Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to the Skagway Ore Terminal Redevelopment Project in Skagway, Alaska, 60652-60664 [2023-19029]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 88, Number 170 (Tuesday, September 5, 2023)]
[Notices]
[Pages 60652-60664]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-19029]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XD165]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the Skagway Ore Terminal 
Redevelopment Project in Skagway, Alaska

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an Incidental Harassment Authorization (IHA) to 
Municipality of Skagway (MOS) to incidentally harass marine mammals 
during construction associated with the Ore Terminal redevelopment 
project in Skagway, Alaska.

DATES: This authorization is effective from October 1, 2023 through 
September 30, 2024.

ADDRESSES: Electronic copies of the application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained online at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-municipality-skagways-skagway-ore-terminal-redevelopment. In case of problems accessing these documents, 
please call the contact listed below.

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

SUPPLEMENTARY INFORMATION:

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 proposed or, if the taking is limited to harassment, a notice of a 
proposed IHA is 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 in shorthand 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.

Summary of Request

    On August 9, 2022, NMFS received a request from MOS for an IHA to 
take marine mammals incidental to Ore Terminal redevelopment in 
Skagway, Alaska. Following NMFS' review of the application and 
subsequent revised versions, MOS submitted a final application that was 
deemed adequate and complete on February 23, 2023. The proposed IHA 
published for public comment on April 18, 2023 (88 FR 23627). MOS's 
request is for take of 7 species (including 11 stocks) by Level B and 
Level A harassment. Neither MOS nor NMFS expect serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of Activity

    MOS plans to redevelop the Skagway Ore Terminal in Skagway, Alaska. 
The project will cover construction from fall 2023 through spring 2024 
to avoid construction during cruise ship season with a maximum of 196 
days of pile installation and removal. While the total number of 
estimated pile driving days is 213, some days will include both impact 
and vibratory pile driving, reducing the maximum number of workdays to 
196 (Table 1). This project involves installation and removal of 36 
temporary steel pile guides, removal of 692 piles, and installation of 
244 permanent steel piles. The IHA would be effective from October 1, 
2023 through September 30, 2024. MOS will conduct a total of 142 days 
of vibratory pile installation and removal and 71 days of impact pile 
driving, which was updated to reflect a more accurate number of days 
from the proposed notice of IHA. Sounds resulting from pile 
installation and removal may result in the incidental take of marine

[[Page 60653]]

mammals by Level A and Level B harassment in the form of auditory 
injury or behavioral harassment.

                              Table 1--Pile Installation Methods and Durations \+\
----------------------------------------------------------------------------------------------------------------
                                       Number of                                   Piles driven/  Estimated days
         Pile size, method               piles        Duration/strikes per pile         day             \1\
----------------------------------------------------------------------------------------------------------------
36-in to 48-in steel pile,**                    74  1800 strikes................               2              34
 Impact Installation.
24-in steel pile, Impact                       170  700 strikes.................               5              37
 Installation.
Up to 30-in steel pile,* Vibratory             511  45 min......................               5             103
 Installation and Removal.
36-in to 48 in steel pile,**                    74  45 min......................               5              15
 Vibratory Installation.
14-in timber pile, Vibratory                   423  21 min......................              18              24
 Removal.
----------------------------------------------------------------------------------------------------------------
* Includes piles sizes: 10.75-in, 14-in, 16-in, 20-in, 24-in, 28-in, and 30-in.
** Includes pile sizes: 36-in, 42-in, and 48-in.
\1\ Estimated days are based on individual days of work, in reality work could occur on the same day reducing
  the total number of workdays to 196.
\+\ Changes were made to this table from proposed to final including: MOS updating their estimated work days and
  including temporary pile installation and removal in the up to 30-in steel piles.

    A further detailed description of the planned construction project 
is provided in the Federal Register notice for the proposed IHA (88 FR 
23627, April 18, 2023). Please refer to that Federal Register notice 
for the description of the specified activity. Mitigation, monitoring, 
and reporting measures are described in detail later in this document 
(please see Mitigation and Monitoring and Reporting).

Comments and Responses

    A notice of NMFS' proposal to issue an IHA to MOS was published in 
the Federal Register on April 18, 2023 (88 FR 23627). That notice 
described, in detail, MOS activities, the marine mammal species that 
may be affected by the activities, and the anticipated effects on 
marine mammals. During the 30-day public comment period only non-
substantive comments were received and are not discussed further.

Changes From the Proposed IHA to Final IHA

    Changes were made between publication of the notice of proposed IHA 
and this notice of final IHA. Changes have been made to correct 
typographical errors in pile numbers in the proposed Federal Register 
notice. The effective dates of the IHA, the maximum number of days of 
pile driving activity, and the Protected Species Observer (PSO) 
monitoring locations have been updated at the request of MOS. Harbor 
porpoise stock abundance was corrected and language limiting monitoring 
to a specific Beaufort sea state was removed. Additionally, take by 
Level B and Level A harassment has been updated for harbor porpoise, 
Dall's porpoise, harbor seal, and Steller sea lion to reflect the 
updated number of workdays and correct mistakes in ensonified area 
calculations.
    Since the Federal Register notice of the proposed IHA was published 
(88 FR 23627, April 18, 2023), NMFS published the final 2022 Alaska and 
Pacific Stock Assessment Reports (SARs), which describe revised stock 
structures under the MMPA for humpback whales and southeast Alaska 
harbor porpoise (Carretta et al., 2023; Young et al., 2023). In the 
notice of proposed IHA, we explained that although we typically 
consider updated peer-reviewed data provided in draft SARs to be the 
best available science, and use the information accordingly, we make 
exception for proposed revised stock structures. Upon finalization of 
these revised stock structures, we have made appropriate updates, 
including description of the potentially affected stocks (see Table 2), 
attribution of take numbers to stock (see Estimated Take), and by 
updating our analyses to ensure the necessary determinations are made 
for the new stocks (see Negligible Impact Analysis and Determination 
and Small Numbers).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history of the potentially affected species. NMFS 
fully considered all of this information, and we refer the reader to 
these descriptions, instead of reprinting the information. Additional 
information regarding population trends and threats may be found in 
NMFS' Stock Assessment Reports (SARs; https://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 (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species or stocks for which take is expected and 
authorized to be authorized for this activity, and summarizes 
information related to the population or stock, including regulatory 
status under the MMPA and Endangered Species Act (ESA) and potential 
biological removal (PBR), where known. PBR is 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 (as described in 
NMFS' SARs). While no serious injury or 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 or stocks 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 this region are assessed in 
NMFS' 2021 Alaska Marine Mammal SARs. All values presented in Table 2 
are the most recent available at the time of publication (including 
from the draft 2022 SARs) and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

