[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
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Number of Number of
Pile type Pile driver type piles driving days
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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
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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\
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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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).
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Order Carnivora--Superfamily Pinnipedia
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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).
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\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]
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Hearing group Generalized hearing range *
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Low-frequency (LF) cetaceans (baleen 7 Hz to 35 kHz.
whales).
Mid-frequency (MF) cetaceans 150 Hz to 160 kHz.
(dolphins, toothed whales, beaked
whales, bottlenose whales).
High-frequency (HF) cetaceans (true 275 Hz to 160 kHz.
porpoises, Kogia, river dolphins,
cephalorhynchid, Lagenorhynchus
cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) 50 Hz to 86 kHz.
(true seals).
Otariid pinnipeds (OW) (underwater) 60 Hz to 39 kHz.
(sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth 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
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PTS onset acoustic thresholds \*\ (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
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Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4: LE,MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE, HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: Lpk,flat: 218 dB; Cell 8: LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
LE,OW,24h: 203 dB.
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* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [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