[Federal Register Volume 82, Number 113 (Wednesday, June 14, 2017)]
[Notices]
[Pages 27240-27251]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-12295]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF246


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

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
Chevron to incidentally harass, by Level B harassment only, marine 
mammals during construction activities associated with the Richmond 
Refinery Long Wharf Maintenance and Efficiency Project (WMEP) in San 
Francisco Bay, California.

DATES: The Authorization is in effect for one year beginning January 1, 
2018 through December 31, 2018.

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

SUPPLEMENTARY INFORMATION: 

Availability

    An electronic copy of Chevron's application and supporting 
documents, as well as a list of the references cited in this document, 
may be obtained online at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing these documents, please 
call the contact listed above (see FOR FURTHER INFORMATION CONTACT).

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.

[[Page 27241]]

    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as an 
impact resulting from the specified activity that cannot be reasonably 
expected to, and is not reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.
    The MMPA states that the term ``take'' means to harass, hunt, 
capture, kill or attempt to harass, hunt, capture, or kill any marine 
mammal.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering (Level B harassment).

Summary of Request

    On July 21, 2014, NMFS received a request from Chevron for 
authorization to take marine mammals incidental to pile driving and 
removal associated with the WMEP in San Francisco Bay, California. The 
project was delayed due to funding constraints. Chevron submitted a 
revised version of the request on November 16, 2016, which was deemed 
adequate and complete on January 12, 2017. Chevron will undertake the 
WMEP in order to comply with current Marine Oil Terminal Engineering 
and Maintenance Standards (MOTEMS) requirements and to improve safety 
and efficiency at the Long Wharf. Construction would start in 2018, and 
be complete by the fourth quarter of 2022. Therefore, Chevron expects 
to request additional IHAs in association with this multi-year project. 
The effective dates for this first IHA would be from January 1, 2018 
through December 31, 2018. The use of both vibratory and impact pile 
driving during pile removal and installation during the four-year 
construction period is expected to produce underwater sound at levels 
that have the potential to result in Level B (behavioral) harassment of 
marine mammals. However, only impact driving will occur during 2018 and 
will be covered under the issued IHA. Species expected to occur in the 
area and for which take is authorized include California sea lion 
(Zalophus californianus) and Pacific harbor seal (Phoca vitulina).

Description of the Specified Activity

Overview

    Chevron's Richmond Refinery Long Wharf (Long Wharf) is the largest 
marine oil terminal in California. Its operations are regulated 
primarily by the California State Lands Commission (CSLC) through a 
State Lands lease, Article 5 of CSLC regulations, and MOTEMS 
(California Building Code (CBC) Chapter 31F). The Long Wharf has 
existed in its current location since the early 1900s (Figure 1-1 in 
Application). The Berth 2 fender system (timber pile and whaler) was 
designed and installed in 1940. Marine loading arms, gangways, and 
fender systems at Berths 1, 3 and 4 were installed in 1972. The Berth 4 
fender panels were replaced in 2011 and the Berth 1 fender panels were 
replaced in 2012. 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 WMEP is to comply with current MOTEMS 
requirements and to improve safety and efficiency at the Long Wharf. To 
meet MOTEMS requirements, the fendering system at Berth 2 is being 
updated and the Berth 4 loading platform will be seismically 
retrofitted to stiffen the structure and reduce movement of the Long 
Wharf in the event of a level 1 or 2 earthquake. Safety will be 
improved by replacing gangways and fire monitors. Efficiency at the 
Long Wharf will be improved by updating the fender system configuration 
at Berth 4 to accommodate newer, more fuel efficient vessels and thus 
reduce idling time for vessels waiting to berth. Further, efficiency 
will be improved by updating the fender system at Berth 1 to 
accommodate barges, enabling balanced utilization across Berths 1, 2, 
and 3.

Dates and Duration

    Project construction will start in 2018 and be completed by the 
fourth quarter of 2022. Pile driving activities will be timed to occur 
within the standard NMFS work windows for listed fish species (June 1 
through November 30) during those 4 years. The effective date for this 
initial IHA will be from January 1, 2018 through December 31, 2018. 
Over the course of the multi-year project, 249 piles of various sizes 
will be installed via impact and vibratory driving; 161 piles will be 
removed via vibratory removal; and 209 driving days are planned. During 
the first year of construction covered under this IHA, 8,24-inch 
concrete piles will be installed by impact driving over 4 workdays at 
Berth 2.

Specified 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. The 
South Bay is located south of the San Francisco-Oakland Bay Bridge. San 
Pablo Bay extends north of the RSRB.

Detailed Description of Specified Activities

    The complete multi-year project will involve modifications at 4 
berths (Berths 1, 2, 3, and 4) as shown in Figure 1-1 in the 
Application. Planned modifications to the Long Wharf include replacing 
gangways and cranes, adding new mooring hooks and standoff fenders, 
adding new dolphins and catwalks, and modifying the fire water system 
at Berths 1, 2, 3 and/or 4, as well as the seismic retrofit to the 
Berth 4 loading platform. The type and numbers of piles to be 
installed, as well as those that will be removed, are summarized in 
Table 1-1 in the Application and an overview of the modifications at 
Berths 1 to 4 are shown in Figure 1-2 in the Application.
    The combined modifications to Berths 1-4 will require the 
installation of 141 new concrete piles to support new and replacement 
equipment and their associated structures. The Berth 4 loading platform 
will add 8, 60-inch diameter steel piles as part of the seismic 
retrofit.
    The project will also add 4 clusters of 13 composite piles each (52 
total) as markers and protection of the new batter (driven at an angle) 
piles on the east side of the Berth 4 retrofit. The project will remove 
106 existing timber piles, two existing 18-inch and two existing 24-
inch concrete piles. A total of 12 24-inch temporary steel piles will 
also be installed and removed during the seismic retrofit of Berth 4.
    The modifications at each berth are summarized below.
    Modifications at Berth 1 include the following:

[[Page 27242]]

