[Federal Register Volume 83, Number 204 (Monday, October 22, 2018)]
[Notices]
[Pages 53217-53231]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-22923]


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

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XG105


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to the Mission Bay Ferry and Water 
Taxi Landing Project in San Francisco Bay, California

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

ACTION: Notice; issuance of incidental harassment authorization.

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

SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
the Port of San Francisco to incidentally harass, by Level B harassment 
only, marine mammals during construction activities associated with the 
pile driving, pile removal, and drilling on the Mission Bay Ferry 
Landing (MBFL) and Water Taxi Landing (WTL) Project in San Francisco 
Bay, California.

DATES: This Authorization is effective from June 1, 2019, to May 31, 
2020.

FOR FURTHER INFORMATION CONTACT: Gray Redding, 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/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. 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 an 
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. The definitions 
of all applicable MMPA statutory terms cited above are included in the 
relevant sections below.

Summary of Request

    On November 2, 2017, NMFS received a request from the Port of San 
Francisco for an IHA to take marine mammals incidental to pile driving 
and drilling in San Francisco Bay. NMFS determined that a revised 
version of the Port's application was adequate and complete on June 22, 
2018. The Port of San Francisco's request was for take of seven species 
of marine mammals by Level B harassment only. This authorization is 
valid from June 1, 2019, to May 31, 2020. Neither the Port of San 
Francisco nor NMFS expects serious injury or mortality to result from 
this activity and, therefore, an IHA is appropriate.

Description of Proposed Activity

Overview

    The Port of San Francisco plans to construct the MBFL and WTL on 
San Francisco Bay, within the Port of San Francisco's Southern 
Waterfront in the Mission Bay/Central Waterfront area. The project will 
create two, two-berth, floating landings to add ferry and water taxi 
access to the area. The project's activities that have the potential to 
take marine mammals include vibratory and impact pile driving, 
vibratory pile removal, and down the hole drilling. In total, 28 
permanent piles ranging from 16-inch to 36-inch in diameter will be 
installed, but only 24 will require in water installation. Twelve older 
piles will be removed, and four 14-inch H-piles and one 30-inch steel 
pile will be driven temporally to act as the caisson and supports 
during down the hole drilling at 10 locations. In addition, the project 
will include dredging, however authorization of take from this activity 
is neither requested nor proposed for authorization. All piles will be 
driven between June 1, 2019 and November 20, 2019.
    A detailed description of the planned Port of San Francisco MBFL 
and WTL project is provided in the Federal Register notice for the 
proposed IHA (83 FR 42465; August 22, 2018). Since that time, no 
changes have been made to the planned Port of San Francisco activities. 
Therefore, a detailed description is not provided here. Please refer to 
that Federal Register notice for the description of the specific 
activity.
    While there were not changes to the planned activity, some errors 
were corrected and other minor changes occurred following publication 
of the proposed IHA. These changes are outlined in each section of this 
notice In this section, the rate of pile installation for 36-inch steel 
piles was corrected from 5 piles per day to 4, to address an 
inconsistency in the application and more accurately reflect the 
applicant's expected schedule.

[[Page 53218]]



                                                     Table 1--Summary of In Water Pile Installation
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                       Pile
      Locations             Project  element         diameter            Pile type           Number of           Method          Piles/day  Construction
                                                      (inch)                                    piles                                            days
--------------------------------------------------------------------------------------------------------------------------------------------------------
                  Debris Removal                           12  Steel.......................         12  If necessary, a                 12             1
                                                                                                         vibratory hammer will
                                                                                                         be used to remove up
                                                                                                         to 12 piles
                                                                                                         60[hyphen]120 seconds/
                                                                                                         pile while pulling the
                                                                                                         pile up to loosen it
                                                                                                         from the sediment.
---------------------------------------------------
MBFL................  Pier........................         14  H-pile steel................          4  Four 14-inch steel H             4            10
                                                           30  Steel Caisson...............          1   beams will be driven            1
                                                           24  Octagonal Concrete..........         10   with Vibratory Driver           1
                                                                                                         600 seconds/pile to
                                                                                                         support 30[hyphen]inch
                                                                                                         steel caisson sleeve
                                                                                                         driven with Vibratory
                                                                                                         Driver (900 sec/pile)
                                                                                                         to refusal, drill out
                                                                                                         hole removing soils,
                                                                                                         place and position
                                                                                                         concrete pile, grout
                                                                                                         pile in place while
                                                                                                         simultaneously pulling
                                                                                                         the caisson.
                      Float Guide Piles...........         36  Steel.......................          6  Vibratory Driver 1,200           4             2
                                                                                                         sec/pile then Impact
                                                                                                         Hammer last 15 ft (150
                                                                                                         strikes/pile ~20
                                                                                                         minutes); bubble
                                                                                                         curtain will be used
                                                                                                         during impact duration.
                      Donut Fender Piles..........         36  Steel.......................          2  Vibratory Driver 1200            4
                                                                                                         sec/pile then Impact
                                                                                                         Hammer last 15 ft (150
                                                                                                         strikes/pile ~20
                                                                                                         minutes); bubble
                                                                                                         curtain will be used
                                                                                                         during impact duration.
WTL.................  Platform....................         16  Steel.......................          2  Vibratory Driver 600             2             1
                                                                                                         sec/pile then Impact
                                                                                                         Hammer last 15 ft (500
                                                                                                         strikes/pile ~20
                                                                                                         minutes); bubble
                                                                                                         curtain will be used
                                                                                                         during impact duration.
                      Guide Piles.................         20  Square Concrete.............          4  Impact Hammer 500                4             1
                                                                                                         strikes/pile (max 20
                                                                                                         minutes); a bubble
                                                                                                         curtain will be used
                                                                                                         during impact duration.
--------------------------------------------------------------------------------------------------------------------------------------------------------

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to the Port of San 
Francisco was published in the Federal Register on August 22, 2018 (83 
FR 42465). That notice described, in detail, the Port of San 
Francisco'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 IHA, subject to inclusion of the proposed mitigation, 
monitoring, and reporting measures.
    Comment 1: The Commission recommended NMFS authorize take by Level 
A harassment for harbor seals, noting the estimated number that could 
occur in the Level A harassment zone, the potential for take, and the 
possible limited effectiveness of mitigation.
    Response 1: NMFS recognizes the potential for Level A harassment 
associated with the Port of San Francisco's MBFL and WTL project, but 
notes that this anticipated take by Level A harassment of two harbor 
seals is avoidable given the required mitigation and monitoring. 
Additionally, this calculation is highly conservative because it uses 
the project's largest Level A harassment zone for the entire duration, 
despite this zone being in effect for a short time and other Level A 
harassment zones being smaller. While NMFS could authorize take by 
Level A harassment associated with this activity as a precaution, we do 
not agree that such authorization is warranted and the applicant did 
not request such authorization. Additionally, the observation of an 
animal within the Level A harassment zone does not necessarily equate 
to an incident of Level A harassment, as the calculation of that zone 
assumes that the animal is present at that distance from the driven 
pile for a given duration necessary to accumulate sufficient sound 
energy to actually incur injury. The largest Level A harassment zone 
for harbor seals, of 130 meters (m), assumes an activity duration of 40 
minutes. Given that, it is unlikely that briefly occupying the Level A 
harassment zone would expose an animal to sound energy sufficient to 
cause take by Level A harassment.
    Comment 2: The Commission recommended that NMFS refrain from using 
a source level reduction factor for sound attenuation device 
implementation during impact pile driving for all relevant incidental 
take authorizations due to the different noise level reduction at 
different received ranges.
    Response 2: While it is true that noise level reduction measured at 
different received ranges does vary, given that both Level A and Level 
B harassment estimation using geometric modeling is based on noise 
levels measured at near-source distances (~10 m), NMFS believes it 
reasonable to use a source level reduction factor for sound attenuation 
device implementation during impact pile driving. In the case of the 
SF-OBB impact driving isopleth estimates using an air bubble curtain 
for source level reduction, NMFS reviewed Caltrans' bubble curtain ``on 
and off'' studies conducted in San Francisco Bay in 2003 and 2004. The 
equipment used for bubble curtains has likely improved since 2004 but 
due to concerns for fish species, Caltrans has not been able to conduct 
``on and off'' tests recently. Based on 74 measurements (37 with the 
bubble curtain on and 37 with the bubble curtain off) at both near 
(<100 m) and far (>100 m) distances, the linear averaged received level 
reduction is 6 decibels (dB). If limiting the data points (a total of 
28 measurements, with 14 during bubble curtain on and 14 during bubble 
curtain off) to only near distance measurements, the linear averaged 
noise level reduction is 7 dB. Since impact zone analysis using 
geometric spreading model is typically based on measurements at near-
source distance, we consider it appropriate to use a reduction of 7 dB 
as a noise level reduction factor for impact pile driving using an air 
bubble curtain system.
    Bubble curtains are effective at attenuating sound originating 
within the water column. Pile driving does generate sound within the 
seafloor as well. This sound travels within the seafloor and emerges 
back to the water column, but its intensity is reduced within the 
sediment due to absorption by the sediment and reflection at the 
sediment/water interface.
    NMFS will evaluate the appropriateness of using a certain source 
level reduction factor for sound attenuation device implementation 
during impact pile driving for all relevant incidental take 
authorizations when more data become available.
    Comment 3: The Commission recommended that NMFS require the 
applicant to conduct sound source measurements of its drilling 
activities in conjunction with the required sound measurements of 
ambient conditions.
    Response 3: NMFS agrees that sound source measurements of the 
drilling

