[Federal Register Volume 83, Number 114 (Wednesday, June 13, 2018)]
[Notices]
[Pages 27548-27564]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-12629]



[[Page 27548]]

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

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XG067


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the Chevron Richmond Refinery Long 
Wharf Maintenance and Efficiency Project in San Francisco Bay, 
California

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

ACTION: Notice; issuance of an incidental harassment authorization.

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

SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA), as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
Chevron to incidentally take, by Level A and/or Level B harassment, 
seven species of marine mammals during the Long Wharf Maintenance and 
Efficiency Project (WMEP) in San Francisco Bay, California.

DATES: This Authorization is applicable from June 1, 2018 through May 
31, 2019.

FOR FURTHER INFORMATION CONTACT: Rob Pauline, 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: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing these 
documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

    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 issued or, if 
the taking is limited to harassment, a notice of a proposed 
authorization is provided to the public for review.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.
    The MMPA states that the term ``take'' means to harass, hunt, 
capture, kill or attempt to harass, hunt, capture, or kill any marine 
mammal.
    Except with respect to certain activities not pertinent here, 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).

Summary of Request

    On February 1, 2018, NMFS received a request from Chevron for an 
IHA to take marine mammals incidental to pile driving and pile removal 
associated with the WMEP in San Francisco Bay, California. Chevron's 
request is for take of seven species by Level A and Level B harassment. 
Neither Chevron nor NMFS expects serious injury or mortality to result 
from this activity and, therefore, an IHA is appropriate.
    NMFS has issued an IHA to Chevron authorizing the take of seven 
species by Level A and Level B harassment. Pile driving and removal 
will take 28 days and will be timed to occur within the work windows 
developed for Endangered Species Act (ESA)--listed fish species (June 1 
through November 30). The IHA is effective from June 1, 2018 through 
May 31, 2019. This IHA would cover one year of a larger project for 
which Chevron intends to request additional take authorizations for 
subsequent facets of the project.

Description of Planned Activity

    Chevron's Richmond Refinery Long Wharf (Long Wharf) located in San 
Francisco Bay, is the largest marine oil terminal in California. The 
Long Wharf has existed in its current location since the early 1900s 
(Figure 1-1 in Application). The existing configuration of these 
systems have limitations to accepting more modern, fuel efficient 
vessels with shorter parallel mid-body hulls and in some cases do not 
meet current Marine Oil Terminal Engineering and Maintenance Standards 
(MOTEMS). The purpose of the planned WMEP is to comply with current 
MOTEMS requirements and to improve safety and efficiency at the Long 
Wharf. The planned project will involve modifications at four berths 
(Berths 1, 2, 3, and 4). Modifications to the Long Wharf include 
replacing gangways and cranes, adding new mooring hooks and standoff 
fenders, adding new dolphins and catwalks, and modifying the fire water 
system at Berths 1, 2, 3 and/or 4, as well as the seismic retrofit to 
the Berth 4 loading platform. The type and numbers of piles to be 
installed, as well as those that will be removed during the 2018-2022 
period are summarized in Table 1.

[[Page 27549]]

[GRAPHIC] [TIFF OMITTED] TN13JN18.000

    The combined modifications to Berths 1 to 4 would require the 
installation of 141 new concrete piles to support new and replacement 
equipment and their associated structures. The Berth 4 loading platform 
would add eight, 60-inch diameter steel piles as part of the seismic 
retrofit. The project would also add four clusters of 13 composite 
piles each (52 total) as markers and protection of the new batter 
(driven at an angle) piles on the east side of the Berth 4 retrofit. 
The project would remove 106 existing timber piles, three existing 
22[hyphen]inch and two existing 24[hyphen]inch concrete piles. A total 
of 12 temporary piles would also be installed and removed during the 
seismic retrofit of Berth 4.
    Note that the proposed IHA will only cover pile driving and removal 
that will occur during the 2018 work season, as provided in Table 2.

                               Table 2--Pile Driving Summary for 2018 Work Season
----------------------------------------------------------------------------------------------------------------
                                                                                     Number of       Number of
                   Pile type                            Pile driver type               piles       driving days
----------------------------------------------------------------------------------------------------------------
36-inch steel template pile...................  Vibratory.......................               8               2
Concrete pile removal.........................  Vibratory.......................               5               1
24-inch concrete..............................  Impact..........................               8               8
14-inch H pile installation (for temporary      Vibratory/Impact *..............              36              12
 fenders).
Timber pile removal...........................  Vibratory.......................              53               5
----------------------------------------------------------------------------------------------------------------
* A vibratory driver will be preferentially used for installation of the temporary H piles. In the event that
  the pile hits a buried obstruction and can no longer be advanced with a vibratory driver, and impact hammer
  may be used.


[[Page 27550]]

    These actions could produce underwater sound at levels that could 
result in the injury or behavioral harassment of marine mammal species. 
A detailed description of Chevron's planned project is provided in the 
Federal Register notice for the proposed IHA (83 FR 18802; April 30, 
2018). Since that time, no changes have been made to the planned 
project activities. Therefore, a detailed description is not provided 
here. Please refer to that Federal Register notice for the description 
of the specific activity.

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to Chevron was 
published in the Federal Register on April 30, 2018 (83 FR 18802). That 
notice described, in detail, Chevron's activity, the marine mammal 
species that may be affected by the activity, the anticipated effects 
on marine mammals and their habitat, proposed amount and manner of 
take, and proposed mitigation, monitoring and reporting measures. 
During the 30-day public comment period, NMFS received one comment 
letter from the Marine Mammal Commission (Commission); the Commission's 
recommendations and our responses are provided here, and the comments 
have been posted online at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm.
    Comment: The Commission commented that the method NMFS used to 
estimate the numbers of takes during the proposed activities, which 
summed fractions of takes for each species across project days, does 
not account for and negates the intent of NMFS' 24-hour reset policy. 
The Commission also recommends that NMFS develop and share guidance on 
this issue.
    Response: NMFS will share the guidance with the Commission 
following the completion of internal review and looks forward to 
discussing the issue with them in the future.
    Comment: The Commission requested clarification of certain issues 
associated with NMFS's notice that one-year renewals could be issued in 
certain limited circumstances and expressed concern that the process 
would bypass the public notice and comment requirements. The Commission 
also suggested that NMFS should discuss the possibility of renewals 
through a more general route, such as a rulemaking, instead of notice 
in a specific authorization. The Commission further recommended that if 
NMFS did not pursue a more general route, that the agency provide the 
Commission and the public with a legal analysis supporting our 
conclusion that this process is consistent with the requirements of 
section 101(a)(5)(D) of the MMPA.
    Response: The process of issuing a renewal IHA does not bypass the 
public notice and comment requirements of the MMPA. The notice of the 
proposed IHA expressly notifies the public that under certain, limited 
conditions an applicant could seek a renewal IHA for an additional 
year. The notice describes the conditions under which such a renewal 
request could be considered and expressly seeks public comment in the 
event such a renewal is sought. Importantly, such renewals would be 
limited to where the activities are identical or nearly identical to 
those analyzed in the proposed IHA, monitoring does not indicate 
impacts that were not previously analyzed and authorized, and the 
mitigation and monitoring requirements remain the same, all of which 
allow the public to comment on the appropriateness and effects of a 
renewal at the same time the public provides comments on the initial 
IHA. NMFS has, however, modified the language for future proposed IHAs 
to clarify that all IHAs, including renewal IHAs, are valid for no more 
than one year and that the agency would consider only one renewal for a 
project at this time. In addition, notice of issuance or denial of a 
renewal IHA would be published in the Federal Register, as are all 
IHAs. Last, NMFS will publish on our website a description of the 
renewal process before any renewal is issued utilizing the new process.
    Comment: The Commission recommended that NMFS review more 
thoroughly both the applications prior to deeming them complete and its 
notices prior to submitting them for publication in the Federal 
Register and that NMFS better evaluate the proposed exclusion/shut-down 
zones that are to be implemented for each proposed incidental take 
authorization.
    Response: NMFS thanks the Commission for its recommendation.
    Comment: The Commission expressed concern about what they assert is 
the lack of adequate time to provide public comments as well as the 
abbreviated timeframes during which NMFS is able to address public 
comments. The Commission recommended that NMFS ensure that it publishes 
and finalizes proposed incidental harassment authorizations 
sufficiently before the planned start date of the proposed activities 
to ensure full consideration is given to all comments received.
    Response: NMFS provided the required 30-day notice for public 
comment, and has adequately considered all public comments received in 
making the necessary findings.

