[Federal Register Volume 88, Number 218 (Tuesday, November 14, 2023)]
[Notices]
[Pages 77985-77996]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-24980]


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

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XD502]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to U.S. Coast Guard Construction in 
Astoria, Oregon

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 an Incidental Harassment Authorization (IHA) to 
the United States Coast Guard (USCG) to incidentally harass marine 
mammals during pile driving activities associated with East Tongue 
Point (ETP) construction project in Astoria, Oregon.

DATES: The Authorization is effective from November 6, 2023 through 
November 5, 2024.

ADDRESSES: Electronic copies of the application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained online at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-united-states-coast-guards-construction-astoria-oregon. In case of problems accessing these documents, please 
call the contact listed above.

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

SUPPLEMENTARY INFORMATION: 

Background

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

Summary of Request

    On April 22, 2022, NMFS received a request from the USCG for an IHA 
to take marine mammals incidental to pile driving activity associated 
with the ETP construction in Astoria, Oregon. Following NMFS' review of 
the application, we received a revised version of the application on 
June 27, 2022. After finalizing construction details, the USCG 
submitted another revised version on May 26, 2023, followed by a final 
revised version on July 24, 2023, which was deemed adequate and 
complete on August 1, 2023. The proposed IHA was published for public 
comment on September 27, 2023. USCG's request is for take of harbor 
seal, California sea lion, Steller sea lion and harbor porpoise by 
Level B harassment and, for harbor seal and harbor porpoise, Level A 
harassment. Neither USCG nor NMFS expect serious injury or mortality to 
result from this activity and, therefore, an IHA is

[[Page 77986]]

appropriate. There are no changes from the proposed IHA to the final 
IHA.

Description of Activity

Overview

    The USCG requested an IHA to homeport multiple new Fast Response 
Cutters (FRC) to support USCG District 13 at ETP in Astoria, OR. This 
three-phased project entails both onshore and in-water construction 
activities to remove old piles, construct and improve facilities 
necessary for the long-term support of the FRC's and USCG mission. 
Phase 1 includes pile removal and demolition, dredging and shoreline 
rock improvements, phase 2 includes all pile driving and in water 
construction, and phase 3 includes all overwater and upland 
construction.
    The purpose of the project is to improve and construct waterside 
and landslide facilities that will meet homeporting requirements of the 
FRCs. This includes the availability of logistics and support amenities 
for personnel, the ability of the new FRC docks/floats to accommodate 
the FRCs with all necessary operations on the boat while it is 
stationary at the dock, and the ability of the facility to provide for 
a long-term USCG presence for the economic life of its assets. 
Facilities at ETP are aged, outdated, and will require improvements to 
meet homeporting requirements.
    Of the stages of this project, the only part that may result in 
Level A and Level B harassment, and further analyzed in this notice is 
the in-water construction activities associated with impact pile 
driving (Phase 2). The USCG proposes installation of 30-inch (in) and 
36-in steel pipe piles for their new facilities with an estimated 52 
total days of impact pile driving. Pile driving will only occur within 
the Oregon Department of Fish and Wildlife (ODFW) approved in-water 
working window, however the proposed IHA will have a 1-year period of 
effectiveness
    A detailed description of the planned construction project is 
provided in the Federal Register notice for the proposed IHA (88 FR 
66393, September 27, 2023). Since that time, no changes have been made 
to the planned construction activities. Therefore, a detailed 
description is not provided here. Please refer to that Federal Register 
notice for the description of the specific activity.

Comments and Responses

    A notice of NMFS' proposal to issue an IHA to USCG was published in 
the Federal Register on September 17, 2023 (88 FR 66393). That notice 
described, in detail, USCG's activities, the marine mammal species that 
may be affected by the activities, and the anticipated effects on 
marine mammals. In that notice, we requested public input on the 
request for authorization described therein, our analyses, the proposed 
authorization, and any other aspect of the notice of proposed IHA, and 
requested that interested persons submit relevant information, 
suggestions, and comments. This proposed notice was available for a 30-
day public comment period. NMFS received no public comments.

