[Federal Register Volume 88, Number 82 (Friday, April 28, 2023)]
[Proposed Rules]
[Pages 26432-26466]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-08719]



[[Page 26431]]

Vol. 88

Friday,

No. 82

April 28, 2023

Part III





Department of Commerce





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National Oceanic and Atmospheric Administration





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50 CFR Part 217





Taking and Importing Marine Mammals; Taking Marine Mammals Incidental 
to the U.S. Coast Guard's Alaska Facility Maintenance and Repair 
Activities; Proposed Rule

  Federal Register / Vol. 88 , No. 82 / Friday, April 28, 2023 / 
Proposed Rules  

[[Page 26432]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 230420-0108]
RIN 0648-BK57


Taking and Importing Marine Mammals; Taking Marine Mammals 
Incidental to the U.S. Coast Guard's Alaska Facility Maintenance and 
Repair Activities

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Coast Guard (Coast 
Guard) for authorization to take marine mammals incidental to 
conducting construction activities related to maintenance and repair at 
facilities in Alaska over the course of 5 years (2023-2028). As 
required by the Marine Mammal Protection Act (MMPA), NMFS is proposing 
regulations to govern that take, and requests comments on the proposed 
regulations.

DATES: Comments and information must be received no later than May 30, 
2023.

ADDRESSES: Submit all electronic public comments via the Federal e-
Rulemaking Portal. Go to www.regulations.gov and enter NOAA-NMFS-2022-
0023 in the Search box. Click on the ``Comment'' icon, complete the 
required fields, and enter or attach your comments.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. All comments received are a part of the 
public record and will generally be posted for public viewing on 
www.regulations.gov without change. All personal identifying 
information (e.g., name, address), confidential business information, 
or otherwise sensitive information submitted voluntarily by the sender 
will be publicly accessible. NMFS will accept anonymous comments (enter 
``N/A'' in the required fields if you wish to remain anonymous). 
Attachments to electronic comments will be accepted in Microsoft Word, 
Excel, or Adobe PDF file formats only.

FOR FURTHER INFORMATION CONTACT: Cara Hotchkin, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION: 

Availability

    A copy of the Coast Guard's application and any supporting 
documents, as well as a list of the references cited in this document, 
may be obtained online at: www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. In case of problems accessing these documents, please call 
the contact listed above (see FOR FURTHER INFORMATION CONTACT).

Purpose and Need for Regulatory Action

    We received an application from Coast Guard requesting 5-year 
regulations and authorization to take multiple species of marine 
mammals. This proposed rule would establish a framework under the 
authority of the MMPA (16 U.S.C. 1361 et seq.) to allow for the 
authorization of take of marine mammals incidental to the Coast Guard's 
construction activities related to maintenance and repair at facilities 
in Alaska.

Legal Authority for the Proposed Action

    Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1371(a)(5)(A)) directs 
the Secretary of Commerce to allow, upon request, the incidental, but 
not intentional taking of small numbers of marine mammals by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) within a specified geographical region for up to five years 
if, after notice and public comment, the agency makes certain findings 
and issues regulations that set forth permissible methods of taking 
pursuant to that activity and other means of effecting the ``least 
practicable adverse impact'' on the affected species or stocks and 
their habitat (see the discussion below in the Proposed Mitigation 
section), as well as monitoring and reporting requirements. Section 
101(a)(5)(A) of the MMPA and the implementing regulations at 50 CFR 
part 216, subpart I provide the legal basis for issuing this proposed 
rule containing 5-year regulations, and for any subsequent Letters of 
Authorization (LOAs). As directed by this legal authority, this 
proposed rule contains mitigation, monitoring, and reporting 
requirements.

Summary of Major Provisions Within the Proposed Rule

    Following is a summary of the major provisions of this proposed 
rule regarding Coast Guard construction activities. These measures 
include:
     Required monitoring of the construction areas to detect 
the presence of marine mammals before beginning construction 
activities.
     Shutdown of construction activities under certain 
circumstances to avoid injury of marine mammals.
     Soft start for impact pile driving to allow marine mammals 
the opportunity to leave the area prior to beginning impact pile 
driving at full power.

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are issued or, if the taking is limited to harassment, a notice of a 
proposed incidental take authorization may be provided to the public 
for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to as ``mitigation''); 
and requirements pertaining to the mitigation, monitoring, and 
reporting of the takings are set forth. The definitions of all 
applicable MMPA statutory terms cited above are included in the 
relevant sections below.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must evaluate our proposed action (i.e., the promulgation of 
regulations and subsequent issuance of incidental take authorization) 
and alternatives with respect to potential impacts on the human 
environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 of the Companion Manual for NAO 216-6A, 
which do not individually or

[[Page 26433]]

cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has preliminarily determined that the 
proposed action qualifies to be categorically excluded from further 
NEPA review.
    Information in the Coast Guard's application and this document 
collectively provide the environmental information related to proposed 
issuance of these regulations and subsequent incidental take 
authorization for public review and comment. We will review all 
comments submitted in response to this document prior to concluding our 
NEPA process or making a final decision on the request for incidental 
take authorization.

Summary of Request

    On March 15, 2021, NMFS received an application from the Coast 
Guard requesting authorization for take of marine mammals incidental to 
construction activities related to maintenance and repair at eight 
Coast Guard facilities in Alaska. On November 24, 2021 (86 FR 67023), 
we published a notice of receipt of the Coast Guard's application in 
the Federal Register, requesting comments and information related to 
the request for 30 days. We received no public comments. After the 
applicant responded to our questions and redrafted the application, we 
determined the application was adequate and complete on January 19, 
2022. On August 12, 2022, the Coast Guard submitted a minor 
modification to their application (to include vibratory driving of 
composite piles as part of the specified activity).
    The Coast Guard proposes to conduct construction necessary for 
maintenance and repair of existing in-water structures at the following 
eight Coast Guard station facilities in Alaska: Kodiak, Sitka, 
Ketchikan, Valdez, Cordova, Juneau, Petersburg, and Seward. These 
repairs would include installation and removal of steel, concrete, and 
timber piles, involving use of impact and vibratory hammers and Down-
The-Hole drilling (DTH) equipment, and removal of piles by cutting, 
clipping, or vibration. Maintenance activities may also include 
underwater power washing. Up to 245 piles will be removed and replaced 
on a 1 to 1 basis (i.e., total pile numbers at these facilities are 
expected to remain the same) over the 5-year period of effectiveness 
for the regulations. Hereafter (unless otherwise specified or detailed) 
we use the term ``pile driving'' to refer to both pile installation and 
pile removal. The use of vibratory, DTH, and impact pile driving 
equipment expected to produce underwater sound at levels that have the 
potential to result in harassment of marine mammals.
    The Coast Guard requests authorization to take individuals of 14 
species by Level B harassment and, for an additional 3 species (harbor 
seal, harbor porpoise, and Dall's porpoise), by Level A harassment. The 
proposed regulations would be valid for 5 years (2023-2028).

Description of the Specified Activity

Overview

    Maintaining existing wharfs and piers is vital to sustaining the 
Coast Guard's mission and ensuring readiness. To ensure continuance of 
necessary missions at the eight facilities, the Coast Guard must 
conduct annual maintenance and repair activities at existing marine 
waterfront structures, including removal and replacement or repair of 
piles of various types and sizes. Exact timing and amount of necessary 
in-water work is unknown, but the Coast Guard estimates replacing up to 
245 structurally unsound piles over the 5-year period, including 
individual actions currently planned and estimates for future marine 
structure repairs. Construction will include use of impact, DTH, and 
vibratory pile driving, including removal and installation of steel, 
concrete, composite, and timber piles. Pile removal may occur by 
various cutting or clipping methods and power washing may occur on some 
piles being repaired. Pile cutting, clipping, and power washing, and 
certain other activities (e.g., deck repair, moving of rip-rap, etc.) 
are not anticipated to have the potential to result in incidental take 
of marine mammals because they are either above water, do not last for 
sufficient duration to present the reasonable potential for disruption 
of behavioral patterns, do not produce sound levels with likely 
potential to result in marine mammal harassment, or some combination of 
the above.
    The Coast Guard's inspection program prioritizes deficiencies in 
marine structures and plans those maintenance and repairs for design 
and construction. The Coast Guard's proposed activities include 
individual projects (where an existing need has been identified) and 
estimates for ongoing repairs. Estimates of activity levels for ongoing 
repairs are based on Coast Guard surveys of existing structures, which 
provide assessments of structure condition and estimates of numbers of 
particular pile types that may require replacement (at an assumed 1:1 
ratio) over the 5-year duration of these proposed regulations. 
Additional allowance is made for the likelihood that future waterfront 
inspections will reveal unexpected damage, or that damage caused by 
severe weather events and/or incidents caused by vessels will result in 
need for additional contingency repairs. This regional programmatic 
approach to MMPA compliance is expected to allow for efficient 
compliance for the Coast Guard, while satisfying the requirements of 
the MMPA. The detailed discussion of planned or anticipated projects 
provided here and in the Coast Guard's application allow for more 
comprehensive analysis, while providing a reduction in the time and 
effort that could be required to obtain individual incidental take 
authorizations. LOAs could be issued for projects conducted at any or 
all of the eight facilities if they fit within the structure of the 
programmatic analysis provided herein and are able to meet the 
requirements described in the regulations.
    The Coast Guard would report to NMFS on an annual basis prior to 
the start of in-water work windows to review results of relevant 
projects conducted in the preceding in-water work window and propose 
upcoming projects. The intent is to utilize lessons learned to better 
inform potential effects of future activities through adaptive 
management.

Dates and Duration

    The proposed regulations would be valid for a period of 5 years 
from the date of issuance. The specified activities may occur at any 
time during the 5-year period of validity of the proposed regulations, 
subject to existing timing restrictions. These timing restrictions, or 
in-water work windows, are designed to protect fish species listed 
under the Endangered Species Act (ESA) as well as marine mammals under 
the MMPA. No work would occur outside these work windows unless 
necessary for the safety and stability of the structure. Work windows 
for the eight facilities are described in Table 1. Pile driving could 
occur on any day within in-water work windows during the period of 
validity of these proposed regulations.

[[Page 26434]]



            Table 1--In-Water Work Windows for Each Facility
------------------------------------------------------------------------
                                 Period of no in-
           Facility                 water work             Notes
------------------------------------------------------------------------
Kodiak........................  May 1-June 30....  pink salmon fry and
                                                    coho salmon smolts.
Sitka.........................  March 1-October 1  herring spawning and
                                                    summer prey feeding.
Ketchikan.....................  April 1-June 30..  outmigrating juvenile
                                                    salmon.
Valdez........................  March 1-October 1  herring spawning and
                                                    summer prey feeding,
                                                    whale presence,
                                                    Steller sea lion
                                                    breeding.
Cordova.......................  March 1-October 1  herring spawning and
                                                    summer prey feeding,
                                                    whale presence,
                                                    Steller sea lion
                                                    breeding.
Juneau........................  May 1-June 30....  pink and chum salmon
                                                    fry and coho and
                                                    Chinook salmon
                                                    smolt, hatchery net
                                                    pen species.
Petersburg....................  April 1-June 30..  outmigrating juvenile
                                                    salmon.
Seward........................  May 1-June 30....  pink salmon fry and
                                                    coho salmon smolts.
------------------------------------------------------------------------

    For many projects the design details are not known in advance; 
thus, it is not possible to state the exact number of pile driving days 
that will be required. Days of pile driving at each site were based on 
the estimated work days using a slow production rate, i.e., one pile 
removed per day and one pile installed per day. These conservative 
rates give the following estimates of total days at each facility over 
the 5-year duration: Kodiak: 100 days, Sitka: 50 days, Ketchikan: 100 
days, Valdez: 15 days, Cordova: 6 days, Juneau: 100 days, Petersburg: 
20 days, and Seward: 4 days. These totals include both removal and 
installation of piles, and represent a conservative estimate of pile 
driving days at each facility. In a real construction situation, pile 
driving production rates would be maximized when possible and actual 
daily production rates may be higher, resulting in fewer actual pile 
driving days.

Specified Geographical Region

    The eight facilities are located within the coastal waters of the 
Gulf of Alaska (Figure 1). For full details regarding the facilities 
and specified geographical region, please see sections 1.3 and 2, 
respectively, of the Coast Guard's application.
[GRAPHIC] [TIFF OMITTED] TP28AP23.001

Figure 1--Location of the Eight Facilities

    Coast Guard Base Kodiak is located on Womens Bay, a largely 
enclosed arm of the larger Chiniak Bay on the northeast side of Kodiak 
Island, Alaska's largest island. Womens Bay is separated from the rest 
of Chiniak Bay by Nyman Peninsula providing a protected harbor for 
Coast Guard vessels. Coast Guard vessels are the primary users of 
Womens Bay; however, a sea plane runway is present at the mouth of the 
bay and barges regularly transit Womens Bay.

[[Page 26435]]

Two of the three piers (the Fuel Pier and Cargo Wharf) at Base Kodiak 
need periodic maintenance and repair, while the Marginal Wharf is 
currently being evaluated for demolition. Any actions related to the 
Marginal Wharf would occur under a separate action. Because there is 
the potential for contaminated sediments at this location, no pressure 
washing will occur.
    The Coast Guard's Sitka Moorings are located near Sitka Harbor on 
the Sitka Channel separating Japonski Island from the larger Baranof 
Island. The Sitka Channel connects the Eastern Anchorage southeast of 
Sitka to the Western Anchorage northwest of the town. Beyond Coast 
Guard vessels, typical vessel traffic within the Sitka Channel includes 
private watercraft, commercial fishing vessels, and seaplanes.
    Base Ketchikan is situated on Revillagigedo Island, which is 
separated from nearby Pennock Island by the East Channel of the Tongass 
Narrows. At Base Ketchikan, the Tongass Narrows are approximately 2,000 
ft (610 meters (m)) across with steep surface bathymetry reaching a 
maximum mid-channel depth of over 100 ft (30 m). The Tongass Narrows 
are a busy passage frequented by private and commercial vehicles, 
including large cruise ships servicing the cruise terminal in Ketchikan 
(north of Base Ketchikan).
    The Coast Guard's Valdez moorings are located west of the entrance 
to Valdez Harbor located on Port Valdez, itself part of the Valdez Arm 
of Prince William Sound. Port Valdez is the U.S.' northernmost ice-free 
port and non-Coast Guard vessel traffic in the immediate vicinity of 
the Valdez moorings includes private craft and commercial cargo 
vessels. The Valdez Marine Terminal is located 2.3 miles (3.7 
kilometers (km)) south of the Valdez moorings and is the offshoring 
point for petroleum products transported via the Trans-Alaska Pipeline, 
with corresponding oil tanker traffic through the area. Depths adjacent 
to the Valdez moorings fall off steeply from approximately 13 ft (4 m) 
at the entrance to Valdez Harbor to over 600 ft (183 m) along the 
centerline of the Valdez Arm.
    The dock used by the Coast Guard at Cordova is owned by the City of 
Cordova and is located on the Cordova waterfront on Orca Inlet, which 
separates the mainland from Hawkins Island. Orca Inlet is generally 
shallow reaching depths of 75 ft (23 m) at the deepest parts of the 
channel with significantly more shallow depths closer to Hawkins and 
Observation Islands.
    The Coast Guard wharf at Station Juneau is on the southeast facing 
portion of the Juneau waterfront on the Gastineau Channel separating 
the North American mainland (Juneau) from Douglas Island. The Gastineau 
Channel is accessible to large vessels up to the bridge linking Douglas 
Island to the mainland and navigable by smaller vessels for its entire 
length. The Channel is generally shallow in the northern section but up 
to 35 ft (10.7 m) deep adjacent to the wharf frontage and up to 100 ft 
(30 m) in the mid-channel south of Station Juneau.
    The Coast Guard moorings in Petersburg are located within 
Petersburg Harbor, which supports the area's commercial fishing 
industry. Petersburg is located at the northern end of the Wrangell 
Narrows separating Mitkof and Kupreanof Islands near the confluence 
with the Frederick Sound. The Narrows are generally only used by 
fishing boats and Alaska Marine Highway ferries as it is too shallow 
and narrow for use by larger vessels. Depths adjacent to the Petersburg 
Moorings are approximately 20 ft (6 m).
    The dock used by the Coast Guard in Seward is owned by the City of 
Seward and is located within Seward Harbor. The Seward Harbor 
breakwaters separate the harbor and moorings from the main body of 
Resurrection Bay. Seward Harbor itself serves smaller craft, with 
larger cruise ships and ferries using facilities just east of the 
harbor. Depths within the harbor, including the harbor entrance, range 
between 12 and 15 ft (4-5 m).

Detailed Description of Activities

    As described above, the Coast Guard has requested incidental take 
regulations for its maintenance and repair program, which includes 
maintenance and repair activities at marine waterfront structures at 
eight facilities within the Gulf of Alaska. In order to address 
identified deficiencies in existing marine structures at the 8 
facilities, the Coast Guard proposes to replace up to 245 structurally 
unsound piles over the 5-year period using methods including impact and 
vibratory pile driving, and DTH to make holes. Existing marine 
structures at the eight facilities are described in detail in section 
6.8 of the Coast Guard's application and details of pile maintenance 
and repair activity are summarized in Table 2.

                                          Table 2--In-Water Maintenance Activity for Each Coast Guard Facility
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Number and material of pile replacements
            Facility             -----------------------------------------------------------------------------------------------------------------------
                                        Year 1              Year 2              Year 3              Year 4              Year 5           Maximum total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kodiak..........................  20 timber * or      20 timber * or      20 timber * or      20 timber * or      20 timber * or      100.
                                   steel.              steel.              steel.              steel.              steel.
Sitka **........................  Replace 5 piles...  Replace 5 piles...  Replace 5 piles...  Replace 5 piles...  Replace 5 piles...  25 piles replaced.
Ketchikan **....................  Replace 10-15       Replace 10-15       Replace 10-15       Replace 10-15       Replace 10-15       50 piles replaced.
                                   timber * piles.     timber * piles.     timber * piles.     timber * piles.     timber * piles.
Valdez **.......................  Replace 1 timber *  Replace 1 timber *  Replace 1 timber *  Replace 1 timber *  Replace 1 timber *  6 piles replaced.
                                   pile.               pile.               pile.               pile, replace 1     pile.
                                                                                               steel guide pile.
Cordova.........................  ..................  Replace 3 steel     ..................  ..................  ..................  3 piles replaced.
                                                       piles.
Juneau **.......................  Replace 10 timber   Replace 10 timber   Replace 10 timber   Replace 10 timber   Replace 10 timber   50 piles replaced.
                                   * piles.            * piles.            * piles.            * piles.            * piles.
Petersburg **...................  Replace 2 fender    Replace 2 fender    Replace 2 fender    Replace 2 fender    Replace 2 fender    10 fender piles
                                   piles.              piles.              piles.              piles.              piles.              replaced.
Seward..........................  ..................  ..................  Replace 1 steel     ..................  ..................  1 pile replaced.
                                                                           pile.
Total Replaced..................  53................  56................  53................  54................  52................  245 piles
                                                                                                                                       replaced.***
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Timber piles will be preferentially replaced with composite piles where technically possible.
** These facilities will also conduct pile repairs; see text for full description of repair methods.
*** Yearly pile numbers may add up to be larger than the number reported here to allow for flexibility between years. Piles replaced may not exceed
  yearly maximum totals.