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. 
Additional information regarding population trends and threats may be 
found in NMFS's Stock Assessment Reports (SAR; www.nmfs.noaa.gov/pr/sars/) and more general information about these species (e.g., physical 
and behavioral descriptions) may be found on NMFS's website. We 
provided a description of the specified activity in our Federal 
Register notice announcing the proposed authorization (83 FR 18802; 
April 30, 2018). Please refer to that document; we provide only a 
summary table here (Table 3).

                                     Table 3--Marine Mammals Potentially Present in the Vicinity of the Project Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      ESA/MMPA status;    Stock abundance (CV,
            Common name                  Scientific name              Stock            Strategic (Y/N)     Nmin, most recent        PBR      Annual M/SI
                                                                                             \1\         abundance survey) \2\                   \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Family Eschrichtiidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray whale.........................  Eschrichtius robustus.  Eastern North Pacific.  -/-; (N)..........  20,990 (0.05, 20,125,          624          132
                                                                                                          2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 27551]]

 
                                                                    Family Balaenidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Family Delphinidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bottlenose dolphin.................  Tursiops truncatus....  California Coastal....  -/-;(N)...........  453 (0.06, 346, 2011)          2.7   [gteqt]2.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocoenidae (porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor porpoise....................  Phocoena phocoena.....  San Francisco-Russian   -/-;(N)...........  9,886 (0.51, 6,625,             66            0
                                                              River Stock.                                2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                      Family Otariidae (eared seals and sea lions)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion................  Zalophus californianus  Eastern U.S. stock....  -/-;(N)...........  296,750 (-, 153,337,         9,200          389
                                                                                                          2011).
Northern fur seal..................  Callorhinus ursinus...  California stock......  -/-;(N)...........  14,050 (-, 7,524,              451          1.8
                                                                                                          2013).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pacific harbor seal................  Phoca vitulina........  California stock......  -/-;(N)...........  30,968 (-,27,348,            1,641           43
                                                                                                          2012).
Northern elephant seal.............  Mirounga                California Breeding     -/-;(N)...........  179,000 (-, 81,368,          4,882          8.8
                                      angustirostris.         stock.                                      2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
  stock abundance. In some cases, CV is not applicable. For certain stocks of pinnipeds, abundance estimates are based upon observations of animals
  (often pups) ashore multiplied by some correction factor derived from knowledge of the species' (or similar species') life history to arrive at a best
  abundance estimate; therefore, there is no associated CV. In these cases, the minimum abundance may represent actual counts of all animals ashore.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.

    Note that while humpback whales and Guadalupe fur seals have been 
observed in the Bay, their typical temporal and/or spatial occurrence 
is such that take is not expected to occur, and they are not discussed 
further beyond the explanation provided here.
    Humpback whales are rare, though well-publicized, visitors to the 
interior of San Francisco Bay. A humpback whale journeyed through the 
Bay and up the Sacramento River in 1985 and re-entered the Bay in the 
fall of 1990, stranding on mudflats near Candlestick Park (Fimrite 
2005). In May 2007, a humpback whale mother and calf spent just over 
two weeks in San Francisco Bay and the Sacramento River before finding 
their way back out to sea. Although it is possible that a humpback 
whale will enter the Bay and find its way into the project area during 
construction activities, their occurrence is unlikely. Guadalupe fur 
seals occasionally range into the waters of Northern California and the 
Pacific Northwest. The Farallon Islands (off central California) and 
Channel Islands (off southern California) are used as haulouts during 
these movements (Simon 2016). Juvenile Guadalupe fur seals occasionally 
strand in the vicinity of San Francisco, especially during El 
Ni[ntilde]o events. Most strandings along the California coast are 
animals younger than two years old, with evidence of malnutrition (NMFS 
2017c). In the rare event that a Guadalupe fur seal is detected within 
the Level A or Level B harassment zones, work will cease until the 
animal has left the area.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    We provided a description of the anticipated effects of the 
specified activity on marine mammals in our Federal Register notice 
announcing the proposed authorization (83 FR 18802; April 30, 2018). 
Please refer to that document for our detailed analysis; we provide 
only summary information here.
    The introduction of anthropogenic noise into the aquatic 
environment from pile driving and removal is the primary means by which 
marine mammals may be harassed from Chevron's specified activity. The 
effects of pile driving noise on marine mammals are dependent on 
several factors, including, but not limited to, sound type (e.g., 
impulsive vs. non-impulsive), the species, age and sex class (e.g., 
adult male vs. mom with calf), duration of exposure, the distance 
between the pile and the animal, received levels, behavior at time of 
exposure, and previous history with exposure (Southall et al., 2007, 
Wartzok et al., 2004). Animals exposed to natural or anthropogenic 
sound may experience physical and behavioral effects, ranging in 
magnitude from none to severe (Southall et al., 2007). In general, 
exposure to pile driving noise has the potential to result in auditory 
threshold shifts (permanent threshold shift (PTS) and temporary 
threshold shift (TTS)) and behavioral reactions (e.g., avoidance, 
temporary cessation of foraging and vocalizing, changes in dive 
behavior). No new permanent impacts to habitats used by marine mammals 
would result from the project. Some short-term impacts to prey 
availability (e.g., fish) and minor impacts to the immediate substrate 
may occur as a result of increased turbidity from pile installation and 
removal but the effects are expected to be temporary and minimal.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform both NMFS' consideration 
of small numbers and the negligible impact determination.
    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

[[Page 27552]]

(i) has the potential to injure a marine mammal or marine mammal stock 
in the wild (Level A harassment); or (ii) has the potential to disturb 
a marine mammal or marine mammal stock in the wild by causing 
disruption of behavioral patterns, including, but not limited to, 
migration, breathing, nursing, breeding, feeding, or sheltering (Level 
B harassment).
    Authorized takes would primarily be by Level B harassment, as use 
of the acoustic source (i.e., pile driving) has the potential to result 
in disruption of behavioral patterns for individual marine mammals. 
There is also some potential for auditory injury (Level A harassment) 
to result, primarily for high frequency species and a single phocid 
species due to larger predicted auditory injury zones. Auditory injury 
is unlikely to occur for low-frequency, mid-frequency species, or 
pinniped groups, with the exception of harbor seals. The mitigation and 
monitoring measures are expected to minimize the severity of such 
taking to the extent practicable.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Described in the most basic way, 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) and the number of days of activities. Below, we describe these 
components in more detail and present the authorized take estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed 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 for non-explosive sources--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 (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 decibel (dB) re 1 micro pascal ([mu]Pa) root 
mean square (rms) for continuous (e.g. vibratory pile-driving, 
drilling) and above 160 dB re 1 [mu]Pa (rms) for non-explosive 
impulsive (e.g., seismic airguns) or intermittent (e.g., scientific 
sonar) sources. For in-air sounds, NMFS predicts that pinnipeds exposed 
above received levels of 100 dB re 20 [mu]Pa (rms) and harbor seals 
exposed above 90 dB re 20 [mu]Pa (rms) will be behaviorally harassed.
    Chevron's planned activity includes the use of continuous 
(vibratory driving) and impulsive (impact driving) sources, and 
therefore the 120 and160 dB re 1 [mu]Pa (rms) are applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Technical Guidance, 2016) 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 applicant's planned activity includes the use of impulsive (impact 
driving) and non-impulsive (vibratory driving) sources.
    These thresholds are provided in Table 4. The references, analysis, 
and methodology used in the development of the thresholds are described 
in NMFS 2016 Technical Guidance, which may be accessed at: http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
BILLING CODE 3510-22-P

[[Page 27553]]

[GRAPHIC] [TIFF OMITTED] TN13JN18.001

BILLING CODE 3510-22-C

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds.
    Pile driving will generate underwater noise that potentially could 
result in disturbance to marine mammals swimming by the project area. 
Transmission loss (TL) underwater is the decrease in acoustic intensity 
as an acoustic pressure wave propagates out from a source until the 
source becomes indistinguishable from ambient sound. TL parameters vary 
with frequency, temperature, sea conditions, current, source and 
receiver depth, water depth, water chemistry, and bottom composition 
and topography. A standard sound propagation model, the Practical 
Spreading Loss model, was used to estimate the range from pile driving 
activity to various expected SPLs at potential project structures. This 
model follows a geometric propagation loss based on the distance from 
the driven pile, resulting in a 4.5 dB reduction in level for each 
doubling of distance from the source. In this model, the SPL at some 
distance away from the source (e.g., driven pile) is governed by a 
measured source level, minus the TL of the energy as it dissipates with 
distance. The TL equation is:
TL = 15log10(R<INF>1</INF>/R<INF>2</INF>)


Where:

TL is the transmission loss in dB,
R<INF>1</INF> is the distance of the modeled SPL from the driven 
pile, and
R<INF>2</INF> is the distance from the driven pile of the initial 
measurement.

