[Federal Register Volume 88, Number 192 (Thursday, October 5, 2023)]
[Notices]
[Pages 69145-69158]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-22096]



[[Page 69145]]

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XD241]


Taking of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to City of Cordova Harbor Rebuild 
Project, Cordova, Alaska

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

ACTION: Notice; issuance of an incidental harassment authorization.

-----------------------------------------------------------------------

SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued two incidental harassment authorizations (IHAs) to 
the City of Cordova (Cordova) to incidentally harass marine mammals 
during construction activities associated with a with the City of 
Cordova, Cordova Harbor Rebuild project, in Cordova, Alaska.

DATES: These Authorizations are effective from October 1, 2023 through 
September 30, 2024 and October 1, 2024 through September 30, 2025.

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/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. In case of problems accessing these documents, please call 
the contact listed below.

FOR FURTHER INFORMATION CONTACT: Rachel Wachtendonk, 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 United States (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 February 16, 2023, NMFS received a request from the Cordova for 
two IHAs to take marine mammals incidental to pile driving and removal 
activities associated with the City of Cordova, Cordova Harbor Rebuild 
project, in Cordova, Alaska over the course of 2 years. Following NMFS' 
review of the application, The City of Cordova (Cordova) submitted a 
revised version on April 19, 2023. The application was deemed adequate 
and complete on May 12, 2023. Cordova's request for the first IHA is 
for take of 4 species of marine mammals by Level B harassment and, for 
a subset of these species, Level A harassment. For the second IHA, 
Cordova is requesting take of only Steller sea lion (Eumetopias 
jubatus) and harbor seal (Phocoena phocoena) by Level A and Level B 
harassment. Neither Cordova nor NMFS expect serious injury or mortality 
to result from this activity and, therefore, IHAs are appropriate.
    There are no changes from the proposed IHAs to the final IHAs.

Description of Activity

    Cordova plans to replace existing structures in the Cordova Harbor 
in Cordova, Alaska. Over the course of 2 years spanning September 2023-
April 2024 and September 2024-April 2025, Cordova will use a variety of 
methods, including vibratory, impact, and down-the-hole (DTH) pile 
driving to remove existing piles and to install new ones.
    Phase I will involve the removal of existing piles, the 
installation and removal of temporary piles, and the installation of 
permanent piles in the south harbor. During Phase I, 130 timber (12-
inch (in) diameter; 0.3-meter (m) diameter) and 61 old steel (12-in 
(0.3-m) diameter) piles will be removed. Once the existing piles are 
removed, 155 16-in (0.4-m), 70 18-in (0.5-m), and 30 30-in (0.8-m) 
permanent steel piles will be installed. The installation and removal 
of 61 temporary 24-in (0.6-m) steel pipe piles will be completed to 
support permanent pile installation. Vibratory hammers, impact hammers, 
and DTH drilling will be used for the installation and removal of all 
piles. Piles will be removed by dead-pull or vibratory methods. The 
installation and removal of temporary piles will be conducted using 
vibratory hammers. All permanent piles will be initially installed with 
a vibratory hammer. After vibratory driving, if needed, piles will be 
impacted into the bedrock with an impact hammer. For some piles, a DTH 
drill will be needed to drive piles the final few inches of embedment.
    Phase II will involve the removal of existing piles, the 
installation and removal of temporary piles, and the installation of 
permanent piles in the north and south harbor. During Phase II, 268 12-
in (0.3-m) timber piles will be removed. Then, 24 24-in (0.6-m) steel 
piles, 80 steel H-piles, and 80 steel sheet piles will be installed. 
The installation and removal of 31 temporary 24-in (0.6-m) steel pipe 
piles will be completed to support permanent pile installation. As in 
Phase I, vibratory hammers, impact hammers, and DTH drilling will be 
used for the installation and removal of all piles. Piles will be 
removed by dead-pull or vibratory methods. The installation and removal 
of temporary piles will be conducted using vibratory hammers. All 
permanent piles would be initially installed with a vibratory hammer. 
After vibratory driving, if needed, piles will be impacted into the 
bedrock with an impact hammer. For some piles, a DTH drill will be 
needed to drive piles the final few inches of embedment.
    A further detailed description of the planned construction project 
is provided in the Federal Register notice for the proposed IHAs (88 FR 
45149, July 14, 2023). Since that time, no changes have been made to 
the planned activities. Therefore, a detailed description is not 
provided here. 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).

[[Page 69146]]

Comments and Responses

    A notice of NMFS' proposal to issue two IHAs to Cordova was 
published in the Federal Register on July 14, 2023 (88 FR 45149). That 
notice described, in detail, Cordova's activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals. During the 30-day public comment period, no 
public comments were received.

