[Federal Register Volume 83, Number 16 (Wednesday, January 24, 2018)]
[Notices]
[Pages 3318-3333]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-01306]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF611


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Waterfront Improvement Projects at 
Portsmouth Naval Shipyard

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
U.S. Department of the Navy (Navy) to incidentally harass, by Level A 
and Level B harassment, marine mammals during construction activities 
associated with waterfront improvement projects at the Portsmouth Naval 
Shipyard (the Shipyard) in Kittery, Maine.

DATES: This Authorization is effective from January 8, 2018, through 
January 7, 2019.

FOR FURTHER INFORMATION CONTACT: Rob Pauline, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as a list of the references cited in 
this document, may be obtained online at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing these 
documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION: 

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct

[[Page 3319]]

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

Summary of Request

    On July 14, 2017, NMFS received a request from the Navy for an IHA 
to take marine mammals incidental to impact pile driving, vibratory 
pile driving, vibratory pile extraction, and drilling associated with 
an ongoing waterfront improvement project at the Shipyard. The 
application was considered adequate and complete on August 25, 2017. 
The Navy's request is for take of harbor porpoise (Phocoena phocoena), 
gray seal (Halichoerus grypus), harbor seal (Phoca vitulina), harp seal 
(Pagophilus groenlandicus) and hooded seal (Cystophora cristata), by 
Level A and Level B harassment (authorization of Level A harassment is 
not proposed for the harp seal or hooded seal). Neither the Navy nor 
NMFS expects serious injury or mortality to result from this activity 
and, therefore, an IHA is appropriate.
    This IHA will cover the second year of a five-year project for 
which the Navy had previously obtained an IHA. The Navy intends to 
request take authorization for subsequent years of the project. NMFS 
previously issued the first IHA to the Navy for this project effective 
from January 8, 2018 through January 7, 2019. The larger 5-year project 
involves restoring and modernizing infrastructure at the Shipyard. The 
Navy complied with all the requirements (e.g., mitigation, monitoring, 
and reporting) of the previous IHA and information regarding their 
monitoring results may be found in the Monitoring and Reporting 
section.

Description of Specified Activity

Overview

    The purpose of the proposed action is to modernize and maximize dry 
dock capabilities for performing current and future missions 
efficiently and with maximum flexibility. The need for the proposed 
action is to correct deficiencies associated with the pier structure at 
Berths 11, 12, and 13 and the Dry Dock 3 caisson and concrete seats to 
ensure that the Shipyard can continue to support its primary mission to 
service, maintain, and overhaul submarines. The proposed action covers 
the second year of activities (January 3, 2018 through January 2, 2019) 
associated with the waterfront improvement projects at the Shipyard in 
Kittery, Maine. The project includes impact and vibratory pile driving, 
vibratory pile removal, and drilling. Construction activities may occur 
at any time during the calendar year. A detailed description of the 
planned waterfront improvement project was provided in the Federal 
Register notice for the proposed IHA (82 FR 56791; November 30, 2017). 
Since that time, no changes have been made to the planned waterfront 
improvement activities. Therefore, a detailed description is not 
provided here. Please refer to that Federal Register notice for the 
description of the specific activity.
    Table 1 shows a summary of the anticipated work effort (e.g., days) 
and numbers planned for installation/extraction of each pile type while 
Table 2 shows estimated hours for each type of pile driving and 
drilling activity.

                                                  Table 1--Year 2 (2018) Planned Construction Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         Number of    Number of
        Activity/ method                 Timing         Number of        Pile type         piles        piles        Overlap days         Production
                                                           days                          installed    extracted                            estimates
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extract Timber Piles/Vibratory    January-December               3  15'' Timber Piles.  ...........           18  ..................  Estimated 6 piles
 Hammer.                           2018.                                                                                               per day.
Install Casing & Drill Sockets/   January-December              56  36'' W-Section               35  ...........  ..................  Estimated less
 Auger Drilling.                   2018.                             Steel.                                                            than one pile
                                                                                                                                       completed per
                                                                                                                                       day. This
                                                                                                                                       includes setting
                                                                                                                                       the casing and
                                                                                                                                       rock socket
                                                                                                                                       drilling.
Install Sheet Pile (SKZ-20) SOE   January-December              12  25'' Sheet Piles            144  ...........  9/during rock       Estimated 12
 Piles/Vibro.                      2018.                             Steel.                                        sockets.            sheets per day.
Remove Sheet Pile(SKZ-20) SOE     January-December               6  25'' Sheet Piles    ...........          144  4/during rock       Estimated 24
 Piles/Vibro.                      2018.                             Steel.                                        sockets.            sheets per day.
Install Road Plate/H-Pile         January-December               3  14'' H-Pile Steel.           12  ...........  2/during rock       Estimated 4 ea.
 Support of Excav. Vibro.          2018.                                                                           sockets.            road plates per
                                                                                                                                       day.
Remove Road Plate/H-Pile Support  January-December               2  14'' H-Pile Steel.  ...........           12  1/during rock       Estimated 8 ea.
 of Excav. Vibro.                  2018.                                                                           sockets.            Road plates per
                                                                                                                                       day.
Install Sheet Pile(AZ50) Sheet    January-December               6  25'' Sheet Piles             74  ...........  ..................  Estimated 13
 wall Bulkhead at DD1- Vibro.      2018.                             Steel.                                                            sheets per day.

[[Page 3320]]

 
Install H-Pile (AZ50) Bulkhead    January-December               2  14'' H-Pile Steel.            4  ...........  ..................  Estimated 2 piles
 Return @West End of 11C- Vibro.   2018.                                                                                               per day.
Install Sheet Pile (AZ50)         January-December               9  25'' Sheet Piles              2  ...........  ..................  Estimated 2 piles
 Bulkhead Return @West End of      2018.                             Steel.                                                            per day.
 11C- Vibro.
Install Support/Sister Pile/      January-December     ...........  14'' H-Pile Steel.           22  ...........  ..................  Estimated 2.6
 Vibro & Impact Hammer.            2018.                                                                                               piles per day.
                                                                                                                                       The vibro would
                                                                                                                                       be used to stick
                                                                                                                                       the pile and the
                                                                                                                                       impact would
                                                                                                                                       drive the pile to
                                                                                                                                       refusal.*
                                                      -------------------------------------------------------------------------------
    Totals......................                       Expected total work days                 293          174  16................  ..................
                                                       (including up to16 days of
                                                       concurrent activities) = 84-100
                                                       days
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* Depending on when these piles are driven in the tide cycle there is potential to install all 22 of the support piles in the dry which would further
  reduce the number of vibratory and impact hammer days. This pile quantity includes all the Support Pile in Berth 11C as well as 8 Support Pile
  remaining from Berth 11A.