    The degree to which underwater noise propagates away from a noise 
source is dependent on a variety of factors, most notably by the water 
bathymetry and presence or absence of reflective or absorptive 
conditions including the sea surface and sediment type. The TL model 
described above was used to calculate the expected noise propagation 
from both impact and vibratory pile driving, using representative 
source levels to estimate the zone of influence (ZOI) or area exceeding 
specified noise criteria.

[[Page 27554]]

Source Levels

    Sound source levels from the Chevron site were not available. 
Therefore, literature values published for projects similar to the 
Chevron project were used to estimate source levels that could 
potentially be produced. Results are shown in Table 5.
    Modifications at the four berths require the placement of new 24-
inch diameter square concrete piles. Approximately one to two of these 
piles would be installed in one workday, using impact driving methods. 
Based on measured blow counts for 24-inch concrete piles driven at the 
Long Wharf Berth 4 in 2011, installation for each pile could require up 
to approximately 300 blows and 1.5 second per blow average over a 
duration of approximately 20 minutes per pile, with 40 minutes of pile 
driving time per day if two piles are installed. To estimate the noise 
effects of the 24-inch square concrete piles, the general values 
provided by Caltrans (2015a) are shown in Table 5.
    To estimate the noise effects of impact driving of 14-inch steel H 
piles, the values provided by Caltrans were also utilized. These source 
values are 208 dB peak, 187 rms, and 177 dB SEL (single strike). Based 
on these levels, impact driving of the 14-inch steel H piles is 
expected to produce underwater sound exceeded the Level B 160 dB RMS 
threshold over a distance of 631 meters.
    During construction, temporary fendering would be installed at 
Berth 2 which will be supported by 36 steel 14-inch steel H piles. It 
is estimated that each pile could be driven in five (5) minutes. Two 
(2) to four (4) piles would be installed in any single workday for a 
total of approximately 12 days of installation. For the purposes of 
calculating the distance to Level A thresholds, four piles per day is 
assumed. The piles would be removed after the permanent fenders are in 
place. A vibratory hammer would be used to vibrate the piles to 
facilitate pulling them from the mud. The best match for estimated 
source levels is the Port of Anchorage pile driving test project. 
During vibratory pile driving associated with the Anchorage project, 
peak noise levels ranged from 165 to 175 dB, and the RMS ranged between 
152 and 168 dB, both measured at approximately 15 meters (50 ft) 
(Caltrans 2015a).
    The source levels for vibratory installation of 36-inch temporary 
steel piles were from the Explosive Handling Wharf-2 (EHW-2) project 
located at the Naval Base Kitsap in Bangor, Washington as stated in 
Caltrans (2015a). During vibratory pile driving measured peak noise 
levels were approximately 180 dB, and the RMS was approximately 169 dB 
at a 10 meter (33ft) distance. These temporary piles would require a 
drive time per pile of approximately 10 minutes. Up to four (4) of 
these piles could be installed in any single workday for a total of 40 
minutes.
    The most applicable source values for wooden pile removal were 
derived from measurements taken at the Port Townsend dolphin pile 
removal in Washington. During vibratory pile extraction associated with 
this project, which occurred under similar circumstances, measured peak 
noise levels were approximately 164 dB, and the RMS was approximately 
150 dB (WSDOT 2011). Applicable sound values for the removal of 
concrete piles could not be located, but they are expected to be 
similar to the levels produced by wooden piles described above, as they 
are similarly sized, non-metallic, and will be removed using the same 
methods.
    During construction, 106 16-inch timber piles, and seven 18 to 24-
inch square concrete piles would be removed. Up to twelve of these 
piles could be extracted in one workday. Extraction time needed for 
each pile may vary greatly, but could require approximately 400 seconds 
(approximately 7 minutes).

 Table 5--The Sound Levels (dB Peak, dB RMS, and dB sSEL) Expected to be Generated by Each Hammer and Pile Type
----------------------------------------------------------------------------------------------------------------
                                                                                                     Estimated
                                                                     Estimated       Estimated     single strike
             Type of pile                      Hammer type        pressure level  pressure level  sound exposure
                                                                     (dB peak)       (dB RMS)     level (dB SEL)
----------------------------------------------------------------------------------------------------------------
24-inch sq. concrete..................  Impact..................             188             176             166
14-inch Temporary steel H-pile........  Impact..................             208         \1\ 187             177
14-inch Temporary steel H-pile........  Vibratory...............             180         \2\ 168  ..............
36-inch Steel Pipe....................  Vibratory...............             180             169  ..............
Wood and concrete pile extraction.....  Vibratory...............             164         \3\ 150  ..............
----------------------------------------------------------------------------------------------------------------
\1\ SL was based on an assumed 10-dB difference between the SELs-s and SPLrms SLs. The SPLrmsSL was not reported
  in Caltrans.
\2\ Measured at 14 m.
\3\ Measured at 16 m.

    When NMFS Technical Guidance (2016) was published, in recognition 
of the fact that ensonified area/volume could be more technically 
challenging to predict because of the duration component in the new 
thresholds, NMFS developed a User Spreadsheet that includes tools to 
help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which will result in some degree of 
overestimate of Level A take. However, these tools offer the best way 
to predict appropriate isopleths when more sophisticated 3D modeling 
methods are not available, and NMFS continues to develop ways to 
quantitatively refine these tools, and will qualitatively address the 
output where appropriate. For stationary sources NMFS User Spreadsheet 
predicts the closest distance at which, if a marine mammal remained at 
that distance the whole duration of the activity, it would not incur 
PTS. Inputs used in the User Spreadsheet, and the resulting isopleths 
are reported below.
    Table 6 shows the inputs that were used in the User Spreadsheet to 
determine cumulative PTS Thresholds. Table 7 shows the Level A 
Isopleths as determined utilizing inputs from Table 6. Level B 
isopleths for impact and vibratory driving and extraction are shown in 
Table 8.

[[Page 27555]]



                                                          Table 6--Inputs for User Spreadsheet
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                        E.1: Impact pile        E.1: Impact pile
                                       driving (stationary     driving (stationary   A: Stationary source:  A: Stationary source:  A: Stationary source:
        Spreadsheet tab used           source: impulsive,      source: impulsive,       non- impulsive,        non- impulsive,        non- impulsive,
                                          intermittent)           intermittent)            continuous             continuous             continuous
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pile Type and Hammer Type..........  24-inch sq. concrete    14-inch Steel H-pile..  14-inch Steel H-pile.  36-in steel..........  Wood concrete pile
                                      piles.                                                                                        extraction.
Source Level.......................  166 (Single strike/     177 (Single strike/     168 RMS..............  169 RMS..............  150 RMS.
                                      shot SEL).              shot SEL).
Weighting Factor Adjustment (kHz)..  2.....................  2.....................  2.5..................  2.5..................  2.5.
Number of strikes in 1 h OR number   300...................  200...................  NA...................  NA...................  NA.
 of strikes per pile.
Activity Duration (h) within 24-h    2 piles...............  4 piles...............  0.333................  0.6667...............  1.333.
 period OR number of piles per day.
Propagation (xLogR)................  15....................  15....................  15...................  15...................  15.
Distance of source level             10....................  10....................  14...................  10...................  16.
 measurement (meters).
--------------------------------------------------------------------------------------------------------------------------------------------------------