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' U.S. Pacific and Alaska SARs. All values presented in table 1 are 
the most recent available at the time of publication 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
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/ MMPA status;   Stock abundance (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocoenidae (porpoises):
    Harbor Porpoise.................  Phocoena phocoena......  Northern Oregon/         -,-,N               21,487 (0.44, 15,123,         151      >=3.0
                                                                Washington Coast.                            2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    California Sea Lion.............  Zalophus californianus.  US.....................  -,-,N               257,606 (N/A, 233,515,     14,011       >321
                                                                                                             2014).
    Steller Sea Lion................  Eumetopias jubatus.....  Eastern................  -,-,N               43,201................      2,592        112
                                                                                                            (N/A, 43,201, 2017)...

[[Page 77987]]

 
Family Phocidae (earless seals):
    Harbor Seal.....................  Phoca vitulina.........  Oregon/Washington Coast  -,-,N               UNK...................        UND       10.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports/. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.

    As indicated above, all four species in table 2 temporally and 
spatially co-occur with the activity to the degree that take is 
reasonably likely to occur. While killer whales (Orcinus orca), 
humpback whales (Megaptera novaeangliae), and gray whales (Eschrichtius 
robustus) have been sighted off the Oregon coast, the USCG's project is 
located 23 kilometers (km) into the mouth of the Columbia River. 
Therefor 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 and in the USCG's 
application.
    A detailed description of the species likely to be affected by the 
USCG's construction project, including brief introductions to the 
species and relevant stocks as well as available information regarding 
population trends and threats, and information regarding local 
occurrence, were provided in the Federal Register notice for the 
proposed IHA (88 FR 66393, September 27, 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 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 ~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 USCG's construction activities 
have the potential to result in behavioral harassment of marine mammals 
in the vicinity of the project area. The notice of proposed IHA (88 FR 
66393, September 27, 2023) included a discussion of the effects of 
anthropogenic noise on marine mammals and the potential effects of 
underwater noise from the USCG's pile

[[Page 77988]]

driving activities on marine mammals and their habitat. That 
information and analysis is incorporated by reference into this notice 
and is not repeated here; please refer to the notice of the proposed 
IHA (88 FR 66393, September 27, 2023).

Estimated Take of Marine Mammals

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

Acoustic Thresholds

    NMFS recommends the use of acoustic thresholds that identify the 
received level of underwater sound above which exposed marine mammals 
would be reasonably expected to be behaviorally harassed (equated to 
Level B harassment) or to incur permanent threshold shift (PTS) of some 
degree (equated to Level A harassment).
    Level B Harassment--Though significantly driven by received level, 
the onset of behavioral disturbance from anthropogenic noise exposure 
is also informed to varying degrees by other factors related to the 
source or exposure context (e.g., frequency, predictability, duty 
cycle, duration of the exposure, signal-to-noise ratio, distance to the 
source), the environment (e.g., bathymetry, other noises in the area, 
predators in the area), and the receiving animals (hearing, motivation, 
experience, demography, life stage, depth) and can be difficult to 
predict (e.g., Southall et al., 2007, 2021, Ellison et al., 2012). 
Based on what the available science indicates and the practical need to 
use a threshold based on a metric that is both predictable and 
measurable for most activities, NMFS typically uses a generalized 
acoustic threshold based on received level to estimate the onset of 
behavioral harassment. NMFS generally predicts that marine mammals are 
likely to be behaviorally harassed in a manner considered to be Level B 
harassment when exposed to underwater anthropogenic noise above root-
mean-squared pressure received levels (RMS SPL) of 120 dB (referenced 
to 1 micropascal (re 1 [mu]Pa)) for continuous (e.g., vibratory pile 
driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa for non-
explosive impulsive (e.g., seismic airguns) or intermittent (e.g., 
scientific sonar) sources. Generally speaking, Level B harassment take 
estimates based on these behavioral harassment thresholds are expected 
to include any likely takes by 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.
    USCG's planned activity includes the use of impulsive (impact pile 
driving) sources, and therefore the RMS SPL threshold of 160 dB re 1 
[mu]Pa is 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). USCG's 
planned activity includes the use of impulsive (impact pile driving) 
sources.
    These thresholds are provided in the table below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS' 2018 Technical Guidance, which may be accessed at: 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 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.

