[Federal Register Volume 88, Number 159 (Friday, August 18, 2023)]
[Notices]
[Pages 56595-56606]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-17744]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XD136]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to San Francisco Bay Area Water
Emergency Transportation Authority's Ferry Terminal Refurbishment in
Alameda, California
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an incidental harassment authorization.
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SUMMARY: In accordance with the regulations implementing the Marine
Mammal Protection Act (MMPA) as amended, notification is hereby given
that NMFS has issued an incidental harassment authorization (IHA) to
the San Francisco Bay Area Water Emergency Transportation Authority
(WETA) to incidentally harass, by Level A and Level B harassment,
marine mammals during construction activities associated with the
refurbishment of the Alameda Main Street Ferry Terminal in Alameda,
California. There are no changes from the proposed authorization to the
final authorization.
DATES: This authorization is effective from August 15, 2023, through
August 14, 2024.
ADDRESSES: Electronic copies of the application and supporting
documents, as well as a list of the references cited in this document,
may be obtained online at https://www.fisheries.noaa.gov/action/incidental-take-authorization-san-francisco-bay-area-water-emergency-transportation. In case of problems accessing these documents, please
call the contact listed below.
FOR FURTHER INFORMATION CONTACT: Alyssa Clevenstine, Office of
Protected Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are proposed or, if the taking is limited to harassment, a notice of a
proposed IHA is provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of the species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring, and reporting of the takings are set forth. The definitions
of all applicable MMPA statutory terms cited above are included in the
relevant sections below.
Summary of Request
On February 9, 2023, NMFS received a request from WETA for an IHA
to take marine mammals incidental to construction activities associated
with refurbishment of the Alameda Main Street Ferry Terminal in
Alameda, CA. Following NMFS' review of the application, WETA submitted
revised versions on March 15, April 18, May 18, and May 24, 2023. The
application was deemed adequate and complete on May 25, 2023, and the
applicant submitted a minor modification on June 12, 2023. WETA's
request is for take of harbor seals (Phoca vitulina) and California sea
lions (Zalophus californianus) by Level B harassment, and by Level A
harassment for certain activities. Neither WETA nor NMFS expect serious
injury or mortality to result from this activity and, therefore, an IHA
is appropriate. This final notice also includes a description of the
hydroacoustic monitoring report, which was accidentally omitted from
the proposed notice (88 FR 42304, June 30, 2023). There are no changes
from the proposed IHA to the final IHA.
Description of the Specified Activity
WETA plans to refurbish the Alameda Main Street Ferry Terminal in
the Oakland Inner Harbor, Alameda, CA, to update and replace ageing
ferry terminal components and structural support. WETA plans to use
vibratory extraction to remove four existing 30 inch (in) (76.2
centimeter (cm)) steel guide piles and vibratory installation to drive
nine new steel piles: two 24 in (60.9 cm) steel pipe piles with
concrete cap beams on land, one 48 in (121.9 cm) steel pipe monopile in
water, four 36 in (91.4 cm) steel guide piles in water, and two 36 in
(91.4 cm) donut fender piles in water. A maximum of 6 consecutive days
(5 days in water, 1 day on land) of piling activities will occur during
the course of construction (4-6 weeks) from August through November
2023 (Table 1). WETA plans to use vibratory pile driving and, if
necessary, impact pile driving to achieve required tip elevation for
the nine new piles. No in-air impacts to marine mammals are anticipated
from the installation of the two 24 in (60.9 cm) piles driven on land.
All project activities for which take is being requested will be
located in the Oakland Inner Harbor, Alameda (see Figure 2 in IHA
application).
A detailed description of the planned construction project is
provided in the Federal Register notice for the proposed IHA (88 FR
42304, June 30, 2023). Since that time, no changes have been made to
the planned activities. Therefore, a detailed description is not
provided here. Please refer to that Federal Register notice for the
description of the specified activity.
[[Page 56596]]
Table 1--Pile Extraction and Installation Activities
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Duration of Estimated
vibratory blows of
Pile activity Structure Pile size Piles per day Duration of activity per impact driving
(in) activity pile per pile
(minutes) (strikes) *
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Extraction................................ Removal of existing guide 30 4 1-3 45 N/A
piles.
Installation.............................. Terminal bridge and 48 1 1 45 1,015
foundation replacement.
Installation.............................. Float replacement (guide 36 6 1 45 1,015
piles and donut fender
piles).
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Note: Impact pile installation will only be used if vibratory methods are insufficient to achieve required tip elevation.
* Impact pile driving assumes approx. 20-30 minutes of driving.
Comments and Responses
A notice of NMFS' proposal to issue an IHA to WETA was published in
the Federal Register on June 30, 2023 (88 FR 42304). That notice
described, in detail, WETA's planned 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. During the 30-day public comment period, no
substantive public comments were received.
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history of the potentially affected species. NMFS
fully considered all of this information, and we refer the reader to
these descriptions, instead of reprinting the information. Additional
information regarding population trends and threats may be found in
NMFS' Stock Assessment Reports (SARs; www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more
general information about these species (e.g., physical and behavioral
descriptions) may be found on NMFS' website (https://www.fisheries.noaa.gov/find-species).
Table 2 lists all species for which take is authorized for this
activity, and summarizes information related to the population or
stock, including regulatory status under the MMPA and Endangered
Species Act (ESA) and potential biological removal (PBR), where known.
