2.2 Intensity
Intensity refers to the severity of impact. The following should be considered in evaluating intensity:
1. Impacts that may be both beneficial and adverse. A significant effect may exist even if the
Federal agency believes that on balance the effect will be beneficial.
2. The degree to which the proposed action affects public health or safety.
3. Unique characteristics of the geographic area such as proximity to historic or cultural resources,
park lands, prime farmlands, wetlands, wild and scenic rivers, or ecologically critical areas.
4. The degree to which the effects on the quality of the human environment are likely to be highly
controversial.
5. The degree to which the possible effects on the human environment are highly uncertain or
involve unique or unknown risks.
6. The degree to which the action may establish a precedent for future actions with significant
effects or represents a decision in principle about a future consideration.
7. Whether the action is related to other actions with individually insignificant but cumulatively
significant impacts. Significance exists if it is reasonable to anticipate a cumulatively significant
impact on the environment. Significance cannot be avoided by terming an action temporary or by
breaking it down into small component parts.
8. The degree to which the action may adversely affect districts, sites, highways, structures, or
objects listed in or eligible for listing in the National Register of Historic Places or may cause loss
or destruction of significant scientific, cultural, or historical resources.
9. The degree to which the action may adversely affect an endangered or threatened species or its
habitat that has been determined to be critical under the Endangered Species Act of 1973.
10. Whether the action threatens a violation of Federal, state, or local laws or requirements imposed
for the protection of the environment.
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Environmental Consequences
Neither the CEQ regulations nor the FCC regulations provide definitions of the thresholds of impact.
Therefore, this PEA uses impact threshold definitions that take into consideration the characteristics of
communications towers. Four levels are used to describe the intensity of direct and indirect impacts on
each resource, as well as cumulative impacts discussed in Chapter 6, for each alternative:
·
Negligible – The impact is barely perceptible or measurable and remains localized and confined.
For example, excavation required to construct a tower would cause surficial ground disturbance,
which would impact soils. However, because the typical footprint of disturbance for construction
of a tower is small, adverse impacts to soils would be barely perceptible and confined to the
footprint of the tower and compound.
·
Minor – The impact is slight but perceptible and measurable and remains localized and confined.
For example, construction of a tower in or near a wetland may cause a perceptible change in the
wetland’s size, integrity, or continuity. However, the change would be slight and the wetland’s
ability to perform vital functions, such as filtering pollutants or providing habitat for wildlife,
would not be affected.
·
Moderate – The impact is readily apparent and sufficient to cause a change in the character-
defining features of a resource. It generally does not affect the resource’s viability. For example,
clearing 1 acre (0.4 hectare) of trees would cause a clearly detectable change in a forest
community and may have an appreciable impact on that community. This could include changes
in the abundance, distribution, or composition of vegetation communities, but would not include
changes that would affect the viability of plant populations in the forest.
·
Major – The impact results in a substantial and highly noticeable change in character-defining
features or involves an individually important feature of a resource. A major impact may, but
does not necessarily, affect the resource’s viability. For example, an impact that results in the
deaths of large numbers of individual wildlife would be highly noticeable and constitute a major
impact.
5.2.3 Significance Determination
Once the relevant context has been identified and an impact has been determined to be negligible, minor,
moderate, or major, a determination of the impact’s significance must be made, based on the requirements
in 40 CFR 1508.27. Three levels of impact can be identified:
·
No Impact – No impact is anticipated.
·
No Significant Impact – An impact is anticipated, but the impact does not meet the
intensity/context significance criteria for the specified resource.
·
Significant Impact – An impact is anticipated that meets the intensity/context significance criteria
for the specified resource.
The levels of these impacts and their specific definitions vary based on the resource that is being
evaluated. For example, what constitutes a significant impact may be different for wetlands when
compared to visual resources, both in terms of the relevant context and the intensity of effects.
Negligible, minor, and moderate impacts are generally not significant. Negligible and minor impacts are
not significant because their intensity is only barely or slightly perceptible within a localized and confined
context. Moderate impacts are usually not significant because they are not highly noticeable and do not
involve individually important features. However, a moderate impact may be significant if its importance
is magnified by the context in which it occurs.
Major impacts are often significant, but are not necessarily so when considered in context. For instance, a
major impact would be significant if it threatens the viability of a population so that the population may
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Environmental Consequences
not recover. For example, the deaths of many individual members of a wildlife population, while a major
impact, may not constitute a significant impact in the context of a much larger total population that is
subject to far greater forces. As explained in Chapter 7, the ASR Program for this reason does not have a
significant impact at the national level on migratory birds, although there may be significant impacts on
local populations at individual sites depending on the alternative selected.
Findings regarding the significance of the ASR Program’s impacts on the resources considered in this
PEA are made in Chapter 7, based on the relevant context and assessments of intensity presented in this
chapter, and the assessment of cumulative impacts in Chapter 6.
5.3 ASSUMPTIONS
Impacts may result during both the construction of a tower and the operational phase after the tower is
constructed. The construction of a tower and its associated compound, including any supporting
structure(s), access road(s), or installation of utilities, may cause impacts resulting from heavy equipment
operation, vegetation clearing, and ground-disturbing activities. In general, impacts from construction of
towers are negligible or minor, given the relatively small footprints of the towers; in most instances,
construction impacts are also temporary.
Once a tower is constructed, it may also cause impacts to resources, especially birds and visual
quality/aesthetics, due to the extension of a structure into the airspace. Operational impacts can be
ongoing as long as the tower is in place.
The following assumptions have been made with respect to future tower construction under the No Action
Alternative, Alternative 1, and all options of Alternative 2.
5.3.1 Tower Construction Footprints
A typical project site size and area of ground disturbance (vegetation clearing, impervious surface, etc.)
for a 200-foot (61-meter) monopole or self-supported, unguyed tower is approximately 1 cleared acre (0.4
hectare). Guyed towers require a much larger project site size (approximately 30 or more acres [12.1
hectares] for a 1,000-foot [305-meter] guyed tower). However, although the project site is much larger for
a guyed tower, the project site size is dictated by the guy wire array, which extends out from the tower
structure. The actual ground disturbance for a guyed tower is not much greater than for an unguyed
tower, since the additional ground disturbance required for the guy wire anchor points is small.
5.3.2 Number of Towers
It is assumed that a similar number of towers would be built under the No Action Alternative, Alternative
1, and all options of Alternative 2, because none of the alternatives would reduce the demand and need for
towers. It is also assumed that under all alternatives, communications providers would first seek to
collocate their antennas on existing towers or other structures to reduce costs and time involved in
receiving environmental approvals and constructing new towers.
Although there is reason to think that the number of new registered towers constructed may continue its
recent trend of decline, this PEA conservatively assumes that construction will occur at a pace similar to
the median of the last six years. On this basis, it is estimated that approximately 2,800 towers per year
will be constructed during the 10-year time period addressed in this PEA (see Section 4.2.4).
5.3.3 Tower Location
It is assumed that tower location is driven by the technological requirements and landscape conditions in a
specific area. Because the consideration of areas important to migratory birds is similar under the No
Action Alternative, Alternative 1, and Option C of Alternative 2, it is assumed that there likely would be
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Environmental Consequences
no substantial difference in the locations of towers that would be built under each of these alternatives. It
is anticipated that under Option B, applicants would attempt where possible to site towers that are over
450 feet (137 meters) tall, have guy wires, or use red steady lighting outside of coastal zones, ridgelines,
bird staging areas, colonial nesting sites, and WHSRN sites, and to site all towers away from important
Bald and Golden Eagle use areas, to avoid having to prepare an EA. Also, under both Option A and
Option B some proposed towers may be moved out of avian high use areas as a result of the
environmental review process. However, the degree to which towers could be placed to avoid these areas
would likely be limited. For example, it is likely that many towers proposed in coastal zones could not be
moved out of the coastal zone, since these areas are typically large. Also, moving a tower off a ridgeline
may result in the need for a taller tower or multiple towers, which may offset the potential beneficial
impacts to migratory birds.
5.3.4 Tower Height
It is assumed that tower height is driven by the technological requirements and landscape conditions in a
specific area. As a result, it is assumed that there likely would be no substantial difference in the heights
of towers that would be built under the No Action Alternative, Alternative 1, and all options of
Alternative 2. It is possible that in some instances tower owners may choose to construct towers less than
450 feet (137 meters) tall because of the increased level of NEPA documentation and review required for
taller towers under Alternative 2 Option C and, in some locations, Option B. However, in many
instances, particularly for broadcast towers, it is unlikely that such a tower could be reduced appreciably
in height and still be able to meet service coverage requirements. Under all options of Alternative 2,
some proposed towers may also be reduced in height as a result of the environmental review process.
Again, however, the ability appreciably to reduce tower heights is in most instances likely very limited.
Furthermore, the use of shorter towers may mean that more towers will be required to meet service
requirements.
5.3.5 Support System
It is assumed that the use of guy wires instead of a self-supported design is driven by the structural
requirements at a specific location, as well as economic considerations and local regulations. As a result,
it is assumed that there likely would be at most a limited reduction in the number of towers proposed and
built using guy wire supports under Alternative 2 Options A and B when compared to the No Action
Alternative and Alternative 1. It is possible that in some instances tower owners may choose to build
towers without guy wires because of the increased level of NEPA documentation and review required for
towers with guy wires in some locations under Alternative 2 Option B. Also, in some instances the
environmental review process may result in the elimination of guy wires under Alternative 2 Options A
and B. However, in many instances the elimination of guy wires from proposed towers will be
technically or economically infeasible. It is assumed that there likely would be no substantial difference
in tower support systems under the No Action Alternative, Alternative 1, and Option C of Alternative 2
because it is ordinarily not feasible to avoid the use of guy wires on a tower over 450 feet (137 meters)
tall.
5.3.6 Lighting Scheme
For the No Action Alternative, no changes to lighting schemes would occur because the current FAA
lighting circular would still apply to all existing and future towers. For Alternative 1, revisions to the
FAA lighting circular are assumed to occur, so that no new towers will use red steady-burning lights and
existing tower owners may choose to remove or turn off red steady-burning lights. For all options of
Alternative 2, the PEA considers lighting effects on migratory birds under two mutually exclusive
alternatives: (1) the FAA does not revise its lighting circular, so that the only permitted alternatives to
lighting styles employing red steady-burning lights are lighting styles employing white strobe lights
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Environmental Consequences
(which have their own environmental concerns); and (2) the FAA revises its lighting circular, so that no
new towers will use red steady-burning lights and existing tower owners may choose to remove or turn
off red steady-burning lights.
Given the increased level of NEPA documentation and review required under Alternative 2 Option B for
red steady-burning lighting schemes when proposed in conjunction with a location on a ridgeline or
within a coastal zone, bird staging area/colonial nesting site, or WHSRN site, it is assumed that if the
FAA does not revise its lighting circular, fewer towers would be proposed and built using red steady-
burning lighting schemes under Alternative 2 Option B when compared to the No Action Alternative.
Also, the environmental review process would likely result in some new towers not using red steady
lights under Alternative 2 Option A and, for towers over 450 feet (137 meters) in height, Option C.
However, the option to avoid red steady-burning lighting may not be available in many instances due to
zoning or other restrictions on or community opposition to white strobe lights. Therefore, the reduction
in the use of red steady lights would be less under any option of Alternative 2 without revisions to the
FAA lighting circular than under Alternative 1 or any option of Alternative 2 with revisions to the FAA
lighting circular.
Under Alternative 1 and all options of Alternative 2, it is assumed that revisions to the FAA lighting
circular would result in some tower owners removing or turning off red steady-burning lights on existing
towers.
5.4 IMPACTS BY RESOURCE
The anticipated impacts from continuation of the ASR Program (No Action Alternative), the existing
ASR Program with FAA lighting changes (Alternative 1), and modifications to the ASR Program
(Alternative 2 Options A, B, and C) for the resources described in Chapter 4 are presented below.
5.4.1 Water Resources
Evaluation criteria for impacts on water resources are based on water quality, use, and associated
regulations. Adverse impacts on water resources would occur if the project:
·
Violates a Federal, state, or local law or regulation adopted to protect water resources.
·
Causes irreparable harm to human health, aquatic life, or beneficial uses of aquatic ecosystems.
·
Degrades surface water quality.
·
Reduces water availability or supply to existing users.
5.4.1.1 Surface Water

No Action Alternative


Under the No Action Alternative, impacts to surface waters would be expected to stay the same.
Construction of new towers would be expected to result in short-term and long-term negligible to minor
adverse impacts on surface water resources, due to the potential for construction activities to cause
increased sediment runoff into surface waters and the creation of permanent impervious surfaces at the
project site. The magnitude of adverse impacts would depend on the specific location and the construction
requirements of that location. The current ASR Program requires applicants to prepare an EA for towers
that would cause a significant change in surface features, including water diversion.
Construction of the tower and equipment building would typically result in the disturbance of no more
than several acres, and therefore would be expected to result in negligible to minor adverse impacts to
surface waters from sedimentation. Construction of any additional roads and utilities that might be
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Environmental Consequences
required could result in minor adverse impacts on surface water resources from sedimentation, depending
on site-specific soil conditions, topography, and surface water bodies at any given location.
Construction of new tower facilities creates a small amount of permanent impervious surfaces that could
slightly increase the quantity of storm water runoff, decrease storm water quality, and reduce the amount
of groundwater that infiltrates underlying aquifers. Most towers would likely only require the tower and
equipment building to be permanently impervious, which would have a long-term, negligible adverse
impact on surface water resources due to storm water runoff. The length of road and road material needed
at any one site is variable and these factors may contribute to impacts on surface waters. Construction of
an access road adjacent to a stream would have the potential to introduce roadway contaminants directly
into surface water resources, as well as increase the potential for flash flooding downstream. At most
sites, these kinds of impacts would be negligible.
At some locations, the creation of access roads may require minor modifications of stream channels, such
as installing a culvert or hardened stream crossing. These kinds of modifications could result in minor
long-term adverse impacts on surface waters, such as increased potential for flooding. The magnitude of
the impact would depend on the site-specific location. Under FCC regulations, diversion of surface water
would require the project applicant to prepare an EA for the project.
The use of construction staging areas would result in short-term negligible adverse impacts. It is not
expected that staging areas would be cleared, graded, or permanently altered, although minor soil
disturbance could occur as a result of vehicle traffic.
Towers may require a backup generator, most likely powered by diesel or liquid propane stored in a tank.
Storage of fuels on site has the potential to introduce contamination into surface water. The potential that
a spill or leak would occur is small, and the amount of fuel onsite would not be sufficient to cause
widespread contamination. Spills or leaks would likely result in short-term negligible to minor adverse
impacts on surface water resources. Surface water or areas that have karst terrain would be more
susceptible to adverse impacts in the event of a spill or leak.

Alternative 1


Alternative 1 would be expected to have similar impacts on surface water resources as described under
the No Action Alternative.

Alternative 2 Options A, B, and C


Changes to the ASR Program proposed under all options of Alternative 2 would be expected to have
similar impacts on surface water resources as described under the No Action Alternative.
5.4.1.2 Wetlands and Waters of the United States
ASR Program projects affecting wetland areas would require site-specific evaluation and agency
consultation to identify and delineate wetlands and WOUS, determine permitting requirements, and
develop mitigation measures if required. In addition, wetland areas may contain riparian zones that are
important habitats to migratory birds; these are discussed in Section 5.4.3.3.

No Action Alternative


Under the No Action Alternative, impacts to wetlands and WOUS would be expected to stay the same.
The current ASR Program requires applicants to prepare an EA for proposed towers that would cause a
significant change in surface features, including wetland fill. Construction of new towers would be
expected to result in short-term and long-term negligible to minor adverse impacts on wetlands and
WOUS, due to the potential for construction activities to disturb wetlands or WOUS, cause increased
sediment runoff into these resources, and create permanent impervious surfaces at the project site. The
magnitude of adverse impacts would depend on the specific location and the construction requirements of
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Environmental Consequences
that location, but in any event should be no greater than negligible to minor due to the small size of the
areas to be disturbed or covered with impervious surfaces. Due to the EA requirement, any wetland fill
would require approval from the USACE.

Alternative 1


Alternative 1 would be expected to have similar impacts on wetlands and WOUS as described under the
No Action Alternative.

Alternative 2 Options A, B, and C


Changes to the ASR Program proposed under all options of Alternative 2 would be expected to have
similar impacts on wetlands and WOUS as described under the No Action Alternative.
5.4.2 Floodplains
ASR Program projects require site-specific evaluation and, where appropriate, agency consultation to
determine whether a project is within the floodplain and develop mitigation measures if required. The
FCC’s practice is to require that an EA prepared for a new tower project in a floodplain include a building
permit showing that the structure is at least 1 foot (0.3 meter) above the base flood elevation.
Floodplains may also contain riparian zones that are important habitats to migratory birds. These are
discussed in Section 5.4.3.3.

No Action Alternative


Under the No Action Alternative, impacts to floodplains would be expected to stay the same. The current
ASR Program requires applicants to prepare an EA for towers proposed in floodplains. Construction of
new towers would be expected to result in short-term and long-term negligible to minor adverse impacts
on floodplains, due to the potential for construction activities to cause slightly increased floodwater flows
downstream of the project site.

Alternative 1


Alternative 1 would be expected to have similar impacts on floodplains as described under the No Action
Alternative.

Alternative 2 Options A, B, and C


Changes to the ASR Program proposed under all options of Alternative 2 would be expected to have
similar impacts on floodplains as described under the No Action Alternative.
5.4.3 Biological Resources
ASR Program projects affecting biological resources would require site-specific evaluation to identify
specific biological resources that may be affected by new tower projects. Impacts are discussed below in
general terms.
5.4.3.1 Vegetation and Wildlife (Other than T&E Species/Critical Habitat and Migratory

Birds)


Construction of new towers and associated compounds would affect vegetation and wildlife due to
construction disturbance. The typical footprint of disturbance for towers is small. Although guyed towers
have a much larger overall footprint than self-supported structures, the actual area of disturbance is not
that much greater because, other than the tower and compound, only small areas need to be excavated to
place concrete footers for the guy wire arrays. Vegetation such as shrubs and trees may also be cleared in
other portions of the site for construction equipment staging areas or access roads.
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Environmental Consequences

No Action Alternative


Under the No Action Alternative, impacts to vegetation and wildlife would be expected to stay the same.
Construction of new towers would be expected to continue to cause short- and long-term negligible to
minor adverse impacts on vegetation and wildlife due to removal and disturbance of vegetation, some
direct mortality to less mobile wildlife, habitat fragmentation and removal, and introduction of non-native
invasive species. The current ASR Program requires applicants to prepare an EA for proposed towers that
would have a significant effect on surface features, including deforestation. The current ASR Program
also requires preparation of an EA for towers to be constructed in wilderness areas and wildlife preserves,
as well as wetlands and floodplains.
Potential adverse impacts on vegetation and wildlife associated with site development would vary
depending on the characteristics of the tower location and could include direct long-term impacts
associated with removal of vegetation, as well as indirect short- and long-term impacts associated with
direct mortality to some less mobile wildlife (reptiles, amphibians, small mammals) and habitat
fragmentation or removal during, or as a result of, site development. Placement of a tower in an urbanized
environment would have less potential for adverse impacts on vegetation and wildlife than placement in
an undeveloped area.
Development in fields, successional habitats, or fallow agricultural land would be expected to affect
vegetation characterized by herbaceous species, shrubs and young tree species; in forested habitats, large
trees, saplings, and associated understory vegetation would be affected. Wildlife dependent on these
habitats would also be affected. Some indirect damage to trees and understory vegetation would also be
expected to occur as a result of damage to root systems, soil compaction, and landscape modification
associated with the use of heavy construction equipment for site development.
Removal and disturbance of vegetation to accommodate site development has the potential to introduce
and spread non-native invasive species of vegetation due to disturbance of native habitats and
introduction of species from seeds carried in on construction equipment used at other sites. Spread of non-
native invasive species in the area of tower development could result from disturbance which could allow
these species to become established from seed stock on the site or in adjacent habitats. Invasive species
could also be introduced through construction equipment brought to the site from other locations. The
establishment and spread of common reed is of particular concern in wetland and coastal areas; it can
aggressively take over areas previously characterized by native plants. In terrestrial environments, species
such as tear-thumb and porcelain berry can quickly dominate areas of native vegetation. Use of standard
best management practices to clean equipment that is moved from one area to another can help reduce the
spread of non-native invasive species.

Alternative 1


Alternative 1 would be expected to have similar negligible to minor impacts on vegetation and wildlife as
described under the No Action Alternative.