[[Page 77989]]

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

Ensonified Area

    Underwater sound propagation modeling was completed by USCG using 
dBSea, a software developed by Marshall Day Acoustics for the modeling 
of underwater sound propagation in a variety of environments. The model 
was built by importing bathymetry data and placing noise sources in the 
environment. Each source can consist of equipment chosen from either 
the standard or the user-defined databases. Noise mitigation methods 
may also be included. The user has control over the seabed and water 
properties including sound speed profile, temperature, salinity, and 
current. Noise levels were calculated to the extent of the bathymetry 
area. To examine results in more detail, levels may be plotted in cross 
sections, or a detailed spectrum may be extracted at any point in the 
calculation area. Levels were calculated in third octave bands from 
12.5 (hertz) Hz to 20 kHz. Please refer to Acoustic Assessment included 
in USCG's application for additional details on the modeling principles 
and assumptions.
    The representative acoustic modeling scenarios were derived from 
descriptions of the expected construction activities through 
consultations between the USCG project design and engineering teams. 
The scenarios modeled were ones where potential underwater noise 
impacts of marine species were anticipated and included impact pile 
driving associated with pier installation. All modeling scenarios occur 
at a representative location. This location was selected so that the 
effects of sound propagation at the range of water column depths 
occurring within the project area could be evaluated.
    The USCG opted to perform their own acoustic modeling for the Level 
A and Level B harassment isopleths as they had site specific 
information to input into the model, which may assist in providing more 
accurate results than, for example, use of NMFS' User Spreadsheet tool, 
which is a relatively simple tool that cannot incorporate site-specific 
environmental information. The modeling used by USCG takes into account 
bathymetry, geo-acoustic properties of sub-bottom sediments, and sound 
speed profile. NMFS has reviewed USCG's modeling and determined that it 
is acceptable for use here.
    A summary of construction and operational scenarios included in the 
underwater acoustic modeling analysis is provided in the Acoustic 
Assessment and summarized in table 5 below. The pile diameters selected 
for the impact pile driving modeling scenarios were based on maximum 
project design considerations approximated by USCG. The Level A and 
Level B harassment isopleths for the planned activities are shown in 
table 4 and 5.

                               Table 4--Source Levels for Impact Pile Installation
----------------------------------------------------------------------------------------------------------------
           Pile size               Peak SPLs (dB)     RMS SPLs (dB)        SELss (dB)             Source
----------------------------------------------------------------------------------------------------------------
36-in pile.....................                208                190                180  Caltrans 2020.
30-in pile.....................                210                190                177  Caltrans 2020.
----------------------------------------------------------------------------------------------------------------


                    Table 5--Level A and Level B Harassment Isopleths for Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
                                                    Level A harassment zones (m)                    Level B
              Activity               ---------------------------------------------------------  harassment zone
                                         HF cetaceans     Phocid pinnipeds  Otariid pinnipeds         (m)
----------------------------------------------------------------------------------------------------------------
36-in pile..........................                287                197                  0                602
30-in pile..........................                213                130                  0                602
----------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide information about the occurrence of 
marine mammals, including density or other relevant information which 
will inform the take calculations and describe how the information 
provided is synthesized to produce a quantitative estimate of the take 
that is reasonably likely to occur and authorized. The USCG used marine 
mammal species densities from the Pacific Navy Marine Species Density 
Database to estimate take for marine mammals. This database 
incorporates

[[Page 77990]]

analyzed literature and research for marine mammal density estimates 
per season for regions throughout the U.S. and the USCG based their 
take estimates on regionally available population density estimates and 
site-specific knowledge. Although this database provides densities for 
all species present in the action area, the densities are based on 
offshore abundance and not directly relevant to occurrence within in 
the Columbia River. Following careful review of the analysis presented 
by the USCG in its application, including marine mammal occurrence 
data, NMFS has determined that different information inputs than those 
selected by the USCG represent the best available scientific 
information for marine mammal abundance in the action area. These 
selections are discussed in greater detail below.