     Replace gangway to accommodate barges and add a new raised 
fire monitor.
     Construct a new 24' x 20' mooring dolphin and hook to 
accommodate barges.
     Construct a new 24' x 25' breasting dolphin and 13' x 26' 
breasting point with standoff fenders to accommodate barges. The new 
breasting dolphin will require removal of an existing catwalk and two 
piles and moving a catwalk to a slightly different location to maintain 
access to currently existing dolphins. A new catwalk will be installed 
to provide access to the new breasting dolphin.
     A portion of the existing gangway will be removed. The 
remaining portion is used for other existing services located on its 
structure.
    Much of this work will be above the water or on the deck of the 
terminal. The mooring dolphin and hook, breasting dolphin, and new 
gangway will require installation of 42 new 24-inch square concrete 
piles using impact driving methods.
    Modifications at Berth 2 include the following:
     Install new gangway to replace portable gangway and add a 
new elevated fire monitor.
     Replace one bollard with a new hook.
     Install four new standoff fenders (to replace timber 
fender pile system).
     Replace existing auxiliary and hose cranes and vapor 
recovery crane to accommodate the new standoff fenders.
     Remove the existing timber fender pile system along the 
length of the Berth (~650 ft.)
     Three (3) existing brace piles (22-inch square concrete 
jacketed timber piles) would be removed by cutting below the mud line 
if possible.
    These modifications will require the installation of 51 new 24-inch 
square concrete piles, using impact driving methods, to support the 
gangway, standoff fenders, hose crane, and auxiliary crane. To keep 
Berth 2 operational during construction, four temporary fenders will be 
installed, supported by 36 temporary 14-inch H-piles driven using 
vibratory methods. It is expected that the H-piles would largely sink 
under their own weight and would require very little driving. The H-
piles and temporary fenders will be removed once the permanent standoff 
fenders are complete. The auxiliary and hose cranes are being replaced 
with cranes with longer reach to accommodate the additional distance of 
the new standoff fenders. The new vapor recovery crane would be mounted 
on an existing pedestal and not require in-water work.
    Modifications at Berth 3 include the following:
     Install new fixed gangway to replace portable gangway and 
add a new raised fire monitor. The gangway would be supported by four, 
24-inch square concrete piles. This would be the only in-water work for 
modifications at Berth 3.
    Modifications at Berth 4 include the following:
     Install two new 36' x 20' dolphins with standoff fenders 
(two per dolphin) and two catwalks.
     Seismically retrofit the Berth 4 loading platform 
including bolstering and relocation of piping and electrical 
facilities.
    The new fenders would add 44 new 24-inch square concrete piles.
    The seismic retrofit would structurally stiffen the Berth 4 Loading 
Platform under seismic loads. This will require cutting holes in the 
concrete decking and driving 8, 60-inch diameter hollow steel batter 
piles, using impact pile driving. To accommodate the new retrofit, an 
existing sump will be replaced with a new sump and two, 24-inch square 
concrete piles will be removed or cut to the mudline. The engineering 
team has determined that to drive the 60-inch batter piles, twelve 
temporary steel piles, 24 inches in diameter, will be needed to support 
templates for the angled piles during driving. Two templates are 
required, each 24 feet by 4 feet and supported by up to six 24-inch 
steel pipe piles. The templates will be above water. The project would 
also add 4 clusters of 13 composite piles each (52 total composite 
piles) as markers and protection of the new batter piles on the east 
side of the retrofit. See Table 1 for pile summary information.

[[Page 27243]]

[GRAPHIC] [TIFF OMITTED] TN14JN17.000

    Note that the issued IHA covers actions occurring during 2018 only. 
These actions include the installation of 8, 24-inch concrete piles by 
impact hammer driving over 4 workdays. These piles will replace 
existing auxiliary and hose cranes and vapor recovery crane at Berth 2. 
Impact installation will occur utilizing a DelMag D62 22 or similar 
diesel hammer, producing approximately 165,000 ft lbs maximum energy 
(may not need full energy) over a duration of approximately 20 minutes 
per pile.
    Mitigation, monitoring, and reporting measures are described in in 
detail later in the document (Mitigation and Monitoring and Reporting 
sections).

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to Chevron was 
published in the Federal Register on March 24, 2017 (82 FR 05025). That 
notice described, in detail, Chevron's activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals. During the 30-day public comment period, 
NMFS received comments from the Marine Mammal Commission. The Marine 
Mammal Commission recommended that NMFS issue the requested IHA, 
subject to inclusion of the mitigation, monitoring, and reporting 
measures as described in our notice of proposed IHA and the 
application. All measures proposed in the initial Federal Register 
notice are included within the IHA.

Description of Marine Mammals in the Area of the Specified Activity

    Although 35 species of marine mammals can be found off the coast of 
California, few species venture into San Francisco Bay, and only 
Pacific harbor seals (Phoca vitulina), California sea lions (Zalophus 
californianus), and harbor porpoises (Phocoena phocoena) make the Bay a 
permanent home. Small numbers of gray whales (Eschrichtius robustus) 
are regularly sighted in the Bay during their yearly migration, though 
most sightings tend to occur in the Central Bay near the Golden Gate 
Bridge. Two other species that may occasionally occur within San 
Francisco Bay include the Steller sea lion (Eumetopias jubatus) and 
bottlenose dolphin (Tursiops truncatus). Table 2 provides information 
about the species that are expected to potentially be present in the 
project area. A detailed description of the species likely to be 
affected by the project, including brief introductions to the species 
and relevant stocks as well as available information regarding 
population trends

[[Page 27244]]

and threats, and information regarding local occurrence, were provided 
in the Federal Register notice for the proposed IHA (82 FR 15025; March 
24, 2017). Since that time, we are not aware of any changes in the 
status of these species and stocks; therefore, detailed descriptions 
are not provided here. Please refer to that Federal Register notice for 
these descriptions. Please also refer to NMFS' Web site 
(www.nmfs.noaa.gov/pr/species/mammals/) for generalized species 
accounts.

