[Federal Register Volume 87, Number 161 (Monday, August 22, 2022)]
[Notices]
[Pages 51346-51359]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-17976]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XC221]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Sand Island Pile Dikes Repairs in 
the Columbia River

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

ACTION: Notice; issuance of an incidental harassment authorization 
(IHA).

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued two consecutive IHAs to the U.S. Army Corps of 
Engineers (Corps) to incidentally harass marine mammals during in-water 
construction activities associated with the Sand Island Pile Dikes 
Repairs Project in the Columbia River. There are no changes from the 
proposed authorizations in these final authorizations.

DATES: These authorizations are effective from August 1, 2023 through 
July 31, 2024 and August 1, 2024 through July 31, 2025.

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

[[Page 51347]]

activities. In case of problems accessing these documents, please call 
the contact listed above.

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 March 4, 2022, NMFS received a request from the Corps for two 
IHAs to take marine mammals incidental to the Sand Island Pile Dikes 
Repairs Project in the Columbia River over the course of two years. The 
application was deemed adequate and complete on June 9, 2022. The 
Corps' request is for take of seven species of marine mammals by Level 
B harassment and, for a subset of these species (harbor seal (Phoca 
vitulina) and harbor porpoise (Phocoena phocoena)), Level A harassment. 
Neither the Corps nor NMFS expect serious injury or mortality to result 
from these activities and, therefore, IHAs are appropriate.
    There are no changes from the proposed IHA to the final IHA.

Description of Proposed Activity

Overview

    The Sand Island pile dikes are part of the Columbia River pile dike 
system and are comprised of four pile dikes, which are named according 
to river mile (RM) location, at RMs 4.01, 4.47, 5.15, and 6.37. The 
purpose of the Sand Island Pile Dikes Repairs project is to perform 
needed repairs. The existing timber pile dikes at Sand Island consist 
of three rows of vertical timber pilings between 12 and 20 inches (in) 
in diameter with two rows of horizontal spreaders, which provide 
structural stability of the vertical timber pilings. A cluster of piles 
with one or more taller piles, called an outer dolphin with king piles, 
is used to anchor and mark the end for navigational safety. There is 
rock apron at the base of the vertical piles and at the shore 
connection to protect against scour. The existing pile dikes have 
deteriorated greatly due to lack of maintenance.
    The major project elements planned to be conducted under these IHAs 
include work at pile dikes 6.37 and 5.15. The Corps plans to remove 
existing timber piles, drive new steel pipe piles and place rock for 
multiple purposes including scour protection at the base of the new 
piles, enhanced enrockment segments, shore connections, and revetment 
along the western portion of the shoreline at East Sand Island. In 
addition, the Corps plans to construct a temporary material off-loading 
facility (MOF) to support the planned construction work. All piles 
installed to construct the MOF will be subsequently removed in the same 
year.

                                                          Table 1--Year 1 Proposed Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                Pile size and                                         Maximum piles      Duration or     Estimated days  Estimated month
       Project element               type            Method        Number of piles       per day      strikes per pile       of work         of work
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pile dike 6.37...............  24-in steel      Vibratory        171 \a\...........          14 \b\  15 minutes........              56  August-Septembe
                                pipe.            install.                                                                                 r.
Pile dike 6.37...............  24-in steel      Impact install.  ..................    225 strikes.
                                pipe.
MOF..........................  24-in steel      Vibratory        Up to 24 \c\......               5  30 minutes........               5  October.
                                pipe.            install.
MOF..........................  24-in steel      Vibratory        ..................              20  5 minutes.........               1  October.
                                pipe.            removal.
MOF..........................  24-in steel      Vibratory        Up to 100 \c\.....              25  10 minutes........               4  October.
                                sheet.           install.
MOF..........................  24-in steel      Vibratory        ..................              50  3 minutes.........               1  October.
                                sheet.           removal.
                              --------------------------------------------------------------------------------------------------------------------------
    Total days of work.......  ...............  ...............  ..................  ..............  ..................              67  ...............
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ A total of 244 steel pipe piles will be installed at PD 6.37 over the two years, with approximately 70 percent installed in year 1 and the remaining
  30 percent installed in year 2. These same 171 piles will be installed using both vibratory and impact hammers.
\b\ The Corps estimates an average of 5 piles will be installed per day but could be up to 14 per day.
\c\ The same MOF piles will be installed and subsequently removed.


                                                          Table 2--Year 2 Proposed Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                Pile size and                                         Maximum piles      Duration or     Estimated days  Estimated month
       Project element               type            Method        Number of piles       per day      strikes per pile       of work         of work
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pile dike 6.37...............  24-in steel      Vibratory        73 \a\............          14 \b\  15 min............              24  August.
                                pipe.            install.
                               Impact install.  ...............  ..................    225 strikes.
Pile dike 5.15...............  24-in steel      Vibratory        150...............              14  15 min............              71  August-November
                                pipe.            install.                                                                                 .
                               Impact install.  ...............  ..................    225 strikes.
                              --------------------------------------------------------------------------------------------------------------------------
    Total days of work.......  ...............  ...............  ..................  ..............  ..................              95  ...............
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ These same 73 piles will be installed using both vibratory and impact hammers.
\b\ The Corps estimates an average of 5 piles will be installed per day but could be up to 14 per day.


[[Page 51348]]

    A detailed description of the planned activities is provided in the 
Federal Register notice of the proposed IHAs (87 FR 39481; July 1, 
2022). 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 descriptions of the 
specific activities. Mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Mitigation and 
Monitoring and Reporting sections).