Steller Sea Lion, California Sea Lion and Harbor Seal

    For Steller sea lions, California sea lions, and harbor seals, the 
numbers of individuals were referenced from Washington Department of 
Fish and Wildlife's (WDFW) surveys from 2000-2014 at the South Jetty 
for the months of in water work (November through February) and 
averaged to get an estimated daily count (table 6). While animals were 
surveyed at the prominent haul out site along the South Jetty, since 
the ETP site is close to the mouth of the river and the South Jetty, we 
assumed each of these estimates represents a good proxy for the total 
number of individuals that could be present in the project vicinity. We 
derived potential take estimates from the average abundance recorded 
over the specified period.

                                              Table 6--Pinniped Counts From the South Jetty From 2000-2014
                                                                       [WDFW 2014]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Steller sea lion   Steller sea lion    California sea     California sea      Harbor seal        Harbor seal
                                            (monthly)           (daily)         lion (monthly)      lion (daily)        (monthly)           (daily)
--------------------------------------------------------------------------------------------------------------------------------------------------------
November..............................               1663                 55               1214                 40                  0                  0
December..............................               1112                 36                725                 23                 57                  2
January...............................                249                  8                 10                0.3                  0                  0
February..............................                259                  9                 28                  1                  1               0.04
Average (all months)..................                821                 27                494                 16                 15                0.5
--------------------------------------------------------------------------------------------------------------------------------------------------------

    To calculate the total estimated takes, we multiplied the estimated 
days of activity by the associated average daily pinniped counts 
(monthly count/days of the month and averaged across all months) for 
each species (table 7).

                                  Table 7--Estimated Take of Steller Sea Lions, California Sea Lions, and Harbor Seals
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Steller sea                   California sea
                                              Days of       Steller sea        lion       California sea       lion         Harbor seal     Harbor seal
          Pile type and method               activity      lion average     calculated     lion average     calculated     average count  calculate take
                                                               count           take            count           take
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-in Steel Pile Impact Installation....              52              27           1,404              16             832             0.5              26
30-in Steel Pile Impact Installation....
--------------------------------------------------------------------------------------------------------------------------------------------------------

    There is some potential for take by Level A harassment of harbor 
seals due to the largest zone being approximately 200 m and because of 
the cryptic nature and assumed lower detectability of harbor seals at 
this distance. Based on the relative proportion of the area expected to 
be ensonified above the Level A harassment threshold for phocid 
pinnipeds from impact pile driving (approximately 0.36 square 
kilometers (km\2\)) to the area ensonified above the Level B harassment 
threshold (1.1 km\2\ for impact pile driving), we estimated that of the 
total number of harbor seals that may be located within the greater 
Level B harassment zone, approximately 33 percent would approach the 
pile driving activities closer and enter the smaller Level A harassment 
zone (197 m). Thus, we assume that 33 percent of the total estimated 
takes of harbor seals (26 individuals; see table 7) would be by Level A 
harassment. Therefore, we are proposing to authorize 9 takes of harbor 
seals by Level A harassment and 17 takes by Level B harassment (table 
8).
    The Level A harassment zone for otariid pinnipeds is 0 m. The USCG 
would be required to enforce a minimum shutdown zone of 10 m for these 
species. At that close range, the USCG would be able to detect 
California sea lions and Steller sea lions and implement the required 
shutdown measures before any sea lions could enter the Level A 
harassment zone. Therefore, no takes of California sea lions or Steller 
sea lions by Level A harassment are requested or authorized.

Harbor Porpoise

    Harbor porpoises are regularly observed in the coastal waters near 
the mouth of the Columbia River and are known to occur year-round, 
although this project occurs farther upstream in the Columbia River. 
Their nearshore abundance peaks with anchovy presence, which is 
generally June through October. However, there was one recorded 
sighting of a harbor porpoise in the project area east of the jetties 
in the September-November timeframe (OBIS-SEAMAP 2019). During 
monitoring for pile driving at the Columbia River Jetty System which is 
at the mouth of the Columbia River approximately 23 km from the USCG's 
planned action area, over the course of a 5 day monitoring period, 
observers detected five harbor porpoises (Grette Associates 2016). 
Additionally we reviewed monitoring reports from four recent projects 
in the nearby area (Army Corps of Engineers King Pile Markers and Sand 
Island Pile Dike Test Piles, and Phase 1 and 2 of the City of Astoria 
Bridge Replacement which can be found at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations). 
Only one project with