PBR is defined by the MMPA as the maximum number of animals, not
including natural mortalities, that may be removed from a marine mammal
stock while allowing that stock to reach or maintain its optimum
sustainable population (as described in NMFS' SARs). While no serious
injury or mortality is anticipated or authorized here, PBR and annual
serious injury and mortality from anthropogenic sources are included
here as gross indicators of the status of the species or stocks and
other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. Pacific SARs. All values presented in Table 2 are the most
recent available at the time of publication (including from the draft
2022 SARs) and are available online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.
Table 2--Marine Mammal Species Likely Impacted by the Specified Activities \1\
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ESA/MMPA status; Stock abundance (CV,
Common name Scientific name Stock Strategic (Y/N) Nmin, most recent PBR Annual M/SI
\2\ abundance survey) \3\ \4\
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Order Carnivora--Pinnipedia
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Family Otariidae (eared seals and
sea lions):
California sea lion............ Zalophus californianus U.S................... -/-; N 257,606 (N/A; 233,515; 14,011 >321
2014).
Family Phocidae (earless seals):
Harbor seal.................... Phoca vitulina California............ -/-; N 30,968 (0.157; 27,348; 1,641 42.8
richardii. 2012).
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\1\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy
(https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/; Committee on Taxonomy (2022)).
\2\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or
which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed under the ESA is
automatically designated under the MMPA as depleted and as a strategic stock.
\3\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\4\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, vessel strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range.
[[Page 56597]]
As indicated above, both species in Table 2 temporally and
spatially co-occur with the activity to the degree that take is
reasonably likely to occur and are also included in Table 2 of the IHA
application. No other marine mammal species are expected to occur in
the project area.
A detailed description of the species likely to be affected by this
project, including brief introductions to the species and relevant
stocks as well as available information regarding population trends and
threats, and information regarding local occurrence, were provided in
the Federal Register notice for the proposed IHA (88 FR 42304, June 30,
2023); since that time, we are not aware of any changes in the status
of these species and stocks; therefore, detailed descriptions are not
provided here. Please refer to that Federal Register notice for these
descriptions. Please also refer to the NMFS website (https://www.fisheries.noaa.gov/find-species) for generalized species accounts.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Not all marine mammal species have equal
hearing capabilities (e.g., Richardson et al., 1995, Wartzok and
Ketten, 1999, Au and Hastings, 2008). To reflect this, Southall et al.
(2007, 2019) recommended that marine mammals be divided into hearing
groups based on directly measured (behavioral or auditory evoked
potential techniques) or estimated hearing ranges (behavioral response
data, anatomical modeling, etc.). Note that no direct measurements of
hearing ability have been successfully completed for mysticetes (i.e.,
low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65
decibel (dB) threshold from the normalized composite audiograms, with
the exception for lower limits for low-frequency cetaceans where the
lower bound was deemed to be biologically implausible and the lower
bound from Southall et al. (2007) retained. Marine mammal hearing
groups and their associated hearing ranges are provided in Table 3.
Table 3--Marine Mammal Hearing Groups
[NMFS, 2018]
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Hearing group Generalized hearing range *
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Low-frequency (LF) cetaceans (baleen 7 Hz to 35 kHz.
whales).
Mid-frequency (MF) cetaceans 150 Hz to 160 kHz.
(dolphins, toothed whales, beaked
whales, bottlenose whales).
High-frequency (HF) cetaceans (true 275 Hz to 160 kHz.
porpoises, Kogia, river dolphins,
Cephalorhynchid, Lagenorhynchus
cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) 50 Hz to 86 kHz.
(true seals).
Otariid pinnipeds (OW) (underwater) 60 Hz to 39 kHz.
(sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006, Kastelein et al., 2009, Reichmuth et al.,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
The effects of underwater noise from WETA's construction activities
have the potential to result in behavioral harassment of marine mammals
in the vicinity of the project area. The notice of the proposed IHA (88
FR 42304, June 30, 2023) included a discussion of the effects of
anthropogenic noise on marine mammals and the potential effects of
underwater noise from WETA's construction activities on marine mammals
and their habitat. That information and analysis is incorporated by
reference into this final IHA determination and is not repeated here;
please refer to the notice of the proposed IHA (88 FR 42304, June 30,
2023).
Estimated Take of Marine Mammals
This section provides an estimate of the number of incidental takes
authorized through this IHA, which informed both NMFS' consideration of
``small numbers'' and the negligible impact determinations.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance, which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would primarily be by Level B harassment, as use
of the acoustic sources (i.e., vibratory removal, vibratory driving,
impact driving) has the potential to result in disruption of behavioral
patterns for individual marine mammals. There is also some potential
for permanent threshold shift (PTS) (Level A harassment) to result,
primarily for phocids because predicted auditory injury zones are
larger than for otariids. Auditory injury is unlikely to occur for
otariids. The mitigation and monitoring measures are expected to
minimize the severity of the taking to the extent practicable (see
Mitigation and Monitoring and Reporting sections).
As described previously, no serious injury or mortality is
anticipated or authorized for this activity. Below we describe how the
take numbers are estimated.