[[Page 53219]]

activities would be valuable, but has determined that this would be an 
overly burdensome requirement relative to the expected impacts of the 
specified activity (refer to negligible impact section). The project's 
permitted activity is short. Additionally, the process to record sound 
data sufficiently rigorous enough to provide new source information can 
be complex and costly. If the Port of San Francisco chooses to conduct 
sound source measurements, NMFS will work with the Port to help ensure 
these measurements are properly taken to best ensure their usefulness.
    Comment 4: The Commission recommends that NMFS require applicants 
to provide proposed hydroacoustic monitoring plans with their 
applications to allow for public comment, or provide them to the 
Commission for review prior to final authorization.
    Response 4: NMFS disagrees that the MMPA or NMFS's implementing 
regulations require that detailed hydroacoustic monitoring plans be 
made available for public review. Additionally, NMFS has the necessary 
technical expertise to properly evaluate and make recommendations to 
hydroacoustic monitoring plans that are received. That said, NMFS 
encourages applicants to prepare as detailed a monitoring plan as 
possible, as early in the process as possible, and shares these plans 
with the public if they are available at the time the proposed 
authorization is published.
    Comment 5: The Commission recommends that NMFS refrain from 
implementing its proposed renewal process and instead use abbreviated 
Federal Register notices and reference existing documents to streamline 
the incidental harassment authorization process. The Commission 
suggested that the MMPA states that public comment on proposed 
authorizations must be concurrent with publication in the Federal 
Register. The Commission further recommends that if NMFS did not pursue 
a more general route, NMFS provide the Commission and the public with a 
legal analysis supporting its conclusion that the process is consistent 
with the requirements under section 101(a)(5)(D) of the MMPA.
    Response 5: The notice of the proposed IHA expressly notifies the 
public that under certain, limited conditions an applicant could seek a 
renewal IHA for an additional year. The notice describes the conditions 
under which such a renewal request could be considered and expressly 
seeks public comment in the event such a renewal is sought. Additional 
reference to this solicitation of public comment has recently been 
added at the beginning of FR notices that consider renewals. NMFS 
appreciates the streamlining achieved by the use of abbreviated Federal 
Register notices and intends to continue using them for proposed IHAs 
that include minor changes from previously issued IHAs, but which do 
not satisfy the renewal requirements. However, we believe our proposed 
method for issuing renewals meets statutory requirements and maximizes 
efficiency. Importantly, such renewals would be limited to where the 
activities are identical or nearly identical to those analyzed in the 
proposed IHA, monitoring does not indicate impacts that were not 
previously analyzed and authorized, and the mitigation and monitoring 
requirements remain the same, all of which allow the public to comment 
on the appropriateness and effects of a renewal at the same time the 
public provides comments on the initial IHA. NMFS has, however, 
modified the language for future proposed IHAs to clarify that all 
IHAs, including renewal IHAs, are valid for no more than one year and 
that the agency would consider only one renewal for a project at this 
time. In addition, notice of issuance or denial of a renewal IHA would 
be published in the Federal Register, as are all IHAs. Last, NMFS will 
publish on our website a description of the renewal process before any 
renewal is issued utilizing the new process.

Description of Marine Mammals in the Area of Specified Activities

    A detailed description of the species likely to be affected by the 
Port of San Francisco's MBFL and WTL project, including brief 
introductions to the species and relevant stocks as well as available 
information regarding population trends and threats, and information 
regarding local occurrence, were provided in the Federal Register 
notice for the proposed IHA (83 FR 42465; August 22, 2018); 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' website (https://www.fisheries.noaa.gov/find-species) for generalized species accounts.
    Table 2 lists all species with expected potential for occurrence in 
the Mission Bay/Central Waterfront area of San Francisco Bay and 
summarizes information related to the population or stock, including 
regulatory status under the MMPA and ESA and potential biological 
removal (PBR), where known. For taxonomy, we follow the Committee on 
Taxonomy (2017). PBR is defined by the MMPA as the maximum number of 
animals, not including natural mortalities, that may be removed from a 
marine mammal stock while allowing that stock to reach or maintain its 
optimum sustainable population (as described in NMFS's Stock Assessment 
Report (SAR)). While NMFS neither anticipates nor proposes to authorize 
mortality here, PBR and annual serious injury and mortality from 
anthropogenic sources are included here as gross indicators of the 
status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS's stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. 2017 SAR (Carretta et al., 2017). All values presented in 
Table 2 are the most recent available at the time of publication and 
are available in the 2017 SAR (Carretta et al., 2017).

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

[[Page 53220]]

 
Family Balaenopteridae (rorquals):
    Humpback whale..................  Megaptera novaeangliae.  California/Oregon/       E/D; Y              1,918 (0.03, 1,876,            11       >6.5
                                                                Washington.                                  2014).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Bottlenose dolphin..............  Tursiops truncatus.....  California Coastal.....  -/-; N              453 (0.06, 346, 2011).        2.7         >2
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  San Francisco-Russian    -/-; N              9,886 (0.51, 6,625,            66          0
                                                                River.                                       2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    California sea lion.............  Zalophus californianus.  U.S....................  -/-; N              296,750 (n/a, 153,337,      9,200        389
                                                                                                             2011).
    Northern fur seal...............  Callorhinus ursinus....  California.............  -/-; N              14,050 (n/a, 7,524,           451        1.8
                                                                                                             2013).
                                                               Eastern North Pacific..  -/-; N              626,734 (n.a.,             11,405        1.1
                                                                                                             530,474, 2014).
    Guadalupe fur seal..............  Arctocephalus townsendi  Mexico to California...  T/D; Y              20,000 (n/a, 15,830,          542       >3.2
                                                                                                             2010).
Family Phocidae (earless seals):
    Pacific harbor seal.............  Phoca vitulina           California.............  -/-; N              30,968 (n/a, 27,348,        1,641         43
                                       richardii.                                                            2012).
    Northern elephant seal..........  Mirounga angustirostris  California Breeding....  -/-; N              179,000 (n/a, 81,368,       4,882        8.8
                                                                                                             2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.
Note: Italicized species are not expected to be taken or proposed for authorization.