                Table 7--Radial Distances to Level A Isopleth During Impact and Vibratory Driving
----------------------------------------------------------------------------------------------------------------
                                                             Distance in meters (feet)
                                 -------------------------------------------------------------------------------
 Project element requiring pile                                        High-
          installation             Low-frequency   Mid-frequency     frequency        Phocid          Otariid
                                     cetaceans       cetaceans       cetaceans       pinnipeds       pinnipeds
----------------------------------------------------------------------------------------------------------------
                                                 Impact Driving
----------------------------------------------------------------------------------------------------------------
24-inch square concrete (1-2 per        52 (171)           2 (6)        62 (204)         28 (92)           2 (7)
 day)...........................
14-inch steel H pile (4 per day.     343 (1,124)         12 (40)     408 (1,339)       183 (602)         13 (44)
----------------------------------------------------------------------------------------------------------------
                                          Vibratory Driving/Extraction
----------------------------------------------------------------------------------------------------------------
14-inch steel H pile (4 per day)         13 (46)           1 (3)         20 (66)          8 (26)           1 (3)
36-inch steel pipe pile (4 per           18 (58)           2 (6)         26 (86)         11 (35)           1 (2)
 day)...........................
Wood and concrete pile                     2 (5)          <1 (3)          4 (13)           2 (6)          <1 (3)
 extraction (12 per day)........
----------------------------------------------------------------------------------------------------------------


    Table 8--Radial Distances to Level B Isopleths During Impact and
                            Vibratory Driving
------------------------------------------------------------------------
                                                          Distance to
                      Pile type                          threshold in
                                                         meters (feet)
------------------------------------------------------------------------
                    Impact Driving (160 dB threshold)
------------------------------------------------------------------------
24[dash]inch square concrete........................           117 (382)
14-inch steel H pile................................         631 (2,070)
------------------------------------------------------------------------
             Vibratory Driving/Extraction (120 dB threshold)
------------------------------------------------------------------------
14-inch steel H pile................................     22,188 (72,795)
36-inch steel pipe pile.............................     18,478 (60,609)
Wood and concrete pile extraction...................       1,600 (5,249)
------------------------------------------------------------------------

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    San Francisco Bay has five known harbor seal haulout sites that 
include Alcatraz Island, Castro Rocks, Yerba Buena Island, Newark 
Slough, and Mowry Slough. Yerba Buena Island, Alcatraz and Castro Rocks 
are within or near the areas within ensonified Level B zones. Castro 
Rocks is the largest harbor seal haulout site in the northern part of 
San Francisco Bay and is the second largest pupping site in the Bay 
(Green et al. 2002). The pupping season is from March to June in San 
Francisco Bay. During the molting season (typically June-July and 
coincides with the period when piles will be driven) as many as 
approximately 130 harbor seals on average have been observed using 
Castro Rocks as a haulout. Harbor seals are more likely to be hauled 
out in the late afternoon and evening, and are more likely to be in the 
water during the morning and early afternoon (Green et al. 2002). 
However, during the molting season, harbor seals spend more time hauled 
out and tend to enter the water later in the evening. During molting, 
harbor seals can stay onshore resting for an average of 12 hours per 
day during the molt compared to around 7 hours per day outside of the 
pupping/molting seasons (NPS 2014). Tidal stage is a major controlling 
factor of haulout usage at Castro Rocks with more seals present during 
low tides than high tide periods since it is completely underwater at 
high tide twice per day (Green et al. 2002). Additionally, the number 
of seals hauled out at Castro Rocks also varies with the time of day, 
with proportionally more animals hauled out during the nighttime hours 
(Green et al. 2002). Therefore, the number of harbor

[[Page 27556]]

seals in the water around Castro Rocks will vary throughout the work 
period. However, it is likely that all seals hauled out at the site 
will be exposed to project related underwater noise at some point each 
day. The number of harbor seals located at Castro Rocks is based on the 
highest mean plus the standard error of harbor seals observed at Castro 
Rocks during recent annual surveys conducted by the National Park 
Service (NPS) (Codde, S. and S. Allen. 2013, 2015, and 2017), resulting 
in a value of 176 seals. The same NPS survey determined that harbor 
seal population in the Central Bay at Alcatraz and Yerba Buena Island 
is approximately 167 seals (Codde, S. and S. Allen. 2013, 2015, and 
2017).
    California sea lions haul out primarily on floating docks at Pier 
39 in the Fisherman's Wharf area of the San Francisco Marina, 
approximately 12.5 kilometer (km) (7.8 miles (mi)) southwest of the 
project area. Based on counts done in 1997 and 1998, the number of 
California sea lions that haul out at Pier 39 fluctuates with the 
highest occurrences in August and the lowest in June. In addition to 
the Pier 39 haulout, California sea lions haul out on buoys and similar 
structures throughout the Bay. They are seen swimming off mainly the 
San Francisco and Marin shorelines within the Bay but may occasionally 
enter the project area to forage. Over the monitoring period for the 
Richmond-San Rafael Bridge RSRB, monitors sighted at least 90 
California sea lions in the North Bay and at least 57 in the Central 
Bay (Caltrans 2012). During monitoring for the San Francisco-Oakland 
Bay Bridge (SFOBB) Project in the central Bay, 69 California sea lions 
were observed in the vicinity of the bridge over a 17-year period from 
2000-2017 (Caltrans 2018), and from these observations, an estimated 
density of 0.161 animals per square kilometer (km\2\) is derived 
(Caltrans 2018).
    A small but growing population of harbor porpoises utilizes San 
Francisco Bay. Harbor porpoises are typically spotted in the vicinity 
of Angel Island and the Golden Gate (6 and 12 km southwest 
respectively) with lesser numbers sighted in the vicinity of Alcatraz 
and around Treasure Island (Keener 2011). Porpoises but may utilize 
other areas in the Central Bay in low numbers, including the planned 
project area. However, harbor porpoise are naturally inclined to remain 
near the shoreline areas and downstream of large landmasses as they are 
constantly foraging. For this reason, the project area would present a 
less than likely area to observe harbor porpoise as they would either 
need to traverse the perimeter of the Bay to arrive there, or would 
have to swim through the open Bay. Both scenarios are possible, but 
would represent uncommon behavior. Based on monitoring conducted for 
the SFOBB project, between 2000-2017 an in-water density of 0.031 
animals per km\2\ estimated by Caltrans for this species. However, 
porpoise occurrence increased significantly in 2017 resulting in a 2017 
only density of 0.167 animals per km\2\ (Caltrans 2018).
    Small numbers of northern elephant seals haul out or strand on 
coastline within the Central Bay. Monitoring of marine mammals in the 
vicinity of the SFOBB has been ongoing for 15 years; from those data, 
Caltrans has produced an estimated at-sea density for northern elephant 
seal of 0.06 animal per km\2\ (Caltrans, 2015b). Most sightings of 
northern elephant seal in San Francisco Bay occur in spring or early 
summer, and are less likely to occur during the periods of in-water 
work for this project. As a result, densities during pile driving for 
the planned action would be much lower.
    The incidence of northern fur seal in San Francisco Bay depends 
largely on oceanic conditions, with animals more likely to strand 
during El Ni[ntilde]o events. The likelihood of El Ni[ntilde]o 
conditions occurring in 2018 is currently low, with La Ni[ntilde]a or 
neutral conditions expected to develop (NOAA, 2018).
    The range of the bottlenose dolphin has expanded northward along 
the Pacific Coast since the 1982-1983 El Ni[ntilde]o (Carretta et al. 
2013, Wells and Baldridge 1990). They now occur as far north as the San 
Francisco Bay region and have been observed along the coast in Half 
Moon Bay, San Mateo, Ocean Beach in San Francisco, and Rodeo Beach in 
Marin County. Observations indicate that bottlenose dolphin 
occasionally enter San Francisco Bay, sometimes foraging for fish in 
Fort Point Cove, just east of the Golden Gate Bridge (Golden Gate 
Cetacean Research 2014). Transient individuals of this species 
occasionally enter San Francisco Bay, but observations indicate that 
they usually remain in proximity to the Golden Gate near the mouth of 
the Bay. Beginning in 2015, two individuals have been observed 
frequently in the vicinity of Oyster Point, located south of San 
Francisco (GGCR, 2018; Perlman, 2017). Bottlenose dolphins are being 
observed in San Francisco bay more frequently in recent years. Groups 
with an average size of five animals have been observed entering the 
Bay in the vicinity of Yerba Buena Island at a rate of once per week. 
They usually are observed over two week spans and then depart for an 
extended period of time (NMFS, 2017).
    Gray whales occasionally enter the Bay during their northward 
migration period, and are most often sighted in the Bay between 
February and May. Most venture only about 2 to 3 km (about 1-2 mi) past 
the Golden Gate, but gray whales have occasionally been sighted as far 
north as San Pablo Bay. Pile driving is not expected to occur during 
this time, and gray whales are not likely to be present at other times 
of year.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    The following assumptions are made when estimating potential 
incidences of take:
    <bullet> All marine mammal individuals potentially available are 
assumed to be present within the relevant area, and thus incidentally 
taken;
    <bullet> An individual can only be taken once during a 24-h period;
    <bullet> Exposures to sound levels at or above the relevant 
thresholds equate to take, as defined by the MMPA.
    Limited density data is available for marine mammal species in San 
Francisco Bay. Estimates here are determined using data taken during 
marine mammal monitoring associated with RSRB retrofit project, the San 
Francisco-Oakland Bay Bridge replacement project, and other marine 
mammal observations for San Francisco Bay. For Pacific harbor seal, 
data was also derived from recent annual surveys of haulouts in the Bay 
conducted by the National Park Service (Codde, S. and S. Allen. 2013, 
2015, and 2017).