Generally speaking, we estimate take by considering: (1) acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or
[[Page 56598]]
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 authorized
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 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, Southall et al., 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 sound pressure levels (RMS SPL) of 120 dB
(referenced to 1 microPascal (re 1 [mu]Pa)) for continuous (e.g.,
vibratory pile driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa
for non-explosive impulsive (e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources. Generally speaking, Level B
harassment take estimates based on these behavioral harassment
thresholds are expected to include any likely takes by temporary
threshold shift (TTS) as, in most cases, the likelihood of TTS occurs
at distances from the source less than those at which behavioral
harassment is likely. TTS of a sufficient degree can manifest as
behavioral harassment, as reduced hearing sensitivity and the potential
reduced opportunities to detect important signals (conspecific
communication, predators, prey) may result in changes in behavior
patterns that would not otherwise occur.
WETA's construction activities include the use of continuous
(vibratory pile removal and installation) and, potentially, impulsive
(impact pile installation) sources and, therefore, the RMS SPL
thresholds of 120 and 160 dB re 1 [mu]Pa are applicable.
Level A harassment--NMFS' Technical Guidance for Assessing the
Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0)
(Technical Guidance, 2018) identifies dual criteria to assess auditory
injury (Level A harassment) to five different marine mammal groups
(based on hearing sensitivity) as a result of exposure to noise from
two different types of sources (impulsive or non-impulsive). WETA's
construction activities include the use of impulsive (impact hammer)
and non-impulsive (vibratory hammer) sources.
These thresholds are provided in Table 4 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.
Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
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PTS onset acoustic thresholds \*\ (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-Impulsive
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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.
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* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that are used in estimating the area ensonified above the
acoustic thresholds, including source levels and transmission loss (TL)
coefficient.
Pile driving activities, using an impact hammer as well as a
vibratory hammer, generate underwater noise that could result in
disturbance to marine mammals near the project area. A review of
underwater sound measurements for similar projects was conducted to
estimate the near-source sound levels for impact and vibratory pile
driving and vibratory extraction. Source levels and sound exposure
levels (SEL) for planned removal and installation activities derived
from this review are shown in Table 5.
[[Page 56599]]
Table 5--Project Sound Source Levels
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Pile size Peak SPL dB re RMS SPL dB re SEL dB re 1
Driving method Location (in) 1 [mu]Pa 1 [mu]Pa [mu]Pa \2\-sec Source
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Impact *.......................... Water................ 36 206 188 178 Caltrans 2020.
Impact *.......................... Water................ 48 208 187 174 Caltrans 2020.
Vibratory......................... Water................ [dagger] 30 200 168 168 POA 2016.
Vibratory......................... Water................ 36 200 168 168 POA 2016.
Vibratory......................... Water................ 48 200 168 168 POA 2016.
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* Attenuated condition achieved using a bubble curtain system for all impact pile driving; attenuated condition assumes a 5-dB reduction in sound.
[dagger] Vibratory driving of 36 in piles used as proxy for vibratory extraction of 30 in piles.
Level B Harassment Zone--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 topography. The general formula for underwater TL is:
TL = B * Log10 (R1/R2),
where
TL = transmission loss in dB;
B = transmission loss coefficient;
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, known as practical spreading,
which is the most appropriate assumption for WETA's planned activity in
the absence of specific modeling and site-specific information. Sound
propagation in the Oakland Inner Harbor is limited by bends in the
channel and substantial sound is not anticipated to travel beyond 4,200
m (13,780 ft) to the west (out the shipping channel into the bay) and
1,700 m (5,577 ft) east of the project site (where the channel bends
around the island of Alameda), and will be confined to the north and
south by the narrow channel of the Oakland Inner Harbor (see Figure 1
in the IHA application). Therefore, the distance for noise impacts
would be limited to 4,200 m west and 1,700 m east of the project
location. The Level A shutdown zones and Level B harassment zones for
WETA's planned activities are shown in Table 6.
Table 6--Distance to the Level A and Level B Harassment Thresholds for Pile-Driving Activities
----------------------------------------------------------------------------------------------------------------
Level A Level A Level B
Method Pile type Pile size threshold for threshold for harassment zone
(in) phocids (m) otariids (m) (m)
----------------------------------------------------------------------------------------------------------------
Impact, installation......... Steel........... 36 827 60 736.
Impact, installation......... Steel........... 48 136 10 631.
Vibratory, extraction *...... Steel........... 30 33 10 4,200 W; 1,700
E.
Vibratory, installation *.... Steel........... 36 33 10 4,200 W; 1,700
E.
Vibratory, installation *.... Steel........... 48 10 10 4,200 W; 1,700
E.
----------------------------------------------------------------------------------------------------------------
Note: Vibratory driving of 36 in piles used as proxy for vibratory extraction of 30 in piles.
* Constrained by bends in the Oakland Estuary and relatively shallow bathymetry near the shipping channel: 4,200
m (13,780 ft) west, 1,700 m (5,577 ft) east.
Level A Harassment Thresholds--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 (i.e., vibratory and impact piling), 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. Inputs used in the optional User
Spreadsheet tool, and the resulting estimated isopleths, are reported
in Table 7. The isopleths generated by the User Spreadsheet used the
same TL coefficients as the Level B harassment zone calculations, as
indicated above for each activity type. Inputs used in the User
Spreadsheet (e.g., number of piles per day, duration and/or strikes per
pile) are presented in Table 1. The maximum RMS SPL, SEL, and peak SPL
are reported in Table 7. The cumulative SEL and peak SPL were used to
calculate Level A harassment isopleths for vibratory pile driving and
extraction activities, while the single strike SEL value was used to
calculate Level A isopleths for impact pile driving activity.