[[Page 60654]]



                                              Table 2--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 Balaenopteridae (rorquals):
    Humpback whale..................  Megaptera novaeanglinae  Hawai[revaps]i.........  -,-,N               11,278 (0.56, 7,265,          127      27.09
                                                                                                             2020).
                                                               Mexico-North Pacific...  T,D,Y               918 (0.217, UNK, 2006)        UNK       0.57
    Minke whale.....................  Balaenoptera             Alaska.................  -,-,N               UNK...................         NA          0
                                       acutorostra.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Killer whale....................  Orca orcinus...........  Eastern North Pacific,   -,-,N               302 (N/A, 302, 2018)..        2.2        0.2
                                                                Norther Residents,
                                                                Southeast Alaska.
                                                               Eastern North Pacific    -,-,N               1,920 (N/A, 1,920,             19        1.3
                                                                Alaska Residents.                            2019).
                                                               West Coast Transients..  -,-,N               349 (N/A, 349, 2018)..        3.5        0.4
                                                               Gulf, Aleutian, Bering   -,-,N               587 (N/A, 587, 2020)..        5.9        0.8
                                                                Transients.
Family Phocoenidae (porpoises):
    Harbor Porpoise.................  Phocoena phocoena......  Northern Southeast       -,-,N               1,619 (0.26, 1,250,            13        5.6
                                                                Alaska Inland Waters.                        2019).
    Dall's porpoise\4\..............  Phocoenoides dalli.....  Alaska.................  -,-,N               15,432 (0.28, 13, 110,        131         37
                                                                                                             2021).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
Steller sea lion....................  Eumetopias jubatus.....  Western Stock..........  E,D,Y               52,932 (N/A, 52,932,          318        254
                                                                                                             2019).
                                                               Eastern Stock..........  -,-,N               43,201 (N/A, 43,201,        2,592        112
                                                                                                             2017).
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vituline           Alaska-Lynn Canal/       -,-,N               13,388 (N/A, 11,867,          214         50
                                       richardii.               Stephens Passage.                            2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (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-assessment-reports. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury 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\ 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.

    As indicated above, all 7 species (with 11 managed stocks) in Table 
2 temporally and spatially co-occur with the activity to the degree 
that take is reasonably likely to occur, and for which we have 
authorized.
    A detailed description of the species likely to be affected by 
MOS's construction project, including brief introductions to the 
species and relevant stocks as well as available information regarding 
population trends and threats, and information regarding local 
occurrence, were provided in the Federal Register notice for the 
proposed IHA (88 FR 23627, April 18, 2023); since that time, we are not 
aware of any changes in the status of these species and stocks; 
therefore, detailed descriptions are not provided here. However, there 
was a mistake in the harbor porpoise stock abundance listed in the 
notice for the proposed IHA, and the value was updated in this notice 
of final IHA. Please refer to that Federal Register notice for these 
descriptions. Please also refer to the NMFS website (https://www.fisheries.noaa.gov/find-species) for generalized species accounts.

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. 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, 2019) recommended that marine mammals be divided into hearing 
groups based on directly measured (behavioral or auditory evoked 
potential techniques) or estimated hearing ranges (behavioral response 
data, anatomical modeling, etc.). Note that no direct measurements of 
hearing ability have been successfully completed for mysticetes (i.e., 
low-frequency cetaceans). Subsequently, NMFS (2018) 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 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their

[[Page 60655]]

associated hearing ranges are provided in Table 3.

                  Table 3--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).
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.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from the MOS's pile driving 
activities have the potential to result in behavioral harassment of 
marine mammals in the vicinity of the project area. The notice of the 
proposed IHA (88 FR 23627, April 18, 2023) included a discussion of the 
effects of anthropogenic noise on marine mammals and the potential 
effects of underwater noise from the MOS's pile driving activities on 
marine mammals and their habitat. That information and analysis is 
incorporated by reference into this final IHA determination and is not 
repeated here; please refer to the notice of the proposed IHA (88 FR 
23627, April 18, 2023).

Estimated Take of Marine Mammals

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform both NMFS' consideration 
of ``small numbers,'' and the negligible impact determinations.
    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 primarily be by Level B harassment, as use 
of the acoustic sources (i.e., vibratory and impact pile driving) has 
the potential to result in disruption of behavioral patterns for 
individual marine mammals. There is also some potential for auditory 
injury (Level A harassment) to result. The mitigation and monitoring 
measures are expected to minimize the severity of the taking to the 
extent practicable. As described previously, no serious injury or 
mortality is anticipated or authorized for this activity. Below, we 
describe how the take numbers are estimated.
    For acoustic impacts, 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) the number of days of activities. We note 
that while these factors can contribute to a basic calculation to 
provide an initial prediction of potential 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 take estimates.

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 permanent threshold shift (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 or exposure context (e.g., frequency, predictability, duty 
cycle, duration of the exposure, signal-to-noise ratio, distance to the 
source), the environment (e.g., bathymetry, other noises in the area, 
predators in the area), and the receiving animals (hearing, motivation, 
experience, demography, life stage, depth) and can be difficult to 
predict (e.g., Southall et al., 2007, 2021, Ellison et al., 2012). 
Based on what the available science indicates and the practical need to 
use a threshold based on a metric that is both predictable and 
measurable for most activities, NMFS typically uses a generalized 
acoustic threshold based on received level to estimate the onset of 
behavioral harassment. NMFS generally predicts that marine mammals are 
likely to be behaviorally harassed in a manner considered to be Level B 
harassment when exposed to underwater anthropogenic noise above root-
mean-squared pressure received levels (RMS SPL) of 120 dB (referenced 
to 1 micropascal (re 1 [mu]Pa)) for continuous (e.g., vibratory pile 
driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa for non-
explosive impulsive (e.g., seismic airguns) or intermittent (e.g., 
scientific sonar) sources. Generally speaking, Level B harassment take 
estimates based on these behavioral harassment thresholds are expected 
to include any likely takes by temporary threshold shift (TTS) as, in 
most cases, the likelihood