[[Page 77991]]

activities occurring over 15 days had eight sightings of harbor 
porpoise at Sand Island Dike.
    Given that, there is some potential for harbor porpoise to be 
present near the project area, and based on the previously mentioned 
monitoring reports sighting data, we calculated that harbor porpoise 
could enter the Level B harassment zone every other day of pile driving 
(or 0.5/day). To calculate the total estimated takes by Level B 
harassment, we multiplied the estimated days of activity by the 
associated daily harbor porpoise rate (table 8).
    There is also some potential for take by Level A harassment of 
harbor porpoise due to the largest zone being approximately 300 m and 
because of the cryptic nature and assumed lower detectability of harbor 
porpoise at this distance. The USCG anticipates that 12 harbor 
porpoises during impact driving could be taken by Level A harassment. 
Take by Level A harassment for harbor porpoise was calculated in the 
same way it was for harbor seals. In total, we are proposing to 
authorize take of 26 harbor porpoises (table 8).

                    Table 8--Take of Marine Mammals by Level A and Level B Harassment by Species, Stock and Percent of Take by Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                               Total
                  Species                               Stock              Take by Level   Take by Level    authorized         Stock        Percent of
                                                                           A harassment    B harassment        take          abundance         stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Porpoise...........................  Northern Oregon/Washington                12              14              26          21,487             0.1
                                             Coast.
California sea lion.......................  U.S.........................               0             832             832         257,606             0.3
Steller sea lion..........................  Eastern.....................               0           1,404           1,404          43,201             3.2
Harbor seal...............................  Oregon/Washington Coast.....               9              17              26          24,732             0.1
--------------------------------------------------------------------------------------------------------------------------------------------------------

Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses (latter not applicable for this action). 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. 
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.

Time Restrictions

    The USCG has proposed in its description of the project that pile 
driving would occur only during daylight hours (no sooner than 30 
minutes after sunrise through no later than 30 minutes before sunset), 
when visual monitoring of marine mammals can be conducted. In addition, 
ODFW requires all in-water construction be limited to the months of 
November through February to minimize impacts to ESA listed fish 
species.

Mitigation Measures

    USCG must follow mitigation measures as specified below:
     Ensure that construction supervisors and crews, the 
monitoring team, and relevant USCG staff are trained prior to the start 
of all pile driving activity, so that responsibilities, communication 
procedures, monitoring protocols, and operational procedures are 
clearly understood. New personnel joining during the project must be 
trained prior to commencing work;
     Employ Protected Species Observers (PSOs) and establish 
monitoring locations as described in the application and the IHA. USCG 
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, 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 activity 
will ensure that the entire shutdown zone, see table 9, is visible 
during pile driving activities. Should environmental conditions 
deteriorate such that marine mammals within the entire shutdown zone 
will not be visible (e.g., fog, heavy rain), pile driving and removal 
must be delayed until the PSO is confident marine mammals within the 
shutdown zone could be detected;
     Monitoring must take place from 30 minutes prior to 
initiation of pile driving activity (i.e., pre-clearance monitoring) 
through 30 minutes post-completion of pile driving activity;
     Pre-start clearance monitoring must be conducted during 
periods of visibility sufficient for the lead PSO to determine that the 
shutdown zones indicated in table 9 are clear of marine mammals. Pile 
driving may commence following 30 minutes of observation when the 
determination is made that the shutdown zones are clear of marine 
mammals;
     USCG 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; and
     If a marine mammal is observed entering or within the 
shutdown zones indicated in table 9, pile driving must

[[Page 77992]]

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.