[[Page 56600]]
Table 7--Sound Levels Used for Predicting Underwater Sound Impacts
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Pile Peak SPL RMS SPL SEL attenuated
Driving method Location size Peak SPL dB re RMS SPL dB re SEL dB re 1 attenuated * attenuated * * dB re 1 [mu]Pa
(in) 1 [mu]Pa 1 [mu]Pa [mu]Pa\2\-sec dB re 1 [mu]Pa dB re 1 [mu]Pa \2\-sec
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact...................... Water.......... 36 211 193 183 206 188 178
Impact...................... Water.......... 48 213 192 179 208 187 174
Vibratory................... Water.......... 36 200 168 168 NA NA NA
Vibratory................... Water.......... 48 200 168 168 NA NA NA
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Note: Using estimates for vibratory installation of 36 in (91.4 cm) steel pile as proxy for vibratory extraction of 30 in (76.2 cm) steel pile. Sound
pressure levels (SPL) measured in dB re 1 [mu]Pa at 10 meters.
* Attenuated condition assumes 5 dB reduction in source level.
NA: No additional attenuation applied to piles driven with a vibratory hammer.
Marine Mammal Occurrence
In this section we provide information about the occurrence of
marine mammals, including density or other relevant information which
will inform the take calculations.
The California Department of Transportation (Caltrans) conducted
monitoring of marine mammals in the vicinity of the San Francisco-
Oakland Bay Bridge for 16 years. From those data, Caltrans produced at-
sea density estimates for California sea lions and harbor seals
(Caltrans, 2016). Using these density estimates and the estimated Level
A and Level B harassment areas, take estimates were calculated for all
potential construction options.
WETA ferry boat captains have reported frequently seeing both
California sea lions and harbor seals in the estuary channel and within
the Oakland Inner Harbor (in-water sightings, not hauled out) but did
not report seeing either species or other marine mammals near the
Alameda Main Street Ferry Terminal dock or platform (WETA, pers.
comm.).
California sea lion--Caltrans's at-sea density estimate for
California sea lions is 0.161 animals/km\2\ for the summer-late fall
season (Caltrans, 2016). During El Ni[ntilde]o conditions, the density
of California sea lions in San Francisco Bay may be much greater than
the value used above. Development of El Ni[ntilde]o conditions in 2023
is ongoing, with chances of a strong event currently estimated at 56
percent (https://www.climate.gov, June 8, 2023). To account for the
potential increase in California sea lions within San Francisco Bay
during the project, daily take estimated has been increased by a factor
of 10 for each pile activity and type (e.g., 82 FR 17799, April 13,
2017). California sea lions have occupied docks near Pier 39 in San
Francisco (approx. 10.4 kilometers (km) (6.47 mi) west northwest) since
1987. The highest number of sea lions recorded at Pier 39 was 1,701
individuals in November 2009. Occurrence of sea lions here is typically
lowest in June (during pupping and breeding seasons) and highest in
August. Approximately 85 percent of the animals that haul out at this
site are males, and no pupping has been observed here or at any other
site in San Francisco Bay. Pier 39 is the only regularly used haul out
site in the project vicinity, but sea lions occasionally haul out on
human-made structures such as bridge piers, jetties, or navigation
buoys (Riedman, 1990).
Harbor seal--Caltrans at-sea density estimate for harbor seals is
3.957 animals/km\2\ (Caltrans, 2016). No resident harbor seals occur
within the Oakland Inner Harbor. The closest haul out to the project
area is located outside of the Oakland Inner Harbor at Alameda Point
(approx. 37.770127[deg], -122.296819[deg]), where a float was installed
by WETA in 2016 to accommodate harbor seals. This haulout can carry
approximately 80 individuals, with highest sightings occurring during
winter months. Additionally, the southern shoreline of Yerba Buena
Island (approx. 6.2 km (3.8 mi) west northwest) is a haulout site with
the highest numbers hauled out during afternoon low tides in fall and
winter months.
Take Estimation
Here we describe how the information provided above is synthesized
to produce a quantitative estimate of the take that is reasonably
likely to occur and authorized.
Incidental take is estimated for each species by estimating the
maximum number of marine mammals potentially present within a
harassment zone during active pile driving based on density estimates,
harassment zone size, and length of construction activity. Animal
exposure estimates for each species were calculated by multiplying the
estimated density of each species by the area of each harassment zone
during active each type of pile driving activity (vibratory removal,
vibratory driving, impact driving) and pile size (30 in, 36 in, 48 in).
The estimated density is based on Caltrans (2016) offshore at-sea
density and increased to account for the likely increase of animals in
a nearshore environment based on previous comments from the Marine
Mammal Commission (see Tables 3 and 4 in the IHA application and 82 FR
17799, April 13, 2017).
Maximum number of animals exposed per activity = Density x Level A or
Level B harassment area
Estimated take was calculated using the exposure estimate
multiplied by the number of days each in-water pile driving activity
will occur. An additional take of zero to two animals per day was added
to account for the potential occurrence of small groups or additional
individuals. This was done because small numbers of both species are
known to use the Oakland Inner Harbor but extensive surveys have not
been completed in the project area. Using these density estimates and
the areas within the Level A and B harassment isopleths, the take
estimates were calculated for all possible construction options and
here we show the maximum take estimates. Maximum estimated take by
Level A harassment is based on 3 days of in-water vibratory pile
removal plus 2 days of in-water impact driving, as the Level A
harassment isopleth is larger for impact driving than vibratory driving
(Table 8). Maximum estimated take by Level B harassment is based on 3
days of in-water vibratory removal plus 2 days of in-water vibratory
pile installation, as the Level B harassment isopleth for vibratory
driving is larger than for impact driving (Table 9). This results in a
conservative estimate of how many marine mammals might be present to
ensure that take estimates will not be exceeded (Table 10).