[[Page 60656]]

of TTS occurs at distances from the source less than those at which 
behavioral harassment is likely. TTS of a sufficient degree can 
manifest as behavioral harassment, as reduced hearing sensitivity and 
the potential reduced opportunities to detect important signals 
(conspecific communication, predators, prey) may result in changes in 
behavior patterns that would not otherwise occur.
    MOS's activity includes the use of continuous (vibratory pile 
driving) and impulsive (impact pile driving) sources, and therefore the 
RMS SPL thresholds of 120 and 160 dB re 1 [mu]Pa are applicable.
    Level A Harassment--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). MOS's 
activity includes the use of impulsive (impact pile driving) and non-
impulsive (vibratory pile driving) 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 4--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 this 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 are used in estimating the area ensonified above the 
acoustic thresholds, including source levels and transmission loss 
coefficient.
    The sound field in the project area is the existing background 
noise plus additional construction noise from the planned project. 
Marine mammals are expected to be affected via sound generated by the 
primary components of the project (i.e., impact pile driving and 
vibratory pile driving and removal).
    In order to calculate distances to the Level A harassment and Level 
B harassment thresholds for the methods and piles being used in this 
project, NMFS used acoustic monitoring data from other locations to 
develop source levels for the various pile types, sizes and methods 
(Table 5).

                        Table 5--Observed Source Levels for Pile Installation and Removal
----------------------------------------------------------------------------------------------------------------
                                          Peak SPLs     RMS SPLs
           Pile size, method                 (dB)         (dB)      SELss (dB)               Source
----------------------------------------------------------------------------------------------------------------
36-in to 48-in steel pile,** Impact              210          193          183  Caltrans 2020.
 Installation.
24-in steel pile, Impact Installation..          203          189          177  Caltrans 2020.
Up to 30-in steel pile,* Vibratory               196          159           NA  Caltrans 2020.
 Installation and Removal.
36-in to 48-in steel pile,** Vibratory           180          170           NA  Caltrans 2015.
 Installation.
14-in timber pile, Vibratory Removal...           NA          158           NA  Greenbusch 2018.
----------------------------------------------------------------------------------------------------------------
Note: SPLs = single strike sound pressure level; RMS = root mean square.
* Includes piles sizes: 10.75-in, 14-in, 16-in, 20-in, 24-in, 28-in, and 30-in.
** Includes pile sizes: 36-in, 42-in, and 48-in.

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:
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

[[Page 60657]]

spherical and cylindrical spreading loss conditions, which is the most 
appropriate assumption for MOS's planned activities. The Level B 
harassment zones for the planned activities are shown in Table 6.

Level A Harassment Zones

    The ensonified area associated with Level A harassment is more 
technically challenging to predict due to the need to account for a 
duration component. Therefore, NMFS developed an optional User 
Spreadsheet tool to accompany the Technical Guidance that can be used 
to relatively simply predict an isopleth distance for use in 
conjunction with marine mammal density or occurrence to help predict 
potential takes. We note that because of some of the assumptions 
included in the methods underlying this optional tool, we anticipate 
that the resulting isopleth estimates are typically going to be 
overestimates of some degree, which may result in an overestimate of 
potential take by Level A harassment. However, this optional tool 
offers the best way to estimate isopleth distances when more 
sophisticated modeling methods are not available or practical. For 
stationary sources, such as pile installation or removal, the optional 
User Spreadsheet tool predicts the distance at which, if a marine 
mammal remained at that distance for the duration of the activity, it 
would be expected to incur PTS. The isopleths generated by the User 
Spreadsheet used the same TL coefficient as the Level B harassment zone 
calculations (i.e., the practical spreading value of 15). Inputs used 
in the User Spreadsheet (e.g., number of piles per day, duration and/or 
strikes per pile, source levels) are presented in Table 1 and Table 5. 
The resulting isopleths are reported in Table 6.

                            Table 6--Level A and Level B Harassment Isopleths and Areas for Impact and Vibratory Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Level A harassment zone (m)/area ensonified (km\2\) \1\                 Level B
                                                        -------------------------------------------------------------------------------- harassment zone
                        Activity                                                                                                             (m)/area
                                                           LF cetacean     MF cetacean     HF cetacean       Phocids        Otariids        ensonified
                                                                                                                                             (km\2\)
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-in to 48-in steel pile,** Impact Installation.......    2,345.7/5.85       83.4/0.02    2,794.1/6.95    1,255.3/2.20       91.4/0.05     1,584.9/3.23
24-in steel pile, Impact Installation..................    1,245.8/2.16       44.3/0.01    1,483.9/2.88      666.7/0.88       48.5/0.01       857.7/1.23
Up to 30-in steel pile,* Vibratory Installation and          12.1/<0.01       1.1/<0.01      17.9/<0.01       7.4/<0.01       0.5/<0.01       3,981/9.08
 Removal...............................................
36-in to 48-in steel pile,** Vibratory Installation....       65.6/0.01       5.8/<0.01         97/0.03       39.9/0.01       2.8/<0.01     21,544/20.36
14-in timber pile, Vibratory Removal...................      14.7/<0.01       1.3/<0.01      21.7/<0.01       8.9/<0.01       0.6/<0.01     3,414.5/8.06
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Includes piles sizes: 10.75-in, 14-in, 16-in, 20-in, 24-in, 28-in, and 30-in.
** Includes pile sizes: 36-in, 42-in, and 48-in.
\1\ Ensonified areas were updated from proposed to final to correct a mistake.