Comments and Responses

    A notice of NMFS' proposal to issue the IHAs to the Corps was 
published in the Federal Register on July 1, 2022 (87 FR 39481). That 
notice described, in detail, the Corps' 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. No public comments were received on the 
proposed notice.

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, incorporated here by reference, instead of 
reprinting the information. Additional information regarding population 
trends and threats may be found in NMFS' Stock Assessment Reports 
(SARs; 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 3 lists all species or stocks for which take is expected and 
proposed to be authorized for this activity, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and Endangered Species Act (ESA) and potential biological 
removal (PBR), where known. PBR is defined by the MMPA as the maximum 
number of animals, not including natural mortalities, that may be 
removed from a marine mammal stock while allowing that stock to reach 
or maintain its optimum sustainable population (as described in NMFS' 
SARs). While no serious injury or mortality is expected to occur, 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 3 are 
the most recent available at the time of publication and are available 
in the 2020 SARs (Carretta et al., 2021; Muto et al., 2022) and draft 
2021 SARs (available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports).

                          Table 3--Species Likely Impacted by the Specified Activities
----------------------------------------------------------------------------------------------------------------
                                                                             Stock abundance
                                                                  ESA/MMPA      (CV, Nmin,
         Common name           Scientific name       Stock         status;     most recent       PBR    Annual M/
                                                                  strategic     abundance                SI \3\
                                                                  (Y/N) \1\    survey) \2\
----------------------------------------------------------------------------------------------------------------
                      Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
----------------------------------------------------------------------------------------------------------------
Family Balaenopteridae
 (rorquals):
    Humpback whale...........  Megaptera        California/      E, D, Y     4,973 (0.05,         28.7   >= 48.6
                                novaeangliae.    Oregon/                      4,776, 2018).
                                                 Washington.
----------------------------------------------------------------------------------------------------------------
                        Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
----------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Killer Whale.............  Orcinus orca...  West Coast       -, -, N     349 \4\ (N/A,         3.5       0.4
                                                 Transient.                   349, 2018).
----------------------------------------------------------------------------------------------------------------
Family Phocoenidae
 (porpoises):
    Harbor Porpoise..........  Phocoena         Northern Oregon/ -, -, N     21,487 (0.44,         151     >=3.0
                                phocoena.        Washington                   15,123, 2011).
                                                 Coast.
----------------------------------------------------------------------------------------------------------------
                                     Order Carnivora--Superfamily Pinnipedia
----------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals
 and sea lions):
    California Sea Lion......  Zalophus         U.S............  -, -, N     257,606 (N/        14,011      >320
                                californianus.                                A,233,515,
                                                                              2014).
    Steller Sea Lion.........  Eumetopias       Eastern........  -, -, N     43,201 \5\ (see     2,592       112
                                jubatus.                                      SAR, 43,201,
                                                                              2017).
Family Phocidae (earless
 seals):
    Harbor Seal..............  Phoca vitulina.  Oregon/          -, -, N     24,732 \6\            UND      10.6
                                                 Washington                   (UNK, UNK,
                                                 Coast.                       1999).
    Northern Elephant Seal...  Mirounga         California       -, -, N     187,386 (N/A,       5,122      13.7
                                angustirostris.  Breeding.                    85,369, 2013).
----------------------------------------------------------------------------------------------------------------
\1\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species
  is not listed under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one
  for which the level of direct human-caused mortality exceeds PBR or which is determined to be declining and
  likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is
  automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. 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 mortality/serious injury (M/SI)
  often cannot be determined precisely and is in some cases presented as a minimum value or range.
\4\ Based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance
  estimates of these stocks are conducted infrequently.

[[Page 51349]]

 
\5\ Best estimate of pup and non-pup counts, which have not been corrected to account for animals at sea during
  abundance surveys.
\6\ The abundance estimate for this stock is greater than eight years old and is therefore not considered
  current. PBR is considered undetermined for this stock, as there is no current minimum abundance estimate for
  use in calculation. We nevertheless present the most recent abundance estimates, as these represent the best
  available information for use in this document.

    As indicated above, all seven species (with seven managed stocks) 
in Table 3 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 proposed project area are included in Table 4 
of the IHA application. While gray whales (Eschrichtius robustus) and 
killer whales from the Southern Resident Distinct Population Segment 
(DPS) and stock have been reported near the mouth of the Columbia 
River, 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.
    Gray whales have not been documented near the proposed project area 
although anecdotal evidence indicates they have been seen at the mouth 
of the Columbia River. However, they are not a common visitor as they 
mostly remain in the vicinity of the offshore shelf-break (Griffith 
2015). They migrate along the Oregon coast in three discernible phases 
from early December through May (Herzing and Mate 1984). Therefore, 
they are unlikely to occur near the project area between August and 
November. Monitoring reports from recent IHAs issued to the Corps for 
similar construction work on the Columbia River Jetty System (e.g., 82 
FR 15046; March 23, 2017) reported no observations of gray whales. 
Given the size of gray whales, they could be readily identifiable at a 
considerable distance. If a gray whale were to approach the established 
Level B harassment isopleths, shutdown would be initiated to avoid 
take. The Corps would employ at least one vessel-based protected 
species observer (PSO) who would be able to adequately monitor these 
zones. Therefore, NMFS does expect take of gray whales to occur and no 
take is anticipated or authorized.
    Historically, killer whales were regular visitors in the vicinity 
of the estuary. However, they are much less common presently and are 
rarely seen in the interior of the Columbia River Jetty system (Wilson 
2015). Southern Resident killer whales have been documented near the 
mouth of the Columbia River but these observations have most commonly 
been during the late-winter to early-spring months (NMFS 2021), outside 
of the proposed construction window for these projects. Monitoring 
reports from recent IHAs issued to the Corps for similar construction 
work on the Columbia River Jetty System (e.g., 82 FR 15046; March 23, 
2017) reported no observations of killer whales. While it is possible 
that killer whales from the West Coast Transient stock may enter the 
project area (see Estimated Take section), it is unlikely that take of 
Southern Resident killer whales would occur, and no take is anticipated 
or authorized.
    A detailed description of the species likely to be affected by the 
Corps' Sand Island Pile Dikes Repairs Project, including brief 
introductions to the species and relevant stocks as well as information 
regarding population trends and threats, and information regarding 
local occurrence were provided in the Federal Register notice for the 
proposed IHA (87 FR 39481; July 1, 2022); 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 
the Federal Register notice for these descriptions. Please also refer 
to NMFS's website (https://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 4.