    All species that could potentially occur in the Port's proposed 
project area in San Francisco Bay are included in Table 2. However, the 
temporal and/or spatial occurrence of humpback whale and Guadalupe fur 
seal is such that take is not expected to occur, and they are not 
discussed further beyond the explanation provided here. Humpback whales 
are rare visitors to the interior of San Francisco Bay. A recent, 
seasonal influx of humpback whales inside San Francisco Bay near the 
Golden Gate was recorded from April to November in 2016 and 2017 
(Keener 2017). The Golden Gate is outside of this project's action area 
and humpback whales are not expected to be present during the project. 
Guadalupe fur seals occasionally range into the waters of northern 
California and the Pacific Northwest. The Farallon Islands (off central 
California) and Channel Islands (off southern California) are used as 
haulouts during these movements (Simon 2016). Juvenile Guadalupe fur 
seals occasionally strand in the vicinity of San Francisco, especially 
during El Ni[ntilde]o events. Most strandings along the California 
coast are animals younger than two years old, with evidence of 
malnutrition (NMFS 2017a). Because Guadalupe fur seals are rare in the 
area, and sightings are associated with abnormal weather conditions, 
such as El Ni[ntilde]o events, NMFS has determined that no Guadalupe 
fur seals are likely to occur in the project vicinity and, therefore, 
no take is expected to occur.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from pile driving, pile removal, 
and drilling activities for the MBFL and WTL Project in San Francisco 
Bay, California 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 (83 FR 42465; August 22, 2018) 
included a discussion of the effects of anthropogenic noise on marine 
mammals, therefore that information is not repeated here; please refer 
to the Federal Register notice (83 FR 42465; August 22, 2018) for that 
information.

Anticipated Effects on Habitat

    The main impact associated with the Port of San Francisco's MBFL 
and WTL project would be temporarily elevated sound levels and the 
associated direct effects on marine mammals. 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 such as forage fish, and minor impacts to the 
immediate substrate during installation/removal of piles and drilling 
during the MBFL and WTL project. These potential effects are discussed 
in detail in the Federal Register notice for the proposed IHA (83 FR 
42465; August 22, 2018), therefore that information is not repeated 
here; please refer to that Federal Register notice for that 
information.

Estimated Take

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

[[Page 53221]]

    After public comment and review of the proposed authorization, the 
following items have changed in the final authorization.
    (1) The Level B harassment zone for drilling activities has 
decreased from 21,544 m to 15,849 m to account for an error that was 
present in the proposed IHA. During the drafting of the proposed IHA, 
the source level for drilling activities was reduced from 170 dB to 168 
dB based on proxy data from the Alaska Department of Transportation 
(2016). The resulting Level B harassment zone was not updated from 
21,544 m to 15,849 m until this error was noticed during public comment 
(Table 5).
    (2) The Level B harassment zone for impact driving of 16-inch steel 
piles changed from 215 m to 136 m to account for an error that was 
present in the proposed IHA. This change resulted in a corresponding 
correction the ensonified area (Table 5).
    (3) The Level B harassment zone for vibratory installation of 16-
inch steel pipe piles was reduced from 21,544 m to 3,415 m. This change 
was to correct a misstatement in the proposed IHA. The original Level B 
harassment zone was stated as 21,544 m, when 3,415 m was the correct 
value for the given source level (158 dB SPL). This source level 
remains at 158 dB as presented in the proposed IHA, and the Level B 
harassment zone has been updated to match this source level with a 
corresponding correction to the ensonified area (Table 5).
    (4) To correct errors present in the proposed IHA, duration 
estimates for some activities were updated. Updated activity durations 
included vibratory pile removal, vibratory pile installation of 36-inch 
steel piles, vibratory pile installation of 14-inch steel H piles, and 
down the hole drilling (Table 6). These changes were accompanied by 
corresponding but minor changes in Level A harassment zones (Table 7).
    (5) Errors in calculation of takes by Level B harassment for harbor 
seal, California sea lion, and harbor porpoise were corrected, 
resulting in decreased take estimates. Take estimates for northern 
elephant seal and northern fur seal were increased from 1 to 3 
individuals to account for the large Level B harassment zones for 
certain activities (Table 9).
    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 patterns for individual marine mammals 
resulting from exposure to acoustic sources. Based on the nature of the 
activity and the anticipated effectiveness of the mitigation measures 
(i.e., use of a bubble curtain, wood cushion, and shutdown--discussed 
in detail below in the Mitigation Measures section), Level A harassment 
is neither anticipated nor authorized.
    As described previously, no mortality is anticipated or 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 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 these 
components in more detail and present the take estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 micro pascal ([mu]Pa) root mean square 
(rms) for continuous (e.g., vibratory pile-driving, drilling) and above 
160 dB re 1 [mu]Pa (rms) for non-explosive impulsive (e.g., impact pile 
driving) sources.
    The Port of San Francisco's activity includes the use of continuous 
(vibratory pile driving, down the hole drilling) and impulsive (impact 
pile driving) sources, and therefore the 120 and 160 dB re 1 [mu]Pa 
(rms) thresholds 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). 
The Port of San Francisco's activity includes the use of impulsive 
(impact pile driving) and non-impulsive (vibratory pile driving) 
sources.
    These thresholds are provided in Table 3 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS's 2018 Technical Guidance, which may be accessed at: 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

[[Page 53222]]



                     Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                     PTS onset acoustic thresholds * (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1 [mu]Pa2s. 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 
coefficients.
    Reference sound source levels used by the Port of San Francisco for 
all vibratory and impact piling/removal and drilling activities were 
derived from source level data from construction projects within 
Caltrans (2015) except for two cases noted below where Navy and Alaska 
Department of Transportation sources were used. To determine the 
ensonified areas for both the Level A and Level B harassment zones for 
vibratory piling of the 36-inch, 30-inch, and 16-inch steel piles and 
14-inch steel H piles, the Port of San Francisco used sound pressure 
levels (SPL) of 170 dB re 1 [mu]Pa rms, 170 dB re 1 [mu]Pa rms, 158 dB 
re 1 [mu]Pa rms, and 158 dB re 1 [mu]Pa rms, respectively. These were 
derived from vibratory pile driving data of 36-inch (for 36-inch and 
30-inch steel piles), 18-inch (for 16-inch steel piles) and 14-inch 
(for 14-inch steel H-pile) steel piles reported in the values listed in 
Table 1.2-2 and Table 1.2.3 of Caltrans (2015), and Table 6-1 of Navy 
(2017). For vibratory pile removal, the Port of San Francisco used an 
SPL of 155 dB re 1 [mu]Pa rms. This proxy source level was derived from 
vibratory pile driving data of 12-inch steel pipe piles in Caltrans 
(2015; Table 1.2-2). In addition, for down the hole drilling activities 
used to place 24-inch octagonal concrete piles, an SPL of 168 dB was 
used, corresponding to the mean SPL reported in Table 72 of the Alaska 
Department of Transportation (2016) hydroacoustic report.
    For impact pile driving, the Port of San Francisco used both SPLs 
and sound exposure levels (SEL) derived from summary source level 
values reported in Caltrans (2015). These source levels were then 
reduced by 7 dB due to the Port of San Francisco's use of a bubble 
curtain. NMFS used a reduction value of 7 dB as it was roughly the 
average sound reduction value derived from sound measurements of piles 
that used bubble curtains within Caltrans (2015). For piling of 36-inch 
steel piles, a source level of 183 dB SEL was chosen as a proxy value 
for modeling Level A harassment zones (Caltrans 2015, Table 1.2-1). 
This source level was reduced to 176 dB SEL with the 7 dB reduction. 
For piling of 20-inch concrete piles, a source level of 167 dB SEL was 
chosen as a proxy value for modeling Level A harassment zones (Caltrans 
2015, Table 1.5-4, reported from 24-inch concrete pile measurements at 
a project in the Port of Oakland). This source level was selected as a 
proxy because of the proximity of the Port of Oakland project to the 
proposed work and it is more conservative than Caltrans (2015) summary 
value reported in Table 1.2-1. This source level was reduced to 160 dB 
SEL with the 7 dB reduction. In addition, for impact piling of 16-inch 
steel piles, a source level of 158 dB SEL was chosen as a proxy value 
for modeling Level A harassment zones (Caltrans 2015, Table I.2-1). 
This source level was reduced to 151 dB SEL with the 7 dB reduction. 
The stated source levels and their corresponding activity are presented 
in Table 4 below.