                      Table 2--Year 2 (2018) Hours Estimated for Each Pile Driving Activity
----------------------------------------------------------------------------------------------------------------
          Driving type                 Pile type        Number of piles          Days                Hours
----------------------------------------------------------------------------------------------------------------
Impact..........................  14'' H-Pile         22 piles..........  9.................  1.5.
                                   (Sister Pile).
Vibratory.......................  25'' sheet pile,    236 piles/sheet...  27 install 8        216 install 64
                                   15'' timber pile,                       remove.             remove.
                                   14'' H-pile.
Drilling........................  36'' Installation/  35 casings........  56................  448.
                                   Rock Sockets.
----------------------------------------------------------------------------------------------------------------

Comment and Responses

    A notice of NMFS's proposal to issue an IHA to the Navy was 
published in the Federal Register on November 30, 2017 (82 FR 56791). 
That notice described, in detail, the Navy'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 
(Commission).
    Comment 1: The Commission listed four issues that need to be 
resolved prior to issuance of the final IHA including:
     Increasing the estimated Level A harassment takes for 
harbor porpoises from one to two to account for group size;
     increasing the estimated Level B harassment takes for harp 
seals from one to five to account for the potential that harp seals 
could be present on multiple days during the five months when they are 
most likely to occur in the project area;
     authorizing Level B harassment takes of five hooded seals 
to account for the potential that hooded seals could be present on 
multiple days during the five months when they are most likely to occur 
in the project area; and
     clarifying or specifying various mitigation and monitoring 
measure requirements.
    Response: NMFS has agreed to make the changes described above. 
These changes are included in the issued IHA.
    Comment 2: The Commission recommended that NMFS share the rounding 
criteria with the Commission such that the matter of when rounding 
should occur in the take calculation can be resolved in the near 
future.
    Response: NMFS will share the rounding criteria with the Commission 
in the near future and looks forward to working with them to resolve 
this issue.
    Comment 3: The Commission stated that monitoring during all pile-
driving and removal activities is necessary for NMFS and the Navy to be 
confident that mitigation measures are implemented as intended, the 
numbers of marine mammals taken are within the limits authorized, and 
the least practicable impact occurs. The Commission recommended that 
NMFS require the Navy to implement full-time monitoring of the full 
extents of various Level A and B harassment zones using two protected 
species observers (PSOs) during all pile-driving (including drilling 
rock sockets) and removal activities.
    Response: NMFS has authorized the employment of a single PSO on 
one-third of driving days to monitor the shutdown and Level A zones Two 
PSOs will be employed on two-thirds of driving days to monitor 
shutdown, Level A and Level B zones. NMFS is confident that a single 
qualified PSO can effectively monitor shutdown and Level A zones during 
all pile driving and removal activities. A single observer will have a 
complete, unobstructed view of the entirety of shutdown and Level A 
zones and will be able to document takes and call for shutdown or delay 
as appropriate. Adding a second PSO on two-thirds of driving days for 
Level B zone monitoring provides the capability to ensure successful 
implementation of mitigation measures and document that authorized take 
limits are not exceeded. Note that under previously issued IHAs, NMFS 
has not required 100 percent monitoring of Level B zones. In these 
instances, NMFS found that mitigation measures were effectively 
employed and marine mammal takes were under authorized limits.
    Comment 4: The Commission reviewed the marine mammal and 
hydroacoustic monitoring plan and provided extensive comments to NMFS 
during the public comment period. The Commission's submitted comment 
letter features an Addendum listing all of the issues that were raised. 
The Commission recommends that NMFS ensure that all issues summarized 
in the Addendum are addressed and incorporated either into the final 
marine

[[Page 3321]]

mammal and hydroacoustic monitoring plan or the incidental harassment 
authorization itself.
    Response: NMFS will address and incorporate resolutions to issues 
identified in the Addendum into the final marine mammal and 
hydroacoustic monitoring plan.
    Comment 5: The Commission expressed concern about the lack of 
adequate time to provide public comments as well as the abbreviated 
timeframes during which NMFS is able to address public comments. The 
Commission recommended that NMFS ensure that it publishes and finalizes 
proposed incidental harassment authorizations sufficiently before the 
planned start date of the proposed activities to ensure full 
consideration is given to all comments received.
    Response: NMFS will work to provide adequate time for public 
comment and response. NMFS will also seek to process IHA applications 
in a more expeditious manner.

Description of Marine Mammals in the Area of Specified Activities

    Five marine mammal species, including one cetacean and four 
pinnipeds, may inhabit or transit the waters near the Shipyard in the 
lower Piscataqua River during the specified activity. These include the 
harbor porpoise, gray seal, harbor seal, hooded seal, and harp seal. 
None of the marine mammals that may be found in the Piscataqua River 
are listed under the Endangered Species Act (ESA). Table 3 lists the 
marine mammal species that could occur near the Shipyard and their 
estimated densities within the project area. As there are no specific 
density data for any of the species in the Piscataqua River, density 
data from the nearshore zone outside the mouth the Piscataqua River in 
the Atlantic Ocean have been used instead. Therefore, it can be assumed 
that the density estimates presented here for each species are 
conservative and higher than densities that would typically be expected 
in an industrialized, estuarine environment such as the lower 
Piscataqua River in the vicinity of the Shipyard.
    Detailed descriptions of the of the species likely to be affected 
by the Navy's 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 (November 
30, 2017;82 FR 56791); 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 (www.nmfs.noaa.gov/pr/species/mammals/) for generalized species 
accounts.

                              Table 3--Marine Mammal Species Potentially Present in the Piscataqua River near the Shipyard
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                   ESA/ MMPA     Stock abundance (CV,
                                                                                    status;        Nmin, most recent                         Annual M/SI
            Common name                Scientific name            Stock         Strategic (Y/N)    abundance survey)            PBR              \3\
                                                                                      \1\                 \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocoenidae (porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Porpoise...................  Phocoena phocoena...  Gulf of Maine/Bay of  -;N              79,883 (0.32;         706.................          437
                                                           Fundy stock.                           61,415; 2011).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
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                                                             Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray Seal.........................  Halichoerus grypus..  Western North         -;N              unknown 505,000       unknown.............        4,959
                                                           Atlantic stock.                        (best estimate 2014
                                                                                                  Canadian population
                                                                                                  DFO 2014).
Harbor Seal.......................  Phoca vitulina......  Western North         -;N              75,834 (0.15;         2,006...............          389
                                                           Atlantic stock.                        66,884; 2012).
Hooded Seal \4\...................  Cystophora cristata.  Western North         -;N              592,100(-;512,000,    unknown.............        5,199
                                                           Atlantic stock.                        2005).
Harp Seal.........................  Pagophilus            Western North         -;N              7,100,000 (2012)....  unknown.............      306,082
                                     groenlandicus.        Atlantic stock.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
  stock abundance. In some cases, CV is not applicable.
\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.
\4\ Abundance estimates for these stocks are greater than eight years old and are, therefore, not considered current. PBR is considered undetermined for
  these stocks, as there is no current minimum abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates
  and PBR values, as these represent the best available information for use in this document.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from the Navy's construction 
activities for the waterfront improvement project have the potential to 
result in Level B harassment (behavioral disturbance) for marine mammal 
species authorized for take. Level A (injury) harassment in the form of 
permanent threshold shift (PTS) may also occur in limited numbers of 
animals. 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 and 
removal of piles. The potential effects to marine mammals and their 
associated habitat are discussed in detail in the Federal Register 
notice for the proposed IHA (November 30, 2017; 82 FR 56791), 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 
that NMFS has authorized through this IHA, which informed NMFS' 
consideration of

[[Page 3322]]

both ``small numbers'' and the negligible impact determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would be by Level A and Level B harassment, as 
impact and vibratory pile driving as well as drilling have the 
potential to result in auditory injury and disruption of behavioral 
patterns for individual marine mammals. The required mitigation and 
monitoring measures are expected to minimize the severity of such 
taking to the extent practicable.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Described in the most basic way, we estimate take by considering: 
(1) Acoustic thresholds above which NMFS believes the best available 
science indicates marine mammals will be behaviorally harassed or incur 
some degree of permanent hearing impairment; (2) the area or volume of 
water that will be ensonified above these levels in a day; (3) the 
density or occurrence of marine mammals within these ensonified areas; 
and, (4) and the number of days of activities. Below, we describe these 
components in more detail and present the authorized take estimate.