Marine Mammal Occurrence

    In this section we provide information about the occurrence of 
marine mammals, including density or other relevant information which 
will inform the take calculations.
    For marine mammal density information in the Skagway area we use 
data from the Pacific Navy Marine Species Density Database (U.S. Navy, 
2021) and sources specific to the Skagway area to estimate take for 
marine mammals. The Marine Species Density Database incorporates 
analyzed literature and research for marine mammal density estimates 
per season for the Gulf of Alaska and the Western Behm Canal. The 
Western Behm Canal is closer to the Project site and geographically 
more similar (an inlet compared to open ocean); therefore, density 
estimates for Western Behm Canal are used as proxies. Density estimates 
specific to Taiya Inlet or Lynn Canal are not available for any of the 
species addressed in this application, and therefore takes must be 
estimated based on the nearest available and most appropriate density 
estimates, plus site-specific knowledge and professional judgement. 
Table 7 density estimates are calculated based on winter density 
estimates of Western Behm Canal.

      Table 7--Density of Marine Mammal Species in the Project Area
------------------------------------------------------------------------
                                                                Density
                           Species                               (per
                                                                km\2\)
------------------------------------------------------------------------
Humpback Whale..............................................      0.0081
Minke Whale.................................................      0.0017
Dall's Porpoise.............................................      0.1210
Harbor Porpoise.............................................      0.0473
Killer Whale................................................      0.0041
Harbor Seal.................................................       1.730
Steller Sea Lion............................................      0.0123
------------------------------------------------------------------------

Take Estimation

    Here we describe how the information provided above is synthesized 
to produce a quantitative estimate of the take that is reasonably 
likely to occur and authorized.
    Using the overall area of disturbance generated by pile removal and 
installation given calculated distances to attenuation below 
disturbance (Level B harassment) thresholds, incidental take for each 
activity is estimated by the following equation:

Incidental take estimate = species density * ensonified area * days of 
pile-related activity

    Due to few observational data available for marine mammals in Taiya 
Inlet and Lynn Canal in the winter, this equation is a reasonable 
extrapolation for take estimates, which relies on the likelihood that a 
species is present within the ensonified area on a day where the 
activity is occurring. Some species were increased or reduced from the 
calculated take when it did not align with local sighting data. Steller 
sea lion take estimates are increased to one potential take per day and 
killer whale take estimates are increased based on sightings of groups 
of killer whales four to five times per year. Harbor seal take was 
reduced as the estimate was high for winter when the work will occur. 
The estimation of take by Level A harassment is based on the likelihood 
that marine mammals would enter the Level A harassment zone without 
detection.

                            Table 8--Authorized Amount of Taking and Percent of Stock
----------------------------------------------------------------------------------------------------------------
                                                                Take by      Take by
               Species                         Stock            Level A      Level B     Total take   Percent of
                                                               harassment   harassment                  stock
----------------------------------------------------------------------------------------------------------------
Humpback Whale......................  Hawaii \3\............            2           13           15           <1
                                      Mexico-North Pacific              0            1            1           <1
                                       \3\.

[[Page 60658]]

 
Minke Whale.........................  Alaska................            2            6            8       \1\ NA
Dall's Porpoise.....................  Alaska................           43          193      \2\ 236          1.8
Harbor Porpoise.....................  Southeast Alaska......           17           75       \2\ 92          5.7
Killer Whale........................  Eastern North Pacific,            2           90           92         2.91
                                       Northern Residents,
                                       Southeast Alaska +
                                       Eastern North
                                       Pacific, Alaska
                                       Residents + West
                                       Coast Transients +
                                       Gulf, Aleutian,
                                       Bering Transients.
Harbor Seal.........................  Alaska--Lynn Canal/             193        2,760    \2\ 2,953         22.1
                                       Stephens Passage.
Steller Sea Lion....................  Eastern US + Western              2          196      \2\ 198           <1
                                       US.
----------------------------------------------------------------------------------------------------------------
\1\ Alaska SAR does not have an estimated population size for the Alaska stock of minke whales due only a
  portion of the stock's range being surveyed and such few whales seen during stock abundance surveys.
\2\ Take was updated to reflect updated workdays and corrected ensonified areas.
\3\ Take was updated and allocated for the revised stock structure in the 2022 SARs.

Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses. 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, NMFS 
considers 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.
    NMFS requires the following mitigation measures be implemented for 
MOS's pile installation and removal activities.

Mitigation Measures

    MOS must follow mitigation measures as specified below:
     Ensure that construction supervisors and crews, the 
monitoring team, and relevant MOS staff are trained prior to the start 
of all pile driving activity, so that responsibilities, communication 
procedures, monitoring protocols, and operational procedures are 
clearly understood. New personnel joining during the project must be 
trained prior to commencing work;
     Employ PSOs and establish monitoring locations as 
described in the application and the IHA. MOS 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 pile driving and removal, 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 pile driving and 
removal activities will ensure that the entire shutdown zone is visible 
during pile driving activities. Should environmental conditions 
deteriorate such that marine mammals within the entire shutdown zone 
will not be visible (e.g., fog, heavy rain), pile driving and removal 
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 pile driving activity (i.e., pre-clearance monitoring) 
through 30 minutes post-completion of pile driving activity;
     Pre-start clearance monitoring must be conducted during 
periods of visibility sufficient for the lead PSO to determine that the 
shutdown zones indicated in Table 9 are clear of marine mammals. Pile 
driving may commence following 30 minutes of observation when the 
determination is made that the shutdown zones are clear of marine 
mammals;
     MOS must use soft start techniques when 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;
     If a marine mammal is observed entering or within the 
shutdown zones indicated in Table 9, pile driving must be delayed or 
halted. If 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 (Table 9) or 15 minutes have passed without re-detection 
of the animal; and
     As planned by MOS, in water activities will take place 
only between civil dawn and civil dusk and for a limited duration after 
dusk with lighting when PSOs can effectively monitor for the presence 
of marine mammals; when the entire shutdown zone and adjacent waters 
are visible (e.g., monitoring effectiveness in not reduced due to rain, 
fog, snow, etc.).