                                     Table 2--Marine Mammals Potentially Present in the Vicinity of the Project \1\
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                                                       ESA/MMPA  status;
             Species                     Stock            strategic (Y/     Stock abundance     PBR \4\    Occurrence in/near           Seasonal
                                                         N)[thinsp] \2\      (CV/Nmin) \3\                       project
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Pacific harbor seal, Phoca        California Stock...  -/N                30,968 (-/27,348).        1,641  Common............  Year-round.
 vitulina.
California sea lion, Zalophus     Eastern U.S. Stock.  -/N                296,750 (-/               9,200  Uncommon..........  Year-round.
 californianus.                                                            153,337).
Harbor porpoise, Phocoena         San Francisco-       -/N                9,886 (0.51/6,625)           66  Common in the       Year-round.
 phocoena.                         Russian River                                                            vicinity of the
                                   Stock.                                                                   Golden Gate and
                                                                                                            Richardson's Bay,
                                                                                                            Rare elsewhere.
Gray whale, Eschrichtius          Eastern North        -/N                20,990 (0.05/               624  Rare to occasional  December-April.
 robustus.                         Pacific Stock.                          20,125).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Source: Carretta et al., 2016
\2\ ESA status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or
  designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR (see
  footnote 3) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\3\ CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For certain stocks of
  pinnipeds, abundance estimates are based upon observations of animals (often pups) ashore multiplied by some correction factor derived from knowledge
  of the species' (or similar species') life history to arrive at a best abundance estimate; therefore, there is no associated CV. In these cases, the
  minimum abundance may represent actual counts of all animals ashore.
\4\ Potential biological removal, defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a
  marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population size (OSP).

Potential Effects of the Specified Activity on Marine Mammals and Their 
Habitat

    The effects of underwater noise from construction activities for 
the project have the potential to result in behavioral harassment of 
marine mammals in the vicinity of the action area. The Federal Register 
notice for the proposed IHA (82 FR 15025; March 24, 2017) included a 
discussion of the potential effects of anthropogenic noise on marine 
mammals, therefore that information is not repeated here; please refer 
to the Federal Register notice for that information.
    The primary impacts to marine mammal habitat are associated with 
elevated sound levels produced by impact pile driving in the area. 
However, other potential impacts to the surrounding habitat from 
physical disturbance are also possible. The project would not result in 
permanent impacts to habitats used directly by marine mammals, such as 
haulout sites, but may have potential short-term impacts to food 
sources and minor impacts to the immediate substrate during 
installation of piles during the project. These potential effects are 
discussed in detail in the Federal Register notice for the proposed IHA 
(82 FR 15025; March 24, 2017), therefore, that information is not 
repeated here.

Estimated Take

    This section includes an estimate of the number of incidental takes 
expected to occur as a result of the specified activities considered 
pursuant to this IHA, which will inform both NMFS' consideration of 
whether the number of takes is small 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 be by Level B harassment only, in the form 
of disruption of behavioral for individual marine mammals resulting 
from exposure to impact driving. Based on the nature of the activity 
and the anticipated effectiveness of the mitigation measures (i.e., 
shutdown, soft start discussed in detail below in Proposed Mitigation 
section), Level A harassment is neither anticipated nor authorized. The 
death of a marine mammal is also a type of incidental take. However, as 
described previously, no mortality is anticipated or authorized for 
this activity. Below we describe how the take is estimated.
    In order to estimate the potential incidents of take that may occur 
incidental to the specified activity, we must first estimate the extent 
of the sound field that may be produced by the activity and then 
consider the sound field in combination with information about marine 
mammal density or abundance in the project area. We first provide 
information on applicable sound thresholds for determining effects to 
marine mammals before describing the information used in estimating the 
sound fields, the available marine mammal density or abundance 
information, and the method of estimating potential incidences of take.
    Sound Thresholds--NMFS uses sound exposure thresholds to determine 
when an activity that produces underwater sound might result in impacts 
to a marine mammal such that a take by harassment might occur. On 
August 4, 2016, NMFS released its Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on Marine Mammal Hearing (Guidance) (81 
FR 51694) (available at http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm). This new guidance established new thresholds for 
predicting auditory injury, which equates to Level A harassment under 
the MMPA. As will be discussed below, NMFS has revised Permanent 
Threshold Shift (PTS) (and Temporary Threshold Shift (TTS)) onset 
acoustic thresholds for impulsive and non-impulsive sound as part of 
its new acoustic guidance. The

[[Page 27245]]

Guidance does not address Level B harassment; therefore, NMFS uses the 
current acoustic exposure criteria to determine exposure to underwater 
noise sound pressure levels for Level B harassment (Table 5).
    During the installation of piles, the project has the potential to 
increase airborne noise levels. Airborne pile-driving root means square 
(RMS) noise levels above the NMFS airborne noise thresholds are not 
expected to extend to the Castro Rocks haul-out site, which is located 
650 meters (m) north of Long Wharf. In addition, the Castro Rocks haul 
out is subject to high levels of background noise from the Richmond 
Bridge, ongoing vessel activity at the Long Wharf, ferry traffic, and 
other general boat traffic. Any pinnipeds that surface in the area over 
which the airborne noise thresholds may be exceeded would have already 
been exposed to underwater noise levels above the applicable thresholds 
and thus would not result in an additional incidental take. Airborne 
noise is not considered further.
    Source Levels--Pile driving generates underwater noise that can 
potentially result in disturbance to marine mammals in the project 
area. In order to establish distances to PTS and behavioral harassment 
isopleths, the sound source level associated with a specific pile 
driving activity must be measured directly or estimated using proxy 
information. The intensity of pile driving sounds is greatly influenced 
by factors such as the material type and dimension of piles. To 
estimate the noise effects of the 24-inch square concrete piles planned 
for use in Year 1 of this project, Chevron reviewed sound pressure 
levels (SPLs) from other projects conducted under similar 
circumstances. These projects include the Pier 40 Berth Construction in 
San Francisco, and the Berth 22 and Berth 32 reconstruction projects at 
the Port of Oakland. However, NMFS elected to use data from only the 
Pier 40 project since 24-inch square concrete piles were installed at 
that location. At Berth 22 and Berth 32, 24-inch octagonal concrete 
piles were installed. The differences in pile shape may result in 
varying SPLs. Impact pile driving at Pier 40 resulted in measured RMS 
values ranging from 162-174 dB and peak SPLs from 172 to 186 dB. SEL 
measurements were not recorded. From Pier 40, NMFS selected a RMS value 
of 171 decibel (dB), which was the average of the eight piles tested, 
excluding two piles that utilized ``jetting.'' Jetting consists of 
employing a carefully directed and pressurized flow of water to assist 
in pile placement by liquefying soils at the pile tip during pile 
placement. Jetting tends to increase driving efficiency while 
decreasing sound levels and will not be utilized by Chevron during this 
project. Note that NMFS had incorrectly used a RMS value of 170 dB in 
the Notice of Proposed IHA. Utilizing the corrected value of 171 dB 
results in slightly larger predicted Level A and Level B isopleths. 
NMFS used an identical approach to arrive at an average peak value of 
181 dB based on results from Pier 40.
    Sound Propagation--Transmission loss (TL) is the decrease in 
acoustic intensity as an acoustic pressure wave propagates out from a 
source. TL parameters vary with frequency, temperature, sea conditions, 
current, source and receiver depth, water depth, water chemistry, and 
bottom composition and topography. The general formula for underwater 
TL is:

