[Federal Register Volume 84, Number 81 (Friday, April 26, 2019)]
[Notices]
[Pages 17788-17804]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-08415]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XG876


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; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from Chevron for authorization to 
take marine mammals incidental to pile driving and removal associated 
with the Long Wharf Maintenance and Efficiency Project (LWMEP) in San 
Francisco Bay, California. Pursuant to the Marine Mammal Protection Act 
(MMPA), NMFS is requesting comments on its proposal to issue an 
incidental harassment authorization (IHA) to incidentally take marine 
mammals during the specified activities. NMFS is also requesting 
comments on a possible one-year renewal that could be issued under 
certain circumstances and if all requirements are met, as described in 
Request for Public Comments at the end of this notice. NMFS will 
consider public comments prior to making any final decision on the 
issuance of the requested MMPA authorizations and agency responses will 
be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than May 28, 
2019.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Physical comments should be sent to 
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments 
should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted online at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying 
information (e.g., name, address) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit confidential 
business information or otherwise sensitive or protected information.

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: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these 
documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

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

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 preliminarily determined that the 
issuance of the proposed IHA qualifies to be categorically excluded 
from further NEPA review.
    We will review all comments submitted in response to this notice 
prior to concluding our NEPA process or making a final decision on the 
IHA request.

Summary of Request

    On January 17, 2019, NMFS received a request from Chevron for an 
IHA to take marine mammals incidental to pile

[[Page 17789]]

driving and pile removal associated with the LWMEP in San Francisco 
Bay, California. The application was deemed adequate and complete on 
April 8, 2019. Chevron's request is for take of a small number of seven 
species of marine mammals, by Level B harassment and Level A 
harassment. Neither Chevron nor NMFS expects serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.
    NMFS previously issued an IHA to Chevron for similar work (82 FR 
27240; June 17, 2017). However, the construction schedule and scope was 
revised and no work was conducted under that IHA. NMFS issued a second 
IHA on May 31, 2018 to Chevron for work not conducted in 2017 (83 FR 
27578; June 13, 2018). This newly proposed IHA would cover one year of 
this larger project for which Chevron obtained the prior IHAs, and 
Chevron also intends to request take authorizations for subsequent 
facets of the project. The larger multi-year project involves various 
construction activities that would allow Chevron to comply with Marine 
Oil Terminal Engineering and Maintenance Standards (MOTEMS) and to 
improve safety and efficiency at the Long Wharf. Chevron complied with 
all the requirements (e.g., mitigation, monitoring, and reporting) of 
the previous IHA and information regarding their monitoring results may 
be found in the Estimated Take section.
    Because of the similarity of the work and marine mammal impacts to 
that covered in previous IHAs, we have often cited back to previous 
documents for more detailed descriptions.

Description of Proposed Activity

Overview

    Chevron's Richmond Refinery Long Wharf (Long Wharf) located in San 
Francisco Bay, is the largest marine oil terminal in California. 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 MOTEMS requirements. The 
purpose of the proposed LWMEP is to comply with current MOTEMS 
requirements and to improve safety and efficiency at the Long Wharf.
    Impact and vibratory pile driving and removal will be employed 
during the proposed construction project. These actions could produce 
underwater sound at levels that could result in the injury or 
behavioral harassment of marine mammal species. The proposed IHA would 
be effective from June 1, 2019 through May 31, 2020.

Dates and Duration

    Pile driving activities would be timed to occur within the standard 
NMFS work windows for Endangered Species Act (ESA)-listed fish species 
(June 1 through November 30) over multiple years. An estimated 67 days 
of pile driving activity within the designated work window are planned 
for 2019. Additional work in the future will require subsequent IHAs. 
The proposed IHA would be effective from June 1, 2019 through May 31, 
2020.

Specific Geographic Region

    The Long Wharf is located in San Francisco Bay (the Bay) just south 
of the eastern terminus of the Richmond-San Rafael Bridge (RSRB) in 
Contra Costa County. The wharf is located in the northern portion of 
the central bay, which is generally defined as the area between the 
RSRB, Golden Gate Bridge, and San Francisco-Oakland Bay Bridge (SFOBB).
BILLING CODE 3510-22-P

[[Page 17790]]

[GRAPHIC] [TIFF OMITTED] TN26AP19.000

BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The proposed project would involve modifications at Berths 1, 2, 3, 
and 4 as shown in Figure 1. NMFS refers the reader to the documents 
related to the previously issued 2018 IHA for more detailed description 
of the project activities, which include vibratory

[[Page 17791]]

driving and removal as well as impact pile driving. These previous 
documents include the Federal Register notice of the issuance of the 
2018 IHA for Chevron's LWMEP project (83 FR 27578; June 13, 2018), the 
Federal Register notice of the proposed IHA (83 FR 18802; April 30, 
2018), as well as Chevron's current IHA application for the 2019 work 
season. The current application is requesting take for the pile driving 
that will occur during the 2019 work season as shown in Table 1.

                               Table 1--Pile Driving Summary for 2019 Work Season
----------------------------------------------------------------------------------------------------------------
                                                                                     Number of       Number of
                   Pile type                            Pile driver type               piles       driving days
----------------------------------------------------------------------------------------------------------------
60-inch steel pipe piles......................  Impact..........................               8               8
36-inch steel template pile (Installation and   Vibratory/Impact Proofing.......               8               4
 removal).
20-inch steel template pile (Installation and   Vibratory.......................               8               4
 removal).
22-inch concrete pile removal.................  Vibratory.......................               5               1
24-inch square concrete.......................  Impact..........................              39              30
12-inch composite barrier piles...............  Vibratory.......................              52              11
Timber pile removal...........................  Vibratory.......................             106               9
----------------------------------------------------------------------------------------------------------------

    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Table 2 lists species that may occur in the vicinity of the project 
area. A description of the marine mammals in the area of the activities 
is found in the Federal Register notice of the issuance of the 2018 IHA 
for Chevron's LWMEP project (83 FR 27578; June 13, 2018), the Federal 
Register notice of the proposed IHA (83 FR 18802; April 30, 2018), as 
well as Chevron's current IHA application for the 2019 work season.. 
NMFS has reviewed the monitoring data from the initial IHA, recent 
draft Stock Assessment Reports, information on relevant Unusual 
Mortality Events, and other scientific literature, and determined that 
neither this nor any other new information affects which species or 
stocks have the potential to be affected or the pertinent information 
in the Description of the Marine Mammals in the Area of Specified 
Activities contained in the supporting documents for the initial IHA. 
Specifically, the only change from the 2018 IHA is an increase in 
numbers of the eastern north Pacific stock of gray whale which have 
increased 20,990 to 26,960.