                     Table 4--Project Source Levels
------------------------------------------------------------------------
                                              Source level at 10 meters
                 Activity                               (dB)
------------------------------------------------------------------------
Vibratory Pile Driving/Removal:
    36-inch steel pile installation.......  170 SPL
    30-inch steel pile installation         170 SPL
     (Caisson).
    14-inch steel H pile installation.....  158 SPL
    Removal of pre-existing piles.........  155 SPL
    16-inch steel pile installation.......  158 SPL
Impact Pile Driving: *
    36-inch steel pile installation.......  176 SEL/186 SPL
    20-inch concrete pile installation....  160 SEL/172 SPL
    16-inch steel pile installation.......  151 SEL/177 SPL
Down the Hole Drilling:

[[Page 53223]]

 
    24-inch Octagonal Concrete (drilling    168 SPL
     of 30-inch hole).
------------------------------------------------------------------------
* The values in the cells reflect a 7dB reduction due to the Port of San
  Francisco's use of a bubble curtain.

Level B Harassment Zones

    The practical spreading model was used by the Port of San Francisco 
to generate the Level B harassment zones for all piling/removal 
activities. Practical spreading is described in full detail below.
    Pile driving and drilling generates underwater noise that can 
potentially result in disturbance to marine mammals in the project 
area. 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.

This formula neglects 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]). 
A practical spreading value of 15 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.
    Utilizing the practical spreading loss model, the Port of San 
Francisco determined underwater noise will fall below the behavioral 
effects threshold of 120 dB rms for marine mammals at a maximum radial 
distance of 21,544 m for vibratory piling (36 and 30-inch steel piles) 
and 15,849 m for drilling ((24-inch octagonal concrete pile). The 
maximum Level B harassment zone for this activity will therefore be set 
at 21,544 m. However, previous sound monitoring for other projects in 
San Francisco Bay (i.e. Caltrans 2015; 2016) have shown background 
sound levels in the active portions of the Bay, near the project area, 
to range from 110 to 140 dB rms, with typical background levels in the 
range of 110 to 120 dB rms. This ambient noise may affect the ability 
to distinguish sound from vibratory pile driving in the region (Rodkin, 
2009), but direct applicability of that finding to the Port's work is 
unknown, and therefore no reduction in Level B harassment zone is 
applied. The maximum radial distance of the Level B harassment zone for 
impact pile driving equaled 541.2 m (impact driving 36-inch steel 
piles). At this radial distance, the entire Level B harassment zone for 
impact piling equaled 0.3699 square kilometers (km\2\). This ensonified 
area is based on a GIS map of the area accounting for structures and 
landmasses which would block sound spreading (Please see Figure 9 of 
the Application). Table 5 below provides all Level B radial distances 
and their corresponding areas for each activity during the Port of San 
Francisco's project. Level B harassment zone areas are calculated using 
a GIS map (See Figure 9 of the Application).

    Table 5--Level B Harassment Zones Calculated Using the Practical
                             Spreading Model
------------------------------------------------------------------------
                                        Calculated          Level B
                                    distance to Level   harassment zone
              Source                   B threshold          (square
                                         (meters)      kilometers km\2\)
------------------------------------------------------------------------
                         Vibratory Pile Driving
------------------------------------------------------------------------
36-inch steel pile installation...             21,544            47.1608
30-inch steel pile installation...             21,544            47.1608
16-inch steel pile installation...              3,415             7.6431
14-inch steel H pile installation.              3,415             7.6431
Removal of pre-existing concrete                2,154             3.1511
 and wood piles...................
------------------------------------------------------------------------
                           Impact Pile Driving
------------------------------------------------------------------------
36-inch steel pile installation...              541.2            0.36993
20-inch concrete pile installation               63.1           0.006650
16-inch steel pile installation...                136             0.0291
------------------------------------------------------------------------
                         Down the Hole Drilling
------------------------------------------------------------------------
                                               15,849            47.1608
------------------------------------------------------------------------


[[Page 53224]]

Level A Harassment Zones

    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that the ensonified area 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 will result in some 
overestimate of Level A harassment. 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 (i.e. pile 
driving), NMFS's 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. Daily 
ensonified areas for Level A harassment are approximated as a semi-
circle because the pile driving and drilling are occurring close to 
shore and the coastline is approximately linear.

                                                                    Table 6--Parameters of Pile Driving and Drilling Activity
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Vibratory pile    Vibratory pile    Vibratory pile    Vibratory pile
                                 Vibratory pile        driver            driver            driver            driver          Impact pile       Impact pile       Impact pile     Drilling  (24-
        Equipment type          driver  (removal  (installation of  (installation of  (installation of  (installation of  driver  (36-inch  driver  (20-inch  driver  (16-inch   inch  octagonal
                                of  concrete and    36-inch steel     30-inch steel     16-inch steel    14-inch steel H    steel piles)     concrete piles)    steel piles)     concrete pile)
                                   wood piles)         piles)            piles)            piles)            piles)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used..........  Non-impulsive,    Non-impulsive,    Non-impulsive,    Non-impulsive,    Non-impulsive,    Impulsive, Non-   Impulsive, Non-   Impulsive, Non-   Non-impulsive,
                                 continuous.       continuous.       continuous.       continuous.       continuous.       continuous.       continuous.       continuous.       continuous.
Source Level..................  155 SPL.........  170 SPL.........  170 SPL.........  158 SPL.........  158 SPL.........  176 SEL *.......  160 SEL *.......  151 SEL *.......  168 SPL.
Weighting Factor Adjustment     2.5.............  2.5.............  2.5.............  2.5.............  2.5.............  2...............  2...............  2...............  2.
 (kHz).
(a) Activity duration (hours)   (a) 0.66........  (a) 1.33........  (a) 0.25........  (a) 0.33........  (a) 0.66........  (b) 150, (c) 4..  (b) 500, (c) 4..  (b) 500, (c) 2..  (a) 5.5.
 within 24 hours, (b) Number
 of strikes per pile, (c)
 Number of piles per day.
Propagation (xLogR)...........  15..............  15..............  15..............  15..............  15..............  15..............  15..............  15..............  15.
Distance of source level        10..............  10..............  10..............  10..............  10..............  10..............  10..............  10..............  10.
 measurement (meters) +.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Displayed source values include the 7 dB reduction for use of a bubble curtain.