           Table 4--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
                                                    Generalized hearing
                  Hearing group                           range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)....  7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed   150 Hz to 160 kHz.
 whales, beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises,    275 Hz to 160 kHz.
 Kogia, river dolphins, Cephalorhynchid,
 Lagenorhynchus cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals).  50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions    60 Hz to 39 kHz.
 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,

[[Page 51350]]

please see NMFS (2018) for a review of available information.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from the City's construction 
activities have the potential to result in Level A and Level B 
harassment of marine mammals in the vicinity of the project area. The 
notice of proposed IHAs (87 FR 39481; July 1, 2022) included a 
discussion of the effects of anthropogenic noise on marine mammals and 
the potential effects of underwater noise from the City's construction 
activities on marine mammals and their habitat. That information and 
analysis is incorporated by reference into the final determinations for 
the IHAs and is not repeated here; please refer to the notice of 
proposed IHAs (87 FR 39481; July 1, 2022).
    The Estimated Take section later in this document includes a 
quantitative analysis of the number of individuals that are expected to 
be taken by this activity. The Negligible Impact Analysis and 
Determination section considers the content of this section, the 
Estimated Take section, and the Mitigation section, to draw conclusions 
regarding the likely impacts of these activities on the reproductive 
success or survivorship of individuals and whether those impacts are 
reasonably expected to, or reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers,'' and the negligible impact 
determinations.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance, which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes are primarily by Level B harassment (in the form 
of behavioral disturbance and temporary threshold shift (TTS)), as use 
of the acoustic sources (i.e., vibratory or impact pile driving and 
removal) have the potential to result in disruption of behavioral 
patterns and cause a temporary loss in hearing sensitivity for 
individual marine mammals. There is also some potential for auditory 
injury (Level A harassment) to result for porpoises and harbor seals 
because predicted auditory injury zones are larger. The required 
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 
authorized 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 proposed 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.
    The Corps' planned activities include the use of continuous 
(vibratory hammer) and impulsive (impact hammer) 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). The Corps' 
activities include the use of impulsive (impact hammer) and non-
impulsive (vibratory hammer) 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: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

[[Page 51351]]



                     Table 5--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 [mu]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.

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 proposed project. 
Marine mammals are expected to be affected by sound generated by the 
primary components of the project (i.e., impact and vibratory pile 
driving).
    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 
the Corps plans to use (Table 6).

                                             Table 6--Source Levels
----------------------------------------------------------------------------------------------------------------
                                                 Source Level (dB re 1 [mu]Pa)
      Pile type and method       ------------------------------------------------------------      Reference
                                         Peak                 RMS                 SEL
----------------------------------------------------------------------------------------------------------------
24-in steel pipe impact           203 dB............  190 dB............  177 dB............  CalTrans (2015).
 installation.
24-in steel pipe pile vibratory   Not available.....  161 dB............  Not available.....  U.S. Navy (2015).
 installation/removal.
24-in steel sheet pile vibratory  175 dB............  160 dB............  160 dB............  CalTrans (2015).
 installation/removal.
----------------------------------------------------------------------------------------------------------------

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 the Corps' planned activities in the absence of specific 
modelling. The Level B harassment zones for the Corps' planned 
activities are shown in Table 7.

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, and the resulting 
isopleths are reported below in Table 7. Due to the bathymetry and 
geography of the project areas, sound may not reach the full distance 
of the harassment isopleths in all directions.