Estimated take = Maximum number of animals exposed x number of days per
activity + additional individuals
Finally, due to the probability of El Ni[ntilde]o conditions
developing throughout 2023 (https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.shtml), the daily take
estimate for California sea lions was multiplied by a factor of 10 for
each day
[[Page 56601]]
to account for a potential increase in occurrence that has been
previously documented for the species under expected climatological
conditions (see 82 FR 17799, April 13, 2017).
Table 8--Estimated Take by Level A Harassment per Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
Additional
Pile size Potential Duration of Estimated Level A take Total
Construction activity (in) Species take/day activity incidental requested Level A
(day) take (animals/day) take
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory removal........................ * 30 HASE........................ 0.04 1-3 <1 1 1-3
Vibratory removal........................ * 30 CASL........................ NA 1-3 NA NA NA
Vibratory installation................... 36 HASE........................ 0.04 1 <1 1 1
Vibratory installation................... 36 CASL........................ NA 1 NA NA NA
Vibratory installation................... 48 HASE........................ 0.001 1 <1 1 1
Vibratory installation................... 48 CASL........................ NA 1 NA NA NA
Impact driving........................... 36 HASE........................ 2.57 1 3 1 4
Impact driving........................... 36 CASL........................ 0.002 1 <1 1 1
Impact driving........................... 48 HASE........................ 0.15 1 <1 1 1
Impact driving........................... 48 CASL........................ 0.00005 1 <1 1 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All California sea lion estimates were multiplied by a factor of 10 to account for the increased occurrence of this species due to potential for
El Ni[ntilde]o conditions.
* Using estimates for vibratory installation of 36 in (91.4 cm) steel pile as proxy for vibratory extraction of 30 in (76.2 cm) steel pile.
HASE: Harbor seal density 3.957 animals/km\2\.
CASL: California sea lion density 0.161 animals/km\2\.
Table 9--Estimated Take by Level B Harassment per Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
Additional
Pile size Potential Duration of Estimated Level B take Total
Construction activity (in) Condition Species take/day activity incidental requested Level B
(day) take (animals/day) take
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory removal.............. * 30 Unattenuated...... HASE.............. 7.64 1-3 8-24 2 10-30
Vibratory removal.............. * 30 Unattenuated...... CASL.............. 3.1 1-3 1-3 2 5-15
Vibratory installation......... 36 Unattenuated...... HASE.............. 7.64 1 8 2 10
Vibratory installation......... 36 Unattenuated...... CASL.............. 3.1 1 1 2 5
Vibratory installation......... 48 Unattenuated...... HASE.............. 7.64 1 8 2 10
Vibratory installation......... 48 Unattenuated...... CASL.............. 3.1 1 1 2 5
Impact driving................. 36 Attenuated........ HASE.............. 2.33 1 3 2 5
Impact driving................. 36 Attenuated........ CASL.............. 0.9 1 <1 2 2
Impact driving................. 48 Attenuated........ HASE.............. 1.94 1 2 2 4
Impact driving................. 48 Attenuated........ CASL.............. 0.8 1 <1 2 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All California sea lion estimates were multiplied by a factor of 10 to account for the increased occurrence of this species due to potential for
El Ni[ntilde]o conditions.
* Using estimates for vibratory installation of 36 in (91.4 cm) steel pile as proxy for vibratory extraction of 30 in (76.2 cm) steel pile.
HASE: Harbor seal density 3.957 animals/km\2\.
CASL: California density 1.61 animals/km\2\.
Table 10--Estimated Take by Level A and Level B Harassment for Authorization
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum
Maximum estimated Estimate take
Species common name Scientific name Stock estimated Level B as a
Level A harassment percentage of
harassment * [dagger] population
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion [Dagger]............. Zalophus californianus...... U.S......................... 2 25 0.011
Harbor seal.............................. Phoca vitulina richardii.... California.................. 8 50 0.187
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: NMFS SARs 2015, 2021.
* Based on 3 days of vibratory removal plus 2 days of impact installation (36 in (91.4 cm), 48 in (121.9 cm) piles only).
[dagger] Based on 3 days of vibratory removal plus 2 days of vibratory installation (36 in (91.4 cm), 48 in (121.9 cm) piles only).
[Dagger] To account for the increase in California sea lion density due to potential El Ni[ntilde]o conditions, the daily take estimated from the
density has been increased by a factor of 10 for each day that pile driving or removal occurs.
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)).
[[Page 56602]]
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.
WETA must ensure that construction supervisors and crews, the
monitoring team, and relevant WETA staff are trained prior to the start
of all pile driving activities, so that responsibilities, communication
procedures, monitoring protocols, and operational procedures are
clearly understood. New personnel joining during the project must be
trained prior to commencing work.
Timing Restrictions
All piling activities shall be conducted between June 1 and
November 30, when the likelihood of sensitive fish species being
present in the work area is minimal, following U.S. Army Corps of
Engineers' (USACE) Proposed Additional Procedures and Criteria for
Permitting Projects under a Programmatic Determination of Not Likely to
Adversely Affect Select Listed Species in California (USACE, 2018).