Alternative 2 Options A, B, and C


Changes to the ASR Program proposed under all options of Alternative 2 would be expected to have
similar impacts on vegetation and wildlife as described under the No Action Alternative. Because any
adverse impacts under Alternative 2 would be negligible to minor, it is unlikely that the preparation and
review of additional EAs would be of more than minor benefit.
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Environmental Consequences
5.4.3.2 T&E Species and Critical Habitat
Impacts on T&E species were classified using the following terminology, as defined under the ESA:
·

No effect

– would be determined if a proposed action would not affect a listed species or
designated critical habitat.
·

May affect/not likely to adversely affect

– would be determined if impacts on listed species are
discountable (i.e., extremely unlikely to occur and not able to be meaningfully measured,
detected, or evaluated) or completely beneficial.
·

May affect/likely to adversely affect

– would be determined when an adverse effect on a listed
species occurs as a direct or indirect result of proposed actions and the effect is neither
discountable nor completely beneficial.
·

Likely to jeopardize proposed species/adversely modify critical habitat

– would be
determined if the USFWS identified situations in which actions could jeopardize the continued
existence of a listed species or adversely modify habitat critical to a species within or outside of
the project area.

No Action Alternative


Under the No Action Alternative, impacts to T&E species and critical habitat would be expected to stay
the same. The current ASR Program requires applicants to prepare an EA for towers that may affect
listed T&E species or critical habitats, or are likely to jeopardize the continued existence of proposed
T&E species or result in destruction or adverse modification of proposed critical habitats. Towers that
would not affect these resources may be categorically excluded from preparation of an EA, which would
allow applicants to obtain FCC approval more quickly, thereby saving the applicant time and money.
Under the No Action Alternative, a determination of whether the proposed construction or operation of a
new tower is likely to adversely affect a federally listed T&E species or critical habitat would be based on
a site-specific review of information available from USFWS. If it is determined that there is potential for
adverse impacts on a threatened or endangered species, the applicant or the FCC would need to
coordinate with the appropriate USFWS office. Through this coordination, the impacts may be reduced
to no effect or not likely to adversely affect. If it is not possible to reduce the impacts to no effect or not
likely to adversely affect, the FCC and USFWS would enter into formal consultation resulting in a
Biological Opinion and mitigating measures, and an EA would be required. Similarly, if it is determined
that a project is likely to jeopardize the continued existence of proposed T&E species or result in
destruction or adverse modification of proposed critical habitats, the applicant or the FCC would
coordinate with the appropriate USFWS office, and an EA would be required if the likely jeopardy or
destruction or adverse modification of habitat cannot be avoided.
In addition, tower operators currently attempt to site new towers outside of areas that might affect listed
species or critical habitat to avoid the potential for costly project delays due to agency coordination
requirements.
The FCC has recently entered into programmatic consultation with USFWS under Section 7(a)(1) of the
ESA. This consultation is expected to result in an evaluation of the degree to which the ASR Program
contributes to furthering the purposes of the ESA, along with possible recommendations to improve or
enhance this contribution, as well as a description of any subsequent consultation that may be required
between USFWS and the FCC at a less aggregated regional or local scale.
The FCC’s procedures for implementing the ESA ensure that adverse effects to T&E species will be
mitigated if they cannot be avoided. Due to the FCC’s requirements to coordinate with the USFWS and to
prepare EAs in appropriate cases, the No Action Alternative is anticipated to have short- to long-term
negligible to minor impacts to threatened and endangered species and critical habitat.
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Alternative 1


Alternative 1 would be expected to have similar impacts on T&E species and critical habitat as described
under the No Action Alternative.

Alternative 2 Options A, B, and C


Changes to the ASR Program under Alternative 2 Options A, B, and C would be expected to have similar
impacts on T&E species and critical habitat as described under the No Action Alternative.
5.4.3.3 Migratory Birds

Direct Effects

Direct effects on migratory birds from towers consist of mortality caused by collisions with the tower
structure and guy wires.

Data Limitations and Uncertainty


There are approximately 50 studies in the peer-reviewed scientific literature that have documented bird
kills at towers. Most of these studies examine bird deaths at only one or a few towers. Although 96,039
towers were identified in the FCC database as having a construction date as of February 1, 2012 (FCC
2012), the number of studies from which to draw conclusions is limited.

Overview


Although towers of all types have the potential to kill some birds, collision risk is known to increase with
the height of the tower, with the addition of guy wire supports and with the amount and type of lighting
(Manville 2001). Towers that exceed 984 feet (300 meters) cause 69 percent of mortality to migratory
birds, and 84 percent of mortality is caused by towers that exceed 490 feet (149 meters) (Longcore 2012
in press). Other characteristics of towers that cause disproportionate amounts of mortality to migratory
birds include the use of red steady-burning lights at night (Gehring et al. 2009), the use of guy wires
(Gehring et al. 2011), location near wetlands or other natural habitat types where birds gather together,
location in major songbird migration corridors, and location in areas that have a history of inclement
weather, especially during spring and fall migrations (Manville 2001). Mortality is significantly greater at
taller towers with red steady-burning lights and guy wires, and there is little evidence of multiple bird
deaths at shorter tower heights with flashing lighting schemes and absence of guy wires (Kerlinger et al.
2010, Gehring et al. 2011). Inclement weather including fog, overcast conditions and precipitation is
typically a contributing factor to larger-scale mortality events (Cochran and Graber 1958, Caldwell and
Wallace 1966, Avery et al. 1976).
In September 1948, a 450-foot (131-meter) radio tower in Baltimore, Maryland was the first
communications tower documented to kill migratory birds (Aronoff 1949). The first long-term study of
the impact of a communications tower on birds was begun in 1955 by the Tall Timbers Research Station
in northern Florida. During the 25-year study, 42,384 birds representing 189 species were documented as
killed (Crawford and Engstrom 2000). Over the course of a 38-year study at one television tower in Eau
Claire, Wisconsin beginning in 1957, Kemper collected approximately 121,560 birds representing 123
species (Kemper 1996). This study includes the all-time record for most birds collected during a single-
night tower strike – more than 12,000 birds were collected in a single night in 1963 from the base of the
tower (Kemper 1996). The Wichita Eagle newspaper reported that a large tower kill occurred in western
Kansas on January 22, 1998 when up to 10,000 Lapland Longspurs and several other species died in a
one-night, multi-tower incident.
As discussed in Chapter 4, Manville (2001) estimated annual bird mortality from communications towers
at 4 to 5 million birds and indicated that mortality might actually range as high as 40 to 50 million birds.
The lower end (4 to 5 million) of Manville’s estimate has been frequently cited in other papers as a
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Environmental Consequences
reasonable approximation of bird kills at towers (e.g., Gehring et al. 2009, Gehring et al. 2011). Most
recently, Longcore et al. (2012 in press) have estimated annual avian mortality at towers in the United
States at 6.6 million birds. For purposes of assessing impacts, the Bureau conservatively uses an
estimated annual avian mortality of 6.6 million birds.

Tower Location


Towers in all locations have the potential to kill some birds. However, towers located near wetlands or
other natural habitat types where birds gather together, in major songbird migration corridors, and in areas
that have a history of inclement weather, especially during spring and fall migrations, cause more avian
mortality (Manville 2001). Longcore et al. (2012 in press) have proposed that mortality is not equal
across geographic regions.
As discussed in Section 4.6.3.10, geographic trends in mortality appear to be influenced by the number
and height of towers in an area. Mortality was estimated to be highest in the southeastern United States
where the proportion of tall towers is higher. This mortality is higher than for all of Canada where towers
tend to be fewer and shorter.

Tower Height


Towers of all heights have the potential to kill some birds. However, taller towers present more of a
hazard to migratory birds. While the available data do not permit quantification of the relative hazards of
towers of different heights with any precision, it is clear, for example, that towers that exceed 1,000 feet
(305 meters) AGL cause many times more avian mortality than towers of 450 feet (137 meters) AGL or
less.
Most of the data pertaining to the impact of communications towers on migratory birds is focused on tall,
guyed towers (Weir 1976, Avery et al. 1978, Avery et al. 1980, Trapp 1998, Derby et al. 2002, Johnson et
al. 2002, Gehring et al. 2011). From 1955 through 1983, approximately 44,007 birds were found killed at
a television tower in Leon County, Florida (Crawford and Engstrom 2001). This study was able to isolate
tower height from other factors because the tower was lengthened from its original 670-foot (204-meter)
height to 1,010 feet (308 meters) in 1960, and then shortened to 308 feet (94 meters) in 1989. The
number of birds killed when the tower was reduced to 308 feet (94 meters) was lower by a factor of 32
compared to when the tower was at 1,010 feet (308 meters) (Crawford and Engstrom 2001). Crawford
and Engstrom (2001) suggest that towers approximately 300 feet (94 meters) or shorter in height may not
pose as great a threat of avian mortality as caused by towers 650 feet (200 meters) or greater in height.
They reported no significant difference between the numbers of birds killed when the tower was 670 feet
(204 meters) versus 1,010 feet (308 meters). Longcore et al. (2012 in press), on the other hand, report that
69 percent of the estimated avian mortality from towers is attributable to towers over 984 feet (300
meters) tall, even though the vast majority of towers in the United States are shorter than this height.
They also report that over 84 percent of kills are attributable to towers greater than 490 feet (149 meters)
tall. As described in Section 4.2.2, more than 93 percent of towers in the ASR database are less than 450
feet (137 meters) tall.
In a recent study, Gehring et al. (2011) found that tall towers greater than 1,000 feet (305 meters) in
height and supported by guy wires accounted for 70 times the bird fatalities when compared to medium-
height (380 to 480 feet [116 to 146 meters]) unguyed towers and nearly five times as many as medium-
height guyed towers. Nevertheless, the literature as a whole reflects a certain level of bias in the research,
in that taller towers with large bird kills have been studied more frequently than shorter towers, especially
those less than 200 feet (61 meters).
As shown in Figure 10 below, in general, as tower height increases and encroaches into migratory flight
altitudes, so does a tower’s potential to be a hazard to migrating birds.
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Environmental Consequences

Figure 10: Mean Annual Bird Mortality and Tower Heights

To provide more detailed information (given the scale of Figure 10), the mean annual bird mortality for
towers less than 600 feet (183 meters) is provided below in Figure 11.

Figure 11: Mean Annual Bird Mortality and Tower Heights (<600 feet)

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Environmental Consequences
Reducing proposed tower heights would reduce avian mortality; however, it is likely that most towers
could not be significantly reduced in height and still serve their purpose. To minimize construction costs,
tower owners typically build towers to the minimum height needed. In addition, tower height is
determined primarily by service needs and landscape features; reducing a tower’s height may result in the
need for additional towers, which may offset the potential beneficial impact to birds.

Guy Wires


The presence and number of guy wires and the distance they extend from the tower have been shown to
influence bird mortality (Avery et al. 1977). However, because guy wires are invariably associated with
the tallest towers (out of structural necessity), and because all tall towers require aviation obstruction
marking lights, it is inherently more difficult to separate out the contribution of guy wires alone to the
overall mortality profile of a tower than it is for aviation obstruction lighting, which can be more easily
experimentally manipulated. Nevertheless, Avery et al. (1977) observed at the 1,201-foot (366-meter)
Omega tower in North Dakota (which is stabilized by three sets of five guy wires) that avian mortality on
foggy nights was more concentrated near the tower base, indicating that light attraction may have been
the key factor, whereas mortality on clear nights was more evenly distributed over a broader area beneath
the guy wire array, suggesting that guy wires may have been the key factor in mortality. The
interpretation by Avery et al. (1977) is that on nights with low visibility, migrants are attracted to tower
lights, resulting in collisions with the tower structure itself; whereas on clear nights mortality appears to
be more likely due to collision with wires, other birds, or exhaustion (Longcore et al. 2008, Gehring et al.
2009).
A potentially significant variable regarding guy wires is how far out from the base of the tower they are
anchored. Bierly (1968) suggested that the greater the angle of the wire from the vertical tower, the
greater the amount of exposed wire there is at higher elevations, and hence the greater the probability of
birds colliding with the wires. If that is true, it might therefore be preferable to have the connecting point
for guy wire arrays be as close to the tower base as feasible consistent with structural safety, thereby
minimizing exposed wires at higher elevations. In any case, the presence of an array of guy wires
increases the risk to migratory birds.
Figure 12 shows annual bird mortality from towers with various numbers of guy wire sets from peer-
reviewed studies included in Longcore et al. (2012 in press). Bird mortality is higher at towers with
multiple guy wire sets. The number of guy wire sets typically increases with tower height. As a result the
two factors (tower height and number of guy wire sets) are difficult to separate from one another.
Reducing the number of guy wire sets would reduce avian mortality; however, it is likely that in many
cases the number of guy wire sets could not be safely reduced, since the number of sets is dependent upon
tower height. As noted above, tower owners typically build towers to the minimum height needed so that
construction costs are minimized. In addition, tower height is determined primarily by service needs and
landscape features. While reducing a tower’s height may decrease the number of guy wire sets needed,
building a shorter tower may result in the need for additional towers, which may offset the potential
beneficial impact to birds.
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Environmental Consequences

Figure 12: Bird Mortality and Guy Wire Sets

Tower Lighting Schemes


Lighting appears to be a particularly important variable in avian mortality due to communications towers,
because artificial lights are known to attract night-migrating songbirds, especially on nights of low
visibility due to heavy fog, low cloud ceiling, or precipitation linked to moving or stalled cold fronts
(Tordoff and Mengel 1956, Ball et al. 1995).
Migratory birds’ attraction to lights was first documented in 1874 in Field and Stream magazine and later
by Allen (1880, cited in Cochran 1959), who reported birds being killed from flying into lighthouses.
Cochran and Graber (1958) and Cochran (1959) reported that songbirds were particularly attracted to red
lights at a television tower during poor weather conditions. The presence of fog and mist exacerbate the
situation in two ways. First, moisture causes light to refract off water droplets, resulting in a bright halo
around each tower light and making the tower more attractive to migrating birds. Second, the moon and
stars are obscured, causing birds to abandon their migration flight and instead fly in circles around lit
towers. The circling behavior is thought to result from birds attempting to keep the artificial light source
at a constant bearing as they apparently do with the stars and moon (Emlen 1967, Evans and Ogden 1996,
Åkesson and Bäckman 1999, Mouritsen and Larsen 2001). Once birds lose the light from the stars and
moon they will orient toward any available artificial light (such as tower lighting) and in doing so will
begin circling around the light source, thereby increasing the likelihood of colliding with the tower
structure, guy wires, and other birds (Seeman 2000).
In the first controlled studies where tower lights were intentionally extinguished on foggy nights, birds
were observed to avoid previously lit towers and continue on their migration paths. When the lights were
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Environmental Consequences
turned back on, birds were observed to immediately begin circling around the same towers in large
numbers (Cochran and Graber 1958, Avery et al. 1976). Gauthreaux and Belser (2000) observed that, in
these fog conditions, a greater number of birds were attracted to red strobe lights than to white strobe
lights, and that both red and white strobe lights attracted more birds than did unlit control towers, which
attracted no birds. When weather conditions and visibility improved, in all cases reported in the literature
the birds left the lighted towers, apparently continuing on their migration paths (Gauthreaux and Belser
2000).
Many of the general results of these earlier studies of bird behavior around aviation obstruction marking
lights have been corroborated, but others have been called into question, by Evans et al. (2007).
According to Evans et al. (2007), there was no direct evidence for bird attraction because a light was red –
in spite of the fact that red light had been previously blamed for bird mortality at tall TV towers. Rather,
Evans et al. found that for birds migrating within clouds, steady-burning blue, green, or white lights were
more attractive to birds than red lights. They also reported that any flashing lighting scheme, regardless of
color, would cause less bird aggregation than continuous lighting. Evans et al. also provided strong
circumstantial evidence that flashing white light does not attract birds, and this result corresponds with
evidence these researchers also cite that no large kills have yet been documented at tall broadcast towers
with white strobe lighting.
Gehring et al. (2009) and Longcore et al. (2008) report that lighting types and schemes may be the most
important factors contributing to bird kills at towers. In a study conducted in Michigan, Gehring et al.
(2009) collected avian fatality data simultaneously at 24 towers on consecutive days during peak songbird
migration in spring and fall. They report that towers lit at night with only flashing lights (regardless of
whether they were red or white) were involved in significantly fewer avian fatalities than towers with
current FAA-recommended lighting styles that combine red flashing and red steady-burning lights. Their
results suggest that avian fatalities could be reduced by 50 to 70 percent at guyed communications towers
by removing red steady-burning lights.
Removing red steady-burning lights would likely reduce avian mortality more than changing tower
location or reducing tower heights or the number of guy wire sets. However, under the current FAA
lighting circular, red steady lights are still required at towers that rely on red lighting. Unless the FAA
revises the current lighting circular, tower owners would be prohibited from using only red flashing lights
or turning off red steady-burning lights. Although the FAA lighting styles permit use of white flashing or
strobe lights without steady lighting, white lights typically are not preferred by neighboring residents, and
their use is often restricted by local law.

Species-specific Effects


As described in Section 4.6.3.10, Longcore et al. (2011 in preparation) have proposed that mortality at
communications towers is not equal across all avian taxa. Observed mortality is highest for neotropical
migrants, and for some of these species mortality has been estimated to be more than 1 percent of the
species’ population, which the authors term “biologically significant.” The birds that appear to be most
vulnerable to communications towers include thrushes, vireos, and warblers, which migrate at night and
are therefore susceptible to collisions with towers, especially on foggy nights or on nights with low cloud
ceilings during spring and fall migrations (Manville 2001). Longcore et al. (2011 in preparation) estimate
that 95 percent of tower mortality consists of passerines (songbirds), and that among passerines, mortality
rates are highest for warblers, vireos, sparrows, and thrushes. The authors suggest that mortality may be
more than 1 percent of the species population for 12 species (range 1-8 percent), eight of which are
warblers. One of the 12 is endangered, and eight are Birds of Conservation Concern.
Arnold and Zink (2011) have reported that there are no discernible effects on population trends of North
American birds due to collisions with human-made structures. These researchers found that long distance
or night migrants were more likely to be killed by collisions than year-round resident species or diurnal
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Environmental Consequences
migrants. However, they found no correlation between the number of individuals within a species killed
by collisions and long-term population trends for the same species.
The Bureau does not consider the findings of either Longcore et al. (2011 in preparation) or Arnold and
Zink (2011) to be dispositive. As noted above in Section 4.6.3.1, the Longcore et al. (2011 in
preparation) results were based on a meta-analysis of existing studies that were not designed to address
species-specific effects and in many instances describe extreme episodic events. In addition, the analysis
mixes data from widely divergent time periods during which species populations may vary by as much as
an order of magnitude (Rich et al. 2004). Also, the sample sizes for some of the species for which the
study found greater than 1 percent mortality were very small, which casts into question the reliability of
these findings. Arnold and Zink (2011) have been criticized for their failure to account for regional
variations, their combination of studies in a manner that gives excessive weight to larger data sets, and
their incorporation of insignificant trends and known errors into their regression analysis.
While the Bureau acknowledges that information on species-specific effects would be relevant to the
analysis presented in this PEA, it would be infeasible and unreasonably costly for the FCC to generate
data on species-specific effects from communications towers nationwide on each of the 1,007 migratory
species, or even on the 147 nationally identified BCC species, due to the number of towers that would
need to be studied to account for the various migratory routes of these species. CEQ does not require that
an agency obtain information that is essentially unattainable due to exorbitant costs or the lack of the
means to obtain the information (40 CFR 1502.22[a]).
To the extent evidence exists regarding the effects of individual towers on particular avian species, that
evidence will be considered in the EAs for those applications that require EAs, if the FCC adopts any
option under Alternative 2. Such evidence may also be raised in the FCC’s notice process. If a tower
may significantly affect a threatened or endangered avian species, that effect will be considered as
discussed in Section 5.4.3.2. A species’ status as a Bird of Conservation Concern is relevant to the
determination of whether an effect on that species is significant, but Birds of Conservation Concern are
not afforded special protection under the law.

Declining Mortality Hypothesis


The declining mortality hypothesis is described in detail in Section 4.6.3.10. Over the last five decades of
monitoring bird populations, the number of bird mortalities at towers is reported to be decreasing while
the number of towers is increasing. Morris et al. (2003) reported a significant decrease in the number of
birds salvaged at four towers in New York and Ohio over the 30-year period from 1970-1999. They also
note that other long-term studies consistently show a similar decline in total bird mortality (with other
factors remaining equal, e.g., tower height).
While there is some compelling data suggesting an overall reduction in bird mortality at towers over the
last five decades, this trend is best viewed as being hypothetical because it has been observed at only a
few towers. Therefore, additional research on the declining mortality hypothesis is needed.