Acoustic Thresholds

    NMFS recommends 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., 2011). 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 [mu]Pa (rms) for continuous non-
impulsive (e.g. vibratory pile-driving, drilling) and above 160 dB re 1 
[mu]Pa (rms) for non-explosive impulsive (e.g., impact pile driving, 
seismic airguns) or intermittent (e.g., scientific sonar) sources.
    The Navy's planned activity includes the use of continuous 
(vibratory pile driving, drilling) and impulsive (impact pile driving) 
sources and, therefore, the 120 and 160 dB re 1 [mu]Pa (rms) are 
applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Technical Guidance, 2016) identifies dual criteria to 
assess auditory injury (Level A harassment) to five different marine 
mammal groups (based on hearing sensitivity) as a result of exposure to 
noise from two different types of sources (impulsive or non-impulsive). 
As noted above, the Navy's planned activity includes both impulsive and 
non-impulsive sources.
    These thresholds are provided in Table 4. The references, analysis, 
and methodology used in the development of the thresholds are described 
in NMFS 2016 Technical Guidance, which may be accessed at: http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
BILLING CODE 3510-22-P

[[Page 3323]]

[GRAPHIC] [TIFF OMITTED] TN24JA18.004

BILLING CODE 3510-22-C

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds.
    Pile driving 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]). 
Although cylindrical spreading loss was applied to driving of 14-inch 
H-piles in the previous IHA, in an effort to maintain consistency NMFS 
utilized practical spreading loss (4.5 dB reduction in sound level for 
each doubling of distance) for all driving and drilling activities for 
this IHA. A practical spreading value of 15 is often used

[[Page 3324]]

under conditions, such as at the Shipyard dock, 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.
    Underwater Sound--The intensity of pile driving sounds is greatly 
influenced by factors such as the type of piles, hammers, and the 
physical environment in which the activity takes place. A number of 
studies have measured sound produced during underwater pile driving 
projects. These data are largely for impact driving of steel pipe piles 
and concrete piles as well as vibratory driving of steel pipe piles.

Source Levels

    Source levels were collected for the four types of piles that would 
be installed and two pile-driving methods planned for the project:
    1. 14-inch steel H-type piles--Used as sister piles and for SOE 
system installation; installed/extracted via vibratory hammer and 
seated as needed with impact hammer.
    2. 15-inch timber piles--Used for re-installation of dolphins at 
Berths 11, 12, and 13 and extracted via vibratory hammer.
    3. 25-inch steel sheet piles--Used for the bulkhead at Berth 11 and 
for SOE installed/extracted via vibratory hammer.
    Reference source levels for the project were determined using data 
for piles of similar sizes, the same pile-driving method as that 
planned for the project, and at similar water depths. While the pile 
sizes and water depths chosen as proxies do not exactly match those for 
the project, they are the closest matches available, and it is assumed 
that the source levels shown in Tables 5, 6, and 7 are the most 
representative for each pile type and associated pile-driving method.
    The intensity of pile driving or sounds is greatly influenced by 
factors such as the type of piles, hammers, and the physical 
environment in which the activity takes place. Reference source levels 
for the planned project were determined using data for piles of similar 
sizes, the same pile driving method as that planned for the project, 
and at similar water depths. While the pile sizes and water depths 
chosen as proxies do not exactly match those for the project, they are 
the closest matches available, and it is assumed that the source levels 
shown in Tables 5, 6, and 7 and are the most representative for each 
pile type and associated pile driving method.
    The Navy analyzed source level values associated with a number of 
projects involving impact driving of steel H-piles to approximate 
environmental conditions and driving parameters at the Shipyard 
(Caltrans 2015). Data from pertinent projects were used to obtain 
average SEL and rms values for H pile impact installation. To be sure 
all values were relevant to the site, the Navy eliminated all piles in 
waters greater than 5 m, as well as all readings measured at ranges 
greater than 10 m. The Navy used all H piles for which the diameter was 
not specified as well as the 14 to 15-inch H piles, converted the dB 
measurements to a linear scale before averaging, and re-converted the 
average measurements to the appropriate dB units. Piles driven at this 
project site will be driven in 0-11 feet of water (0-3.4 m). During low 
tide, piles will essentially be driven in the dry. This varies 
drastically from other Navy projects on the east coast, such as at the 
Naval Submarine Base New London, where 14-inch H piles will be driven 
in water depths of 25 feet (7.62 m). Results are shown in Table 5.

              Table 5--Source Levels for In-Water Impact Hammer 14-inch Steel H-Type (Sister) Piles
----------------------------------------------------------------------------------------------------------------
                                    Water depth      Distance
       Pile size and type               (m)        measured (m)        Peak          RMS (dB)        SEL (dB)
----------------------------------------------------------------------------------------------------------------
15-inch steel H pile............             2-3              10             187             164             154
15-inch steel H pile............             2-3              10             180             165             155
15-inch steel H pile............             2-3              10             194             177             170
Unspecified steel H pile........           0.5-2              10             172             160             147
14-inch steel H pile............             1-5              10             205             184             174
14-inch steel H pile............             1-5              10             206             182             172
14-inch steel H pile............             1-5              10             206             184             174
14-inch steel H pile............             1-5              10             210             190             180
14-inch steel H pile............             1-5              10             212             192             182
14-inch steel H pile............             1-5              10             210             189             179
14-inch steel H pile............             1-5              10             212             190             180
14-inch steel H pile............             1-5              10             205             190             180
14-inch steel H pile............             1-5              10             207             187             177
Unspecified steel H pile........           0-0.9              10  ..............             151             142
Unspecified steel H pile........           0-0.9              10  ..............             154             144
Unspecified steel H pile........           0-0.9              10  ..............             170             159
Unspecified steel H pile........           0-0.9              10  ..............             147             136
Unspecified steel H pile........           0-0.9              10  ..............             147             136
Unspecified steel H pile........           0-0.9              10  ..............             150             143
Unspecified steel H pile........           0-0.9              10  ..............             153             142
Unspecified steel H pile........           0-0.9              10  ..............             151             142
Unspecified steel H pile........           0-0.9              10  ..............             156             146
Unspecified steel H pile........           0-0.9              10  ..............             172             162
Unspecified steel H pile........           0-0.9              10  ..............             161             150
Unspecified steel H pile........           0-0.9              10  ..............             155             145
Unspecified steel H pile........           0-0.9              10  ..............             163             152
Unspecified steel H pile........           0-0.9              10  ..............             178             145
Unspecified steel H pile........           0-0.9              10  ..............             165             154
                                 -------------------------------------------------------------------------------
            Averages              ..............           200.4           181.4           171.3  ..............
----------------------------------------------------------------------------------------------------------------
Source: Caltrans 2015


[[Page 3325]]

    While the average rms value is 181.4, the Navy rounded up to 182 dB 
rms to be conservative. Navy rounded up to 182 from 181.4 to be 
conservative since not all proxy projects listed had RMS values in the 
source documents. However, SEL values were available for each proxy 
project so these calculations are expected to be more accurate, 
eliminating the need to conservatively round up the 171.3 dB SEL 
resulting in a value of 171 dB SEL using standard rounding.
    Table 6 shows the source levels that were utilized to calculate 
isopleths for vibratory driving of 25-inch steel sheet piles, and 15-
inch timber piles. An average value of 163 dB rms at 10 m was used for 
24-inch AZ steel sheet and 150 dB rms at 16 m for 15-inch timber pile. 
For Year 1 work at the Shipyard Berth 11 the contractor has obtained 
initial acoustic readings associated with vibratory driving of 14'' H-
Pile of 148 dB rms at 10 m. Additional details are found in Appendix A 
in the application. NMFS will use 148 dB at 10 m as the source level 
since it is site-specific and more conservative than the 145 dB value 
depicted in Caltrans 2015.