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 1 lists all species or stocks for which take is expected and 
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' Alaska Marine Mammal SARs. All values presented in Table 1 are 
the most recent available at the time of publication (including from 
the 2022 SARs) and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

                                            Table 1--Species Likely Impacted by the Specified Activities \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/MMPA  status;   Stock abundance  (CV,
             Common name                  Scientific name               Stock            strategic  (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \2\          abundance survey) \3\               SI \4\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Killer whale....................  Orcinus orca...........  Alaska Resident........  -/-; N              1,920 (N/A, 1,920,             19        1.3
                                                                                                             2019).
                                                               Gulf of Alaska/Aleutian  -/-; N              587 (N/A, 587, 2012)..        5.9        0.8
                                                                Islands/Bering Sea
                                                                Transient.
                                                               AT1 Transient..........  -/D; N              7 (N/A, 7, 2019)......        0.1          0
Family Phocoenidae (porpoises):
    Dall's porpoise.................  Phocoenoides dalli.....  Alaska.................  -/-; N              UND (UND, UND, 2015)          UND         37
                                                                                                             \5\.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Order Carnivora--Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    Steller sea lion................  Eumetopias jubatus.....  Western DPS............  E/D; Y              52,932 (N/A, 52,932,          318        254
                                                                                                             2019).
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Prince William Sound...  -/-; N              44,756 (N/A, 41,776,         1253        413
                                                                                                             2015).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy
  (https://www.marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies; Committee on Taxonomy, 2022).
\2\ 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.
\3\ NMFS marine mammal stock assessment reports online at: https://www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum
  estimate of stock abundance. In some cases, CV is not applicable.
\4\ 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, vessel 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.
\5\ Population estimate of 13,110 based on surveys from western Prince William Sound, as abundance estimates for the Alaska stock are more than 8 years
  old and are no longer considered reliable (Muto et al., 2022). This population estimate will be used for small numbers calculations.

    As indicated above, all four species (with six managed stocks) in 
Table 1 temporally and spatially co-occur with the activity to the 
degree that take is reasonably likely to occur. All species that could 
potentially occur in the planned project areas are included in Table 10 
of the IHA application. While northern fur seal, Pacific white-sided 
dolphin, harbor porpoise, humpback whale, fin whale, minke whale, and 
gray whale have been documented in Prince William Sound, the temporal 
and/or spatial occurrence of these species is such that take is not 
expected to occur, and they are not discussed further beyond the 
explanation provided here. These species are all considered to be rare 
(no sightings in recent years) or very rare (no local knowledge of 
sightings within the project vicinity)

[[Page 69147]]

within Orca Bay according to the Prince William Sound Science Center in 
Cordova (Prince William Sound Science Center, 2022; Schinella, 2022). 
Given the shallow depths of the waters surrounding Cordova Harbor, it 
would also be unusual for many of these species to enter the project 
area. The take of these species has not been requested nor authorized 
and these species are not considered further in this document.
    A detailed description of the species likely to be affected by 
Cordova'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 IHAs (88 FR 45149, July 14, 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. 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 associated hearing ranges are provided in Table 2.

                  Table 2--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           150 Hz to 160 kHz.
 (dolphins, 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)     50 Hz to 86 kHz.
 (true seals).
Otariid pinnipeds (OW) (underwater)    60 Hz to 39 kHz.
 (sea 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 a ~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 Cordova'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 IHAs (88 FR 45149, July 14, 2023) included a discussion of the 
effects of anthropogenic noise on marine mammals and the potential 
effects of underwater noise from Cordova'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 IHAs (88 FR 
45149, July 14, 2023).

Estimated Take of Marine Mammals

    This section provides an estimate of the number of incidental takes 
authorized through these IHAs, 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 will primarily be by Level B harassment, as use of 
the acoustic sources (i.e., vibratory or impact pile driving and DTH 
drilling) 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, primarily for 
Dall's porpoise and harbor seals, due to the cryptic nature of these 
species in context of larger predicted auditory injury zones. Auditory 
injury is unlikely to occur for mid-frequency species and otariids, 
based on the likelihood of the species in the action area, the ability 
to monitor the entire smaller shutdown zone, and because of the 
expected ease of detection for the former groups. 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

[[Page 69148]]

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 would be behaviorally 
harassed or incur some degree of permanent hearing impairment; (2) the 
area or volume of water that would 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). Thresholds have also been 
developed identifying the received level of in-air sound above which 
exposed pinnipeds would likely be behaviorally harassed.
    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. For in-air sounds, NMFS predicts that harbor 
seals exposed above received levels of 90 dB re 20 [mu]Pa (RMS) would 
be behaviorally harassed, and other pinnipeds would be harassed when 
exposed above 100 dB re 20 [mu]Pa (RMS). 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 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.
    Cordova's planned activity includes the use of continuous 
(vibratory hammer and DTH drilling) and impulsive (DTH drilling and 
impact pile driving) sources, and therefore the 120- and 160-dB re 1 
[mu]Pa (RMS) thresholds 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). Cordova's 
planned activity includes the use of impulsive (impact pile driving and 
DTH drilling) and non-impulsive (vibratory hammer and DTH drilling) 
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 3--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[mu]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.