                                     Table 2--Marine Mammals Potentially Present in the Vicinity of the Project Area
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                                                                                         ESA/MMPA status;    Stock abundance (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
    Gray whale......................  Eschrichtius robustus..  Eastern North Pacific..  -/-; (N)            26,960 (0.05, 25,849,         801        138
                                                                                                             2016).
Family Delphinidae:
    Bottlenose dolphin..............  Tursiops truncatus.....  California Coastal.....  -/-; (N)            453 (0.06, 346, 2011).        2.7      >=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).
    Steller sea lion................  Eumetopias jubatus.....  Eastern U.S. stock.....  -/-; (N)            41,638 (-, 41,638,          2,498        108
                                                                                                             2015).
    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 angustirostris  California Breeding      -/-; (N)            179,000 (-, 81,368,         4,882        8.8
                                                                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: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region#reports. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.


[[Page 17792]]

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 3.

                  Table 3--Marine Mammal Hearing Groups
                              [NMFS, 2018]
------------------------------------------------------------------------
            Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen   7 Hz to 35 kHz.
 whales).
Mid-frequency (MF) cetaceans           150 Hz to 160 kHz.
 (dolphins, toothed whales, beaked
 whales, bottlenose whales).
High-frequency (HF) cetaceans (true    275 Hz to 160 kHz.
 porpoises, Kogia, river dolphins,
 cephalorhynchid, Lagenorhynchus
 cruciger & L. australis).
Phocid pinnipeds (PW) (underwater)     50 Hz to 86 kHz.
 (true seals).
Otariid pinnipeds (OW) (underwater)    60 Hz to 39 kHz.
 (sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Seven marine mammal species (three cetacean and four pinniped (two 
otariid and two phocid) species) have the reasonable potential to co-
occur with the proposed survey activities. Of the cetacean species that 
may be present, one is classified as a low-frequency cetacean (i.e., 
gray whale), one is classified as a mid-frequency cetacean (i.e., 
bottlenose dolphin), and one is classified as a high-frequency cetacean 
(i.e., harbor porpoise).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    A description of the potential effects of the specified activities 
on marine mammals and their habitat may be found in the Federal 
Register notice of the issuance of the 2018 IHA for Chevron's LWMEP 
project (83 FR 27578; June 13, 2018) and the Federal Register notice of 
the proposed IHA (83 FR 18802; April 30, 2018). This information 
remains applicable to the issuance of the proposed 2019 IHA. NMFS has 
reviewed the monitoring data from the initial IHA and other scientific 
literature, and found no new information that would affect our initial 
analysis of impacts on marine mammals and their habitat.
    The Estimated Take by Incidental Harassment section later in this 
document includes a quantitative analysis of the number of individuals 
that are expected to be taken by this activity. The Negligible Impact 
Analysis and Determination section considers the content of this 
section, the Estimated Take by Incidental Harassment section, and the 
Proposed Mitigation section, to draw conclusions regarding the likely 
impacts of these activities on the reproductive success or survivorship 
of individuals and how those impacts on individuals are likely to 
impact marine mammal species or stocks.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
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 (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 limited auditory injury (Level A 
harassment) to result, primarily for high frequency species (harbor 
porpoises) because predicted auditory injury zones are larger than for 
other functional hearing groups and for phocids (harbor seals) as there 
is a sizable harbor seal haulout (Castro Rocks) located in close 
proximity to the project area. The proposed 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 proposed to 
be authorized for this activity. Below we describe how the take is 
estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent

[[Page 17793]]

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. We note that while these basic factors 
can contribute to a basic calculation to provide an initial prediction 
of takes, additional information that can qualitatively inform take 
estimates is also sometimes available (e.g., previous monitoring 
results or average group size). Below, we describe the factors 
considered here in more detail and present the proposed take 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). 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 dB re 1 microPascal, 
root mean square ([mu]Pa (rms) for continuous (e.g., vibratory pile-
driving), and above 160 dB re 1 [mu]Pa (rms) for non-explosive 
impulsive (e.g., seismic airguns) or intermittent (e.g., scientific 
sonar) sources.
    Chevron's proposed activity includes the use of continuous 
(vibratory pile driving and removal) and intermittent (impact pile 
driving) sources and, therefore, the 120 and 160 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 (Version 2.0) (NMFS, 2018) identifies dual criteria to 
assess auditory injury (Level A harassment) to five different marine 
mammal groups (based on hearing sensitivity) as a result of exposure to 
noise from two different types of sources (impulsive or non-impulsive). 
Chevron's proposed activity includes the use of impulsive (impact pile 
driving) and non-impulsive (vibratory pile driving and removal) 
sources.
    These thresholds are provided in Table 4 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                    PTS onset acoustic thresholds \*\ (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE, HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]Pa\2\s. In this Table, thresholds are abbreviated to reflect American National
  Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as incorporating
  frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript ``flat'' is
  being included to indicate peak sound pressure should be flat weighted or unweighted within the generalized
  hearing range. The subscript associated with cumulative sound exposure level thresholds indicates the
  designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds) and
  that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could be
  exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible, it
  is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.

Source Levels

    The project includes impact pile driving, vibratory pile driving 
and vibratory pile removal. Source levels of pile driving activities 
are based on hydroacoustic testing performed in 2018 at the LWMEP 
location as well as reviews of measurements of the same or similar 
types and dimensions of piles available in the literature. Based on 
this information, the source levels described below are assumed for the 
underwater noise produced by construction activities.
    Eight batter steel pipe piles, 60-inch diameter would be installed 
adjacent to the existing Wharf structure to retrofit the Berth 4 
loading platform to limit displacement in a seismic event. An impact 
driver will be used to install these piles, as it is difficult to 
vibrate in batter piles and these piles have very high axial design 
loads that can only be achieved by impact driving methods.
    Other projects conducted under similar circumstances were reviewed 
in order to estimate the approximate noise effects of the 60-inch steel 
piles. The best match found for sound source levels is from summary 
values provided by Caltrans in their hydroacoustic guidance document 
(Caltrans 2015). Summary values for the impact pile driving of 60-inch 
steel pipe piles indicates that noise levels of up to 210 peak, 185 dB 
SEL (single strike), and 195 RMS would be produced at 10