Indirect Effects

Indirect effects to migratory birds from individual or groups of towers may include habitat and site
abandonment, habitat loss and fragmentation, attraction to modified habitats, reduced breeding/nesting
density, loss of population vigor and overall density, effects on predator/prey relationships, effects on
behavior including stress, and possibly RF radiation. Of these, habitat and site abandonment have been
the subject of the most research; there is only limited European research available on RF radiation effects
on birds. This PEA addresses the indirect effects of habitat and site abandonment and what little is known
about effects on birds from RF radiation.
Habitat and site abandonment around towers and other vertical structures has been found to be occurring,
specifically with western prairie grouse species which include Lesser and Greater Prairie-Chickens, Sage
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Environmental Consequences
Grouse, and Sharp-tailed Grouse. Two recent studies cited regularly regarding human disturbance and its
effects on Lesser Prairie-Chickens are Robel et al. 2004 and Pitman et al. 2005. These studies showed that
Lesser Prairie-Chickens generally avoid vertical structures, with non-breeding birds generally keeping at
least 0.37 mile (0.60 kilometer) from buildings and transmission lines and towers. Most nests were found
to be placed at least 0.78 mile (1.26 kilometers) from buildings, 0.49 mile (0.79 kilometer) from improved
roads, and 0.22 mile (0.35 kilometer) from transmission lines. However, Pitman et al. 2005 also found
that distance to various disturbance types was a poor predictor of nest success, which is apparently more
dependent on various vegetative characteristics.
The precise mechanism controlling grouse and prairie-chicken abandonment of otherwise suitable habitat
in the presence of tall towers is currently unknown. Similarly, it is unknown whether, in time, local bird
populations may become acclimated to elevated structures and return to the area. However, it has been
speculated that the presence of towers increases predator perching or that predators may increase in areas
that host tall towers. The USFWS has argued that, because prairie grouse evolved in habitats with few
vertical structures for predators to perch upon, placement of tall man-made structures (such as wind
turbines and communications towers) in prairie grouse habitat may result in habitat degradation (Manville
2004). Several studies have shown that prairie grouse avoid other anthropogenic features, such as roads,
power lines, oil and gas wells, and buildings (Robel et al. 2004, Holloran 2005, Pruett et al. 2009). For
example, Greater Sage-Grouse populations have declined in the vicinity of oil and gas development
projects, although declines may not occur until four years post construction (Naugle et al. 2009).
Similarly, Harju et al. (2010) suggested that there is a 2- to 10-year delay before measurable effects on
grouse breeding manifest themselves.
A lek is a traditional site commonly used year-after-year by males of certain species of birds (e.g., greater
and lesser prairie-chickens, sage and sharp-tailed grouse), within which the males display communally to
attract and compete for female mates, and where breeding occurs. In the wind industry, the results of
Robel et al. 2004, Pitman et al. 2005, and other studies have led several state agencies to recommend that
wind turbine towers be sited at least 1 mile (1.6 kilometers) from Lesser Prairie-Chicken lek sites.
Similarly, the USFWS currently recommends that wind turbine towers be placed at least 5 miles (8
kilometers) from grouse lek sites (Manville 2004). USFWS also recommends that a minimum 2-mile
(3.2-kilometer) radius of sagebrush be protected around known leks for non-migratory populations;
protection buffers may have to increase for migratory populations (Braun et al. 1977, Connelly et al.
2000).
Some researchers have suggested that indirect effects on migratory birds also may include possible effects
from RF radiation. At relatively low levels of exposure to RF radiation, the evidence for harmful
biological effects on wildlife is unproven and there is little data available from which to draw any
conclusions. However, the USFWS has expressed concerns that non-ionizing RF radiation, even at levels
too low to cause thermal effects, could be harmful to migratory birds.
Although there have been no published studies on wild breeding birds in North America, some research in
Europe has studied bioeffects from RF other than heating on wildlife. This research has been focused in
two areas: direct impacts from magnetic fields on avian reproduction; and interruptions to avian
navigation since birds are known to navigate using the geomagnetic field.
The presence of electromagnetic fields in the microwave range is considered by some to be a risk factor in
the decline of urban bird populations, especially Balmori (2005, 2009), Balmori and Hallberg (2007), and
DiCarlo et al. (2002). Specifically, research on wild birds at cellular phone tower sites in Valladolid,
Spain, indicated strong negative correlations between levels of tower-emitted microwave radiation and
bird breeding, nesting, and roosting in the vicinity of the electromagnetic fields (Balmori 2005). House
Sparrows, White Storks, Rock Doves, Magpies, Collared Doves, and other species that had historically
been documented to roost and nest in these areas subsequently exhibited nest and site abandonment,
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Environmental Consequences
plumage deterioration, locomotion problems, and even death among some birds found close to cellular
phone antennas. These symptoms were not observed prior to construction of the cellular phone towers.
Balmori and Hallberg (2007) reported that declines of urban House Sparrows in Valladolid, Spain,
increased as electromagnetic field strength increased. Similarly, Everaert and Bauwens (2007) found
strong negative correlations between the amount of radiation present (both in the 900 and 1800 MHz
frequency bands) and the presence of male House Sparrows. Although the existing evidence of
correlation is insufficient to establish causation, Everaert and Bauwens (2007) concluded that long-term
exposure to higher radiation levels may be affecting bird abundance or bird behavior in this species.
Magnetite, a mineral that is highly sensitive to the electromagnetic frequencies that birds use for
navigation, has been discovered in the brains of birds. It has been suggested that RF radiation may act as
an attractant to birds (thereby affecting their navigation) since their eye, beak, and brain tissues contain
high concentrations of magnetite (Ritz et al. 2004).
In laboratory studies, radiation at the same frequency and intensity as that used in cellular telephones in
the United States has appeared to result in the deaths of domestic chicken embryos (DiCarlo et al. 2002,
Manville 2007). These laboratory studies have been interpreted to suggest that non-ionizing RF radiation
at levels far below the existing exposure guidelines for humans may have harmful effects on wild birds.
However, the evidence is insufficient to support a finding that there may be adverse impacts on migratory
bird populations due to RF radiation emissions.

Impacts by Alternative

As discussed below, under the No Action Alternative, Alternative 1, and all options of Alternative 2, the
ASR Program would have short- to long-term major and adverse direct effects on migratory birds due to
collisions with towers, as well as minor indirect effects due to habitat and site abandonment. Chapter 7
explains that when considered in context, these impacts are not significant at the national level, although
depending on the alternative chosen, there may be significant impacts to local populations of migratory
birds or individual Bald and Golden Eagles at proposed tower sites.

No Action Alternative – Direct Effects


Under the No Action Alternative, the current ASR Program and NEPA procedures would continue. Major
adverse impacts on migratory birds due to construction in areas of heavy migration use (coastal zones,
ridgelines, bird staging areas/colonial nesting sites, WHSRN sites, and riparian zones) would continue. As
shown on Figure 13, annual bird mortality from collisions with towers would be expected to increase in
proportion to the number of towers being built, from an estimated 6.6 million birds currently to
approximately 8.6 million birds in the year 2022, based on an estimated 2,800 new towers built annually.
The death of millions of birds annually constitutes a substantial change to the resource. Therefore, the No
Action Alternative would continue to cause short- to long-term major adverse direct impacts to migratory
birds.
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Figure 13: Projected Future Bird Mortality

No Action Alternative – Indirect Effects


Indirect effects (habitat and site abandonment) on migratory birds under the No Action Alternative would
not change from existing conditions. Depending on features of the tower and characteristics of the tower
location, some migratory bird habitat and site abandonment are expected. Most of the research on habitat
and site abandonment due to tall towers has been conducted on grouse and prairie-chicken species in the
western United States (not all of which are migratory). These birds build their nests on the ground and are
known to abandon or avoid otherwise suitable habitats because of the presence of tall man-made
structures (such as wind turbines and communications towers), which increases the number of perching
spots for birds of prey. The No Action Alternative is anticipated to cause short- to long-term minor habitat
and site abandonment impacts to migratory birds because it is not considered likely that all migratory
species would react as grouse and prairie-chickens do by abandoning or avoiding habitat. As
recommended in the mitigation measures discussed in Section 8.4, applicants are encouraged, where
feasible, to protect a minimum 2-mile (3.2-kilometer) radius of sagebrush around known grouse and
prairie-chicken leks.
Based on the limited scientific evidence available, no RF radiation impacts on migratory birds are
anticipated under the No Action Alternative.

Alternative 1 – Direct Effects


Alternative 1 assumes the FAA lighting circular would be revised. Alternative 1 would cause short- to
long-term major adverse impacts to migratory birds, although less than under the No Action Alternative.
Major adverse impacts on migratory birds due to construction in areas of heavy migration use (coastal
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Environmental Consequences
zones, ridgelines, bird staging areas/colonial nesting sites, WHSRN sites, and riparian zones) would
continue. Bird mortality from collisions with towers would be expected to increase in proportion to the
number of towers being built, but the increase would be reduced by an estimated 50 to 70 percent due to
revisions to the FAA lighting circular under which no future registered towers would use red steady-
burning lights.
Under Alternative 1, bird mortality from new towers would decrease by 50 to 70 percent as a result of
revisions to the FAA lighting circular when compared to the No Action Alternative. Thus, total bird
mortality from communications towers, as compared to the No Action Alternative, would decrease from
approximately 8.6 million in the year 2022 to approximately 7.2 million to 7.6 million, assuming 2,800
new towers are built annually. Furthermore, if the FAA permits them to do so, owners of existing towers
with red steady-burning lights would have an incentive to change to lighting styles without red steady-
burning lights, both to reduce their costs for electricity and replacing lighting equipment and to reduce the
effects of their towers on migratory birds. Assuming that the owners of 50 percent of existing registered
towers with red steady-burning lights extinguish those lights or change them to red flashing lights (and
that these towers are evenly distributed across tower heights), this would reduce bird mortality from
existing towers by an estimated 25 to 35 percent. Under this scenario, annual bird mortality from existing
towers would be expected to decrease from 6.6 million currently to between 4.3 million and 5.0 million
birds in the year 2022, and total mortality from existing and new towers in 2022 would be estimated at
between 4.9 and 5.9 million birds.

Alternative 1 – Indirect Effects


Indirect effects (habitat and site abandonment) on migratory birds under Alternative 1 would be similar to
the No Action Alternative. Based on the limited scientific evidence available, no RF radiation impacts on
migratory birds are anticipated under Alternative 1.

Alternative 2 Option A – Direct Effects


Alternative 2 Option A would require an EA for all new towers outside of an antenna farm submitted for
registration – regardless of location, height, use of guy wires, or lighting scheme – and for tower
replacements or modifications that involve a substantial increase in size. The only ASR applications that
would be categorically excluded from preparation of an EA under this option would be those that
propose: (1) a change from red steady-burning to flashing lights or removal of lighting on an existing
tower; (2) a replacement or modification of an existing tower that does not involve a substantial increase
in size; (3) construction in an antenna farm that does not involve a substantial increase in size over
existing towers; or (4) a minor action. Applicants would have an incentive to make changes to existing
towers, where feasible, rather than construct new towers. Further, applicants would be required to
consider, and to mitigate where appropriate, the effects that proposed towers have on migratory birds.
Without changes to the FAA lighting circular, Alternative 2 Option A would cause short- to long-term
major adverse impacts to migratory birds; however, Option A would result in somewhat less bird
mortality than what would be expected under the No Action Alternative. By requiring EAs for all new
construction, Option A would afford an opportunity to identify ways to avoid or mitigate impacts on
migratory birds through the regulatory review of the EA. Also, applicants would have incentive to make
changes to existing towers rather than construct new towers. However, in many instances the factors
contributing to migratory bird deaths would likely be difficult to avoid.
If the FAA revises its lighting circular, Alternative 2 Option A would cause short- to long-term major
adverse impacts to migratory birds, but would result in slightly less bird mortality than Alternative 1.
Because no new towers would have red steady lights in any event, Option A would not reduce the number
of migratory bird deaths due to lighting. By requiring EAs for all new construction, Option A would
afford an opportunity to identify ways to avoid or mitigate impacts on migratory birds due to features
other than lighting through the regulatory review of the EA. However, none of these features appear to be
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as important a contributor to migratory bird mortality as red steady-burning lights. Moreover, factors
contributing to migratory bird deaths other than lighting typically will be difficult to avoid.

Alternative 2 Option A – Indirect Effects


With or without revisions to the FAA lighting circular, indirect effects (habitat and site abandonment) on
migratory birds under Alternative 2 Option A would be somewhat less than those described under the No
Action Alternative, because EAs requiring case-by-case review would be required for all new tower
construction. Based on the limited scientific evidence available, no RF radiation impacts on migratory
birds are anticipated under Option A.

Alternative 2 Option B – Direct Effects


Under Alternative 2 Option B, a proposed new tower would require preparation of an EA only under
certain combinations of location and structural and lighting features. Any proposed new registered tower
that requires an EA under the existing rules would require an EA. Also, if a new tower would be
constructed in an important eagle use area, as determined in consultation with USFWS unless the
applicant’s qualified biologist determines that no Bald or Golden Eagles are or may be present in the
vicinity, the applicant would have to coordinate with USFWS in preparing a site-specific EA. Other
locational features for which a project may require an EA would include ridgelines, coastal zones, and
bird staging areas or colonial nesting sites. If any of those locational features are present, and a tower
would be more than 450 feet (137 meters) tall, would use a red steady-burning lighting scheme, or would
use guy wires, an EA would be required. Towers that are not proposed within any of these locations or
that do not have any of these structural or lighting features would continue to be categorically excluded,
unless they would require an EA under the existing rules or would be located in an important eagle use
area.
Without changes to the FAA lighting circular, Option B would cause short- to long-term major adverse
impacts to migratory birds. By establishing clear guidelines and aligning tower owners’ economic
incentives with the protection of migratory birds, Option B would reduce annual bird mortality compared
to the No Action Alternative to an extent at least comparable to Option A. Option B provides an incentive
to applicants to avoid siting projects that are over 450 feet (137 meters) tall, use red steady lighting, or use
guy wires on ridgelines or in coastal zones, bird staging areas, colonial nesting sites, WHSRN sites, and
riparian zones within wetlands and floodplains. Thus, within the locations that are most sensitive to
migratory birds, Option B provides applicants an incentive to reduce the heights of the tallest towers and
avoid the use of guy wires where feasible, which would reduce avian mortality. Given the substantially
higher number of bird deaths at towers above 950 feet (290 meters) tall, the lack of studies at towers
between 550 and 950 feet (168 and 290 meters), and the mixed findings of the limited evidence for towers
between 400 and 550 feet (122 and 168 meters), it appears that 450 feet (137 meters) is a reasonable
threshold for reducing impacts on migratory birds. Nonetheless, applicants’ ability to avoid tall towers
and the use of guy wires is likely very limited. In many instances, especially at taller towers, it is
economically infeasible to avoid guy wires without compromising structural safety. In addition,
particularly for broadcast towers, it is unlikely in most instances that a tower over 450 feet (137 meters)
tall could be reduced appreciably in height and still be able to meet coverage requirements.
To the extent applicants cannot avoid building towers that are more than 450 feet (137 meters) tall, use
red steady lighting, or use guy wires, Option B provides an incentive to locate these towers away from
ridgelines, coastal zones, bird staging areas, colonial nesting sites, WHSRN sites, and riparian zones
within wetlands and floodplains, thereby reducing the number of migratory birds likely to be affected by
these towers. However, the degree of mortality reduction from re-siting proposed towers would be
limited by applicants’ ability to avoid these locations, as well as by protection already provided under
FCC rules for areas that overlap (e.g., floodplains and wetlands). For example, it is likely that many
towers proposed in coastal zones could not be moved out of the coastal zone, since these areas are
typically large. Colonial nesting sites are typically located in remote areas, so few towers are placed in
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Environmental Consequences
colonial nesting sites and it is unlikely that this would change under Option B. Also, moving a tower off a
ridgeline may result in the need for a taller tower or multiple towers, which may offset the potential
beneficial impacts to birds.
If the FAA does not revise its lighting styles that currently include red steady-burning lights, under
Option B tower owners would be able to avoid the use of red steady-burning lights only by using white
strobe lights. It is anticipated that requiring an EA for towers using red steady-burning lights on
ridgelines or in coastal zones, bird staging areas, colonial nesting sites and WHSRN sites, as well as
requiring a detailed analysis of effects on migratory birds for such towers in riparian zones within
wetlands and floodplains, would lead some tower owners to choose this option. However, given that the
use of white strobe lights raises other environmental concerns, and is often prohibited by local land use
regulations, many projects would still use red steady-burning lights.
If the FAA revises its lighting styles, the requirement to prepare an EA for certain towers using red
steady-burning lights would no longer be applicable because future towers would not use red steady-
burning lights. Under this circumstance, Option B would cause short- to long-term major adverse impacts
to migratory birds, but by establishing clear guidelines and aligning tower owners’ economic incentives
with the protection of migratory birds, it would result in less bird mortality than Alternative 1 and at least
a comparable reduction in bird mortality to what would be expected under Alternative 2 Option A.

Alternative 2 Option B – Indirect Effects


With or without revisions to the FAA lighting circular, indirect effects (habitat and site abandonment) on
migratory birds under Alternative 2 Option B would be slightly less than under the No Action Alternative
due to the preparation and review of EAs for towers meeting certain criteria. However, the reduction
would be less than under Option A, which would require case-by-case review of EAs for all new towers.
Based on the limited scientific evidence available, no RF radiation impacts on migratory birds are
anticipated under Option B.

Alternative 2 Option C – Direct Effects


Under Option C, an EA would be required for any proposed new tower, or replacement or modification of
an existing tower that involves a substantial increase in size, that is more than 450 feet (137 meters) AGL,
regardless of location, lighting scheme, or use of guy wires. Towers less than or equal to 450 feet (137
meters) would be categorically excluded from preparation of an EA, provided that they do not meet any
of the criteria that currently require an EA.
Without changes to the FAA lighting circular, Option C would cause short- to long-term major adverse
impacts to migratory birds. Major adverse impacts on migratory birds due to construction in areas of
heavy migration use (coastal zones, ridgelines, bird staging areas/colonial nesting sites, WHSRN sites,
and riparian zones) would continue. Under Option C, bird mortality would decrease when compared with
the No Action Alternative, but not as much as under Alternative 2 Option A, which requires more EAs, or
Option B, which provides incentives to place new towers that are over 450 feet (137 meters) tall, use red
steady lighting, or use guy wires away from areas important to migratory birds, as well as to reduce the
heights of the tallest towers and avoid use of red steady-burning lights and guy wires within these areas
where feasible. Applicants may try to reduce tower heights if possible to avoid preparing an EA and
thereby reduce their application costs and agency approval times. However, particularly for broadcast
towers, it is typically unlikely that a tower over 450 feet (137 meters) tall could be reduced appreciably in
height and still be able to meet coverage requirements. While in some cases it may be possible to reduce
towers that would otherwise have been slightly over 450 feet (137 meters) to a level just below that
threshold, such a limited reduction in height is unlikely to have much impact on avian mortality. Option
C would also have some beneficial effect on avian mortality by requiring consideration of the effects that
proposed towers over 450 feet (137 meters) would have on migratory birds through the EA process.
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Environmental Consequences
If the FAA revises its lighting circular, Alternative 2 Option C would cause short- to long-term major
adverse impacts to migratory birds. Major adverse impacts on migratory birds due to construction in
areas of heavy migration use (coastal zones, ridgelines, bird staging areas/colonial nesting sites, WHSRN
sites, and riparian zones) would continue. Option C would result in less bird mortality than Alternative 1,
but the decrease would be less than under Option A because fewer EAs would be prepared, or under
Option B which provides incentives to place towers that are over 450 feet (137 meters) tall or use guy
wires away from resources important to migratory birds, and to reduce tower heights and avoid guy wires
within these areas if feasible. However, opportunities for significant reductions in height are very limited.