Shutdown Zones

    USCG will establish shutdown zones for all pile driving activities. 
The purpose of a shutdown zone is generally to define an area within 
which shutdown of the activity would occur upon sighting of a marine 
mammal (or in anticipation of an animal entering the defined area). 
Shutdown zones would be based upon the Level A harassment zone for each 
pile size/type 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 would also serve to 
protect marine mammals from physical interactions with project vessels 
during pile driving and other construction activities, such as barge 
positioning or drilling. If an activity is delayed or halted due to the 
presence of a marine mammal, the activity may not commence or resume 
until either the animal has voluntarily exited and been visually 
confirmed beyond the shutdown zone indicated in table 9 or 15 minutes 
have passed without re-detection of the animal. Construction activities 
must be halted upon observation of a species for which incidental take 
is not authorized or a species for which incidental take has been 
authorized but the authorized number of takes has been met entering or 
within the harassment zone.
    All marine mammals will be monitored in the Level B harassment 
zones and throughout the area as far as visual monitoring can take 
place. If a marine mammal enters the Level B harassment zone, in-water 
activities will continue and the animal's presence within the estimated 
harassment zone will be documented.
    USCG will also establish shutdown zones for all marine mammals for 
which take has not been authorized or for which incidental take has 
been authorized but the authorized number of takes has been met. These 
zones are equivalent to the Level B harassment zones for each activity. 
If a marine mammal species not covered under this IHA enters the 
shutdown zone, all in-water activities will cease until the animal 
leaves the zone or has not been observed for at least 15 minutes, and 
NMFS will be notified about species and precautions taken. Pile driving 
will proceed if the non-IHA species is observed to leave the Level B 
harassment zone or if 15 minutes have passed since the last 
observation.
    If shutdown and/or clearance procedures would result in an imminent 
safety concern, as determined by USCG 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 Zones and Monitoring Zones
----------------------------------------------------------------------------------------------------------------
                                                     Minimum shutdown zone (m)
              Activity               ---------------------------------------------------------  Harassment zone
                                         HF cetaceans          Phocid            Otariid              (m)
----------------------------------------------------------------------------------------------------------------
36-in Impact Installation...........                300                 50                 10                610
30-in Impact Installation...........                220                 50                 10                610
----------------------------------------------------------------------------------------------------------------

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 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.
    Based on our evaluation of USCG's planned measures, as well as 
other measures considered by NMFS, NMFS has determined that the 
mitigation measures provide the means effecting the least practicable 
impact on the affected species or stocks and their habitat, paying 
particular attention to 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;

[[Page 77993]]

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

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
conditions in this section and the IHA. Marine mammal monitoring during 
pile driving activities will be conducted by PSOs meeting the following 
requirements:
     PSOs must be independent of the activity contractor (for 
example, employed by a subcontractor) and have no other assigned tasks 
during monitoring periods;
     At least one PSO will have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
     Other PSOs may substitute education (degree in biological 
science or related field) or training for experience; and
     Where a team of three or more PSOs is required, a lead 
observer or monitoring coordinator will be designated. The lead 
observer will be required to have prior experience working as a marine 
mammal observer during construction.
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
     USCG must employ three PSOs during all pile driving 
activities depending on the size of the monitoring and shutdown zones. 
A minimum of one PSO must be assigned to monitor waters surrounding the 
active pile driving location.
     USCG must establish the following monitoring locations 
with the best views of monitoring zones as described below, in the IHA, 
and USCG's application.
     PSOs would be deployed in strategic locations around the 
harassment zone at all times during in-water pile driving. PSOs will be 
positioned at locations that provide full views of the impact hammering 
monitoring zones and the shutdown zones. PSOs will be stationed on the 
staging barges, on shore at the project site, and at the entrance to 
the commercial dock area at ETP. All PSOs will have access to high-
quality binoculars, range finders to monitor distances, and a compass 
to record bearing to animals as well as radios or cells phones for 
maintaining contact with work crews.
    Monitoring will be conducted 30 minutes before, during, and 30 
minutes after all in water construction activities. In addition, PSOs 
will record all incidents of marine mammal occurrence, regardless of 
distance from activity, and will document any behavioral reactions in 
concert with distance from piles being driven or removed. Pile driving 
activities include the time to install or remove a single pile or 
series of piles, as long as the time elapsed between uses of the pile 
driving equipment is no more than 30 minutes.
    USCG shall conduct briefings between construction supervisors and 
crews, PSOs, USCG 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, or 60 days prior to a requested date of issuance from any 
future IHAs for projects at the same location, whichever comes first. 
The report will include an overall description of work completed, a 
narrative regarding marine mammal sightings, and associated PSO data 
sheets. Specifically, the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring;
     Construction activities occurring during each daily 
observation period, including the number and type of piles driven or 
removed and by what method (i.e., impact) and the total number of 
strikes for each pile;
     PSO locations during marine mammal monitoring;
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
    Upon observation of a marine mammal, the following information:
     Name of PSO who sighted the animal(s) and PSO location and 
activity at the time of sighting;
     Time of sighting;
     Identification of the animal(s) (e.g., genus/species, 
lowest possible taxonomic level, or unidentifiable), PSO confidence in 
identification, and the composition of the group if there is a mix of 
species;
     Distance and bearing of each marine mammal observed 
relative to the pile being driven for each sightings (if pile driving 
was occurring at time of sighting);
     Estimated number of animals (min/max/best estimate);
     Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, sex class, etc.);
     Animal's closest point of approach and estimated time 
spent within the harassment zone;
     Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted from the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones and shutdown zones; by species;
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensured, and resulting changes in behavior of the 
animal(s), if any; and
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.