TL = B * log10 (R1/R2),

Where:

R1 = the distance of the modeled SPL from the driven pile, and
R2 = the distance from the driven pile of the initial measurement.
B = spreading loss value

    This formula does not account for loss due to scattering and 
absorption, which is assumed to be zero here. The degree to which 
underwater sound propagates away from a sound source is dependent on a 
variety of factors, most notably the water bathymetry and presence or 
absence of reflective or absorptive conditions including in-water 
structures and sediments. Spherical spreading occurs in a perfectly 
unobstructed (free-field) environment not limited by depth or water 
surface, resulting in a 6 dB reduction in sound level for each doubling 
of distance from the source (20*log(range)). Cylindrical spreading 
occurs in an environment in which sound propagation is bounded by the 
water surface and sea bottom, resulting in a reduction of 3 dB in sound 
level for each doubling of distance from the source (10*log(range)). As 
is common practice in coastal waters, here we assume practical 
spreading loss (4.5 dB reduction in sound level for each doubling of 
distance) here. Practical spreading is a compromise that is often used 
under conditions where water increases with depth as the receiver moves 
away from the shoreline, resulting in an expected propagation 
environment that would lie between spherical and cylindrical spreading 
loss conditions.
    Level A Zone--Chevron's Level A harassment zone was calculated by 
utilizing the methods presented in Appendix D of NMFS' Guidance and the 
accompanying User Spreadsheet. The Guidance provides updated PTS onset 
thresholds using the cumulative SEL (SELcum) metric, which 
incorporates marine mammal auditory weighting functions, to identify 
the received levels, or acoustic thresholds, at which individual marine 
mammals are predicted to experience changes in their hearing 
sensitivity for acute, incidental exposure to all underwater 
anthropogenic sound sources. The Guidance and its companion User 
Spreadsheet provide alternative methodology for incorporating these 
more complex thresholds and associated weighting functions.
    The User Spreadsheet accounts for weighting functions using 
Weighting Factor Adjustments (WFAs), and NMFS used the recommended 
values for impact driving therein (2 kilohertz (kHz)). Pile driving 
durations were estimated based on similar project experience. NMFS' new 
acoustic thresholds use dual metrics of SELcum and peak sound level 
(PK) for impulsive sounds (e.g., impact pile driving). The noise levels 
noted above were used in the Spreadsheet for 24-inch square concrete 
piles. It was estimated that two piles would be installed in one 24-hr 
workday with installation for each pile requiring approximately 300 
blows. NMFS used an RMS of 171 dB and pulse duration of 0.1 seconds. 
Measured SEL values were not available for 24-inch square concrete 
piles.
    Utilizing the User Spreadsheet, NMFS applied the updated PTS onset 
thresholds for impulsive PK and SELcum in the new acoustic guidance to 
determine distance to the isopleths for PTS onset for impact pile 
driving. In determining the cumulative sound exposure levels, the 
Guidance considers the duration of the activity, the sound exposure 
level produced by the source during a 24-hr period, and the generalized 
hearing range of the receiving species. In the case of the duel metric 
acoustic thresholds for impulsive sound, the larger of the two 
isopleths for calculating PTS onset is used. Results in Table 4 display 
the Level A injury zones for the various hearing groups.

[[Page 27246]]



          Table 4--Injury Zones and Shutdown Zones For Hearing Groups Associated With Installation of 24-Inch Concrete Piles Via Impact Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Low-frequency                                  High-frequency
           Hearing group                cetaceans  (gray          Mid-frequency        cetaceans  (harbor      Phocid pinnipeds      Otariid pinnipeds
                                             whale)                 cetaceans              porpoise)            (harbor seal)          (CA sea lion)
--------------------------------------------------------------------------------------------------------------------------------------------------------
PTS Onset Acoustic Thresholds--      Lpk,flat: 219 dB......  Lpk,flat: 230 dB......  Lpk,flat: 202 dB.....  Lpk,flat: 218 dB.....  Lpk,flat: 232 dB
 Impulsive *.                        LE,LF,24h: 183 dB.....  LE,MF,24h: 185 dB.....  LE,HF,24h: 155 dB....  LE,PW,24h: 185 dB....  LE,OW,24h: 203 dB
(Received Level)...................
PTS Isopleth to threshold (m)......  24.3..................  0.9...................  28.9.................  13.0.................  0.9
--------------------------------------------------------------------------------------------------------------------------------------------------------
* 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.

    The zone of influence (ZOI) refers to the area(s) in which SPLs 
equal or exceed NMFS' current Level B harassment thresholds (160 dB for 
impulse sound). Calculated radial distances to the 160 dB threshold 
assume a field free of obstruction. Assuming a source level of 171 dB 
RMS, installation of the 24-inch concrete piles is expected to produce 
underwater sound exceeding the Level B 160 dB RMS threshold over a 
distance of 54 meters (177 feet) (Table 5).