Shutdown Zones

    MOS will establish shutdown zones for all pile driving activities. 
The purpose of a shutdown zone is generally

[[Page 60659]]

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 would be based upon the 
Level A harassment zone for each pile size/type and driving method 
where applicable, as shown in Table 9.
    For in-water heavy machinery activities other than pile driving, if 
a marine mammal comes within 10 meters (m), work generating underwater 
noise will stop and vessels will reduce speed to the minimum level 
required to maintain steerage and safe working conditions. A 10 m 
shutdown zone would also serve to protect marine mammals from physical 
interactions with project vessels during pile driving and other 
construction activities, such as barge positioning or drilling. If an 
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 
indicated in Table 9 or 15 minutes have passed without re-detection of 
the animal. Construction activities must be halted upon observation of 
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.
    All marine mammals will be monitored in the Level B harassment 
zones and throughout the area as far as visual monitoring can take 
place. If a marine mammal enters the Level B harassment zone, in-water 
activities will continue and the animal's presence within the estimated 
harassment zone will be documented.
    MOS will also establish shutdown zones for all marine mammals for 
which take has not been authorized or for which incidental take has 
been authorized but the authorized number of takes has been met. These 
zones are equivalent to the Level B harassment zones for each activity. 
If a marine mammal species not covered under this IHA enters the 
shutdown zone, all in-water activities will cease until the animal 
leaves the zone or has not been observed for at least 15 minutes, and 
NMFS will be notified about species and precautions taken. Pile driving 
will proceed if the non-IHA species is observed to leave the Level B 
harassment zone or if 15 minutes have passed since the last 
observation.
    If shutdown and/or clearance procedures would result in an imminent 
safety concern, as determined by MOS or its designated officials, the 
in-water activity will be allowed to continue until the safety concern 
has been addressed, and the animal will be continuously monitored.
    The large HF shutdown zones will be effectively monitored from the 
Kasidaya land based monitoring station and vessel traversing the south 
end of the largest Level B harassment zone. See the figures in MOS 
application for further details.

                                  Table 9--Shutdown Zones and Monitoring Zones
----------------------------------------------------------------------------------------------------------------
                                                      Minimum shutdown zone
                             -----------------------------------------------------------------------  Harassment
          Activity             Low-frequency    Mid-frequency    High-frequency                          zone
                               (LF) cetaceans   (MF) cetaceans   (HF) cetaceans   Phocid    Otariid
----------------------------------------------------------------------------------------------------------------
36-in to 48-in steel pile,**            2,350               85            2,795     1,260        95        1,585
 Impact Installation........
24-in steel pile, Impact                1,250               45            1,485       670        50          860
 Installation...............
Up to 30-in steel pile,*                   15               10               20        10        10        3,985
 Vibratory Installation and
 Removal....................
36-in to 48-in steel pile,**               70               10              100        40        10   \1\ 16,300
 Vibratory Installation.....
14-in timber pile, Vibratory               15               10               25        10        10        3,415
 Removal....................
----------------------------------------------------------------------------------------------------------------
* Includes piles sizes: 10.75-in, 14-in, 16-in, 20-in, 24-in, 28-in, and 30-in.
** Includes pile sizes: 36-in, 42-in, and 48-in.
\1\ Shoreline of Taiya Inlet obstructs sound transmission and limits the extent of the Level B harassment zone.

Protected Species Observers

    The placement of PSOs during all construction activities (described 
in the Monitoring and Reporting section) will ensure that the entire 
shutdown zone is visible. Should environmental conditions deteriorate 
such that the entire shutdown zone would not be visible (e.g., fog, 
heavy rain), pile driving would be delayed until the PSO is confident 
marine mammals within the shutdown zone could be detected.
    PSOs will monitor the full shutdown zones and the remaining Level A 
harassment and the Level B harassment zones to the extent practicable. 
Monitoring zones provide utility for observing by establishing 
monitoring protocols for areas adjacent to the shutdown zones. 
Monitoring zones enable observers to be aware of and communicate the 
presence of marine mammals in the project areas outside the shutdown 
zones and thus prepare for a potential cessation of activity should the 
animal enter the shutdown zone.

Pre-Activity Monitoring

    Prior to the start of daily in-water construction activity, or 
whenever a break in pile driving of 30 minutes or longer occurs, PSOs 
will observe the shutdown and monitoring zones for a period of 30 
minutes. The shutdown zone will be considered cleared when a marine 
mammal has not been observed within the zone for that 30-minute period. 
If a marine mammal is observed within the shutdown zones listed in 
Table 9, pile driving activity will be delayed or halted. If work 
ceases for more than 30 minutes, the pre-activity monitoring of the 
shutdown zones will commence. A determination that the shutdown zone is 
clear must be made during a period of good visibility (i.e., the entire 
shutdown zone and surrounding waters must be visible to the naked eye).

Soft Start Procedures

    Soft start procedures provide additional protection to marine 
mammals by providing warning and/or giving marine mammals a chance to 
leave the area prior to the hammer operating at full capacity. For 
impact pile driving, contractors will be required to provide an initial 
set of three strikes from the hammer at reduced energy, followed by a 
30-second waiting period, then two subsequent reduced-energy strike 
sets. Soft start will 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.
    Based on our evaluation of MOS's planned measures, as well as other 
measures considered by NMFS, NMFS has determined that the mitigation 
measures provide the means effecting the least practicable impact on 
the affected species or stocks and their habitat, paying particular 
attention to

[[Page 60660]]

rookeries, mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such 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 while 
conducting the activities. 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 activity; 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 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 other important physical components of 
marine mammal habitat); and,
     Mitigation and monitoring effectiveness.

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
conditions in this section and the IHA. Marine mammal monitoring during 
pile driving activities will be conducted by PSOs meeting the following 
requirements:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods;
     At least one PSO will have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
     Other PSOs may substitute education (degree in biological 
science or related field) or training for experience; and
     Where a team of three or more PSOs is required, a lead 
observer or monitoring coordinator will be designated. The lead 
observer will be required to have prior experience working as a marine 
mammal observer during construction.
    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.
     MOS must employ up to five PSOs during all pile driving 
activities depending on the size of the monitoring and shutdown zones. 
A minimum of two PSOs (including the lead 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.
     MOS must establish the following monitoring locations with 
the best views of monitoring zones as described in the IHA and 
Application.
     Up to five monitors will be used at a time depending on 
the size of the monitoring area. PSOs would be deployed in strategic 
locations around the area of potential effects at all times during in-
water pile driving and removal. PSOs will be positioned at locations 
that provide full views of the vibratory and impact hammering 
monitoring zones and the shutdown zones. The land based monitoring 
locations will be at the Railroad Dock, Yakutania Point, and Kasidaya. 
The larger monitoring zones will be monitored using PSOs in a mobile 
vessel traversing the south end of the monitoring zone in addition to 
the land based locations. All PSOs will have access to high-quality 
binoculars, range finders to monitor distances, and a compass to record 
bearing to animals as well as radios or cells phones for maintaining 
contact with work crews.
    Monitoring will be conducted 30 minutes before, during, and 30 
minutes after all in water construction activities. In addition, PSOs 
will record all incidents of marine mammal occurrence, regardless of 
distance from activity, and will document any behavioral reactions in 
concert with distance from piles being driven or removed. Pile driving 
activities include the time to install or remove a single pile or 
series of piles, as long as the time elapsed between uses of the pile 
driving equipment is no more than 30 minutes.
    MOS shall conduct briefings between construction supervisors and 
crews, PSOs, MOS staff prior to the start of all pile driving 
activities and when new personnel join the work. These briefings will 
explain responsibilities, communication procedures, marine mammal 
monitoring protocol, and operational procedures.