           Table 7--Level A Harassment Zone Isopleth and Ensonified Area for Pile Driving and Drilling
----------------------------------------------------------------------------------------------------------------
                                                                         PTS isopleth (meters)
                                                     -----------------------------------------------------------
                     Source type                         Low-        Mid-        High-
                                                       frequency   frequency   frequency    Phocid      Otariid
                                                       cetaceans   cetaceans   cetaceans   pinnipeds   pinnipeds
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driver (Removal of concrete and wood          1.5         0.1         2.2         0.9         0.1
 piles).............................................
Vibratory Pile Driver (Installation of 36-inch steel        32.9         2.9        48.7        20.0         1.4
 piles).............................................
Vibratory Pile Driver (Installation of 30-inch steel        10.8         1.0        16.0         6.6         0.5
 piles).............................................
Vibratory Pile Driver (Installation of 14-inch steel         3.3         0.3         4.9         2.0         0.1
 H piles)...........................................
Vibratory Pile Driver (Installation of 16-inch steel         2.1         0.2         3.0         1.3         0.1
 H piles)...........................................
Impact Pile Driver (36-inch steel piles)............       242.6         8.6       288.9       129.8         9.5
Impact Pile Driver (20-inch concrete piles).........        46.4         1.7        55.3        24.8         1.8
Impact Pile Driver (16-inch steel piles)............         7.3         0.3         8.8         3.9         0.3
Drilling(24-inch octagonal concrete pile)...........        62.7         3.5        54.9        33.5         2.4
----------------------------------------------------------------------------------------------------------------
                                          Daily ensonified area (m\2\)
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driver (Removal of concrete and wood          3.5        0.02         7.6         1.3        0.02
 piles).............................................
Vibratory Pile Driver (Installation of 36-inch steel       1,700          13       3,730         628         3.1
 piles).............................................
Vibratory Pile Driver (Installation of 30-inch steel         183         1.6         402          68         0.4
 piles).............................................
Vibratory Pile Driver (Installation of 14-inch steel          17        0.14          37         6.3        0.02
 H piles)...........................................
Vibratory Pile Driver (Installation of 16-inch steel         6.9        0.06          14         2.7        0.02
 H piles)...........................................
Impact Pile Driver (36-inch steel piles)............      92,450         120     131,100      26,460         140
Impact Pile Driver (20-inch concrete piles).........       3,380         4.5       4,800         966         5.1
Impact Pile Driver (16-inch steel piles)............          84         0.1         120          24         0.1
Drilling(24-inch octagonal concrete pile)...........       6,180          19       4,730       1,760         9.0
----------------------------------------------------------------------------------------------------------------

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.
    No systematic line transect surveys of marine mammals have been 
performed in San Francisco Bay. Therefore, the in-water densities of 
harbor seals, California sea lions, and harbor porpoises were 
calculated based on 17 years of observations during monitoring for the 
San Francisco Bay-Oakland Bay Bridge (SFOBB) construction and 
demolition project (Caltrans 2018). Care was taken to eliminate 
multiple observations of the same animal, although this can be 
difficult and is likely that the same individual may have been counted 
multiple times on the same day. The amount of monitoring

[[Page 53225]]

performed per year varied, depending on the frequency and duration of 
construction activities with the potential to affect marine mammals. 
During the 257 days of monitoring from 2000 through 2017 (including 15 
days of baseline monitoring in 2003), 1,029 harbor seals, 83 California 
sea lions, and 24 harbor porpoises were observed in waters in the 
project vicinity in total. In 2015, 2016, and 2017, the number of 
harbor seals in the project area increased significantly. In 2017, the 
number of harbor porpoise in the project area also increased 
significantly. Therefore, a harbor seal density estimate was calculated 
using the 2015-2017 data, and a harbor porpoise density estimate was 
calculated using the 2017 data, which may better reflect the current 
use of the project area by these animals. These observations included 
data from baseline, pre-, during, and post-pile driving, mechanical 
dismantling, on-shore blasting, and off-shore implosion activities.
    Insufficient sighting data exist to estimate the density of 
bottlenose dolphins. However, a single bottlenose dolphin has been 
observed regularly near the project site. One individual was documented 
regularly, through photo ID, over several months off the coast of the 
former Alameda Air Station (Perlman 2017).
    Insufficient sighting data exist to estimate elephant seal 
densities in the Bay. Generally, only juvenile elephant seals enter the 
Bay and do not remain long. The most recent sighting near the project 
area was in 2012, on the beach at Clipper Cove on Treasure Island, when 
a healthy yearling elephant seal hauled out for approximately 1 day. 
Approximately 100 juvenile northern elephant seals strand in or near 
the Bay each year, including individual strandings at Yerba Buena 
Island and Treasure Island (less than 10 strandings per year).
    In addition, insufficient sighting data exist to estimate northern 
fur seal and gray whale densities in the Bay. Only two to four northern 
fur seals strand in the Bay each year, and they are unlikely to occur 
in the project area. Also, during the Caltrans Richmond-San Rafael 
Bridge project, monitors recorded 12 living and two dead gray whales in 
the surveys performed in 2012. All sightings were in either the Central 
or North Bay, and all but two sightings occurred during the months of 
April and May. One gray whale was sighted in June and one in October. 
The Oceanic Society has tracked gray whale sightings since they began 
returning to San Francisco Bay regularly in the late 1990s. Most 
sightings occurred just a mile or two inside of the Golden Gate, with 
some traveling into San Pablo Bay in the northern part of the San 
Francisco Bay (Self 2012). The Oceanic Society data show that all age 
classes of gray whales enter San Francisco Bay and they enter as 
singles or in groups of up to five individuals (Winning 2008). It is 
estimated that two to six gray whales enter San Francisco Bay in any 
given year.
    Numbers used for density calculations are shown in Table 8. These 
numbers were calculated from observations in nearby waters of the San 
Francisco Bay during San Francisco-Oakland Bay Bridge construction 
conducted by Caltrans (Caltrans 2018). These observations occurred from 
2000 to 2017 in a 2 km\2\ monitoring zone for California sea lions, 
from 2015-2017 in a 2 km\2\ monitoring zone for harbor seals, and in 
2017 in a 15 km\2\ zone for harbor porpoise. In the cases where 
densities were refined to capture a narrower range of years to be 
conservative, bold densities were used for take calculations.

             Table 8--Estimated In-Water Density of Marine Mammal Species in San Francisco Bay Area
                                                 [Caltrans 2017]
----------------------------------------------------------------------------------------------------------------
                                            Area of                        Number of
           Species observed               monitoring        Days of         animals       Density animals/km\2\
                                         zone (km\2\)     monitoring       observed
----------------------------------------------------------------------------------------------------------------
Harbor seals 2000-2017................               2             257           1,029  2.002.
Harbor Seals 2015-2017................               2              47             372  3.957.
California Sea Lions 2000-2017........               2             257              83  0.161.
Bottlenose Dolphins 2017..............               2               6               2  Insufficient sighting
                                                                                         data exists to estimate
                                                                                         density.
Harbor Porpoise 2000-2017.............               3             257              24  0.031.
Harbor Porpoise 2017..................              15               6              15  0.167.
Elephant Seal 2000-2017...............               2             257               0  Insufficient sighting
                                                                                         data exists to estimate
                                                                                         density.
Northern Fur Seal 2000-2017...........               2             257               0  Insufficient sighting
                                                                                         data exists to estimate
                                                                                         density.
Gray Whale 2000-2017..................               2             257               0  Insufficient sighting
                                                                                         data exists to estimate
                                                                                         density.
----------------------------------------------------------------------------------------------------------------
Notes:
Densities for Pacific harbor seals, California sea lions, and harbor porpoises are based on monitoring for the
  east span of the SFOBB from 2000 to 2017.
A second set of Pacific harbor seal densities were calculated from the increase in sightings recorded from 2015
  to 2017.
A second set of harbor porpoise densities were calculated for the increase in sightings that were recorded in
  2017.
Bold densities were used for take calculations.
Sources: CalTrans 2001, 2004b, 2013b, 2013c, 2014, 2015b, 2016, 2017; Perlman 2017.

    For species without enough sightings to construct a density 
estimate, we used information based on group size and frequency of 
sightings from previous years of work to inform the number of animals 
estimated to be taken, which is detailed in the Take Estimation section 
below.