[[Page 51352]]



                            Table 7--Level A Harassment and Level B Harassment Zones
----------------------------------------------------------------------------------------------------------------
                                                      Level A harassment zone (m)
                                     ------------------------------------------------------------     Level B
        Pile type and method              LF          MF          HF        Phocid      Otariid     harassment
                                       cetacean    cetacean    cetacean    pinniped    pinniped      zone  (m)
----------------------------------------------------------------------------------------------------------------
24-in Steel Pile Impact Installation       430.0        15.3       512.2       230.1        16.8           1,000
24-in Steel Pile Vibratory                   7.9         0.7        11.7         4.8         0.3           5,412
 Installation.......................
Steel Sheet Pile Vibratory                  36.8         3.3        54.4        22.4         1.6           4,642
 Installation.......................
Steel Sheet Pile Vibratory Removal..         9.6         0.9        14.2         5.8         0.4           4,642
----------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that informs the 
authorized take incidental to the Corps' pile driving activities. 
Unless otherwise specified, the term ``pile driving'' in this section, 
and all following sections, may refer to either pile installation or 
removal. Unless otherwise specified, the occurrence information 
described below is used to estimate take for both the Year 1 and Year 2 
IHAs. NMFS has carefully reviewed the Corps' analysis and concludes 
that it represents an appropriate and accurate method for estimating 
incidental take caused by the Corps' activities.
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 the Washington Department 
of Fish and Wildlife's (WDFW's) surveys from 2000-2014 at the South 
Jetty for the months of in water work (August through October) and 
averaged to get an estimated daily count (Table 8). While animals were 
surveyed at the prominent haul out site along the South Jetty, since 
the Sand Island pile dikes are very close to the mouth of the river and 
the South Jetty, the Corps assumed each of these estimates represent 
the total number of individuals present in the project vicinity. In 
instances where planned activities will occur over a span of two or 
more months, the Corps derived potential take estimates from the 
average abundance recorded over the specified period. For harbor seals, 
where abundance was only estimated in July, the Corps used that 
estimate for all projections.

                          Table 8--Pinniped Counts From the South Jetty From 2000-2014
                                                  [WDFW 2014 ]
----------------------------------------------------------------------------------------------------------------
                                                                    Steller sea   California sea
                                                                       lion            lion         Harbor seal
----------------------------------------------------------------------------------------------------------------
August..........................................................             324             115              57
Average August-September........................................             267             182              57
September.......................................................             209             249              57
October.........................................................             384             508              57
Average (all months)............................................             306             291              57
----------------------------------------------------------------------------------------------------------------

    To calculate the total estimated takes by Level B harassment, the 
Corps multiplied the estimated days of activity within each month (or 
total across months) by the associated monthly (or average across 
months) count of each species (Table 9).

                                           Table 9--Estimated Take of Steller Sea Lions, California Sea Lions, and Harbor Seals by Level B Harassment
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                    Steller sea
                                                                                   Days of pile     Steller sea        lion       California sea  California sea    Harbor seal     Harbor seal
                Project element                             Month(s)                driving in     lion average     calculated     lion average   lion calculate   average count    calculated
                                                                                     month(s)          count           take            count           take                            take
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Year 1
    Pile Dike 6.37............................  August-September................              56             267          14,952             182          10,192              57           3,192
    MOF.......................................  October.........................              11             384           4,224             508           5,588              57             627
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
        Total takes by Level B harassment:......................................................................          19,176          Total:          15,780          Total:           3,819
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Year 2
    Pile Dike 6.37............................  August..........................              24             324           7,776             115           2,760              57           1,368
    Pile Dike 5.15............................  August through October..........              71             306          21,726             291          20,661              57           4,047
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
        Total takes by Level B harassment:......................................................................          29,502          Total:          23,421          Total:           5,415
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    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 of 24-in steel pipe piles (approximately 0.23 
square kilometers (km\2\)) to the area ensonified above the Level B 
harassment threshold (up to 94 km\2\ for vibratory installation of 24-
in steel pipe piles), the Corps estimated that of the total number of 
harbor seals that may be located within the greater Level B harassment 
zone, no more than 1 percent would approach the pile driving activities 
closer and enter the smaller Level A harassment zone (231 m). Thus, the 
Corps assumes that one percent of the total estimated takes of

[[Page 51353]]