Acoustic Monitoring

    Acoustic monitoring will be conducted during in-water pile 
installation and removal, for each of the three scenarios (impact 
installation of steel piles, vibratory installation and removal of 
steel piles, and vibratory removal of timber piles). Collection of the 
acoustic data will be accomplished using a minimum of two hydrophones. 
At least one land-based microphone will also be deployed to record 
airborne sound levels. For underwater acoustic monitoring, the 
hydrophones will be placed such that there is a direct line of acoustic 
transmission through the water column between the impact or vibratory 
hammer and the hydrophones, without any interposing structures 
(including other piles) that could impede sound transfer, when 
possible. All acoustical recordings will be conducted at least 1 meter 
below the water surface and 1 meter above the sea floor, or as 
applicable to optimize sound recordings in the nearshore environment. 
Background noise recordings (in the

[[Page 60661]]

absence of pile-related work) will also be made during the study to 
provide a baseline background noise profile.
    All sensors, signal conditioning equipment, and sampling equipment 
will be calibrated at the start of the monitoring period to National 
Institute of Standards and Technology standards and will be rechecked 
at the start of each day.
    A stationary two-channel hydrophone recording system will be 
deployed to record continuous sound associated with pile driving and 
removal activities during the monitoring period. Key methodological 
details are as follows:
     Prior to monitoring, water depth measurements will be made 
to ensure that hydrophones will not drag on the bottom during tidal 
changes. The hydrophones will be placed at least 1 meter below the 
surface and 1 meter above the seafloor. The depth with respect to the 
bottom may vary somewhat due to tidal changes and current effects.
     One hydrophone will be deployed to maintain a constant 
distance of approximately 10 meters from the pile-related noise source, 
and the other would be at a further distance from the pile-related 
noise source.
     The hydrophones, signal conditioning, and recording 
equipment will be configured to acquire maximum source levels without 
clipping recorded data. Post-analysis of underwater sound level signals 
would include the following:
     Impact Pile Driving:
    1. Determination of the maximum absolute value of the instantaneous 
pressure within each strike.
    2. RMS value for the period of which 90 percent of the energy is 
represented (RMS90 (here forward referred to as 
SPLRMS), 5 percent to 95 percent) for each absolute peak 
pile strike.
    3. Mean and standard deviation/error of the SPLRMS 
percent for all pile strikes of each pile.
    4. Rise time.
    5. Number of strikes per pile and per day.
    6. Sound exposure level (SEL) of the single pile strike with the 
absolute peak (PK), mean SEL.
    7. Minimum, maximum, mean, and median cumulative SEL (cumulative 
SEL = single strike SEL + 10*LOG10(number of pile strikes)).
    8. Frequency spectrum, between 20 hertz (Hz) and 20 kilohertz 
(kHz), for up to eight successive strikes with similar sound level.
     Vibratory Pile Driving and Removal:
    1. RMS values (median, standard deviation/error, minimum, and 
maximum) for each recorded pile. The 10-second, RMS-averaged values 
will be used for determining the source value and extent of the 120 dB 
underwater isopleth.
    2. Frequency spectra will be provided for each functional hearing 
group as outlined in NOAA's 2018 guidance (NOAA, 2018).
     All underwater source levels will be recorded as measured 
and could additionally be standardized to a reference distance of 10 
meters (33 feet).
     Post-analysis of airborne noise will be presented in an 
unweighted format, and will include the following:
    1. The unweighted RMS values (average, minimum, and maximum) for 
each recorded pile. The average values will be used for determining the 
extent of the airborne isopleths relative to species specific criteria.
    2. Frequency spectra will be provided from 10 Hz to 20 kHz for 
representative pile-related activity.
    3. All airborne source levels will be standardized to a reference 
distance of approximately 15 meters (50 feet).
     Acoustic monitoring will be performed using a standardized 
method that will facilitate comparisons with other studies. In the 
event that pile-related noise trends toward consistently surpassing 
calculated levels, NMFS will be contacted immediately to revise 
Shutdown Zones as needed.

Reporting

    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities, or 60 days prior to a requested date of issuance from any 
future IHAs 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 vibratory) and the total 
equipment duration for vibratory removal for each pile or total number 
of strikes for each pile (impact driving);
     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 the time of sighting;
     Time of sighting;
     Identification of the animal(s) (e.g., genus/species, 
lowest possible taxonomic level, or unidentifiable), 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 sightings (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, sex class, etc.);
     Animal's closest point of approach and estimated time 
spent within the harassment zone;
     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 and shutdown zones; by species;
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensured, and resulting changes in behavior of the 
animal(s), if any; and
     If visibility degrades to where PSO(s) cannot view the 
entire harassment zones, additional PSOs may be positioned so that the 
entire width is visible, or work will be halted until the entire width 
is visible to ensure that any humpback whales entering or within the 
harassment zone are detected by PSOs.
    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.