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, Level B take for the project was 
calculated by multiplying the density times the largest Level B 
harassment zone (km\2\) times the number of construction days. Since 
density data was only available for harbor seals,

[[Page 53226]]

harbor porpoises, and California sea lions, these were the only species 
whose take was calculated used this methodology. Table 9 shows the 
number of take calculated for species with density and without density 
estimates. For species without density information, information on 
average group size of the species was used. This is discussed below 
Table 9.

                           Table 9--Take Estimates as a Percentage of Stock Abundance
----------------------------------------------------------------------------------------------------------------
                                                      Level B
                                Density animals/    harassment     Construction   Proposed Level   Percentage of
            Species                   km\2\        zone (km\2\)      days \2\         B take           stock
                                                        \1\
----------------------------------------------------------------------------------------------------------------
Harbor Seal...................  3.957...........         47.1608              15           2,799             9.0
California Sea Lions..........  0.161...........         47.1608              15             114           0.038
Harbor Porpoise...............  0.167...........         47.1608              15             118             1.2
Northern Elephant Seal........  Insufficient             47.1608              15               3          0.0034
                                 sighting data
                                 exists to
                                 estimate
                                 density.
Northern Fur Seal.............  Insufficient             47.1608              15               3          0.0005
                                 sighting data
                                 exists to
                                 estimate
                                 density.
Gray Whale....................  Insufficient             47.1608              15               3           0.014
                                 sighting data
                                 exists to
                                 estimate
                                 density.
Bottlenose Dolphin............  Insufficient             47.1608              15              15             3.3
                                 sighting data
                                 exists to
                                 estimate
                                 density.
----------------------------------------------------------------------------------------------------------------
\1\ Represents area of largest Level B harassment zone during pile driving/removal and drilling activities.
\2\ Total construction days for pile driving/removal and drilling.

Gray Whale
    Gray whales occasionally enter San Francisco Bay during their 
northward migration period of February and March. Pile driving and 
drilling are not proposed to occur during this time and gray whales are 
not likely to be present at other times of the year. It is estimated 
that two to six gray whales enter the Bay in any given year, but they 
are unlikely to be present during the work period (June 1 through 
November 30). However, individual gray whales have occasionally been 
observed in San Francisco Bay during the work period, and therefore it 
is conservatively estimated that, at most, 3 gray whales, or one 
average sized group, may be exposed to Level B harassment during the 15 
days of pile driving/drilling.
Bottlenose Dolphin
    When bottlenose dolphins are present in San Francisco Bay, they are 
more typically found close to the Golden Gate. Recently, beginning in 
2015, two individuals have been observed frequently in the vicinity of 
Oyster Point (GGCR 2016, 2017; Perlman 2017) and one individual has 
been observed near Alameda (GGCR 2016). Observations of bottlenose 
dolphins are primarily west of Treasure Island and concentrated along 
the nearshore areas of San Francisco south to Redwood City (Caltrans 
2018). Bottlenose dolphins rarely occur in San Francisco Bay, but given 
the size of the Level B harassment zone NMFS authorizes take of 15 
bottlenose dolphins by level B harassment.
Northern Fur Seal
    Observations of northern fur seals are too few to establish a 
density for this species in San Francisco Bay. The Marine Mammal Center 
(TMMC) reported only two to four northern fur seal strandings in the 
Bay in 2015 and 2016 (in Marin, San Francisco, and Santa Clara 
counties) (TMMC 2017). To account for the possible rare presence of the 
species in the action area, NMFS authorizes three takes by Level B 
harassment of northern fur seal.
Northern Elephant Seal
    Elephant seals breed between December and March and have been 
rarely cited in San Francisco Bay. It is anticipated that if an 
elephant seal is encountered at all during pile driving or drilling it 
would be a juvenile. To account for the possible rare presence of the 
species in the action area, NMFS authorizes three takes by Level B 
harassment of elephant seal.
Level A Harassment
    High frequency cetaceans (including harbor porpoise) have the 
largest Level A harassment zone resulting from this project as shown in 
Table 7. Estimated take by Level A harassment for harbor porpoise, 
based on density reported in Table 8 and the Level A harassment zone, 
is less than one individual (Density * Days * Ensonified Area). Given 
the required mitigation measures, including shutdown zones which exceed 
the Level A harassment zone, NMFS authorizes no Level A harassment for 
harbor porpoise or any marine mammal.

Mitigation Measures

    The only change to mitigation measures were updates to the minimum 
shutdown zones to reflect the changes in Level A harassment zones 
discussed in the previous section.
    In order to issue an IHA under Section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting such 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse

[[Page 53227]]

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.
    In addition to the specific measures described later in this 
section, the Port must conduct briefings for construction supervisors 
and crews, the monitoring team, and Port staff prior to the start of 
all pile driving activity, and when new personnel join the work, in 
order to explain responsibilities, communication procedures, the marine 
mammal monitoring protocol, and operational procedures.

Timing Restrictions

    All work will be conducted during daylight hours. If poor 
environmental conditions restrict full visibility of the shutdown zone, 
pile installation would be delayed.

Sound Attenuation

    Sound attenuation methods, including a bubble curtain, will be 
implemented for the duration of impact pile driving to install 36-inch 
and 16-inch steel and 20-inch concrete piles. Additionally, a caisson 
sleeve will be used during down the whole drilling. The Port shall 
implement the following bubble curtain performance standards:
     The bubble curtain must distribute air bubbles around 100 
percent of the piling perimeter for the full depth of the water column;
     The lowest bubble ring shall be in contact with the 
mudline for the full circumference of the ring, and the weights 
attached to the bottom ring shall ensure 100 percent mudline contact. 
No parts of the ring or other objects shall prevent full mudline 
contact;
     The selected contractor will ensure that personnel are 
trained in the proper balancing of air flow to the bubblers and shall 
require that construction contractors submit an inspection/performance 
report for approval by the Port of San Francisco within 72 hours 
following the performance test. Corrections to the attenuation device 
to meet the performance standards shall occur prior to impact driving.

Shutdown Zone For In-Water Heavy Machinery Work

    For in-water heavy machinery work (using, e.g., standard barges, 
tug boats, barge-mounted excavators, or clamshell equipment used to 
place or remove material), a minimum 10 meter shutdown zone shall be 
implemented. If a marine mammal comes within 10 m of such operations, 
operations shall cease and vessels shall reduce speed to the minimum 
level required to maintain steerage and safe working conditions. This 
type of work could include (but is not limited to) the following 
activities: (1) Vibratory pile driving; (2) movement of the barge to 
the pile location; (3) positioning of the pile on the substrate via a 
crane (i.e., stabbing the pile); or (4) removal of the pile from the 
water column/substrate via a crane (i.e., deadpull).

Additional Shutdown Zones

    For all pile driving/removal and drilling activities, The Port of 
San Francisco will establish a shutdown zone for a marine mammal 
species that is greater than its corresponding Level A harassment zone. 
The purpose of a shutdown zone is generally to define an area within 
which shutdown of the activity would occur upon sighting of a marine 
mammal (or in anticipation of an animal entering the defined area). The 
shutdown zones for each of the pile driving and drilling activities are 
listed below in Table 10.