[[Page 69149]]

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, vibratory 
pile driving and removal, and DTH).
    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 4). This analysis uses the practical spreading loss model, a 
standard assumption regarding sound propagation for similar 
environments, to estimate transmission of sound through water. For this 
analysis, the transmission loss factor of 15 (4.5 dB per doubling of 
distance) is used. A weighting adjustment factor of 2.5 or 2, a 
standard default value for vibratory pile driving and removal or impact 
driving and DTH respectively, were used to calculate Level A harassment 
areas.
    NMFS recommends treating DTH systems as both impulsive and 
continuous, non-impulsive sound source types simultaneously. Thus, 
impulsive thresholds are used to evaluate Level A harassment, and 
continuous thresholds are used to evaluate Level B harassment. With 
regards to DTH mono-hammers, NMFS recommends proxy levels for Level A 
harassment based on available data regarding DTH systems of similar 
sized piles and holes (Denes et al., 2019; Guan and Miner, 2020; Reyff 
and Heyvaert, 2019; Reyff, 2020; Heyvaert and Reyff, 2021).

               Table 4--Estimated Underwater Proxy Source Levels for Pile Installation and Removal
----------------------------------------------------------------------------------------------------------------
                                                   Proxy source levels (dB) at 10 m
          Pile type               Phase    ------------------------------------------------       Reference
                                                 Peak             RMS             SEL
----------------------------------------------------------------------------------------------------------------
                                             Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
12- to 24-in timber pile       I, II        ..............             162  ..............  Greenbusch et al.,
 removal.                                                                                    2018; CALTRANS,
                                                                                             2020.
12- to 24-in steel pile        I            ..............             161  ..............  NAVFAC (2013, 2015).
 removal.
24-in steel template pile      I, II        ..............                  ..............  ....................
 install/removal.
16-in steel pile.............  I            ..............                  ..............  ....................
18-in steel pile.............  I            ..............                  ..............  ....................
24-in steel pile.............  II           ..............                  ..............  ....................
30-in steel pile.............  I            ..............           161.9  ..............  Denes et al., 2016.
Steel H-pile.................  II           ..............             165  ..............  CALTRANS, 2015.
Steel sheet pile.............  II           ..............             162  ..............  Buehler et al.,
                                                                                             2015.
----------------------------------------------------------------------------------------------------------------
                                               Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
16-in steel pile.............  I                     192.8           181.1           168.3  Denes et al., 2016.
18-in steel pile.............  I            ..............  ..............  ..............  ....................
24-in steel pile.............  II           ..............  ..............  ..............  ....................
30-in steel pile.............  I                       210             190             177  NMFS 2023 analysis
                                                                                             *.
Steel H-pile.................  II                      200             177             170  CALTRANS, 2015.
Steel sheet pile.............  II                      205             190             180  CALTRANS, 2015.
----------------------------------------------------------------------------------------------------------------
                                                  DTH Drilling
----------------------------------------------------------------------------------------------------------------
16-in steel pile.............  I            ..............             167             159  Heyvaert and Reyff,
                                                                                             2021.
18- to 24-in steel pile......  I, II        ..............  ..............  ..............  ....................
30-in steel pile.............  I            ..............             174             164  Denes et al., 2019);
                                                                                             Reyff and Heyvaert,
                                                                                             2019; Reyff, 2020.
Steel H-pile.................  II           ..............  ..............  ..............  ....................
----------------------------------------------------------------------------------------------------------------
Note: SEL= sound exposure level; RMS= root mean square.
* NMFS used the mean of regionally relevant measurements to determine suitable proxy source values for these
  pile types. Projects included in the analysis were Navy (2012, 2013) and Miner (2020), following the
  methodology of Navy (2015).