[[Page 77994]]

Reporting Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the USCG must immediately 
cease the specified activities and report the incident to the Office of 
Protected Resources (OPR) ([email protected]), NMFS and 
to the West Coast Regional Stranding Coordinator as soon as feasible. 
If the death or injury was clearly caused by the specified activity, 
USCG must immediately cease the specified activities until NMFS is able 
to review the circumstances of the incident and determine what, if any, 
additional measures are appropriate to ensure compliance with the terms 
of the IHA. The USCG must not resume their activities until notified by 
NMFS. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any impacts or responses (e.g., intensity, duration), 
the context of any impacts or responses (e.g., critical reproductive 
time or location, foraging impacts affecting energetics), as well as 
effects on habitat, and the likely effectiveness of the mitigation. We 
also assess the number, intensity, and context of estimated takes by 
evaluating this information relative to population status. Consistent 
with the 1989 preamble for NMFS' implementing regulations (54 FR 40338; 
September 29, 1989), the impacts from other past and ongoing 
anthropogenic activities are incorporated into this analysis via their 
impacts on the baseline (e.g., as reflected in the regulatory status of 
the species, population size and growth rate where known, ongoing 
sources of human-caused mortality, or ambient noise levels).
    To avoid repetition, our analysis applies to all species listed in 
table 1 for which take could occur, given that NMFS expects the 
anticipated effects of the planned pile driving on different marine 
mammal stocks to be similar in nature. Where there are meaningful 
differences between species or stocks, or groups of species, in 
anticipated individual responses to activities, impact of expected take 
on the population due to differences in population status, or impacts 
on habitat, NMFS has identified species-specific factors to inform the 
analysis.
    Pile driving activities associated with the USCG construction 
project have the potential to disturb or displace marine mammals. 
Specifically, the project activities may result in take, in the form of 
Level A and Level B harassment, from underwater sounds generated from 
pile driving. Potential takes could occur if individuals are present in 
the ensonified zone when these activities are underway.
    No serious injury or mortality would be expected, even in the 
absence of required mitigation measures, given the nature of the 
activities. Further, limited take by Level A harassment is authorized 
for two species, but the potential for harassment would be minimized 
through the construction method and the implementation of the planned 
mitigation measures (see Mitigation section).
    Take by Level A harassment is authorized for harbor seals and 
harbor porpoise to account for the possibility that an animal could 
enter a Level A harassment zone prior to detection, and remain within 
that zone for a duration long enough to incur PTS before being observed 
and the USCG shutting down pile driving activity. 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 (i.e. the low-frequency region below 2 kHz), not severe 
hearing impairment or impairment within the ranges of greatest hearing 
sensitivity. Animals would need to be exposed to higher levels and/or 
longer duration than are expected to occur here in order to incur any 
more than a small degree of PTS.
    Further, the amount of authorized take by Level A harassment is 
very low for both marine mammal 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.
    Additionally, some subset of the individuals that are behaviorally 
harassed could also simultaneously incur some small degree of TTS for a 
short duration of time. However, since the hearing sensitivity of 
individuals that incur TTS is expected to recover completely within 
minutes to hours, it is unlikely that the brief hearing impairment 
would affect the individual's long-term ability to forage and 
communicate with conspecifics, and would therefore not likely impact 
reproduction or survival of any individual marine mammal, let alone 
adversely affect rates of recruitment or survival of the species or 
stock.
    The Level A harassment zones identified in table 5 are based upon 
an animal's exposure to pile driving of up to three steel piles per 
day. Given the short duration to impact drive 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 in the area. If an 
animal was exposed to accumulated sound energy, the resulting PTS would 
likely be small (e.g., PTS onset) at lower frequencies where pile 
driving energy is concentrated, and unlikely to result in impacts to 
individual fitness, reproduction, or survival.
    The nature of the pile driving project precludes the likelihood of 
serious injury or mortality. For all species and stocks, take would 
occur within a limited, confined area (adjacent to the project site) of 
the stock's range. Level A and Level B harassment will be reduced to 
the level of least practicable adverse impact through use of mitigation 
measures described herein. Further, the amount of take authorized is 
small when compared to stock abundance.