Alternative 2 Option C – Indirect Effects


With or without revisions to the FAA lighting circular, indirect effects (habitat and site abandonment) on
migratory birds under Alternative 2 Option C would be slightly reduced compared to the No Action
Alternative, due to the case-by-case review of EAs required for towers over 450 feet (137 meters) tall, but
the reduction would be less than under Option A or Option B. Based on the limited scientific evidence
available, no RF radiation impacts on migratory birds are anticipated under Option C.
5.4.3.4 Bald and Golden Eagles
Breeding, feeding, and sheltering activities of Bald and Golden Eagles can be disturbed by construction of
new tower facilities within their ranges, while Bald Eagles nesting on or near existing communications
towers can be disturbed by tower maintenance activities. These disturbances could agitate or bother a
Bald or Golden Eagle to a degree that causes, or is likely to cause, (1) injury to an eagle, (2) a decrease in
its productivity, by substantially interfering with normal breeding, feeding, or sheltering behavior, or (3)
nest abandonment.
Under the Bald and Golden Eagle Protection Act, significance of environmental effects is related to
population impacts. The BGEPA prohibits anyone without a permit from “taking” Bald and Golden
Eagles, including their parts, nests (active and inactive) or eggs, by pursuit, shooting, shooting at,
poisoning, wounding, killing, capturing, trapping, collecting, molesting or disturbing. The definition of
“disturb” under BGEPA includes: “to agitate or bother a Bald or Golden Eagle to a degree that causes, or
is likely to cause, based on the best scientific information available, (1) injury to an eagle, (2) a decrease
in its productivity, by substantially interfering with normal breeding, feeding, or sheltering behavior, or
(3) nest abandonment, by substantially interfering with normal breeding, feeding, or sheltering behavior.”
In late 2009, the USFWS proposed two new regulations to authorize limited take of eagles by means of
“disturbance,” “take resulting in mortality,” and take of eagle nests for health and safety reasons. Under
these regulations, where an activity will “take” Bald Eagles – either through “disturbance” or by lethal
means – an individual “take” permit under BGEPA is required to be in compliance with the law. For
Golden Eagles, USFWS will likely only consider programmatic “take” permits (authorized under 50 CFR
22.3 for “take that is recurring, is not caused solely by indirect effects, and that occurs over the long term
or in a location or locations that cannot be specifically identified”). Guidance for implementing
individual and programmatic take permits is presently being developed.
For both species, permits will only be issued where the breeding population of the raptor is stable or
increasing. Because construction of communications towers may result in the take of Bald and Golden
Eagles under BGEPA, USFWS suggests that tower owners and/or operators contact the nearest USFWS
Ecological Service’s Field Office for guidance on eagle issues and permitting. If eagle habitat is present
and the project area could contain a nest, USFWS would advise the tower owner to arrange for a qualified
biologist to conduct a nest clearance survey for Bald and Golden Eagles if construction would occur
within the nesting season. If active nests are identified, USFWS would advise the tower owner to
coordinate with USFWS to develop appropriate measures to reduce impacts to nesting eagles by
implementing spatial buffers and/or temporal restrictions on construction activities.
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Environmental Consequences

No Action Alternative


Because the current ASR Program does not require an EA for projects located near Bald or Golden Eagle
nests, projects located near these nests would continue to be categorically excluded under the No Action
Alternative if no other criteria requiring an EA are present. Construction activities near active nests would
continue to cause adverse impacts on Bald and Golden Eagles due to disturbance of breeding, nesting,
feeding, and sheltering activities. Newly constructed towers may also provide new nest sites for Bald
Eagles, which may then be disturbed by subsequent tower maintenance activities. Although these
disturbances would be limited to the period of construction or maintenance, they may have a readily
apparent impact on individual Bald and Golden Eagles. Therefore, the No Action Alternative would
continue to cause short-term minor to moderate adverse impacts on Bald and Golden Eagles.

Alternative 1


Alternative 1 would be expected to have similar impacts on Bald and Golden Eagles as described under
the No Action Alternative.

Alternative 2 Option A


Alternative 2 Option A requires an EA for all new towers outside of an antenna farm and for certain
changes to existing towers, regardless of location. Under Option A, applicants would need to take into
account effects on Bald and Golden Eagles, and to consult with USFWS when Bald and Golden Eagles
would be affected, when preparing the EA. USFWS would be expected to note the presence of nearby
Bald and Golden Eagle nests, and to recommend appropriate actions to reduce impacts. Therefore, under
Option A, short-term minor adverse impacts to Bald and Golden Eagles are anticipated,

Alternative 2 Option B


Option B of Alternative 2 requires that an EA be prepared in coordination with the USFWS for projects
that would be constructed in an important eagle use area. Determination of whether a project site is in an
important eagle use area would be made in consultation with USFWS, unless the applicant’s qualified
biologist determines that no Bald or Golden Eagles are or may be present in the vicinity. While it is
probable that USFWS will not require coordination if the proposed tower would be more than 660 feet
(201 meters) from a Bald Eagle nest or 0.6 mile (1 kilometer) from a Golden Eagle nest, USFWS may
determine that certain towers outside these radii should require an EA. Applicants would have an
incentive under Option B to locate towers away from eagle nests where feasible. Furthermore, towers
located near eagle nests would be reviewed by USFWS, which would be expected to note the presence of
nearby Bald and Golden Eagle nests, and to recommend appropriate actions to reduce impacts.
Therefore, under Option B, short-term minor adverse impacts to eagles are anticipated. It is anticipated
that the reduction in impacts on Bald and Golden Eagles under Option B, compared to the No Action
Alternative, Alternative 1, or Alternative 2 Option C, would be at least comparable to Option A.

Alternative 2 Option C


Under Alternative 2 Option C, an EA that considers effects on migratory birds is required for new towers
that are more than 450 feet (137 meters) tall. Therefore, these towers, which may have the greatest
potential impact on Bald and Golden Eagles due to their size, would be reviewed for effects on Bald and
Golden Eagles during the EA process. The EA requirement for towers over 450 feet (137 meters) tall
may cause a limited reduction of tower heights for some towers, which may benefit Bald Eagles by
making them less attractive as nesting sites, depending on other site characteristics. Under Option C there
would be no incentive to move towers away from areas occupied by Bald or Golden Eagle nests.
Therefore, Option C would be expected to cause short-term, minor to moderate adverse impacts to Bald
and Golden Eagles, although to a slightly lesser degree than under the No Action Alternative or
Alternative 1.
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5.4.4 Cultural Resources
Section 106 of the NHPA directs the Federal Government to consider the effects of its undertakings on
historic properties through a four-step decision-making and compliance process. The law does not
mandate preservation of historic properties; rather, it mandates that Federal agencies consider the effect of
their undertakings on historic properties. The four steps of the Section 106 compliance process are:
·
Establish whether a proposed action constitutes an undertaking
·
Identify National Register-listed or eligible properties
·
Assess effects of a proposed action on eligible historic properties
·
Resolve adverse effects to eligible historic properties through consultation with the State/Tribal
Historic Preservation Office (SHPO/THPO) and the Advisory Council on Historic Preservation,
as necessary
In September 2004, the Advisory Council on Historic Preservation, the National Conference of SHPOs,
and the FCC executed a Nationwide Programmatic Agreement for Review of Effects on Historic
Properties for Certain Undertakings Approved by the Federal Communications Commission
(FCC 2004).
This Nationwide Programmatic Agreement streamlines and tailors the Section 106 review process for
undertakings involving the construction and modification of communications facilities. Under the NPA,
almost all towers are subject to Section 106 review, with limited defined exceptions. Most collocations
are exempt from Section 106 review under an earlier Collocation Agreement that was incorporated into
the NPA. The NPA does not apply on Tribal lands.
The Section 106 process must be completed before a project can be determined to be categorically
excluded or a FONSI can be issued. The Section 106 process is considered complete if there is a finding
of No Historic Properties Affected or No Adverse Effect. If there is an adverse effect, the FCC executes a
Memorandum of Agreement (MOA) to complete the process, and then it requires an EA to be prepared.
Provided the agreement document has been executed, the actions outlined in the MOA do not have to be
completed before the EA is finalized.

No Action Alternative


Because most new tower construction involves some level of ground-disturbing activities (e.g.,
construction of the tower, utility infrastructure, and access roads), construction of new towers has the
potential to affect archaeological resources. Any tower projects that would involve renovations to
buildings or structures that are either historic properties or within historic districts have the potential to
affect architectural resources. Both types of projects have the potential to affect Traditional Cultural
Properties and Native American religious and cultural sites. Because they involve structures that in most
instances project 200 feet (61 meters) or more AGL, most ASR Projects also have the potential to impose
visual adverse effects on resources of any type for which visual setting or visual elements are character-
defining features of eligibility.
Under the NPA, once Areas of Potential Effect (for direct and visual effects) have been established for a
particular undertaking, the applicant is directed to take specific steps to identify historic properties and
assess effects on those properties. These steps include reviewing publicly available sources identified by
the SHPO/THPO, gathering information from Indian Tribes and Native Hawaiian organizations, and
inviting public and local government participation. Fieldwork will usually be required to identify
archaeological resources and may be required for other resources. Upon completion of the applicant’s
identification and assessment efforts, its work will be reviewed by the SHPO/THPO. The FCC is
committed to engage in government-to-government consultation with federally recognized Indian Tribes
that have an interest in a proposed construction unless the Tribe has agreed that consultation is
unnecessary.
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Environmental Consequences
In general, ASR Program actions have the potential to affect historic properties if they may visually affect
buildings, sites, structures, landscapes, districts, and objects eligible for or listed in the NRHP. Actions
also have the potential to affect archaeological resources if they involve excavation, grading, or other
modifications to land. While unusual, it is also possible for an ASR Program action to affect historic
properties if it involves structural modification, maintenance, rehabilitation and renovation, or the sale or
lease of a historic property. The FCC is responsible to ensure that its licensees and those constructing for
a licensee properly undertake the Section 106 review process to identify historic properties, determine the
effects of undertakings on identified historic properties, and resolve adverse effects of their undertakings
to historic properties. Under current ASR Program rules, an EA must be prepared for tower projects that
cause adverse effects to historic properties. It is the FCC’s practice that applicants should complete the
Section 106 process before preparing an EA to ensure that effects to historic properties have been taken
into account in the NEPA process.
As a result of the process that the FCC requires its applicants to follow under Section 106 of the NHPA,
and in accordance with the NPA, it is expected that the ASR program would have short- to long-term
negligible to minor adverse impacts on cultural resources under the No Action Alternative.

Alternative 1


Under Alternative 1, impacts to archaeological and architectural resources and Native American religious
and cultural sites would be similar to the No Action Alternative

Alternative 2 Options A, B, and C


Under all options of Alternative 2, impacts to archaeological and architectural resources and Native
American religious and cultural sites would be similar to the No Action Alternative.
5.4.5 Other Visual and Aesthetic Resources
New tower sites could be placed within a variety of settings, including recreation areas; parks and
preserves; commercial areas; or urban, suburban, or rural residential areas. The potential for impacts from
construction of new towers is greater for some of these types of settings than others, with the nature and
extent of site-specific impacts being related to the degree to which the structures associated with a
proposed action contrast with the features in the existing landscape. In general, the impacts on visual
resources are likely to be greater in undeveloped rural or natural settings than suburban, urban, or
commercial settings, where towers and antennas are more common. The degree of impact might also be
greater at a specific time of day or year. Tower features are generally more visible during the day, thereby
causing greater impacts; however, tower lighting would contribute to visual impacts at night as well.
Impacts on visual resources would be short-term (due to construction activity) and long-term (due to
presence of a new tower in the landscape).

No Action Alternative


Residential neighborhoods and other local land uses are typically governed by local comprehensive plans
that specify the allowable types and locations of future land use. New towers would continue to be subject
to review by local jurisdictions and a continuation of the existing ASR Program would not affect those
reviews. Tower construction would also remain subject to other Federal, state, and local laws protecting
particular viewsheds. In addition, as discussed in Section 5.4.4, the FCC’s review process under Section
106 of the NHPA would require consideration of visual impacts to historic properties. The FCC’s rules
require preparation of an EA when a tower would use high-intensity white lights in a residentially zoned
neighborhood.
Short-term and long-term, minor to moderate adverse impacts on visual resources would be expected
under the No Action Alternative. There are several potential sources of short-term impacts on visual
resources, including the clearing and grading of land for the tower site footprint, the construction of
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Environmental Consequences
infrastructure necessary to install and operate the tower (access road, utility corridor, and staging areas),
and the construction of the tower and equipment building. Permanent features that might create a long-
term contrast with the existing environment would include the tower, the access road, the fenced
perimeter of the site, the building housing the generator and electronics, and overhead transmission lines
if required for power or communications (as opposed to buried lines).
The short-term impacts on visual resources resulting from construction activities and the long-term
impacts resulting from the placement of potentially contrasting visual features into the existing landscape
would be expected to be adverse and range from minor to moderate, depending on the degree of contrast
that the change represents relative to the existing landscape.
Potential impacts on visual resources could be avoided or minimized through selection of sites, where
possible, that lie in areas with substantial existing visual clutter (such as commercial areas) and that have
existing roads and utility corridors that could be used to service the site. Other methods of mitigation
might include use of vegetation screening or differences in topography to reduce the visual contrast of the
permanent features at the site. In some instances, the locations of new sites could also be consolidated
with other contrasting visual elements (e.g., existing utility towers, water towers, communications towers)
to reduce visual sprawl and disturbance related to lighting, or the features of towers could be designed to
blend more effectively with the forms and lines found in the existing landscape (for example, painting
towers, fences, or concrete foundations with earth-tone paint or stain to reduce contrasts, or using rustic
designs and native materials).

Alternative 1


Impacts to visual resources under Alternative 1 would be similar to those described under the No Action
Alternative

Alternative 2 Options A, B, and C


Impacts to visual resources under all options of Alternative 2 would be similar to those described under
the No Action Alternative.
5.4.6 Economics
The No Action Alternative, Alternative 1, and all options of Alternative 2 include the FCC’s recently
adopted public notice and public comment procedures. Therefore, this PEA does not address the
economic impacts that existed before these procedures were adopted.

No Action Alternative


Under the No Action Alternative, there would be a short- to long-term minor adverse economic impact on
applicants proposing new towers for registration due to the cost of preparing EAs.
Under the No Action Alternative, the existing ASR program would continue and EAs would typically be
required only for new towers that have features for which the FCC currently requires an EA. As a result
of the new public notice process, the proportion of new towers requiring EAs is likely to increase slightly
from recent years, although this could be offset by a decrease in the number of towers constructed.
Although 132 tower registrations required EAs in 2011, this number has more typically ranged from 65 to
75 per year. Moreover, 90 of the 132 EAs filed in 2011 were for towers under 200 feet (61 meters), many
of which did not require registration. The Bureau therefore estimates that the total number of EAs
prepared beginning in 2012 will be 100 per year. The estimated typical cost of EA preparation for a tower
would continue to range from approximately $5,000 to $15,000, depending on the complexity of issues
and resources to be addressed, and the time required to complete an EA would be similar to recent years
because notice and comment would occur simultaneously with other processes. It is anticipated that the
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Environmental Consequences
FCC would continue to review and process most filed EAs within 40 to 50 days and would not require
additional staff.

Alternative 1


Alternative 1 would have a short- to long-term minor adverse economic impact on applicants proposing
new towers for registration, as described under the No Action Alternative. Because Alternative 1 would
not change the situations for which an EA is required, the number and typical cost of EAs is expected to
be the same as under the No Action Alternative.

Alternative 2 Option A


Alternative 2 Option A would have a short- to long-term moderate adverse economic impact on
applicants proposing new towers for registration.
Option A would require an EA for all new towers outside of an antenna farm submitted for registration –
regardless of location, height, use of guy wires, or lighting scheme – and for certain replacement towers
and changes to existing towers. Additional costs to applicants would result from the increased number of
EAs that would be required under Option A. As described in Section 4.2.4, it is conservatively estimated
that 2,800 new registered towers would be constructed each year over the next 10 years; under Option A,
each of these applications would require preparation of an EA. The estimated typical cost of EA
preparation for a tower would continue to range from approximately $5,000 to $15,000 depending on the
complexity of issues and resources to be addressed.
Construction of towers may be delayed by the time necessary for the applicant to prepare an EA for each
tower and for the FCC to process the filed EAs (typically 40 to 50 days), to the extent these tasks cannot
be completed concurrently with other pre-construction activities. The FCC would require substantial
additional staff time to review and process an estimated 2,800 EAs a year. To maintain current processing
timelines, the FCC would need to reallocate staff from existing duties to review and process EAs or
obtain additional funds to hire more staff. If neither of these occurs, there would likely be extensive
delays in EA processing times.

Alternative 2 Option B


Alternative 2 Option B would have a short- to long-term minor adverse economic impact on applicants
proposing new towers for registration, although this impact would be somewhat greater than under the No
Action Alternative or Alternative 1.
Additional costs to applicants would result from the increased number of EAs that would be required
under this option. There may also be costs associated with construction of lattice towers to avoid having
to prepare EAs for guyed towers, but few applicants would likely find it technically feasible or cost-
effective to make this change merely to avoid completing EAs.
Currently, an estimated 60 percent of registered towers use red steady-burning lights (FCC 2012),
including most towers over 200 feet (61 meters). While the FCC does not currently track the number of
towers that employ guy wires, the Bureau estimates that roughly 50 percent do so, including most towers
over 300 feet (91 meters) and virtually all towers over 450 feet (137 meters). Because there is a
substantial overlap among towers that are over 450 feet (137 meters), use red steady-burning lights, and
use guy wires, the Bureau estimates that roughly 70 percent of registered towers have one or more of
these features. This number is reduced to 65 percent for purposes of calculating the number of EAs,
under the assumption that some applicants that otherwise would have used red steady-burning lighting
schemes will choose white strobe lighting (if permitted by local regulations), or in rare instances reduce
the height of towers to below 450 feet (137 meters) or eliminate the use of guy wires, to avoid having to
prepare EAs.
Further, the Bureau assumes that roughly 10 percent of registered towers would be in locations where
Option B requires an EA for towers that are over 450 feet (137 meters) tall, use red steady-burning lights,
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Environmental Consequences
or use guy wires – on a ridgeline, in a coastal zone, or in a bird staging area/colonial nesting site or
WHSRN site. It is assumed that the number of towers constructed within important eagle use areas
would be negligible.
It is conservatively estimated that a total of 2,800 new registered towers would be constructed each year
over the next 10 years. An estimated 100 of these towers would require EAs under the No Action
Alternative, and would also require EAs under Option B. If the FAA advisory circular is not revised, the
Bureau estimates that 65 percent of 10 percent of the towers not requiring an EA under the No Action
Alternative would require an EA under Option B, or an estimated 176 towers. Adding the 100 EAs
required under the No Action Alternative to this estimate means that 276 EAs would be prepared each
year.
If the FAA changes its advisory circular, no EAs would be prepared for towers using red steady lights.
Taking into account only towers that are over 450 feet (137 meters) tall or use guy wires, 50 percent of 10
percent of the towers not requiring an EA under the No Action Alternative would require an EA under
Option B, or 135 towers. Adding the 100 EAs already required under existing conditions means 235 EAs
would be prepared each year.
The estimated typical cost of EA preparation for a tower would continue to range from approximately
$5,000 to $15,000 depending on the complexity of issues and resources to be addressed. Construction of
towers may be delayed by the time necessary for the applicant to prepare an EA and for the FCC to
process the filed EA (typically 40 to 50 days), to the extent these tasks cannot be completed concurrently
with other pre-construction activities. The FCC would require additional staff time to review and process
an estimated 235 to 276 EAs a year. To maintain current processing timelines, the FCC would need to
reallocate staff from existing duties to review and process EAs or obtain additional funds to hire more
staff. If neither of these occurs, there could be delays in EA processing times.