    Table 6--Source Levels for In-Water Vibratory Hammer 24-Inch Steel Sheet Piles, and 15-Inch Timber Piles
----------------------------------------------------------------------------------------------------------------
                                              Distance
   Pile size and pile type     Water depth    measured    Peak (dB)     RMS (dB)     SEL (dB)       Location
                                   (m)          (m)
----------------------------------------------------------------------------------------------------------------
24-inch AZ Steel Sheet \1\...           15           10          177          163          162  Berth 23, Port
                                                                                                 of Oakland, CA.
24-inch AZ Steel Sheet \1\...           15           10          175          162          162  Berth 30, Port
                                                                                                 of Oakland, CA.
24-inch AZ Steel Sheet \1\...           15           10          177          163          163  Berth 35/37 Port
                                                                                                 of Oakland, CA.
24-inch AZ Steel Sheet--                15           10          175          160          160  CA (Specific
 Typical \1\.                                                                                    location
                                                                                                 unknown).
24-inch AZ Steel Sheet--                15           10          182          165          165  CA (Specific
 Loudest \1\.                                                                                    location
                                                                                                 unknown).
24-inch AZ Steel Sheet                  15           10          178          163          163  CA (Specific
 (Average) \1\.                                                                                  location
                                                                                                 unknown).
15-inch Timber Pile \2\......           10           16          164          150  ...........  WSF Port
                                                                                                 Townsend Ferry
                                                                                                 Terminal, WA.
14-inch H-type Pile \3\......            6           10          155          148          145  CA (Specific
                                                                                                 location
                                                                                                 unknown).
----------------------------------------------------------------------------------------------------------------
Source:
\1\ ICF Jones & Stokes and Illingsworth & Rodkin 2012.
\2\ WSDOT 2010.
\3\ CALTRANS 2015.

    Using the data presented in Table 6 and Table 7, underwater sound 
levels were estimated using the practical spreading model to determine 
over what distance the thresholds would be exceeded.
    Drilling is considered a continuous, non-impulsive noise source, 
similar to vibratory pile driving. Very little information is available 
regarding source levels of in-water drilling activities associated with 
nearshore pile installation such as that planned for the Berths 11, 12, 
and 13 structural repairs project. Dazey et al. (2012) attempted to 
characterize the source levels of several marine pile-drilling 
activities. One such activity was auger drilling (including 
installation and removal of the associated steel casing). Auger 
drilling will be employed as part of the Shipyard Project. The average 
sound pressure levels re 1 [mu]Pa rms were displayed for casing 
installation, auger drilling (inside the casing), and casing removal. 
For the purposes of this plan, it is assumed that the casing 
installation and removal activities would be conducted in a manner 
similar to that described in Dazey et al. (2012), primarily via 
oscillation. These average source levels are reported in Table 7.

                                  Table 7--Average Source Levels for Auger Drilling Activities During Pile Installation
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Water depth      Distance
            Drilling activity                    (m)        measured (m)      RMS (dB)                                Location
--------------------------------------------------------------------------------------------------------------------------------------------------------
Casing Installation......................             1-5               1             157  Bechers Bay Santa Rosa Island, CA.
Auger Drilling...........................             1-5               1             151  Bechers Bay Santa Rosa Island, CA.
Casing Removal...........................             1-5               1             152  Bechers Bay Santa Rosa Island, CA.
Average Drilling Activity................             1-5               1             154  .............................................................
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source: Dazey et al., 2012.
Note: All source levels are referenced to 1 microPascal (re 1 [mu]Pa).

    IHA applications for other construction projects have reported 
that, due to a lack of information regarding pile drilling source 
levels, it is generally assumed that pile drilling would produce less 
in-water noise than both impact and vibratory pile driving. Based on 
the general lack of information about these activities and the 
assumption that in-water noise from pile drilling would be less than 
either impact or vibratory pile driving, it is assumed that the source 
levels presented in Table 7 are the most applicable for acoustic impact 
analysis at Berths 11, 12, and 13. For the purposes of this IHA, 
however, we will conservatively assume that drilling has identical 
source levels to vibratory driving when calculating zones of influence. 
This includes instances where drilling is underway in the absence of 
any concurrent driving.
    As part of Year 2 activities, concurrent work utilizing a vibratory 
hammer during drilling operations is possible. This potential 
concurrent activity could occur during installation of the rock sockets 
for approximately 16 days. The vibratory hammer may be working to 
install SOE sheets or H-Pile as the drilling work is being conducted. 
Under concurrent driving conditions, the Navy will use the larger of 
the two source level values to calculate size of entire ensonified 
area. Since the vibratory source level is greater than the level 
associated with drilling, it will be utilized.
    With limited source level data available for vibratory pile 
extraction of 25-inch steel sheet piles, NMFS used the same values for 
both vibratory installation and extraction assuming that the two 
activities would produce

[[Page 3326]]

similar source levels if water depth, pile size, and equipment remain 
constant.
    When NMFS Technical Guidance (2016) was published, in recognition 
of the fact that ensonified area/volume could be more technically 
challenging to predict because of the duration component in the new 
thresholds, an User Spreadsheet was developed that includes tools to 
help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which will result in some degree of 
overestimate of Level A take. However, these tools offer the best way 
to predict appropriate isopleths when more sophisticated 3D modeling 
methods are not available, and NMFS continues to develop ways to 
quantitatively refine these tools, and will qualitatively address the 
output where appropriate. For stationary sources pile driving, NMFS 
User Spreadsheet predicts the closest distance at which, if a marine 
mammal remained at that distance the whole duration of the activity, it 
would not incur PTS. Inputs used in the User Spreadsheet and the 
resulting isopleths are reported below in Table 8 and Table 9.

                                          Table 8--User Spreadsheet Input for Level A Isopleth PTS Calculations
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                               25'' Steel Sheet
       User Spreadsheet Input          14'' Steel H impact      14'' Steel vibro       15'' Timber vibro            vibro                 Drilling
--------------------------------------------------------------------------------------------------------------------------------------------------------
Spreadsheet Tab Used...............  E.1) Impact pile        A) Non-Impulsive,       A) Non-Impulsive,      A) Non-Impulsive,      A) Non-Impulsive,
                                      driving.                Stationary,             Stationary,            Stationary,            Stationary,
                                                              Continuous.             Continuous.            Continuous.            Continuous.
Source Level (Single Strike/shot     171 SEL...............  148 rms...............  150 rms..............  163..................  154 rms.
 SEL).
Weighting Factor Adjustment (kHz)..  2.....................  2.5...................  2.5..................  2.5..................  2.5.
Number of strikes per pile.........  160...................  NA....................  NA...................  NA...................  NA.
Activity duration within 24-h        4 piles...............  4 hours...............  4 hours..............  4 hours..............  8 hours.
 period OR number of piles per day.
Propagation (xLogR)................  15LogR................  15LogR................  15LogR...............  15LogR...............  15LogR.
Distance of source level             10....................  10....................  16...................  10...................  10.
 measurement (meters)+.
--------------------------------------------------------------------------------------------------------------------------------------------------------


  Table 9--User Spreadsheet Output for Level A Isopleth and Ensonified
                          Area PTS Calculations
------------------------------------------------------------------------
                                               PTS Isopleth
                                ----------------------------------------
          Source Type              High- Frequency
                                      Cetaceans        Phocid Pinnipeds
------------------------------------------------------------------------
14'' Steel H Impact............  140 m..............  63 m.
14'' Steel Vibro...............  3.5 m..............  1.4 m.
15'' Timber Vibro..............  7.5 m..............  1.9 m.
25'' Steel Sheet Vibro.........  34.6 m.............  14.2 m.
Drilling (8 hours/day) within    54.9 m.............  22.6 m.
 Shutdown Zone * utilizing 163
 dB rms value.
------------------------------------------------------------------------
                          Daily Ensonified Area
------------------------------------------------------------------------
14'' Steel H Impact............  0.0615 km\2\.......  0.0125 km\2\.
14'' Steel H Vibro.............  38.46 m\2\.........  6.15 m\2\.
15'' Timber Vibro..............  179.9 m\2\.........  11.33 m\2\.
25'' Steel Sheet Vibro.........  0.0038 km\2\.......  0.00062 km\2\.
Drilling (8 hours/day) within    0.0095 km\2\.......  0.0016 km\2\.
 Shutdown Zone * utilizing 163
 dB rms value.
------------------------------------------------------------------------
* While 154 dB rms is shown for drilling activity source level, take
  estimates and calculation of the ensonified area have been based on
  163 dB rms (vibratory drilling) as these activities may run
  concurrently.