Pacific Harbor Seal

    As noted above, take estimates are based on the highest mean plus 
the standard error of harbor seals observed by NPS at Castro Rocks 
which equals 176 animals (Codde, S. and S. Allen. 2013, 2015, and 
2017). Castro Rocks is inundated with water twice/day during the high 
tides. So during every work day (7 a.m. to 7 p.m.) the entire haulout 
will be in the water twice per day. Of these 176 seals, the proportion 
that may enter the areas over which the Level B harassment thresholds 
may be exceeded are estimated as follows:
    <bullet> Impact driving of 24-inch concrete piles at all Berths: It 
is assumed that 10 percent of the animals that enter the water from 
Castro Rocks will enter the small Level B zones associated with this 
pile type as shown in Figure 6-1 in the application. Thus, it is 
estimated that up to 17.6 individuals per day could be exposed (176/10 
= 17.6) by entering the Level B harassment zone to the south of Castro 
Rocks;

[[Page 27557]]

    <bullet> Impact driving of 14-inch steel H piles: Impact driving 
would only occur in the event that a pile encounters an obstruction 
such as an old timber pile beneath the mud line, which is unlikely to 
occur. These piles will be preferentially driven with a vibratory 
driver. Therefore, Level B take for this activity is based on 
installation using vibratory driver. Level A take is based on 
installation using impact driving. For the purposes of calculating 
Level A take, as a proportion of Level B take, it is assumed that 
approximately 25 percent of the 176 harbor seals using Castro Rocks 
could approach and be subject to Level B harassment due to the limited 
amount of time impact driving is expected to occur as well as the size 
and location of the Level B isopleth (Figure 6-2 in application). 
Therefore, it is assumed that up to 44 individuals per day could be 
exposed when this activity is being conducted;
    <bullet> Vibratory driving and removal of the 36-inch steel pipe 
piles at Berth 4: Isopleths for this vibratory driving encompass Castro 
Rocks, therefore it is assumed that all of the estimated 176 animals in 
the water, could be exposed when these piles are being driven at Berth 
4;
    <bullet> Vibratory driving/extraction of the 14-inch H piles at 
Berth 2: Isopleths for this vibratory driving encompass Castro Rocks, 
therefore is assumed that all of the 176 animals in the water could be 
exposed when this activity is being conducted at Berth 2; and
    <bullet> Vibratory removal of timber and concrete piles at Berths 
1, 2 and 4: Isopleths for this vibratory removal encompass Castro 
Rocks, therefore it is assumed that all of the estimated 176 animals in 
the water could be exposed during these activities.
    In order to account for other individuals that may be foraging in 
the more distant part of the Level B harassment zone, additional take 
of harbor seal has been estimated based on other harbor seal 
populations in the Central Bay. Using the same data set (Codde, S. and 
S. Allen. 2013, 2015, and 2017) that was used for Castro Rocks, a 
population for the Central Bay of 167 harbor seals was established 
based on other Central Bay haulouts at Alcatraz and Yerba Buena Island. 
The area of the Central Bay (bound by the Golden Gate, Richmond Bridge, 
SFOBB, and adjoining coastline) is approximately 134 km\2\, resulting 
in a harbor seal density of 1.25 animals per km\2\. The population that 
hauls out at Castro Rocks is not included in this density estimate 
because of the proximity of the haulout site to the project and 
potential take of those harbor seals has been estimated separately 
using the methods described above. The estimated take based on the 
Central Bay density is added to the take estimated for the Castro Rocks 
population, as provided in Table 9 below. Also provided in Table 9 is 
the estimated Level A take for impact driving of the steel 14-inch H 
piles, which has been estimated by taking Level B take and multiplying 
it by the ratio of the Level A zone area to the Level B zone area. 
Level A take is not requested for vibratory driving.

                                     Table 9--Daily Level A and Level B Harassment Estimate for Pacific Harbor Seal
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  Estimated Level B take per day
                                                                           Level A zone, ------------------------------------------------    Estimated
                        Pile type                          Level B zone        minus        Central bay                                    Level A take
                                                              (km\2\)     exclusion zone   \1\ (1.25 per      Project      Harbor seal--     per day--
                                                                              (km\2\)         km\2\)         vicinity          total           total
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                    Vibratory Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-inch steel H pile....................................          190.55              NA          238.39             176          414.39              NA
36-inch steel pile......................................          176.44              NA          220.55             176          396.55              NA
Timber/Concrete Pile Removal............................            7.14              NA            8.92             176          184.92              NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Impact Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-inch steel H pile....................................            1.36            0.10           * 1.7            * 44            45.7            3.36
24-inch concrete pile...................................            0.04               0            0.05            17.6           17.65               0
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Only displayed to provide the calculation of Level A take. Level B take authorized for vibratory driving would cover any Level B take from occasional
  impact driving.

    For impact pile driving of the 14-inch steel H piles, the PTS Zone 
is large enough to warrant a smaller exclusion zone and the 
authorization of some Level A harassment for harbor seal so that pile 
driving can be completed on schedule. A 35 meter shutdown zone (smaller 
than the Level A Zone) for this species would be established, but 
individuals that place themselves in the Level A zone but outside of 
the shut-down zone may experience Level A harassment, if they reside in 
that area for a long enough duration.

California Sea Lion

    The estimated California seal lion density of 0.16 animals per 
km\2\ previously described was used to calculate potential Level B 
exposures as shown in Table 10.

 Table 10--Daily Level B Harassment Exposure Estimate for California Sea
                                  Lion
------------------------------------------------------------------------
                                                           Level B take
                                                             estimate
                                                             (based on
                Pile type                  Level B zone     Central Bay
                                              (km\2\)       density of
                                                           0.16 animals
                                                            per km\2\ )
------------------------------------------------------------------------
                            Vibratory Driving
------------------------------------------------------------------------
14-inch steel H pile....................          190.55           30.48
36-inch steel pile......................          176.44           28.23

[[Page 27558]]

 
Timber/Concrete Pile Removal............            7.14            1.14
------------------------------------------------------------------------
                             Impact Driving
------------------------------------------------------------------------
14-inch steel H pile....................            * NA            * NA
24-inch concrete pile...................
0.04....................................
0.01....................................
------------------------------------------------------------------------
* Level B take authorized for vibratory driving would cover any Level B
  take from occasional impact driving.

Harbor Porpoise

    Based on monitoring conducted for the SFOBB project described 
previously, an in-water density of 0.17 animals per km\2\ was estimated 
by Caltrans for this species (NMFS 2017b). Using this in-water density 
and the areas of potential harassment, take is estimated for harbor 
porpoise as provided in Table 11. Also provided in Table 11 is the 
estimated Level A take for impact driving, which has been estimated by 
taking Level B take and multiplying it by the ratio of the Level A zone 
area to the Level B zone area. A single harbor porpoise could be 
exposed to Level A harassment during impact driving or 14-inch steel H-
piles as shown in Table 11. NMFS, however, conservatively proposes to 
authorize Level A take of four animals which is the average group size.