        Table 5--Isopleth for Level B harassment associated with impact driving of 24-inch concrete piles
----------------------------------------------------------------------------------------------------------------
                                                                                                     Isopleth
               Criterion                         Definition                   Threshold           (distance from
                                                                                                     source)
----------------------------------------------------------------------------------------------------------------
Level B harassment.....................  Behavioral disruption.....  160 dB RMS................             54m
                                                                     (impulse sources).........
----------------------------------------------------------------------------------------------------------------

    Density/Abundance--Data specifying a marine mammal's density or 
abundance in a given area can often be used to generate exposure 
estimates. However, no systematic line transect surveys of marine 
mammals have been performed in the San Francisco Bay near the project 
site. Density information for marine mammal species has been generated 
by Caltrans based on 15 years (2000-2015) of observations as part of 
the San Francisco-Oakland Bay Bridge replacement project (Caltrans 
2016). The data revealed densities of 0.00004 animals/kilometer (km\2\ 
for gray whale, 0.021 animals/km\2\ for harbor porpoise, 0.09 animals/
km\2\ for California sea lion, and 0.17 animals/km\2\ for harbor seal. 
Utilization of these data to develop exposure estimates results in very 
small exposure values. Despite the near zero estimate provided through 
use of the Caltrans density data, local observational data led us to 
believe that this estimate may not be accurate in illustrating the 
potential for take at this particular site, so we have to use other 
information. Instead, NMFS relied on local observational data as 
described below.
    Take Estimate--The estimated number of marine mammals that may be 
exposed to noise at levels expected to result in take as defined in the 
MMPA is determined by comparing the calculated areas over which the 
Level B harassment threshold may be exceeded, as described above, with 
the expected distribution of marine mammal species within the vicinity 
of the project. NMFS calculated take qualitatively utilizing 
observational data taken during marine mammal monitoring associated 
with the RSRB retrofit project, the San Francisco-Oakland Bay Bridge 
replacement project, and other marine mammal observations for San 
Francisco Bay. As described previously in the Effects section, Level B 
Harassment is expected to occur and is authorized in the numbers 
identified below.

Pacific Harbor Seal

    Castro Rocks 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). The pupping season is from March 
to June in San Francisco Bay. During the molting season (typically 
June-July and coinciding with the period when piles will be driven) as 
many as 129 harbor seals have been observed using Castro Rocks as a 
haul out. Harbor seals are more likely to be hauled out in the late 
afternoon and evening, and are more likely to be in the water during 
the morning and early afternoon (Green et al., 2002). However, during 
the molting season, harbor seals spend more time hauled out and tend to 
enter the water later in the evening. During molting, harbor seals can 
stay onshore resting for an average of 12 hours per day during the molt 
compared to around 7 hours per day outside of the pupping/molting 
seasons (NPS 2014).
    Tidal stage is a major controlling factor of 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. The 
take estimates are based on the

[[Page 27247]]

highest number of harbor seals observed at Castro Rocks during 2007 to 
2012 annual surveys (approximately 129 seals). Without site-specific 
data, it is impossible to determine how many hauled out seals enter the 
water and, of those, how many enter into the Level B harassment area. 
Given the relatively small size of the Level B harassment area compared 
to the large expanse of Bay water that is available to the seals, NMFS 
will assume that no more than 6 seals per day would enter into the 
Level B harassment area during the 40 minutes of pile driving per day 
scheduled to occur over 4 days. Therefore, NMFS authorizes Level B take 
of up to 6 seals per day may over 4 days of impact driving, resulting 
in a total of 24 authorized incidents of take.

California Sea Lion

    Relatively few California sea lions are expected to be present in 
the project area during periods of pile driving, as there are no haul-
outs utilized by this species in the vicinity. However, monitoring for 
the RSRB did observe small numbers of this species in the north and 
central portions of the Bay during working hours. During monitoring 
that occurred over a period of May 1998 to February 2002, California 
sea lions were sighted at least 90 times in the northern portion of the 
Central Bay and at least 57 times near the San Francisco-Oakland Bay 
Bridge in the Central Bay. During monitoring for the San Francisco-
Oakland Bay Bridge Project in the Central Bay, California sea lions 
were observed on 69 occasions in the vicinity of the bridge over a 14-
year period from 2000-2014 (Caltrans 2015b). The limited data regarding 
these observations do not allow a quantitative assessment of potential 
take. Given the limited driving time, low number of sea lions that are 
likely to be found in the northern part of the Bay, and small size of 
the level B zone, NMFS is authorizing a total of two incidents of take 
for California sea lions.

Harbor Porpoise

    A small but growing population of harbor porpoises utilizes San 
Francisco Bay. Harbor porpoises are typically spotted in the vicinity 
of Angel Island and the Golden Gate Bridge (6 and 12 km southwest 
respectively) (Keener 2011), but may utilize other areas in the Central 
Bay in low numbers, including the project area. The density and 
frequency of this usage throughout the Bay is unknown. For this IHA, 
NMFS is not authorizing take of any harbor porpoise since the exclusion 
zone will be conservatively set at 55 m, which is larger than the Level 
B zone isopleth of 54 m, and take can be avoided.

Gray Whale

    The only whale species that enters San Francisco bay with any 
regularity is the gray whale. Gray whales occasionally enter the Bay 
during their northward migration period, and are most often sighted in 
the Bay between February and May. Most venture only about 2 to 3 km 
past the Golden Gate Bridge, but gray whales have occasionally been 
sighted as far north as San Pablo Bay. Impact pile driving is not 
expected to occur during this time, however, and gray whales are not 
likely to be present at other times of year. Furthermore, the exclusion 
zone of 55 m for this species is larger than the Level B zone isopleth 
of 54 m. As such, NMFS is not authorizing any gray whale take.
    Table 6 shows estimated Level B take for authorized species.