    Using the same source level and transmission loss inputs discussed 
in the Level A isopleths section above, the Level B distance was 
calculated for both impact and vibratory driving (Table 10). The 
attenuation distance for impact hammer use associated with the 
installation of the sister pile/support pile with a source level of 182 
dB rms resulted in an isopleth of 293 meters (m). The attenuation 
distance for vibratory hammer use with a source level of 163 dB rms 
resulted in an isopleth of 7.35 kilometers (km). The Level B area 
associated with the 120 dB re 1 [mu]Pa (rms) isopleth for vibratory 
driving and which is used in the take calculations is 0.9445 square 
kilometers (km\2\). Note that these attenuation distances are based on 
sound characteristics in open water. The project area is located in a 
river surrounded by topographic features. Therefore, the actual 
attenuation distances are constrained by numerous land features and 
islands. As such, the maximum distance for the Level B isopleth during 
vibratory driving and drilling is approximately 1.4 km.

[[Page 3327]]



              Table 10--Pile-Driving Sound Exposure Distances (In-Water) Level B Zone of Influence
----------------------------------------------------------------------------------------------------------------
                                      Behavioral thresholds
         Drilling activity              for cetaceans and      Propagation model       Attenuation distance to
                                            pinnipeds                                         threshold
----------------------------------------------------------------------------------------------------------------
Vibratory Hammer...................  120 dB rms............  Practical Spreading    7.35 km (4.57 mi).
                                                              Loss.
Impact Hammer (rms)................  160 dB rms............  Practical Spreading    293 m (961 ft).
                                                              Loss.
----------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence

    In this section, we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. For all species, the best scientific information 
available was considered for use in the marine mammal take assessment 
calculations. Density information was taken from the Navy Marine Mammal 
Density Database as shown in Table 11. (Craine 2015; Krause 2015). 
These data are generally used for broad-scale offshore activities; 
however, due to a lack of any other data within the general project 
area, these data are presented as the best available data for the 
Piscataqua River.

          Table 11--Marine Mammal Species Potentially Present in the Piscataqua River Near the Shipyard
----------------------------------------------------------------------------------------------------------------
                                                                      Approximate density in the vicinity of the
                                     Relative         Season(s) of     project area (individuals per km\2\) \1\
            Species               occurrence in        occurrence    -------------------------------------------
                                 Piscataqua River                       Winter     Spring     Summer      Fall
----------------------------------------------------------------------------------------------------------------
Harbor Porpoise Gulf of Maine/  Occasional use...  Spring to Fall        1.2122     1.1705     0.7903     0.9125
 Bay of Fundy stock.                                (April to
                                                    December) \2\.
Gray Seal Western North         Common...........  Year-round.......     0.2202     0.2202     0.2202     0.2202
 Atlantic stock.
Harbor Seal Western North       Common...........  Year-round.......     0.1998     0.1998     0.1998     0.1998
 Atlantic stock.
Harp Seal Western North         Rare.............  Winter to Spring      0.0125     0.0125     0.0125     0.0125
 Atlantic stock.                                    (January-May).
Hooded Seal Western North       Rare.............  Winter to Spring         N/A        N/A        N/A        N/A
 Atlantic stock.                                    (January-May).
----------------------------------------------------------------------------------------------------------------
Notes:
\1\ Density data are taken from the Navy Marine Species Density Database (Crain 2015; Krause 2015).
\2\ Densities shown for all seasons, even when species are unlikely to occur in the river.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    The following assumptions are made when estimating potential 
incidences of take:
     All marine mammal individuals potentially available are 
assumed to be present within the relevant area, and thus incidentally 
taken;
     An individual can only be taken once during a 24-h period;
     While up to 16 days of concurrent driving/drilling could 
occur, NMFS will conservatively assume that there are zero (0) days 
resulting in a total of 100 pile driving/drilling days; and
     Exposures to sound levels at or above the relevant 
thresholds equate to take, as defined by the MMPA.
    In this case, the estimation of marine mammal takes uses the 
following calculation:

Exposure estimate = n * ZOI * days of total activity

Where:

n = density estimate used for each species/season.
ZOI = sound threshold ZOI area; the area encompassed by all 
locations where the SPLs equal or exceed the threshold being 
evaluated.

    The ZOI impact area is estimated using the relevant distances in 
Table 9 and Table 10, assuming that sound radiates from a central point 
in the water column at project site and taking into consideration the 
possible affected area due to topographical constraints of the action 
area (i.e., radial distances to thresholds are not always reached) as 
shown in Figure 6-1 in the application.
    There are a several reasons why estimates of potential incidents of 
take may be conservative, assuming that available density and estimated 
ZOI areas are accurate. We assume, in the absence of information 
supporting a more refined conclusion, that the output of the 
calculation represents the number of individuals that may be taken by 
the specified activity. In fact, in the context of stationary 
activities such as pile driving and in areas where resident animals may 
be present, this number more realistically represents the number of 
incidents of take that may accrue to a smaller number of individuals. 
While pile driving can occur any day throughout the period of validity, 
and the analysis is conducted on a per day basis, only a fraction of 
that time (typically a matter of hours on any given day) is actually 
spent pile driving. The potential effectiveness of mitigation measures 
in reducing the number of takes is typically not quantified in the take 
estimation process. For these reasons, these take estimates may be 
conservative.

Harbor Porpoise

    Harbor porpoises may be present in the project area year-round. 
Based on density data from the Navy Marine Species Density Database, 
their presence is highest in winter and spring, decreases in summer, 
and slightly increases in fall. However, in general, porpoises are 
known to occasionally occur in the river. Average density for the 
predicted seasons of occurrence was used to determine abundance of 
animals that could be present in the area for exposure, using the 
equation abundance = n * ZOI. Estimated abundance estimate for harbor 
porpoises was 0.96 animals generated from the equation (0.9445 km\2\ 
Level B ensonified area *1.02 animals/km\2\). The number of Level B 
harbor porpoise exposures within the ZOIs is (100 days * 0.96

[[Page 3328]]

animals/day) is 96. Therefore, NMFS authorizes 96 Level B takes of 
harbor porpoise.
    The injury zone for harbor porpoise was calculated to extend to a 
radius of 140 m from impact driven piles and a maximum of 55 m from 
vibratory or drilling activity. A 75 m shutdown zone is planned (see 
``Mitigation''); therefore, the area between the 75 m and 140 m 
isopleths is where Level A take may occur during impact hammer use. The 
area of the 75 m shutdown zone was subtracted from the full Level A 
injury zone to obtain the Level A take zone of 0.0132 km\2\. The 
density of harbor porpoises is estimated at 1.02 harbor porpoises/
km\2\. Using the density of harbor porpoises potentially present (1.02 
animal/km\2\) and the area of the Level A take zone, less than one 
(0.1218 mammals) harbor porpoise a day was estimated to be exposed to 
injury over the nine days of impact pile driving. In the Federal 
Register notice for the proposed IHA (82 FR 56791; November 30, 2017), 
NMFS had proposed to authorize a single Level A take of harbor 
porpoise. However, as part of the monitoring requirements under the 
existing IHA, the Navy observed two harbor porpoises traveling together 
in August 2017. In order to avoid shutdown and delay associated with 
exceeding take limits, NMFS will authorize the Level A take of two 
harbor porpoises.