Consistent with municipal code, noise-generating construction
activities will be limited to the hours between 0700 and 1900 Monday
through Friday, and 0800 and 1300 on Saturdays.
Protected Species Observers
The placement of protected species observers (PSOs) during all pile
driving activities (described in the Monitoring and Reporting section)
will ensure that the entire shutdown zone is visible. Should
environmental conditions deteriorate such that the entire shutdown zone
would not be visible (e.g., fog, heavy rain), pile driving will be
delayed until the PSO is confident marine mammals within the shutdown
zone could be detected.
PSOs will monitor the full shutdown zones and the Level B
harassment zones to the extent practicable. Monitoring zones provide
utility for observing by establishing monitoring protocols for areas
adjacent to the shutdown zones. Monitoring zones enable observers to be
aware of and communicate the presence of marine mammals in the project
areas outside the shutdown zones and thus prepare for a potential
cessation of activity should the animal enter the relevant shutdown
zone.
Pre- and Post-Activity Monitoring
Monitoring must take place from 30 minutes prior to initiation of
pile driving activities (i.e., pre-clearance monitoring) through 30
minutes post-completion of pile driving. Prior to the start of daily
in-water construction activity, or whenever a break in pile driving of
30 minutes or longer occurs, PSOs will observe the shutdown and
monitoring zones for a period of 30 minutes. The shutdown zone will be
considered cleared when a marine mammal has not been observed within
the zone for a 30-minute period. If a marine mammal is observed within
the shutdown zones listed in Table 11, pile driving activity will be
delayed or halted. If work ceases for more than 30 minutes, the pre-
activity monitoring of the shutdown zones will commence. A
determination that the shutdown zone is clear must be made during a
period of good visibility (i.e., the entire shutdown zone and
surrounding waters must be visible to the naked eye).
Soft-Start Procedures for Impact Driving
Soft-start procedures provide additional protection to marine
mammals by providing warning and/or giving marine mammals a chance to
leave the area prior to the hammer operating at full capacity. If
impact pile driving is necessary to achieve required tip elevation,
WETA staff and/or contractors will be required to provide an initial
set of three strikes from the hammer at reduced energy, followed by a
30-second waiting period, then two subsequent reduced-energy strike
sets. Soft-start will be implemented at the start of each day's impact
pile driving and at any time following cessation of impact pile driving
for a period of 30 minutes or longer.
Bubble Curtain for Impact Driving
WETA plans to use a bubble curtain to mitigate effects from impact
pile driving on marine mammals, and NMFS concurs with the effectiveness
of this measure. Therefore, a bubble curtain will be employed during
all impact installation of piles. The bubble curtain must distribute
air bubbles around 100 percent of the piling circumference for the full
depth of the water column. The lowest bubble ring must be in contact
with the mudline for the full circumference of the ring. The weights
attached to the bottom ring must ensure 100 percent substrate contact.
No parts of the ring or other objects may prevent full substrate
contact. Air flow to the bubblers must be balanced around the
circumference of the pile.
Shutdown Zones
WETA must establish shutdown zones for all pile driving activities.
The purpose of a shutdown zone is generally to define an area within
which shutdown of the activity would occur upon sighting of a marine
mammal (or in anticipation of an animal entering the defined area).
Shutdown zones are based upon the Level A harassment zone for each pile
size/type and driving method where applicable, as shown in Table 6. A
minimum shutdown zone of 10 meters (m) is required for all in-water
construction activities to avoid physical interaction with marine
mammals. For pile driving, the radii of the shutdown zones are rounded
to the next largest 10 m interval in comparison to the Level A
harassment zone for each activity type. If a marine mammal is observed
entering or within a shutdown zone during pile driving activity, the
activity must be stopped until there is visual confirmation that the
animal has left the zone or the animal is not sighted for a period of
15 minutes. Shutdown zones for each activity type are shown in Table
11.
All marine mammals will be monitored in the Level B harassment
zones and throughout the area as far as visual monitoring can take
place. If a marine mammal enters the Level B harassment zone, in-water
activities will continue and PSOs will document the animal's presence
within the estimated harassment zone.
[[Page 56603]]
Table 11--Shutdown and Harassment Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
Shutdown zone Shutdown zone
Method Pile type Pile size (in) for phocids for otariids Level B harassment zone (m)
(m) (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact, installation.................... Steel..................... 36 830 60 736.
Impact, installation.................... Steel..................... 48 140 10 631.
Vibratory, extraction *................. Steel..................... 30 40 10 4,200 W; 1,700 E.
Vibratory, installation *............... Steel..................... 36 40 10 4,200 W; 1,700 E.
Vibratory, installation *............... Steel..................... 48 10 10 4,200 W; 1,700 E.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Vibratory driving of 36 in (91.4 cm) piles used as proxy for vibratory extraction of 30 in (76.2 cm) piles.
* Constrained by bends in the Oakland Estuary and relatively shallow bathymetry near the shipping channel: 4,200 m (13,780 ft) west, 1, 700 m (5,577 ft)
east.
Based on our evaluation of the applicant's planned measures, NMFS
has determined that the planned mitigation measures provide the means
of effecting the least practicable impact on the affected species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Monitoring and Reporting
In order to issue an IHA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must set forth requirements pertaining to the
monitoring and reporting of such taking. The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present while
conducting the activities. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the activity; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and,
Mitigation and monitoring effectiveness.