Alternative 2 Option C


Alternative 2 Option C would have a short- to long-term minor adverse economic impact on applicants
proposing new towers for registration. This impact would be greater than under the No Action Alternative
or Alternative 1 but less than under Alternative 2 Option B.
Under Option C, proposed towers less than or equal to 450 feet (137 meters) AGL that have features for
which the FCC currently requires an EA and all towers over 450 feet (137 meters) AGL would require an
EA. Additional costs to applicants would result from the increased number of EAs that would be required
under Option C. As discussed under the No Action Alternative, the Bureau anticipates that 100 EAs
would be prepared per year for towers less than 450 feet (137 meters) tall. Based on the number of
applications for new towers over 450 feet (137 meters) AGL in the past six years, the Bureau estimates
that approximately 65 new tower applications for towers over 450 feet (137 meters) tall would be
submitted to the FCC annually. Altogether, the Bureau assumes that under Option C, an estimated 165
EAs would be prepared every year. The estimated typical cost of EA preparation for a tower would
continue to range from approximately $5,000 to $15,000 depending on the complexity of issues and
resources to be addressed. The Bureau expects no increase in the time for applicants to complete an EA in
the typical case because notice and comment would occur simultaneously with other processes. The FCC
would require additional staff time to review and process approximately 165 EAs per year. This may
result in a minor increase in the time required to process a filed EA (typically 40 to 50 days).
5.4.7 Radio Frequency Radiation
No RF impacts on human populations are expected from the No Action Alternative, Alternative 1, and all
options of Alternative 2. Under all alternatives, the FCC would require an EA when RF exposure from a
tower would exceed either the occupational or general population MPE limits. In practice, licensees and
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Environmental Consequences
tower owners invariably design their facilities so that the MPE limits will not be exceeded. The Bureau
expects that this practice will continue under any alternative.
Potential impacts of RF radiation on migratory birds are discussed in Section 5.4.3.3.
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Cumulative Impacts

SECTION SIX

CUMULATIVE IMPACTS

6.1 INTRODUCTION
CEQ defines cumulative effects as the “impact on the environment, which results from the incremental
impact of the action(s) when added to other past, present, and reasonably foreseeable future actions
regardless of what agency (Federal or non-Federal) or person undertakes such other actions
” (40 CFR
1500). Cumulative impacts can result from individually minor, but collectively substantial, actions
undertaken over a period of time by various agencies (Federal, state, and local) or individuals. In
accordance with NEPA, a discussion of cumulative impacts resulting from projects that are proposed (or
anticipated over the foreseeable future) is required.
To identify cumulative effects, the analysis needs to address two fundamental questions:
1. Does a relationship exist such that affected resource areas of a proposed action or alternatives
might interact with the affected resource areas of past, present, or reasonably foreseeable actions?
2. If such a relationship exists, then are there any potentially significant impacts not identified when
a proposed action is considered alone?
The scope of the cumulative effects analysis involves both the geographic extent of the effects and the
time frame in which the effects could be expected to occur, as well as a description of what resources
could potentially be cumulatively affected.
When applying the concept of cumulative impacts to a programmatic analysis, some additional
consideration must be given to existing uncertainty associated with specific locations that will be selected
in the future. Communications towers could be proposed anywhere within the United States including its
territories. Therefore, this PEA addresses cumulative impacts qualitatively.
In evaluating the cumulative impacts of an action, an agency considers the total effects on a resource,
ecosystem, or human community of that action and all other activities affecting that resource, no matter
what entity (Federal, non-Federal, or private) is taking the actions. Cumulative impacts involve the
combined, incremental effects of human activity. In accordance with NEPA and to the extent reasonable
and practical, this PEA considers the combined effects of the No Action Alternative, Alternative 1, and all
options of Alternative 2 with other past, present, and reasonably foreseeable actions that may affect the
resources identified. For example, other potential impacts on birds include collisions with other vertical
structures, predation by cats, and population changes due to climate change. This PEA also considers
under cumulative impacts the combination of the environmental effects of future towers to be registered
under the ASR program with the ongoing effects of existing registered towers.
The No Action Alternative, Alternative 1, and all options of Alternative 2 will result in negligible, minor,
or moderate adverse impacts to all resources addressed in this PEA, except for migratory birds. Under all
alternatives impacts to migratory birds at the national level would be major and adverse. The Bureau
concludes that the negligible, minor, and moderate impacts of the ASR Program on resources other than
migratory birds, when viewed in the context of all impacts on each resource, are not cumulatively
significant. Therefore, only migratory birds (including any listed as threatened or endangered) are
addressed in detail in terms of potential cumulative impacts. Because of the importance of tower lighting
to impacts to migratory birds, this chapter discusses cumulative impacts with and without the potential
FAA lighting changes. Only direct impacts (bird mortality due to collisions with communications towers)
are addressed in this cumulative analysis. As discussed in Chapter 5, indirect adverse impacts to
migratory birds due to site and habitat abandonment are minor, and the evidence is insufficient to support
a finding that there may be adverse impacts on migratory bird populations due to RF radiation emissions.
It should be noted that lighting on new towers must conform to the requirements of the current FAA
Advisory Circular 70/7460-1K Obstruction Marking and Lighting (USDOT/FAA 2007). The FCC cannot
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Cumulative Impacts
require lighting schemes that are not in compliance with this circular. Currently the FAA does not allow
lighting configurations that use red flashing lights without also requiring the presence of red steady-
burning lights. Following its anticipated publication of the results of a conspicuity study, the FAA may
revise the circular so that new communications towers that use red flashing lights would not also have red
steady-burning lights.
6.2 PAST, PRESENT, AND REASONABLY FORESEEABLE PROJECTS AND

ACTIONS CONSIDERED

Communications towers comprise part of the built environment that causes impacts to birds. The known
and reasonably foreseeable projects, actions, and conditions considered as part of the cumulative impact
analysis include:
·
Existing communications towers
ü Those registered in the ASR Program
ü Those not required to be registered in the ASR Program (including towers used solely by
federal agencies)
·
Reasonably foreseeable future communications tower construction
·
Other existing sources of avian mortality and conditions that affect birds
ü Collisions with buildings, windows, and wind turbines
ü Collisions with power lines
ü Collisions with motor vehicles
ü Predation by cats
ü Global warming/climate change
6.3 GEOGRAPHIC EXTENT AND TIME FRAME
The geographic extent of the cumulative impact analysis includes the area under the jurisdiction of the
ASR program – the United States and its territories. Since the cumulative impact analysis includes other
recent past, present, and reasonably foreseeable future actions, the Bureau has set a timeframe for the
cumulative analysis. This analysis includes past actions from 1995 when the ASR Program was
established and future projects until the year 2022.
6.4 CUMULATIVE IMPACTS TO MIGRATORY BIRDS
There are numerous anthropogenic and natural sources of mortality to migratory birds. The sections
below first review the expected direct impacts on migratory birds from existing towers and new registered
towers under each of the program Alternatives, then describe the direct impacts on migratory birds from
climate change and other activities that cause bird mortality. The final section summarizes the overall
cumulative impacts on migratory birds from all of these actions and sources.
Direct adverse impacts to migratory birds occur when birds collide with the tower structure, supporting
guy wires, or each other. High avian mortality at towers is usually episodic and typically occurs under
inclement weather conditions during the spring and fall migration seasons when steady-burning lights
attract birds to a tower.
The discussion of cumulative impacts in this PEA is framed in terms of effects on all birds or, to the
extent information is available, all migratory birds or neotropical migratory songbirds. The Bureau
acknowledges that cumulative impacts on individual species are also relevant to evaluating whether, for
example, the Proposed Action combined with other known and reasonably foreseeable actions may place
a species population in jeopardy. However, as discussed in Section 4.6.3.1 above, the data associated
6-2

Cumulative Impacts
with effects of communications towers on individual species are subject to considerable uncertainty.
Similarly, there is little available information regarding the impacts on individual bird species from other
sources. Although information on species-specific cumulative effects would be relevant to the analysis
presented in this PEA, it would be infeasible and unreasonably costly for the FCC to generate such data
on each of the 1,007 migratory species, or even on the 147 nationally identified BCC species. CEQ does
not require that an agency obtain information that is essentially unobtainable due to exorbitant costs or the
lack of means to obtain the information (40 CFR 1502.22[a]). Moreover, to the extent that evidence
exists regarding cumulative effects on individual species, under any option of Alternative 2 that evidence
will be considered in the EAs for those applications that require EAs, and such evidence may also be
raised in the FCC’s notice process.
6.4.1 Impacts from Existing Towers
As of February 1, 2012, there were 96,039 communications towers nationwide, including in the five U.S.
territories, identified in the FCC database as having a construction date (FCC 2012). Avian mortality
from collisions with existing communications towers is conservatively estimated at approximately 6.6
million birds annually (Longcore et al. 2012 in press). Data do not exist to distinguish the number of
birds killed at registered towers from those killed at towers that do not require registration. However,
because towers used by FCC licensees that do not require registration are less than 200 feet (61 meters) in
height and there are relatively few towers used solely by Federal agencies, it is reasonable to assume that
substantially all of the 6.6 million bird deaths occur at registered towers.
Migratory songbirds comprise approximately 95 percent of the avian mortality at communications towers.
Total population estimates for migratory birds range from approximately 10 to 20 billion (USFWS
2002b), with songbirds comprising more than 50 percent of the species represented (Blancher et al. 2007).
Conservatively assuming a total migratory bird population of 10 billion birds, communications tower
collisions currently cause no more than 0.07 percent annual mortality to the total migratory bird
population.
Under Alternative 1, if the FAA permits them to do so, owners of existing towers with red steady-burning
lights would have an incentive to change to lighting styles without red steady-burning lights, both to
reduce their costs for electricity and replacing lighting equipment and to reduce the effects of their towers
on migratory birds. Assuming that the owners of 50 percent of registered towers with red steady-burning
lights extinguish those lights or change them to red flashing lights (and that these towers are evenly
distributed across tower heights), this would reduce bird mortality from existing towers by an estimated
25 to 35 percent. Therefore, under Alternative 1, future avian mortality from existing towers is estimated
to be between 4.3 million and 5.0 million birds per year. A similar reduction would occur under all
options of Alternative 2 if the FAA revises its lighting circular.
6.4.2 Impacts from New Registered Towers
As described in Section 5.3.2, it is assumed that the number of towers to be constructed over the next 10
years under Alternative 1 and all options of Alternative 2 will be similar to the number of new towers
under the No Action Alternative. Under the existing ASR Program and FAA lighting circular that
currently requires steady-burning lights whenever red flashing lights are used, migratory bird mortality
levels at new towers would be expected to be proportional to mortality from existing towers.
Approximately 2,800 new registered communications towers are conservatively projected to be
constructed annually over the next 10 years. These 28,000 towers represent an approximate 30 percent
increase over the 96,039 communications towers in the existing environment as of February 1, 2012 (FCC
2012). Based on the estimated current annual avian mortality of 6.6 million birds, by the year 2022 the
annual avian mortality from new and existing towers would reach 8.6 million under the No Action
Alternative.
6-3

Cumulative Impacts
Under Alternative 1, it is assumed that the FAA will revise its lighting circular so that new towers with
red flashing lights will not also use red steady lights. This change would result in a 50 to 70 percent
reduction in avian mortality from new towers (Gehring et al. 2009) compared to the No Action
Alternative.
As described in Section 5.4.3.3, even if the FAA does not revise its advisory circular, Alternative 2 (all
options) would also be expected to reduce the amount of avian mortality from new towers when
compared to future conditions under the No Action Alternative, although to a much lesser degree than
Alternative 1. Because some or all proposed tower registrations would go through a more rigorous
environmental review under all options of Alternative 2, it is expected that some tower owners would
consider location or design changes to their proposed towers so that the tower would be categorically
excluded from preparation of an EA (under Options B and C), and that the implementation of mitigation
measures would reduce effects on migratory birds at towers that cannot be categorically excluded so that
a FONSI can be issued (under all options). However, the ability to implement measures that would
reduce the direct effects of towers on migratory birds would likely be limited. If the FAA revises its
advisory circular so that future towers do not use red steady lights, the reduction in avian mortality from
new towers under all options of Alternative 2 would be in addition to the 50 to 70 percent reduction
expected under Alternative 1.
6.4.3 Effects from Climate Change
Climate change works over a longer timeframe than is covered by the analysis in this PEA but its effects
on migratory birds are relevant to a cumulative effects analysis. For example, warmer winters in recent
decades have played an important role in shifting winter bird ranges to the north (NABCI 2010).
Christmas Bird Count data from the mid-1960s through 2006 show that 170 (56 percent) of the 305 most
widespread, regularly occurring species have shifted their ranges to the north, whereas only 71 species
(23 percent) have shifted their ranges to the south and 64 species (21 percent) have not shifted their
ranges significantly north or south.
The North American Bird Conservation Initiative, U.S. Committee (2010) reported that climate change
may interact with and intensify many of the existing stressors on birds. Birds and habitats that are already
adversely affected may be highly vulnerable to additional impacts due to climate change.
6.4.4 Impacts from Other Sources
As discussed in Section 4.6.3.11, in addition to communications towers, there are other anthropogenic
causes of mortality in birds, including collisions with buildings, windows, motor vehicles, and wind
turbines, as well as predation by cats. Erickson et al. (2005) summarized and described the various avian
mortality sources and estimated that 500 million to possibly over 1 billion birds are killed annually.
They assumed that cat predation accounted for approximately 100 million bird deaths a year and that
buildings and windows caused approximately 550 million annual deaths. More recent studies estimate
that free-ranging domestic cats and building glass may each kill at least 1 billion birds annually
(Dauphiné and Cooper 2009, Klem et al. 2009). (There are no estimates of how many of these birds are
migratory; however, most are assumed to be. For example, Klem et al. [2009] reported that of the top ten
species collected during autumn and spring studies of collisions with buildings, ten and nine species,
respectively, were migratory.) Combining these studies, total annual mortality from anthropogenic
sources and cat predation exceeds 2 billion birds per year.
Table 6 in Section 4.6.3.11 summarizes the mortality estimates from several anthropogenic sources as
well as cat predation. Cat predation and avian collisions with buildings and power lines appear to cause
the bulk (> 80 percent) of the annual avian mortality attributable to these sources. As discussed
previously, the majority of birds killed by collisions with communications towers are migratory
neotropical songbirds. The other sources represented in Table 6 also result in mortality to neotropical
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Cumulative Impacts
migratory songbirds although there is not clear evidence of the percentages of songbirds that are included
in the totals.
As shown in Figure 14, communications towers contribute a very small percentage (0.3 percent) of annual
avian mortality, especially when compared to other anthropogenic sources and predation by cats. Under
the No Action Alternative, migratory bird mortality levels at towers would be expected to increase in
proportion to the number of towers being built. It is anticipated that avian mortality from other
anthropogenic sources will also increase in the future as more buildings are constructed, more
automobiles and planes are in use, and more transmission lines and wind turbines are constructed.
Therefore, the proportion of bird mortality that is from communications towers, as compared to other
anthropogenic sources and predation by cats, is expected to remain relatively constant at about 0.3%
under the No Action Alternative. This proportion is expected to decrease to at least some extent under
Alternative 1 or any option of Alternative 2 because there would be fewer bird deaths at communications
towers.

Figure 14: Summary of Annual Avian Mortality by Source

Note: Figure 14 is based on the following mortality estimates:
Cats (Dauphiné and Cooper 2009)
1,000,000,000
Buildings/Windows (Klem et al. 2009)
1,000,000,000
Power Lines (Erickson et al. 2005)
130,000,000
Hunting (Klem et al. 2009)
120,000,000
Automobiles (Klem et al. 2009)
60,000,000
Pesticides (Erickson et al. 2005)
67,000,000
Communications Towers (Longcore et al. 2012 in press)
6,600,000
Wind Turbines (Klem et al. 2009)
400,000
Planes (Erickson et al. 2005)
25,000

TOTAL

2,384,025,000
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Cumulative Impacts
Human-caused mortality occurs in the context of a high level of natural mortality to bird populations
during migration. It is fairly well-documented that a large percentage of migratory birds die during
migration. Sources of mortality include lack of sufficient stopover habitat, predation, and exhaustion.
For example, Sillett and Holmes (2002) found that 85 percent of the population of Black-throated Blue
Warblers dies annually during migration. The extent to which migratory bird deaths from human sources
and cat predation are incremental to those that would have otherwise occurred is not well understood.
Therefore, although the number of birds killed each year by communications towers and other
anthropogenic sources, as well as predation by cats, is large, the impact of these deaths on the overall
mortality rate in the context of high natural mortality is likely much smaller.
6.5 SUMMARY
Migratory birds experience cumulative adverse impacts from a variety of sources, including
communications towers registered under the existing ASR Program, cat predation, and collisions with
buildings and power lines. Migratory birds are also affected by climate change, which is causing shifts in
the ranges of some species and changes in habitat conditions.
While communications towers contribute to the overall adverse impacts of all human activities on bird
populations, communications tower collisions are only responsible for approximately 0.3 percent of the
more than 2 billion annual bird deaths that currently occur due to cat predation and anthropogenic
sources. In addition, these deaths occur against a backdrop of high natural mortality to bird populations
during migration due to a number of factors. Indeed, communications tower collisions annually kill
approximately 0.07 percent of the total migratory bird population (6.6 million out of 10 billion).
Although the absolute number of birds killed at communications towers is large, towers are a relatively
minor contributor to total human-caused avian mortality, and the impact of these deaths is likely even
smaller when considered in the context of high natural mortality.
Chapter 7 of this PEA contains findings regarding the significance of the incremental impact of the ASR
program when added to other sources of avian mortality.
6-6