Acoustic Monitoring Report

    The Acoustic Monitoring Report must include:
     Type and size of pile being driven, substrate type, method 
of driving during recordings (e.g., hammer model, energy), and total 
pile driving duration;
     Whether a sound attenuation device is used and, if so, a 
detailed description

[[Page 60662]]

of the device and the duration of its use per pile;
     A description of the sound monitoring equipment, including 
a detailed description of the depths and locations of the hydrophones 
relative to the pile being driven;
     For impact pile driving: Number of strikes and strike 
rate, depth of substrate to penetrate; pulse duration and mean, median, 
and maximum sound levels (dB re: 1 [micro]Pa); root mean square sound 
pressure level (SPLRMS), cumulative sound exposure level 
(SELcum), peak sound pressure level (SPLpeak), 
and single strike exposure sound level (SEL s-s);
     For vibratory driving/removal (per pile): Duration of 
driving per pile; mean, median, and maximum sound levels (dB re: 1 
[mu]Pa): Root mean square sound pressure level (SPLRMS), 
cumulative sound exposure level (SELcum) (and timeframe over 
which the sound is averaged);
     One-third octave band spectrum and power spectral density 
plot for each pile monitored and average spectrum for each type of 
driving (i.e. impact, vibratory of steel, vibratory of timber); and,
     Environmental data, including but not limited to, the 
following: wind speed and direction, air temperature, humidity, surface 
water temperature, water depth (at the pile and hydrophone locations), 
characteristics of the bottom substrate into which the pile was driven, 
wave height, weather conditions, and other factors that could 
contribute to influencing the airborne and underwater sound levels 
(e.g., aircraft, boats, etc.).
     Sound measurement data shall be provided to NMFS in 
tabular spreadsheet format (Microsoft Excel or similar).

Reporting Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the MOS must immediately 
cease the specified activities and report the incident to the Office of 
Protected Resources (OPR) ([email protected]), NMFS and 
to the Alaska Regional Stranding Coordinator as soon as feasible. If 
the death or injury was clearly caused by the specified activity, MOS 
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 IHA. The MOS 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 impacts or responses (e.g., intensity, duration), 
the context of any impacts or responses (e.g., critical reproductive 
time or location, foraging impacts affecting energetics), 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 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).
    To avoid repetition, our analysis applies to all species listed in 
Table 2 for which take could occur, given that NMFS expects the 
anticipated effects of the pile driving/removal on different marine 
mammal stocks to be similar in nature. Where there are meaningful 
differences between species or stocks, or groups of species, in 
anticipated individual responses to activities, impact of expected take 
on the population due to differences in population status, or impacts 
on habitat, NMFS has identified species-specific factors to inform the 
analysis.
    Pile driving activities associated with the project, as outlined 
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 and Level A harassment from underwater sounds 
generated by pile driving. Potential takes could occur if individuals 
are present in the ensonified zone when these activities are underway.
    No serious injury or mortality would be expected, even in the 
absence of required mitigation measures, given the nature of the 
activities. Further, limited take by Level A harassment is anticipated 
for humpback whales, minke whales, killer whales, harbor porpoise, and 
Steller sea lion due to the application of planned mitigation measures, 
such as shutdown zones that encompass the Level A harassment zones for 
these species and the rarity of these species near the action area. The 
potential for harassment would be minimized through the construction 
method and the implementation of the planned mitigation measures (see 
Mitigation section).
    Take by Level A harassment is authorized for all species, as there 
is potential for these species to be in the area. There is the 
possibility that an animal could enter a Level A harassment zone 
without being detected, and remain within that zone for a duration long 
enough to incur PTS. However, Level A harassment of these species is 
authorized to be conservative. Any take by Level A harassment is 
expected to arise from, at most, a small degree of PTS (i.e., minor 
degradation of hearing capabilities within regions of hearing that 
align most completely with the energy produced by impact pile driving 
such as the low-frequency region below 2 kHz), not severe hearing 
impairment or impairment within the ranges of greatest hearing 
sensitivity. Animals would need to be exposed to higher levels and/or 
longer duration than are expected to occur here in order to incur any 
more than a small degree of PTS.
    Further, the amount of take authorized by Level A harassment is low 
for both marine mammal stocks and species except harbor seals as they 
are common in the area. If hearing impairment occurs, it is most likely 
that

[[Page 60663]]

the affected animal would lose only a few decibels in its hearing 
sensitivity. Due to the small degree anticipated, any PTS potential 
incurred would not be expected to affect the reproductive success or 
survival of any individuals, much less result in adverse impacts on the 
species or stock.
    Additionally, some subset of the individuals that are behaviorally 
harassed could also simultaneously incur some small degree of TTS for a 
short duration of time. However, since the hearing sensitivity of 
individuals that incur TTS is expected to recover completely within 
minutes to hours, it is unlikely that the brief hearing impairment 
would affect the individual's long-term ability to forage and 
communicate with conspecifics, and would therefore not likely impact 
reproduction or survival of any individual marine mammal, let alone 
adversely affect rates of recruitment or survival of the species or 
stock.
    The Level A harassment zones identified in Table 6 are based upon 
an animal's exposure to pile driving of up to 5 steel piles or 18 
timber piles removed per day. Given the short duration to impact drive 
or vibratory install or extract each pile and breaks between pile 
installations (to reset equipment and move piles into place), 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 in the area. If an animal was 
exposed to accumulated sound energy, the resulting PTS would likely be 
small (e.g., PTS onset) at lower frequencies where pile driving energy 
is concentrated, and unlikely to result in impacts to individual 
fitness, reproduction, or survival.
    The nature of the pile driving project precludes the likelihood of 
serious injury or mortality. For all species and stocks, take would 
occur within a limited, confined area (adjacent to the project site) of 
the stock's range. Level A and Level B harassment will be reduced to 
the level of least practicable adverse impact through use of mitigation 
measures described herein. Further, the amount of take authorized is 
small when compared to stock abundance.
    Behavioral responses of marine mammals to pile driving and removal 
in Taiya Inlet are expected to be mild, short term, and temporary. 
Marine mammals within the Level B harassment zones may not show any 
visual cues they are disturbed by activities or they could become 
alert, avoid the area, leave the area, or display other mild responses 
that are not observable, such as changes in vocalization patterns. 
Given that pile driving and removal would occur for only a portion of 
the project's duration, any harassment occurring would be temporary. 
Additionally, many of the species present in region would only be 
present temporarily based on seasonal patterns or during transit 
between other habitats. These temporarily present species would be 
exposed to even smaller periods of noise-generating activity, further 
decreasing the impacts.
    For all species, there are no known Biologically Important Areas 
(BIAs) near the project area that would be impacted by MOS's planned 
activities. While there is a Steller sea lion haulout at the end of 
Taiya inlet at Taiya point, this is approximately 13,300-m from the 
project site. Additionally, there is a rookery at Gran Point, which is 
within designated Steller sea lion critical habitat, though this is 
outside the project area around 24 miles (38.6 km) from Skagway. 
Lastly, there is a summer feeding ground for humpback whales in Lynn 
Canal, however this is outside of Taiya Inlet, and approximately 50 
miles (80.5 km) from Skagway.
    In addition, it is unlikely that minor noise effects in a small, 
localized area of habitat would have any effect on each stock's 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 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 serious injury or mortality is anticipated or 
authorized;
     Authorized Level A harassment would be very small amounts 
and of low degree;
     For all species, Taiya Inlet is a very small and 
peripheral part of their range;
     The intensity of anticipated takes by Level B harassment 
is relatively low for all stocks. Level B harassment would be primarily 
in the form of behavioral disturbance, resulting in avoidance of the 
project areas around where impact or vibratory pile driving is 
occurring, with some low-level TTS that may limit the detection of 
acoustic cues for relatively brief amounts of time in relatively 
confined footprints of the activities;
     Effects on species that serve as prey for marine mammals 
from the activities are expected to be short-term and, therefore, any 
associated impacts on marine mammal feeding are not expected to result 
in significant or long-term consequences for individuals, or to accrue 
to adverse impacts on their populations;
     The ensonified areas are very small relative to the 
overall habitat ranges of all species and stocks, and would not 
adversely affect ESA-designated critical habitat for any species or any 
areas of known biological importance;
     The lack of anticipated significant or long-term negative 
effects to marine mammal habitat; and
     MOS would implement mitigation measures including soft 
starts and shutdown zones to minimize the numbers of marine mammals 
exposed to injurious levels of sound, and to ensure that take by Level 
A harassment is, at most, a small degree of PTS.
    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 monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
activity will have a negligible impact on all affected marine mammal 
species or stocks.