[[Page 17794]]

meters during pile driving using no sound attenuation such as a bubble 
curtain. The use of properly functioning bubble curtains is expected to 
reduce the peak and RMS noise levels by about 7 dB. As a result, noise 
levels of 203 dB peak, 178 dB SEL (single strike), and 188 dB are 
utilized to assess potential acoustic impacts.
    It is expected that just one 60-inch pile would be driven over one 
(1) hour of active driving in a given day and that only one (1) pile 
would be installed in a given week. Installation could require up to 
2,400 blows from an impact hammer, such as a HHK-16 or similar diesel 
hammer, producing approximately 173,000 to 217,000 ft. lbs. maximum 
energy per blow and 1.5 to 2 sec/blow average. As noted above, bubble 
curtains will be used during the installation of the 60-inch steel pipe 
piles in order to reduce underwater noise levels, with an assumed 
attenuation of 7 dB. NMFS acknowledges that noise level reductions 
measured at different project locations as well as different received 
ranges can vary widely. However, NMFS believes it reasonable to use a 
source level reduction factor for sound attenuation device 
implementation during impact pile driving. NMFS reviewed Caltrans' 
bubble curtain ``on and off'' studies conducted in San Francisco Bay in 
2003 and 2004. Based on near distance measurements (a total of 28 
measurements, with 14 during bubble curtain on and 14 during bubble 
curtain off), the linear averaged noise level reduction is 7 dB. As a 
conservative approach, NMFS will use a standard reduction of 7 dB of 
the source level for impact zone estimates.
    Installation of 24-inch diameter square concrete piles is proposed 
for the modifications at the four berths. Approximately one to two of 
these piles would be installed in one work day, using impact driving 
methods and a bubble curtain attenuation system. 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 from a DelMag D62 22 or similar diesel hammer, producing 
approximately 165,000 ft lbs maximum energy (may not need full energy) 
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 
(2) piles are installed.
    To estimate the noise effects of the 24-inch square concrete piles, 
the underwater noise measurements recorded for this pile type at the 
Long Wharf during the 2018 construction season are utilized. These 
measured values were: 191 dB peak, 161 dB SEL (single strike), and 173 
dB RMS during attenuated impact driving (AECOM 2018).
    As part of the Berth 4 Loading Platform seismic retrofit, four (4) 
clusters of 13 composite piles (52 piles total) will be installed to 
provide protection to the infrastructure. These plastic encased 
concrete piles would be installed with a vibratory pile driver (APE 
400B King Kong or similar vibratory driver), with a drive time of 
approximately 10 minutes per pile. Up to five (5) of these piles could 
be installed in any single work day.
    Projects conducted under similar circumstances with similar piles 
were reviewed in order to approximate the noise effects of the 12-inch 
composite barrier piles. Since these piles will be composed of concrete 
encased in plastic, vibratory installation of similarly sized concrete 
piles would provide a good surrogate. However, concrete piles are 
rarely installed with a vibratory driver, and no suitable data could be 
located. In the absence of this data, we are conservatively using data 
from the Anacortes Ferry Terminal in Washington State, where 13-inch 
plastic coated steel piles were installed with a vibratory hammer. RMS 
noise levels produced during this installation varied from 138 to 158 
dB RMS at 43 meters (141 feet) from the pile (Laughlin 2012). From 
these measurements, a peak noise value of 178 dB and an average RMS 
value of 168 dB normalized to a 10 meter (33 feet) distance was used to 
estimate the extent of underwater noise from installation of the 12-
inch composite piles. During installation of the 12-inch composite 
barrier piles for the proposed Project, up to 50 minutes of vibratory 
driving could occur per day.
    For the Berth 4 Loading Platform seismic retrofit, eight (8) 36-
inch diameter temporary steel piles would be installed using a 
vibratory pile driver (APE 400B King Kong or similar vibratory driver) 
will be needed to support the guide template for the driving of the 
permanent 60-inch steel pipe piles. Each 36-inch temporary pile has an 
estimated drive time of approximately 10 minutes per pile. Up to four 
(4) of these piles could be installed in any single work day.
    Projects conducted under similar circumstances with similar piles 
were reviewed in order to approximate the noise effects of the 36-inch 
steel pipe. The best match for estimated noise levels is from the 
Explosive Handling Wharf-2 (EHW-2) project located at the Naval Base 
Kitsap in Bangor, Washington (Illingworth and Rodkin 2013) During 
vibratory pile driving associated with this Project, which occurred 
under similar circumstances, average peak noise levels were 
approximately 180 dB, and the RMS was approximately 170 dB at a 10 
meter (33 feet) distance (Caltrans 2015a). Installation of the 36-inch 
steel pipe piles is expected to be require 40 minutes per day.
    In total, two of the eight 36-inch temporary piles will require 
proofing using an impact hammer. Each pile will require up to 30 
strikes from an impact hammer during proofing which will take place 
during the last foot of pile driving. Up to two (2) piles would be 
proofed in one day, with each pile requiring up to 30 strikes from an 
impact hammer, for a total of 60 strikes in one day. The best match 
found for sound source levels is from summary values provided by 
Caltrans in their hydroacoustic guidance document (Caltrans 2015). 
Summary values for the impact pile driving of 36-inch steel pipe piles 
in water less than 5m deep indicates that noise levels of up to 210 
peak, 180 dB SEL (single strike), and 193 RMS would be produced at 10 
meters during pile driving. Since impact hammers are often operated at 
reduced power output during proofing, the source levels are likely to 
be lower than the values for impact driving used here. Due to very 
limited time that pile proofing would occur (60 strikes total, over a 
few minutes of active hammering) no sound attenuation would be used.
    The Berth 4 Loading Platform seismic retrofit will require 
vibratory installation of, eight (8) 20-inch diameter temporary steel 
piles (APE 400B King Kong or similar vibratory driver) to support the 
guide template needed for the driving the permanent 60-inch steel pipe 
piles. Each 20-inch temporary pile has a drive time per pile of 
approximately 10 minutes. Up to four (4) of these piles could be 
installed in any single work day. The best match for estimated noise 
levels is from vibratory driving of 24-inch piles at the Explosive 
Handling Wharf-2 (EHW-2) project located at the Naval Base Kitsap in 
Bangor, Washington (Illingworth and Rodkin 2013). During vibratory pile 
driving associated with this Project, which occurred under similar 
circumstances, measured peak noise levels were approximately 180 dB, 
and the RMS was approximately 163 dB at a 10 meter (33 feet) distance 
(Illingworth and Rodkin 2013). During installation of the 20-inch steel 
pipe piles will require approximately 40 minutes per day.
    The project includes the removal of 106 16-inch timber piles, and 
five (5) 18