                       Table 6--Summary of Estimated Take by Species (Level B Harassment)
----------------------------------------------------------------------------------------------------------------
                                                                                              Species
           Pile type            Pile driver type     Number of       Number of   -------------------------------
                                                       piles       driving days     Harbor seal     CA sea lion
----------------------------------------------------------------------------------------------------------------
24-inch square concrete.......  Impact..........               8               4              24               2
----------------------------------------------------------------------------------------------------------------

Mitigation

    Under section 101(a)(5)(D) of the MMPA, NMFS shall prescribe the 
permissible methods of taking by harassment 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 subsistence uses.
    To ensure that the ``least practicable impact'' will be achieved, 
NMFS evaluates mitigation measures in consideration of the following 
factors in relation to one another:
     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, their 
habitat; and
     their availability for subsistence uses (latter where 
relevant); the proven or likely efficacy of the measures; and the 
practicability of the measures for applicant implementation.

Mitigation for Mammals and Their Habitat

    The following measures would apply to Chevron's mitigation through 
the exclusion zone and zone of influence (ZOI):
    Time Restriction--For all in-water pile driving activities, Chevron 
shall operate only during daylight hours when visual monitoring of 
marine mammals can be conducted.
    Seasonal Restriction--To minimize impacts to listed fish species, 
pile-driving activities would occur between June 1 and November 30.
    Exclusion Zone--For all pile driving activities, Chevron will 
establish an exclusion zone intended to contain the area in which Level 
A harassment thresholds are exceeded. The purpose of the exclusion zone 
is to define an area within which shutdown of construction activity 
would occur upon sighting of a marine mammal within that area (or in 
anticipation of an animal entering the defined area), thus preventing 
potential injury of marine mammals. The calculated distance to Level A 
harassment isopleths threshold during impact pile driving, assuming a 
maximum of 2 piles per day is 28.9 m for harbor porpoise; 13.0 m for 
harbor seal; 0.9 m for California sea lion, and; 24.3 m for gray 
whales.
    NMFS will require a 15 m exclusion zone for harbor seals and 
California sea lions. In order to prevent any take of the cetacean 
species, a 55 m exclusion zone will be required for harbor porpoises 
and gray whales, which exceeds the Level B harassment isopleth. A 
shutdown will occur prior to a marine mammal entering the shutdown 
zones. Activity will cease until the observer is confident that the 
animal is clear of the shutdown zone. The animal will be considered 
clear if:
     It has been observed leaving the shutdown zone; or
     It has not been seen in the shutdown zone for 30 minutes 
for cetaceans and 15 minutes for pinnipeds.
    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

[[Page 27248]]

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.
    Level B Harassment Zone (Zone of Influence)--The ZOI refers to the 
area(s) in which SPLs equal or exceed NMFS' current Level B harassment 
thresholds (160 dB rms for pulse sources). ZOIs provide utility for 
monitoring that is conducted for mitigation purposes (i.e., exclusion 
zone monitoring) by establishing monitoring protocols for areas 
adjacent to the exclusion zone. Monitoring of the ZOI enables observers 
to be aware of, and communicate about, the presence of marine mammals 
within the project area but outside the exclusion zone and thus prepare 
for potential shutdowns of activity should those marine mammals 
approach the exclusion zone. However, the primary purpose of ZOI 
monitoring is to allow documentation of incidents of Level B 
harassment; ZOI monitoring is discussed in greater detail later (see 
Monitoring and Reporting). The modeled radial distances for the ZOI for 
impact pile driving of 24-inch square concrete piles is 54 m. NMFS will 
require a 55 m Level B zone for harbor seals and California sea lions.
    In order to document observed incidents of harassment, monitors 
will record all marine mammals observed within the ZOI. Due to the 
relatively small ZOI and to the monitoring locations chosen by Chevron 
we expect that two monitors will be able to observe the entire ZOI.
    The shutdown zone and ZOI shall be monitored throughout the time 
required to install a pile. If a harbor seal or California sea lion is 
observed entering the ZOI, a Level B exposure shall be recorded and 
behaviors documented. That pile segment shall be completed without 
cessation, unless the animal approaches the shutdown zone. Pile 
installation shall be halted immediately before the animal enters the 
Level A zone.
    If any marine mammal species other than those for which take is 
authorized, or if a species for which authorization has been granted 
but the number of authorized takes has been met enters or approaches 
the ZOI, all activities shall be shut down until the animal is observed 
leaving the ZOI or it has not been observed in the ZOI for 30 minutes 
for cetaceans and 15 minutes for pinnipeds.
    Ramp up/Soft-Start--A ``soft-start'' technique is intended to allow 
marine mammals to vacate the area before the pile driver reaches full 
power. For impact driving, an initial set of three strikes would be 
made by the hammer at reduced energy, followed by a 30-sec waiting 
period, then two subsequent three- strike sets before initiating 
continuous driving. Soft start will be required at the beginning of 
each day's impact pile driving work and at any time following a 
cessation of impact pile driving of thirty minutes or longer.
    If a marine mammal is present within a shutdown zone, ramping up 
shall be delayed until the animal(s) leaves the relevant shutdown zone. 
Activity shall begin only after the MMO has determined, through 
sighting, that the animal(s) has moved outside the relevant shutdown 
zone or it has not been observed in the shutdown zone for 30 minutes 
for cetaceans and 15 minutes for pinnipeds.
    If an authorized species is present in the Level B harassment zone, 
ramping up shall begin and a Level B take shall be documented. Ramping 
up shall occur when these species are in the Level B harassment zone 
whether they entered the Level B zone from the Level A zone, or from 
outside the project area.
    Pile Caps/Cushions--Chevron will employ the use of pile caps or 
cushions as sound attenuation devices to reduce impacts from sound 
exposure during impact pile driving.
    Based on our evaluation of the applicant's measures, as well as 
other measures considered by NMFS, we have determined that the required 
mitigation measures provide the means effecting the least practicable 
impact on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, Section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth, requirements pertaining to 
the monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
action area. Effective reporting is critical both to compliance as well 
as ensuring that the most value is obtained from the required 
monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the 
action area (e.g., presence, abundance, distribution, density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.
    Chevron will collect sighting data and will record behavioral 
responses to construction activities for marine mammal species observed 
in the project location during the period of activity. Monitoring will 
be conducted by qualified marine mammal observers (MMO), who are 
trained biologists, with the following minimum qualifications:
     Independent observers (i.e., not construction personnel) 
are required;
     At least one observer must have prior experience working 
as an observer;
     Other observers may substitute education (undergraduate 
degree in biological science or related field) or training for 
experience;
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and