Visual Monitoring
Marine mammal monitoring must be conducted in accordance with the
conditions in this section and this IHA. Marine mammal monitoring
during pile driving activities will be conducted by PSOs meeting NMFS'
standards and in a manner consistent with the following:
PSOs must be independent of the activity contractor (for
example, employed by a subcontractor) and have no other assigned tasks
during monitoring periods;
At least one PSO will have prior experience performing the
duties of a PSO during construction activity pursuant to a NMFS-issued
incidental take authorization;
Other PSOs may substitute other relevant experience,
education (degree in biological science or related field), or training
for prior experience performing the duties of a PSO during construction
activity pursuant to a NMFS-issued incidental take authorization;
Where a team of three or more PSOs is required, a lead
observer or monitoring coordinator must be designated. The lead
observer must have prior experience performing the duties of a PSO
during construction activity pursuant to a NMFS-issued incidental take
authorization; and
PSOs must be approved by NMFS prior to beginning any
activity subject to the IHA.
PSOs should have the following additional qualifications:
Ability to conduct field observations and collect data
according to assigned protocols;
Experience or training in the field identification of
marine mammals, including the identification of behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates, times, and reason for implementation
of mitigation (or why mitigation was not implemented when required);
and marine mammal behavior; and
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
WETA will have one to three PSOs stationed at the best possible
vantage points in the project area to monitor during all pile removal
and driving activities. Monitoring will occur from elevated locations
along the shoreline or on vessels where the entire shutdown zones are
visible. PSOs will be equipped with high quality binoculars for
monitoring and radios or cells phones for maintaining contact with work
crews. Monitoring will be conducted 30 minutes before, during, and 30
minutes after all in-water construction activities. In addition, PSOs
will record all incidents of marine mammal occurrence, regardless of
distance from activity, and will document any behavioral reactions in
concert with distance from piles being driven or removed. Pile driving
activities include the time to install or remove a single
[[Page 56604]]
pile or series of piles, as long as the time elapsed between uses of
the pile driving equipment is no more than 30 minutes.
Pre-Construction Monitoring
In addition to monitoring on days that pile removal and driving
will occur, as proposed by the applicant, WETA will conduct pre-
construction monitoring. Prior to initiation of in-water construction,
a qualified NMFS-approved PSO will conduct monitoring of marine mammals
to update existing information on species occurrence in and near the
project area, their movement patterns, and their site use. This pre-
construction monitoring will take place at least 5 days prior to the
start of in-water construction and will cover a period of at least 1
week (with at least 5 days of actual observation over a period of 4
hours each day), 2 hours in the morning at the time that construction
activities would begin and 2 hours at midday.
Hydroacoustic Monitoring
WETA will conduct hydroacoustic monitoring during all impact
driving activities. Acoustic monitoring must be conducted in accordance
with the Acoustic Monitoring Plan, to be submitted to NMFS no less than
30 days prior to commencement of pile driving activity.
The acoustic monitoring report must contain the informational
elements described in the Acoustic Monitoring Plan and, at a minimum,
must include:
Hydrophone equipment and methods: recording device,
sampling rate, distance (m) from the pile where recordings were made;
depth of water at the pile location and recording device(s);
Type and size of pile being driven, substrate type, method
of driving during recordings (e.g., hammer model and energy), and total
pile driving duration;
For all impact driving, a detailed description of the
sound attenuation device used and the duration of its use per pile;
For impact pile driving (per pile): Number of strikes and
strike rate; depth of substrate to penetrate; pulse duration and mean,
median, and maximum sound levels (dB re: 1 [micro]Pa): root mean square
sound pressure level (SPLrms), cumulative sound exposure
level (SELcum), peak sound pressure level
(SPLpeak), and single-strike sound exposure level
(SELs-s);
One-third octave band spectrum and power spectral density
plots (average per pile type or for each individual pile); and
Sound measurement data shall be provided to NMFS in
tabular spreadsheet format (Microsoft Excel or similar).
Reporting
WETA will provide the following reporting as necessary during
active pile driving activities:
The applicant will report any observed injury or mortality
as soon as feasible and in accordance with NMFS' standard reporting
guidelines. Reports will be made by phone (866-767-6114) and by email
([email protected]) and will include the following:
[cir] Time, date, and location (latitude/longitude) of the first
discovery (and updated location information if known and applicable);
[cir] Species identification (if known) or description of the
animal(s) involved;
[cir] Condition of the animal(s) (including carcass condition if
the animal is dead);
[cir] Observed behaviors of the animal(s), if alive;
[cir] If available, photographs or video footage of the animal(s);
and,
[cir] General circumstances under which the animal was discovered.
An annual report summarizing the prior year's activities
will be provided that fully documents the methods and monitoring
protocols, summarizes the data recorded during monitoring, estimates
the number of listed marine mammals that may have been incidentally
taken during project pile driving, and provides an interpretation of
the results and effectiveness of all monitoring tasks. The annual draft
report will be provided no later than 90 days following completion of
construction activities. Any recommendations made by NMFS will be
addressed in the final report, due after the IHA expires and including
a summary of all monitoring activities, prior to acceptance by NMFS.
Final reports will follow a standardized format for PSO reporting from
activities requiring marine mammal mitigation and monitoring.
All PSOs will use a standardized data entry format (see
Appendix B of the IHA application).