    The project includes pile repair, extraction, and installation, all 
of which may be accomplished through a variety of methods. However, 
only extraction and installation using DTH equipment and vibratory and 
impact pile drivers

[[Page 26436]]

are expected to have the potential to result in incidental take of 
marine mammals. Pile repair methods include sleeve or jacket 
replacement, pressure washing, rub strip and ladder replacement, 
wrapping, pile encapsulation, painting, coating, and replacement of 
treated wood decking. These processes do not involve pile driving or 
long durations of other loud sound sources and are not expected to have 
the potential to result in incidental take of marine mammals. Pile 
removal may be accomplished via mechanical methods such as clipping, 
clamshell removal, or direct pull. Noise levels produced through these 
activities are not expected to exceed baseline levels produced by other 
routine activities and operations at the eight facilities, and any 
elevated noise levels produced through these activities are expected to 
produce intermittent (and generally continuous) noise, be of short 
duration, or of low peak values. Therefore, only DTH, vibratory, and 
impact pile driving are carried forward for further analysis.
    Vibratory hammers, which can be used to either install or extract a 
pile, contain a system of counter-rotating eccentric weights powered by 
hydraulic motors, and are designed in such a way that horizontal 
vibrations cancel out, while vertical vibrations are transmitted into 
the pile. The pile driving machine is lifted and positioned over the 
pile by means of an excavator or crane, and is fastened to the pile by 
a clamp and/or bolts. The vibrations produced cause liquefaction of the 
substrate surrounding the pile, enabling the pile to be extracted or 
driven into the ground using the weight of the pile plus the hammer.
    Impact hammers use a rising and falling piston to repeatedly strike 
a pile and drive it into the ground. Steam, hydraulic and pneumatic 
hammers use compressed fluids to create the force to raise or drive a 
piston weight. A diesel hammer works much like a car engine with fuel 
injected into a combustion chamber where the fuel is then ignited and 
the force of the explosion drives a piston, which pushes the pile down 
with great force.
    DTH systems create holes by combining impact forces from a 
hydraulically or pneumatically controlled piston and hammer that 
directly impact the substrate along with a rotating drill function, 
aided by an intricate series of rock cutting bits on the end of the 
hammer.
    Steel piles are typically vibratory-driven for their initial 
embedment depths or to refusal and finished with an impact hammer for 
proofing or until the pile meets structural requirements, as necessary. 
Where structural requirements necessitate stronger support piles may 
need to be driven into bedrock substrates. DTH systems are used for 
this purpose. Proofing involves striking a driven pile with an impact 
hammer to verify that it provides the required load-bearing capacity, 
as indicated by the number of hammer blows per foot of pile 
advancement. Non-steel piles (concrete, timber, composite) are 
typically impact-driven for their entire embedment depth, in part 
because non-steel piles are often displacement piles (as opposed to 
pipe piles) and require some impact to allow substrate penetration. 
Pile installation can range from under one minute to 60 minutes 
depending on pile type, pile size, and conditions (i.e., bedrock, loose 
soils, etc.) to reach the required tip elevation. DTH can typically 
take multiple hours depending on the equipment, rock hardness, and 
required hole depth, though the process is dynamic and driving is not 
continuous.
    The most effective and efficient method of pile driving available 
would be implemented in each case. The method fitting these criteria 
may vary based on specific project requirements and local conditions. 
Impact driving, while generally producing higher levels of sound, also 
minimizes the net amount of active driving time, thus reducing the 
amount of time during which marine mammals may be exposed to noise. 
Impact, DTH, or vibratory pile driving could occur on any day but would 
not occur simultaneously. Location-specific pile totals are given in 
Table 2 and described below. These totals assume a 1:1 replacement 
ratio; however, the actual number installed may result in a replacement 
ratio of less than 1:1.
    Steel, concrete, timber, and composite piles will all be a maximum 
of 24-inch (0.61 m) diameter. For purposes of analysis, it is assumed 
that any unknown pile type would be steel, since this would give a 
worst-case scenario in terms of loudest noise levels produced. All 
concrete, composite, and timber piles are assumed to be installed 
entirely by impact pile driver, and all steel piles are assumed to 
require some use of an impact driver. This is a conservative 
assumption, as all steel piles would be initially driven with a 
vibratory driver until they reach a point of refusal (where substrate 
conditions make use of a vibratory hammer ineffective) or engineering 
specifications require impact driving to verify load-bearing capacity. 
Therefore, some steel piles may not in fact require use of the impact 
driver during installation. DTH will only be used at Ketchikan and 
Kodiak.
    At this time, of the 245 piles expected to be extracted, 5 have 
been identified as steel piles (3 at Cordova, 1 each at Seward and 
Valdez) and 106 as timber piles (50 each at Ketchikan and Juneau, 5 at 
Valdez, and 1 at Seward). The remaining piles have not been identified 
to type and so for analysis will be considered to be steel, typically 
the loudest type. Replacement will often be of the same type, but could 
include different materials, though diameters will generally be the 
same. Replacements for extracted timber piles will typically be 
composite piles of similar diameter.
    Pile driving could occur on any work day within in-water work 
windows during the period of validity of these proposed regulations. 
Proposed mitigation, monitoring, and reporting measures are described 
in detail later in this document (please see Proposed Mitigation and 
Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of the Specified Activity

    We have reviewed the Coast Guard's species descriptions that 
summarize available information regarding status and trends, 
distribution and habitat preferences, behavior and life history, and 
auditory capabilities of the potentially affected species, for accuracy 
and completeness and refer the reader to Sections 3 and 4 of the 
application, instead of reprinting all of the information here. 
Additional information regarding population trends and threats may be 
found in NMFS' Stock Assessment Reports (SAR; www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and 
more general information about these species (e.g., physical and 
behavioral descriptions) may be found on NMFS' website 
(www.fisheries.noaa.gov/find-species).
    Table 3 lists all species or stocks for which take is expected and 
proposed to be authorized for this action and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and ESA and potential biological removal (PBR), where known. 
PBR, defined by the MMPA as the maximum number of animals, not 
including natural mortalities, that may be removed from a marine mammal 
stock while allowing that stock to reach or maintain its optimum 
sustainable population, is considered in concert with known sources of 
ongoing anthropogenic mortality (as described in NMFS' SARs).

[[Page 26437]]

While no mortality is anticipated or authorized here, PBR and annual 
serious injury and mortality from anthropogenic sources are included 
here as gross indicators of the status of the species and other 
threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS' stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in the specified geographical 
regions are assessed in either NMFS' U.S. Alaska SARs or U.S. Pacific 
SARs. All values presented in Table 3 are the most recent available at 
the time of writing and are available in the draft 2022 SARs (available 
online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-species-stock).

                                              Table 3--Species Likely Impacted by the Specified Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/ MMPA status;   Stock abundance (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
    Gray whale......................  Eschrichtius robustus..  Eastern North Pacific..  -, -, N             26,960 (0.05, 25,849,         801        131
                                                                                                             2016).
Family Balaenopteridae (rorquals):
    Humpback whale..................  Megaptera novaeangliae.  Central North Pacific..  -, -, Y             10,103 (0.30, 7,891,           83         26
                                                                                                             2006).
                                                               Western North Pacific..  E, D, Y             1,107, (0.30, 865,              3        2.8
                                                                                                             2006).
    Fin whale.......................  Balaenoptera physalus..  Northeast Pacific......  E, D, Y             UND (UND, UND, 2013)..        UND        0.6
    Minke whale.....................  Balaenoptera             Alaska.................  -, -, N             N/A (N/A, N/A, N/A)           UND          0
                                       acutorostrata.                                                        \4\.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Killer whale....................  Orcinus orca...........  Eastern North Pacific    -, -, N             1,920 (N/A, 1,920,             19        1.3
                                                                Alaska Resident.                             2009).
                                                               Eastern North Pacific    -, -, N             587 (N/A, 587, 2012)..        5.9        0.8
                                                                Gulf of Alaska,
                                                                Aleutian Islands,
                                                                Bearing Sea Transient.
                                                               Eastern North Pacific    -, -, N             302 (N/A, 302, 2018)..        2.2        0.2
                                                                Northern Resident.
                                                               AT1 Transient..........  -, D, Y             7 (N/A, 7, 2019)......        0.1          0
                                                               West Coast Transient...  -, -, N             349 (N/A, 349, 2018)..        3.5        0.4
    Pacific white-sided dolphin.....  Lagenorhynchus           North Pacific..........  -, -, N             26,880 (UND, UND,             UND          0
                                       obliquidens.                                                          1990).
Family Phocoenidae (porpoises):
    Dall's porpoise \5\.............  Phocoenoides dalli.....  Alaska.................  -, -, N             UND (UND, UND, 2015)..        UND         37
    Harbor porpoise \6\.............  Phocoena phocoena......  Southeast Alaska.......  -, -, Y             1,302 (0.21, 1,057,            11         34
                                                                                                             2019).
                                                               Gulf of Alaska.........  -, -, Y             31,046 (0.21, N/A,            UND         72
                                                                                                             1998).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    California sea lion.............  Zalophus californianus.  U.S....................  -, -, N             257,606 (N/A, 233,515,     14,011       >321
                                                                                                             2014).
    Northern fur seal...............  Callorhinus ursinus....  Eastern Pacific........  -, D, Y             626,618 (0.2, 530,376,     11,403        373
                                                                                                             2019).
    Steller sea lion................  Eumetopias jubatus.....  Eastern................  -,-, N              43,201 (N/A, 43,201,        2,592        112
                                                                                                             2017).
                                      Eumetopias jubatus.....  Western................  E, D, Y             52,932 (N/A, 52,932,          318        254
                                                                                                             2019).
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Prince William Sound...  -, -, N             44,756 (N/A, 41,776,        1,253        413
                                                                                                             2015).
                                                               Lynn Canal/Stephens      -, -, N             13,388 (N/A, 11,867,          214         50
                                                                Passage.                                     2016).
                                                               Sitka/Chatham Straight.  -, -, N             13,289 (N/A, 11,883,          356         77
                                                                                                             2015).
                                                               Clarence Strait........  -, -, N             27,659 (N/A, 24,854,          746         40
                                                                                                             2015).
                                                               South Kodiak...........  -, -, N             26,448 (N/A, 22,351,          939        127
                                                                                                             2017).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
  designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or
  which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is
  automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments/ assessments/. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable (N/A). UND
  indicates data unavailable.
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury (M/SI) from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ No population estimates have been made for the number of minke whales in the entire North Pacific. Some information is available on the numbers of
  minke whales in some areas of Alaska, but in the 2009, 2013, and 2015 offshore surveys, so few minke whales were seen during the surveys that a
  population estimate for the species in this area could not be determined (Rone et al., 2017). Therefore, this information is N/A (not available).
\5\ Previous abundance estimates covering the entire stock's range are no longer considered reliable and the current estimates presented in the SARs and
  reported here only cover a portion of the stock's range. Therefore, the calculated Nmin and PBR is based on the 2015 survey of only a small portion of
  the stock's range. PBR is considered to be biased low since it is based on the whole stock whereas the estimate of mortality and serious injury is for
  the entire stock's range.
\6\ Abundance estimates assumed that detection probability on the trackline was perfect; work is underway on a corrected estimate. Additionally,
  preliminary data results based on environmental DNA analysis show genetic differentiation between harbor porpoise in the northern and southern regions
  on the inland waters of southeast Alaska. Geographic delineation is not yet known. Data to evaluate population structure for harbor porpoise in
  Southeast Alaska have been collected and are currently being analyzed. Should the analysis identify different population structure than is currently
  reflected in the Alaska SARs, NMFS will consider how to best revise stock designations in the future.


[[Page 26438]]

    Twelve species (with 23 managed stocks) are considered to have the 
potential to co-occur with Coast Guard activities to the degree that 
take is likely to occur. Table 4 identifies which stocks are expected 
to occur near each of the Coast Guard facilities. There are several 
species or stocks that occur in Gulf of Alaska waters, but which are 
not expected to occur in the vicinity of any of the eight Coast Guard 
facilities. In addition, the sea otter is found in coastal waters. 
However, sea otters are managed by the U.S. Fish and Wildlife Service 
and are not considered further in this document.
BILLING CODE 3510-22-P

[[Page 26439]]

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[[Page 26440]]


[GRAPHIC] [TIFF OMITTED] TP28AP23.003

BILLING CODE 3510-22-C
    As indicated above, all 12 species (and 23 managed stocks) in Table 
3 temporally and spatially co-occur with the activity to the degree 
that take is reasonably likely to occur, and we have proposed 
authorizing it. While Cuvier's beaked whales have been reported near 
all eight project areas, the spatial occurrence of this species 
generally offshore in deep water is such that take is not expected to 
occur, and it is not discussed further beyond the explanation provided 
here.

Gray Whale

    Gray whales occur exclusively in the North Pacific Ocean. The 
Eastern North Pacific stock of gray whales inhabit California and 
Mexico in the winter months, and the Chukchi, Beaufort, and Bering Seas 
in northern Alaska in the summer and fall. Gray whales have also been 
observed feeding in waters off Southeast Alaska during the summer 
(NMFS, 2022). The migration pattern of gray whales appears to follow a 
route along the western coast of Southeast Alaska, traveling northward 
from British Columbia through Hecate Strait and Dixon Entrance, passing 
the west coast of Baranof Island from late March to May and then return 
south in October and November (Jones et al., 1984, Ford et al., 2012).
    Two populations of gray whales are recognized, the eastern and a 
western North Pacific (ENP and WNP). WNP whales are known to feed in 
the Okhotsk Sea and off of Kamchatka before migrating south to poorly 
known wintering grounds, possibly in the South China Sea. The two 
populations have historically been considered geographically isolated 
from each other; however, data from satellite-tracked whales indicate 
that there is some overlap between the stocks. Two WNP whales were 
tracked from Russian foraging areas along the Pacific rim to Baja 
California (Mate et al., 2011), and, in one case where the satellite 
tag remained attached to the whale for a longer period, a WNP whale was 
tracked from Russia to Mexico and back again (IWC, 2012). Between 22-24 
WNP whales are known to have occurred in the eastern Pacific through 
comparisons of ENP and WNP photo-identification catalogs (IWC, 2012; 
Weller et al., 2011; Burdin et al., 2011). Urban et al. (2013) compared 
catalogs of photo-identified individuals from Mexico with photographs 
of whales off Russia and reported a total of 21 matches. Therefore, a 
portion of the WNP population is assumed to migrate, at least in some 
years, to the eastern Pacific during the winter breeding season. 
However, it is extremely unlikely that a gray whale in close proximity 
to Coast Guard construction activity would be one of the few WNP whales 
that have been documented in the eastern Pacific. The likelihood that a 
WNP whale would be present in the vicinity of Coast Guard construction 
activities at all locations is insignificant and discountable, and WNP 
gray whales are omitted from further analysis.
    Kodiak, Sitka, and Juneau are within a gray whale migratory 
corridor Biologically Important Area (BIA) (Ferguson et al., 2015).

Humpback Whale

    Humpback whales are the most commonly observed baleen whale in 
Alaska and have been observed in Southeast Alaska in all months of the 
year (Baker et al., 1986). They undergo seasonal migration with more 
whales present in Alaska from spring until fall. There are two 
potential stocks of humpback whales that may occur in the project area: 
the Central North Pacific stock and the Western North Pacific stock. 
The Central North Pacific stock consists of winter/spring populations 
of the Hawaiian Islands and Mexico, which migrate primarily to northern 
British Columbia/Southeast Alaska, the Gulf of Alaska, and the Bering 
Sea/Aleutian Islands (Baker et al., 1990; Perry et al., 1990; 
Calambokidis et al., 1997). The Western North Pacific stock consists of 
winter/spring populations off Asia, which migrate primarily to Russia 
and the Bering Sea/Aleutian Islands. Members of the Western North 
Pacific stock have the potential to occur at Base Kodiak and in the 
vicinity of Seward moorings, whereas members of the Central North 
Pacific stock have the potential to occur at any of the eight 
facilities.
    Prior to 2016, humpback whales were listed under the ESA as an 
endangered species worldwide. Following a 2015 global status review 
(Bettridge et al., 2015), NMFS established 14 DPSs with different 
listing statuses (81 FR 62259, September 8, 2016) pursuant to the ESA. 
The DPSs that occur in U.S. waters do not necessarily equate to the 
existing stocks designated under the MMPA and shown in Table 3. Because 
MMPA stocks cannot be portioned, i.e., parts managed as ESA-listed 
while other parts managed as not ESA-listed, until such time as the 
MMPA stock delineations are reviewed in light of the DPS designations, 
NMFS considers the existing humpback whale stocks under the MMPA to be 
endangered and depleted for MMPA management purposes.
    Within Alaska waters, three current DPSs may occur: the Hawaii DPS 
(not listed), the Western North Pacific DPS (endangered), and the 
Mexico DPS (threatened). Humpback whales found in the project areas are 
predominantly members of the Hawaii DPS (98 percent probability in 
Southeast Alaska (Sitka, Ketchikan, Juneau, and Petersburg sites), 89 
percent in the Gulf of Alaska (Kodiak, Seward, Valdez, and Cordova 
sites), and 91 percent in the Aleutian Islands), which is not listed 
under the ESA. However, based on a comprehensive photo-identification 
study, members of the Mexico DPS, which is listed as threatened, have a 
small potential to occur in all project locations (2 percent 
probability in Southeast Alaska, 11 percent in Gulf of Alaska, and 7 
percent in the Aleutian Islands), and members of the Western North 
Pacific DPS have a small potential to occur in the Aleutian Islands (2 
percent probability) and the Gulf of Alaska (1 percent probability) 
(Wade 2021).
    On January 24, 2023, NMFS published the draft 2022 SARs (https://

[[Page 26441]]

www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-
stock-assessment-reports-region). The Alaska and Pacific Ocean SARs 
include proposed updates to the humpback whale and harbor porpoise 
stock structures. The new humpback whale stock structure, if finalized, 
would modify the MMPA-designated stocks to align more closely with the 
ESA-designated DPSs. The new harbor porpoise stock structure, if 
finalized, would split the Southeast Alaska stock into three new 
stocks. Please refer to the draft 2022 Alaska (Young et al., 2023) and 
Pacific Ocean SARs for additional information.
    NMFS' Office of Protected Resources, Permits and Conservation 
Division has generally considered peer-reviewed data in draft SARs 
(relative to data provided in the most recent final SARs), when 
available, as the best available science, and has done so in this 
proposed rule for all species and stocks, with the exception of a new 
proposal to revise humpback whale and harbor porpoise stock structures. 
Given that the proposed changes involve application of NMFS' Guidance 
for Assessing Marine Mammals Stocks and could be revised following 
consideration of public comments, it is more appropriate to conduct our 
analysis in this proposed rule based on the status quo stock structure 
identified in the most recent final SARs (2021; Carretta et al., 2022; 
Muto et al., 2022).
    Critical habitat was recently finalized for the humpback whale in 
Alaska (86 FR 21082, April 21, 2021). Designated critical habitat for 
the Western North Pacific and Mexico DPSs overlaps Kodiak Island; 
Cordova and Valdez are located near, but not within, critical habitat 
for the Mexico DPS. Kodiak, Sitka, Juneau, and Petersburg are within 
seasonal humpback whale feeding BIAs (Ferguson et al., 2015).