                 Table 5--Estimated In-Air Proxy Source Levels for Pile Installation and Removal
----------------------------------------------------------------------------------------------------------------
                                                                     Proxy source
                                                                   levels  (dB) at
                Pile type                          Phase                 15 m                 Reference
                                                                 -------------------
                                                                         RMS
----------------------------------------------------------------------------------------------------------------
                                             Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
24-in steel template pile install/        I                                   103.2  Laughlin, 2010.
 removal.
18-in steel pile........................  ......................  .................  ...........................
Steel H-pile............................  ......................  .................  ...........................
----------------------------------------------------------------------------------------------------------------

[[Page 69150]]

 
                                               Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
18-in steel pile........................  I                                     101  Ghebreghzabiher et al.,
                                                                                      2017.
Steel H-pile............................  ......................  .................  ...........................
----------------------------------------------------------------------------------------------------------------
                                                DTH Drilling \1\
----------------------------------------------------------------------------------------------------------------
18-in steel pile........................  I                                     101  Ghebreghzabiher et al.,
                                                                                      2017.
Steel H-pile............................  ......................  .................  ...........................
----------------------------------------------------------------------------------------------------------------
Note: SEL= sound exposure level; RMS= root mean square.
\1\ We conservatively assume that the proxy value for DTH driving is the same as for impact driving.

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 spherical and 
cylindrical spreading loss conditions, which is the most appropriate 
assumption for Cordova's planned underwater activities. The Level B 
harassment zones and approximate amount of area ensonified for the 
planned underwater activities are shown in Table 6. The Level B 
harassment zones for the planned upland pile driving activities that 
may generate airborne noise are shown in Table 5.

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) are presented in Tables 1 and 2 in the Federal 
Register Notice of the proposed IHAs (88 FR 45149, July 14, 2023). The 
maximum RMS SPL, sound exposure level (SEL), and resulting isopleths 
are reported in Tables 4, 5, and 6.

                                      Table 6--Level A and Level B Harassment Isopleths for Pile Driving Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Distances to Level A and Level B thresholds (m)
                                                 ----------------------------------------------------------------                      Ensonified area 1
            Pile type                  Phase                                  Level A                                   Level B         2 for  Level B
                                                 ----------------------------------------------------------------                           (km\2\)
                                                        MF              HF            Phocid          Otariid
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Vibratory Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
12- to 24-in timber pile removal  I, II                      1.8            30.5            12.5             0.9  6,309.6...........  125.
12- to 24-in steel pile removal.  I                          1.6            26.1            10.7             0.8  5,411.7...........  92.
24-in steel template pile         I, II                      0.9            14.2             5.8             0.4                      ..................
 install/removal.
16-in steel pile................  I                          1.1            18.6             7.6             0.5                      ..................
18-in steel pile................  I                          1.4            22.5             9.3             0.7                      ..................
24-in steel pile................  II              ..............  ..............  ..............  ..............                      ..................
30-in steel pile................  I                          1.4            24.1             9.9             0.7  6,213.5...........  121.2.
Steel H-pile....................  II                         1.1            18.7             7.7             0.5  10,000............  314.

[[Page 69151]]

 
Steel sheet pile................  II                         0.7            11.8             4.8             0.3  6,310.............  125.
In-air pile installation/removal  I               ..............  ..............  ..............  ..............  68.6 (Phocid)/22.8  0.01 (Phocid)/
                                                                                                                   (Otariid).          0.002 (Otariid).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Impact Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
16-in steel pile................  I                          4.7           158.8            71.4             5.2  255...............  0.2.
18-in steel pile................  I                                                                                                   ..................
24-in steel pile................  II              ..............  ..............  ..............  ..............  ..................  ..................
30-in steel pile................  I                         23.6           791.3           355.5            25.9  1,000.............  3.14.
Steel H-pile....................  II                        12.1           405.3           182.1            13.3  341.5.............  0.37.
Steel sheet pile................  II                        56.2          1881.2           845.2            61.5  1,000.............  3.14.
In-air pile installation/removal  I               ..............  ..............  ..............  ..............  53.2 (Phocid)/16.8  0.009 (Phocid)/
                                                                                                                   (Otariid).          0.0009 (Otariid).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      DTH Drilling
--------------------------------------------------------------------------------------------------------------------------------------------------------
16-in steel pile................  I                         32.1          1075.7           483.3            35.2  13,593.6..........  580.2.
18- to 24-in steel pile.........  I,II            ..............  ..............  ..............  ..............                      ..................
30-in steel pile................  I                         61.3        2,052.20             922            67.1  39,810.7..........  4976.6.
Steel H-pile....................  II              ..............  ..............  ..............  ..............                      ..................
In-air pile installation/removal  I               ..............  ..............  ..............  ..............  53.2 (Phocid)/16.8  0.009 (Phocid)/
                                                                                                                   (Otariid).          0.0009 (Otariid).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\Areas were calculated based on areas of a circle with the specified radius from Table 4 and 5 and realized ensonified areas will be smaller due to
  truncation by land masses.
\2\The ensonified area within Cordova Harbor will be no more than 0.19 kilometers\2\ (km\2\).