harbor seals (3,819 individuals in Year 1 and 5,415 individuals in Year 
2; see Table 9) would be by Level A harassment. Therefore, the Corps 
has requested, and NMFS has authorized, 38 takes of harbor seals by 
Level A harassment and 3,781 takes by Level B harassment in Year 1 and 
54 takes of harbor seals by Level A harassment and 5,361 takes by Level 
B harassment in Year 2 (Table 10).
    The largest Level A harassment zone for otariid pinnipeds is 16.8 
m. The Corps is required to enforce a minimum shutdown zone of 25 m for 
these species. At that close range, the Corps will 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.
Humpback Whale
    Humpback whales have been observed in the immediate vicinity of the 
project area in recent years. Humpbacks have been arriving in the lower 
Columbia estuary as early as mid-June and have been observed as late as 
mid-November with a peak of abundance coinciding with the peak 
abundance of forage fish in mid-summer. No surveys were located for the 
project area, but it is assumed that they could be present during pile 
driving activities. Given the higher observed abundances in summer, the 
Corps assumes up to two individuals per month could enter the Level B 
harassment zone during pile driving activities each year, for a total 
of 6 takes of humpback whales by Level B harassment in each year (Table 
10).
    The largest Level A harassment zone for low-frequency cetaceans for 
any pile type or method is 430 m. During impact pile driving, the Corps 
is required to implement a shutdown zone equivalent to the Level A 
harassment zone for low-frequency cetaceans. Given the visibility of 
humpback whales, the Corps will be able to detect humpback whales and 
shut down pile driving before any humpbacks could enter the Level A 
harassment zone. Therefore, no take of humpback whales by Level A 
harassment is requested or authorized.
Transient Killer Whale
    Killer whales were not detected in fall and winter aerial surveys 
off the Oregon coast documented in Adams et al. (2014). Aerial seabird 
marine mammal surveys observed zero killer whales in January 2011, zero 
in February 2012, and 10 in September 2012 within an approximately 
1,500 km\2\ range near the MCR (Adams 2014). While a rare occurrence, a 
pod of transient killer whales were detected near the Astoria Bridge in 
May of 2018 (Frankowicz 2018). There have been no confirmed sightings 
of southern resident killer whales entering the project area. The Corps 
estimates that no more than two transient killer whales per year could 
be near the mouth of the Columbia River during proposed work and taken 
by Level B harassment (Table 10).
    The largest Level A harassment zone for mid-frequency cetaceans for 
any pile type or method is 15.3 m. The Corps is required to implement a 
minimum 25 m shutdown zone for mid-frequency cetaceans. Given the 
visibility of killer whales, at that close range, the Corps will be 
able to detect transient killer whales and shut down pile driving 
before any killer whales could enter the Level A harassment zone. 
Therefore, no take of transient killer whales by Level A harassment is 
requested or authorized.
Harbor Porpoise
    Harbor porpoises are regularly observed in the oceanward waters 
adjacent to the project area and are known to occur year-round. Their 
nearshore abundance peaks with anchovy presence, which is generally 
June through October. There was one recorded sighting of a harbor 
porpoise in the project area east of the jetties in the Sept-Nov 
timeframe (OBIS-SEAMAP 2019). Therefore, it is feasible that animals 
could be present during pile driving activities. During monitoring for 
pile driving at the Columbia River Jetty System, over the course of a 
5-day monitoring period, observers detected five harbor porpoises 
(Grette Associates 2016). Given the potential for harbor porpoise to 
travel in pairs, the Corps estimates that one pair of harbor porpoises 
per day may enter the Level B harassment zone per day of pile driving 
(67 days in Year 1 and 95 days in Year 2) for a total of 134 harbor 
porpoises taken in Year 1 and 190 taken in Year 2.
    For impact installation of 24-in steel pipe piles, the Level A 
harassment zone for high-frequency cetaceans is 512 m. Although the 
Corps is required to implement a shutdown zone of 515 m during this 
activity (see Mitigation), due to the cryptic nature and lower 
detectability of harbor porpoises at large distances, the Corps 
anticipates that up to 16 of the harbor porpoises (2 per week over the 
course of 8 weeks of impact pile driving) that enter the Level B zone 
in Year 1 could approach the project site closer and potentially enter 
the Level A harassment zone undetected during impact installation. 
Similarly, the Corps estimates that up to 27 of the harbor porpoises 
that enter the Level B harassment zone in Year 2 (2 per week over the 
course of 13.5 weeks of impact pile driving) could approach the project 
site closer and potentially enter the Level A harassment zone 
undetected during impact installation. These takes by Level A 
harassment could occur as one group in one day or single animals over 
multiple days. In total, the Corps has requested, and NMFS has 
authorized, take of 134 harbor porpoises in Year 1 (118 takes by Level 
B harassment and 16 takes by Level A harassment) and 190 harbor 
porpoises in Year 2 (163 takes by Level B harassment and 27 takes by 
Level A harassment) (Table 10).
Northern Elephant Seal
    Northern elephant seals have been observed near the mouth of the 
Columbia River, but there are no known haulout locations for northern 
elephant seals in the project vicinity. Given the rarity of sightings 
in and around the Columbia River, the Corps estimates that no more than 
two northern elephant seals per month may enter the project area and be 
taken by Level B harassment each year, for a total of six takes by 
Level B harassment in Year 1 and six takes by Level B harassment in 
Year 2 (Table 10).
    The largest Level A harassment zone (230 m) occurs during impact 
installation of 24-in steel pipe piles. It is unlikely that northern 
elephant seals would be found within this zone, and even more unlikely 
that northern elephant seals would be found within the Level A 
harassment zones for vibratory pile driving of any pile size (less than 
23 m for all pile types). However, even if northern elephant seals were 
encountered in the project areas, at that close range, the Corps will 
be able to detect them and implement the required shutdown measures 
before any northern elephant seals could enter the Level A harassment 
zones. Therefore, no take of northern elephant seals by Level A 
harassment is requested or authorized.

[[Page 51354]]



        Table 10--Authorized Take of Marine Mammals by Level A and Level B Harassment by Year, by Species and Stock and Percent of Take by Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              Authorized      Authorized
                  Species                    take by Level   take by Level  Total proposed              Stock                  Stock        Percent of
                                             A harassment    B harassment        take                                        abundance         stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Year 1:
    Humpback whale........................               0               6               6  California/Oregon/Washington           2,900            0.21
    Killer whale..........................               0               2               2  West Coast Transient........             349            0.57
    Harbor porpoise.......................              16             118             134  Northern Oregon/Washington            21,487            0.60
                                                                                             Coast.
    California sea lion...................               0          15,780          15,780  U.S.........................         257,606            6.13
    Steller sea lion......................               0          19,176          19,176  Eastern.....................          52,932           36.23
    Harbor seal...........................              38           3,781           3,819  Oregon/Washington Coast.....          24,732           15.44
    Northern elephant seal................               0               6               6  California Breeding.........         179,000           0.003
Year 2:
    Humpback whale........................               0               6               6  California/Oregon/Washington           2,900            0.21
    Killer whale..........................               0               2               2  West Coast Transient........             349            0.57
    Harbor porpoise.......................              27             163             190  Northern Oregon/Washington            21,487            0.88
                                                                                             Coast.
    California sea lion...................               0          23,421          23,421  U.S.........................         257,606            9.09
    Steller sea lion......................               0          29,502          29,502  Eastern.....................          52,932           55.74
    Harbor seal...........................              54           5,361           5,415  Oregon/Washington Coast.....          24,732           21.89
    Northern elephant seal................               0               6               6  California Breeding.........         179,000           0.003
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 Corps has provided in its description of the project that pile 
driving will 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, 
to minimize impacts to ESA-listed fish species, all in-water 
construction will be limited to the months of August through November.