Fin Whale

    The fin whale is widely distributed in all the world's oceans 
(Gambell, 1985), but typically occurs in temperate and polar regions 
from 20-70[deg] north and south of the Equator (Perry et al., 1999). 
Fin whales occur in coastal, shelf, and oceanic waters. Sergeant (1977) 
suggested that fin whales tend to follow steep slope contours, either 
because they detect them readily or because biological productivity is 
high along steep contours because of mixing. Stafford et al. (2009) 
noted that sea-surface temperature is a good predictor variable for fin 
whale call detections in the North Pacific.
    Fin whales appear to have complex seasonal movements and are 
seasonal migrants; they mate and calve in temperate waters during the 
winter and migrate to feed at northern latitudes during the summer 
(Gambell, 1985). The North Pacific population summers from the Chukchi 
Sea to California and winters from California southwards (Gambell, 
1985). Aggregations of fin whales are found year-round off southern and 
central California (Dohl et al., 1980, 1983; Forney et al., 1995; 
Barlow, 1997) and in the summer off Oregon (Green et al., 1992; Edwards 
et al., 2015). Diet for the fin whale varies by location and 
availability, but includes primarily krill, large copepods, some small 
squid, and small schooling fish (Cooke, 2018). Much of foraging occurs 
in spring, summer, and fall, with fasting or minimal feeding occurring 
during winter. Fin whales are generally solitary but can also occur in 
groups of two to seven individuals. Larger aggregations are usually due 
to gatherings at concentrated food sources and individuals display no 
social bonds (Wiles, 2017). The project site in Kodiak is just outside 
the fin whale feeding BIA, which cuts off at the mouth of Chiniak Bay 
where Base Kodiak is located.

Minke Whale

    Minke whales are found throughout the northern hemisphere in polar, 
temperate, and tropical waters. The International Whaling Commission 
has identified three minke whale stocks in the North Pacific: one near 
the Sea of Japan, a second in the rest of the western Pacific (west of 
180[deg] W), and a third, less concentrated stock throughout the 
eastern Pacific. NMFS further splits this third stock between Alaska 
whales and resident whales of California, Oregon, and Washington (Muto 
et al., 2018). Minke whales are found in all Alaska waters, however no 
population estimates are currently available for the Alaska stock.
    In Alaska, minke whales feed primarily on euphausiids and walleye 
pollock. Minke whales are generally found in shallow, coastal waters 
within 200 m (656 ft) of shore (Zerbini et al., 2006). Dedicated 
surveys for cetaceans in southeast Alaska found that minke whales were 
scattered throughout inland waters from Glacier Bay and Icy Strait to 
Clarence Strait, with small concentrations near the entrance of Glacier 
Bay. Surveys took place in spring, summer, and fall, and minke whales 
were present in low numbers in all seasons and years (Dahlheim et al., 
2009). Additionally, minke whales were observed during the Biorka 
Island Dock Replacement Project at the mouth of Sitka Sound (Turnagain 
Marine Construction, 2018).

Killer Whale

    Killer whales have been observed in all oceans, but the highest 
densities occur in colder and more productive waters found at high 
latitudes. Killer whales occur along the entire coast of Alaska (Braham 
and Dahlheim, 1982), inland waterways of British Columbia and 
Washington (Bigg et al., 1990), and along the outer coasts of 
Washington, Oregon, and California (Green et al., 1992; Barlow, 1995, 
1997; Forney et al., 1995). Eight stocks of killer whales are 
recognized within the Pacific U.S. Exclusive Economic Zone (Muto et 
al., 2020). Of those, five stocks may be present in the project areas 
as follows: (1) Alaska Resident stock--All project locations; (2) AT1 
Transient stock--Cordova, Valdez, and Seward; (3) Gulf of Alaska, 
Aleutian Islands, and Bering Sea Transient stock--Kodiak, Sitka, 
Valdez, Cordova, and Seward; (4) Northern Resident--Juneau, Sitka, 
Petersburg, and Ketchikan; and (5) West Coast Transient stock--Juneau, 
Sitka, Petersburg, and Ketchikan. Table 4 outlines where each stock is 
expected to overlap with each project location.
    Transient killer whales hunt and feed primarily on marine mammals, 
including harbor seals, Dall's porpoises, harbor porpoises, and sea 
lions. Resident killer whale populations in the eastern North Pacific 
feed mainly on salmonids, showing a strong preference for Chinook 
salmon (Muto et al., 2020).
    The Alaska Resident stock occurs from southeast Alaska to the 
Aleutian Islands and Bering Sea. The Northern Resident stock occurs 
from Washington north through part of southeast Alaska. The Gulf of 
Alaska, Aleutian Islands, and Bering Sea Transient stock occurs from 
the northern British Columbia coast to the Aleutian Islands and Bering 
Sea. The AT1 Transient stock occurs only in Prince William Sound and in 
the Kenai Fjords region. The West Coast Transient stock occurs from 
California north through southeast Alaska (Muto et al., 2020).
    Dahlheim et al., (2009) noted a 5.2 percent annual decline in 
transient killer whales observed in southeast Alaska between 1991 and 
2007. Both resident and transient killer whales were observed in 
southeast Alaska during all seasons during surveys between 1991 and 
2007, in a variety of habitats and in all major waterways, including 
Lynn Canal, Icy Strait, Stephens Passage, Frederick Sound, and upper 
Chatham Strait (Dahlheim et al., 2009). There does not appear to be 
strong seasonal variation in abundance

[[Page 26442]]

or distribution of killer whales, but Dahlheim et al. (2009) observed 
substantial variability among different years.
    Members of the fish-eating resident stocks are the most commonly 
seen in nearshore waters with members of the Alaska Resident stock 
having the potential to occur at any of the facilities while Northern 
Resident individuals have the potential to occur at all of the 
facilities except Base Ketchikan which is south of their expected range 
(Muto et al., 2020). Transient killer whales of the Gulf of Alaska, 
Aleutian Islands, and Bering Sea stock have the potential to occur at 
all facilities except those facilities along the Inside Passage (i.e., 
Base Ketchikan, Petersburg Moorings, and Station Juneau). Southeast 
Alaska is at the northern limit of the West Coast Transient stock and 
individuals of this population are only anticipated to appear at 
Station Sitka, Base Ketchikan, Station Juneau, and Petersburg Moorings.

Pacific White-Sided Dolphin

    The Pacific white-sided dolphin is found in cool temperate waters 
of the North Pacific from the southern Gulf of California to Alaska. 
Across the North Pacific, it appears to have a relatively narrow 
distribution between 38[deg] N and 47[deg] N (Brownell et al., 1999). 
In the eastern North Pacific Ocean, the Pacific white-sided dolphin is 
one of the most common cetacean species, occurring primarily in shelf 
and slope waters (Green et al., 1993; Barlow 2003, 2010).
    Results of aerial and shipboard surveys strongly suggest seasonal 
north-south movements of the species between California and Oregon/
Washington; the movements apparently are related to oceanographic 
influences, particularly water temperature (Green et al., 1993; Forney 
and Barlow, 1998; Buchanan et al., 2001). During winter, this species 
is most abundant in California slope and offshore areas; as northern 
waters begin to warm in the spring, it appears to move north to slope 
and offshore waters off Oregon/Washington (Green et al., 1992, 1993; 
Forney et al., 1995; Buchanan et al., 2001; Barlow 2003).
    Pacific white-sided dolphins are highly gregarious with groups 
usually between 10 and 100 animals but ranging up to the thousands.

Dall's Porpoise

    Dall's porpoise is found in temperate to subarctic waters of the 
North Pacific and adjacent seas (Jefferson et al., 2015). It is widely 
distributed across the North Pacific over the continental shelf and 
slope waters, and over deep (2500 m and greater) oceanic waters (Hall, 
1979). It is probably the most abundant small cetacean in the North 
Pacific Ocean, and its abundance changes seasonally, likely in relation 
to water temperature (Becker, 2007). They occur in groups of up to 25 
individuals and are expected to occur at all eight facilities.

Harbor Porpoise

    Harbor porpoise are common in coastal waters. They frequently occur 
in coastal waters of southeast Alaska and are observed most frequently 
in waters less than 350 ft (107 m) deep (Dahlheim et al., 2009). There 
are three harbor porpoise stocks in Alaska: (1) The Southeast Alaska 
stock occurs from Dixon Entrance to Cape Suckling, including inland 
waters; (2) The Gulf of Alaska stock occurs from Cape Suckling to 
Unimak Pass; and (3) The Bering Sea stock occurs throughout the 
Aleutian Islands and all waters north of Unimak Pass (Muto et al., 
2021). Only the Southeast Alaska stock and the Gulf of Alaska stock are 
expected to be encountered throughout all project sites. The Southeast 
Alaska stock's range includes the Sitka, Ketchikan, Juneau, and 
Petersburg facilities, while the Gulf of Alaska stock range includes 
the Kodiak, Valdez, Seward, and Cordova facilities.

California Sea Lion

    The primary range of the California sea lion includes the coastal 
areas and offshore islands of the eastern North Pacific Ocean from 
British Columbia to central Mexico, including the Gulf of California 
(Jefferson et al., 2015). However, its distribution is expanding 
(Jefferson et al., 2015), and its secondary range extends into the Gulf 
of Alaska (Maniscalco et al., 2004) and southern Mexico (Gallo-Reynoso 
and Sol[oacute]rzano-Velasco, 1991).
    In California and Baja California, births occur on land from mid-
May to late-June. During August and September, after the mating season, 
the adult males migrate northward to feeding areas (Lowry et al., 
1992). They remain there until spring (March-May), when they migrate 
back to the breeding colonies (Lowry et al., 1992; Weise et al., 2006). 
The distribution of immature California sea lions is less well known 
but some make northward migrations that are shorter in length than the 
migrations of adult males (Huber, 1991). However, most immature seals 
are presumed to remain near the rookeries for most of the year, as are 
females and pups (Lowry et al., 1992).

Northern Fur Seal

    The northern fur seal is endemic to the North Pacific Ocean and 
occurs from southern California to the Bering Sea, Sea of Okhotsk, and 
Sea of Japan (Jefferson et al., 2015). The worldwide population of 
northern fur seals has declined substantially from 1.8 million animals 
in the 1950s (Muto et al., 2020). They were subjected to large-scale 
harvests on the Pribilof Islands to supply a lucrative fur trade. Two 
stocks are recognized in U.S. waters: The Eastern North Pacific and the 
California stocks. The Eastern Pacific stock ranges from southern 
California during winter to the Pribilof Islands and Bogoslof Island in 
the Bering Sea during summer (Carretta et al., 2020; Muto et al., 
2020). Abundance of the Eastern Pacific Stock has been decreasing at 
the Pribilof Islands since the 1940s and increasing on Bogoslof Island. 
The northern fur seal population appears to be greatly affected by El 
Ni[ntilde]o events.
    Most northern fur seals are highly migratory. During the breeding 
season, most of the world's population of northern fur seals occurs on 
the Pribilof and Bogoslof islands (NMFS 2007). The main breeding season 
is in July (Gentry, 2009). Adult males usually occur onshore from May 
to August, though some may be present until November; females are 
usually found ashore from June to November (Muto et al., 2020). Nearly 
all fur seals from the Pribilof Island rookeries are foraging at sea 
from fall through late spring. In November, females and pups leave the 
Pribilof Islands and migrate through the Gulf of Alaska to feeding 
areas primarily off the coasts of British Columbia, Washington, Oregon, 
and California before migrating north again to the rookeries in spring 
(Ream et al., 2005; Pelland et al., 2014). Immature seals can remain at 
sea in southern foraging areas year-round until they are old enough to 
mate (Muto et al., 2022). Adult males migrate only as far south as the 
Gulf of Alaska or to the west off the Kuril Islands (Kajimura, 1984).
    The northern fur seal spends approximately 90 percent of its time 
at sea, typically in areas of upwelling along the continental slopes 
and over seamounts (Gentry, 1981). The remainder of its life is spent 
on or near rookery islands or haulouts. While at sea, northern fur 
seals usually occur singly or in pairs, although larger groups can form 
in waters rich with prey (Antonelis and Fiscus, 1980; Gentry, 1981). 
Northern fur seals dive to relatively shallow depths to feed: 100-200 m 
for females, and <400 m for males (Gentry, 2009). Tagged adult female 
fur

[[Page 26443]]

seals were shown to remain within 200 km of the shelf break (Pelland et 
al., 2014).

Steller Sea Lion

    The Steller sea lion's range extends across the North Pacific Rim 
from northern Japan to California with areas of abundance in the Gulf 
of Alaska and Aleutian Islands (Muto et al., 2020). In 1997, based on 
demographic and genetic dissimilarities, NMFS identified two DPSs of 
Steller sea lions under the ESA: a western DPS (western stock) and an 
eastern DPS (eastern stock). The western DPS breeds on rookeries 
located west of 144[deg] W in Alaska and Russia, whereas the eastern 
DPS breeds on rookeries in southeast Alaska through California.
    Movement occurs between the western and eastern DPS of Steller sea 
lions, and increasing numbers of individuals from the western DPS have 
been seen in Southeast Alaska in recent years (Muto et al., 2020, Fritz 
et al., 2016; DeMaster, 2014). This DPS-exchange is especially evident 
in the outer southeast coast of Alaska, including Sitka Sound. The 
distribution of marked animals (along with other demographic data) 
indicates that movements of Steller sea lions during the breeding 
season result in a small net annual movement of animals from southeast 
Alaska (eastern DPS) to the western DPS (approximately 80 sea lions 
total) but a much larger inter-regional movement between the western 
DPS and the eastern DPS (approximately 1,000 sea lions per year; Fritz 
et al., 2016). Hastings et al. (2020) indicates that the eastern 
population is increasing while the western population is decreasing, 
influencing mixing of both populations at new rookeries in northern 
southeast Alaska. They estimate 38 percent and 13 percent of animals in 
the northern outer coast from the Glacier Bay and Lynn Canal in 
southeast Alaska carry genetic information unique to the western 
population.
    Critical habitat has been defined in Alaska at major haulouts and 
major rookeries (50 CFR 226.202), but the project action areas do not 
overlap with Steller sea lion critical habitat. Additionally, no in-
water work will occur from March 1 through October 1 at Valdez and 
Cordova to avoid overlap with Steller sea lion breeding season.

Harbor Seal

    Harbor seals are common in the coastal and inside waters of the 
project areas. Harbor seals in Alaska are typically non-migratory with 
local movements attributed to factors such as prey availability, 
weather, and reproduction (Scheffer and Slipp, 1944; Fisher, 1952; Bigg 
1969, 1981; Hastings et al., 2004). Harbor seals haul out of the water 
periodically to rest, give birth, and nurse their pups. According to 
the NMFS Alaska Fisheries Science Center (AFSC, 2021) there is one 
haulout near Valdez (HG08A), and one near Cordova (GG08D) that are 
within direct line of sight and that could be exposed in larger Level B 
harassment zones (see below).
    There are 12 stocks of harbor seals in Alaska, 5 of which occur in 
the project areas: (1) the South Kodiak stock ranges from Middle Cape 
on the west coast of Kodiak Island southwest to Chirikof Island and 
east along the south coast of Kodiak Island to Spruce Island; (2) the 
Prince William Sound stock ranges from Elizabeth Island off the 
southwest tip of the Kenai Peninsula to Cape Fairweather; (3) the Lynn 
Canal/Stephens Passage stock ranges north along the east and north 
coast of Admiralty Island from the north end of Kupreanof Island 
through Lynn Canal; (4) the Sitka/Chatham Strait stock ranges from Cape 
Bingham south to Cape Ommaney, extending inland to Table Bay on the 
west side of Kuiu Island and north through Chatham Strait to Cube Point 
off the west coast of Admiralty Island, and as far east as Cape Bendel 
on the northeast tip of Kupreanof Island; and (5) the Clarence Strait 
stock ranges along the east coast of Prince of Wales Island from Cape 
Chacon north through Clarence Strait to Point Baker and along the east 
coast of Mitkof and Kupreanof Islands north to Bay Point.

Unusual Mortality Events (UME)

    A UME is defined under the MMPA as ``a stranding that is 
unexpected; involves a significant die-off of any marine mammal 
population; and demands immediate response.'' The only currently 
ongoing UME investigation involves gray whales (https://www.fisheries.noaa.gov/national/marine-life-distress/2019-2021-gray-whale-unusual-mortality-event-along-west-coast-and. Beginning in early 
2019, elevated strandings were observed along the west coast, with the 
majority of strandings in Alaska. Findings to date indicate that the 
whales are often emaciated but a cause of the UME has not been 
determined.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2016) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65-
decibel (dB) threshold from the normalized composite audiograms, with 
an exception for lower limits for low-frequency cetaceans where the 
result was deemed to be biologically implausible and the lower bound 
from Southall et al. (2007) retained. Marine mammal hearing groups and 
their associated hearing ranges are provided in Table 5.