Marine Mammal Occurrence

    In this section we provide information about the occurrence of 
marine mammals, including presence, density, local knowledge, or other 
relevant information which will inform the take calculations.
    Daily occurrence probability of each marine mammal species in the 
action area is based on consultation with local researchers and marine 
professionals. Occurrence probability estimates are based on 
conservative density approximations for each species and factor in 
historic data of occurrence, seasonality, and group size in Orca Bay, 
Orca Inlet, and/or Prince William Sound. A summary of planned take is 
shown in Table 7. To accurately describe species occurrence near the 
action area, marine mammals were described as either common (multiple 
sightings every month, could occur each day), frequent (multiple 
sightings every year, could occur each month), or infrequent (few 
sightings every year, could occur each month).

                       Table 7--Estimated Occurrence of Group Sightings of Marine Mammals
----------------------------------------------------------------------------------------------------------------
             Species                    Frequency           Seasonality           Occurrence      Group size \a\
----------------------------------------------------------------------------------------------------------------
Steller sea lion:
    (within harbor)..............  Common.............  Year-round.........  1 group per day....         \b\ 4.1
    (outside harbor).............  Common.............  Year-round.........  2 groups per day...         \b\ 4.1
Harbor seal:
    (within harbor)..............  Frequent...........  Year-round.........  1 group per day....         \c\ 3.5
    (outside harbor).............  Common.............  Year-round.........  2 groups per day...         \c\ 3.5
Killer whale.....................  Infrequent.........  Year-round.........  1 group per 10 days          \d\ 14
Dall's porpoise..................  Infrequent.........  Year-round.........  1 group per 10 days         \e\ 4.3
----------------------------------------------------------------------------------------------------------------
\a\ Group size was averaged from seasonal data (Steller sea lions and harbor seals), pod size (killer whales),
  and observational data (Dall's porpoise) for more information see application.
\b\ Leonard and Wisdom, 2020; Sigler et al., 2017.
\c\ ADF&G, 2022a.
\d\ Muto et al., 2022.
\e\ Moran et al., 2018.

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 are authorized.
    For total underwater take estimate, the daily occurrence 
probability for a species was multiplied by the estimated group size 
and by the number of days of each type of pile driving activity. Group 
size is based on the best available published research for these 
species and their presence in this area.


[[Page 69152]]


Estimated take = Group size x Groups per day x Days of pile driving 
activity

    Take of pinnipeds by Level B harassment due to airborne noise was 
calculated based on the proportion of area within the harbor likely to 
be ensonified above the thresholds for harbor seals and other 
pinnipeds, respectively. The percent of the harbor ensonified was then 
multiplied by the number of days of pile driving, the group size, and 
groups per day, as done for underwater take estimates. The total 
numbers of takes by Level B harassment due to airborne noise authorized 
for harbor seal and Steller sea lion are seven and zero, respectively.
    Take by Level A harassment is authorized for Steller sea lions and 
harbor seals given that these species are known to spend extended 
periods of time within Cordova Harbor and most Level A harassment 
isopleths are contained within Cordova Harbor. The take by Level A 
harassment calculations are based on lower daily occurrence estimates 
for each species than take by Level B harassment calculations based on 
input from marine professionals in the community about their presence 
in within the smaller ensonified zone of the harbor (Table 7; Greenwood 
2022). Take by Level A harassment is also authorized for Dall's 
porpoise for impact driving of sheet piles and DTH drilling of 30 in 
and H-piles as it is not practicable to observe and shut down for 
porpoises throughout the entire Level A harassment zone (1,885 m for 
impact driving and 2,050 m for DTH drilling). Additionally, Level A 
harassment isopleths for most hearing groups and pile types were less 
than 10 m (Table 6) which is the minimum shutdown zone for this project 
(see Mitigation). Because the Level A harassment isopleths for those 
piles are within the minimum 10-m shutdown zone, no takes by Level A 
harassment are expected to occur from those activities, and therefore 
the predicted take by Level A harassment were removed from the total 
take calculations (Table 8).
    During Phase II, killer whale and Dall's porpoise are not expected 
to occur within any harassment zones due to the relatively shallow 
water that will be ensonified (south of Spike Island into tidal mud 
flats) and therefore no take is authorized for these species.