                                            Table 10--Shutdown Zones
----------------------------------------------------------------------------------------------------------------
                                                               Shutdown zones (meters)
                                    ----------------------------------------------------------------------------
                                      Low-frequency                  High-  frequency
               Source                   cetaceans     Mid-frequency      cetaceans                      Otariid
                                        (humpback       cetaceans         (Dall's      Phocid (harbor     (sea
                                      whale, minke   (Pacific-white  porpoise, harbor       seal)        lion)
                                         whale)      sided dolphin)      porpoise)
----------------------------------------------------------------------------------------------------------------
                                       In-Water Construction Activities *
----------------------------------------------------------------------------------------------------------------
In Water Heavy Construction (i.e.,               10              10                10              10         10
 Barge movements, pile positioning,
 deadpulling, and sound
 attenuation)......................
----------------------------------------------------------------------------------------------------------------
                                             Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driver (Removal of                10              10                10              10         10
 concrete and wood piles)..........
Vibratory Pile Driver (Installation              10              10                10              10         10
 of 14-inch steel H piles).........
Vibratory Pile Driver (Installation              10              10                10              10         10
 of 16-inch steel H piles).........
Vibratory Pile Driver (Installation              25              10                25              10         10
 of 30-inch steel piles)...........
Vibratory Pile Driver (Installation              50              10                75              25         10
 of 36-inch steel piles)...........
----------------------------------------------------------------------------------------------------------------
                                               Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
Impact Pile Driver (16-inch steel                10              10                10              10         10
 piles)............................
Impact Pile Driver (20-inch                      75              10                75              30         10
 concrete piles)...................
Impact Pile Driver (36-inch steel               300              25               300             150         25
 piles)............................
----------------------------------------------------------------------------------------------------------------
                                                    Drilling
----------------------------------------------------------------------------------------------------------------
24-inch concrete pile (1 pile) (5.5              75              10                50              20         10
 hours per day)....................
----------------------------------------------------------------------------------------------------------------


[[Page 53228]]

Monitoring Zones

    The Port of San Francisco will establish and observe a monitoring 
zone. The monitoring zones for this project will differ based on 
activity. For vibratory pile driving and down the hole drilling, it may 
not be possible to observe the entire Level B harassment zones (areas 
where SPLs are equal to or exceed 120 dB rms) due to their size. The 
Port is expected to monitor and record observations in the largest 
reasonable portion of this Level B harassment zone based on the number 
of observers and visibility, but conditions may require efforts to be 
focused in a smaller monitoring zone. For impact pile driving, the 
monitoring zones are areas where SPLs are equal to or exceed 160 dB 
rms. For vibratory pile driving/drilling and impact pile driving the 
Level B Harassment zones are presented in Table 11 below. For the 
vibratory pile driving and drilling activities, it is noted that Level 
B harassment zone radius and area will not necessarily equal the 
monitoring zone. These zones provide utility for monitoring conducted 
for mitigation purposes (i.e., shutdown zone monitoring) by 
establishing monitoring protocols for areas adjacent to the shutdown 
zones. Monitoring of disturbance zones enables observers to be aware of 
and communicate the presence of marine mammals in the project area, but 
outside the shutdown zone, and thus prepare for potential shutdowns of 
activity. However, the primary purpose of disturbance zone monitoring 
is for documenting instances of Level B harassment; disturbance zone 
monitoring is discussed in detail later (see Monitoring and Reporting).

                       Table 11--Monitoring Zones
------------------------------------------------------------------------
                                              Radial
                                            Distance to       Level B
                 Source                       Level B       Harassment
                                             threshold      Zone  (km2)
                                             (meters)
------------------------------------------------------------------------
                         Vibratory Pile Driving
------------------------------------------------------------------------
36-inch steel pile installation.........        * 21,544       * 47.1608
30-inch steel pile installation.........        * 21,544       * 47.1608
16-inch steel pile installation.........         * 3,415        * 7.6431
14-inch steel H pile installation.......         * 3,415        * 7.6431
Removal of pre-existing concrete and             * 2,154        * 3.1511
 wood piles.............................
------------------------------------------------------------------------
                           Impact Pile Driving
------------------------------------------------------------------------
36-inch steel pile installation.........           541.2          0.3699
20-inch concrete pile installation......            63.1        0.006650
16-inch steel pile installation.........             136          0.0291
------------------------------------------------------------------------
                         Down the Hole Drilling
------------------------------------------------------------------------
                                                * 15,849       * 47.1608
------------------------------------------------------------------------
* The monitored radius and area of the Level B harassment zone may vary
  based on visibility.

Non-Authorized Take Prohibited

    If a species enters or approaches the Level B harassment zone and 
that species is either not authorized for take or its authorized takes 
are met, pile driving, pile removal, and drilling 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.

Soft Start

    The use of a soft-start procedure is 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 impact hammer operating 
at full capacity. For impact pile driving, contractors will be required 
to provide an initial set of strikes from the hammer at 40 percent 
energy, each strike followed by no less than a 30-second waiting 
period. This procedure will be conducted a total of three times before 
impact pile driving begins. This soft start procedure must be 
implemented at the start of a day's impact pile driving and at any time 
following cessation of impact driving of 30 minutes or greater. Soft 
start is not required during vibratory pile driving/removal or drilling 
activities.

Pre-Activity Monitoring

    Prior to the start of daily in-water construction activity, or 
whenever a break in pile driving or drilling of 30 minutes or longer 
occurs, the observer will observe the shutdown and monitoring zones for 
a period of 30 minutes. The shutdown zone will be cleared when a marine 
mammal has not been observed within the zone for that 30-minute period. 
A determination that the shutdown zone is clear must be made during a 
period of good visibility (i.e., the entire shutdown zone and 
surrounding waters must be visible to the naked eye). If a marine 
mammal is observed within the shutdown zone, a soft-start cannot 
proceed until the animal has left the zone or has not been observed for 
15 minutes. If the monitoring zone has been observed for 30 minutes and 
non-permitted species are not present within the zone, soft start 
procedures can commence and work can continue even if visibility 
becomes impaired within the monitoring zone. When a marine mammal 
permitted for take by Level B harassment is present in the monitoring 
zone, pile driving, pile removal, and drilling activities may begin and 
take by Level B harassment will be recorded. As stated above, if the 
entire Level B harassment zone is not visible at the start of 
construction, piling or drilling activities can begin. If work ceases 
for more than 30 minutes, the pre-activity monitoring of both the 
monitoring zone and shutdown zone will commence.
    Based on our evaluation of the applicant's mitigation measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
mitigation measures provide the means effecting the least practicable 
impact on

[[Page 53229]]

the affected species or stocks and their habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance.

Monitoring and Reporting

    Between the proposed IHA and final IHA, the only change to 
monitoring and reporting protocols were a decrease in the required 
minimum number of protected species observers (PSOs) from two to one. 
To minimize the burden of monitoring on the applicant, two PSOs will be 
used for the first week of the project. Later portions of the project 
will utilize one PSO if monitoring results up to that point have not 
shown unexpectedly high numbers of marine mammals. NMFS determined that 
one PSO is sufficient to effectively observe the shutdown zones and a 
portion of the monitoring zone. This level of observation minimized 
burden on the applicant while still ensuring effective monitoring. 
Additionally, the use of two PSOs for a portion of the project will 
increase understanding of the impacts of this and similar projects on 
marine mammals in San Francisco Bay, while not placing an excessive 
burden on the Port of San Francisco.
    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 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;
     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.

Hydroacoustic Monitoring

    The Port recognizes in their application the need to implement a 
sound monitoring plan (SMP) as required by the Regional NMFS and U.S. 
Army Corps of Engineers programmatic review for pile driving activities 
in San Francisco Bay. The Port indicates that this SMP will recommend 
sound monitoring stations at 10 m, 100 m, and 300 m to monitor ambient 
noise conditions in the area. NMFS feels that ambient noise 
measurements are highly specific to the time and place they were taken, 
and therefore might have limited use to future projects. However, there 
are few source level measurements for down the hole drilling 
activities, as shown by the use of Alaska DOT proxy data in this IHA. 
NMFS feels that rigorous hydroacoustic monitoring of source level for 
the down the hole drilling activity will be more beneficial for future 
projects in this region and others. While NMFS is not requiring these 
source level measurements, if the Port were already planning to conduct 
measurements, we recommend focusing on source level verification and 
could offer guidance on its implementation.