               Table 11--Daily Level A and Level B Harassment Estimate for Pacific Harbor Porpoise
----------------------------------------------------------------------------------------------------------------
                                                                                      Level B
                                                                   Level A zone,     estimate        Estimated
                    Pile type                      Level B zone        minus      Central Bay in-  Level A take
                                                      (km\2\)     exclusion zone    water--0.17       per day
                                                                      (km\2\)        per km\2\
----------------------------------------------------------------------------------------------------------------
                                                Vibratory Driving
----------------------------------------------------------------------------------------------------------------
14-inch steel H pile............................          190.55  ..............           32.39              NA
36-inch steel pile..............................          176.44  ..............           29.99              NA
Timber/Concrete Pile Removal....................            7.14  ..............            1.21              NA
----------------------------------------------------------------------------------------------------------------
                                                 Impact Driving
----------------------------------------------------------------------------------------------------------------
14-inch steel H pile............................            1.36          * 0.32          * 0.23            0.05
24-inch concrete pile...........................            0.04               0            0.01               0
----------------------------------------------------------------------------------------------------------------
* Only displayed to provide the calculation of Level A take. Level B take authorized for vibratory driving would
  cover any Level B take from occasional impact driving.

    For impact pile driving of the 14-inch H piles, the Level A Zone is 
large enough to warrant the authorization of some Level A. A 250 meter 
shutdown zone for this species would be established, but individuals 
that place themselves in the Level A zone but outside of the shut-down 
zone may experience Level A harassment, if they reside in that area for 
a long enough duration.

Northern Elephant Seal

    Monitoring of marine mammals in the vicinity of the SFOBB produced 
an estimated density for northern elephant seal of 0.06 animal per 
km\2\ (Caltrans, 2015b). Most sightings of northern elephant seal in 
San Francisco Bay occur in spring or early summer, and are less likely 
to occur during the periods of in-water work for this project. As a 
result, densities during pile driving for the planned action would be 
much lower. It is possible that a lone northern elephant seal may enter 
the Level B harassment area once per day during pile driving, for a 
total of 28 takes. Level A harassment of this species is not expected 
to occur and is not authorized by NMFS.

Northern Fur Seal

    As noted previously, the incidence of northern fur seal in San 
Francisco Bay depends largely on oceanic conditions, with animals more 
likely to strand during El Ni[ntilde]o events. The likelihood of El 
Ni[ntilde]o conditions occurring in 2018 is currently low, with La 
Ni[ntilde]a or neutral conditions expected to develop (NOAA, 2018). 
Given the low probability that fur seals would enter into the Bay and 
project area in 2018, Chevron has conservatively requested and NMFS has 
authorized10 fur seals takes by Level B harassment. Level A harassment 
of this species is not anticipated or authorized by NMFS.

Bottlenose Dolphin

    When this species is present in San Francisco Bay, it is more 
typically found close to the Golden Gate. Recently, beginning in 2015, 
two individuals have been observed frequently in the vicinity of Oyster 
Point (GGCR, 2016; GGCR 2017; Perlman, 2017). The average reported 
group size for bottlenose dolphins is five. Reports show that a group 
normally comes into San Francisco Bay near Yerba Buena Island once per 
week for approximately 2-week

[[Page 27559]]

stints and then leaves the Bay (NMFS, 2017b). Chevron assumed groups of 
five individuals may enter San Francisco Bay and the ensonified area 
three times during separate two-week spans. Therefore, groups of 5 
animals would potentially be exposed at a rate of once per week over 
six weeks, resulting in up to 30 Level B exposures. As such, NMFS 
authorizes the take by Level B harassment of 30 bottlenose dolphins. 
Although a small Level A zone for mid-frequency cetaceans is estimated 
during impact driving, marine mammal monitoring of the shutdown would 
ensure that take by Level A harassment does not occur.

Gray Whale

    Gray whales are the only whale species that travels far into San 
Francisco bay with any regularity. They occasionally enter the Bay 
during their northward migration period, and are most often sighted in 
the Bay between February and May. Most venture only about 2 to 3 km 
(about 1-2 mi) past the Golden Gate, but gray whales have occasionally 
been sighted as far north as San Pablo Bay. Pile driving is not 
anticipated to occur during the February through May timeframe and gray 
whales are not likely to be present at other times of year. In the very 
unlikely event that a gray whale or pair of gray whales makes its way 
close to the project area while pile driving activities are under way, 
Chevron has requested take by Level B harassment of up to two (2) gray 
whales per year. NMFS agrees and has authorized the take of 2 gray 
whales by Level B harassment. No Level A take is authorized.
    Tables 12 and 13 summarize the estimate of Level B and Level A 
harassment, respectively, for each species by pile driving activity for 
the 2018 construction season. For harbor seals, sea lions, harbor 
porpoise and elephant seals, the Level B harassment estimates are based 
on the number of individuals assumed to be exposed per day, the number 
of days of pile driving expected based on an average installation rate. 
The Level A harassment estimates are derived from the Level B 
harassment estimates by taking the Level B harassment total and 
multiplying it by the fractional ratio of the area of the Level A zone 
to the Level B zone.

                                      Table 12--Total Estimated Take by Level B Harassment by Species and Pile Type
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                             Species
                                                   Number of  Number of --------------------------------------------------------------------------------
           Pile type             Pile driver type    piles     driving     Harbor     CA sea     Harbor      Gray    N. elephant    N. fur    Bottlenose
                                                                 days       seal       lion     porpoise   whale *       seal       seal *    dolphin *
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-inch steel template pile **  Vibratory........          8          2      793.1      56.46      59.98         NA            2         NA           NA
Concrete pile removal.........  Vibratory........          5          1     184.92       1.14       1.21         NA            1         NA           NA
24-inch concrete..............  Impact...........          8          8      141.2       0.08       0.08         NA            8         NA           NA
14-inch H pile installation...  Impact/Vibratory.         36         12   4,972.68     365.76     388.68         NA           12         NA           NA
Timber pile removal...........  Vibratory........         53          5      924.6        5.7       6.05         NA            5         NA           NA
                                                  ------------------------------------------------------------------------------------------------------
    Total Take by Species       .................  .........  .........      7,017        429        456          2           28         10           30
     (2018).
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Take is not calculated by activity type for these species, only a total is given.
** Only the installation of the template piles will occur in 2018. Take associated with their removal will be requested in a subsequent IHA.
*** These piles will be preferentially driven with a vibratory driver, which would have a larger Level B zone than installation with an impact driver.
  Thus, Level B take for this species is based on installation using vibratory driver, and not an impact driver.


                                 Table 13--Authorized Take by Level A Harassment
----------------------------------------------------------------------------------------------------------------
                                                                     Number of                        Harbor
               Pile type                    Pile driver type       driving days     Harbor seal      porpoise
----------------------------------------------------------------------------------------------------------------
36-inch steel template pile...........  Vibratory...............               2               0               0
Concrete pile removal.................  Vibratory...............               1               0               0
24-inch concrete......................  Impact..................               8               0               0
14-inch H pile installation...........  Impact/Vibratory........              12              40             * 4
Timber pile removal...................  Vibratory...............               5               0               0
                                                                 -----------------------------------------------
    Total Take........................  ........................  ..............              40               4
----------------------------------------------------------------------------------------------------------------
* Harbor porpoise takes were increased to 4 to account for average group size.

    Table 14 provides a summary of authorized Level A and Level B takes 
as well as the percentage of a stock authorized for take.

                         Table 14--Authorized Take and Percentage of Stock or Population
----------------------------------------------------------------------------------------------------------------
                                                                    Authorized      Authorized        Percent
                Species                           Stock            Level A takes   Level B takes    population
----------------------------------------------------------------------------------------------------------------
Harbor seal...........................  California..............              40           6,977           22.6%
California sea lion...................  Eastern U.S.............  ..............             429           <0.01
Harbor porpoise.......................  San Francisco--Russian                 4             451             4.5
                                         River.
Northern elephant seal................  California Breeding.....  ..............              28           <0.01
Gray whale............................  Eastern North Pacific...  ..............               2           <0.01
Northern fur seal.....................  California..............  ..............              10           <0.01
Bottlenose Dolphin....................  California Coastal......  ..............              30             6.6
----------------------------------------------------------------------------------------------------------------


[[Page 27560]]

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 such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such 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 such 
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, we 
carefully consider 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, impact on 
operations.