                  Table 5--Marine Mammal Hearing Groups
                              [NMFS, 2018]
------------------------------------------------------------------------
               Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen         7 Hz to 35 kHz.
 whales).
Mid-frequency (MF) cetaceans (dolphins,      150 Hz to 160 kHz.
 toothed whales, beaked whales, bottlenose
 whales).
High-frequency (HF) cetaceans (true          275 Hz to 160 kHz.
 porpoises, Kogia, river dolphins,
 cephalorhynchid, Lagenorhynchus cruciger &
 L. australis)..
Phocid pinnipeds (PW) (underwater) (true     50 Hz to 86 kHz.
 seals).

[[Page 26444]]

 
Otariid pinnipeds (OW) (underwater) (sea     60 Hz to 39 kHz.
 lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Please refer to Table 3.

Potential Effects of the Specified Activity on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take section, and the Proposed Mitigation section, to draw 
conclusions regarding the likely impacts of these activities on the 
reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.
    In the following discussion, we provide general background 
information on sound before considering potential effects to marine 
mammals from sound produced by pile driving.

Description of Sound Sources

    This section contains a brief technical background on sound, on the 
characteristics of certain sound types, and on metrics used in this 
proposal inasmuch as the information is relevant to the specified 
activity and to a discussion of the potential effects of the specified 
activity on marine mammals found later in this document.
    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far (ANSI 1994, 1995). The sound level of an area 
is defined by the total acoustical energy being generated by known and 
unknown sources. These sources may include physical (e.g., waves, wind, 
precipitation, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activity may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.
    In-water construction activities associated with the project would 
include impact pile driving, vibratory pile driving, DTH, pile cutting, 
and power washing. Of these sounds, pile cutting and power washing are 
not expected to cause take of marine mammals and are thus not addressed 
further. The sounds produced by these activities fall into one of two 
general sound types: intermittent impulsive and continuous, non-
impulsive. Impulsive sounds (e.g., explosions, gunshots, sonic booms, 
impact pile driving) are typically transient, brief (less than 1 
second), broadband, and consist of high peak sound pressure with rapid 
rise time and rapid decay (ANSI, 1986; NIOSH, 1998; ANSI, 2005; NMFS, 
2018). As regards the temporal aspect of these sound types, impulsive 
sounds are inherently intermittent, while non-impulsive sounds may be 
intermittent or continuous. Non-impulsive sounds (e.g., machinery 
operations such as drilling or dredging, vibratory pile driving, pile 
cutting, power washing, and active sonar systems) can be broadband, 
narrowband or tonal, brief or prolonged (continuous or intermittent), 
and typically do not have the high peak sound pressure with raid rise/
decay time that impulsive sounds do (ANSI 1995; NIOSH 1998; NMFS 2018). 
The distinction between these two sound types is important because they 
have differing potential to cause physical effects, particularly with 
regard to hearing (e.g., Ward 1997 in Southall et al., 2007).
    Three types of pile hammers would be used on this project: impact, 
vibratory, and DTH. Impact hammers operate by repeatedly dropping a 
heavy piston onto a pile to drive the pile into the substrate. Sound 
generated by impact hammers is characterized by rapid rise times and 
high peak levels, a potentially injurious combination (Hastings and 
Popper, 2005). Vibratory hammers install piles by vibrating them and 
allowing the weight of the hammer to push them into the sediment. 
Vibratory hammers produce significantly less sound than impact hammers. 
Peak sound pressure levels (SPLs) may be 180 dB or greater, but are 
generally 10 to 20 dB lower than SPLs generated during impact pile 
driving of the same-sized pile (Oestman et al., 2009). Rise time is 
slower, reducing the probability and severity of injury, and sound 
energy is distributed over a greater amount of time (Nedwell and 
Edwards, 2002; Carlson et al., 2005).
    Rock or tension anchoring would be conducted using a DTH hammer. A 
DTH hammer is essentially a drill bit that drills through the bedrock 
using a rotating function like a normal drill in concert with a 
hammering pulse mechanism operated by a pneumatic (or sometimes 
hydraulic) component

[[Page 26445]]

integrated into the DTH hammer to increase speed of progress through 
the substrate (i.e., it is similar to a ``hammer drill'' hand tool). 
Rock anchoring or socketing involves using DTH equipment to create a 
hole in the bedrock inside which the pile is placed to give it lateral 
and longitudinal strength. Tension anchoring involves creating a 
smaller hole below the bottom of a pile. A length of rebar is typically 
inserted in the small hole and is long enough to run up through the 
middle of a hollow pile to reach the surface where it is connected to 
the pile to provide additional mechanical support and stability to the 
pile. The sounds produced by DTH systems contain both a continuous, 
non-impulsive component from the drilling action and an impulsive 
component from the hammering effect. Therefore, NMFS treats DTH systems 
as both impulsive (for estimating Level A harassment zones) and non-
impulsive (for estimating Level B harassment zones) sound source types 
simultaneously.
    The likely or possible impacts of the Coast Guard's proposed 
activity on marine mammals could involve both non-acoustic and acoustic 
stressors. Potential non-acoustic stressors could result from the 
physical presence of the equipment and personnel; however, any impacts 
to marine mammals are expected to primarily be acoustic in nature. 
Acoustic stressors include effects of heavy equipment operation during 
pile driving and removal.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from DTH and pile driving is the primary means by which 
marine mammals may be harassed from the Coast Guard's specified 
activity. In general, animals exposed to natural or anthropogenic sound 
may experience physical and psychological effects, ranging in magnitude 
from none to severe (Southall et al., 2007). Generally, exposure to 
pile driving noise has the potential to result in auditory threshold 
shifts and behavioral reactions (e.g., avoidance, temporary cessation 
of foraging and vocalizing, changes in dive behavior). Exposure to 
anthropogenic noise can also lead to non-observable physiological 
responses such an increase in stress hormones. Additional noise in a 
marine mammal's habitat can mask acoustic cues used by marine mammals 
to carry out daily functions such as communication and predator and 
prey detection. The effects of pile driving noise on marine mammals are 
dependent on several factors, including, but not limited to, sound type 
(e.g., impulsive vs. non-impulsive), the species, age and sex class 
(e.g., adult male vs. mom with calf), duration of exposure, the 
distance between the pile and the animal, received levels, behavior at 
time of exposure, and previous history with exposure (Wartzok et al., 
2004; Southall et al., 2007). Here we discuss physical auditory effects 
(threshold shifts) followed by behavioral effects and potential impacts 
on habitat.
    NMFS defines a noise-induced threshold shift (TS) as a change, 
usually an increase, in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). The amount of 
threshold shift is customarily expressed in dB. A TS can be permanent 
or temporary. As described in NMFS (2018), there are numerous factors 
to consider when examining the consequence of TS, including, but not 
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), likelihood an individual would be exposed for a long enough 
duration or to a high enough level to induce a TS, the magnitude of the 
TS, time to recovery (seconds to minutes or hours to days), the 
frequency range of the exposure (i.e., spectral content), the hearing 
and vocalization frequency range of the exposed species relative to the 
signal's frequency spectrum (i.e., how an animal uses sound within the 
frequency band of the signal; e.g., Kastelein et al., 2014), and the 
overlap between the animal and the source (e.g., spatial, temporal, and 
spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals indicate that a 40 dB threshold 
shift approximates PTS onset (see Ward et al., 1958, 1959; Ward 1960; 
Kryter et al., 1966; Miller 1974; Ahroon et al., 1996; Henderson et 
al., 2008). PTS levels for marine mammals are estimates, as with the 
exception of a single study unintentionally inducing PTS in a harbor 
seal (Kastak et al., 2008), there are no empirical data measuring PTS 
in marine mammals largely due to the fact that, for various ethical 
reasons, experiments involving anthropogenic noise exposure at levels 
inducing PTS are not typically pursued or authorized (NMFS 2018).
    Temporary Threshold Shift (TTS)--TTS is a temporary, reversible 
increase in the threshold of audibility at a specified frequency or 
portion of an individual's hearing range above a previously established 
reference level (NMFS 2018). Based on data from cetacean TTS 
measurements (see Southall et al., 2007), a TTS of 6 dB is considered 
the minimum threshold shift clearly larger than any day-to-day or 
session-to-session variation in a subject's normal hearing ability 
(Schlundt et al., 2000; Finneran et al., 2000, 2002). As described in 
Finneran (2015), marine mammal studies have shown the amount of TTS 
increases with cumulative sound exposure level (SELcum) in an 
accelerating fashion: At low exposures with lower SELcum, the amount of 
TTS is typically small and the growth curves have shallow slopes. At 
exposures with higher SELcum, the growth curves become steeper and 
approach linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during a time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al., 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Many studies have examined noise-induced hearing loss in marine 
mammals (see Finneran (2015) and Southall et al. (2019) for summaries). 
For cetaceans, published data on the onset of TTS are limited to the 
captive bottlenose dolphin (Tursiops truncatus), beluga whale 
(Delphinapterus leucas), harbor porpoise, and Yangtze finless porpoise 
(Neophocoena asiaeorientalis), and for pinnipeds in water, measurements 
of TTS are limited to harbor seals, elephant seals (Mirounga 
angustirostris), and California sea lions. These studies examine 
hearing thresholds measured in marine mammals before and after exposure 
to

[[Page 26446]]

intense sounds. The difference between the pre-exposure and post-
exposure thresholds can be used to determine the amount of threshold 
shift at various post-exposure times. The amount and onset of TTS 
depends on the exposure frequency. Sounds at low frequencies, well 
below the region of best sensitivity, are less hazardous than those at 
higher frequencies, near the region of best sensitivity (Finneran and 
Schlundt, 2013). At low frequencies, onset-TTS exposure levels are 
higher compared to those in the region of best sensitivity (i.e., a low 
frequency noise would need to be louder to cause TTS onset when TTS 
exposure level is higher), as shown for harbor porpoises and harbor 
seals (Kastelein et al., 2019a, 2019b). In addition, TTS can accumulate 
across multiple exposures, but the resulting TTS will be less than the 
TTS from a single, continuous exposure with the same SEL (Finneran et 
al., 2010; Kastelein et al., 2014; Kastelein et al., 2015a; Mooney et 
al., 2009). This means that TTS predictions based on the total, SELcum 
will overestimate the amount of TTS from intermittent exposures such as 
sonars and impulsive sources. Nachtigall et al., (2018) describe the 
measurements of hearing sensitivity of multiple odontocete species 
(bottlenose dolphin, harbor porpoise, beluga, and false killer whale 
(Pseudorca crassidens)) when a relatively loud sound was preceded by a 
warning sound. These captive animals were shown to reduce hearing 
sensitivity when warned of an impending intense sound. Based on these 
experimental observations of captive animals, the authors suggest that 
wild animals may dampen their hearing during prolonged exposures or if 
conditioned to anticipate intense sounds. Another study showed that 
echolocating animals (including odontocetes) might have anatomical 
specializations that might allow for conditioned hearing reduction and 
filtering of low-frequency ambient noise, including increased stiffness 
and control of middle ear structures and placement of inner ear 
structures (Ketten et al., 2021). Data available on noise-induced 
hearing loss for mysticetes are currently lacking (NMFS, 2018).
    Installing piles requires a combination of impact pile driving, 
vibratory pile driving, and DTH. For the project, these activities 
would not occur at the same time and there would likely be pauses in 
activities producing the sound during each day. Given these pauses and 
that many marine mammals are likely moving through the action area and 
not remaining for extended periods of time, the potential for TS 
declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
drilling also has the potential to behaviorally disturb marine mammals. 
Available studies show wide variation in response to underwater sound; 
therefore, it is difficult to predict specifically how any given sound 
in a particular instance might affect marine mammals perceiving the 
signal. If a marine mammal does react briefly to an underwater sound by 
changing its behavior or moving a small distance, the impacts of the 
change are unlikely to be significant to the individual, let alone the 
stock or population. However, if a sound source displaces marine 
mammals from an important feeding or breeding area for a prolonged 
period, impacts on individuals and populations could be significant 
(e.g., Lusseau and Bejder, 2007; Weilgart, 2007; NRC, 2005).
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, or moving direction and/or speed; 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping); avoidance of areas where sound sources are located. 
Pinnipeds may increase their haul out time, possibly to avoid in-water 
disturbance (Thorson and Reyff, 2006). Behavioral responses to sound 
are highly variable and context-specific and any reactions depend on 
numerous intrinsic and extrinsic factors (e.g., species, state of 
maturity, experience, current activity, reproductive state, auditory 
sensitivity, time of day), as well as the interplay between factors 
(e.g., Richardson et al., 1995; Wartzok et al., 2003; Southall et al., 
2007; Weilgart, 2007; Archer et al., 2010). Behavioral reactions can 
vary not only among individuals but also within an individual, 
depending on previous experience with a sound source, context, and 
numerous other factors (Ellison et al., 2012), and can vary depending 
on characteristics associated with the sound source (e.g., whether it 
is moving or stationary, number of sources, distance from the source). 
In general, pinnipeds seem more tolerant of, or at least habituate more 
quickly to, potentially disturbing underwater sound than do cetaceans, 
and generally seem to be less responsive to exposure to industrial 
sound than most cetaceans. Please see Appendices B and C of Southall et 
al. (2007) for a review of studies involving marine mammal behavioral 
responses to sound.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al., 
2007). A determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    In 2016, the Alaska Department of Transportation and Public 
Facilities (ADOT&PF) documented observations of marine mammals during 
construction activities (i.e., pile driving and DTH drilling) at the 
Kodiak Ferry Dock (see 80 FR 60636, October 7, 2015). In the marine 
mammal monitoring report for that project (ABR 2016), 1,281 Steller sea 
lions were observed within the estimated Level B harassment zone during 
pile driving or drilling. Of these, 19 individuals demonstrated an 
alert behavior, 7 were fleeing, and 19 swam away from the project site. 
All other animals (98 percent) were engaged in activities such as 
milling, foraging, or fighting and did not change their behavior. In 
addition, two sea lions approached within 20 meters of active vibratory 
pile driving activities. Three harbor seals were observed within the 
disturbance zone during pile driving activities; none of them displayed 
disturbance behaviors. Fifteen killer whales and three harbor porpoises 
were also observed within the estimated Level B harassment zone during 
pile driving. The killer whales were travelling or milling while all 
harbor porpoises were travelling. No signs of disturbance were noted 
for either of these species. Given the similarities in activities and 
habitat and the fact the same species are involved, we expect similar 
behavioral responses of marine mammals to the Coast Guard's specified 
activity. That is, disturbance, if any, is likely to be temporary and 
localized (e.g., small area movements). Monitoring reports from other 
recent pile driving and DTH projects in Alaska

[[Page 26447]]

have observed similar behaviors (for example, the Biorka Island Dock 
Replacement Project https://www.fisheries.noaa.gov/action/incidental-take-authorization-faa-biorka-island-dock-replacement-project-sitka-ak).
    Airborne Acoustic Effects--Pinnipeds that occur near the project 
sites could be exposed to airborne sounds associated with pile driving 
or DTH that have the potential to cause behavioral harassment, 
depending on their distance from the activities. Cetaceans are not 
expected to be exposed to airborne sounds that would result in 
harassment as defined under the MMPA.
    Airborne noise would primarily be an issue for pinnipeds that are 
swimming or hauled out near the project sites within the range of noise 
levels elevated above the airborne acoustic harassment criteria. We 
recognize that pinnipeds in the water could be exposed to airborne 
sound that may result in behavioral harassment when swimming with their 
heads above water. Most likely, airborne sound would cause behavioral 
responses similar to those discussed above in relation to underwater 
sound. For instance, anthropogenic sound could cause hauled-out 
pinnipeds to exhibit changes in their normal behavior, such as 
reduction in vocalizations, or cause them to temporarily abandon the 
area and move further from the source. However, these animals would 
previously have been `taken' because of exposure to underwater sound 
above the behavioral harassment thresholds, which are in all cases 
larger than those associated with airborne sound. Thus, the behavioral 
harassment of these animals is already accounted for in these estimates 
of potential take. Therefore, we do not believe that authorization of 
incidental take resulting from airborne sound for pinnipeds is 
warranted, and airborne sound is not discussed further here.
    Stress Responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral responses, autonomic nervous system responses, 
neuroendocrine responses, or immune responses (e.g., Selye, 1950; 
Moberg, 2000). In many cases, an animal's first and sometimes most 
economical (in terms of energetic costs) response is behavioral 
avoidance of the potential stressor. Autonomic nervous system responses 
to stress typically involve changes in heart rate, blood pressure, and 
gastrointestinal activity. These responses have a relatively short 
duration and may or may not have a significant long-term effect on an 
animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg, 1987; Blecha, 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al., 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and ``distress'' is the cost of 
the response. During a stress response, an animal uses glycogen stores 
that can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This state of 
distress will last until the animal replenishes its energetic reserves 
sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well-studied through 
controlled experiments and for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003; 
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to 
exposure to anthropogenic sounds or other stressors and their effects 
on marine mammals have also been reviewed (Fair and Becker, 2000; 
Romano et al., 2002b) and, more rarely, studied in wild populations 
(e.g., Romano et al., 2002a). For example, Rolland et al. (2012) found 
that noise reduction from reduced ship traffic in the Bay of Fundy was 
associated with decreased stress in North Atlantic right whales. These 
and other studies lead to a reasonable expectation that some marine 
mammals will experience physiological stress responses upon exposure to 
acoustic stressors and that it is possible that some of these would be 
classified as ``distress.'' In addition, any animal experiencing TTS 
would likely also experience stress responses (NRC, 2003), however 
distress is an unlikely result of this project based on observations of 
marine mammals during previous, similar projects in the area.
    Auditory Masking--Sound can disrupt behavior through masking, or 
interfering with, an animal's ability to detect, recognize, or 
discriminate between acoustic signals of interest (e.g., those used for 
intraspecific communication and social interactions, prey detection, 
predator avoidance, navigation) (Richardson et al., 1995; Erbe et al., 
2016). Masking occurs when the receipt of a sound is interfered with by 
another coincident sound at similar frequencies and at similar or 
higher intensity, and may occur whether the sound is natural (e.g., 
snapping shrimp, wind, waves, precipitation) or anthropogenic (e.g., 
shipping, sonar, seismic exploration) in origin. The ability of a noise 
source to mask biologically important sounds depends on the 
characteristics of both the noise source and the signal of interest 
(e.g., signal-to-noise ratio, temporal variability, direction), in 
relation to each other and to an animal's hearing abilities (e.g., 
sensitivity, frequency range, critical ratios, frequency 
discrimination, directional discrimination, age or TTS hearing loss), 
and existing ambient noise and propagation conditions. Masking of 
natural sounds can result when human activities produce high levels of 
background sound at frequencies important to marine mammals. 
Conversely, if the background level of underwater sound is high (e.g., 
on a day with strong wind and high waves), an anthropogenic sound 
source would not be detectable as far away as would be possible under 
quieter conditions and would itself be masked.
    Under certain circumstances, marine mammals experiencing 
significant masking could also be impaired from maximizing their 
performance fitness in survival and reproduction. Therefore, when the 
coincident (masking) sound is man-made, it may be considered harassment 
when disrupting or altering critical behaviors. It is important to 
distinguish TTS and PTS, which persist after the sound exposure, from 
masking, which occurs during the sound exposure. Because masking 
(without resulting in TS) is not associated with abnormal physiological 
function, it is not considered a physiological effect, but rather a 
potential behavioral effect.
    The frequency range of the potentially masking sound is important 
in determining any potential behavioral impacts. For example, low-
frequency signals may have less effect on high-frequency echolocation 
sounds produced by odontocetes but are more likely to affect detection 
of mysticete communication calls and other potentially important 
natural sounds