[[Page 77995]]

    Behavioral responses of marine mammals to pile driving in the 
Columbia River 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 would occur for only a portion of the project's 
duration, any harassment occurring would be temporary. Additionally, 
many of the species present in region would only be present temporarily 
based on seasonal patterns or during transit between other habitats. 
These temporarily present species would be exposed to even smaller 
periods of noise-generating activity, further decreasing the impacts.
    For all species, there are no known BIA near the project area that 
would be impacted by USCG's planned activities. While California sea 
lions and harbor seals are the species most likely to occur within the 
immediate project area the nearest haul out for both species is 
approximately 3 miles (4.8 km) away. There are three known haul out 
sites for both species near the project area including Tongue Point 
Sands, Taylor Sands, and Green Island/Sanborn Slough, the closest being 
Tongue Point Sands 3 miles (4.8 km) from the project area. 
Additionally, there is a Steller sea lion haul out in the Columbia 
River; it is approximately 15 miles (24.1 km) away from the project 
site at the south jetty off the western shoreline of Fort Stevens State 
Park. None of these haul outs are in the immediate project vicinity.
    In addition, it is unlikely that minor noise effects in a small, 
localized area of habitat would have any effect on each stock's 
continued survival. 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;
     Authorized Level A harassment would be very small amounts 
and of low degree;
     For all species, the mouth of the Columbia River is a very 
small and peripheral part of their range;
     The intensity of anticipated takes by Level B harassment 
is relatively low for all stocks. Level B harassment would be primarily 
in the form of behavioral disturbance, resulting in avoidance of the 
project areas around where impact 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;
     The lack of anticipated significant or long-term negative 
effects to marine mammal habitat; and
     USCG would implement mitigation measures including soft 
starts and shutdown zones to minimize the numbers of marine mammals 
exposed to injurious levels of sound, and to ensure that take by Level 
A harassment is, at most, a small degree of PTS.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the planned 
activities 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. For all species, the 
authorized take is below one third of the population for all marine 
mammal stocks (Table 8).
    Based on the analysis contained herein of the planned activity 
(including the mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS finds that small numbers of marine mammals 
would be taken relative to the population size of the affected species 
or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA; 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure ESA compliance for the issuance of IHAs, 
NMFS consults internally whenever we propose to authorize take for 
endangered or threatened species.
    No incidental take of ESA-listed species is authorized or expected 
to result from this activity. Therefore, NMFS has determined that 
formal consultation under section 7 of the ESA is not required for this 
action.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our action (i.e., the issuance of an IHA) with respect 
to potential impacts on the human environment. This action is 
consistent with categories of activities identified in Categorical 
Exclusion B4 (IHAs with no anticipated serious injury or mortality) of 
the Companion Manual for NAO 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the

[[Page 77996]]

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 the 
IHA qualifies to be categorically excluded from further NEPA review.

Authorization

    As a result of these determinations, NMFS issued an IHA to USCG for 
conducting impact pile driving associated with the ETP project in 
Astoria, Oregon, provided the previously mentioned mitigation, 
monitoring, and reporting requirements are incorporated. The final IHA 
can be found at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-united-states-coast-guards-construction-astoria-oregon.

    Dated: November 7, 2023.
Shannon Bettridge,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2023-24980 Filed 11-13-23; 8:45 am]
BILLING CODE 3510-22-P