Harbor Seal

    Harbor seals may be present year-round in the project vicinity, 
with constant densities throughout the year. Based on local anecdotal 
data, harbor seals are the most common pinniped in the Piscataqua River 
near the Shipyard. Average density for the predicted seasons of 
occurrence was used to determine abundance of animals that could be 
present in the area for exposure, using the equation abundance = n * 
ZOI. Abundance for harbor seals were 0.19/day. (Average year-round 
density = 0.1998). Therefore, Level B harbor seal exposures within the 
ZOI is (100 days * 0.19 animals/day) would be up to 19 Level B 
exposures of harbor seals within the ZOI. As described above in the 
gray seal section, however, the modeling of estimated takes may be 
underestimated. The data from the preliminary monitoring report 
indicated 120 re 1 [mu]Pa (rms) Level B exposures of harbor seals over 
73 work days resulting in 1.64 takes per day (120 takes/73 days). 
Therefore, NMFS is proposing to authorize 164 Level B harbor seal takes 
(1.64 takes/day * 100 days).
    The injury zone for harbor seals was calculated to extend a radius 
of 63 m from impact driven piles and 14m for vibratory hammer use. The 
injury zone for drilling activity is estimated at 23 m. The Level A 
injury zone is within the shutdown zone, therefore no injurious takes 
of harbor seals are estimated to occur. However, as stated above for 
the gray seal take request, this may be an underestimate. The Navy has 
requested four Level A takes of harbor seal to coincide with the same 
number of Level A takes requested in Year 1. Preliminary monitoring 
report results support authorization of Level A take as one harbor seal 
was detected within 50 m of drilling activity. Therefore, NMFS is 
conservatively proposing four Level A takes of harbor seals so that 
operations will not have to be suspended due to exceeding authorized 
Level A takes.

Gray Seal

    Gray seals are less common in the Piscataqua River than the harbor 
seal. Average density for the predicted seasons of occurrence was used 
to determine abundance of animals that could be present in the area for 
exposure, using the equation abundance = n * ZOI. The estimated 
abundance for gray seals is 0.21/day (average year-round density = 
0.2202). Therefore, the number of Level B gray seal exposures within 
the ZOI is (100 days * 0.21 animals/day) resulting in up to 21 Level B 
exposures of gray seals within the ZOI.
    However, current monitoring data indicate that this could be an 
underestimate. While there could be 21 Level B and 0 Level A takes for 
gray seal during construction activity monitoring of the zones, 
observations of gray seals have shown 18 Level B exposures over 73 days 
of activity through October 27, 2017. This comes out to 0.246 exposures 
per day (18/73 = 0.246). Therefore, the Navy has requested and NMFS is 
proposing to authorize 25 gray seal takes (0.246 takes/day * 100 days) 
under the IHA.
    The injury zone for gray seals was calculated to extend to a radius 
of 63m for impact driven piles and 14m for vibratory hammer use. The 
injury zone for drilling is estimated at 23m from the activity. The 
injury zone for impact, vibratory and drilling activity remains within 
the shutdown zone of 75m for impact hammer use and 55 m for vibratory 
driving and drilling (see ``Mitigation''). These zones were utilized 
during Year 1. Based on these calculations and continued implementation 
of the shutdown zones, no injurious takes of gray seals are estimated 
to occur. The Navy, however, requests authorization of two Level A 
takes of gray seal to coincide with the same number of Level A takes 
requested in Year 1. This is partially supported by data collected in 
the preliminary Year 1 IHA monitoring report in which observers 
recorded one gray seal within 50 m of drilling activity. Because 
animals were observed within the shutdown zone during Year 1, NMFS is 
conservatively proposing authorization of two Level A gray seal takes, 
so that operations will not have to be suspended if animals 
unexpectedly occur in the Level A zones.

Harp Seal

    Harp seals may be present in the project vicinity during the winter 
and spring, from January through February. In general, harp seals are 
much rarer than the harbor seal and gray seal in the Piscataqua River. 
These animals are conservatively assumed to be present within the 
underwater Level B ZOI during each day of in-water pile driving. 
Average density for the predicted seasons of occurrence was used to 
determine abundance of animals that could be present in the area for 
exposure, using the equation abundance = n * ZOI. Abundance for harp 
seals was 0.014/day (average year-round density = 0.0125). The number 
of Level B harp seal exposures within the ZOI is (100 days * 0.0125 
animals/day) resulting in approximately 1 Level B exposure. In the 
Federal Register notice for the proposed IHA (82 FR 56791; November 30, 
2017), NMFS had proposed to authorize a single Level B take of harp 
seal. Although rare, harp seals have been known to occur in this area. 
Therefore, in order to avoid shutdown and delay associated with 
exceeding take limits, NMFS will authorize the Level B take of five 
harp seals. This conservatively assumes that one harp seal could be 
taken during each of the five months that construction activities would 
take place.
    The injury zone for harp seals was calculated to extend a radius of 
63 m from impact driven piles and 14 m for vibratory hammer use. The 
injury zone for drilling is estimated at 23 m from the activity. These 
isopleths are within the shutdown zones and NMFS. Therefore, no Level A 
take is authorized as shown in Table 13.

Hooded Seal

    In the Federal Register notice for the proposed IHA (82 FR 56791; 
November 30, 2017), NMFS did not propose to authorize take of any 
hooded seals. This was based on the fact that hooded seals are rare in 
this area and none were recorded under the 2017 IHA monitoring 
requirements. In general, hooded seals are much rarer than the

[[Page 3329]]

harbor seal and gray seal in the Piscataqua River. Anecdotal sighting 
information indicates that two hooded seals were observed from the 
Shipyard in August 2009, but no other observations have been recorded. 
Information on the average density for hooded seals was not available. 
In order to guard against unauthorized take of hooded seals, NMFS will 
authorize the Level B take of five hooded seals. This conservatively 
assumes that during each of the five months of construction one hooded 
seal could be taken by Level B harassment.
    The injury zone for hooded seals was calculated to extend a radius 
of 63m from impact driven piles and 14m for vibratory hammer use. The 
injury zone for drilling is estimated at 23 m from the activity. As 
shown in Table 13, these isopleths are within the shutdown zones and, 
therefore, no Level A take is authorized.

Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting such 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned); the likelihood of effective implementation (probability 
implemented as planned); and
    (2) the practicability of the measures for applicant 
implementation, which may consider such things as cost and impact on 
operations.

Mitigation for Marine Mammals and Their Habitat

    The mitigation strategies described below are similar to those 
required and implemented under the first IHA associated with this 
project. In addition to the measures described later in this section, 
the Navy would conduct briefings between construction supervisors and 
crews, marine mammal monitoring team, and Navy staff prior to the start 
of all pile driving activity, and when new personnel join the work, in 
order to explain responsibilities, communication procedures, marine 
mammal monitoring protocol, and operational procedures.
    The following measures would apply to the Navy's mitigation through 
shutdown and disturbance zones:
    Time Restrictions--Pile driving/removal (vibratory as well as 
impact) will only be conducted during daylight hours so that marine 
mammals can be adequately monitored to determine if mitigation measures 
are to be implemented.
    Establishment of Shutdown zone--During pile driving and removal, 
shutdown zones shall be established to prevent injury to marine mammals 
as determined under acoustic injury thresholds. During all pile driving 
and removal activities, regardless of predicted sound pressure levels 
(SPLs), the entire shutdown zone will be monitored to prevent injury to 
marine mammals from their physical interaction with construction 
equipment during in-water activities. The shutdown zone during impact 
driving will extend to 75 m for all authorized species. The shutdown 
during vibratory driving and drilling will extend to 55 m for all 
authorized species. Pile driving and removal operations will cease if a 
marine mammal approaches the shutdown zone. Pile driving and removal 
operations will restart once the marine mammal is visibly seen leaving 
the zone or after 15 minutes have passed with no sightings.
    Establishment of Level A Harassment Zone--The Level A harassment 
zone is an area where animals may be exposed to sound levels that could 
result in PTS injury. The primary purpose of the Level A zone is 
monitoring for documenting incidents of Level A harassment. The Level A 
zones will extend from the 75 m shutdown zone out to 140 m for harbor 
porpoises. Animals observed in the Level A harassment zone will be 
recorded as potential Level A takes.
    Establishment of Disturbance/Level B Harassment Zone--During pile 
driving and removal, the Level B zone shall include areas where the 
underwater SPLs are anticipated to equal or exceed the Level B 
harassment criteria for marine mammals (160 dB rms isopleths for impact 
pile driving, 120 re 1 [mu]Pa (rms) isopleth for vibratory pile-driving 
and drilling). The Level B zone will extend out to 293 m for impact 
driving and 7.35 km during vibratory driving and drilling and will 
include all waters in the sight line of the driving or drilling 
operation not constrained by land.
    Shutdown Zone During Other In-water Construction or Demolition 
Activities--During all in-water construction or demolition activities 
having the potential to affect marine mammals, in order to prevent 
injury from physical interaction with construction equipment, a 
shutdown zone 10 m will be implemented to ensure marine mammals are not 
present within this zone. These activities could include, but are not 
limited to: (1) The movement of a barge to the construction site, or 
(2) the removal of a pile from the water column/substrate via a crane 
(i.e., a ``dead pull'').
    Soft Start for Impact Pile Driving--The use of a soft-start 
procedure is believed to provide additional protection to marine 
mammals by providing a warning and/or giving marine mammals a chance to 
leave the area prior to the hammer operating at full capacity. The 
project will use soft-start techniques recommended by NMFS for impact 
pile driving. Soft start must be conducted at beginning of day's 
activity and at any time impact pile driving has ceased for more than 
30 minutes. If an impact hammer is used, contractors are required to 
provide an initial set of three strikes from the impact hammer at 40 
percent energy, followed by a 1-minute waiting period, then two 
subsequent 3-strike sets.
    Monitoring Protocols--Monitoring would be conducted before, during, 
and after pile driving 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. Observations made outside the 
shutdown zone will not result in shutdown; that pile segment would be 
completed without cessation, unless the animal approaches or enters the 
shutdown zone, at which point all pile driving activities would be 
halted. Monitoring will take place from 15