Mitigation for Marine Mammals and Their Habitat

    The following measures would apply to Chevron's mitigation 
requirements:
    <bullet> Seasonal Restriction--To minimize impacts to listed fish 
species, pile-driving activities would occur between June 1 and 
November 30;
    <bullet> Daylight Construction Period--Work would occur only during 
daylight hours (7:00 a.m. to 7:00 p.m.) when visual marine mammal 
monitoring can be conducted;
    <bullet> Establishment of Shutdown Zone--For all pile driving and 
removal activities, Chevron will establish a shutdown zone. The purpose 
of a shutdown zone is generally to define an area within which shutdown 
of activity would occur upon sighting of a marine mammal (or in 
anticipation of an animal entering the defined area). A shutdown zone 
will be established which will include all or a portion of the area 
where underwater SPLs are expected to reach or exceed the cumulative 
SEL thresholds for Level A harassment as provided in Table 7. The 
shutdown isopleths for pinnipeds (harbor seals, California sea lion, 
Northern elephant seal, northern fur seal) and mid-frequency cetaceans 
(bottlenose dolphins) will be set at 15 meters during vibratory 
driving. A 30 meter shutdown zone during vibratory driving will be 
established for low-frequency cetaceans (gray whale) and high-frequency 
cetaceans (harbor porpoise). During impact driving the shutdown zones 
will be set at 250 meters for high-frequency cetaceans (harbor 
porpoise), 350 meters for low-frequency cetaceans (gray whales), and 35 
meters for pinnipeds (harbor seal, California sea lion, Northern 
elephant seal, northern fur seal) and mid-frequency cetaceans 
(bottlenose dolphin);
    <bullet> 10-Meter Shutdown Zone--During the in-water operation of 
heavy machinery (e.g., barge movements), a 10-m shutdown zone for all 
marine mammals will be implemented. If a marine mammal comes within 10 
m, operations shall cease and vessels shall reduce speed to the minimum 
level required to maintain steerage and safe working conditions;
    <bullet> Establishment of Monitoring Zones for Level A and Level 
B--Chevron will establish and monitor Level A harassment zones during 
impact driving for harbor seal extending to 183 meters and harbor seals 
and extending to 408 m for harbor porpoises. These are areas beyond the 
shutdown zone in which animals could be exposed to sound levels that 
could result in PTS. Chevron will also establish and monitor Level B 
harassment zones which are areas where SPLs are equal to or exceed the 
160 dB rms threshold for impact driving and the 120 dB rms threshold 
during vibratory driving and extraction. 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 
area outside the shutdown zone and thus prepare for a potential cease 
of activity should the animal enter the shutdown zone. The Level B 
zones are depicted in Table 11. As shown, the largest Level B zone is 
equal to 190.55 km\2\, making it impossible for Protected Species 
Observers (PSOs) to view the entire harassment area. Due to this, Level 
B exposures will be recorded and extrapolated based upon the number of 
observed take and the percentage of the Level B zone that was not 
visible;
    <bullet> Soft Start--The use of a soft-start procedure are believed 
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. Chevron shall use soft start 
techniques when impact pile driving. Soft start requires contractors to 
provide an initial set of strikes at reduced energy, followed by a 
thirty-second waiting period, then two subsequent reduced energy strike 
sets;
    <bullet> Pile Caps/Cushions--Chevron will employ the use of pile 
caps or cushions as sound attenuation devices to reduce impacts from 
sound exposure during impact pile driving;
    <bullet> Pre-Activity Monitoring--Pre-activity monitoring shall 
take place from 30 minutes prior to initiation of pile driving activity 
and post-activity monitoring shall continue through 30 minutes post-
completion of pile driving activity. Pile driving may commence at the 
end of the 30-minute pre-activity monitoring period, provided observers 
have determined that the shutdown zone is clear of marine mammals, 
which includes delaying start of pile driving activities if a marine 
mammal is sighted in the zone, as described below;
    <bullet> If a marine mammal approaches or enters the shutdown zone 
during activities or pre-activity monitoring, all pile driving 
activities at that location shall be halted or delayed, respectively. 
If pile driving is halted or delayed due to the presence of a marine 
mammal, the activity may not resume or commence until either the animal 
has voluntarily left and been visually confirmed beyond the shutdown 
zone and 15 minutes have passed without re-detection of the animal. 
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 thirty minutes; and
    <bullet> Non-authorized Take Prohibited--If a species for which 
authorization has not been granted or a species for which authorization 
has been granted but the authorized takes are met, is observed 
approaching or within the monitoring zone, pile driving and removal 
activities must shut down immediately using delay and shut-down 
procedures. Activities must not resume until the animal has been 
confirmed to have left

[[Page 27561]]

the area or an observation time period of 15 minutes has elapsed.
    Based on our evaluation of the applicant's planned measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
required mitigation measures provide the means effecting the least 
practicable impact on the affected species or stocks and their habitat, 
paying particular attention to rookeries, mating grounds, and areas of 
similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, Section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
action area. 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:

    <bullet> Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
    <bullet> 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);
    <bullet> Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
    <bullet> How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
    <bullet> Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
    <bullet> Mitigation and monitoring effectiveness.

Visual Monitoring

    The following visual monitoring measures are required as part of 
the issued IHA.
    <bullet> One day of biological monitoring would occur within one 
week before the project's start date to establish baseline 
observations;
    <bullet> Monitoring distances, in accordance with the identified 
shutdown, Level A, and Level B zones, will be determined by using a 
range finder, scope, hand-held global positioning system (GPS) device 
or landmarks with known distances from the monitoring positions;
    <bullet> Monitoring locations will be established at locations 
offering best views of the monitoring zone;
    <bullet> Monitoring will be continuous unless the contractor takes 
a break longer than 2 hours from active pile driving, in which case, 
monitoring will be required 30 minutes prior to restarting pile 
installation;
    <bullet> For in-water pile driving, under conditions of fog or poor 
visibility that might obscure the presence of a marine mammal within 
the shutdown zone, the pile in progress will be completed and then pile 
driving suspended until visibility conditions improve;
    <bullet> At least two PSOs will be actively scanning the monitoring 
zone during all pile driving activities;
    <bullet> Monitoring of pile driving shall be conducted by qualified 
PSOs (see below), who shall have no other assigned tasks during 
monitoring periods. Chevron shall adhere to the following conditions 
when selecting observers:
    (1) Independent PSOs shall be used (i.e., not construction 
personnel);
    (2) At least one PSO must have prior experience working as a marine 
mammal observer during construction activities;
    (3) Other PSOs may substitute education (degree in biological 
science or related field) or training for experience; and
    (4) Chevron shall submit PSO CVs for approval by NMFS;
    <bullet> Chevron will ensure that observers have the following 
additional qualifications:
    (1) Ability to conduct field observations and collect data 
according to assigned protocols;
    (2) Experience or training in the field identification of marine 
mammals, including the identification of behaviors;
    (3) Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    (4) 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
    (5) 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.
    A draft marine mammal monitoring report would be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities. It will include an overall description of work completed, a 
narrative regarding marine mammal sightings, and associated marine 
mammal observation data sheets. Specifically, the report must include:

    <bullet> Date and time that monitored activity begins or ends;
    <bullet> Construction activities occurring during each observation 
period;
    <bullet> Deviation from initial proposal in pile numbers, pile 
types, average driving times, etc.
    <bullet> Weather parameters (e.g., percent cover, visibility);
    <bullet> Water conditions (e.g., sea state, tide state);
    <bullet> For each marine mammal sighting the following must be 
recorded:
    (1) Species, numbers, and, if possible, sex and age class of marine 
mammals;
    (2) Description of any observable marine mammal behavior patterns, 
including bearing and direction of travel and distance from pile 
driving activity;
    (3) Location and distance from pile driving activities to marine 
mammals and distance from the marine mammals to the observation point; 
and
    (4) Estimated amount of time that the animals remained in the Level 
B zone.
    <bullet> Description of implementation of mitigation measures 
within each monitoring period (e.g., shutdown or delay);
    <bullet> Other human activity in the area.
    <bullet> A summary of the following must be included in the report.
    (1) Total number of individuals of each species detected within the 
Level A and Level B Zones, and estimated take extrapolated across 
entire Level B zone; and
    (2) Daily average number of individuals of each species