Visual Monitoring

    Monitoring would be conducted 30 minutes before, during, and 30 
minutes after all 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, removed, or pile holes being drilled. Pile driving and drilling 
activities include the time to install, remove, or drill a hole for 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.
    Monitoring will be conducted by NMFS approved PSOs. There will be a 
minimum of one PSO during all pile driving/removal and drilling 
activities. Two PSOs will be required to observe the shutdown and 
disturbance zones for the first five (5) days of combined pile driving, 
pile removal, and drilling.
    PSOs shall scan the waters using binoculars, and/or spotting 
scopes, and shall use a handheld GPS or range-finder device to verify 
the distance to each sighting from the project site. All PSOs shall be 
trained in marine mammal identification and behaviors and are required 
to have no other project-related tasks while conducting monitoring. In 
addition, monitoring shall be conducted by qualified observers, who 
shall be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown/delay procedures when applicable 
by calling for the shutdown to the hammer operator. Qualified observers 
are trained and/or experienced professionals, with the following 
minimum qualifications:
    i. At least one PSO must have prior experience working as a marine 
mammal observer during construction activities;
     Independent observers (i.e., not construction personnel);
    ii. Other PSOs may substitute education (degree in biological 
science or related field) or training for experience;
    iii. Where a team of three or more PSOs are required, a lead 
observer or monitoring coordinator shall be designated. The lead 
observer must have prior experience working as a marine mammal observer 
during construction;
    iv. The Port of San Francisco shall submit PSO CVs for approval by 
NMFS;

The Port of San Francisco shall ensure that observers have the 
following additional qualifications:
     Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
     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;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of

[[Page 53230]]

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;
     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
     Sufficient training, orientation, or experience with the 
construction operations to provide for personal safety during 
observations.
    The Port of San Francisco shall submit a draft report to NMFS not 
later than 90 days following the end of construction activities. The 
Port of San Francisco shall provide a final report within 30 days 
following resolution of NMFS' comments on the draft report. Reports 
shall contain, at minimum, the following:
     Date and time that monitored activity begins and ends for 
each day conducted (monitoring period);
     Construction activities occurring during each daily 
observation period, including how many and what type of piles driven;
     Deviation from initial proposal in pile numbers, pile 
types, average driving times, etc.;
     Weather parameters in each monitoring period (e.g., wind 
speed, percent cloud cover, visibility);
     Water conditions in each monitoring period (e.g., sea 
state, tide state);
     Extrapolated estimates of the total observed Level B 
harassment takes based on the percentage of the Level B harassment zone 
that was not visible or was not monitored.
     For each marine mammal sighting:
    [cir] Species, numbers, and, if possible, sex and age class of 
marine mammals;
    [cir] Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
    [cir] Location and distance from pile driving activities to marine 
mammals and distance from the marine mammals to the observation point;
    [cir] Estimated amount of time that the animals remained in the 
Level B harassment zone;
    [cir] Description of implementation of mitigation measures within 
each monitoring period (e.g., shutdown or delay);
    [cir] Other human activity in the area within each monitoring 
period; and
    [cir] A summary of the following:
    [ssquf] Total number of individuals of each species detected within 
the monitoring zone, and estimated as taken if correction factor 
appropriate;
    [ssquf] Total number of individuals of each species detected within 
the Level A harassment zone and the average amount of time that they 
remained in that zone; and
    [ssquf] Daily average number of individuals of each species 
(differentiated by month as appropriate) detected within the monitoring 
zone, and estimated as taken, if appropriate.

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).
    As stated in the mitigation section, bubble curtains will be used 
and shutdown zones that encompass the area in which Level A harassment 
might be expected to occur will be implemented. As a result, no take by 
Level A harassment is expected nor authorized for this activity. 
Exposures to elevated sound levels produced during pile driving 
activities may cause behavioral responses by an animal, but they are 
expected to be mild and temporary. Effects on individuals that are 
taken by Level B harassment, on the basis of reports in the literature 
as well as monitoring from other similar activities, will likely be 
limited to reactions such as increased swimming speeds, increased 
surfacing time, or decreased foraging (if such activity were occurring) 
(e.g., Thorson and Reyff, 2006; Lerma, 2014). Most likely, individuals 
will simply move away from the sound source and be temporarily 
displaced from the areas of pile driving, although even this reaction 
has been observed primarily only in association with impact pile 
driving. These reactions and behavioral changes are expected to subside 
quickly when the exposures cease. Within the project area, there are no 
critical habitats or other biologically important areas (Calambokidis 
et al., 2015). The area is an active commercial port, and while harbor 
seals, California sea lions, and other marine mammals may be present, 
the area is not an established rookery or breeding ground for local 
populations.
    During all impact driving, implementation of soft start procedures, 
the use of a bubble curtain, and monitoring of established shutdown 
zones will be required. Given sufficient notice through use of soft 
start (for impact driving), marine mammals are expected to move away 
from an irritating sound source prior to it becoming potentially 
injurious. In addition, PSOs will be stationed within the action area 
whenever pile driving/removal and drilling operations are underway. 
Depending on the activity, The Port of San Francisco will employ the 
use of at least one PSO to monitor shutdown and monitoring zones.
    Although the MBFL and WTL Project would have some permanent removal 
of habitat available to marine mammals, the area lost would be 
negligible. Construction of the MBFL and WTL structures and dredging 
for the project will result in the disturbance of up to approximately 
8.4 acres of predominantly fine[hyphen]grained sediment and the 
associated benthic infaunal community. Total habitat disturbed from the 
project activities is estimated at 0.000071 percent of the total South 
San Francisco Bay subtidal habitat available (NOAA 2007). This is a 
relatively small fraction of area relative to the total available 
habitat for foraging and transit for marine mammals. In addition, to 
minimize impacts, in[hyphen]water construction will be limited to 
locally established environmental work windows between June and 
November.
    Overall, impacts to marine mammals and prey species due to the 
Mission Bay Ferry and Water Taxi Landing Project are expected to be 
minor and temporary. The area impacted by the project is very

[[Page 53231]]

small compared to the available habitat around San Francisco Bay. The 
most likely impact to prey will be temporary behavioral avoidance of 
the immediate area. During pile driving and drilling, it is expected 
that fish and marine mammals would temporarily move to nearby locations 
and return to the area following cessation of in-water construction 
activities. Therefore, indirect effects on marine mammal prey during 
the construction are not expected to be substantial.
    In summary and as described above, the following factors primarily 
support our determination that the impacts resulting from this activity 
are not expected to adversely affect the species or stock through 
effects on annual rates of recruitment or survival:
     Mortality is not anticipated or authorized;
     Minimal impacts to marine mammal habitat are expected;
     Bubble curtain and other sound attenuating devices are 
used during impact pile driving will lessen the amount of behavioral 
disturbance and contribute to the alleviation of the likelihood of 
injury;
     Impacts are not occurring in rookeries, or known areas or 
features of special significance for foraging or reproduction in the 
project area;
     Anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior; and
     Required mitigation measures (i.e., shutdown zones) are 
expected to be effective in reducing the effects of the specified 
activity.
    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, 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.
    Take for all species authorized except harbor seal is less than 
five percent of their respective stock abundance. For harbor seal, the 
authorized take is less than 10 percent of the stock abundance. Based 
on this and the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS finds that small numbers of 
marine mammals will be taken relative to the population size of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our action (i.e., the issuance of an incidental 
harassment authorization) with respect to potential impacts on the 
human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations with 
no anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
IHA qualifies to be categorically excluded from further NEPA review.

Endangered Species Act (ESA)

    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.

    Dated: October 16, 2018.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2018-22923 Filed 10-19-18; 8:45 am]
BILLING CODE 3510-22-P