[[Page 27249]]

times when in-water construction activities were conducted; dates and 
times when in-water construction activities were suspended to avoid 
potential incidental injury from construction sound of marine mammals 
observed within a defined shutdown zone; and marine mammal behavior;
     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; and
     NMFS will require submission and approval of observer CVs.
    Chevron will monitor the exclusion zones and Level B harassment 
zone before, during, and after pile driving, with at least two 
observers located at the best practicable vantage points. Based on our 
requirements, the Marine Mammal Monitoring Plan would implement the 
following procedures for pile driving:
     During observation periods, observers will continuously 
scan the area for marine mammals using binoculars and the naked eye;
     Monitoring shall begin 30 minutes prior to impact pile 
driving;
     Observers will conduct observations, meet training 
requirements, fill out data forms, and report findings in accordance 
with this IHA;
     If the exclusion zone is obscured by fog or poor lighting 
conditions, pile driving will not be initiated until the exclusion zone 
is clearly visible. Should such conditions arise while impact driving 
is underway, the activity would be halted;
     Observers will be in continuous contact with the 
construction personnel via two-way radio. A cellular phone will be used 
for back-up communications and for safety purposes;
     Observers will implement mitigation measures including 
monitoring of the shutdown and monitoring zones, clearing of the zones, 
and shutdown procedures; and
     At the end of the pile-driving day, post-construction 
monitoring will be conducted for 30 minutes beyond the cessation of 
pile driving.

Sound Source Verification

    Sound Source Verification (SSV) testing of impact driving will be 
conducted under this IHA. Little data exist for source levels 
associated with installation of 24-in square concrete piles (including 
data on single strike sound exposure level metrics). Chevron will 
conduct in-situ measurements during installation of four out of eight 
piles. The SSV will be conducted by an acoustical firm with prior 
experience conducting SSV tests. NMFS must approve the acoustic 
monitoring plan. Final results will be sent to NMFS. Findings will be 
used to establish Level A and Level B isopleths during impact driving 
of 24-in square concrete piles for future IHA's associated with this 
project.

Data Collection

    We require that observers use approved data forms. Among other 
pieces of information, chevron will record detailed information about 
any implementation of shutdowns, including the distance of animals to 
the pile being driven, a description of specific actions that ensued, 
and resulting behavior of the animal, if any. In addition, Chevron will 
attempt to distinguish between the number of individual animals taken 
and the number of incidents of take, when possible. We require that, at 
a minimum, that the following information be recorded on sighting 
forms:
     Date and time that permitted construction activity begins 
or ends;
     Weather parameters (e.g., percent cloud cover, percent 
glare, visibility) and Beaufort sea state;
     Species, numbers, and, if possible, sex and age class of 
observed marine mammals;
     Construction activities occurring during each sighting;
     Marine mammal behavior patterns observed, including 
bearing and direction of travel;
     Specific focus should be paid to behavioral reactions just 
prior to, or during, soft-start and shutdown procedures;
     Location of marine mammal, distance from observer to the 
marine mammal, and distance from pile driving activities to marine 
mammals;
     Record of whether an observation required the 
implementation of mitigation measures, including shutdown procedures 
and the duration of each shutdown; and
     Other human activity in the area. Record the hull numbers 
of fishing vessels if possible.

Reporting Measures

    Chevron shall submit a draft report to NMFS within 90 days of the 
completion of marine mammal monitoring, or 60 days prior to the 
issuance of any subsequent IHA for this project (if required), 
whichever comes first. The annual report would detail the monitoring 
protocol, summarize the data recorded during monitoring, and estimate 
the number of marine mammals that may have been harassed. If no 
comments are received from NMFS within 30 days, the draft final report 
will become final. If comments are received, a final report must be 
submitted up to 30 days after receipt of comments. Reports shall 
contain the following information:
     Summaries of monitoring effort (e.g., total hours, total 
distances, and marine mammal distribution through the study period, 
accounting for sea state and other factors affecting visibility and 
detectability of marine mammals);
     Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare); and
     Species composition, occurrence, and distribution of 
marine mammal sightings, including date, numbers, age/size/gender 
categories (if determinable), and group sizes.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA 
(if issued), such as an injury (Level A harassment), serious injury or 
mortality (e.g., ship-strike, gear interaction, and/or entanglement), 
Chevron would immediately cease the specified activities and 
immediately report the incident to the Office of Protected Resources, 
NMFS, and the West Coast Regional Stranding Coordinator. The report 
would include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved (if applicable);
     Vessel's speed during and leading up to the incident (if 
applicable);
     Description of the incident;
     Status of all sound source used in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and 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 necessary actions 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.

[[Page 27250]]

    In the event that Chevron discovers an injured or dead marine 
mammal, and the lead MMO determines that the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition as described in the next paragraph), 
Chevron would immediately report the incident to the Office of 
Protected Resources, NMFS, and the West Coast Regional Stranding 
Coordinator. The report would include the same information identified 
in the section 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 MMO 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 Office of Protected Resources, NMFS, and West Coast Regional 
Stranding Coordinator, within 24 hours of the discovery. Chevron would 
provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network. Pile driving activities would be permitted to 
continue.