[[Page 26448]]

such as those produced by surf and some prey species. The masking of 
communication signals by anthropogenic noise may be considered as a 
reduction in the communication space of animals (e.g., Clark et al., 
2009) and may result in energetic or other costs as animals change 
their vocalization behavior (e.g., Miller et al., 2000; Foote et al., 
2004; Parks et al., 2007; Di Iorio and Clark, 2009; Holt et al., 2009). 
Masking can be reduced in situations where the signal and noise come 
from different directions (Richardson et al., 1995), through amplitude 
modulation of the signal, or through other compensatory behaviors 
(Houser and Moore, 2014). Masking can be tested directly in captive 
species (e.g., Erbe, 2008), but in wild populations it must be either 
modeled or inferred from evidence of masking compensation. There are 
few studies addressing real-world masking sounds likely to be 
experienced by marine mammals in the wild (e.g., Branstetter et al., 
2013).
    Masking affects both senders and receivers of acoustic signals and 
can potentially have long-term chronic effects on marine mammals at the 
population level as well as at the individual level. Low-frequency 
ambient sound levels have increased by as much as 20 dB (more than 
three times in terms of SPL) in the world's ocean from pre-industrial 
periods, with most of the increase from distant commercial shipping 
(Hildebrand, 2009). All anthropogenic sound sources, but especially 
chronic and lower-frequency signals (e.g., from vessel traffic), 
contribute to elevated ambient sound levels, thus intensifying masking. 
Many of the Coast Guard facilities are in areas that contain active 
commercial shipping, fishing, cruise ship, and ferry operations, as 
well as numerous recreational and other commercial vessels; therefore, 
background sound levels in the areas are generally already elevated.

Marine Mammal Habitat Effects

    The Coast Guard's construction activities could have localized, 
temporary impacts on marine mammal habitat and their prey by increasing 
in-water sound pressure levels and slightly decreasing water quality. 
Increased noise levels may affect acoustic habitat (see masking 
discussion above) and adversely affect marine mammal prey in the 
vicinity of the project area (see discussion below). During 
construction activities, elevated levels of underwater noise would 
ensonify nearby areas where both fishes and mammals occur and could 
affect foraging success.
    Construction activities are of short duration and would likely have 
temporary impacts on marine mammal habitat through increases in 
underwater and airborne sound.
    In-water pile driving, cutting, and power washing activities would 
also cause short-term effects on water quality due to increased 
turbidity. Local strong currents are anticipated to disburse any 
additional suspended sediments produced by project activities at 
moderate to rapid rates depending on tidal stage. The Coast Guard would 
employ other standard construction best management practices (see 
section 11 in the Coast Guard's application), thereby reducing any 
impacts. Therefore, the impact from increased turbidity levels is 
expected to be discountable.

In-Water Construction Effects on Potential Foraging Habitat

    The area likely impacted by the project is relatively small 
compared to the available habitat in the Gulf of Alaska. For a couple 
of facilities the ensonified area includes BIAs for feeding or 
migration for gray and/or humpback whales as well as critical habitats 
(see above). Kodiak and the distant areas around Cordova are included 
in the area designated as critical habitat for the Mexico DPS of 
humpback whales. Additionally, five haulout sites are located within 20 
nautical miles (37 km) of Base Kodiak, the Seward Moorings, and of the 
Cordova Moorings. The planned activity is not anticipated to have any 
meaningful or lasting impacts to any of the aforementioned habitats of 
biological or critical importance, nor is it anticipated to 
significantly influence the behaviors of marine mammals in these 
habitats. Pile driving, power washing, and DTH may temporarily increase 
turbidity resulting from suspended sediments. Any increases would be 
temporary, localized, and minimal. The Coast Guard must comply with 
state water quality standards during these operations. In general, 
turbidity associated with pile installation is localized to about a 25-
ft (7.6-m) radius around the pile (Everitt et al., 1980). Any pinnipeds 
would be transiting the area and could avoid localized areas of 
turbidity. Therefore, the impact from increased turbidity levels is 
expected to be discountable to marine mammals. Furthermore, pile 
driving at the project sites would not obstruct movements or migration 
of marine mammals.
    Avoidance by potential prey (i.e., fish) of the immediate area due 
to the temporary loss of this foraging habitat is also possible. The 
duration of fish avoidance of this area after pile driving, washing, 
cutting or DTH stops is unknown, but a rapid return to normal 
recruitment, distribution, and behavior is anticipated. Any behavioral 
avoidance by fish of the disturbed area would still leave significantly 
large areas of fish and marine mammal foraging habitat in the nearby 
vicinity.
    The duration of the construction activities is relatively short. 
During each day, construction activities would generally only occur 
during daylight hours, with exceptions at the end of the work day to 
ensure safety of the site and construction personnel. Impacts to 
habitat and prey are expected to be minimal based on the short duration 
of activities and small size of affected areas, and the likelihood that 
the areas that are impacted are not of particular importance to marine 
mammals.
    In-Water Construction Effects on Potential Prey (Fish)--
Construction activities would produce continuous, non-impulsive (i.e., 
vibratory pile driving, DTH) and intermittent impulsive (i.e., impact 
driving and DTH) sounds. Fish utilize the soundscape and components of 
sound in their environment to perform important functions such as 
foraging, predator avoidance, mating, and spawning (e.g., Zelick et 
al., 1999; Fay, 2009). Depending on their hearing anatomy and 
peripheral sensory structures, which vary among species, fishes hear 
sounds using pressure and particle motion sensitivity capabilities and 
detect the motion of surrounding water (Fay et al., 2008). The 
potential effects of noise on fishes depends on the overlapping 
frequency range, distance from the sound source, water depth of 
exposure, and species specific hearing sensitivity, anatomy, and 
physiology. Key impacts to fishes may include behavioral responses, 
hearing damage, barotrauma (pressure-related injuries), and mortality.
    SPLs of sufficient strength have been known to cause injury to fish 
and fish mortality (Dahl et al., 2020). However, in most fish species, 
hair cells in the ear continuously regenerate and loss of auditory 
function likely is restored when damaged cells are replaced with new 
cells. Halvorsen et al. (2012a) showed that a TTS of 4-6 dB was 
recoverable within 24 hours for one species. Non-auditory injuries 
caused by barotrauma can range from slight to severe and can cause 
death, and is most likely for fish with swim bladders. Barotrauma 
injuries have been documented during controlled exposure to explosions 
and during impact pile driving; however, the relationships between 
severity of injury and location

[[Page 26449]]

of the fish relative to the sound are not well understood (Halvorsen et 
al., 2012b; Casper et al., 2013; Dahl et al., 2020).
    Fish react to sounds that are especially strong and/or intermittent 
low-frequency sounds. Short duration, sharp sounds can cause overt or 
subtle changes in fish behavior and local distribution. Hastings and 
Popper (2005) identified several studies that suggest fish may relocate 
to avoid certain areas of sound energy. Additional studies have 
documented effects of pile driving on fish (e.g., Scholik and Yan, 
2001, 2002; Popper and Hastings, 2009). Impulsive sounds might affect 
the distribution and behavior of some fishes, potentially impacting 
foraging opportunities or increasing energetic costs (e.g., Fewtrell 
and McCauley, 2012; Pearson et al., 1992; Skalski et al., 1992; 
Santulli et al., 1999; Paxton et al., 2017). However, some studies have 
shown no or slight reaction to impulse sounds (e.g., Pena et al., 2013; 
Wardle et al., 2001; Jorgenson and Gyselman, 2009; Cott et al., 2012). 
More commonly, though, the impacts of noise on fish are temporary and 
include changes to behavior that return to baseline shortly after the 
noise-producing activity stops.
    The most likely impact to fish from pile driving and DTH activities 
at the project areas would be temporary behavioral avoidance of the 
area. The duration of fish avoidance of the area after pile driving 
stops is unknown, but a rapid return to normal recruitment, 
distribution, and behavior is anticipated. There are times of known 
seasonal marine mammal foraging in the area of the facilities around 
fish processing/hatchery infrastructure or when fish are congregating, 
but the impacted areas are a small portion of the total foraging 
habitat available in the region. In general, impacts to marine mammal 
prey species are expected to be minor and temporary due to the short 
timeframe of the project and the small project footprint.
    Construction activities, in the form of increased turbidity, have 
the potential to adversely affect forage fish and juvenile salmonid 
out-migratory routes in the project area. Both herring and salmon form 
a significant prey base for Steller sea lions, herring is a primary 
prey species of humpback whales, and both herring and salmon are 
components of the diet of many other marine mammal species that occur 
in the project area. Increased turbidity is expected to occur in the 
immediate vicinity (on the order of 25 ft or less) of construction 
activities. However, suspended sediments and particulates are expected 
to dissipate quickly within a single tidal cycle. Given the limited 
area affected and high tidal dilution rates any effects on forage fish 
and salmon are expected to be minor or negligible. In addition, best 
management practices would be in effect, which would limit the extent 
of turbidity to the immediate project area. Finally, exposure to turbid 
waters from construction activities is not expected to be different 
from the current exposure; fish and marine mammals in the region are 
routinely exposed to substantial levels of suspended sediment from 
glacial sources.
    In-water work windows have been established to minimize the impacts 
of the proposed activity on sensitive life stages essential fish that 
are considered prey species for many marine mammals. Table 1 notes when 
periods of in-water work may not occur and at which facility.
    In summary, given the short daily duration of sound associated with 
individual pile driving and DTH events and the relatively small areas 
being affected, pile driving and DTH activities associated with the 
proposed action are not likely to have a permanent, adverse effect on 
any fish habitat, or populations of fish species. Thus, we conclude 
that impacts of the specified activity are not likely to have more than 
short-term adverse effects on any prey habitat or populations of prey 
species. Further, any impacts to marine mammal habitat are not expected 
to result in significant or long-term consequences for individual 
marine mammals, or to contribute to adverse impacts on their 
populations.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization, which will inform both NMFS' consideration 
of ``small numbers'' and the negligible impact determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as: any act of 
pursuit, torment, or annoyance which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would be by Level A or Level B harassment only, in 
the form of disruption of behavioral patterns for individual marine 
mammals resulting from exposure to the acoustic sources. Based on the 
nature of the activity, no serious injury or mortality is anticipated 
or proposed to be authorized for this activity. Below we describe how 
the take is estimated.
    Generally speaking, we estimate take by considering: (1) acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    NMFS recommends the use of acoustic thresholds that identify the 
received level of underwater sound above which exposed marine mammals 
would be reasonably expected to be behaviorally harassed (equated to 
Level B harassment) or to incur PTS of some degree (equated to Level A 
harassment).
    Level B Harassment--Though significantly driven by received level, 
the onset of behavioral disturbance from anthropogenic noise exposure 
is also informed to varying degrees by other factors related to the 
source (e.g., frequency, predictability, duty cycle), the environment 
(e.g., bathymetry), and the receiving animals (hearing, motivation, 
experience, demography, behavioral context) and can be difficult to 
predict (Southall et al., 2007, Ellison et al., 2012). Based on what 
the available science indicates and the practical need to use a 
threshold based on a factor that is both predictable and measurable for 
most activities, NMFS uses a generalized acoustic threshold based on 
received level to estimate the onset of behavioral harassment. NMFS 
predicts that marine mammals are likely to be behaviorally harassed in 
a manner we consider Level B harassment when exposed to underwater 
anthropogenic noise above received levels of 120 dB referenced to 1 
micropascal (re 1 [mu]Pa) root mean square (rms) for continuous (e.g., 
vibratory pile-driving, DTH) and

[[Page 26450]]

above 160 dB re 1 [mu]Pa (rms) for non-explosive impulsive, 
intermittent (e.g., impact driving, DTH) sources.
    The Coast Guard's proposed activity includes the use of continuous 
(vibratory, DTH) and impulsive (impact pile driving and DTH) sources, 
and therefore the 120 and 160 dB re 1 [mu]Pa (rms) thresholds, 
respectively, are applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The Coast Guard's proposed activity 
includes the use of impulsive (impact pile driving and DTH) and non-
impulsive (vibratory, DTH) sources.
    These thresholds are provided in the table below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 6--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                     PTS onset acoustic thresholds * (received level)
             Hearing Group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW)(Underwater).....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. In this table, thresholds are abbreviated to reflect American
  National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
  incorporating frequency weighting, which is not the intent for the Technical Guidance. Hence, the subscript
  ``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
  generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
  the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
  and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
  be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
  it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into estimating the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
    The sound field in the project area is the existing background 
noise plus additional construction noise from the proposed project. 
Marine mammals are expected to be affected via sound generated by the 
primary components of the project (i.e., impact pile driving, vibratory 
pile driving, vibratory pile removal, and DTH).
    The actual durations of each installation method vary depending on 
the type and size of the pile. In order to calculate distances to the 
Level A harassment and Level B harassment sound thresholds for piles of 
various sizes and equipment being used in this project, NMFS used 
acoustic monitoring data from other locations to develop source levels 
(Table 7). Note that piles and holes of differing sizes have different 
sound source levels (SSLs). For simplicity and to be precautionary we 
analyze the largest pile diameter of each type (e.g., 24-inch diameter) 
even though it is possible at some locations in some situations smaller 
pile diameters may be used or be removed.

                      Table 7--Sound Source Levels
------------------------------------------------------------------------
                                  Sound source level
      Method and pile type         at 10 meters (dB)   Literature source
------------------------------------------------------------------------
Timber Vibratory................  152 RMS...........  Greenbusch Group
                                                       2018.
24-inch Steel Pipe Vibratory....  162 RMS...........  Laughlin 2010.
Timber Impact...................  170 RMS, 160 SEL,   CALTRANS 2015.
                                   180 Pk.
Composite impact................  153 RMS, 145 SEL..  CALTRANS 2020.
24-inch Steel Pipe Impact.......  190 RMS, 177 SEL,   CALTRANS 2015.
                                   203 Pk.
24-inch Concrete Impact.........  170 RMS, 159 SEL,   Mukilteo Terminal
                                   184 Pk.             (WSDOT 2020).
DTH Non-impulsive component.....  167 RMS...........  Heyvaert & Reyff
                                                       2021.
24-inch DTH Impulsive component.  159 SEL, 184 dB Pk  Heyvaert & Reyff
                                                       2021.
------------------------------------------------------------------------
Note: It is assumed that noise levels during pile installation and
  removal are similar. SEL = single strike sound exposure level; peak =
  peak sound level; RMS = root mean square.

Level B Harassment Zones

    Transmission loss (TL) is the decrease in acoustic intensity as an 
acoustic pressure wave propagates out from a source. TL parameters vary 
with frequency, temperature, sea conditions, current, source and 
receiver depth, water depth, water chemistry, and bottom composition 
and topography. The general formula for underwater TL is:

TL = B * Log10 (R1/R2),

where


[[Page 26451]]


TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R1 = the distance of the modeled SPL from the driven pile, and
R2 = the distance from the driven pile of the initial measurement

    The recommended TL coefficient for most nearshore environments is 
the practical spreading value of 15. This value results in an expected 
propagation environment that would lie between spherical and 
cylindrical spreading loss conditions, which is the most appropriate 
assumption for the Coast Guard's proposed activity.
    Using the practical spreading model, the Coast Guard determined 
underwater noise would fall below the behavioral effects thresholds of 
120 dB rms or 160 dB rms for marine mammals at a maximum radial 
distances from 46 m for impact driving of timber or concrete piles to 
13,594 m for DTH (Table 8). These distances determine the maximum Level 
B harassment zones for the project. It should be noted that based on 
the geography of many of the sites, sound will not reach the full 
distance of the Level B harassment isopleth. Generally, due to 
interaction with land, only a portion of the possible area is 
ensonified.

      Table 8--Calculated Distances to Level B Harassment Isopleths
------------------------------------------------------------------------
                                                              Level B
                  Method and pile type                     isopleth  (m)
------------------------------------------------------------------------
Timber Vibratory........................................           1,359
24-inch Steel Pipe Vibratory............................           6,310
Timber Impact...........................................              46
Composite Impact........................................               3
24-inch Steel Pipe Impact...............................            1000
24-inch Concrete Impact.................................              46
DTH.....................................................          13,594
------------------------------------------------------------------------

Level A Harassment Zones

    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of take by Level A harassment. However, these tools offer 
the best way to predict appropriate isopleths when more sophisticated 
three dimensional modeling methods are not available, and NMFS 
continues to develop ways to quantitatively refine these tools, and 
will qualitatively address the output where appropriate. For stationary 
sources such as pile driving or DTH, NMFS User Spreadsheet predicts the 
closest distance at which, if a marine mammal remained at that distance 
the whole duration of the activity, it would not incur PTS.
    Inputs used in the User Spreadsheet (Table 9), and the resulting 
isopleths are reported below (Table 10). We analyzed scenarios with up 
to five piles per day to account for maximum possible production rates. 
Level A harassment thresholds for impulsive sound sources (impact pile 
driving and DTH) are defined for both SELcum and Peak SPL, with the 
threshold that results in the largest modeled isopleth for each marine 
mammal hearing group used to establish the Level A harassment isopleth. 
In this analysis, Level A harassment isopleths based on SELcum were 
always larger than those based on Peak SPL.