[[Page 17795]]

to 24-inch square concrete piles using a vibratory pile driver. Up to 
12 of these piles could be extracted in one (1) work day. Extraction 
time needed for each pile may vary greatly, but could require 
approximately 400 seconds (approximately seven (7) minutes) from an APE 
400B King Kong or similar driver. The most applicable noise values for 
wooden pile removal from which to base estimates for the LWMEP are 
derived from measurements taken at the Pier 62/63 pile removal in 
Seattle, Washington. During vibratory pile extraction associated with 
this Project, which occurred under similar circumstances, the RMS was 
approximately 152 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.
    For pile driving that does not have project specific hydroacoustic 
data available, the practical spreading model with a transmission loss 
coefficient of 15 (4.5 dB per doubling of distance) is used. However, 
project-specific transmission loss values have been measured for the 
impact driving of concrete piles and the vibratory driving of concrete 
piles. For those types of pile driving, a transmission loss factor of 
20 (~8 dB per doubling of distance) has been measured and will be 
applied. This value is calculated from hydroacoustic monitoring of 
vibratory driving of steel piles and attenuated impact driving of 
concrete piles conducted as part of the LWMEP. The results of the 2018 
hydroacoustic monitoring are provided in Appendix A of the application.
    When the 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, we 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 may result in some degree of 
overestimate of Level A harassment 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 (such as impact 
and vibratory pile driving), 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 in 
Table 5.

                                                                              Table 5--Inputs for User Spreadsheet
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
       Spreadsheet tab used                             E.1-2: Impact pile driving                                                       A.1: Vibratory driving
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
            Pile type                  60-inch steel         24-inch concrete        36-inch steel        12-inch Composite        36-inch steel          20-inch steel        Wood/ concrete
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Source Level.....................  178 SEL..............  161 SEL..............  180 SEL..............  168 RMS..............  170 RMS..............  150 RMS.............  152 RMS.
Weighting Factor Adjustment (kHz)  2....................  2....................  2....................  2.5..................  2.5..................  2.5.................  2.5.
Number of strikes in 1 h OR        2,400................  300..................  30...................  NA...................  NA...................  NA..................  NA.
 number of strikes per pile.
Number of piles per day..........  1....................  2....................  2....................  5....................  4....................  4...................  12.
Propagation (xLogR)..............  15...................  20...................  15...................  15...................  20...................  20..................  15.
Duration to Drive single pile      NA...................  NA...................  NA...................  10...................  10...................  10..................  7.
 (minutes).
Distance of source level           10...................  10...................  10...................  10...................  10...................  10..................  10.
 measurement (meters).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    Table 6 shows the Level A harassment isopleths as determined 
utilizing inputs from Table 5. Note that for all calculations, the 
results based on SELss are larger than SPLpk, 
therefore, distances calculated using SELss are used to 
calculate the area. Level B Harassment isopleths for impact and 
vibratory driving and extraction are shown in Table 7.

                              Table 6--Radial Distances to Level A Harassment Isopleths During Impact and Vibratory Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               Source levels at 10 meters  (dB)                  Distance to Level A threshold in meters  (feet)
                                     -------------------------------------------------------------------------------------------------------------------
   Project element requiring pile                                                            Low-         Mid-        High-
            installation                        Peak                    RMS/SEL           frequency    frequency    frequency      Phocid      Otariid
                                                                                          cetaceans    cetaceans    cetaceans    pinnipeds    pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Attenuated Impact Driving (with
 bubble curtain):
    60-inch steel pipe (1 per day)..  203.....................  178 SEL................  831 (2,726)      30 (97)  990 (3,247)  445 (1,459)     32 (106)
    24-inch square concrete (1-2 per  191.....................  161 SEL................      19 (64)        2 (5)      22 (73)      12 (40)        2 (6)
     day).
Impact Pile Proofing (no bubble
 curtain):
    36-inch steel pipe pile (2        210.....................  180 SEL................     97 (317)       3 (11)    115 (377)     52 (170)       4 (12)
     total).
Vibratory Driving/Extraction:

[[Page 17796]]

 
    12-inch Composite Barrier Pile    178.....................  168 RMS................      18 (58)        2 (5)      26 (86)      11 (35)        1 (2)
     (5 per day).
    36-inch steel pipe pile (4 per    195.....................  170 RMS................      17 (57)        3 (9)      23 (76)      12 (39)        2 (5)
     day).
    20-inch steel pipe pile (4 per    180.....................  163 RMS................       8 (25)        1 (4)      10 (34)       5 (17)        1 (2)
     day).
    Wood and concrete pile            No Data.................  152 RMS................        2 (7)       0 (<1)       3 (10)        1 (4)       0 (<1)
     extraction (12 per day).
--------------------------------------------------------------------------------------------------------------------------------------------------------


          Table 7--Radial Distances to Level B Harassment Isopleths During Impact and Vibratory Driving
----------------------------------------------------------------------------------------------------------------
                                                                  Source levels at 10 meters       Distance to
                                                                             (dB)                threshold 160/
                           Pile type                           --------------------------------    120 dB RMS
                                                                                                  (Level B)  in
                                                                     Peak             RMS        meters  (feet)
----------------------------------------------------------------------------------------------------------------
Attenuated Impact Driving (with Bubble curtain):
    60-inch steel pipe (1 per day)............................             203             188       736 (2,413)
    24-inch square concrete (1-2 per day).....................             191             173          45 (147)
Impact Pile Proofing (no Bubble curtain):
    36-inch steel pipe pile (2 total).........................             210             193     1,585 (5,198)
Vibratory Driving/Extraction:
    12-Inch Composite Barrier Piles (5 per day)...............             178             168   15,849 (51,984)
    36-inch steel pipe pile (4 per day).......................             180             170    3,162 (10,372)
    20-inch steel pipe pile (4 per day).......................             180             163     1,413 (4,633)
    Wood and concrete pile extraction (12 per day)............               *             152     1,359 (4,459)
----------------------------------------------------------------------------------------------------------------
* No Data Available.