[[Page 3330]]

minutes prior to initiation through 30 minutes post-completion of pile 
driving activities.
    Monitoring will be conducted by one marine mammal observer (MMO) on 
one-third of driving days who will monitor the Level A harassment and 
shutdown zone during all pile-driving operations. Two MMOs shall 
monitor the Level A, Level B, and shutdown zones during two-thirds of 
pile-driving days. The Navy will extrapolate data collected by two MMOs 
during two-thirds of monitoring days and calculate total Level B take 
for all pile-driving days.
    Prior to the start of pile driving activity, the shutdown zone will 
be monitored for 15 minutes to ensure that it is clear of marine 
mammals. Pile driving will only commence once observers have declared 
the shutdown zone clear of marine mammals; animals will be allowed to 
remain in the shutdown zone (i.e., must leave of their own volition) 
and their behavior will be monitored and documented. The shutdown zone 
may only be declared clear when the entire shutdown zone is visible 
(i.e., when not obscured by dark, rain, fog, etc.).
    Drilling/pile driving activity shall not be conducted when weather/
observer conditions do not allow for adequate sighting of marine 
mammals. In the unlikely event of conditions that prevent the visual 
detection of marine mammals, such as heavy fog, activities with the 
potential to result in Level A or Level B harassment will not be 
initiated. Impact pile driving already underway would be curtailed, but 
vibratory driving may continue if driving has already been initiated on 
a given pile. Driving of additional piles by any means will not be 
allowed until all zones are visible. However, in the event of an unsafe 
work environment if conditions prevent detection of marine mammals 
during impact pile driving and the pile currently being driven is not 
stable enough for activities to cease, impact pile driving would 
continue to get the single pile to stability.
    If a marine mammal approaches or enters the shutdown zone during 
the course of pile driving operations, activity will be halted and 
delayed until either the animal has voluntarily left and been visually 
confirmed beyond the shutdown zone or 15 minutes have passed. 
Monitoring will be conducted throughout the time required to drive a 
pile and for 30 minutes following the conclusion of pile driving.
    Based on our evaluation of the applicant's proposed measures NMFS 
has determined that the required mitigation measures provide the means 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
action area. Effective reporting is critical both to compliance as well 
as ensuring that the most value is obtained from the required 
monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     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.

Previous Monitoring Report

    The Navy submitted a preliminary monitoring report covering the 
period between April 18, 2017 and October 27, 2017. This period does 
not cover all pile driving activities. Therefore, the Navy will submit 
a final report after the authorization period ends. During this period, 
piles were installed using vibratory hammer, the impact hammer, and 
drilling. Work was conducted over 73 days. Drilling has accounted for 
98.8% of the total noise-generating time spent on installation/
extraction activities at the Shipyard; vibratory activity occurred 
during 1% of the total time; and impact driving took place <1% of the 
total time. During this time, observers noted 142 occurrences of marine 
mammals within designated zones, with all but one occurring within the 
Level B harassment zone as shown in Table 12. Monitoring of all zones 
occurred on every drilling day.

                            Table 12--Summary of 2017 Takes Through October 28, 2018
----------------------------------------------------------------------------------------------------------------
                                                              Level A                         Level B
                     Species                     ---------------------------------------------------------------
                                                      Actual        Authorized        Actual        Authorized
----------------------------------------------------------------------------------------------------------------
Harbor porpoise.................................               0              10               3             160
Harbor seal.....................................               1               4             120             312
Gray seal.......................................               0               2              18             156
Harp seal.......................................               0               0               0               5
Hooded seal.....................................               0               0               0               5
----------------------------------------------------------------------------------------------------------------


[[Page 3331]]

Visual Monitoring

    The Navy will be required to conduct visual marine mammal 
monitoring during pile driving activities. Observers shall record all 
incidents of marine mammal occurrence, regardless of distance from 
activity, and shall document any behavioral reactions in concert with 
distance from piles being driven or removed. Pile driving activities 
include the time to install or remove a single pile or series of piles, 
as long as the time elapsed between uses of the pile driving equipment 
is no more than 30 minutes.
    A minimum of two MMOs will be on location during all pile driving 
activities. They will be placed at the best vantage point(s) 
practicable. MMOs may be stationed on an elevated platform. MMOs will 
monitor for marine mammals and implement shutdown/delay procedures when 
applicable by calling for the shutdown to equipment operators. MMOs 
will scan the waters within each monitoring zone activity using big-eye 
binoculars, hand held binoculars, spotting scopes and visual 
observation. Monitoring distances will be measured with range finders 
and bearing to animals shall be determined using a compass.
    The observers will be trained on the observation zones, potential 
species, how to observe, and how to fill out the data sheets by the 
Navy Natural Resources Manager prior to any pile-driving activities. 
The supervisory observer will be a trained biologist; additional 
observers will be trained by that supervisor as needed.
    Shutdown and Level A zones must be monitored at all times by one 
MMO with no other duties or responsibilities. A second MMO will be 
required to monitor Level B zones on two-thirds of driving days. The 
following additional measures apply to visual monitoring during all 
pile driving activities
     Independent observers (i.e., not construction personnel) 
are required;
     At least one observer must have prior experience working 
as an observer;
     Other observers (that do not have prior experience) may 
substitute education (undergraduate degree in biological science or 
related field) or training for experience;
     NMFS will require submission and approval of observer 
resumes.
    Qualified observers are trained biologists with the following 
minimum 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;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates and times when in-water construction 
activities were suspended to avoid potential incidental injury from 
construction sound of marine mammals observed within a defined shutdown 
zone; and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities or 60 days prior to the issuance of any subsequent IHA for 
this project, whichever comes first. It will include an overall 
description of work completed, a narrative regarding marine mammal 
sightings, and associated marine mammal observation data sheets, and 
extrapolated Level B take counts. Specifically, the report must 
include:
     Date and time that monitored activity begins or ends;
     Sediment characteristics/type;
     Construction activities occurring during each observation 
period;
     Weather parameters (e.g., percent cover, visibility);
     Water conditions (e.g., sea state, tide state);
     Species, numbers, and, if possible, sex and age class of 
marine mammals;
     Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
     Distance from pile driving activities to marine mammals 
and distance from the marine mammals to the observation point;
     Locations of all marine mammal observations; and
     Other human activity in the area.
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA 
(if issued), such as serious injury or mortality, the Navy will 
immediately cease the specified activities and report the incident to 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the Northeast/Greater Atlantic Regional Stranding 
Coordinator. The report would include the following information:
     Description of the incident;
     Environmental conditions (e.g., Beaufort sea state, 
visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with the Navy to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. The Navy would not be able 
to resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that the Navy discovers an injured or dead marine 
mammal, and the lead MMO determines that the cause of the injury or 
death is unknown and the death is relatively recent (e.g., in less than 
a moderate state of decomposition as described in the next paragraph), 
the Navy would immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
and the Northeast/Greater Atlantic Regional Stranding Coordinator. The 
report would include the same information identified in the paragraph 
above. Activities would be able to continue while NMFS reviews the 
circumstances of the incident. NMFS would work with the Navy to 
determine whether modifications in the activities are appropriate.
    In the event that the Navy discovers an injured or dead marine 
mammal and the lead MMO determines that the injury or death is not 
associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), the Navy would report the incident 
to the Chief of the Permits and Conservation Division, Office of 
Protected Resources, NMFS, and the Northeast/Greater Atlantic Regional 
Stranding Coordinator within 24 hours of the discovery. The Navy would 
provide photographs, video footage (if