                    Table 9--Inputs of Pile Driving and DTH Activity Used in User Spreadsheet
----------------------------------------------------------------------------------------------------------------
                                                                                     Duration
                                                                     Weighting       (minutes;
                      Method and pile type                            factor       vibratory) or   Piles per day
                                                                    adjustment      strikes per
                                                                                  pile  (impact)
----------------------------------------------------------------------------------------------------------------
Timber Vibratory................................................             2.5              50               5
24-inch Steel Pipe Vibratory....................................             2.5              10               5
Timber Impact...................................................               2             100               5
Composite Impact................................................               2             120               5
24-inch Steel Pipe Impact.......................................               2             400               1
24-inch Concrete Impact.........................................               2             184               5
24-inch DTH.....................................................               2              60               2
----------------------------------------------------------------------------------------------------------------
Note: Data for all equipment types were for transmission loss of 15*log(r) and distance of source level
  measurements was 10 meters.

    The above input scenarios lead to a PTS isopleth distance (Level A 
harassment threshold) of 0 to 517.1 m, depending on the marine mammal 
hearing group and scenario (Table 9).

Table 10--Calculated Distances to Level A Harassment Isopleths (m) During Pile Installation and Removal for Each
                                                  Hearing Group
----------------------------------------------------------------------------------------------------------------
                                                                       High
      Method and pile type         Low frequency   Mid frequency     frequency        Phocid          Otariid
----------------------------------------------------------------------------------------------------------------
Timber Vibratory................             1.5             0.1             2.2             0.9             0.1
24-inch Steel Pipe Vibratory....             7.1             0.6            10.4             4.3             0.3
Timber Impact...................            18.4             0.7            21.9             9.9             0.7
Composite Impact................             2.1             0.1             2.5             1.1             0.1
24-inch Steel Pipe Impact.......           215.8             7.7           257.1           115.5             8.4
24-inch Concrete Impact.........            27.7               1            33.0            14.8             1.1
24-inch DTH.....................           434.1            15.4           517.1           232.2            16.9
----------------------------------------------------------------------------------------------------------------
Note: a minimum 20-m shutdown zone, as proposed by the Coast Guard, will be implemented for all species and
  activity types to prevent direct injury of marine mammals.


[[Page 26452]]

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. Here we describe how the information provided above is 
brought together to produce a quantitative take estimate.
    Available information regarding marine mammal occurrence and 
abundance in the vicinity of the eight facilities includes monitoring 
data from the NMFS Alaska Regional Office, prior incidental take 
authorizations, and ESA consultations on additional projects (Table 
11). When local density information is not available, data aggregated 
in the Navy's Marine Mammal Species Density Database (U.S. Navy, 2019, 
2020) for the Gulf of Alaska or Northwest Testing and Training areas 
(Table 12) or nearby proxies from the monitoring data are used; 
whichever gives the most precautionary take estimate was chosen.

Table 11--Marine Mammal Occurrence Data (per day) From Prior Projects

BILLING CODE 3510-22-P
[GRAPHIC] [TIFF OMITTED] TP28AP23.004

    Note: NA indicates that occurrence data was not used for that 
species and site combination. Density data for species/site 
combinations listed as NA in this table are shown in Table 12.

[[Page 26453]]



            Table 12--Marine Mammal Densities From Navy Data
------------------------------------------------------------------------
                                                        Gulf of Alaska/
                                   Southeast Alaska     Prince William
              Stock               facilities species   Sound facilities
                                      density  (#/    species density (#/
                                     km\2\) 1 2 3        km\2\) 3 4 5
------------------------------------------------------------------------
Gray whale......................               0.016               0.048
Humpback whale Central North                   0.002               0.093
 Pacific........................
Humpback Whale Western North                     N/A               0.093
 Pacific \6\....................
Fin whale.......................              0.0001               0.068
Minke whale.....................               0.001               0.006
Killer whale (General)..........                 N/A               0.005
Killer whale Resident...........               0.035                 N/A
Killer whale Transient..........               0.006                 N/A
Pacific white-sided dolphin.....               0.085               0.020
Dall's porpoise.................               0.121               0.218
Harbor porpoise.................               0.010               0.455
California sea lion \7\.........               0.025                   0
Northern fur seal...............               0.276               0.090
Steller sea lion................               0.316               0.068
Harbor seal.....................               1.727               0.169
------------------------------------------------------------------------
\1\ Facilities including Ketchikan, Sitka, Juneau, and Petersburg.
\2\ Southeast Alaska density values generally from Western Behm Canal
  values reported in U.S. Navy (2020).
\3\ Where species density values reported in the U.S. Navy (2020) and
  U.S. Navy (2021) vary by time of year, the greatest value is presented
  here as a conservative estimate.
\4\ Facilities including Kodiak, Seward, Valdez, and Cordova.
\5\ Gulf of Alaska/Prince William Sound species density values generally
  from inshore or within the 500-1000 m isobath values reported in U.S.
  Navy (2021).
\6\ The range for the Western North Pacific stock of humpback whales
  does not extend to Southeast Alaska.
\7\ U.S. Navy 2020 density values for California sea lion do not include
  Western Behm Canal and the value used here is from the San Juan
  Islands, the next closest zone to the project area where a density
  value is available.

    The data on abundance and occurrence from prior projects is derived 
from the following projects: (1) Kodiak--PSO monitoring reports from 
dock repair projects in 2018 and 2020 (NMFS Alaska Region). (2) Sitka--
Data are from the Old Sitka Dock project (86 FR 22392, April 28, 2021). 
(3) Ketchikan--Data are from the Tongass Narrows project (85 FR 673, 
January 7, 2020) and other projects in preparation in the area. (4) 
Valdez--Data are from monitoring for an oil spill response in late 
April and early May 2020 (NMFS Alaska Region). (5) Juneau--Data are 
from the Erickson Dock project (84 FR 65360, November 27, 2019) and the 
Juneau Waterfront Improvement Project (85 FR 18562, April 2, 2020). (6) 
Seward--An IHA application for the Seward Passenger Terminal project 
recently received by NMFS included information resulting from 
consultation with the Alaska SeaLife Center, the Kenai Fjords NPS, 
local whale watching companies, and scientific literature to estimate 
the occurrence of marine mammals in Seward.
    To quantitatively assess exposure of marine mammals to noise from 
pile driving and drilling activities when density estimates are most 
appropriate we used the density estimate and the annual anticipated 
number of work days for each activity (Table 2) at each facility to 
determine the number of animals potentially harassed on any one day of 
activity. The calculation is:

Exposure estimate = Density x harassment area x maximum days of 
activity

    For example, exposure estimates at the Ketchikan site for gray 
whales were calculated by first finding the product of the SE Alaska 
species density (0.0155 animals/km\2\), the ensonified area for the 
activity (e.g., 1.45 km\2\ for vibratory pile driving of timber piles), 
for the anticipated number of days for that activity each year (10 
days/year). After finding the product for each activity for each year, 
the values were summed to find the total number of takes for that 
species across all 5 years. This method was used for all species for 
which local occurrence data were not available.
    When occurrence data from prior projects are the most appropriate 
data for exposure estimation, we used the occurrence estimate (number/
unit of time) and the maximum work days (converted to the appropriate 
unit of time as needed) per year (Table 2) at each facility to 
determine the number of animals potentially exposed to an activity. The 
calculation is:

Exposure estimate = Occurrence/time x time of activity

    And these values are then summed across activity/pile types.
    When exposure estimates from density data are used for sites with 
no local occurrence data and the exposure estimate is less than a 
typical group size, we increase the estimated take based on that group 
size to account for the possibility a single group entering the project 
area would exceed authorized take. Table 13 shows the source of data 
used in exposure estimates.
    The size of the Level B harassment zones for each facility and 
activity are in Table 14. Level A harassment take is only proposed for 
the activities creating the largest Level A harassment zones: DTH and 
impact driving of steel pipe piles (see Figures 6-2 through Figure 6-9 
in the Coast Guard's application), and for species that would be 
difficult for observers to detect within large, unconfined zones: high 
frequency cetaceans and phocid pinnipeds. The topography of sites and 
facilities in Seward, Juneau, Sitka, and Petersburg are restricted such 
that noise would be confined to a small area or basin, and PSOs would 
be able to observe any marine mammals approaching the activity are and 
Level A shutdown zone with enough warning that work could be stopped 
before a take by Level A harassment would occur. The facilities at the 
remaining four sites (Kodiak, Ketchikan, Valdez, and Cordova) are less 
confined, and PSOs may be unable

[[Page 26454]]

to observe cryptic species at the calculated isopleths. Therefore, we 
conservatively propose small numbers of take by Level A harassment for 
high frequency cetaceans and phocid pinnipeds at these sites.

Table 13--Source of Data Used To Estimate Exposure for Each Species or 
Stock and Facility
[GRAPHIC] [TIFF OMITTED] TP28AP23.005

    Abbreviations for source data are: N--Navy density data, Ke--
Ketchikan, Sit--Sitka, Sew--Seward, J--Juneau, V--Valdez, Ko--Kodiak, 
G--estimate rounded up to 1 group *--Not applicable (no take).

[[Page 26455]]



                              Table 14--Level B Harassment Areas at Each Facility (km\2\) for Each Method and/or Pile Type
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Timber           Steel                       Composite \1\
                        Facility                             vibratory       vibratory     Timber impact      impact       Steel impact         DTH
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kodiak..................................................             1.3            4.51           0.006               0            1.03            4.51
Sitka...................................................            0.87            5.67           0.007               0            0.56  ..............
Ketchikan...............................................            1.45            7.29           0.004               0            1.06            10.1
Valdez..................................................            2.62           40.21           0.007               0            1.43  ..............
Cordova.................................................  ..............           23.42  ..............  ..............            1.57  ..............
Juneau..................................................            1.62              NA           0.003               0              NA  ..............
Petersburg..............................................            1.63            2.89           0.006               0            1.33  ..............
Seward..................................................  ..............            0.24  ..............  ..............            0.24  ..............
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Composite Level B harassment zone (3 m) is completely encompassed by the 20 m shutdown zone proposed by Coast Guard.

    The calculated Level B harassment takes using the above data for 
each year are in Table 15 and for each facility over the course of the 
proposed rule are in Table 16. See Tables 6-14 through 6-21 in the 
application and the supplemental memo (composite piles) for detailed 
calculations of estimated take for each pile type and activity at each 
facility. The calculated Level A harassment takes using the above data 
for each year are in Table 17 and for each facility over the course of 
the proposed rule are in Table 18.
    Table 19 summarizes Level A and Level B harassment take proposed to 
be authorized for the project as well as the percentage of each stock 
expected to be taken in the year with the maximum annual takes over the 
course of the project.

                         Table 15--Proposed Level B Harassment Take in Each of the Five Years and in Total for the Proposed Rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
                          Stock                               Year 1          Year 2          Year 3          Year 4          Year 5           Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray whale..............................................               8               8               8               8               8              40
Humpback whale *........................................             160             174             164             160             160             818
Fin whale...............................................              13              23              13              13              13              75
Minke whale.............................................               5               6               5               5               5              25
Killer whale *..........................................             103             344             144             103             103             797
Pacific white-sided dolphin.............................             215             297             337             215             215           1,379
Dall's porpoise.........................................             114             147             115             114             114             604
Harbor porpoise Southeast Alaska........................              72              72              72              72              72             360
Harbor porpoise Gulf of Alaska..........................              47             115              48              47              47             304
California sea lion.....................................              10              10              10              10              10              50
Northern fur seal.......................................               9              23             131               9               9             181
Steller sea lion Eastern................................             425             425             425             425             425           2,125
Steller sea lion Western................................              24              34              32              24              24             138
Harbor seal Prince William Sound........................             148             442             344             148             148           1,230
Harbor seal Lynn Canal/Stephens Passage.................             860             860             860             860             860           4,300
Harbor seal Sitka/Chatham Straight......................             230             230             230             230             230           1,150
Harbor seal Clarence Strait.............................             412             412             412             412             412           2,060
Harbor seal South Kodiak................................              17              17              17              17              17              85
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Stocks of killer whales and humpback whales cannot generally be identified in the field so total proposed take is listed at species level only.


[[Page 26456]]

Table 16--Proposed Level B Harassment Take for Each Facility
[GRAPHIC] [TIFF OMITTED] TP28AP23.006


[[Page 26457]]


[GRAPHIC] [TIFF OMITTED] TP28AP23.007


                               Table 17--Proposed Level A Harassment Take in Each Year and in Total for the Proposed Rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
                          Stock                                  1               2               3               4               5             Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dall's porpoise Alaska..................................              86              98              86              86              86             442
Harbor porpoise Southeast Alaska........................              20              20              20              20              20             100
Harbor porpoise Gulf of Alaska..........................              55              85              55              55              55             305
Harbor seal South Kodiak................................              20              20              20              20              20             100
Harbor seal Clarence Strait.............................              20              20              20              20              20             100
--------------------------------------------------------------------------------------------------------------------------------------------------------

Table 18--Proposed Level A Harassment Take for Each Facility of the 
Proposed Rule
[GRAPHIC] [TIFF OMITTED] TP28AP23.008

    [Define ``NA''].
BILLING CODE 3510-22-C

[[Page 26458]]



  Table 19--Proposed Level A and Level B Harassment Take and Percent of Stock for the Highest Annual Estimated
                                              Takes of the Project
----------------------------------------------------------------------------------------------------------------
                                                                                                    Percent of
                      Stock                           Level A         Level B          Total           stock
----------------------------------------------------------------------------------------------------------------
Gray whale Eastern North Pacific................               0               8               8            0.03
Humpback whale Central North Pacific Humpback                  0             174             174         \a\ 1.7
 whale Western North Pacific....................                                                         \a\ 0.3
Fin whale Northeast Pacific.....................               0              23              23             N/A
Minke whale Alaska..............................               0               6               6             N/A
Killer whale Alaska Resident....................               0             344             344       \a\ 14.65
Killer whale Gulf of Alaska, Aleutian Islands,    ..............  ..............  ..............       \a\ 13.95
 Bearing Sea Transient..........................
Killer whale Northern Resident..................  ..............  ..............  ..............        \a\ 3.23
Killer whale AT1 Transient \b\..................  ..............  ..............  ..............           a b 0
Killer whale West Coast Transient...............  ..............  ..............  ..............        \a\ 3.23
Pacific white-sided dolphin North Pacific.......               0             397             397            1.48
Dall's porpoise Alaska..........................              98             147             245             N/A
Harbor porpoise Southeast Alaska................              20              72              92            8.70
Harbor porpoise Gulf of Alaska..................              85             115             245            0.64
California sea lion U.S.........................               0              10              10            0.00
Northern fur seal Eastern Pacific...............               0             131             131            0.02
Steller sea lion Eastern........................               0             425             425            0.98
Steller sea lion Western........................               0              34              34            0.06
Harbor seal Prince William Sound................               0             442             442            1.06
Harbor seal Lynn Canal/Stephens Passage.........               0             860             860            7.25
Harbor seal Sitka/Chatham Straight..............               0             230             230            1.94
Harbor seal Clarence Strait.....................              20             412             432            1.74
Harbor seal South Kodiak........................              20              17              37            0.17
----------------------------------------------------------------------------------------------------------------
\a\ Percent of stock impacted for humpback and killer whales was estimated assuming each stock is taken in
  proportion to its population size at any given facility site from the total take (E.g., for killer whales at
  Kodiak, the Alaska Resident and Gulf of Alaska stocks are the only stocks present. Of these, the Alaska
  Resident stock represents approximately 80% of the available animals, and GOA represents approximately 20%,
  giving 4 total Alaska Resident killer whale takes over the 5 years, and 1 GOA killer whale take. This division
  was replicated for each site for all present stocks. Takes were then calculated for each site based on the
  proportional representation of available stocks. Total takes for each stock are shown as a percentage of the
  stock size.)
\b\ AT1 Transient killer whales have the potential to be present in the Seward, Valdez, and Cordova, however we
  do not expect any of the seven individuals to approach the project sites, therefore no take is expected to
  occur for this stock and none is proposed for authorization.

Proposed Mitigation

    Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the 
permissible methods of taking pursuant to such activity, and other 
means of effecting the least practicable adverse impact on such species 
or stock and its habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance, and on the 
availability of such species or stock for taking for certain 
subsistence uses (``least practicable adverse impact''). NMFS does not 
have a regulatory definition for ``least practicable adverse impact.'' 
NMFS regulations require applicants for incidental take authorizations 
to include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat, as 
well as subsistence uses. This considers the nature of the potential 
adverse impact being mitigated (likelihood, scope, range). It further 
considers the likelihood that the measure will be effective if 
implemented (probability of accomplishing the mitigating result if 
implemented as planned), the likelihood of effective implementation 
(probability implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost and impact on 
operations.
    The mitigation strategies described below largely follow those 
required and successfully implemented under previous incidental take 
authorizations issued in association with similar construction 
activities. Measurements from similar pile driving events were coupled 
with practical spreading loss and other relevant information to 
estimate harassment zones (see Estimated Take); these zones were used 
to develop mitigation measures for DTH and pile driving activities at 
the eight facilities. Background discussion related to underwater sound 
concepts and terminology is provided in the section on Description of 
Sound Sources, earlier in this preamble.
    The following mitigation measures are proposed:
     Avoid direct physical interaction with marine mammals 
during construction activity. If a marine mammal comes within 20 m of 
such activity, operations must cease and vessels must reduce speed to 
the minimum level required to maintain steerage and safe working 
conditions. The Coast Guard has elected to establish a minimum shutdown 
zone size of 20 m, larger than NMFS' typical requirement of a minimum 
10 m shutdown zone;
     Conduct training between construction supervisors and 
crews and the marine mammal monitoring team and relevant Coast Guard 
staff prior to the start of all pile driving, cutting or power washing 
activity and when new personnel join the work, so that 
responsibilities, communication

[[Page 26459]]

procedures, monitoring protocols, and operational procedures are 
clearly understood;
     DTH and pile driving activity must be halted upon 
observation of either a species for which incidental take is not 
authorized or a species for which incidental take has been authorized 
but the authorized number of takes has been met, entering or within the 
harassment zone;
     The Coast Guard will establish and implement a minimum 
shutdown zone of 20 m during all pile driving and removal activity, as 
well as the larger zones indicated in Table 20. The purpose of a 
shutdown zone is generally to define an area within which shutdown of 
the activity would occur upon sighting of a marine mammal (or in 
anticipation of an animal entering the defined area). Shutdown zones 
typically vary based on the activity type and marine mammal hearing 
group. The Coast Guard has elected to establish a minimum shutdown zone 
size of 20 m, larger than NMFS' typical requirement of a minimum 10 m 
shutdown zone;
     Employ PSOs and establish monitoring locations as 
described in the application, any issued LOA and the Marine Mammal 
Monitoring Plan. The Holder must monitor the project area to the 
maximum extent possible based on the required number of PSOs, required 
monitoring locations, and environmental conditions. For all DTH and 
pile driving at least one PSO must be used. The PSO will be stationed 
as close to the activity as possible;
     The placement of the PSOs during all DTH and pile driving 
activities will ensure that the entire shutdown zone is visible during 
pile installation. Should environmental conditions deteriorate such 
that marine mammals within the entire shutdown zone will not be visible 
(e.g., fog, heavy rain), pile driving must be delayed until the PSO is 
confident marine mammals within the shutdown zone could be detected;
     Monitoring must take place from 30 minutes prior to 
initiation of DTH and pile driving activity through 30 minutes post-
completion of DTH and pile driving activity. Pre-start clearance 
monitoring must be conducted during periods of visibility sufficient 
for the lead PSO to determine the shutdown zones clear of marine 
mammals. DTH and pile driving may commence following 30 minutes of 
observation when the determination is made;
     If DTH or pile driving is delayed or halted due to the 
presence of a marine mammal, the activity may not commence or resume 
until either the animal has voluntarily exited and been visually 
confirmed beyond the shutdown zone or 15 minutes have passed without 
re-detection of the animal;
     The Coast Guard must use soft start techniques prior to 
beginning impact pile driving. Soft start requires contractors to 
provide an initial set of three strikes at reduced energy, followed by 
a 30-second waiting period, then two subsequent reduced-energy strike 
sets. A soft start must be implemented at the start of each day's 
impact pile driving and at any time following cessation of impact pile 
driving for a period of 30 minutes or longer;
     As described previously, the Coast Guard would adhere to 
in-water work windows designed for the protection of fishes and marine 
mammals under other permitting requirements;
     The Coast Guard has volunteered that in-water construction 
activities will occur only during civil daylight hours; and
     Pile driving activity must be halted upon observation of 
either a species for which incidental take is not authorized or a 
species for which incidental take has been authorized but the 
authorized number of takes has been met, entering or within the largest 
applicable harassment zone.