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.
    For the 2019 IHA application, a combination of nearby haul-out 
occupancy and at-sea densities were used to develop take estimates, in 
order to account for both local movements of harbor seals that haul out 
at Castro Rocks and other individuals that may be foraging in the more 
distant part of the Level B Harassment zone. By using hydroacoustic 
data collected in 2018, extent of the harassment zones was refined for 
vibratory driving of steel piles and attenuated impact driving of 
concrete piles by using the transmission loss measured during 2018 
project (20logr). As the Level B Harassment zones estimated for the 
2019 IHA are generally more localized, only the occupancy from the 
local Castro Rocks haul-out is used.
    Castro Rocks, located approximately 1.3 km northwest of the project 
site, is the largest harbor seal haul out site in the northern part of 
San Francisco Bay and is the second largest pupping site in the Bay 
(Green et al. 2002). Tidal stage is a major controlling factor of haul 
out usage at Castro Rocks with more seals present during low tides than 
high tide periods (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 seals in the water 
around Castro Rocks will vary throughout the work period. Pile driving 
would occur intermittently during the day with average active driving 
times typically of a few hours per day, so varying sets of animals may 
be hauled out or in the water. However, there are no systematic counts 
available for accurately estimating the number of seals that may be in 
the water near the Long Wharf at any given time. The National Park 
Service provided recent data indicating that up to 176 seals could be 
present each day at Castro Rocks. This value was conservatively based 
on the highest mean plus the standard error of harbor seals observed at 
Castro Rocks per day (Codde, S. and S. Allen. 2013, 2015, and 2017), a 
value of 176 seals. The 2018 draft Long Wharf marine mammal monitoring 
report indicated that 24 harbor seals were observed within the Level B 
harassment zone and zero individuals were observed within the Level A 
harassment zone over 10 days of pile driving, which equals less than 1 
percent of the authorized number of harbor seals with an average of 2.4 
animals per day. The maximum number observed per day was six.
    Since there are no California sea lion haul-outs in the vicinity of 
the project area, relatively few animals are expected to be present. 
However, monitoring for the RSRB did observe limited numbers in the 
north and central portions of the Bay during working hours. During 
monitoring for the San Francisco-Oakland Bay Bridge (SFOBB) Project in 
the central Bay, 83 California sea lions were observed in the vicinity 
of the bridge over a 17-year period from 2000-2017, and from these 
observations, an estimated at-sea density of 0.16 animals per square 
kilometer is derived (NMFS 2018). This bridge is located approximately 
25 km south of the LWMEP location and is considered by NMFS to be the 
best available information. The 2018 Long Wharf draft monitoring report 
did not record any observations of sea lions.
    Small numbers of northern elephant seal may haul out or strand on 
coastline

[[Page 17797]]

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 0.16 
animal per square mile (0.06 animal per square kilometer) (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 proposed action are likely to be lower. 
Additionally, this species was not observed by the marine mammal 
observers in the vicinity of the Long Wharf during 2018 pile driving 
monitoring.
    The occurrence 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. Equatorial sea surface temperatures are 
above average across most of the Pacific Ocean this year, and El 
Ni[ntilde]o is expected to continue through winter of 2019 and into 
spring (NOAA 2019). There are no estimated at-sea densities for this 
species in San Francisco Bay and no seals were recorded during 2018 
Long Wharf marine mammal monitoring.
    A small but growing population of harbor porpoises utilizes San 
Francisco Bay which are typically spotted in the vicinity of Angel 
Island and the Golden Gate (6 and 12 kilometers [3.7 and 7.5 miles] 
southwest respectively) and the vicinity of Treasure Island (Caltrans 
2018). However, they may occur in other areas in the Central Bay in low 
numbers, including the project area. Based on monitoring conducted for 
the SFOBB project in 2017, an in-water density of 0.17 animals per 
square kilometer has been estimated by Caltrans for this species (NMFS 
2018). No members of this species were recorded during 2018 during pile 
driving activities at LWMEP.
    Bottlenose dolphins are typically found close to the Golden Gate 
Bridge when they are observed in San Francisco Bay. There are no 
estimated at-sea densities for this species in San Francisco Bay 
available for calculating a take estimate. Beginning in 2015, two 
individuals have been observed frequently in the vicinity of Oyster 
Point (GGCR 2018; Perlman, 2017). The average reported group size for 
bottlenose dolphins is five. Reports show that a group normally comes 
into San Francisco Bay, is near Yerba Buena Island once per week for 
approximately two (2) weeks and then leaves (NMFS, 2017).
    Gray whales have been observed entering 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 
miles) past the Golden Gate. However, gray whales have occasionally 
been sighted as far north as San Pablo Bay. Pile driving is not 
expected to occur during the February-May period, and gray whales are 
not likely to be present at other times of year. No whales were 
observed as part of 2018 Long Wharf marine mammal monitoring 
activities.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    When density data was available, take for the project was 
calculated by multiplying the density times the harassment zone (km\2\) 
associated with pile driving activities that are underway times the 
number of construction days. Since density data was only available for 
harbor seals, harbor porpoises, and California sea lions, these were 
the only species whose take was calculated using this methodology. For 
species without density information, information on average group size 
or local observational data was used as described below.

Pacific Harbor Seal

    Chevron initially estimated that all harbor seals (176) at Castro 
Rocks would be exposed to noise that reaches the threshold for Level B 
harassment on every day on which there was pile driving. The areas of 
the Level A harassment zones in which take by injury could occur were 
determined by subtracting the shutdown zone areas from Level A 
harassment zone areas. Estimated Level A take for impact driving of the 
60-inch and 36-inch steel piles was then 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. 
This resulted in an estimated 11,968 takes by Level B harassment and 
513 takes by Level A harassment. However, given that the 2018 IHA, 
overestimated the amount of authorized seal takes by a considerable 
margin (based on recorded <1 percent of the authorized number of takes 
observed), this initial 2019 estimate is likely to also be too high. 
Therefore, NMFS proposes to conservatively assume that only 25 percent 
of these initially calculated take numbers will actually occur, 
resulting in a proposal of 2,992 takes by Level B harassment and 128 
takes by Level A harassment. Even in consideration of animals that were 
likely taken but not detected, this results in a likely conservative 
average of 47 harbor seal takes per day.

                    Table 8--Level A and Level B Harassment Estimate for Pacific Harbor Seal
                                                    [Per Day]
----------------------------------------------------------------------------------------------------------------
                                                                                      Estimated take per day
                                  Level B zone   Exclusion zone   Level A zone,  -------------------------------
           Pile type                 (sq km)       radius (m)     minus shutdown   Level B take    Level A take
                                                                   zone (sq km)   per day--total  per day--total
----------------------------------------------------------------------------------------------------------------
                                                Vibratory Driving
----------------------------------------------------------------------------------------------------------------
12-inch composite pile.........          165.62              15                0             176              NA
36-inch steel pipe pile........           22.90              15                0             176              NA
20-inch steel pipe pile........            5.72              10                0             176              NA
Timber/Concrete Pile Removal...            5.33              15                0             176              NA
----------------------------------------------------------------------------------------------------------------
                                                 Impact Driving
----------------------------------------------------------------------------------------------------------------
24-inch concrete pile..........            0.01              20                0             176              NA
60-inch steel pile.............            1.70              30             0.62             176           64.06
----------------------------------------------------------------------------------------------------------------
                                                 Impact Proofing
----------------------------------------------------------------------------------------------------------------
36-inch steel pile.............            6.92              30             0.01             176            0.14
----------------------------------------------------------------------------------------------------------------


[[Page 17798]]

    For impact pile driving of the 60-inch steel piles, the proposed 
shutdown zones (30 m) are notably smaller than the Level A harassment 
zone and the applicant has accordingly requested take by Level A 
harassment for harbor seal so that pile driving can be completed on 
schedule without frequent shutdowns. Individuals occurring within the 
Level A harassment zone but outside of the shut-down zone may 
experience Level A harassment, if they reside in that area for a long 
enough duration. However, these animals can be highly mobile, and 
remaining within the small injury zone for an extended period is 
unlikely, though it could occur.

