Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Portsmouth Naval Shipyard Dry Dock 1 Modification and Expansion, 24476-24490 [2019-10980]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 84, Number 102 (Tuesday, May 28, 2019)]
[Notices]
[Pages 24476-24490]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-10980]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XG851


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Portsmouth Naval Shipyard Dry Dock 
1 Modification and Expansion

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 we have issued an incidental harassment authorization (IHA) to the 
U.S. Navy (Navy) to take small numbers of marine mammals, by 
harassment, incidental to Portsmouth Naval Shipyard Dry Dock 1 
modification and expansion in Kittery, Maine.

DATES: This authorization is effective from October 1, 2019, through 
September 30, 2020.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as the issued IHA, may be obtained 
online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems 
accessing these documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

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

Summary of Request

    On November 1, 2018, NMFS received a request from the Navy for an 
IHA to take marine mammals incidental to modification and expansion of 
dry dock 1 at Portsmouth Naval Shipyard in Kittery, Maine. The 
application was deemed adequate and complete on March 11, 2019. The 
Navy's request is for take of harbor porpoises, harbor seals, gray 
seals, harp seals, and hooded seals by Level B harassment and Level A 
harassment. Neither the Navy nor NMFS expects serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.
    NMFS previously issued two IHAs to the Navy for waterfront 
improvement work in 2017 (81 FR 85525; November 28, 2016) and 2018 (83 
FR 3318; January 24, 2018). The Navy complied with all the requirements 
(e.g., mitigation, monitoring, and reporting) of the previous IHAs and 
information regarding their monitoring results may be found in the 
Estimated Take section.
    NMFS has issued an IHA to the Navy for the take by Level A and 
Level B harassment of harbor porpoise (Phocoena phocoena), harbor seal 
(Phoca vitulina), gray seal (Halichoerus grypus), harp seal (Pagophilus

[[Page 24477]]

groenlandicus), and hooded seal (Cystophora cristata) incidental to its 
dry dock modification and expansion project.

Description of Proposed Activity

Overview

    The purpose of the Navy's construction project 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 modify and expand Dry Dock 1 at the Portsmouth 
Naval Shipyard by constructing two new dry docking positions capable of 
servicing Virginia class submarines within the super flood basin of the 
dry dock.
    The in-water portion of the dock modification and expansion work 
includes:
    [ssquf] Construction of the temporary structure for south closure 
wall;
    [ssquf] Construction of the super flood basin of the dry dock; and
    [ssquf] Extension of portal crane rail and utilities.
    Construction activities that could affect marine mammals are 
limited to in-water pile driving and removal activities.

Dates and Duration

    Construction activities are expected to begin in July 2019. In-
water construction activities are expected to begin in October 2019, 
with an estimated total of 212 days for pile driving and pile removal. 
All in-water construction work will be limited to daylight hours.

Specific Geographic Region

    The Shipyard is located in the Piscataqua River in Kittery, Maine. 
The Piscataqua River originates at the boundary of Dover, New 
Hampshire, and Elliot, Maine. The river flows in a southeasterly 
direction for 13 miles before entering Portsmouth Harbor and emptying 
into the Atlantic Ocean. The lower Piscataqua River is part of the 
Great Bay Estuary system and varies in width and depth. Many large and 
small islands break up the straight-line flow of the river as it 
continues toward the Atlantic Ocean. Seavey Island, the location of the 
proposed action, is located in the lower Piscataqua River approximately 
547 yards from its southwest bank, 219 yards from its north bank, and 
approximately 2.5 miles upstream from the mouth of the river.
    A map of the Portsmouth Naval Shipyard dock expansion action area 
is provided in Figure 1 below, and is also available in Figures 2 to 4 
in the IHA application.
    Water depths in the proposed project area range from 21 feet (ft) 
to 39 ft at Berths 11, 12, and 13. Water depths in the lower Piscataqua 
River near the proposed project area range from 15 ft in the shallowest 
areas to 69 ft in the deepest areas. The river is approximately 3,300 
ft wide near the proposed project area, measured from the Kittery 
shoreline north of Wattlebury Island to the Portsmouth shoreline west 
of Peirce Island. The furthest direct line of sight from the proposed 
project area would be 0.8 mile to the southeast and 0.26 mile to the 
northwest.