[[Page 27562]]

(differentiated by month as appropriate) detected within the Level B 
Zone, and estimated take extrapolated across entire Level B zone.
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA 
(if issued), such as an injury, serious injury or mortality, Chevron 
would immediately cease the specified activities and report the 
incident to the Chief of the Permits and Conservation Division, Office 
of Protected Resources, NMFS, and the West Coast Regional Stranding 
Coordinator. The report would include the following information:
    <bullet> Description of the incident;
    <bullet> Environmental conditions (e.g., Beaufort sea state, 
visibility);
    <bullet> Description of all marine mammal observations in the 24 
hours preceding the incident;
    <bullet> Species identification or description of the animal(s) 
involved;
    <bullet> Fate of the animal(s); and
    <bullet> Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with Chevron to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Chevron would not be able 
to resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that Chevron discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (e.g., in less than 
a moderate state of decomposition as described in the next paragraph), 
Chevron would immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
and the West Coast Regional Stranding Coordinator. The report would 
include the same information identified in the paragraph above. 
Activities would be able to continue while NMFS reviews the 
circumstances of the incident. NMFS would work with Chevron to 
determine whether modifications in the activities are appropriate.
    In the event that Chevron discovers an injured or dead marine 
mammal and the lead PSO determines that the injury or death is not 
associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), Chevron would report the incident 
to the Chief of the Permits and Conservation Division, Office of 
Protected Resources, NMFS, and the West Coast Regional Stranding 
Coordinator within 24 hours of the discovery. Chevron would provide 
photographs or video footage (if available) or other documentation of 
the stranded animal sighting to NMFS and the Marine Mammal Stranding 
Network.

Hydroacoustic Monitoring

    Sound Source Verification (SSV) testing of would be conducted under 
this IHA. The purpose of the planned acoustic monitoring plan is to 
collect underwater sound-level information at both near and distant 
locations during vibratory pile extraction and installation and impact 
pile installation. The plan provides a protocol for hydroacoustic 
measurements during pile driving operations. Acoustic monitoring would 
be conducted on a minimum of two of each pile type. Since little data 
exist for source levels associated with installation of 24-inch square 
concrete piles (including data on single strike sound exposure level 
metrics) Chevron would conduct in-situ measurements during installation 
of eight piles. The SSV testing would be conducted by an acoustical 
firm with prior experience conducting SSV testing. Final results would 
be sent to NMFS. Findings may be used to establish Level A and Level B 
isopleths during impact and vibratory driving. Any alterations to the 
shutdown or harassment zones based on testing data must be approved by 
NMFS. The Hydroacoustic Monitoring Plan is contained on the following 
NMFS website: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities.

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 responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), 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's 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 environmental 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).
    Pile driving and extraction associated with Chevron's WMEP project 
as outlined previously have the potential to injure, disturb or 
displace marine mammals. Specifically, the specified activities may 
result in Level B harassment (behavioral disturbance) for seven marine 
mammal species authorized for take from underwater sound generated 
during pile driving operations. Level A harassment in the form of PTS 
may also occur to limited numbers of two species. No serious injuries 
or mortalities are anticipated to occur as a result of Chevron's pile 
driving activities.
    A limited number of animals (40 harbor seals and 4 harbor 
porpoises) could experience Level A harassment in the form of PTS if 
they stay within the Level A harassment zone during impact driving of 
24-inch steel H-piles. Installation of these piles would occur over 
eight days and impact driving will not be the primary method of 
installation. The piles will mainly be installed using only vibratory 
driving. Impact driving will be used only if the vibrated pile 
encounters an obstruction such as an old sunken pile. It is unlikely 
that this would occur for all four piles projected to be installed each 
driving day. An assumption of four piles per day was used to calculate 
Level A zone sizes. If four piles did require impact installation on a 
single day it is unlikely that the same individual marine mammal would 
be within the relatively small Level A zone during the installation of 
every pile. In most instances impact driving will not be required at 
all. Furthermore, the degree of injury is expected to be mild and is 
not likely to affect the reproduction or

[[Page 27563]]

survival of the individual animals. It is expected that, if hearing 
impairments occurs, most likely the affected animal would lose a few dB 
in its hearing sensitivity, which in most cases is not likely to affect 
its survival and recruitment.
    The Level B takes that are anticipated and authorized are expected 
to be limited to short-term behavioral harassment. Marine mammals 
present near the action area and taken by Level B harassment would most 
likely show overt brief disturbance (e.g., startle reaction) and 
avoidance of the area from elevated noise level during pile driving. 
Repeated exposures of individuals to levels of sound that may cause 
Level B harassment are unlikely to significantly disrupt foraging 
behavior. Thus, even repeated Level B harassment of some small subset 
of the overall stock is unlikely to result in any significant realized 
decrease in fitness for the affected individuals, and thus would not 
result in any adverse impact to the stock as a whole.
    The project is not expected to have significant adverse effects on 
affected marine mammal habitat. The activities may cause fish to leave 
the area temporarily. This could impact 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 affected habitat, the impacts to marine mammal habitat are not 
expected to cause significant or long-term negative consequences.
    The likelihood that marine mammals will be detected by trained 
observers is high under the environmental conditions described for the 
project. The employment of the soft-start mitigation measure would also 
allow marine mammals in or near the shutdown and Level A zone zones to 
move away from the impact driving sound source. Therefore, the 
mitigation and monitoring measures are expected to reduce the potential 
for injury and reduce the amount and intensity of behavioral 
harassment. Furthermore, the pile driving activities analyzed here are 
similar to, or less impactful than, numerous construction activities 
conducted in similar locations which have taken place with no reported 
injuries or mortality to marine mammals, and no known long-term adverse 
consequences from behavioral harassment.
    In summary and as described above, the following factors primarily 
support our determination that the impacts resulting from this activity 
are not expected to adversely affect the species or stock through 
effects on annual rates of recruitment or survival:
    <bullet> No mortality is anticipated or authorized;
    <bullet> Anticipated incidences of Level A harassment would be in 
the form of a small degree of PTS to a limited number of animals;
    <bullet> Anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior;
    <bullet> The relatively short and intermittent duration of in-water 
construction activities;
    <bullet> The small percentage of the stock that may be affected by 
project activities (<22.8 percent for all stocks); and
    <bullet> Efficacy of mitigation measures is expected to minimize 
the likelihood and severity of the level of harassment.
    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 required monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the planned activity will have a negligible impact on all affected 
marine mammal stocks or species.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Section 101(a)(5)(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. Additionally, other qualitative factors may 
be considered in the analysis, such as the temporal or spatial scale of 
the activities.
    Table 14 depicts the number of animals that could be exposed to 
Level A and Level B harassment from work associated with Chevron's 
project. The analysis provided indicates that authorized takes account 
for no more than 22.6 percent of the populations of the stocks that 
could be affected. These are small numbers of marine mammals relative 
to the sizes of the affected stocks.
    Based on the analysis contained herein of the planned (including 
the required mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS finds that small numbers of marine mammals 
will 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 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations with 
no anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
IHA qualifies to be categorically excluded from further NEPA review.

Endangered Species Act (ESA)

    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.
    No incidental take of ESA-listed species is authorized or expected 
to result from this activity. Therefore, NMFS has determined that 
formal consultation under section 7 of the ESA is not required for this 
action.

Authorization

    NMFS has issued an IHA to Chevron to take seven species of marine 
mammal incidental to pile driving and removal activities at Chevron's 
Long Wharf from June 1, 2018 through May 31, 2019 provided the 
previously mentioned

[[Page 27564]]

mitigation, monitoring, and reporting requirements are incorporated.

    Dated: June 7, 2018.
Elaine T. Saiz,
Acting Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2018-12629 Filed 6-12-18; 8:45 am]
 BILLING CODE 3510-22-P