California Sea Lion

    Monitoring data from the SFOBB Project over a 17-year period was 
used to develop a density of 0.16 California sea lions per square 
kilometer. This density and the areas of the potential Level B 
Harassment zones are used in Table 9. Level A harassment take of this 
species is not requested, due to the small size of the Level A 
harassment zone for otariid pinnipeds.

      Table 9--Level B Harassment Estimate for California Sea Lion
                                [per day]
------------------------------------------------------------------------
                                                           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
------------------------------------------------------------------------
12-inch composite pile..................          165.62           26.50
36-inch steel pipe pile.................           22.90            3.66
20-inch steel pipe pile.................            5.72            0.91
Timber/Concrete Pile Removal............            5.33            0.85
------------------------------------------------------------------------
                             Impact Driving
------------------------------------------------------------------------
24-inch concrete pile...................            0.01            0.01
60-inch steel pile......................            1.70            0.27
-----------------------------------------
             Impact Proofing
------------------------------------------------------------------------
36-inch steel pile......................            6.92            1.11
------------------------------------------------------------------------

Harbor Porpoise

    Based on monitoring conducted for the SFOBB project in 2017, an in-
water density of 0.17 animals per square kilometer has been estimated 
by Caltrans for this species (NMFS 2018). Using this in-water density 
and the areas of potential Level A and Level B harassment, take is 
estimated for harbor porpoise as provided in Table 10. Level A 
harassment zone areas in which PTS could occur were determined by 
subtracting the shutdown zone areas from Level A harassment zone areas. 
Level A take is not requested for vibratory driving.

                  Table 10--Level A and Level B Harassment Estimate for Pacific Harbor Porpoise
                                                    [Per day]
----------------------------------------------------------------------------------------------------------------
                                                                                      Level B
                                                                   Level A zone,     estimate        Estimated
            Pile type              Level B zone   Exclusion zone       minus      Central Bay in-  Level A take
                                      (km\2\)           (m)       shutdown  zone    water--0.17       per day
                                                                      (km\2\)        per km\2\
----------------------------------------------------------------------------------------------------------------
                                                Vibratory Driving
----------------------------------------------------------------------------------------------------------------
12-inch composite barrier pile..          165.62              50              NA           28.16              NA
36-inch steel pipe pile.........           22.90              50              NA            3.89              NA
20-inch steel pipe pile.........            5.72              50              NA            0.97              NA
Timber/Concrete Pile Removal....            5.33              50              NA            0.91              NA
----------------------------------------------------------------------------------------------------------------
                                                 Impact Driving
----------------------------------------------------------------------------------------------------------------
24-inch concrete pile...........            0.01              50               0            0.01               0
60-inch steel pile..............            0.21              50            0.23            0.29            0.52
----------------------------------------------------------------------------------------------------------------
                                                 Impact Proofing
----------------------------------------------------------------------------------------------------------------
36-inch steel pile..............            0.31              80               0            1.18           <0.01
----------------------------------------------------------------------------------------------------------------


[[Page 17799]]

Northern Elephant Seal

    As noted above, elephant seal densities are expected to be 
extremely low. Therefore, Chevron did not use density data to calculate 
take. Additionally, this species was not observed by the marine mammal 
observers in the vicinity of the LWMEP during 2018 pile driving marine 
mammal monitoring activities. Therefore, Caltrans will conservatively 
assume that a lone northern elephant seal may enter the Level B 
Harassment area once per every three days during pile driving. As such, 
Chevron requests and NMFS proposes to authorize a total of 23 takes by 
Level B harassment. Level A harassment of this species is not expected 
to occur.

Northern Fur Seal

    With weak El Ni[ntilde]o conditions predicted to continue into 
spring and, perhaps, summer (NOAA 2019). There is a chance that fur 
seals could occur near the project area. Since there are no estimated 
at-sea densities for this species in San Francisco Bay, Chevron 
conservatively requested and NMFS proposes to authorize 10 takes of fur 
seals by Level B harassment. Level A harassment of this species is not 
anticipated.

Bottlenose Dolphin

    As noted above, there are no estimated at-sea densities for this 
species in San Francisco Bay available for calculating a take estimate 
although they have been observed. 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. Assuming the dolphins come into San 
Francisco Bay once every 10 days, 34 takes would be anticipated, if the 
group enters the areas over which the Level B harassment thresholds may 
be exceeded.

Gray Whale

    Gray whales are most often sighted in the Bay between February and 
May. However, LWMEP pile driving is not expected to occur during this 
time, and gray whales are unlikely to be present at other times of 
year. However, should pile driving occur during the northward migration 
period, Chevron requests and NMFS proposes to authorize two (2) Gray 
whale takes by Level B harassment.
    The Level B Harassment estimates shown in Table 11 are based on the 
number of individuals assumed to be exposed per day, the number of 
piles driven per day and the number of days of pile driving expected 
based on an average installation rate. The Level A Harassment estimates 
for harbor seals and harbor porpoises are derived by taking the Level B 
Harassment estimates and multiplying it by the fractional ratio of the 
area of the Level A zone to the Level B zone as shown in Table 12. 
Values for harbor seals in both Table 11 and Table 12 are shown as 25 
percent of total sums. Take by Level A harassment is not proposed for 
any other species.