                       Table 8--Take of Marine Mammals by Level A and Level B Harassment and Percent of Stock To Be Taken by Phase
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          Authorized take
                  Species                             Stock/DPS          ------------------------------------------------ Stock size \1\    Percent of
                                                                              Level A         Level B       Total take                         stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Phase I
--------------------------------------------------------------------------------------------------------------------------------------------------------
Steller sea lion..........................  Western DPS.................             107             788             895          52,932            1.69
Harbor seal...............................  Prince William Sound........             154             681             835          44,756            1.87
Killer whale \2\..........................  Alaska Resident.............  ..............              83              83           1,920            4.35
                                            Gulf of Alaska/Aleutian       ..............              26              26             587            4.35
                                             Islands/Bering Sea
                                             Transient.
Dall's porpoise...........................  Alaska......................              10              32              42          13,110            0.32
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Phase II
--------------------------------------------------------------------------------------------------------------------------------------------------------
Steller sea lion..........................  Western DPS.................              98             730             828          52,932            1.56
Harbor seal...............................  Prince William Sound........             133             623             756          44,756            1.69
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Stock size comes from the most recent SARs except for Dall's porpoise whose stock estimate is based on surveys from western Prince William Sound
  only, as abundance estimates for the Alaska stock are more than 8 years old and no longer considered reliable (Muto et al., 2022).
\2\ AT1 transient stock take calculation resulted in 0.3 takes, therefore no takes were requested or are authorized.

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. 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.

Mitigation Measures

    Cordova must follow mitigation measures as specified below:
     Ensure that construction supervisors and crews, the 
monitoring team, and relevant Cordova staff are trained prior to the 
start of all pile driving and DTH drilling 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 Protected Species Observers (PSOs) and establish 
monitoring locations as described in the

[[Page 69153]]

application and the IHAs. The Holder must monitor the project area to 
the maximum extent possible based on the required number of PSOs, 
required monitoring locations, and environmental conditions. For all 
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 and DTH drilling activities will ensure that the entire 
shutdown zone is visible during pile installation;
     Monitoring must take place from 30 minutes prior to 
initiation of pile driving or DTH drilling activity (i.e., pre-
clearance monitoring) through 30 minutes post-completion of pile 
driving or DTH drilling 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 and DTH drilling may commence following 30 minutes of 
observation when the determination is made that the shutdown zones are 
clear of marine mammals;
     Cordova 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 and DTH drilling 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 the applicant, in water activities will take 
place only between civil dawn and civil dusk when PSOs can effectively 
monitor for the presence of marine mammals; during conditions with a 
Beaufort Sea State of 4 or less. Pile driving and DTH drilling may 
continue for up to 30 minutes after sunset during evening civil 
twilight, as necessary to secure a pile for safety prior to 
demobilization during this time. The length of the post-activity 
monitoring period may be reduced if darkness precludes visibility of 
the shutdown and monitoring zones.

Shutdown Zones

    Cordova will establish shutdown zones for all pile driving and DTH 
drilling activities. The purpose of a shutdown zone is generally to 
define an area within which shutdown of the activity will occur upon 
sighting of a marine mammal (or in anticipation of an animal entering 
the defined area). Shutdown zones will be based upon the Level A 
harassment isopleth 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 m, work will stop and vessels will 
reduce speed to the minimum level required to maintain steerage and 
safe working conditions. A 10-m shutdown zone serves 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, 
construction activities including in-water work will continue and the 
animal's presence within the estimated harassment zone will be 
documented.
    Cordova 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 these IHAs 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 will result in an imminent 
safety concern, as determined by Cordova 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.

                                                         Table 9--Shutdown and Monitoring Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  Minimum shutdown zone (m)
               Pile type                         Phase        ----------------------------------------------------------------    Monitoring zone (m)
                                                                     MF              HF            Phocid          Otariid
--------------------------------------------------------------------------------------------------------------------------------------------------------
Barge movements, pile positioning, etc.  I, II                             10              10              10              10  10.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 Vibratory Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
12- to 24-in timber pile removal.......  I, II                             10              35              25              10  6,310.
12- to 24-in steel pile removal........  I                                 10              35              20              10  5,425.
24-in steel template pile install/       I, II                             10              25              10              10  5,425.
 removal.
16- to 24-in steel pile................
30-in steel pile.......................  I                                 10              25              10              10  6,225.
Steel H-pile...........................  II                                10              35              25              10  10,000.
Steel sheet pile.......................  II                                10              25              10              10  6,310.

[[Page 69154]]

 
In-air pile install/removal............  I                     ..............  ..............  ..............  ..............  70 (phocids)/25
                                                                                                                                (otariids).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Impact Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
16- to 24-in steel pile................  I                                 10             185              75              10  255.
30-in steel pile.......................  I                                 25             800             360              25  1,000.
Steel H-pile...........................  II                                25             410             185              25  350.
Steel sheet pile.......................  II                                75           1,000             500              75  1,000.
In-air pile install....................  I                     ..............  ..............  ..............  ..............  55 (phocids)/20
                                                                                                                                (otariids).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      DTH Drilling
--------------------------------------------------------------------------------------------------------------------------------------------------------
16- to 24-in pile......................  I, II                             35           1,000             500              40  13,594.
30-in pile.............................  I                                 75           1,000             500              75  39,811.
Steel H-pile...........................  II                                75           1,000             500              75  39,811.
In-air pile install....................  I                     ..............  ..............  ..............  ..............  55 (phocids)/20
                                                                                                                                (otariids).
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 or DTH drilling 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 would 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 the applicant's planned measures NMFS 
has determined that the mitigation measures provide the means of 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

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,

[[Page 69155]]

     Mitigation and monitoring effectiveness.