Shutdown Zones

    Before the commencement of in-water construction activities, the 
Corps must establish shutdown zones for all 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). Pile driving must 
also not commence until all marine mammals are clear of their 
respective shutdown zones. Shutdown zones are meant to encompass the 
Level A harassment zones and therefore would vary based on the activity 
type and marine mammal hearing group (Table 11). At minimum, the 
shutdown zone for all hearing groups and all activities is 25 m. For 
in-water heavy machinery work other than pile driving (e.g., standard 
barges, etc.), if a marine mammal comes within 25 m, operations must 
cease and vessels must reduce speed to the minimum level required to 
maintain steerage and safe working conditions. This type of work could 
include, for example, the movement of the barge to the pile location or 
positioning of the pile on the substrate via a crane.
    The Corps must 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 
(see Table 11).

                                                                Table 11-- Shutdown Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Shutdown zones by hearing group (m)                       Shutdown zones
                                                         --------------------------------------------------------------------------------       for
                  Pile type and method                                                                        Phocid          Otariid      unauthorized
                                                            LF cetacean     MF cetacean     HF cetacean      pinniped        pinniped       species (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
24-in Steel pipe Pile Impact Installation...............             430              25             515          \a\ 50              25           1,000
24-in Steel pipe pile Vibratory Installation............              25              25              25              25              25           5,412
24-in Steel Sheet Pile Vibratory Installation \b\.......              40              25              55              25              25           4,642
24-in Steel Sheet Pile Vibratory Removal \b\............              25              25              25              25              25           4,642
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ 50 m is for harbor seals, shutdown zone for northern elephant seals is 235 m.
\b\ Vibratory installation and removal of 24-in steel sheet piles only applicable in Year 1. No sheet piles will be installed or removed in Year 2.


[[Page 51355]]

Protected Species Observers

    The placement of protected species observers (PSOs) during all pile 
driving activities (described in the Monitoring and Reporting section) 
must 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 must be 
delayed until the PSO is confident marine mammals within the shutdown 
zone could be detected.
Monitoring for Level A and Level B Harassment
    PSOs must monitor the Level B harassment zones to the extent 
practicable, and all of the Level A harassment zones. Monitoring zones 
provide utility for observing by establishing monitoring protocols for 
areas adjacent to the shutdown zones. Monitoring zones enable observers 
to be aware of and communicate the presence of marine mammals in the 
project areas outside the shutdown zones and thus prepare for a 
potential cessation of activity should the animal enter the shutdown 
zone.
Pre-Activity Monitoring
    Prior to the start of daily in-water construction activity, or 
whenever a break in pile driving of 30 minutes or longer occurs, PSOs 
must observe the shutdown and monitoring zones for a period of 30 
minutes. The shutdown zone is 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 11, 
pile driving activity must be delayed or halted. If pile driving is 
delayed or halted due to the presence of a marine mammal, the activity 
must not commence or resume until either the animal has voluntarily 
exited and been visually confirmed beyond the shutdown zones or 15 
minutes have passed without re-detection of the animal. When a marine 
mammal for which Level B harassment take is authorized is present in 
the Level B harassment zone, activities may begin and Level B 
harassment take will be recorded. If work ceases for more than 30 
minutes, the pre-activity monitoring of the shutdown zones must 
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

    Soft-start procedures are used to 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 are 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 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.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
required 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 action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and,
     Mitigation and monitoring effectiveness.

Visual Monitoring

    Marine mammal monitoring during pile driving activities must be 
conducted by PSOs meeting NMFS' standards and in a manner consistent 
with the following:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods must be used;
     At least one PSO must have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
     Other PSOs may substitute 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 must be designated. The lead 
observer is 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

[[Page 51356]]

     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    The Corps must have at least two PSOs stationed in the project area 
to monitor during all pile driving activities. One PSO must be 
positioned at the work site on the construction barge to observe Level 
A harassment and shutdown zones. At least one PSO must monitor from a 
boat to ensure full visual coverage of the Level B harassment zone(s) 
and alert construction crews of marine mammals entering the Level B 
harassment zone and/or approaching the Level A harassment zones. 
Additional PSOs may be employed during periods of low or obstructed 
visibility to ensure the entirety of the shutdown zones are monitored.
    Monitoring must be conducted 30 minutes before, during, and 30 
minutes after all in water construction activities. In addition, 
observers must record all incidents of marine mammal occurrence, 
regardless of distance from activity, and must 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.