                                                           Table 11--Summary of Estimated Take Level B Harassment for 2019 Work Season
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                Species
                                                                              Number of    Number of  ------------------------------------------------------------------------------------------
                 Pile type                          Pile driver type            piles       driving                                 Harbor                 N. elephant                Bottlenose
                                                                                              days     Harbor seal  CA sea lion    porpoise    Gray whale      seal     N. fur seal    dolphin
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
60-inch steel pipe.........................  Impact........................            8            8        1,408         2.18         2.31           NA         2.66           NA           NA
36-inch steel pipe pile **.................  Vibratory.....................            8            4          704        14.66        15.57           NA         1.33           NA           NA
36-inch steel pipe pile....................  Impact Proofing...............            2            1          176         1.11         1.18           NA         0.33           NA           NA
20-inch steel pipe pile **.................  Vibratory.....................            8            4          704         3.66         3.89           NA         1.33           NA           NA
Concrete pile removal......................  Vibratory.....................            5            1          176         0.91         0.97           NA         0.33           NA           NA
24-inch concrete...........................  Impact........................           39           30        5,280         0.03         0.04           NA           10           NA           NA
12-inch composite pile installation........  Vibratory.....................           52           11        1,936       291.50       309.72           NA         3.66           NA           NA
Timber pile removal........................  Vibratory.....................          106            9        1,584         7.68         8.16           NA            3           NA           NA
                                                                            --------------------------------------------------------------------------------------------------------------------
    Total Proposed Take by Species (2019)..  ..............................  ...........  ...........      * 2,992          322          342            2           23           10           34
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Stated value equivalent to 25% of total sum.


                   Table 12--Summary of Estimated Take Level A Harassment for 2019 Work Season
----------------------------------------------------------------------------------------------------------------
                                                     Number of       Number of                        Harbor
           Pile type            Pile driver type       piles       driving days     Harbor seal      porpoise
----------------------------------------------------------------------------------------------------------------
60-inch steel pipe............  Impact..........               8               8          512.49            4.18
36-inch steel pipe pile.......  Vibratory.......               8               4               0               0
36-inch steel pipe pile.......  Impact Proofing.               2               1            0.14           <0.01
20-inch steel pipe pile **....  Vibratory.......               8               4               0               0
Concrete pile removal.........  Vibratory.......               5               1               0               0
24-inch concrete..............  Impact..........              39              30               0               0
12-inch composite pile          Vibratory.......              52              11               0               0
 installation.
Timber pile removal...........  Vibratory.......             106               9               0               0
                                                 ---------------------------------------------------------------

[[Page 17800]]

 
    Total Proposed Take.......  ................  ..............  ..............           * 128               4
----------------------------------------------------------------------------------------------------------------
* Stated value equivalent to 25% of total sum.


                    Table 13--Proposed Authorized Take and Percentage of Stock or Population
----------------------------------------------------------------------------------------------------------------
                                                                                                    Percent
                                                                                                 (instances of
             Species                       Stock         Authorized  Level  Authorized  Level   take compared to
                                                              A takes            B takes           population
                                                                                                   abundance)
----------------------------------------------------------------------------------------------------------------
Harbor seal......................  California..........                128              2,992              10.07
California sea lion..............  Eastern U.S.........  .................                322              <0.01
Harbor porpoise..................  San Francisco--                       4                342               3.49
                                    Russian River.
Northern elephant seal...........  California Breeding.  .................                 23              <0.01
Gray whale.......................  Eastern North         .................                  2              <0.01
                                    Pacific.
Northern fur seal................  California..........  .................                 10              <0.01
Bottlenose Dolphin...............  California Coastal..  .................                 34               7.51
----------------------------------------------------------------------------------------------------------------

Proposed 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, as 
well as subsistence uses. This considers the nature of the potential 
adverse impact being mitigated (likelihood, scope, range). It further 
considers the likelihood that the measure will be effective if 
implemented (probability of accomplishing the mitigating result if 
implemented as planned), the likelihood of effective implementation 
(probability implemented as planned), and;
    (2) the practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.

Mitigation for Marine Mammals and Their Habitat

    The following mitigation measures are proposed for Chevron's LWMEP:
    Noise Attenuation--Bubble curtains will be used during all impact 
pile driving of 60-inch steel shell pile and 24-inch square concrete 
piles to interrupt acoustic pressure and reduce impact on marine 
mammals. The use of bubble curtains is expected to reduce underwater 
noise levels by approximately 7 dB, which greatly reduces the area over 
which the cumulative SEL threshold for Level A Harassment may be 
exceeded. Bubble curtains would also decrease the size of the Level B 
harassment zone, reducing the numbers of marine mammals affected by 
potential behavioral impacts.
    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.
    Establishment of a Shutdown Zone--For all pile driving/removal and 
drilling activities, Chevron will establish shutdown zones. 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 SPLs are expected to reach or exceed the cumulative SEL 
thresholds for Level A harassment as provided in Table 14.

                                       Table 14--Shutdown Zones for LWMEP
----------------------------------------------------------------------------------------------------------------
                                                              Exclusion zones meters
 Project element requiring pile --------------------------------------------------------------------------------
          installation            Low-frequency   Mid-frequency   High-frequency      Phocid          Otariid
                                    cetaceans       cetaceans       cetaceans        pinnipeds       pinnipeds
----------------------------------------------------------------------------------------------------------------
Attenuated Impact Driving (with
 bubble curtain):
    60-inch steel pipe.........             840              30               50              30              35
    24-inch square concrete....              20              10               50              15              10
Impact Pile Proofing (no bubble
 curtain):
    36-inch steel pipe pile....             100              10               80              30              10

[[Page 17801]]

 
Vibratory Driving/Extraction:
    12-inch Composite Barrier                20              10               50              15              10
     Pile......................
    36-inch steel pipe pile....              20              10               50              15              10
    20-inch steel pipe pile....              10              10               50              10              10
    Wood and concrete pile                   10              10               50              10              10
     extraction................
----------------------------------------------------------------------------------------------------------------

    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 450 meters and harbor seals and 
extending to 990 for harbor porpoises. These are areas beyond the 
shutdown zone in which animals could be exposed to sound levels that 
could result in Level A harassment in the form of 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 as shown in Table 7. Monitoring zones provide utility for 
observing by establishing monitoring protocols for areas adjacent to 
the shutdown zones. Monitoring zones also 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. Level B harassment 
exposures will be recorded and extrapolated based upon the number of 
observed take and the percentage of the Level B harassment zone that 
was not visible.
    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.
    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.
    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.
    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 
or 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.
    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 the area or an observation time period of 15 
minutes has elapsed.
    Based on our evaluation of the Chevron's proposed measures, as well 
as other measures considered by NMFS, we have preliminarily determined 
that the proposed 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.