Findings

SECTION SEVEN

FINDINGS

7.1 OVERVIEW
Communications towers exist throughout the United States and territories and will continue to be
constructed as they provide a range of public benefits and fulfill a variety of societal needs.
Environmental impacts from towers are dependent on a variety of factors including location, height,
structural support system (self-supported or guyed), and lighting scheme (flashing or steady-burning).
The principal adverse impact of communications towers is on birds, especially migratory birds, and tower
lighting is the primary contributor to bird mortality from towers. Based on a review of the available peer-
reviewed literature and the analysis contained in this PEA, the relative severity of impacts on birds is as
follows:
·
All other factors being equal, taller towers result in higher levels of avian mortality than shorter
towers.
·
All other factors being equal, towers with guy wires result in higher levels of avian mortality than
towers without guy wires.
·
All other factors being equal, steady-burning lights on towers result in higher levels of avian
mortality than flashing lights.
These factors, as well as other potential impacts, were taken into consideration during the identification
and development of alternatives considered in this PEA.
Alternatives evaluated during this PEA process include the No Action Alternative, Alternative 1, and
three variations of Alternative 2 (Options A, B, and C). Under the No Action Alternative, the existing
ASR Program would continue with the existing FAA-permitted lighting configurations. Alternative 1
would continue the existing ASR Program but assumes that the FAA will change its permitted lighting
configurations. Alternative 2 consists of modifications to the ASR Program, with three options proposing
different revisions to the NEPA compliance procedures to improve how the potential environmental
impacts of proposed communications towers, especially impacts on migratory birds, are evaluated and
documented. Because of the importance of tower lighting to impacts on migratory birds, this chapter
presents a discussion of the options of Alternative 2 evaluated with and without the potential FAA
lighting changes.
As described at the beginning of Chapter 5, the significance of an impact must be analyzed in several
contexts and will vary with the setting of the action. Both short- and long-term effects are relevant. Once
the intensity of an impact has been determined to be negligible, minor, moderate, or major, a
determination of the impact’s significance must be made based on the requirements in 40 CFR 1508.27,
which requires considerations of both context and intensity.
As further described in Chapter 5, this PEA primarily considers the environmental effects of the ASR
Program at the national level. In addition, the PEA addresses the degree to which the FCC’s
environmental process ensures that more localized potentially significant environmental effects will be
identified and considered at each individual site. As discussed in Chapters 4 and 5, the ASR Program is
national in scale and therefore has the potential to impact resources throughout the United States, its
territories, and the District of Columbia in geographically diverse areas and previously disturbed and
undisturbed sites. Because of the wide variety of natural and manmade environments and the complexity
of resources that may be affected, it is not possible to provide a detailed comprehensive description of
resource impacts at individual sites in this PEA. Existing resources and impacts are instead characterized
in general terms and those resources that may require additional site-specific analysis are identified.
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Findings
As discussed in Chapter 5, under all alternatives the environmental impacts of the ASR Program at the
national level on resources other than migratory birds are negligible, minor, or moderate. Taking into
consideration the context and intensity of each of these impacts, the Bureau finds that none of them rises
to the level of significance. Furthermore, the existing ASR Program and all program alternatives require
EAs for towers that: would be located in an officially designated wilderness area or wildlife preserve;
may affect listed T&E species or designated critical habitat, or are likely to jeopardize the existence of
proposed T&E species or result in destruction or adverse modification of proposed critical habitat; may
affect resources listed or eligible for listing in the NRHP or Native American religious and cultural sites;
would be located in a floodplain; would involve significant changes in surface features; would be
equipped with high intensity white lights and located in a residentially zoned neighborhood; or would
cause human exposure to levels of radiofrequency radiation in excess of limits in 47 CFR §§ 1.1310 and
2.1093. The FCC will also require an EA if the processing Bureau, in response to a petition, on its own
motion, or in response to comments from the public and/or other agencies submitted during the 30-day
period for comment under the FCC’s new notice procedures, determines that an otherwise categorically
excluded action may have a significant environmental impact. These requirements ensure that potentially
significant local effects on environmental resources other than migratory birds will be identified and
considered. Accordingly, the remainder of Chapter 7 will discuss primarily impacts on migratory birds.
7.2 CONSEQUENCES OF THE NO ACTION ALTERNATIVE
The No Action Alternative is defined as continuation of the existing ASR Program and NEPA compliance
procedures, including the public notice and 30-day public comment requirement of the FCC’s recently
adopted procedures, and under the existing FAA-permitted lighting configurations.
The No Action Alternative would have no significant adverse environmental impacts at the national level
to resources described in Chapter 4, including migratory birds, although there could be significant impacts
to migratory birds, Bald Eagles, or Golden Eagles at the local level that would not be addressed. At the
national level, major adverse impacts on migratory birds due to construction in areas of heavy migration
use (coastal zones, ridgelines, bird staging areas, colonial nesting sites, WHSRN sites, and riparian zones)
would continue. Avian mortality would be expected to increase in proportion to the number and types of
new towers that are constructed. Current annual avian mortality from existing communications towers is
estimated at approximately 6.6 million birds, the majority of which are migratory birds. Assuming that
approximately 2,800 new towers would be constructed annually under the existing ASR Program, avian
mortality would increase to an estimated 8.6 million birds by the year 2022 as a result of collisions with
communications towers. While this number is large and constitutes a major impact, it is only 0.07 percent
of the overall U.S. bird population, which is estimated at 10 billion birds. Furthermore, when evaluated in
context with other sources of avian mortality as described in Sections 4.6.3.11 and 6.4.4, towers cause
approximately 0.3 percent of annual avian mortality. Thus, in the national context of overall migratory
bird abundance and other, greater forces to which migratory birds are subject, the relative impact of
communications towers is small. In addition, the available scientific information does not support a
finding that tower collisions may have a significant impact on any particular species. Therefore, the
impact to migratory birds at the national level from the No Action Alternative is not significant.
In a local context, site-specific EAs are required when existing ASR program criteria are triggered.
Migratory bird habitat features (ridgelines, coastal zones, bird staging areas, colonial nesting sites,
WHSRN sites, and riparian zones) and tower features (height, lighting scheme, and guy wires) which may
pose a greater risk of harm to migratory birds, as well as location in important Bald and Golden Eagle use
areas, are not routinely considered under the current program in determining whether an EA is required.
Therefore, there may be instances in which potentially significant impacts to a local population of
migratory birds, Bald Eagles, or Golden Eagles would not be addressed.
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Findings
7.3 CONSEQUENCES OF ALTERNATIVE 1
Under Alternative 1, continuation of the existing ASR Program with revisions to the FAA lighting
circular, there would be no significant adverse environmental impacts at the national level to resources
described in Chapter 4, including migratory birds, although there could be significant impacts to
migratory birds, Bald Eagles, or Golden Eagles at the local level that would not be addressed. At the
national level, major adverse impacts on migratory birds due to construction in areas of heavy migration
use (coastal zones, ridgelines, bird staging areas, colonial nesting sites, WHSRN sites, and riparian zones)
would continue. Avian mortality due to bird collisions with communications towers would increase in
proportion to the number and types of new towers that are constructed. However, the increase in avian
mortality due to new tower construction would be greatly reduced by the FAA lighting circular revisions.
Under these revisions, future towers that use red flashing lights would not also have steady-burning lights.
A tower without red steady-burning lights is estimated to result in 50 to 70 percent less avian mortality
than if it uses red steady-burning lights (Gehring et al. 2009). Therefore, bird mortality would decrease
under this alternative when compared to future conditions under the No Action Alternative. In addition,
tower owners would have an economic incentive to voluntarily change (or extinguish) red steady-burning
lights on existing towers and use flashing lights exclusively in order to reduce energy and maintenance
costs, thereby further reducing migratory bird mortality. Therefore, under Alternative 1, the impact to
migratory birds at the national level is not significant.
In the local context, as is the case with the No Action Alternative, site-specific NEPA documents would
be required under Alternative 1 when existing ASR program criteria are triggered. Migratory bird habitat
features (ridgelines, coastal zones, bird staging areas, colonial nesting sites, WHSRN sites, and riparian
zones) and tower features (height, lighting scheme, and guy wires) which may pose a greater risk of harm
to migratory birds, as well as location in important Bald and Golden Eagle use areas, are not routinely
considered under the current program in determining whether an EA is required. Therefore, there may be
instances in which potentially significant impacts to a local population of migratory birds, Bald Eagles, or
Golden Eagles would not be addressed.
7.4 CONSEQUENCES OF ALTERNATIVE 2 OPTION A
Alternative 2 Option A would require an EA for all new towers outside of an antenna farm submitted for
registration – regardless of location, height, use of guy wires, or lighting scheme – and for certain
structural and lighting changes to existing towers. Because virtually all new proposed tower construction
would require an EA, economic impacts on applicants would be adverse and moderate, due to increased
EA preparation costs and extended project schedules.
Under Option A, there would be no significant adverse environmental impacts at the national level to
resources described in Chapter 4, including migratory birds, and the possibility of significant
environmental impacts at the local level would be addressed for all ASR applications. Major adverse
impacts to migratory birds would continue and avian mortality would be expected to increase in
proportion to the number and types of towers that are constructed.
With no revisions to the FAA lighting circular, potential impacts to migratory birds at the national level
would be reduced to a limited extent when compared with the No Action Alternative because of
mitigation measures that would result from the EA process. Therefore, under Option A without revisions
to the lighting circular the impact to migratory birds is not significant at the national level for the same
reasons as discussed under the No Action Alternative.
Under Option A with potential revisions to the FAA lighting circular, as under Alternative 1, the increase
in avian mortality due to new tower construction would be greatly reduced because future towers that use
red flashing lights would not also have red steady-burning lights. A tower without red steady-burning
lights is estimated to cause 50 to 70 percent less avian mortality than if it uses red steady-burning lights
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Findings
(Gehring et al. 2009). In addition, tower owners would have an economic incentive to voluntarily change
(or extinguish) red-steady burning lights on existing towers and use flashing lights exclusively in order to
reduce energy and maintenance costs. Removing red steady lights would have the additional benefit of
reducing potential impacts to migratory birds. Potential impacts to migratory birds would be further
reduced to a limited extent when compared with Alternative 1 because of mitigation measures that would
result from the EA process. Therefore, under Option A, with revisions to the FAA lighting circular, the
impact to migratory birds is not significant at the national level.
In the local context, with or without revisions to the FAA lighting circular, under Option A the
preparation of site-specific EAs for all new tower construction would include an evaluation of potential
impacts to migratory birds, including individual species of migratory birds to the extent that species-
specific information exists. The EA would also include an evaluation of potential impacts to Bald and
Golden Eagles. This evaluation would ensure that potentially significant environmental impacts from an
individual tower on migratory birds and Bald and Golden Eagles would be addressed at the local level.
7.5 CONSEQUENCES OF ALTERNATIVE 2 OPTION B
Under Alternative 2 Option B, a proposed new tower would require preparation of an EA only under
certain combinations of location and structural and lighting features. Any proposed new registered tower
that requires an EA under the existing rules would require an EA. Also, if a new tower would be
constructed in an important eagle use area, the applicant would have to coordinate with USFWS in
preparing a site-specific EA. Other locational features for which a project may require an EA would
include ridgelines, coastal zones, bird staging areas, colonial nesting sites, and WHSRNs. If any of those
locational features are present, and a tower would be more than 450 feet (137 meters) tall, would use a red
steady-burning lighting scheme, or would use guy wires, an EA would be required. In addition, the FCC
would expect the EA for any proposed tower in a wetland or floodplain to include a detailed analysis of
the effects on migratory birds if the tower location is in a riparian zone. Due to the additional tower
construction projects that would require an EA, economic impacts on applicants arising from EA
preparation costs and extended project schedules would be adverse and minor.
Under Alternative 2 Option B, there would be no significant adverse environmental impacts the national
level to resources described in Chapter 4, including migratory birds, and the potential for significant
environmental impacts at the local level would be addressed in the context of site-specific EAs. Major
adverse impacts to migratory birds would continue and avian mortality would be expected to increase in
proportion to the number and types of towers that are constructed.
Without revisions to the FAA lighting circular, impacts to migratory birds at the national level would be
reduced slightly compared to the No Action Alternative, to an extent at least comparable to Option A.
Under Option B, applicants would have an incentive to avoid siting towers that are over 450 feet (137
meters) tall, use red steady-burning lights, or use guy wires; and that are located on ridgelines, in coastal
zones, in bird staging areas, in colonial nesting sites, in WHSRN sites, or in riparian zones within
wetlands and floodplains. Therefore, towers with the features that pose the greatest risk of harm to
migratory birds would be less likely to be constructed in the locations where migratory birds are most
prevalent. Applicants would also likely attempt to avoid constructing any towers in important eagle use
areas to avoid having to prepare a site-specific EA. Potential impacts to migratory birds and Bald and
Golden Eagles may be reduced when compared with the No Action Alternative because of mitigation
measures that would result from the EA process. Therefore, under Option B without revisions to the FAA
lighting circular the impact to migratory birds is not significant at the national level.
With potential revisions to the FAA lighting circular, as under Alternative 1, impacts to migratory birds
would be greatly reduced compared to the No Action Alternative because future towers that use red
flashing lights would not also have steady-burning lights. A tower without red steady-burning lights is
estimated to cause 50 to 70 percent less avian mortality than if it uses red steady-burning lights. Due to
7-4

Findings
economic incentives (reduced energy and maintenance costs), tower owners may also voluntarily change
(or extinguish) steady-burning lights on existing towers and use flashing lights exclusively, thereby
further reducing migratory bird mortality. Avian mortality would be further slightly reduced because the
Bureau anticipates that applicants would likely attempt to avoid constructing towers that are taller than
450 feet (137 meters) tall or use guy wires in areas important to migratory birds, and to avoid constructing
any towers in important Bald and Golden Eagle use areas. Overall, migratory bird mortality would be
less than under Alternative 1 and comparable to Option A with revisions to the FAA lighting circular.
Therefore, under Option B with revisions to the FAA lighting circular the impact to migratory birds is not
significant at the national level.
In the local context, with or without revisions to the FAA lighting circular, EAs would be required under
Option B for towers with the features that contribute the most to migratory bird deaths if they are located
in the areas where migratory birds are most prevalent. These EAs would include an evaluation of
potential impacts to individual species of migratory birds to the extent that species-specific information
exists. In addition, EAs would be required for all towers in important Bald and Golden Eagle use areas.
These requirements would ensure that potentially significant environmental effects on migratory birds and
Bald and Golden Eagles at the local level would be addressed.
7.6 CONSEQUENCES OF ALTERNATIVE 2 OPTION C
Under Alternative 2 Option C, in addition to those towers for which an EA is required under the existing
FCC rules, an EA would be required for any proposed new tower, or replacement or modification of an
existing tower that involves a substantial increase in size, that is more than 450 feet (137 meters) tall,
regardless of location, lighting scheme, or use of guy wires. Towers less than or equal to 450 feet (137
meters) would be categorically excluded unless they would require an EA under the existing rules.
Under Alternative 2 Option C, there would be no significant adverse environmental impacts at the
national level to resources described in Chapter 4, including migratory birds, although there could be
significant impacts to migratory birds, Bald Eagles, or Golden Eagles at the local level that would not be
addressed. At the national level, major adverse impacts on migratory birds due to construction in areas of
heavy migration use (coastal zones, ridgelines, bird staging areas, colonial nesting sites, and WHSRN
sites) would continue. Avian mortality would be expected to increase in proportion to the number and
types of towers that are constructed.
Without revisions to the FAA lighting circular, avian mortality at the national level would be reduced
compared to the No Action Alternative because applicants would have an incentive to avoid constructing
towers over 450 feet (137 meters) tall to the extent practicable. However, in many instances it is unlikely,
particularly for broadcast towers, that such a tower could be reduced appreciably in height and still be
able to meet service coverage requirements. Because Options A and B would require EAs for more
towers that may affect migratory birds, Option C would not reduce potential impacts to migratory birds as
much as those two options. However, potential impacts to migratory birds may be reduced when
compared with the No Action Alternative because of mitigation measures that would come out of the EA
process for towers more than 450 feet (137 meters) tall. Therefore, the impact to migratory birds is not
significant at the national level for the same reasons as discussed under the No Action Alternative.
Under Option C, with the potential revisions to the FAA lighting circular, as under Alternative 1, impacts
to migratory birds would be greatly reduced compared to the No Action Alternative because future towers
that use red flashing lights would not also have steady-burning lights. A tower without red steady-
burning lights is estimated to cause 50 to 70 percent less avian mortality than if it uses red steady-burning
lights. In addition, due to economic incentives (reduced energy and maintenance costs), tower owners
may voluntarily change (or extinguish) steady-burning lights on existing towers and use flashing lights
exclusively, thereby further reducing migratory bird mortality. Avian mortality would be further slightly
reduced because applicants would have an incentive to avoid constructing towers over 450 feet (137
7-5

Findings
meters) tall where feasible, and because of mitigation measures that may come out of the EA process for
towers more than 450 feet (137 meters) tall. Overall, the reduction in migratory bird deaths would be
more than under Alternative 1, but less than under Option A or Option B with revisions to the FAA
circular.
In the local context, with or without revisions to the FAA circular, site-specific NEPA documents would
be required under Option C when existing ASR program criteria are triggered or when a proposed tower
would be more than 450 feet (137 meters) tall. Except for tower height, migratory bird habitat features
(ridgelines, coastal zones, bird staging areas, colonial nesting sites, and WHSRN sites) and tower features
(lighting scheme and guy wires) which pose a greater risk of harm to migratory birds, as well as location
in important Bald and Golden Eagle use areas, would not be routinely considered under Option C in
determining whether an EA is required. Therefore, there may be instances in which potentially
significant impacts to a local population of migratory birds, Bald Eagles, or Golden Eagles would not be
addressed.
7.7 CUMULATIVE IMPACTS
When applying the concept of cumulative impacts to a programmatic analysis, some additional
consideration must be given to existing uncertainty associated with specific locations that will be selected
in the future. Communications towers could be proposed anywhere within the United States including its
territories. Therefore, this PEA addresses cumulative impacts qualitatively.
From a cumulative impacts perspective, under the No Action Alternative, Alternative 1, or any option of
Alternative 2, towers regulated under the ASR Program will continue to cause migratory bird deaths.
Migratory bird deaths due to collisions with communications towers are currently estimated at 6.6 million
per year, and depending on the alternative chosen, this number is expected to be between 4.9 million and
8.6 million in 2022. If the FAA does not change its lighting circular, under all alternatives there will be
an incremental increase in avian mortality over existing conditions. If the FAA revises its lighting
circular, there may be an increase or a decrease in avian mortality depending on the extent to which tower
owners voluntarily change (or extinguish) steady-burning lights on existing towers and use flashing lights
exclusively.
In assessing cumulative impacts on a resource, the incremental impacts of the action in question are
considered together with the impacts of other past, present, and reasonably foreseeable future actions.
Anthropogenic sources and cat predation together annually kill a relatively large percentage of the U.S.
migratory bird population (more than 2 billion out of 10 to 20 billion), and an increase in this mortality
could therefore be cumulatively significant. Determination of whether a particular increase in this
mortality does rise to the level of cumulative significance requires consideration of all the facts.
For several reasons, the Bureau concludes that the additional migratory bird deaths caused by
communications towers are not cumulatively significant at the national level. First, the estimated 6.6
million annual bird deaths caused by communications towers constitute only approximately 0.3 percent of
the total bird deaths attributable to anthropogenic sources and cat predation. Thus, the incremental
mortality that these deaths add to the total avian mortality attributable to human actions is relatively not
large. In addition, these deaths occur against a backdrop of high natural mortality to migrating birds due
to a number of factors. Indeed, annual avian deaths attributable to towers constitute approximately 0.07
percent of the migratory bird population. Taking all these factors together, the incremental impact of the
ASR Program on migratory birds, considered in context and together with the impacts of other past,
present, and reasonably foreseeable future actions, is not cumulatively significant nationally.
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Findings
7.8 SUMMARY
The impacts of the ASR Program at the national level on all resources, including migratory birds, are not
significant. However, depending on the alternative selected, there may be instances in which potentially
significant impacts to a local population of migratory birds, Bald Eagles, or Golden Eagles would not be
addressed.
At the national level, the best available and most current estimate of avian mortality, primarily to
migratory birds, from collisions with communications towers is 6.6 million birds annually. Tall towers,
steady-burning lights, and guy wires are the primary tower characteristics contributing to avian mortality.
Migratory bird mortality from all sources would be expected to increase in the future, with an anticipated
increase in the number of vertical structures in the environment as well as continuing impacts from other
actions and factors. The construction of new communications towers would contribute incrementally to
this future increase in mortality, regardless of whether FAA lighting changes are implemented.
The Bureau recognizes that the potential changes to the FAA lighting circular would have the greatest
beneficial effect and be the critical element in reducing impacts to migratory birds under any of the
alternatives. Under Alternative 1 (which assumes FAA lighting changes will occur) and any of the options
under Alternative 2 (if FAA lighting changes occur), the incremental increase in migratory bird mortality
from new towers approved under the ASR Program would be substantially reduced due to the use on
future towers of red flashing lights exclusively without red steady-burning lights. Studies indicate that the
use of flashing lights on towers may reduce bird mortality at towers by 50 to 70 percent (Gehring et al.
2009). In addition, voluntary lighting changes on existing towers from steady-burning to flashing lights
would further reduce migratory bird impacts and may possibly reduce the total number of bird deaths
from registered towers below current levels.
The Bureau acknowledges that the estimated bird mortality as a result of collisions with towers approved
under its ASR Program is a large number. However, the anticipated annual bird mortality from existing
and future communications towers under any alternative is not significant at the national level, whether
considered as a separate, direct impact or as part of a cumulative analysis.
At the site-specific level, under Options A and B of Alternative 2, the requirements to prepare EAs for
individual towers would ensure that potentially significant effects on local migratory bird and Bald and
Golden Eagle populations would be considered. Under the No Action Alternative, Alternative 1, and
Option C of Alternative 2, potentially significant impacts on local migratory bird and Bald and Golden
Eagle populations may not be addressed.
Very little reliable information is available with regard to species-specific impacts as a result of tower
collisions. While information on species-specific effects would be relevant to the analysis presented in
this PEA, it would be infeasible and unreasonably costly for the FCC to generate such data on each of the
1,007 migratory species, or even on the 147 nationally identified BCC species. Effects of individual
towers on threatened and endangered species are considered under the FCC’s existing procedures. To the
extent that evidence exists regarding the effects of individual towers on other avian species, such evidence
will be considered in EAs where required under any Option of Alternative 2, and may be raised through
the FCC’s notice process.
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Mitigation

SECTION EIGHT

MITIGATION

8.1 OVERVIEW
Under the No Action Alternative, Alternative 1, and all options of Alternative 2, the FCC could require
mitigation of potentially significant local environmental effects through the preparation and review of
EAs for individual towers. The FCC is also engaged in programmatic consultation with the USFWS to
consider potential further measures to protect T&E species. The Bureau encourages tower owners and
applicants to consider additional measures that may further mitigate any environmental effects.
8.2 MITIGATION ARISING FROM THE EA PROCESS FOR INDIVIDUAL TOWERS
Under the No Action Alternative, Alternative 1, and all options of Alternative 2, EAs would be required
where certain conditions are met. The EA preparation and review (and any subsequent EIS, where
necessary) would include consideration of measures to avoid or mitigate environmental effects that may
result from these conditions. The following conditions would require an EA under the No Action
Alternative, Alternative 1, and all options of Alternative 2:
·
The tower would be located in an officially designated wilderness area or wildlife preserve;
·
The tower may affect listed T&E species or designated critical habitat, or is likely to jeopardize
the continued existence of proposed T&E species or result in destruction or adverse modification
of proposed critical habitat. The FCC requires consultation with the USFWS where there is a
potential for such an impact;
·
The tower may affect resources listed or eligible for listing in the NRHP. The Nationwide
Programmatic Agreement (NPA) sets forth a specific process for considering such effects,
including review by the SHPO/THPO, and requires an MOA setting forth mitigation where there
would be an adverse effect on historic properties;
·
The tower may affect an Indian religious site. The NPA sets forth specific procedures for inviting
the participation of federally recognized Indian Tribes and Native Hawaiian organizations. The
FCC encourages use of its Tower Construction Notification System to fulfill these requirements;
·
The tower would be located in a floodplain;
·
The tower would involve significant changes in surface features (e.g., wetland fill, deforestation,
or water diversion);
·
The tower would be equipped with high intensity white lights and located in a residentially zoned
neighborhood; or
·
The facility would cause human exposure to levels of RF radiation in excess of the FCC’s
guidelines.
Further, if the Bureau, in response to a petition, on its own motion, or in response to comments from the
public and/or other agencies submitted during the 30-day period for comment under the FCC’s new notice
procedures, determines that an otherwise categorically excluded action has a potentially significant
environmental impact, the applicant would have to prepare an EA.
Under all options of Alternative 2, EAs also would be required in additional circumstances, which would
ensure consideration of measures to avoid or mitigate any effects of these towers on migratory birds,
including Bald and Golden Eagles. Through review of these EAs, the FCC would ensure consultation
with the USFWS in appropriate cases.
8-1

Mitigation
Under Option A of Alternative 2, EAs would be required for all new towers and for replacements and
modifications of towers that involve a substantial increase in size. This process would afford an
opportunity to consider measures to avoid or mitigate any environmental effects.
Under Option B of Alternative 2, EAs would also be required for new towers, and for replacements and
modifications of towers that involve a substantial increase in size, under the following circumstances:
·
The tower would use guy wires, would be equipped with red steady-burning lights, or would be
over 450 feet (137 meters) in height