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
conditions in this section and the IHAs. Marine mammal monitoring 
during pile driving activities will be conducted by PSOs meeting NMFS' 
following requirements:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods will be used;
     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;
     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;
     Cordova must employ up to five PSOs 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;
     Cordova must establish monitoring locations with the best 
views of monitoring zones as described in the IHAs and Application;
     Up to five monitors will be used at a time depending on 
the size of the monitoring area. PSOs will 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 impact hammering monitoring zone and the 
Level A harassment Shutdown Zones. 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;
     During work in the south harbor, up to three PSOs will be 
stationed at the following locations: along the south harbor parking 
area, on the Breakwater Trail, and at a viewpoint along New England 
Cannery Road; and
     During work in the north harbor, up to five PSOs will be 
stationed at the following locations: along the north harbor parking 
area, on the Breakwater Trail, at the viewpoint along the shore near 
Saddle Point, at a viewpoint along Whitshed Road, and on a vessel in 
Orca Inlet.
    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.
    Cordova shall conduct briefings between construction supervisors 
and crews, PSOs, Cordova 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.

Reporting

    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities for each IHA, 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:
    (1) Dates and times (begin and end) of all marine mammal 
monitoring;
    (2) 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, vibratory, or DTH drilling) and the total 
equipment duration for vibratory removal for each pile or total number 
of strikes for each pile (impact driving);
    (3) PSO locations during marine mammal monitoring;
    (4) 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; and
    (5) Upon observation of a marine mammal, the following information:
    (a) Name of PSO who sighted the animal(s) and PSO location and 
activity at the time of sighting;
    (b) Time of sighting;
    (c) 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;
    (d) 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);
    (e) Estimated number of animals (min/max/best estimate);
    (f) Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, sex class, etc.);
    (g) Animal's closest point of approach and estimated time spent 
within the harassment zone;
    (h) 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);
    (i) Number of marine mammals detected within the harassment zones 
and shutdown zones; by species; and
    (j) 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.
    If no comments are received from NMFS within 30 days, the draft 
reports

[[Page 69156]]

will constitute the final reports. If comments are received, a final 
report addressing NMFS comments must be submitted within 30 days after 
receipt of comments.

Reporting Injured or Dead Marine Mammals

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

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any 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, the discussion of our analysis applies to all 
the species listed in Table 1, given that the anticipated effects of 
this activity on these different marine mammal stocks are expected to 
be similar. There is little information about the nature or severity of 
the impacts, or the size, status, or structure of any of these species 
or stocks that would lead to a different analysis for this activity. 
Also, because both the number and nature of the estimated takes 
anticipated to occur are identical in Phase I and Phase II, the 
analysis below applies to each of the IHAs.
    Pile driving and DTH drilling 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, for some 
species, 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 is expected, even in the absence of 
required mitigation measures, given the nature of the activities. 
Further, no take by Level A harassment is anticipated for killer whales 
due to the application of planned mitigation measures, such as shutdown 
zones that encompass the Level A harassment zones for the species, the 
rarity of the species near the action area, and the shallow depths of 
the harbor. The potential for harassment will 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 three species (Steller 
sea lion, harbor seal, and Dall's porpoise) as the Level A harassment 
isopleths exceed the size of the shutdown zones for specific 
construction scenarios. Additionally, the two pinniped species are 
common in and around the action area. Therefore, there is the 
possibility that an animal could enter a Level A harassment zone and 
remain within that zone for a duration long enough to incur PTS. Take 
by Level A harassment of these species is therefore authorized. 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 
kilohertz (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 authorized take by Level A harassment is 
very low for the marine mammal stocks and species. If hearing 
impairment occurs, it is most likely that 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.
    The Level A harassment zones identified in Table 6 are based upon 
an animal exposed to pile driving or DTH drilling of several piles per 
day (up to 25 piles per day for vibratory removal, 10 piles per day of 
vibratory installation, 6 piles per day of impact driving, and 4 piles 
per day of DTH drilling). Given the short duration to impact drive or 
vibratory install or extract, or use DTH drilling, each pile and break 
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 patterns 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.
    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

[[Page 69157]]