Proposed 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 
proposed 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:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;

[[Page 17802]]

     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Visual Monitoring

    The following visual monitoring measures are required as part of 
the issued IHA.
     One day of biological monitoring would occur within one 
week before the project's start date to establish baseline 
observations;
     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;
     Monitoring locations will be established at locations 
offering best views of the monitoring zone;
     Monitoring would be conducted 30 minutes before, during, 
and 30 minutes after pile driving/removal and drilling activities. In 
addition, observers shall record all incidents of marine mammal 
occurrence, regardless of distance from activity, and shall document 
any behavioral reactions in concert with distance from piles being 
driven or removed. Pile driving/removal and drilling activities include 
the time to install or remove a single pile or series of piles, as long 
as the time elapsed between uses of the pile driving equipment is no 
more than 30 minutes.
     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;
     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;
     At least two PSOs will be actively scanning the monitoring 
zone during all pile driving activities;
     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;
     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.

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. Hydroacoustic monitoring would be conducted by a 
qualified monitor during pile extraction and driving activities as 
described in the Hydroacoustic Monitoring plan and will likely include 
the following during 2019:
     Acoustic monitoring for at least two (2) 60-inch steel 
pipe piles at Berth 4;
     Acoustic monitoring for at least one (1) 36-inch pile at 
Berth 4;
     Acoustic monitoring for at least one (1) 20-inch pile at 
Berth 4;
     Acoustic monitoring of a representative pile removal; and
     Acoustic monitoring of two (2) composite piles.

Proposed Reporting Measures

    A draft marine mammal monitoring report would be submitted to NMFS 
within 90 days after the completion of pile driving and removal and 
drilling activities. It will include an overall description of work 
completed, a narrative regarding marine mammal sightings, and 
associated PSO data sheets. Specifically, the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring;
     Construction activities occurring during each daily 
observation period, including how many and what type of piles were 
driven or removed and by what method (i.e., impact or vibratory);
     Weather parameters and water conditions during each 
monitoring period (e.g., wind speed, percent cover, visibility, sea 
state);
     The number of marine mammals observed, by species, 
relative to the pile location and if pile driving or removal was 
occurring at time of sighting;
     Age and sex class, if possible, of all marine mammals 
observed;
     PSO locations during marine mammal monitoring;
     Distances and bearings of each marine mammal observed to 
the pile being driven or removed for each sighting (if pile driving or 
removal was occurring at time of sighting);
     Description of any marine mammal behavior patterns during 
observation, including direction of travel;
     Number of individuals of each species (differentiated by 
month as appropriate) detected within the monitoring zone, and 
estimates of number of marine mammals taken, by species (a correction 
factor may be applied to total take numbers, as appropriate);
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensued, and resulting behavior of the animal, if 
any;
     Description of attempts to distinguish between the number 
of individual animals taken and the number of incidences of take, such 
as ability to track groups or individuals; and
     Level B harassment exposures recorded by PSOs must be 
extrapolated based upon the number of observed takes and the percentage 
of the Level B harassment zone that was not visible.
    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

[[Page 17803]]

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:
     Description of the incident;
     Environmental conditions (e.g., Beaufort sea state, 
visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     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, video footage (if available), or other documentation of 
the stranded animal sighting to NMFS and the Marine Mammal Stranding 
Network.

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 LWMEP project 
as outlined previously have the potential to injure, disturb or 
displace marine mammals. Specifically, the proposed activities may 
result in Level B harassment (behavioral disturbance) for seven marine 
mammal species authorized for take from underwater sound generated 
during pile driving and removal operations. Level A harassment in the 
form of limited PTS may also occur to animals of two species. No marine 
mammal stocks for which incidental take authorization are listed as 
threatened or endangered under the ESA or determined to be strategic or 
depleted under the MMPA. No serious injuries or mortalities are 
anticipated to occur as a result of Chevron's pile driving activities.
    A limited number of animals (128 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 
60-inch steel and 36-inch steel piles. The degree of injury is expected 
to be mild and is not likely to affect the reproduction or 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. 
However, this is unlikely to result in any significant realized 
decrease in fitness for the affected individuals or stocks for which 
take is authorized. While harbor seals from Castro Rocks may experience 
some temporary low-level behavioral impacts, the number of seals 
potentially affected is conservatively estimated at approximately 10 
percent of the stock. This number, however, likely includes multiple 
takes of the same individuals. Furthermore, Castro Rocks and the LWMEP 
location represent a small portion of the range of the California stock 
of harbor seal. These two factors indicate that a much lower percentage 
of the stock would potentially be affected and, therefore, no adverse 
impacts to the stock as a whole are expected.
    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 relatively short duration of driving 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. Furthermore, there are no biologically important areas 
identified in the project area.
    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 during 
impact driving 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

[[Page 17804]]

behavioral harassment. Furthermore, the pile driving activities 
analyzed here are similar to, or less impactful than, numerous 
construction activities conducted in other 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 preliminary 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:
     No mortality is anticipated or authorized;
     Anticipated incidences of Level A harassment would be in 
the form of a small degree of PTS to a limited number of animals;
     Anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior;
     No biologically important areas have been identified in 
the vicinity of the project area;
     The small percentage of the stock that may be affected by 
project activities (<10.07 percent for all stocks); and
     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 proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    Table 13 depicts the number of animals that could be exposed to 
Level A and Level B harassment from work associated with Chevron's 
proposed project. The analysis provided indicates that authorized take 
would account for no more than 10.07 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 proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily 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.

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 proposed for 
authorization 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.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to Chevron for conducting pile driving and removal 
activities at Chevron's Long Wharf from June 1, 2019 through May 31, 
2020, provided the previously mentioned mitigation, monitoring, and 
reporting requirements are incorporated. A draft of the proposed IHA 
can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed 
action. We also request comment on the potential for renewal of this 
proposed IHA as described in the paragraph below. Please include with 
your comments any supporting data or literature citations to help 
inform our final decision on the request for MMPA authorization.
    On a case-by-case basis, NMFS may issue a one-year IHA renewal with 
an expedited public comment period (15 days) when (1) another year of 
identical or nearly identical activities as described in the Specified 
Activities section is planned or (2) the activities would not be 
completed by the time the IHA expires and a second IHA would allow for 
completion of the activities beyond that described in the Dates and 
Duration section, provided all of the following conditions are met:
     A request for renewal is received no later than 60 days 
prior to expiration of the current IHA.
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
proposed Renewal are identical to the activities analyzed under the 
initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take 
because only a subset of the initially analyzed activities remain to be 
completed under the Renewal); and
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
     Upon review of the request for renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: April 23, 2019.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2019-08415 Filed 4-25-19; 8:45 am]
 BILLING CODE 3510-22-P