Reporting

    A draft marine mammal monitoring report must be submitted to NMFS 
within 90 days after the completion of pile driving activities, or 60 
days prior to a requested date of issuance of any future IHAs for the 
project, or other projects at the same location, whichever comes first. 
The marine mammal report must 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: (a) How many and what type of piles were 
driven or removed and the method (i.e., impact or vibratory); and (b) 
the total duration of time for each pile (vibratory driving) number of 
strikes for each pile (impact driving);
     PSO locations during marine mammal monitoring; and
     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.
    For each observation of a marine mammal, the following must be 
reported:
     Name of PSO who sighted the animal(s) and PSO location and 
activity at time of sighting;
     Time of sighting;
     Identification of the animal(s) (e.g., genus/species, 
lowest possible taxonomic level, or unidentified), PSO confidence in 
identification, and the composition of the group if there is a mix of 
species;
     Distance and location of each observed marine mammal 
relative to the pile being driven or hole being drilled for each 
sighting;
     Estimated number of animals (min/max/best estimate);
     Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, etc.);
     Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted from the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones, by species; and
     Detailed information about implementation of any 
mitigation (e.g., shutdowns and delays), a description of specified 
actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    If no comments are received from NMFS within 30 days, the draft 
reports 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. All PSO datasheets and/or raw sighting data 
must be submitted with the draft marine mammal report.
    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the Corps must report the 
incident to the Office of Protected Resources (OPR) 
([email protected]), NMFS and to the West Coast Region 
(WCR) regional stranding coordinator as soon as feasible. If the death 
or injury was clearly caused by the specified activity, the Corps 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 Corps must not resume their activities until notified 
by NMFS.
    The report must include the following information:
    1. Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    2. Species identification (if known) or description of the 
animal(s) involved;
    3. Condition of the animal(s) (including carcass condition if the 
animal is dead);
    4. Observed behaviors of the animal(s), if alive;
    5. If available, photographs or video footage of the animal(s); and
    6. 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 
species listed in Table 10, given that the anticipated effects of this 
activity on these different marine mammal stocks are expected to

[[Page 51357]]

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. We 
note, though, that there are far fewer estimated takes of cetaceans 
than pinnipeds, and some additional pinniped-specific analysis is 
included.
    Pile driving activities associated with the Sand Island Pile Dikes 
Repairs 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.
    The takes from Level A and Level B harassment would be due to 
potential behavioral disturbance, TTS, and PTS. No serious injury or 
mortality is anticipated given the nature of the activities and 
measures designed to minimize the possibility of injury to marine 
mammals. The potential for harassment is minimized through the 
construction method and the implementation of the required mitigation 
measures (see Mitigation section).
    In both years, take by Level A harassment is authorized for two 
species (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 Corps 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.
    Additionally, the amount of authorized take by Level A harassment 
is very low for all marine mammal stocks and species. For both IHAs, 
for 5 of 7 affected stocks, NMFS anticipates and proposes to authorize 
no Level A harassment take over the duration of the Corps' planned 
activities; for the other 2 stocks, NMFS authorizes no more than 54 
takes by Level A harassment in any year. If hearing impairment occurs, 
it is most likely that the affected animal would lose only a few 
decibels in its hearing sensitivity. These takes of individuals by 
Level A harassment (i.e., a small degree of PTS) are not expected to 
accrue in a manner that would affect the reproductive success or 
survival of any individuals, much less result in adverse impacts on the 
species or stock.
    As described above, NMFS expects that marine mammals would likely 
move away from an aversive stimulus, especially at levels that would be 
expected to result in PTS, given sufficient notice through use of soft 
start. The Corps must also shut down pile driving activities if marine 
mammals approach within hearing group-specific zones that encompass the 
Level A harassment zones (see Table 11) further minimizing the 
likelihood and degree of PTS that would be incurred. Even absent 
mitigation, no serious injury or mortality from construction activities 
is anticipated or authorized.
    Effects on individuals that are taken by Level B harassment in the 
form of behavioral disruption, on the basis of reports in the 
literature as well as monitoring from other similar activities, 
including the Sand Island Pile Dike System Test Piles Project conducted 
by the Corps in preparation for the proposed Sand Island Pile Dikes 
Repairs Project (84 FR 61026; November 12, 2019), would likely be 
limited to reactions such as avoidance, increased swimming speeds, 
increased surfacing time, or decreased foraging (if such activity were 
occurring) (e.g., Thorson and Reyff 2006). Most likely, individuals 
would simply move away from the sound source and temporarily avoid the 
area where pile driving is occurring. If sound produced by project 
activities is sufficiently disturbing, animals are likely to simply 
avoid the area while the activities are occurring, particularly as the 
project is located on a busy waterway at the mouth of the Columbia 
River with high amounts of vessel traffic. We expect that any avoidance 
of the project areas by marine mammals would be temporary in nature and 
that any marine mammals that avoid the project areas during 
construction would not be permanently displaced. Short-term avoidance 
of the project areas and energetic impacts of interrupted foraging or 
other important behaviors is unlikely to affect the reproduction or 
survival of individual marine mammals, and the effects of behavioral 
disturbance on individuals is not likely to accrue in a manner that 
would affect the rates of recruitment or survival of any affected 
stock.
    Additionally, and as noted previously, 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 project is also not expected to have significant adverse 
effects on affected marine mammals' habitats. The project activities 
will not modify existing marine mammal habitat for a significant amount 
of time. The activities may cause some fish to leave the area of 
disturbance, thus temporarily impacting marine mammals' foraging 
opportunities in a limited portion of the foraging range; but, because 
of the short duration of the activities and the relatively small area 
of the habitat that may be affected (with no known particular 
importance to marine mammals), the impacts to marine mammal habitat are 
not expected to cause significant or long-term negative consequences. 
The shores along the Columbia River are occasionally used by harbor 
seals for pupping, but the Corps' proposed activities will occur 
outside of the harbor seal pupping season. There are no known important 
areas for other marine mammals, such as feeding or pupping areas.
    For all species and stocks, and in both years, take would occur 
within a limited, relatively confined area (the mouth of the Columbia 
River) of the stock's range. Given the availability of suitable habitat 
nearby, any displacement of marine mammals from the project areas is 
not expected to affect marine mammals' fitness, survival, and 
reproduction due to the limited geographic area that would be affected 
in comparison to the much larger habitat for marine mammals within the 
lower Columbia River and immediately outside the river along the Oregon 
and Washington coasts. Level A harassment and Level B harassment would 
be reduced to the level of least practicable adverse impact to the 
marine mammal species or stocks and their habitat through use of 
mitigation measures described herein.
    Some individual marine mammals in the project areas may be present 
and be subject to repeated exposure to sound from pile driving on 
multiple days. However, pile driving is not expected to