AND

would be located in a coastal zone, on a ridgeline, or in
a bird staging area, colonial nesting site, or WHSRN site; or
·
The tower would be located within an important eagle use area.
In addition, an EA prepared for a tower that is over 450 feet (137 meters) in height, uses red steady-
burning lights, or uses guy wires and is located in a riparian zone within a wetland or floodplain would be
expected to include a detailed analysis of the tower’s effects on migratory birds. This process would
ensure consideration of measures to mitigate any environmental effects caused by these conditions,
especially effects on migratory birds.
Under Option C of Alternative 2, EAs would also be required for new towers, and for replacements and
modifications of towers that involve a substantial increase in size, where the tower would be greater than
450 feet (137 meters) in height.
8.3 ADDITIONAL MITIGATING MEASURE BY THE FCC
The FCC has recently entered into programmatic consultation with the USFWS under Section 7(a)(1) of
the ESA. This consultation is expected to result in an evaluation of the degree to which the ASR Program
contributes to furthering the purposes of the ESA, along with possible recommendations to improve or
enhance this contribution, as well as a description of any subsequent consultation that may be required
between the USFWS and the FCC at a less aggregated regional or local scale.
8.4 ADDITIONAL RECOMMENDATIONS FOR APPLICANTS
The Bureau encourages tower owners and applicants to consider the following measures:
·
Eliminate red steady-burning lights on existing towers where permitted by the FAA if lighting
circular is revised.
·
Where feasible, collocate antenna(s) on existing towers or other structures in place of new tower
construction.
·
Where feasible, site new towers within an existing antenna farm.
·
Minimize tower height and tower foundation footprint to the extent feasible consistent with
coverage and structural safety requirements, taking into account that greater tower height may
facilitate additional collocations.
·
Construct self-supported structures, rather than those that require guy wires, to the extent
technically and economically feasible, taking into account that in some situations self-supported
structures may have greater visual impacts on cultural or other visual resources.
·
Where feasible, avoid siting new towers in avian high use areas, including coastal zones,
ridgelines, bird staging areas, colonial nesting sites, WHSRN sites, and riparian zones.
·
Where feasible, protect a minimum 2-mile (3.2-kilometer) radius of sagebrush around known leks
for grouse and prairie-chickens.
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Mitigation
·
Select new tower sites in areas with existing visual clutter where feasible and use vegetative
screening to reduce visual impacts.
·
Use standard best management practices for sediment erosion control to minimize impacts to
downstream surface waters and wetlands.
·
Use standard best management practices to prevent or minimize the establishment and spread of
non-native invasive species.
·
During construction, keep fuel-burning equipment running times to a minimum and properly
maintain engines.
·
Perform construction activities during day-time business hours.
·
Minimize and down-shield security lighting for on-ground facilities and equipment to avoid
attracting night-migrating birds.
·
Decommission and remove obsolete or unused towers.
·
Support monitoring and other forms of research on the effects of towers on birds (especially BCC
species) and other wildlife, including potential RF radiation effects.
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Comments on Draft PEA

SECTION NINE

PUBLIC COMMENTS ON DRAFT PEA

9.1 OVERVIEW
The Draft PEA was made available for public review on August 26, 2011. The Draft PEA was available
http://www.fcc.gov/encyclopedia/programmatic-environmental-assessment-pea">electronically on the FCC website at http://www.fcc.gov/encyclopedia/programmatic-environmental-
assessment-pea, and paper copies were available upon request. As requested by USFWS and conservation
groups, the deadline for comments was extended from October 3 until November 2, 2011. Thirteen
comments were received on the PEA. Comments were received from the following:

Agencies

·
U.S. Fish and Wildlife Service

Organizations/Academia

·
Conservation Groups (American Bird Conservancy, Defenders of Wildlife, and National
Audubon Society)
·
Dr. Joelle Gehring, Michigan State University
·
Dr. Travis Longcore, The Urban Wildlands Group, Inc.

Industry

·
American Cable Association
·
APCO International
·
AT&T Inc.
·
Infrastructure Coalition (CTIA–The Wireless Association®, the National Association of
Broadcasters, the National Association of Tower Erectors, and PCIA–The Wireless Infrastructure
Association)
·
National Public Radio
·
NTCH Inc.
·
Utilities Telecom Council
·
Verizon Wireless

Individuals

·
William McMullin
All comments submitted are available for review on the FCC website noted above. All comments
submitted can be viewed under Docket No. 08-61 (National Environmental Policy Act Compliance for
Proposed Tower Registrations) and Docket No. 03-187 (Effects of Communications Towers on Migratory
Birds).
9.2 SUMMARY OF COMMENTS RECEIVED AND BUREAU RESPONSES
Substantive comments are summarized here and presented by the chapter of the PEA to which they refer,
along with the Bureau response.
9-1

Comments on Draft PEA
9.2.1 Chapter 1 – Introduction

Comment 1.1

: The FCC should invite Federal land management agencies and state and Tribal wildlife
agencies to be cooperating agencies.

Response 1.1

: Interested agencies have had ample opportunity to provide input through the scoping
process, as well as through the 60-day period provided for agency and public review of the draft PEA.
Engaging multiple entities from across the nation as formal cooperating agencies would add substantial
time and expense to preparing the PEA, and is neither warranted nor necessary.

Comment 1.2

: The Proposed Action should be defined as an ASR Program that complies with all
applicable environmental laws.

Response 1.2

: The description of the Proposed Action in the PEA has been clarified to read, in part:

The Proposed Action is to modify the ASR Program and associated NEPA compliance procedures
as necessary to ensure compliance with NEPA and other applicable environmental laws.


9.2.2 Chapter 2 – Purpose and Need

Comment 2.1

: The purpose and need for the action is to comply with all applicable laws and to reduce
adverse effects to migratory birds caused by communications towers.

Response 2.1

: The purpose of an action is defined as what the action is intended to do. The purpose of
the Proposed Action has been revised to clarify that it is intended to ensure that the ASR Program
complies with NEPA and applicable environmental regulations and to reduce its impacts on migratory
birds, to the extent consistent with the Commission’s authority under the Communications Act.
The need for the action is why the action is being proposed. The PEA correctly states that revisions to the
environmental review process under the ASR Program need to be considered to ensure that the FCC
complies with its obligations under NEPA.
9.2.3 Chapter 3 – Alternatives

Comment 3.1

: In addition to ridgelines, coastal zones, and bird staging areas, the FCC should avoid
placing towers in Western Hemisphere Shorebird Reserve Network (WHSRN) sites.

Response 3.1

: Alternative 2 Option B has been revised to add WHSRN sites to the list of migratory bird
habitat features which may trigger a site-specific EA.

Comment 3.2

: The FCC should preclude development in important eagle use areas without coordination
with USFWS.

Response 3.2

: Alternative 2 Option B has been revised to incorporate this change.

Comment 3.3

: The FCC should define larger classes of categorically excluded actions by incorporating
mitigative measures into the applications. The PEA may serve to increase the number of NEPA
documents required without an expectation that doing so would reduce impacts.

Response 3.3

: The various alternatives considered in the PEA appropriately define categorically excluded
actions based on the potential effects of towers on migratory birds and other environmental resources.
Using mitigation to define categorical exclusions would be inconsistent with NEPA, under which an
agency must first determine if an action will have a significant impact and then, if so, consider
appropriate mitigation. If mitigation were made the trigger for NEPA evaluation, then some towers would
become subject to mitigation even though they do not need it because they would not have a significant
impact in any event, and other towers might escape NEPA evaluation even though they still have a
significant impact after mitigation.
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Comments on Draft PEA

Comment 3.4

: Alternative 2 Option B should be revised to replace the last “AND” in the description with
“OR.”

Response 3.4

: Changing “AND” to “OR” in Alternative 2 Option B, particularly in the absence of any
changes to the FAA guidelines, would result in an alternative comparable to Alternative 2 Option A. Such
an alternative may result in fewer migratory bird deaths, but it is not necessary to avoid potentially
significant environmental impacts.

Comment 3.5

: Although shorter towers are not involved in as many avian fatalities as tall towers
(Gehring et al. 2009), cumulatively the shorter towers contribute to a large number of avian fatalities
(Kerlinger et al. in final review).

Response 3.5

: As explained in Section 5.4.3.3 of the PEA, towers that exceed 984 feet (300 meters) cause
69 percent of mortality to migratory birds, and over 84 percent of mortality is caused by towers that
exceed 490 feet (150 meters) (Longcore 2012 in press). Less than 16 percent of avian mortality is caused
by towers less than 490 feet (150 meters) tall. Therefore, it is appropriate under Alternative 2 Option C to
consider categorically excluding towers less than 450 feet (137 meters) tall unless another trigger for an
EA is present, and under Alternative 2 Option B to use a height of 450 feet (137 meters) as one criterion
for triggering an EA in higher-risk locations. Alternative 2 Option A requires an evaluation of the effect
that every tower has on migratory birds.

Comment 3.6

: The PEA fails to address or motivate any changes to existing towers that would decrease
avian collisions and there is no discussion of how the ASR Program might provide incentives for changes
to existing towers. Also, the PEA assumes, without elaboration, that the dictates of technology limit the
range of options to be reviewed.

Response 3.6

: Because NEPA provides for environmental review only of proposed major federal actions,
the PEA considers changes to the FCC’s processes and requirements only for new or modified towers.
Alternative 1 and all options of Alternative 2 do address whether changes in lighting on existing towers
would decrease avian collisions, and the discussion of these alternatives has been clarified to explain that
tower owners would have an incentive voluntarily to change (or extinguish) red steady-burning lights on
existing towers and use flashing lights exclusively, if permitted under FAA guidance, in order to reduce
their energy and maintenance costs. In Chapter 8 of the PEA, the Bureau encourages tower owners and
applicants to consider various mitigation measures to reduce avian collisions, including the use of
flashing lights on existing towers to the extent permitted by the FAA; several of these measures were
taken from the USFWS Guidelines for Communications Towers.
As described in Section 3.4, Alternatives Considered and Dismissed, other changes to existing towers
(reducing tower height, prohibiting towers in certain locations, and prohibiting guy wires on new towers)
are ordinarily not feasible or economically reasonable.

Comment 3.7

: The PEA requires a more specific and detailed definition of the term “antenna farm.”

Response 3.7

: As defined in Section 1.1306, Note 3 of the FCC rules, an antenna farm is "an area in
which similar antenna towers are clustered, whether or not such area has been officially designated as an
antenna farm." This definition has been added to the PEA.

Comment 3.8

: The PEA ignores CEQ’s final guidance to review/revise categorical exclusions.

Response 3.8

: Alternative 2 proposes various options for reviewing/revising the FCC’s categorical
exclusions. Actual revisions will require a formal rulemaking process, which would occur after the
release of the final PEA.

Comment 3.9

: The assumptions regarding existing towers and future needs and trends limit the range of
alternatives presented and undermine the reliability of the PEA’s analysis.
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Comments on Draft PEA

Response 3.9

: The Bureau met with CEQ prior to preparing the PEA to discuss its approach to
developing alternatives. The Bureau’s basis for its assumptions is discussed in the PEA.

Comment 3.10

: The alternatives analysis does not comply with CEQ guidance because it fails to
rigorously and objectively evaluate all reasonable alternatives. For example, there is no alternative to
address the impacts of the 5,000+ existing towers (over 450 feet [137 meters] tall) on migratory birds.

Response 3.10

: With the number of different factors that may affect impacts on migratory birds, the PEA
had an almost limitless range of alternatives available for consideration. The purpose and need define
what can be considered reasonable, prudent, and practicable alternatives. The alternatives evaluated in the
PEA meet the court-determined purpose and need, and include a wide range of possibilities. With regard
to the impacts of existing towers, see Response 3.6, above.

Comment 3.11

: To comply with CEQ guidance, the No Action Alternative should have been the existing
program, which does not include the not-yet-adopted new notice and interim regulations.

Response 3.11

: The draft procedures were adopted by the Commission on December 6, 2011 (FCC
2011b), and text throughout the PEA has been revised as needed. The No Action Alternative is the
continuation of the existing ASR Program and NEPA compliance procedures, including the public notice
and 30-day public comment requirement.

Comment 3.12

: A reasonable alternative could be based on the USFWS Guidelines for Siting and
Management of Communications Towers by including the Guidelines as a part of the ASR compliance
process (if FAA revises its lighting circular, the Guidelines would be updated to reflect the revised
circular). For example, if applicants follow the Guidelines, their project would be categorically excluded;
if they do not follow the Guidelines, they would be required to prepare an EA.

Response 3.12

: Many elements of the Guidelines are incorporated into the alternatives considered and the
mitigation measures recommended in Chapter 8. However, because of the language contained in the
Guidelines, e.g., “to the extent possible,” the guidelines do not lend themselves to adoption as a set of
criteria.
9.2.4 Chapter 4 – Affected Environment

Comment 4.1

: A 10-year time frame is selected for impact analysis but the PEA does not provide reasons
for that selection. The PEA also does not provide supporting justification for why the time frame is not
the life of the program, which should be used for the analysis of cumulative effects.

Response 4.1

: The temporal scale of analysis for the PEA begins in 1995, when the ASR Program was
instituted, and extends 10 years into the future. The Bureau recognizes that new studies and research are
being planned and conducted to examine the environmental impacts of towers, especially related to bird
collisions and impacts to migratory birds. Due to the rapidly changing technology of the
telecommunications industry and anticipated new studies examining bird and tower interactions, the PEA
encompasses a 10-year planning timeframe. A timeframe longer than 10 years would not be meaningful
because it would be difficult reliably to project future conditions, including the number of towers
anticipated to be built. The analysis in the PEA will be reviewed for adequacy should future major
changes to the ASR Program be considered or major changes to environmental conditions occur.

Comment 4.2

: The PEA mischaracterizes the source of estimates of population size by stating that
“There is some uncertainty associated with both total migratory bird populations and individual species
populations. As Longcore et al. (2011b in preparation [cited in final PEA as Longcore et al. 2011 in
preparation]) acknowledged, the population estimates they used may vary by as much as an order of
magnitude. In addition, population levels vary from year to year and geographically.”

Response 4.2

: As explained in Section 4.6.3.1 of the final PEA, the Longcore et al. study (2011 in
preparation) describes the accuracy of individual species populations as being correct within an order of
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Comments on Draft PEA
magnitude. That implies a large amount of potential variance in the abundances that are provided.
Moreover, these individual population estimates date from 2001 to 2004. As populations vary from year
to year and decade to decade, the age of the data adds another level of variance that is not acknowledged
or addressed in the manuscript (Longcore et al. 2011 in preparation).

Comment 4.3

: The PEA does not provide any evidence that the [Longcore] analysis is biased toward
overrepresentation of extreme episodic events. The PEA grossly errs in its interpretation of the content
and purpose of the meta-analysis represented in this paper by stating that: “In a draft report, Longcore et
al. (2011 in preparation) estimate that towers may disproportionately kill certain bird species when
compared to other sources of mortality. For 12 species, they estimate that mortality at towers is greater
than 1 percent of the total population size and may have an impact on population viability. They further
state that one of these species is endangered, and an additional eight species are Birds of Conservation
Concern. However, as noted above, their results were based on a meta-analysis of existing studies that
were not designed to address species-specific effects. In addition, the analysis carries an inherent bias by
including an overrepresentation of extreme episodic events that skew the mortality estimates.”

Response 4.3

: Sections 4.6.3.1 and 5.4.3.3 of the PEA have been revised to clarify the nature and sources
of the uncertainty associated with the data reported by Longcore et al. (2011 in preparation). In particular,
Section 4.6.3.1 explains that the conclusions drawn by many of the existing studies are not based on
typical conditions at a majority of tower sites. Furthermore, the Longcore et al. manuscript (2011 in
preparation) cites many tower kill studies that are 40 to 50 years old, which introduces uncertainty as to
whether the data in those studies remain valid.
9.2.5 Chapter 5 – Environmental Consequences

Comment 5.1

: Rather than assessing all birds as a single resource category for analysis, the FCC should
focus on: a) the 54 BCC species documented in tower kill literature; b) Bald and Golden Eagles; and, c)
T&E species.

Response 5.1

:
a) It is not appropriate for the significance criteria to be based on the degree of effects on BCC species,
which have no protection beyond that of other migratory birds. BCC status is relevant to the extent
that, due to the smaller populations of these birds, it is more likely that an individual BCC species
would be affected. However, with no population-specific data, these effects cannot be determined on
a species-specific basis in the PEA.
b) Impacts to Bald and Golden Eagles are addressed in Section 5.4.3.4 of the PEA.
c) Listed T&E species are protected under existing FCC rules and are addressed in Section 5.4.3.2 of the
PEA.

Comment 5.2

: The PEA includes no species-specific effects determinations or proposed conservation
measures to inform the FCC’s programmatic consultation under the ESA.

Response 5.2

: At a meeting on March 4, 2011, staff from the USFWS Endangered Species Program
proposed consultation under Section 7(a)(1) of the ESA for the ASR Program, while continuing to apply
Section 7(a)(2) to individual projects. The FCC has initiated consultation with USFWS under Section
7(a)(1) as described in correspondence dated May 3, 2011. Specific species listed as threatened or
endangered under the ESA are protected under existing FCC rules, and projects that have the potential to
impact specific listed species require coordination with USFWS and preparation of an EA. A general
discussion of impacts to listed species is provided in Section 5.4.3.2 of the PEA.

Comment 5.3

: Because no comprehensive monitoring of effects of communication towers on BCC
species has been conducted, there is a high degree of uncertainty about the effects to BCC species on a
national or regional scale, and about the effects of radiation, especially to breeding birds. The uncertainty
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Comments on Draft PEA
about these effects thus meets the significance criterion (40 CFR 1508.27[b][5]), “The degree to which
the possible effects on the human environment are highly uncertain or involve unique or unknown risks.”
Because of this and because a substantial portion of future and ongoing impacts from communications
towers are likely unavoidable and significant, the FCC should prepare a PEIS rather than finalize the
PEA.

Response 5.3

: There is little available scientific evidence as to the potential significance of the effects of
towers on individual species of migratory birds, or of impacts to birds from RF radiation emissions. A
lack of data does not necessarily translate to a high degree of uncertainty, and in this instance the
evidence is insufficient to support a finding of significant impact. The analysis conducted in the PEA is
extensive and comparable to that which would be conducted for a PEIS. Furthermore, the Court’s
decision in American Bird Conservancy, Inc. v. FCC permitted the FCC to prepare a PEA rather than a
PEIS, and the Bureau consulted with CEQ early in the process about its decision to take this approach.
While the Bureau acknowledges that information on species-specific effects would be relevant to the
analysis presented in the PEA, it would be infeasible and unreasonably costly for the FCC to generate
data on species-specific effects from communications towers nationwide on each of the 1,007 migratory
species, or even on the 147 nationally identified BCC species. Therefore, the FCC is not required to
obtain such information (40 CFR 1502.22[a]). Furthermore, to the extent evidence exists regarding the
effects of individual towers on particular avian species, that evidence would be considered in an EA
where required under any Option of Alternative 2, and may also be raised through the FCC’s notice
process. Also see Response 5.1.a above.

Comment 5.4

: The PEA fails to adequately prove that towers have no significant impact on migratory
birds and needs to consider diversity of population levels of bird species. Some populations of rare
species are more vulnerable to impacts of fatalities due to towers than species living in higher densities.

Response 5.4

: It is appropriate to assess the mortality of migratory birds in terms of total bird populations
because there is insufficient data on species-specific population levels. It is not possible to break out
tower mortality impacts on individual populations or assess environmental impacts in terms other than
total bird populations. Existing FCC rules ensure that potential impacts to federally protected T&E
species will be addressed on a site-specific basis. Also see Response 5.3 above.

Comment 5.5

: Analysis and conclusions should be based on quality, contemporary (post-2000) data.

Response 5.5

: Reasonably available literature, including many of the most recent studies, was reviewed
during preparation of the PEA. The PEA’s analysis and findings are based primarily on studies from
2005 and later.

Comment 5.6

: Appropriate data analysis must be used – simple linear regression without considering
error in estimates is unacceptable.

Response 5.6

: As reflected in the PEA, the Bureau considered the merits of each of the studies
referenced. No linear regression analysis was conducted for the PEA. While some of the studies reviewed
for the PEA may have used linear regression analysis, the Bureau did not conduct a statistical review of
these studies.

Comment 5.7

: The statement: “Towers that cause the most mortality to migratory birds are those that
exceed 1,000 feet (305) meters AGL …” is not entirely accurate.

Response 5.7

: See Response 3.5.

Comment 5.8

: It does not matter that the studies in the meta-analysis were not conducted to address
species-specific effects. One need not consider the conclusions drawn in the manuscript to reach the
conclusion that communications towers result in significant biological impact within the understanding of
NEPA.
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Comments on Draft PEA

Response 5.8

: As explained in Section 4.6.3.1, most of the studies considered in Longcore et al. (2011 in
preparation) were not designed to address species-specific effects. In addition, the analysis relies heavily
on studies that describe extreme episodic events; it draws major conclusions from very small sample
sizes; and it mixes data from widely divergent time periods during which species populations may vary
by as much as an order of magnitude (Rich et al. 2004). The study therefore does not support a conclusion
of significant biological effect.