                           Table 20--Shutdown Zones (m) for Each Pile Type and Method
----------------------------------------------------------------------------------------------------------------
                                                                       High
      Method and pile type        Low  frequency  Mid  frequency     frequency        Phocid          Otariid
                                      cetacean        cetacean       cetacean
----------------------------------------------------------------------------------------------------------------
Timber Vibratory................              20              20              20              20              20
24-inch Steel Pipe Vibratory....              20              20              20              20              20
Timber Impact...................              20              20              30              20              20
Composite Impact................              20              20              20              20              20
24-inch Steel Pipe Impact.......             220              20             260             120              20
24-inch Concrete Impact.........              30              20              40              20              20
24-inch DTH.....................             440              20             520             240              20
----------------------------------------------------------------------------------------------------------------

    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance, and on the 
availability of such species or stock for subsistence uses.

Proposed Monitoring and Reporting

    In order to issue an LOA for an activity, section 101(a)(5)(A) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of the authorized taking. The MMPA 
implementing regulations at 50 CFR 216.104(a)(13) indicate that 
requests for authorizations must include the suggested means of 
accomplishing the necessary monitoring and reporting that will result 
in increased knowledge of the species and of the level of taking or 
impacts on populations of marine mammals that are expected to be 
present in the proposed action area. Effective reporting is critical 
both to compliance as well as ensuring that the most value is obtained 
from the required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density).
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving, or feeding areas).
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or

[[Page 26460]]

cumulative), other stressors, or cumulative impacts from multiple 
stressors.
     How anticipated responses to stressors impact either: (1) 
long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks.
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or important physical components of marine 
mammal habitat).
     Mitigation and monitoring effectiveness.

Visual Monitoring

     Monitoring must be conducted by qualified, NMFS-approved 
PSOs, in accordance with the following: PSOs must be independent (i.e., 
not construction personnel) and have no other assigned tasks during 
monitoring periods. At least one PSO must have prior experience 
performing the duties of a PSO during construction activity pursuant to 
a NMFS-issued incidental take authorization. Other PSOs may substitute 
other relevant experience, education (degree in biological science or 
related field), or training. PSOs must be approved by NMFS prior to 
beginning any activity subject to these regulations.
     PSOs must record all observations of marine mammals as 
described in any issued LOA and the NMFS-approved Marine Mammal 
Monitoring Plan, regardless of distance from the pile being driven. 
PSOs shall document any behavioral reactions in concert with distance 
from piles being driven or removed;
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary;
     The Coast Guard must establish the following monitoring 
locations. For all pile driving activities, a minimum of one PSO must 
be assigned to the active pile driving location to monitor the shutdown 
zones and as much of the Level B harassment zones as possible. Proposed 
monitoring locations are shown in Figures 6-1 through 6-41 of the 
application and summarized in Table 21. The number of PSOs required at 
each facility is dependent upon the size of the Level B harassment area 
as well as the topography of the activity site and a PSO's ability to 
observe the estimated Level A harassment area for the particular 
activity.

 Table 21--Summary of Protected Species Observer (PSO) Coverage at Each
                                Facility
------------------------------------------------------------------------
                                                          Maximum number
                        Facility                              of PSOs
------------------------------------------------------------------------
Kodiak..................................................               2
Sitka...................................................               5
Ketchikan...............................................               5
Valdez..................................................               3
Cordova.................................................               3
Juneau..................................................               3
Petersburg..............................................               3
Seward..................................................               2
------------------------------------------------------------------------

Reporting

    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving activities, or 60 
days prior to a requested date of issuance of any future LOAs for 
projects at the same location, whichever comes first. The report will 
include an overall description of work completed, a narrative regarding 
marine mammal sightings, and associated PSO data sheets. Specifically, 
the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring.
     Construction activities occurring during each daily 
observation period, including the number and type of piles driven or 
removed and by what method (i.e., impact or cutting) and the total 
equipment duration for cutting for each pile or total number of strikes 
for each pile (impact driving, DTH).
     PSO locations during marine mammal monitoring.
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
     Upon observation of a marine mammal, the following 
information: name of PSO who sighted the animal(s), and PSO location 
and activity at time of sighting; time of sighting; identification of 
the animal(s) (e.g., genus/species, lowest possible taxonomic level, or 
unidentified), PSO confidence in identification, and the composition of 
the group if there is a mix of species; distance and bearing of each 
marine mammal observed relative to the pile being driven for each 
sighting (if pile driving was occurring at time of sighting); Estimated 
number of animals (min/max/best estimate); estimated number of animals 
by cohort (adults, juveniles, neonates, group composition, etc.); 
animal's closest point of approach and estimated time spent within the 
harassment zone; and description of any marine mammal behavioral 
observations (e.g., observed behaviors such as feeding or traveling), 
including an assessment of behavioral responses thought to have 
resulted from the activity (e.g., no response or changes in behavioral 
state such as ceasing feeding, changing direction, flushing, or 
breaching);
     Number of marine mammals detected within the harassment 
zones, by species.
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.

Reporting Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the LOA-holder must 
immediately cease the specified activities and report the incident to 
the Office of Protected Resources (OPR) ([email protected]), NMFS and to Alaska Regional Stranding Coordinator as 
soon as feasible. If the death or injury was likely caused by the 
specified activity, the Coast Guard must immediately cease the 
specified activities until NMFS is able to review the circumstances of 
the incident and determine what, if any, additional measures are 
appropriate to ensure compliance with the terms of the LOA

[[Page 26461]]

and regulations. The LOA-holder must not resume their activities until 
notified by NMFS. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS' implementing 
regulations (54 FR 40338, September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, ongoing sources of human-caused mortality, or 
ambient noise levels).
    DTH and pile driving activities associated with the maintenance 
projects, as described previously, have the potential to disturb or 
displace marine mammals. Specifically, the specified activities may 
result in take, in the form of Level B harassment (behavioral 
disturbance) only for all species other than the harbor porpoise, 
harbor seal, and Dall's porpoise from underwater sounds generated from 
DTH and pile driving. Potential takes could occur if individual marine 
mammals are present in the ensonified zone when DTH or pile driving is 
happening.
    No serious injury or mortality would be expected even in the 
absence of the proposed mitigation measures. For all species other than 
the harbor seal, harbor porpoise and Dall's porpoise, no Level A 
harassment is anticipated due to the confined nature of the facilities, 
ability to position PSOs at stations from which they can observe the 
entire shutdown zones, and the high visibility of the species expected 
to be present at each site. Additionally, much of the anticipated 
activity would involve vibratory driving or installation of small-
diameter, non-steel piles, and include measures designed to minimize 
the possibility of injury. The potential for injury is small for mid- 
and low-frequency cetaceans and sea lions, and is expected to be 
essentially eliminated through implementation of the planned mitigation 
measures--soft start (for impact driving), and shutdown zones.
    DTH and impact driving, as compared with vibratory driving, have 
source characteristics (short, sharp pulses with higher peak levels and 
much sharper rise time to reach those peaks) that are potentially 
injurious or more likely to produce severe behavioral reactions. Given 
sufficient notice through use of soft start, marine mammals are 
expected to move away from a sound source that is annoying prior to its 
becoming potentially injurious or resulting in more severe behavioral 
reactions. Environmental conditions in these waters are expected to 
generally be good, with calm sea states, and we expect conditions would 
allow a high marine mammal detection capability, enabling a high rate 
of success in implementation of shutdowns to avoid injury.
    As described previously, there are multiple species that should be 
considered rare in the proposed project areas and for which we propose 
to authorize only nominal and precautionary take. Therefore, we do not 
expect meaningful impacts to these species (i.e., gray whale, minke 
whale, transient and resident killer whales, and California sea lions) 
and preliminarily find that the total marine mammal take from each of 
the specified activities will have a negligible impact on these marine 
mammal species.
    For remaining species, we discuss the likely effects of the 
specified activities in greater detail. Effects on individuals that are 
taken by Level B harassment, on the basis of reports in the literature 
as well as monitoring from other similar activities, will likely be 
limited to reactions such as increased swimming speeds, increased 
surfacing time, or decreased foraging (if such activity were occurring) 
(e.g., Thorson and Reyff, 2006; U.S. Navy, 2012; Lerma, 2014). Most 
likely, individuals will simply move away from the sound source and be 
temporarily displaced from the areas of pile driving, although even 
this reaction has been observed primarily only in association with 
impact pile driving. The pile driving activities analyzed here are 
similar to, or less impactful than, numerous other construction 
activities conducted in Alaska, San Francisco Bay and in the Puget 
Sound region, which have taken place with no known long-term adverse 
consequences from behavioral harassment.
    The U.S. Navy has conducted multi-year activities potentially 
affecting marine mammals, and typically involving greater levels of 
activity than is contemplated here in various locations such as San 
Diego Bay and Puget Sound. Reporting from these activities has 
similarly reported no apparently consequential behavioral reactions or 
long-term effects on marine mammal populations (Lerma, 2014; U.S. Navy, 
2016a and b).
    Repeated exposures of individuals to relatively low levels of sound 
outside of preferred habitat areas are unlikely to significantly 
disrupt critical behaviors. Thus, even repeated Level B harassment of 
some small subset of the overall stock is unlikely to result in any 
significant realized decrease in viability for the affected 
individuals, and thus would not result in any adverse impact to the 
stock as a whole. Level B harassment will be reduced to the level of 
least practicable adverse impact through use of mitigation measures 
described herein and, if sound produced by project activities is 
sufficiently disturbing, animals are likely to simply avoid the area 
while the activity is occurring. While vibratory driving or DTH 
associated with some project components may produce sound at distances 
of many kilometers from the pile driving site, thus intruding on 
higher-quality habitat, the project sites themselves and the majority 
of sound fields produced by the specified activities are within 
industrialized areas. Therefore, we expect that animals annoyed by 
project sound would simply avoid the area and use more-preferred 
habitats.
    In addition to the expected effects resulting from authorized Level 
B

[[Page 26462]]

harassment, we anticipate that harbor seals, harbor porpoises, and 
Dall's porpoises may sustain some limited Level A harassment in the 
form of auditory injury at four of the facilities, assuming they remain 
within a given distance of the pile driving activity for the full 
number of pile strikes or DTH strikes. Considering the short duration 
to impact drive or vibrate each pile and breaks between pile 
installations (to reset equipment and move pile into place), this means 
an animal would have to remain within the area estimated to be 
ensonified above the Level A harassment threshold for multiple hours. 
This is highly unlikely given marine mammal movement throughout the 
area. Harbor seals and porpoises in these locations that do experience 
PTS would likely only receive slight PTS, i.e., minor degradation of 
hearing capabilities within regions of hearing that align most 
completely with the energy produced by DTH or pile driving, i.e., the 
low-frequency region below 2 kHz, not severe hearing impairment or 
impairment in the regions of greatest hearing sensitivity. If hearing 
impairment occurs, it is most likely that the affected animal would 
lose a few decibels in its hearing sensitivity, which in most cases is 
not likely to meaningfully affect its ability to forage and communicate 
with conspecifics. As described above, we expect that marine mammals 
would be likely to move away from a sound source that represents an 
aversive stimulus, especially at levels that would be expected to 
result in PTS, given sufficient notice through use of soft start. 
Shutdown zones for the porpoises are only slightly smaller than the 
extent of the Level A harassment zones, further minimizing the chances 
for PTS or more severe effects.
    In addition, although affected humpback whales and Steller sea 
lions may be from DPSs that are listed under the ESA, it is unlikely 
that minor noise effects in a small, localized area of sub-optimal 
habitat would have any effect on the stocks' ability to recover. In 
combination, we believe that these factors, as well as the available 
body of evidence from other similar activities, demonstrate that the 
potential effects of the specified activities will have only minor, 
short-term effects on individuals. The specified activities are not 
expected to impact rates of recruitment or survival and will therefore 
not result in population-level impacts.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
     No mortality is anticipated or authorized.
     Use of soft start (for impact driving) is expected to 
minimize Level A harassment.
     No important habitat areas have been identified within the 
project area.
     For all species, the project locations are a very small 
and generally peripheral part of their range.
     Authorized Level A harassment would be very small amounts 
and of low degree.
     Monitoring reports from similar work in many of the 
locations in Alaska have documented little to no effect on individuals 
of the same species impacted by the specified activities.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activities will have a negligible impact 
on the affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under section 101(a)(5)(A) of the MMPA for specified 
activities. The MMPA does not define small numbers and so, in practice, 
where estimated numbers are available, NMFS compares the number of 
individuals taken to the most appropriate estimation of abundance of 
the relevant species or stock in our determination of whether an 
authorization is limited to small numbers of marine mammals. When the 
predicted number of individuals to be taken is fewer than one-third of 
the species or stock abundance, the take is considered to be of small 
numbers. Additionally, other qualitative factors may be considered in 
the analysis, such as the temporal or spatial scale of the activities.
    The amount of take NMFS proposes to authorize is below one-third of 
the estimated stock abundance of all species and stocks (take of 
individuals is less than 14 percent of the abundance of the affected 
stocks for the year of this rulemaking with the maximum amount of 
activity; see Table 19). This is likely a conservative estimate because 
it assumes all takes are of different individual animals, which is 
likely not the case. Some individuals may return multiple times in a 
day, but PSOs would count them as separate takes if they cannot be 
individually identified.
    For fin whale, minke whale, Dall's porpoise, and Southeast Alaska 
harbor porpoise, no valid abundance estimate for the entire stock is 
available. There is no stock-wide abundance estimate for Northeast 
Pacific fin whales. However, Muto et al. (2021) estimate the minimum 
stock size for the areas surveyed is 2,554. Therefore, the 23 maximum 
annual authorized takes of this stock represents small numbers of this 
stock. There is no stock-wide abundance estimate for the Alaska stock 
of minke whales. However, Muto et al. (2021) show over 2,000 animals 
for areas surveyed recently. Therefore, the six maximum annual 
authorized takes of this stock represents small numbers of this stock. 
The Alaska stock of Dall's porpoise has no official NMFS abundance 
estimate for this area, as the most recent estimate is greater than 8 
years old. Nevertheless, the most recent estimate was 83,400 animals 
and it is unlikely this number has drastically declined. Therefore, the 
245 maximum annual authorized takes of this stock represents small 
numbers of this stock. There is no stock-wide abundance estimate for 
the Southeast Alaska stock of harbor porpoises. However, Muto et al. 
(2021) estimate the minimum stock size for the areas surveyed is 1,057. 
Therefore, the 92 maximum annual authorized takes of this stock 
represents small numbers of this stock. Therefore, we preliminarily 
find that small numbers of marine mammals will be taken relative to the 
population size of all stocks.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals will be taken relative to the population 
sizes of the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue regulations and LOAs, NMFS must find that the 
specified activity will not have an ``unmitigable adverse impact'' on 
the subsistence uses of the affected marine mammal species or stocks by 
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50 
CFR 216.103 as an impact resulting from the specified activity: (1) 
that is likely to reduce the availability of the species to a level 
insufficient for a harvest to meet subsistence needs by: (i) causing 
the marine mammals to abandon or avoid hunting areas; (ii) directly 
displacing subsistence users; or (iii) placing physical barriers 
between the marine

[[Page 26463]]

mammals and the subsistence hunters; and (2) that cannot be 
sufficiently mitigated by other measures to increase the availability 
of marine mammals to allow subsistence needs to be met.
    As discussed above in the Effects of Specified Activities on 
Subsistence Uses of Marine Mammals section, subsistence harvest of 
harbor seals and other marine mammals is rare in the project areas and 
local subsistence users have not expressed concern about this project. 
All project activities will take place within industrialized areas 
where subsistence activities do not generally occur. The project also 
will not have an adverse impact on the availability of marine mammals 
for subsistence use at locations farther away, where these construction 
activities are not expected to take place. Some minor, short-term 
harassment of the harbor seals could occur, but any effects on 
subsistence harvest activities in the region will be minimal, and not 
have an adverse impact.
    Based on the effects and location of the specified activity, and 
the mitigation and monitoring measures, NMFS has preliminarily 
determined that there will not be an unmitigable adverse impact on 
subsistence uses from the Coast Guard's planned activities.