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 both
California sea lions and harbor seals, given that the anticipated
effects of the construction activities on these different marine mammal
stocks are expected to be similar. There is little information about
the nature or severity of the impacts, or the size, status, or
structure of any of these species or stocks that would lead to a
different analysis for these activities.
Pile driving and removal activities 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 and removal. Potential
takes could occur if individuals are present in the ensonified zone
when these activities are underway.
The authorized takes by Level A and Level B harassment would be due
to potential behavioral disturbance, TTS, and PTS. No mortality or
serious injury is anticipated given the nature of the activity 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 mitigation measures
(see Mitigation section).
The Level A harassment zones identified in Table 11 are based upon
an animal exposed to impact pile driving of
[[Page 56605]]
multiple piles in a single day. Considering duration of impact driving
each pile (up to 20 minutes) and breaks between pile installations (to
reset equipment and move pile into place), this means an animal would
have to remain within the area estimated to be ensonified above the
Level A harassment threshold for multiple hours. This is highly
unlikely given marine mammal movement throughout the area. If an animal
was exposed to accumulated sound energy above the Level A harassment
threshold, the resulting PTS would likely be small (e.g., PTS onset) at
lower frequencies where pile driving energy is concentrated, and
unlikely to result in impacts to individual fitness, reproduction, or
survival.
The nature of the project precludes the likelihood of serious
injury or mortality. For all species and stocks, take would occur
within a limited, confined area (Oakland Inner Harbor, San Francisco
Bay) of the stock's range. Level A and Level B harassment will be
reduced to the level of least practicable adverse impact through use of
mitigation measures described herein. Further, the amount of take
authorized is extremely small when compared to stock abundance.
Behavioral responses of marine mammals to pile driving at the
project site, if any, are expected to be mild and temporary. Marine
mammals within the Level B harassment zone may not show any visual cues
they are disturbed by activities or could become alert, avoid the area,
leave the area, or display other mild responses that are not observable
such as changes in vocalization patterns. Given the short duration of
noise-generating activities per day and that pile driving and removal
would occur across 6 consecutive days, any harassment would be
temporary. There are no other areas or times of known biological
importance for any of the affected species that are likely to be
impacted by the planned activities.
In addition, it is unlikely that minor noise effects in a small,
localized area of habitat would have any effect on the stocks' ability
to recover. In combination, we believe that these factors, as well as
the available body of evidence from other similar activities,
demonstrate that the potential effects of the specified activities will
have only minor, short-term effects on individuals. The specified
activities are not expected to impact rates of recruitment or survival
and will therefore not result in population-level impacts.
In summary and as described above, the following factors primarily
support our determination that the impacts resulting from this activity
are not expected to adversely affect any of the species or stocks
through effects on annual rates of recruitment or survival:
No serious injury or mortality is anticipated or
authorized;
The specified activities and associated ensonified areas
are very small relative to the overall habitat ranges of both species;
The project area does not overlap with known Biologically
Important Areas (BIAs) or ESA-designated critical habitat;
The lack of anticipated significant or long-term effects
to marine mammal habitat;
The presumed efficacy of the mitigation measures in
reducing the effects of the specified activity; and,
Monitoring reports from similar work in San Francisco Bay
have documented little to no effect on individuals of the same species
impacted by the specified activities (AECOM, 2022; AECOM, 2023).
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the monitoring and mitigation
measures, NMFS finds that the total marine mammal take from the
activity will have a negligible impact on all affected marine mammal
species or stocks.
Small Numbers
As noted previously, only take of small numbers of marine mammals
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. When the predicted number of
individuals to be taken is fewer than one-third of the species or stock
abundance, the take is considered to be of small numbers. Additionally,
other qualitative factors may be considered in the analysis, such as
the temporal or spatial scale of the activities.
The amount of take NMFS has authorized is below one-third of the
estimated stock abundances for both species (see Table 10). For both
stocks, the authorized take of individuals is less than 0.2 percent of
the abundance of the affected stock. This is likely a conservative
estimate because it assumes all takes are of different individual
animals, which is likely not the case. Some individuals may return
multiple times in a day, but PSOs would count them as separate takes if
they cannot be individually identified.
Based on the analysis contained herein of the activity (including
the mitigation and monitoring measures) and the anticipated take of
marine mammals, NMFS finds that small numbers of marine mammals would
be taken relative to the population size of the affected species or
stocks.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
determined that the total taking of affected species or stocks would
not have an unmitigable adverse impact on the availability of such
species or stocks for taking for subsistence purposes.
Endangered Species Act
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA; 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally whenever we propose to authorize take for
endangered or threatened species.
No incidental take of ESA-listed species is authorized for this
activity. Therefore, NMFS has determined that formal consultation under
section 7 of the ESA is not required for this action.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our 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 NAO 216-6A, which do not
individually or cumulatively have the potential for significant impacts
on the quality of the human environment and for which we have not
identified any extraordinary circumstances that would preclude this
categorical exclusion. Accordingly,
[[Page 56606]]
NMFS has determined that the issuance of this IHA qualifies to be
categorically excluded from further NEPA review.
Authorization
NMFS has issued an IHA to WETA for the potential harassment of
small numbers of two marine mammal species incidental to construction
activities in the Oakland Inner Harbor at Alameda, California, that
includes the previously explained mitigation, monitoring, and reporting
requirements.
Dated: August 14, 2023.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2023-17744 Filed 8-17-23; 8:45 am]
BILLING CODE 3510-22-P