[[Page 51358]]

occur on every day of the in-water work window, and these individuals 
would likely return to normal behavior during gaps in pile driving 
activity within each day of construction and in between workdays. As 
discussed above, there is similar foraging and haulout habitat 
available for marine mammals within and outside of the Columbia River 
along the Washington and Oregon coasts, outside of the project area, 
where individuals could temporarily relocate during construction 
activities to reduce exposure to elevated sound levels from the 
project. Therefore, any behavioral effects of repeated or long duration 
exposures are not expected to negatively affect survival or 
reproductive success of any individuals. Thus, even repeated Level B 
harassment of some small subset of an overall stock is unlikely to 
result in any effects on rates of reproduction and survival of the 
stock.
    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 mortality or serious injury is anticipated or 
authorized for either year;
     In both years, Level A harassment is not anticipated or 
authorized for five of the seven species. For the other two species 
(one high-frequency cetacean and one phocid pinniped), the amount of 
Level A harassment is low and would be in the form of a slight degree 
of PTS in limited low frequency ranges (< 2 kHz) which are not the most 
sensitive primary hearing ranges for these species and would not 
interfere with conspecific communication or echolocation;
     For both years, Level B harassment would be in the form of 
behavioral disturbance, primarily resulting in avoidance of the project 
areas around where impact or vibratory pile driving is occurring, and 
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;
     Nearby areas of similar habitat value (e.g., foraging and 
haulout habitats) within and outside the lower Columbia River are 
available for marine mammals that may temporarily vacate the project 
areas during construction activities for both projects;
     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 from either project;
     The ensonified areas in both years 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 from either project;
     The efficacy of the mitigation measures in reducing the 
effects of the specified activities on all species and stocks for both 
projects;
     The enhanced mitigation measures (e.g., shutdown zones 
equivalent to the Level B harassment zones) to eliminate the potential 
for any take of unauthorized species; and
     Monitoring reports from similar work in the lower Columbia 
River, including previous work at the Sand Island Pile Dikes, that have 
documented little to no behavioral effect on individuals of the same 
species that could be impacted by the specified activities from both 
projects, suggesting the degree/intensity of behavioral harassment 
would be minimal.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the planned activities in Year 1 will have a negligible impact on all 
affected marine mammal species or stocks. NMFS also finds that the 
total marine mammal take from the planned activities in Year 2 will 
have a negligible impact on all affected marine mammal species or 
stocks.

Small Numbers

    As noted previously, only small numbers of incidental take 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 other than Steller sea lions, the authorized take 
in each year is below one third of the population for all marine mammal 
stocks (Table 10). In Year 1 and Year 2, the authorized take of Steller 
sea lions, as a proportion of the stock abundance is 36.23 percent and 
55.74 percent, respectively, if all takes are assumed to occur for 
unique individuals. In reality, it is unlikely that all takes would 
occur to different individuals. The project area represents a small 
portion of the stock's overall range (from Alaska to California (Muto 
et al., 2019)) and based on observations at other Steller sea lion 
haulouts, it is reasonable to expect individual animals to be present 
at the haulout and in the water nearby on multiple days during the 
activities. Therefore, it is more likely that there will be multiple 
takes of a smaller number of individuals within the project area, such 
that the number of individuals taken would be less than one third of 
the population.
    Based on the analysis contained herein of the planned activity 
(including the required 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.

National Environmental Policy Act

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

[[Page 51359]]

any extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
IHAs qualifies to be categorically excluded from further NEPA review.

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, in this case with the West Coast 
Regional Office.
    NMFS is authorizing incidental take of humpback whales from the 
Mexico and Central America DPSs, which are listed under the ESA. The 
effects of this Federal action were adequately analyzed in the NMFS 
West Coast Region's Biological Opinion and Magnuson-Stevens Fishery 
Conservation and Management Act Essential Fish Habitat Response for the 
Sand Island Pile Dike Repair Project, dated June 14, 2022, which 
concluded that the take NMFS authorizes through this IHA is not likely 
to adversely affect humpback whales from the Mexico and Central America 
DPSs or their designated critical habitat and would not jeopardize the 
continued existence of any endangered or threatened species.

Authorization

    As a result of these determinations, NMFS has issued two 
consecutive IHAs to the Corps for conducting the Sand Island Pile Dikes 
Repairs Project in the lower Columbia River, beginning in August 2023, 
with the previously mentioned mitigation, monitoring, and reporting 
requirements incorporated.

    Dated: August 16, 2022.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2022-17976 Filed 8-19-22; 8:45 am]
BILLING CODE 3510-22-P