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 the authorized 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, etc.), as well as effects on habitat, the status of the 
affected stocks, and the likely effectiveness of the mitigation. 
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 these analyses 
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).
    To avoid repetition, this introductory discussion of our analyses 
applies to all the species listed in Table 7 given that the anticipated 
effects of Chevron's construction activities involving impact pile 
driving on marine mammals are expected to be relatively similar in 
nature. There is no information about the nature or severity of the 
impacts, or the size, status, or structure of any species or stock that 
would lead to a different analysis for this activity, or else species-
specific factors would be identified and analyzed.
    Impact pile driving activities associated with the project, as 
outlined previously, have the potential to disturb or displace marine 
mammals. Specifically, the specified activities may result in take, in 
the form of Level B harassment (behavioral disturbance), from 
underwater sounds generated from pile driving. Potential takes could 
occur if individuals of these species are present in the ensonified 
zone when in-water construction is under way.
    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 injuries or mortalities are 
anticipated to occur as a result of Chevron's impact pile driving 
activities. The relatively low marine mammal density and small shutdown 
zones make injury takes of marine mammals unlikely. In addition, the 
Level A exclusion zones would be thoroughly monitored before the impact 
pile driving occurs and driving activities would be would be postponed 
if a marine mammal is sighted entering the exclusion zones. The 
likelihood that marine mammals will be detected by trained observers is 
high under the environmental conditions described for the project. The 
employment of the soft-start mitigation measure would also allow marine 
mammal in or near the ZOI or exclusion zone to move away from the 
impact driving sound source. Therefore, the mitigation and monitoring 
measures are expected to eliminate the potential for injury and reduce 
the amount and intensity of behavioral harassment. Furthermore, the 
pile driving activities analyzed here are similar to, or less impactful 
than, numerous construction activities conducted in 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.
    The takes that are anticipated and authorized are expected to be 
limited to short-term Level B harassment (behavioral) as only eight 
piles will be driven over 4 days with each pile requiring approximately 
20 minutes of driving time. Marine mammals present near the action area 
and taken by Level B harassment would most likely show overt brief 
disturbance (e.g. startle reaction) and avoidance of the area from 
elevated noise level during pile driving. Repeated exposures of 
individuals to levels of sound that may cause Level B harassment are 
unlikely to significantly disrupt foraging behavior. Thus, even 
repeated Level B harassment of some small subset of the overall stock 
is unlikely to result in any significant realized decrease in fitness 
for the affected individuals, and thus would not result in any adverse 
impact to the stock as a whole.
    The project is not expected to have significant adverse effects on 
affected marine mammals' habitat. While EFH for several species does 
exist in the project area, the activities would not permanently modify 
existing marine mammal habitat. The activities may cause fish to leave 
the area temporarily. This could impact marine mammals' foraging 
opportunities in a limited portion of the foraging range; but, because 
of the short duration of the activities and the relatively small area 
of affected habitat, the impacts to marine mammal habitat are not 
expected to cause significant or long-term negative consequences.
    In summary, this negligible impact analysis is founded on the 
following factors: (1) The possibility of non-auditory injury, serious 
injury, or mortality may reasonably be considered discountable; (2) the 
anticipated incidents of Level B harassment consist of, at worst, 
temporary modifications in behavior; (3) the short duration of in-water 
construction activities (4 days, 160 minutes total driving time); (4) 
limited spatial impacts to marine mammal habitat; and (5) the presumed 
efficacy of the mitigation measures in reducing the effects of the 
specified activity to the level of least practicable impact. In 
combination, we believe that these factors, as well as the available 
body of evidence from other similar activities, demonstrate that the 
potential effects of the specified activity will have only short-term 
effects on individuals.

[[Page 27251]]

The specified activity is not expected to impact rates of recruitment 
or survival and will therefore not result in population-level impacts.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
activity will have a negligible impact on all affected marine mammal 
species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Section 101(a)(5)(D) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers and so, in practice, NMFS compares the number of 
individuals taken to the most appropriate estimation of the relevant 
species or stock size in our determination of whether an authorization 
is limited to small numbers of marine mammals.
    The numbers of animals authorized to be taken would be considered 
small relative to the relevant stocks or populations (<0.01 percent for 
both species as shown in Table 7) even if each estimated taking 
occurred to a new individual. However, the likelihood that each take 
would occur to a new individual is extremely low. Further, these takes 
are likely to occur only within some small portion of the overall 
regional stock.

Table 7--Population Abundance Estimates, Total Authorized Level B Take, and Percentage of Population That May Be
                          Taken for the Potentially Affected Species During the Project
----------------------------------------------------------------------------------------------------------------
                                                                                                   Percentage of
                             Species                                Abundance*     Total level B     stock or
                                                                                       take         population
----------------------------------------------------------------------------------------------------------------
Harbor seal.....................................................      \1\ 30,968              24           <0.01
California sea lion (U.S. Stock)................................         296,750               2           <0.01
----------------------------------------------------------------------------------------------------------------
* Abundance estimates are taken from the 2015 U.S. Pacific Marine Mammal Stock Assessments (Carretta et al.,
  2016).
\1\ California stock abundance estimate.

    Based on the analysis contained herein of the activity (including 
the mitigation and monitoring measures) and the anticipated take of 
marine mammals, NMFS finds that small numbers of marine mammals 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)

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

National Environmental Policy Act (NEPA)

    Issuance of an MMPA authorization requires compliance with NEPA. 
NMFS has established categorical exclusion (CE) status under NEPA for 
this action. As such, we have determined the issuance of the IHA is 
consistent with categories of activities identified in CE B4 of the 
Companion Manual for NAO 216-6A and we have not identified any 
extraordinary circumstances listed in Chapter 4 of the Companion Manual 
for NAO 216-6A that would preclude this categorical exclusion. NMFS has 
prepared a CE memorandum for the record.

Authorization

    As a result of these determinations, NMFS has issued an IHA to 
Chevron for the harassment of small numbers of harbor seals and 
California sea lions incidental to the Richmond Refinery Long Wharf 
Maintenance and Efficiency Project in San Francisco Bay, California 
effective for one year beginning January 1, 2018, provided the 
previously mentioned mitigation, monitoring and reporting requirements 
are incorporated.

    Dated: June 9, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2017-12295 Filed 6-13-17; 8:45 am]
 BILLING CODE 3510-22-P