[[Page 3332]]

available) or other documentation of the stranded animal sighting to 
NMFS and the Marine Mammal Stranding Network.

Hydroacoustic Monitoring

    The Navy will continue to implement its in situ acoustic monitoring 
efforts in 2018. Specifically, data would be collected during vibratory 
installation of 20 sheet piles and impact installation of 4 H-piles, 
during drilling activities on one day, and during one day of drilling 
with concurrent vibratory driving. However, concurrent activity is so 
infrequent it is not likely to occur for a full day. Navy shall measure 
sound intensity at 10 m from the source pile, at the modeled limits of 
the Level A and Level B zones, and at intermediate points between 10m 
and the 160 dB and 120 dB re 1 [mu]Pa (rms) isopleths. For all piles 
required to be monitored, 100 percent of the data from each pile will 
be analyzed and included in the reported results, including ``soft 
starts'' of impact hammers. For each combination of pile type and 
hammer, the monitoring locations will be chosen to maximize coverage of 
the ZOI based on the number of piles scheduled for monitoring for a 
given timeframe. See the Navy's Acoustic Monitoring Plan for additional 
information. A final report shall be submitted to NMFS within 30 days 
of completing the verification monitoring. Results from the 2017 
Hydroacoustic Monitoring Report may be found in Appendix A of the 
application. Data from the 2017 and 2018 hydroacoustic monitoring 
reports may be used to revise isopleths delineating harassment zones. 
Any revisions would be subject to NMFS' review and approval.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS's implementing 
regulations (54 FR 40338; September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, ongoing sources of human-caused mortality, or 
ambient noise levels).
    Pile driving, pile extraction and drilling activities associated 
with the Navy project have the potential to injure, disturb or displace 
marine mammals. Specifically, the planned activities may result in 
Level B harassment (behavioral disturbance) for all species authorized 
for take from underwater sound generated during pile driving. Level A 
harassment in the form of PTS may also occur to limited numbers of 
three marine mammal species. Potential takes could occur if individuals 
of these species are present in the ensonified zone when pile driving 
and removal occurs.
    No serious injury or mortality is anticipated given the nature of 
the activities and measures designed to minimize the possibility of 
injury to marine mammals. The potential for these outcomes is minimized 
through the construction method and the implementation of the planned 
mitigation measures. Specifically, vibratory driving and drilling will 
be the primary methods of installation (impact driving will occur for 
only 1.5 hours over 84-100 days). During impact driving, implementation 
of soft start and shutdown zones significantly reduces any possibility 
of injury. Given sufficient ``notice'' through use of soft start (for 
impact driving), marine mammals are expected to move away from a sound 
source that is annoying prior to it becoming potentially injurious. 
Conditions at the Shipyard offer MMOs clear views of the shutdown 
zones, enabling a high rate of success in implementation of shutdowns 
to avoid injury.
    The Navy's planned activities are highly localized. A small portion 
of the Piscataqua River may be affected which is only a subset of the 
ranges of species for which take is authorized. The project is not 
expected to have significant adverse effects on marine mammal habitat. 
No important feeding and/or reproductive areas for marine mammals are 
known to be near the project area. Project-related activities may cause 
some fish to leave the area of disturbance, thus temporarily impacting 
marine mammals' foraging opportunities in a limited portion of the 
foraging range. However, since the area of the habitat range utilized 
by each species that may be affected is relatively small, the impacts 
to marine mammal habitat are not expected to cause significant or long-
term negative consequences.
    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. The pile driving activities analyzed 
here are similar to, or less impactful than, numerous construction 
activities conducted in other similar locations, which have taken place 
with no reported injuries or mortality to marine mammals, and no known 
long-term adverse consequences from behavioral harassment. Repeated 
exposures of individuals to levels of sound that may cause Level B 
harassment are unlikely to result in permanent hearing impairment or to 
significantly disrupt foraging behavior. Level B harassment will be 
reduced through use of mitigation measures described herein.
    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:
     No mortality or serious injury is anticipated or 
authorized;
     The area of potential impacts is highly localized;
     No adverse impacts to marine mammal habitat;
     The absence of any significant habitat within the project 
area, including rookeries, or known areas or

[[Page 3333]]

features of special significance for foraging or reproduction;
     Anticipated incidences of Level A harassment would be in 
the form of a small degree of PTS to a limited number of animals;
     Anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior;
     Very few individuals are likely to be affected by project 
activities (<0.01 percent of population for all authorized species); 
and
     The anticipated efficacy of the required mitigation 
measures 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 required monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the construction 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.

  Table 13--Estimated Number of Exposures and Percentage of Stocks That May Be Subjected to Level A and Level B
                                                   Harassment
----------------------------------------------------------------------------------------------------------------
                                               Authorized take          Total Level A
               Species                --------------------------------   and Level B         Population (%)
                                           Level B         Level A          takes
----------------------------------------------------------------------------------------------------------------
Harbor porpoise Gulf of Maine/Bay of               96               2              98  <0.01
 Fundy stock.
Gray Seal Western North Atlantic                   25               2              27  <0.01
 stock.
Harbor Seal Western North Atlantic                164               4             168  <0.01
 stock.
Harp Seal Western North Atlantic                    5               0               5  <0.01
 stock.
Hooded Seal Western North Atlantic                  5               0               5  <0.01
 stock.
----------------------------------------------------------------------------------------------------------------

    Table 13 illustrates the number of animals that could be exposed to 
Level A and Level B harassment from work associated with the waterfront 
improvement project. The analysis provided indicates that authorized 
takes account for <0.01 percent of the populations of the stocks that 
could be affected. These are small numbers of marine mammals relative 
to the sizes of the affected species and population stocks under 
consideration.
    Based on the analysis contained herein of the planned activity 
(including the required mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS finds that small numbers of 
marine mammals will be taken relative to the population size of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

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

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat.
    No incidental take of ESA-listed species is authorized or expected 
to result from this activity. Therefore, NMFS has determined that 
consultation under section 7 of the ESA is not required for this 
action.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in CE B4 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 and signed a Categorical Exclusion memo in 
January 2018.

Authorization

    NMFS has issued an IHA to the Navy for the potential harassment of 
small numbers of five marine mammal species incidental to the 
Waterfront Improvement Project at the Portsmouth Naval Shipyard in 
Kittery, Maine, provided the previously mentioned mitigation, 
monitoring and reporting requirements are incorporated.

    Dated: January 19, 2018.
Donna S. Wieting,
Director, Office of Protected Resources,National Marine Fisheries 
Service.
[FR Doc. 2018-01306 Filed 1-23-18; 8:45 am]
 BILLING CODE 3510-22-P