Comment 5.9

: The Arnold and Zink (2011) results are suspect because: a) they used a flawed secondary
source (Shire et al. 2000); b) they do not account for regional variation in mortality or provide a
mechanism to combine studies of different lengths in a way that avoids large datasets overwhelming
small ones; and, c) their regression of collision risk against population trends included many trends that
were not statistically significant and the regression did not incorporate the known errors in either the
population estimates or the proportions of birds killed.

Response 5.9

: The PEA acknowledges these criticisms of Arnold and Zink (2011) and treats its findings
as relevant but not dispositive. The Bureau notes that the Shire et al. 2000 paper was prepared by the
American Bird Conservancy and that 37 of the 47 papers used in the Shire et al. study were also used in
Longcore et al. (2011 in preparation, Table 1).

Comment 5.10

: Discernable population-level impacts are not a necessary prerequisite to identifying
significant adverse impacts under NEPA. Violations of MBTA and BGEPA are identifiable significant
adverse impacts.

Response 5.10

: Potential violations of BGEPA are appropriately considered as part of any required pre-
grant environmental processing for a particular ASR application. Courts have rendered differing decisions
regarding the scope of the MBTA’s application to Federal agencies, as well as to unintentional, incidental
deaths of migratory birds.

Comment 5.11

:
a) The PEA states that “In the absence of peer review, the conclusions that Longcore et al. (2011b in
preparation [cited in final PEA as Longcore et al. 2011 in preparation]) draw from the[ir] studies are
not accorded significant weight.” This standard is only applied to Longcore et al. (2011b in
preparation). The approaches and results in this manuscript were accepted by and published as an
abstract at the 2010 American Ornithologists’ Union Conference (Longcore et al. 2010), which is
certainly [a] more rigorous review than [that] undergone by the websites that the FCC includes in the
PEA as legitimate sources. CEQ guidance and courts have held that NEPA sources need not be peer-
reviewed or published but only that the information is of high quality. The FCC should look to
USFWS to evaluate the study’s conclusions.
b) Only the conclusions in the Longcore papers have been singled out for question, when the
conclusions of other sources not published in the academic literature are accepted without question
and even relied upon by the FCC to draw its conclusions.

Response 5.11

:
a) The project team worked diligently to identify, obtain, and review relevant studies and papers (both
peer-reviewed and non-peer-reviewed) and other resources (more than 150 as of April 2011; a list of
these resources was provided at the April 2011 workshop) to inform the analysis for this PEA.
Among other studies, the Bureau reviewed the draft paper by Longcore et al. (2011 in preparation)
and considered the draft on its merits. The major weaknesses identified in the draft are that: 1) it relies
on studies that were not designed to identify species-specific effects; 2) it relies heavily on studies
that describe extreme episodic events; 3) it draws major conclusions from very small sample sizes;
and 4) it mixes data from widely divergent time periods during which species populations may vary
by as much as an order of magnitude (Rich et al. 2004). Therefore, the Bureau does not find the study
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Comments on Draft PEA
persuasive. Further, the draft provided had not completed peer review, and revisions have since been
made that were not made available to the Bureau.
b) Other papers also were assessed as having questionable analysis or results. For example, the Bureau
cites Morris et al. (2003), who report a significant decrease in the number of birds salvaged at towers
in New York and Ohio over a 30-year period. The Bureau states in the PEA that the decline in
mortality suggested by these data is best viewed as hypothetical and requires more research. The PEA
does not rely upon any single source or group of sources, published or unpublished, to develop
conclusions.

Comment 5.12

: The cultural resources analysis does not assess the effects on Bald and Golden Eagles,
which have religious, spiritual, and cultural significance to Native American Tribes.

Response 5.12

: The alternatives proposed in the PEA consider the BGEPA, which protects Bald and
Golden Eagles (see Sections 4.6.4 and 5.4.3.4). To the extent Bald and Golden Eagles have religious,
spiritual, and cultural significance that is not protected by BGEPA review, such an impact is not
programmatic in nature, but may be considered along with other cultural resources as part of a site-
specific evaluation.

Comment 5.13

: Indirect impacts should also be evaluated for species-level impacts. Indirect impacts,
when considered with identified direct impacts, may be significant enough to jeopardize the continued
existence of T&E species.

Response 5.13

: Indirect impacts are evaluated in the PEA. While indirect impacts on individual species
are relevant to NEPA analysis, in general there is insufficient evidence to evaluate such impacts on a
programmatic basis. To the extent there are concerns about indirect impacts on T&E species, they will be
considered in the review for individual sites. Furthermore, the Bureau expects that USFWS will raise any
programmatic impacts on T&E species with the Commission during the Section 7(a)(1) consultation.

Comment 5.14

: Nothing in the PEA recognizes the positive effects of towers on bird well-being:
a) Scores of towers constructed around the United States have no evidence of any bird fatalities.
b) Tower owners frequently find that birds have nested in the towers, which complicates tower
maintenance in a number of respects.
c) Any assessment of the effects of towers on birds must take into account both the positive and negative
effects of hindering or delaying tower construction.

Response 5.14

:
a) Many individual towers do not result in bird kills. However, the court directed the FCC to consider
the effects of the entire ASR program, which approves thousands of applications across the United
States every year. Nationwide, avian mortality from communications towers is estimated at 6.6
million birds every year.
b) Eagles nesting in towers can have both a positive effect (the tower provides a nesting site) and a
negative effect (restrictions on servicing and maintenance of tower; for guyed towers, eagles can be
injured or killed by collision with guy wires).
c) The PEA considers the effects of hindering or delaying tower construction in Section 5.4.6,
Economics.

Comment 5.15

: In WC Docket 11-59, the Commission is currently striving to find ways of accelerating
tower construction in view of the increasingly urgent need for more towers. A mistake in this PEA in an
over-exuberant effort to protect birds could completely undercut the objectives and initiatives being
considered in that docket. The FCC should not adopt rules to protect migratory birds without evaluating
the impact those rules will have on other important policy objectives. The Commission should ensure any
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Comments on Draft PEA
new rules do not impede initiatives to deploy wireless broadband services. In a Broadband Siting NOI
adopted earlier this year, the FCC is considering actions it can take to expand the reach and reduce the
costs of broadband deployment by improving government policies for access to rights-of-way and
wireless facilities siting. The record details a number of delays and obstacles associated with USFWS
reviews of towers for impacts on T&E species, critical habitats, and migratory birds. These delays and
obstacles are likely to increase if the FCC imposes new rules to protect migratory birds; the FCC should
work with USFWS to reduce these delays and standardize reviews.

Response 5.15

: NEPA requires a Federal agency to consider all aspects of the human environment and to
balance consideration of the various impacts an action may cause. The PEA addresses impacts on
deployment under Section 5.4.6, Economics. Also, if an action will have environmental impacts that are
significant, balancing those impacts against programmatic goals must occur in an EIS. In a rulemaking
implementing the findings of the PEA, the Commission will consider how any such rules would affect
broadband deployment and other FCC objectives. If the Commission determines in a rulemaking that the
overriding interest in deployment requires selection of an option that does not support a FONSI, it will
commence an EIS in which it will perform the requisite balancing.
9.2.6 Chapter 6 – Cumulative Impacts

Comment 6.1

: The FCC analysis of cumulative impacts should address the relative vulnerability of
migratory birds based on abundance, status, and population trends. It is scientifically meaningless to
evaluate impacts to migratory birds as a whole or to express mortality from towers as a proportion of all
bird mortality. This approach is flawed because it lumps all birds together without regard for their status
as rare or common. The use of aggregate bird data, as opposed to species level data, is the most
fundamental flaw of the PEA.

Response 6.1

: As is the case with direct impacts, there is insufficient species-specific data available to
break out tower mortality impacts on individual populations, and the Bureau is not required to obtain
information that is essentially unobtainable due to exorbitant costs or the lack of means to obtain the
information. See Response 5.3 above. Species listed as threatened or endangered under the ESA are
protected under existing FCC rules and impacts to those species are addressed in Section 5.4.3.2.

Comment 6.2

: The cumulative impacts analysis does not address impacts on federally listed migratory
bird species and migratory BCC species, both of which have been granted greater protections than other
birds and must be separately evaluated, making the cumulative impacts analysis fatally flawed.

Response 6.2

: See Response 5.1.a above.

Comment 6.3

: The cumulative impacts analysis is flawed. Case law supports a finding that an
incremental increase in adverse impact to a resource can be significant.

Response 6.3

: While an incremental increase in impact on an already stressed environmental resource
could be significant, an evaluation of cumulative significance ultimately depends on all the facts. In this
instance, the incremental impact of registered towers on migratory birds is small relative to the impact of
all other actions. Furthermore, this impact occurs against a backdrop of high natural mortality to birds
during migration. Taking these considerations together, the impact of towers on migratory birds is not
cumulatively significant nationally.

Comment 6.4

: The PEA acknowledges climate change, but does not analyze it. There is no question that
changes in migration patterns are in response to climate change.

Response 6.4

: The PEA presents a brief description of how climate change affects migratory birds by
causing a shift in winter bird ranges to the north and changes in habitats. These are indirect effects that
may contribute in some way to migratory bird mortality, but no data are available to be able to address
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Comments on Draft PEA
specific effects of climate change on migratory birds. There may be additional effects such as changes
and shifts in prey organisms and predator populations.
9.2.7 Chapter 7 - Findings

Comment 7.1

: The PEA ignores the advice of USFWS migratory bird experts and other leading experts
in the field.

Response 7.1

: The Bureau reviewed the available evidence in reaching its conclusions. The term
“significance” for purposes of NEPA is not a scientific term but a legal one, so USFWS’s expertise
informs the evaluation of impacts but is not conclusive.
9.2.8 Chapter 8 – Mitigation

Comment 8.1

: The FCC should adopt through the NEPA process updates to the USFWS voluntary
communications tower guidelines when such updates become available.

Response 8.1

: Many elements of the guidelines are incorporated into the alternatives considered and the
mitigation measures recommended in Chapter 8. However, because of the wording of the guidelines, e.g.,
“to the extent possible,” the guidelines do not easily lend themselves to adoption as a set of criteria. Any
adoption of any guidelines provisions as requirements would occur through a rulemaking process, not
through the PEA.

Comment 8.2

: The PEA should include a consistent and comprehensive monitoring strategy and the final
document should include monitoring and mitigation measures.

Response 8.2

: Section 8.4 of the PEA has been revised to clarify that tower owners and applicants are
encouraged to support monitoring among other forms of research. The FCC already requires monitoring
of individual towers in appropriate circumstances where there are specific concerns about their effects on
migratory birds.
9.2.9 Chapter 11 – References

Comment 11.1

: The PEA cites and does not disclaim many conference proceedings and unpublished
works other than Longcore et al. (2011a and 2011b, both in preparation [cited in final PEA as Longcore et
al. 2012 in press and Longcore et al. 2011 in preparation, respectively]) that are not published in the peer-
reviewed academic literature, and in fact relies upon their conclusions. The draft PEA references 41
sources that are not published in peer-reviewed academic sources.

Response 11.1

: An EA should include all reference sources reviewed or used in its preparation,
regardless of whether the sources were used to help develop its conclusions. Not all sources listed in the
references section of the PEA are accorded the same weight. The non-published sources cited in the PEA
include government regulations, public notices, agency websites, agency technical reports, and others,
which are commonly included as references used in an EA.
The PEA does not rely upon any single source or group of sources, published or unpublished, to develop
conclusions. Many different sources were reviewed and their information used to help develop the
information presented in the PEA. The Federal agency has the responsibility to make determinations
regarding the conclusions reached in its NEPA document. The Bureau relied upon the expertise of
professional biologists, scientists, CEQ, and NEPA specialists, as well as USFWS and academic/private
researchers, to assist it in developing the conclusions presented.
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List of Preparers

SECTION TEN

LIST OF PREPARERS

URS Preparers
Jeffrey Reidenauer, PhD, Project Manager
Angela Chaisson, CWB, Principal Ecologist
Richard Podolsky, PhD, Principal Ornithologist
Kathy Baumgaertner, Principal NEPA Specialist
Katie Eberhart, Senior Ornithologist
Suzanne Richert, Senior NEPA Specialist
Amy Siegel, Document Control Supervisor
Susan Patton, Senior Technical Editor
Young Cho, Senior Word Processor
FCC Reviewers
Jane Jackson, Wireless Telecommunications Bureau
Jeffrey Steinberg, Wireless Telecommunications Bureau
Aaron Goldschmidt, Wireless Telecommunications Bureau
Stephen DelSordo, Federal Preservation Officer, Wireless Telecommunications Bureau
Diane Dupert, Wireless Telecommunications Bureau
Michael Wagner, Media Bureau
Adrienne Denysyk, Media Bureau
John Adams, Public Safety and Homeland Security Bureau
David Ward, Public Safety and Homeland Security Bureau
Robert Weller, Office of Engineering and Technology
Ed Mantiply, Office of Engineering and Technology
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11-13

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Appendix A
Agencies, Organizations, and Individuals Consulted During the NEPA Process

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Appendix A
Agencies, Organizations, and Individuals Consulted During the NEPA Process

Agencies

Ellen M. Athas, Senior Counsel, Council on Environmental Quality
Marcia L. Pradines, Acting Chief, USFWS Division of Migratory Bird Management
Albert M. Manville, II, Ph.D., Senior Wildlife Biologist, USFWS Division of Migratory Bird
Management
Nanette W.H. Seto, Wildlife Biologist, USFWS Division of Migratory Bird Management
Diana M. Whittington, Wildlife Biologist, USFWS Division of Migratory Bird Management
Richard E. Sayers, Jr., Ph.D., Chief, USFWS Division of Consultation, HCPs, Recovery and State Grants
John J. Fay, Ph.D., Biologist, USFWS Division of Consultation, HCPs, Recovery and State Grants

Organizations

CTIA – The Wireless Association
National Association of Broadcasters
National Association of Tower Erectors
PCIA – The Wireless Infrastructure Association
American Bird Conservancy, Inc. (ABC)
Defenders of Wildlife
National Audubon Society

Individuals

Travis Longcore, Ph.D., The Urban Wildlands Group
Joelle Gehring, Ph.D., Michigan State University
A-1

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Appendix B
Avian/Tower Collision Literature Summary

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Appendix B
Avian/Tower Collision Literature Summary

AVIAN MORTALITY SUMMARY

Tower Height

Number of

Number of

Guyed

Total Number of

AGL

State

Lighting Type

Years

Bird Fatalities

Source

(Yes/No)

Sampling Days

feet (meters)

Sampled

Reported

100 (30.5)
Kansas
Yes
1
0
Young et al. (2000)
<150 (46)
Pennsylvania
147 - >1,000
Manville (per. comm.) –
unpublished data
197 (60)
Tennessee
Yes
None
215
3.5
14
Nicholson et al. (2005)***
197 (60)
Wisconsin
180
2
3
Travis (2009)
197 (60)
Wisconsin
180
2
1
Travis (2009)
259 (79)
Wisconsin
180
2
8
Travis (2009)
295 (90)
Florida
Yes
1.5
14
Crawford and Engstrom
(1999)
361 (110)
Wisconsin
180
2
6
Travis (2009)
358 (109)
Wisconsin
180
2
7
Travis (2009)
361 (110)
Wisconsin
180
2
3
Travis (2009)
380-479
Michigan
No
White strobe (L-865)
40
1
5
Gehring et al. (2009)
(116–146)*
380-479
Michigan
No
Red strobe (L-864)
40
1
5
Gehring et al. (2009)
(116–146)*
380-479
Michigan
No
Red flashing
40
1
6
Gehring et al. (2009)
(116–146)*
incandescent (L-864)
380-479
Michigan
Yes
White strobe (L-865)
40
1
11
Gehring et al. (2009)
(116–146)*
380-479
Michigan
Yes
Red strobe (L-864)
40
1
20
Gehring et al. (2009)
(116–146)*
380-479
Michigan
Yes
Red flashing
40
1
22
Gehring et al. (2009)
(116–146)*
incandescent (L-864)
380-479
Michigan
Yes
Steady-burning, red lights
40
1
55
Gehring et al. (2009)
(116–146)*
(L-864 and L-810)
380-479
Michigan
No
Flashing and steady-
60
2
17
Gehring et al. (2009)
(116–146)*
burning red lights (L-864
and L-810)
B-1

Appendix B
Avian/Tower Collision Literature Summary

AVIAN MORTALITY SUMMARY

Tower Height

Number of

Number of

Guyed

Total Number of

AGL

State

Lighting Type

Years

Bird Fatalities

Source

(Yes/No)

Sampling Days

feet (meters)

Sampled

Reported

380-479
Michigan
Yes
Flashing and steady
60
2
194
Gehring et al. (2009)
(116–146)*
burning red lights (L-864
and L-810)
380-479
Michigan
No
Flashing and steady
60
1.5
14
Gehring et al.
(116–146)*
burning red lights (L-864
and L-810)
380-479
Michigan
Yes
Flashing and steady-
100
2.5
249
Gehring et al.
(116–146)*
burning red lights (L-864
and L-810)
436 (133)
New
Yes
2
134
Sawyer (1961)
Hampshire
466 (142)
Wisconsin
180
2
14
Travis (2009)
466 (142)
Wisconsin
180
2
5
Travis (2009)
528 (161)
West Virginia
Yes
6
116
Herron (1997)
535 (163)
Wisconsin
180
2
20
Travis (2009)
605-1588
Illinois
Yes
13
0.5
5,465
Seets and Bohlen (1977)
(184.4 – 484)**
627 (191)
Florida
Yes
Red and white lights 1
1
617
Roberts and Tamborski
(1993)
942 (287)
Tennessee
Yes
19.75
253
Laskey (1960,1962,
1963a,b, 1964, 1967, 1968,
1969a,b, 1971),
Goodpasture (1974a, b,
1975, 1976, 1984, 1986);
Bierly (1973)
961 (293)
New York
Yes
Red beacon
4-33
30
267
Morris et al. (2003)
981 (299)
Iowa
Yes
2
243
Brewer and Ellis (1958)
984 (300)
Michigan
Yes
4.5
44
Caldwell and Wallace
(1966)
B-2

Appendix B
Avian/Tower Collision Literature Summary

AVIAN MORTALITY SUMMARY

Tower Height

Number of

Number of

Guyed

Total Number of

AGL

State

Lighting Type

Years

Bird Fatalities

Source

(Yes/No)

Sampling Days

feet (meters)

Sampled

Reported

1000
Michigan
Yes
Flashing and steady-
40
1
256
Gehring et al. (2009)
(>305)*
burning red lights (L-864
and L-810)
1000
Michigan
Yes
Flashing and steady-
40
1
164
Gehring et al. (2009)
(>305)*
burning red lights (L-864
and L-810)
1000
Michigan
Yes
Flashing and steady-
80
2.5
416
Gehring et al.
(>305)*
burning red lights (L-864
and L-810)
1001 (305)
Wisconsin
Yes
38
3,198
Kemper (1996)
1011 (308)
Florida
Yes
13
618
Crawford and Engstrom
(2001)
1059 (323)
New York
Yes
Red beacon
30
35
Morris et al. (2003)
1076 (328)
New York
Yes
Red beacon
30
370
Morris et al. (2003)
1084 (330)
Ohio
Yes
Red beacon
19
227
Morris et al. (2003)
1089 (332)
South Dakota
Yes
1
1
>3,750
Manville (pers comm 2011)
1122 (342)
Michigan
Yes
5.25
330
Caldwell and Wallace
(1966)
1188 (362)
North Carolina
Yes
2
498
Carter and Parnell (1976,
1978)
1201 (366)
North Dakota
Yes
2
282
Avery and Clement (1972);
Avery et al. (1977)
1201 (366)
Kansas
Yes
1.5
83
Boso (1965)
1280 (390)
Michigan
Yes
5.25
757
Caldwell and Wallace
(1966)
1299 (396)
Wisconsin
180
2
760
Travis (2009)
1312 (400)
Minnesota
Yes
5
701
Strnad (1962, 1975)
1348 (411)
Massachusetts
Yes
1.5
338
Baird (1970, 1971)
1368 (417)
Tennessee
Yes
29.75
689
Nehring and Bivens (1999)
B-3

Appendix B
Avian/Tower Collision Literature Summary

AVIAN MORTALITY SUMMARY

Tower Height

Number of

Number of

Guyed

Total Number of

AGL

State

Lighting Type

Years

Bird Fatalities

Source

(Yes/No)

Sampling Days

feet (meters)

Sampled

Reported

1369 (417)
Tennessee
Yes
Red steady and flashing
6
1
336
Ganier (1962)
1424 (434)
Wisconsin
180
2
237
Travis (2009)
1440 (439)
Kansas
Yes
2
471
Young and Robbins (2001)
1483 (452)
Florida
Yes
3
3,043
Taylor and Anderson
(1973, 1974)
1995 (608)
North Carolina
Yes
2
1,111
Carter and Parnell (1976,
1978)
2001 (610)
Iowa
Yes
1.75
2,012
Mosman (1975)
B-4

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