Small Numbers

    As noted previously, only take of small numbers of marine mammals 
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness 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 is authorizing is below one-third of the 
estimated stock abundance for all species. This is likely a 
conservative estimate because we assume all takes are of different 
individual animals, which is likely not the case. Some

[[Page 60664]]

individuals may return multiple times in a day, but PSOs would count 
them as separate takes if they cannot be individually identified.
    The most recent estimate for the Alaska stock of Dall's porpoise 
was 13,110 animals, however this number just accounts for a portion of 
the stock's range. Therefore, the 183 takes of this stock authorized is 
believed to be an even smaller portion of the overall stock abundance.
    Likewise, there is no current or historical estimate of the Alaska 
minke whale stock, but minke whale abundance has been estimated to be 
over 1,000 whales in portions of Alaska (Muto et al., 2022) so the 8 
takes proposed for authorization represent small numbers of this stock. 
Additionally, the range of the Alaska stock of minke whales is 
extensive, stretching from the Canadian Pacific coast to the Chukchi 
Sea, and DOT&PF's project area impacts a small portion of this range. 
Therefore, the eight takes of minke whale proposed for authorization is 
small relative to estimated survey abundance, even if each proposed 
take occurred to a new individual.
    Based on the analysis contained herein of the planned activity 
(including the mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS finds that small numbers of marine mammals 
would be taken relative to the population size of the affected species 
or stocks.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue an IHA, 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 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.
    In the Skagway area, sea lions and harbor seals are available for 
subsistence harvest authorized under the MMPA. The subsistence areas 
used by the Hoonah and Angoon communities are in the vicinity of the 
project area, but will not directly overlap with the project areas. 
During subsistence harvest in Southeast Alaska in 2012, the most recent 
year of available data from the Alaska Department of Fish and Game, 595 
harbor seals were taken, while only 9 sea lions were taken in the 
region (Wolfe et al., 2013). The project at worst may cause short-term 
disturbance to sea lions and harbor seals in the area.
    The activity will take place in Taiya Inlet, and no activities 
overlap with subsistence hunting areas; therefore, there are no 
relevant subsistence uses of marine mammals adversely impacted by this 
action. The planned project is not likely to adversely impact the 
availability of any marine mammal species or stocks that are commonly 
used for subsistence purposes or to impact subsistence harvest of 
marine mammals in the region because:
     Construction activities are localized and temporary;
     Mitigation measures will be implemented to minimize 
disturbance of marine mammals in the action area; and,
     The project will not result in significant changes to 
availability of subsistence resources.
    Based on the description of the specified activity, the measures 
described to minimize adverse effects on the availability of marine 
mammals for subsistence purposes, and the mitigation and monitoring 
measures, NMFS has determined that there will not be an unmitigable 
adverse impact on subsistence uses from MOS's activities.

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA; 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 IHAs, 
NMFS consults internally whenever we plan to authorize take for 
endangered or threatened species, in this case with the Alaska Regional 
Office.
    NMFS is authorizing take of the Mexico-North Pacific stock of 
humpback whale and the Western US stock of Steller sea lion, which are 
listed or include individuals that are listed under the ESA.
    The Permit and Conservation Division completed a Section 7 
consultation with the Alaska Regional Office for the issuance of this 
IHA on August 23, 2023. The Alaska Regional Office's biological opinion 
states that the action is not likely to jeopardize the continued 
existence of the listed species.

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 review our proposed action (i.e., the issuance of an IHA) 
with respect to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or 
mortality) of the Companion Manual for NOAA Administrative Order 216-
6A, which do not individually or 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 determined that 
the issuance of the IHA qualifies to be categorically excluded from 
further NEPA review.

Authorization

    As a result of these determinations, NMFS has issued an IHA to MOS 
for the potential harassment of small numbers of 7 marine mammal 
species incidental to the terminal redevelopment project in Skagway, 
Alaska that includes the previously explained mitigation, monitoring, 
and reporting requirements. The final IHA can be found at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-municipality-skagways-skagway-ore-terminal-redevelopment.

    Dated: August 29, 2023.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2023-19029 Filed 9-1-23; 8:45 am]
BILLING CODE 3510-22-P