Adaptive Management

    The regulations governing the take of marine mammals incidental to 
Coast Guard maintenance construction activities would contain an 
adaptive management component.
    The reporting requirements associated with this proposed rule are 
designed to provide NMFS with monitoring data from the previous year to 
allow consideration of whether any changes are appropriate. The use of 
adaptive management allows NMFS to consider new information from 
different sources to determine (with input from the Coast Guard 
regarding practicability) on an annual basis if mitigation or 
monitoring measures should be modified (including additions or 
deletions). Mitigation measures could be modified if new data suggests 
that such modifications would have a reasonable likelihood of reducing 
adverse effects to marine mammals and if the measures are practicable.
    The following are some of the possible sources of applicable data 
to be considered through the adaptive management process: (1) results 
from monitoring reports, as required by MMPA authorizations; (2) 
results from general marine mammal and sound research; and (3) any 
information which reveals that marine mammals may have been taken in a 
manner, extent, or number not authorized by these regulations or 
subsequent LOAs.

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (16 U.S.C. 
1531 et seq.) requires that each Federal agency insure that any action 
it authorizes, funds, or carries out is not likely to jeopardize the 
continued existence of any endangered or threatened species or result 
in the destruction or adverse modification of designated critical 
habitat. To ensure ESA compliance for the issuance of regulations and 
LOAs, NMFS consults internally, in this case with the Alaska Regional 
Office, whenever we propose to authorize take for endangered or 
threatened species.
    NMFS is proposing to authorize take of Western DPS Steller sea 
lions (Eumetopias jubatus) and Mexico DPS of humpback whales (Megaptera 
novaeangliae), which are listed under the ESA. NMFS' Office of 
Protected Resources has requested initiation of Section 7 consultation 
with the NMFS Alaska Regional Office for the issuance of these 
regulations and LOA. NMFS will conclude the ESA consultation prior to 
reaching a determination regarding the proposed issuance of the 
authorization.

Request for Information

    NMFS requests interested persons to submit comments, information, 
and suggestions concerning the Coast Guard's request and the proposed 
regulations (see ADDRESSES). All comments will be reviewed and 
evaluated as we prepare a final rule and make final determinations on 
whether to issue the requested authorization. This document and 
referenced documents provide all environmental information relating to 
our proposed action for public review.

Classification

    Pursuant to the procedures established to implement Executive Order 
12866, the Office of Management and Budget has determined that this 
proposed rule is not significant.
    Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA), 
the Chief Counsel for Regulation of the Department of Commerce has 
certified to the Chief Counsel for Advocacy of the Small Business 
Administration that this proposed rule, if adopted, would not have a 
significant economic impact on a substantial number of small entities. 
The Coast Guard is the sole entity that would be subject to the 
requirements in these proposed regulations, and the Coast Guard is not 
a small governmental jurisdiction, small organization, or small 
business, as defined by the RFA. Because of this certification, a 
regulatory flexibility analysis is not required and none has been 
prepared.
    This proposed rule does not contain a collection-of-information 
requirement subject to the provisions of the Paperwork Reduction Act 
because the applicant is a federal agency.

List of Subjects in 50 CFR Part 217

    Exports, Fish, Imports, Indians, Labeling, Marine mammals, 
Penalties, Reporting and recordkeeping requirements, Seafood, 
Transportation.

    Dated: April 20, 2023.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, NMFS proposes to amend 50 
CFR part 217 as follows:

PART 217--REGULATIONS GOVERNING THE TAKING OF MARINE MAMMALS 
INCIDENTAL TO SPECIFIED ACTIVITES

0
1. The authority citation for part 217 continues to read as follows:

    Authority: 16 U.S.C. 1361 et seq.

0
2. Add subpart T, consisting of Sec. Sec.  217.190 through 217.199, to 
read as follows:

Subpart T--Taking Marine Mammals Incidental to U.S. Coast Guard 
Alaska Facility Maintenance and Repair Activities

Sec.
217.190 Specified activity and specified geographical region.
217.191 Effective dates.
217.192 Permissible methods of taking.
217.193 Prohibitions.
217.194 Mitigation requirements.
217.195 Requirements for monitoring and reporting.
217.196 Letters of Authorization.
217.197 Renewals and modifications of Letters of Authorization.
217.198-217.199 [Reserved]


Sec.  217.190  Specified activity and specified geographical region.

    (a) Regulations in this subpart apply only to incidental taking of 
marine mammals by the U.S. Coast Guard (Coast Guard) and those persons 
it authorizes or funds to conduct activities on its behalf in the areas 
outlined in paragraph (b) of this section and that occurs incidental to 
maintenance construction activities.
    (b) The taking of marine mammals by the Coast Guard may be 
authorized in a Letter of Authorization (LOA) only if it occurs within 
Gulf of Alaska waters in

[[Page 26464]]

the vicinity of one of the following eight Coast Guard facilities: 
Kodiak, Sitka, Ketchikan, Valdez, Cordova, Juneau, Petersburg, and 
Seward.


Sec.  217.191  Effective dates.

    Regulations in this subpart are effective from [EFFECTIVE DATE OF A 
FINAL RULE], through [DATE 5 YEARS AFTER THE EFFECTIVE DATE OF A FINAL 
RULE].


Sec.  217.192  Permissible methods of taking.

    Under LOAs issued pursuant to Sec.  216.106 of this chapter and 
Sec.  217.196, the Holder of the LOA (hereinafter ``Coast Guard'') may 
incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  217.190(b) by Level A or Level B harassment 
associated with maintenance construction activities, provided the 
activity is in compliance with all terms, conditions, and requirements 
of the regulations in this subpart and the appropriate LOA.


Sec.  217.193  Prohibitions.

    Except for takings described in Sec.  217.192 and authorized by a 
LOA issued under Sec.  216.106 of this chapter and Sec.  217.196, it 
shall be unlawful for any person to do any of the following in 
connection with the activities described in Sec.  217.190 may:
    (a) Violate, or fail to comply with, the terms, conditions, and 
requirements of this subpart or a LOA issued under Sec.  216.106 of 
this chapter and Sec.  217.196;
    (b) Take any marine mammal not specified in such LOAs;
    (c) Take any marine mammal specified in such LOAs in any manner 
other than as authorized;
    (d) Take a marine mammal specified in such LOAs after NMFS 
determines such taking results in more than a negligible impact on the 
species or stocks of such marine mammal; or
    (e) Take a marine mammal specified in such LOAs after NMFS 
determines such taking results in an unmitigable adverse impact on the 
species or stock of such marine mammal for taking for subsistence uses.


Sec.  217.194  Mitigation requirements.

    When conducting the activities identified in Sec.  217.190(a), the 
mitigation measures contained in this subpart and any LOA issued under 
Sec.  216.106 of this chapter and Sec.  217.196 must be implemented. 
These mitigation measures shall include but are not limited to:
    (a) General conditions. (1) A copy of any issued LOA must be in the 
possession of the Coast Guard, supervisory construction personnel, lead 
protected species observers (PSOs), and any other relevant designees of 
the Coast Guard operating under the authority of this LOA at all times 
that activities subject to this LOA are being conducted.
    (2) The Coast Guard shall conduct training between construction 
supervisors and crews and the marine mammal monitoring team and 
relevant Coast Guard staff prior to the start of all down-the-hole 
(DTH), pile driving, cutting or power washing activity and when new 
personnel join the work, so that responsibilities, communication 
procedures, monitoring protocols, and operational procedures are 
clearly understood.
    (3) The Coast Guard shall avoid direct physical interaction with 
marine mammals during construction activity. If a marine mammal comes 
within 20 m of an activity regulated under this subpart, operations 
must cease and vessels must reduce speed to the minimum level required 
to maintain steerage and safe working conditions.
    (b) Shutdown zones. (1) For all DTH, pile driving, cutting or power 
washing activity, the Coast Guard shall implement a minimum shutdown 
zone of a 20-m radius around the pile or DTH hole. If a marine mammal 
comes within or approaches the shutdown zone, such operations shall 
cease.
    (2) For all DTH and pile driving activity, the Coast Guard shall 
implement shutdown zones with radial distances as identified in any LOA 
issued under Sec.  216.106 of this chapter and Sec.  217.196. If a 
marine mammal comes within or approaches the 20-m shutdown zone, such 
operations shall cease.
    (3) For all DTH and pile driving activity, the Coast Guard shall 
designate monitoring zones with radial distances as identified in any 
LOA issued under Sec.  216.106 of this chapter and Sec.  217.196. 
Anticipated observable zones within the designated monitoring zones 
shall be identified in the Marine Mammal Monitoring Plan, subject to 
approval by NMFS.
    (c) Shutdown protocols. (1) The Coast Guard shall deploy Protected 
Species Observers (PSOs) as indicated in the Marine Mammal Monitoring 
Plan, which shall be subject to approval by NMFS, and as described in 
Sec.  217.195.
    (2) For all DTH and pile driving activities, a minimum of one PSO 
shall be stationed at the active pile driving rig or activity site or 
in reasonable proximity in order to monitor the entire shutdown zone.
    (3) Monitoring must take place from 30 minutes prior to initiation 
of DTH and pile driving activity through 30 minutes post-completion of 
DTH and pile driving activity. Pre-start clearance monitoring must be 
conducted during periods of visibility sufficient for the lead PSO to 
determine the shutdown zones clear of marine mammals. DTH and pile 
driving activity may commence following 30 minutes of observation when 
the determination is made.
    (4) If DTH and pile driving activity is delayed or halted due to 
the presence of a marine mammal, the activity may not commence or 
resume until either the animal has voluntarily exited and been visually 
confirmed beyond the shutdown zone or 15 minutes have passed without 
re-detection of the animal.
    (5) Monitoring shall be conducted by trained PSOs, who shall have 
no other assigned tasks during monitoring periods. Trained PSOs shall 
be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown or delay procedures when 
applicable through communication with the equipment operator. The Coast 
Guard shall adhere to the following additional PSO qualifications:
    (i) Independent observers (i.e., not construction personnel) are 
required.
    (ii) At least one observer must have prior experience working as an 
observer.
    (iii) Other observers may substitute education (degree in 
biological science or related field) or training for experience.
    (iv) Where a team of three or more PSOs are required, one observer 
shall be designated as lead observer or monitoring coordinator. The 
lead observer must have prior experience working as an observer.
    (v) The Coast Guard shall submit PSO CVs for approval by NMFS.
    (d) Soft start protocols. The Coast Guard must use soft start 
techniques for impact pile driving. Soft start for impact drivers 
requires contractors to provide an initial set of three strikes at 
reduced energy, followed by a 30-second waiting period, then two 
subsequent reduced energy three-strike sets. Soft start shall be 
implemented at the start of each day's impact pile driving and at any 
time following cessation of impact pile driving for a period of 30 
minutes or longer.


Sec.  217.195  Requirements for monitoring and reporting.

    (a) Marine mammal monitoring plan. The Coast Guard must submit a 
Marine Mammal Monitoring Plan to NMFS for approval in advance of 
construction. Marine mammal monitoring must be conducted in accordance 
with the

[[Page 26465]]

conditions in this section and the Marine Mammal Monitoring Plan.
    (b) PSO requirements. Monitoring must be conducted by qualified, 
NMFS-approved PSOs, in accordance with the following: PSOs must be 
independent (i.e., not construction personnel) and have no other 
assigned tasks during monitoring periods. At least one PSO must have 
prior experience performing the duties of a PSO during construction 
activity pursuant to a NMFS-issued incidental take authorization. Other 
PSOs may substitute other relevant experience, education (degree in 
biological science or related field), or training. PSOs must be 
approved by NMFS prior to beginning any activity subject to this 
subpart.
    (c) Marine mammal observation recording. PSOs must record all 
observations of marine mammals as described in the Marine Mammal 
Monitoring Plan, regardless of distance from the pile being driven. 
PSOs shall document any behavioral reactions in concert with distance 
from piles being driven or removed.
    (d) PSO deployment. The Coast Guard shall deploy additional PSOs to 
monitor harassment zones according to the minimum requirements defined 
in Marine Mammal Monitoring Plan, subject to approval by NMFS. These 
observers shall collect sighting data and behavioral responses to pile 
driving for marine mammal species observed in the region of activity 
during the period of activity, and shall communicate with the shutdown 
zone observer(s) as appropriate with regard to the presence of marine 
mammals. All observers shall be trained in identification and reporting 
of marine mammal behaviors.
    (e) Reporting. (1)(i) Coast Guard shall submit a draft monitoring 
report to NMFS within 90 work days of the completion of required 
monitoring for each portion of the project as well as a comprehensive 
summary report at the end of the project. Coast Guard shall provide a 
final report within 30 days following resolution of comments on the 
draft report. If no work requiring monitoring is conducted within a 
calendar year, Coast Guard shall provide a statement to that effect in 
lieu of a draft report.
    (ii) These reports shall contain, at minimum, the following:
    (A) Dates and times (begin and end) of all marine mammal 
monitoring;
    (B) Construction activities occurring during each daily observation 
period, including the number and type of piles driven or removed and by 
what method (i.e., impact or vibratory) and the total equipment 
duration for vibratory or DTH for each pile or total number of strikes 
for each pile (impact driving, DTH);
    (C) PSO locations during marine mammal monitoring;
    (D) Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
    (E) Upon observation of a marine mammal, the following information: 
Name of PSO who sighted the animal(s) and PSO location and activity at 
time of sighting; time of sighting; identification of the animal(s) 
(e.g., genus and species, lowest possible taxonomic level, or 
unidentified), PSO confidence in identification, and the composition of 
the group if there is a mix of species; distance and bearing of each 
marine mammal observed relative to the pile being driven for each 
sighting (if pile driving was occurring at time of sighting); estimated 
number of animals (min, max, and best estimate); estimated number of 
animals by cohort (adults, juveniles, neonates, group composition, 
etc.); animal's closest point of approach and estimated time spent 
within the harassment zone; and description of any marine mammal 
behavioral observations (e.g., observed behaviors such as feeding or 
traveling), including an assessment of behavioral responses thought to 
have resulted from the activity (e.g., no response or changes in 
behavioral state such as ceasing feeding, changing direction, flushing, 
or breaching);
    (F) Number of marine mammals detected within the harassment zones, 
by species; and
    (G) Detailed information about any implementation of any mitigation 
triggered (e.g., shutdowns and delays), a description of specific 
actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    (2) Coast Guard shall submit a comprehensive summary report to NMFS 
not later than 90 days following the conclusion of marine mammal 
monitoring efforts described in this subpart.
    (3) All draft and final monitoring reports must be submitted to 
[email protected] and [email protected].
    (f) Reporting of injured or dead marine mammals. (1) In the event 
that personnel involved in the construction activities discover an 
injured or dead marine mammal, the LOA-holder must immediately cease 
the specified activities and report the incident to the Office of 
Protected Resources ([email protected] and 
[email protected]), NMFS and to Alaska Regional Stranding 
Coordinator as soon as feasible. If the death or injury was likely 
caused by the specified activity, the Coast Guard must immediately 
cease the specified activities until NMFS is able to review the 
circumstances of the incident and determine what, if any, additional 
measures are appropriate to ensure compliance with the terms of the 
regulations under this subpart and LOAs. The LOA-holder must not resume 
their activities until notified by NMFS. The report must include the 
following information:
    (i) Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    (ii) Species identification (if known) or description of the 
animal(s) involved;
    (iii) Condition of the animal(s) (including carcass condition if 
the animal is dead);
    (iv) Observed behaviors of the animal(s), if alive;
    (v) If available, photographs or video footage of the animal(s); 
and
    (vi) General circumstances under which the animal was discovered.
    (2) [Reserved]


Sec.  217.196  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to the regulations 
under this subpart, the Coast Guard must apply for and obtain an LOA.
    (b) An LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of the regulations 
under this subpart.
    (c) If an LOA expires prior to the expiration date of the 
regulations under this subpart, the Coast Guard may apply for and 
obtain a renewal of the LOA.
    (d) In the event of projected changes to the activity or to 
mitigation and monitoring measures required by an LOA, the Coast Guard 
must apply for and obtain a modification of the LOA as described in 
Sec.  217.197.
    (e) The LOA shall set forth:
    (1) Permissible methods of incidental taking;
    (2) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species, its habitat, and on the availability of the 
species for subsistence uses; and
    (3) Requirements for monitoring and reporting.
    (f) Issuance of the LOA shall be based on a determination that the 
level of taking will be consistent with the findings made for the total 
taking allowable under the regulations of this subpart.

[[Page 26466]]

    (g) Notice of issuance or denial of an LOA shall be published in 
the Federal Register within 30 days of a determination.


Sec.  217.197  Renewals and modifications of Letters of Authorization.

    (a) An LOA issued under Sec.  216.106 of this chapter and Sec.  
217.196 for the activity identified in Sec.  217.190(a) shall be 
renewed or modified upon request by the applicant, provided that:
    (1) The proposed specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for the regulations under this subpart 
(excluding changes made pursuant to the adaptive management provision 
in paragraph (c)(1) of this section); and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOA under the regulations of this 
subpart were implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation, monitoring, or 
reporting (excluding changes made pursuant to the adaptive management 
provision in paragraph (c)(1) of this section) that do not change the 
findings made for the regulations in this subpart or result in no more 
than a minor change in the total estimated number of takes (or 
distribution by species or years), NMFS may publish a notice of 
proposed LOA in the Federal Register, including the associated analysis 
of the change, and solicit public comment before issuing the LOA.
    (c) An LOA issued under Sec.  216.106 of this chapter and Sec.  
217.196 for the activity identified in Sec.  217.190(a) may be modified 
by NMFS under the following circumstances:
    (1) Adaptive management. NMFS may modify (including augment) the 
existing mitigation, monitoring, or reporting measures (after 
consulting with the Coast Guard regarding the practicability of the 
modifications) if doing so creates a reasonable likelihood of more 
effectively accomplishing the goals of the mitigation and monitoring.
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in an LOA:
    (A) Results from the Coast Guard's monitoring from the previous 
year(s).
    (B) Results from other marine mammal and/or sound research or 
studies.
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent, or number not authorized by the regulations under 
this subpart or subsequent LOAs.
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
will publish a notice of proposed LOA in the Federal Register and 
solicit public comment.
    (2) Emergencies. If NMFS determines that an emergency exists that 
poses a significant risk to the well-being of the species or stocks of 
marine mammals specified in LOAs issued pursuant to Sec.  216.106 of 
this chapter and Sec.  217.196, an LOA may be modified without prior 
notice or opportunity for public comment. Notice would be published in 
the Federal Register within 30 days of the action.


Sec. Sec.  217.198-217.199  [Reserved]

[FR Doc. 2023-08719 Filed 4-27-23; 8:45 am]
BILLING CODE 3510-22-P