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 will 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 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. Take by 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 extremely small when compared to stock abundance.
    Behavioral responses of marine mammals to pile driving, pile 
removal, and DTH drilling in Cordova Harbor and the surrounding Orca 
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, pile removal, and DTH drilling are temporary activities and 
effects will cease when equipment is not operating, any harassment 
occurring will be temporary. Additionally, many of the species present 
in region will only be present temporarily based on seasonal patterns 
or during transit between other habitats. These species will be exposed 
to even smaller periods of noise-generating activity, further 
decreasing the impacts.
    The same regions are also a part of the western distinct population 
segment (DPS) Steller sea lion ESA critical habitat. While Steller sea 
lions are common in the project area, there are no essential physical 
and biological habitat features, such as haulouts or rookeries, within 
the planned project area. The nearest haulout and rookery are over 30 
km away from the planned project area. Therefore, the planned project 
is not expected to have significant adverse effects on the critical 
habitat of Wester DPS Steller sea lions. No areas of specific 
biological importance (e.g., ESA critical habitat, other BIAs, or other 
areas) for any other species are known to co-occur with the project 
area.
    In addition, it is unlikely that minor noise effects in a small, 
localized area of habitat will 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 any of the species or stocks 
through effects on annual rates of recruitment or survival:
     No serious injury or mortality is anticipated or 
authorized;
     Take by Level A harassment will be very small amounts and 
of low degree;
     Take by Level A harassment is authorized only for Steller 
sea lions, harbor seals, and Dall's porpoise;
     For all species, the Orca Inlet and the Cordova Harbor is 
a very small and peripheral part of their range;
     Anticipated takes by Level B harassment are relatively low 
for all stocks. Level B harassment will 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 will 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
     Cordova will 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, specific to 
each of the 2 consecutive years of planned 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 plans to authorize, specific to each of the 
2 consecutive years of planned activity, is below one-third of the 
estimated stock abundance for all species (in fact, take of individuals 
is less than 5 percent of the abundance of the affected stocks, see 
Table 8). This is likely a conservative estimate because we assume all 
takes are of different individual animals, which is likely not the 
case. Some individuals may return multiple times in a day, but PSOs 
will 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 accounts for only a portion of 
the stock's range. Therefore, the 42 authorized takes (including 10 
Level A takes) of this stock are believed to be an even smaller portion 
of the overall stock abundance.
    Based on the analysis contained herein of the planned activity 
(including the mitigation and monitoring measures) and the anticipated 
take of marine mammals, for each of the 2 consecutive years of planned 
activity, NMFS finds that small numbers of marine mammals would be 
taken

[[Page 69158]]

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.
    The Alutiiq and Eyak people of Prince William Sound traditionally 
harvested marine mammals, however the last recorded subsistence harvest 
in Cordova was in 2014 as part of a regional effort to update the 
status of subsistence uses in Exxon Valdez Oil Spill communities, 
during which no marine mammals were harvested in Cordova (Fall and 
Zimpelman 2016).
    In the decades since the Exxon Valdez Oil Spill, there have been 
declines in the number of households hunting and harvesting larger 
marine mammals in Prince William Sound. Surveys gathering subsistence 
data found that 10 percent or fewer households harvest or use harbor 
seals or sea lions (Poe et al., 2010). Subsistence hunters in Prince 
William Sound report having to travel farther from their home 
communities to be successful when harvesting marine mammals (Keating et 
al., 2020).
    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:
     There is no recent recorded subsistence harvest of marine 
mammals in the area;
     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 planned mitigation and 
monitoring measures, NMFS has determined that there will not be an 
unmitigable adverse impact on subsistence uses from Cordova's planned 
activities.

Endangered Species Act

    There is one marine mammal species (western DPS Steller sea lion) 
with confirmed occurrence in the project area that is listed as 
endangered under the ESA. The NMFS Alaska Regional Office issued a 
Biological Opinion on September 28, 2023 under section 7 of the ESA on 
the issuance of two IHAs to Cordova under section 101(a)(5)(D) of the 
MMPA by the NMFS Office of Protected Resources. The Biological Opinion 
concluded that this action is not likely to jeopardize the continued 
existence of Western Distinct Population Segment (DPS) Steller sea 
lions. In addition, the proposed action is not likely to adversely 
affect Western North Pacific DPS humpback whales, Mexico DPS humpback 
whales, fin whales, or Steller sea lion critical habitat.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must evaluate our proposed action (i.e., the issuance of two IHAs) 
and alternatives 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 NAO 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 has determined that the 
issuance of these IHAs qualifies to be categorically excluded from 
further NEPA review.

Authorizations

    NMFS has issued two consecutive IHAs to Cordova for the potential 
harassment of small numbers of marine mammal species incidental to the 
Cordova Harbor Rebuild project, in Cordova, Alaska, that includes the 
previously explained mitigation, monitoring and reporting requirements.

    Dated: September 29, 2023.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2023-22096 Filed 10-4-23; 8:45 am]
BILLING CODE 3510-22-P