[[Page 24478]]

[GRAPHIC] [TIFF OMITTED] TN28MY19.000

Detailed Description of Specific Activity

    Under the planned action, the expansion and modification would 
occur as multiple construction projects. Prior to the start of 
construction, the entrance to Dry Dock 1 would be dredged to previously 
permitted maintenance dredge limits. This dredging effort is required 
to support the projects and additional project-related dredging would 
occur intermittently throughout the proposed action. Since dredging and 
disposal activities would be slow-moving and generate low noise levels, 
NMFS and the Navy do not consider its effects as likely to rise the 
level of take of marine mammals. Therefore, these activities are not 
further discussed in this document.
    The proposed 2019 through 2020 activities include pile driving 
(vibratory and impact) and rock drilling associated with construction 
of the super flood basin and Berth 2 improvements of the dry dock. The 
action will take place in and adjacent to Dry Dock 1 in the Controlled 
Industrial Area (CIA) that occupies the western extent of the 
Portsmouth Naval Shipyard.

[[Page 24479]]

    To begin the project, a super flood basin will be created in front 
of the entrance of Dry Dock 1 by constructing closure walls that span 
from Berth 1 to Berth 11B. The super flood basin would operate like a 
navigation lock type structure: Artificially raising the elevation of 
the water within the basin and dry dock above the tidally controlled 
river in order to lift the submarines to an elevation where they can be 
safely transferred into the dry dock without the use of buoyancy assist 
tanks. The super flood basin would be located between Berths 1 and 11 
and extend approximately 580 ft from the existing outer seat of the dry 
dock (approximately 175 ft beyond the waterside end of Berth 1). The 
super flood basin would consist of three primary components: South 
closure wall, entrance structure, and west closure wall. The closure 
wall would be approximately 320 ft long and have an opening for a 
caisson gate. The Dry Dock 3 caisson would be repurposed for use in the 
new closure wall. A weir structure or discharge pipe would be built 
into the closure wall or incorporated into the modified caisson to 
control over-topping and ensure the super flood elevation, which is the 
minimum water elevation required to provide sufficient depths and 
clearance to safely support transit of Los Angeles class submarines 
into Dry Dock 1, through the entire super flood evolution. The gross 
area of the super flood basin would be approximately 152,000 square 
feet (ft\2\) (3.5 acres).
    Concrete components for the closure walls, caisson seat, and sill 
would be cast in place or be pre-cast off-site then floated or hauled 
into place, as appropriate. The closure walls would be equipped with 
winches and mooring hardware on either side of the basin entrance to 
assist with vessel docking, and to support berthing of the caisson gate 
while not in place. Electrical utilities would be provided to support 
lighting along the closure wall and meet the electrical requirements of 
the caisson gate. Mooring hardware and electrical utilities would also 
support the berthing of ships force barges at the south closure wall. 
Ships force barges are where a group of sailors live and work during 
the overhaul. The south closure wall would consist of two, 70-ft 
diameter sheet pile cells that would be connected together and to the 
point of Berths 1 and 2 by interconnecting arcs. The sheeting for the 
two cells would be driven to bedrock to make up the shell of the 
structure south of the caisson and seat. By installing the sheets to 
bedrock, the cells would provide a barrier to exfiltration. Each of the 
cells would be filled with mass concrete and topped with a reinforced 
concrete cap that would act as the deck to the structure. To provide 
corrosion protection from the marine environment, a concrete facing 
would extend down the exterior of the sheets to below mudline. A 
sacrificial (i.e., does not provide structural support) sheet pile wall 
would be installed outboard of the structural sheets and would remain 
for the life of the structure.
    Before the closure walls are constructed, modifications to Berth 1 
and Berth 11 are required. Improvements along Berth 1 includes driving 
steel sheet piles to create a bulkhead outboard of the existing quay 
wall, and placing concrete within the void between the sheet piles and 
the existing quay wall. This sheet pile bulkhead would provide a more 
impervious fa[ccedil]ade than the existing granite block quay wall to 
reduce water exfiltration from within the basin. The sheet pile 
bulkhead would be equipped with a concrete curb that would increase the 
height of Berth 1 by approximately 1 ft to an elevation of 15.6 ft 
above mean low-low-water (MLLW). To accommodate the super flood 
elevation improvements along Berth 11, bedrock grouting below the 
bulkhead from the west closure wall to the northwest corner of the 
basin would be installed to mitigate exfiltration along the berth. The 
stormwater drainage system at Berth 1 would be rerouted to a new 
outfall at the east end of Berth 2. The existing storm drain outfalls 
at Berth 11 within the limits of the basin have valves to prevent 
backflow of seawater into the storm drain collection system during 
super flood operations. The storm drain outlet piping would be modified 
to ensure landside drainage during super flood is accommodated.
    Construction of the basin closure wall would bisect the existing 
Berth 11B resulting in loss of a fitting-out pier. As such, Berth 2 
would replace Berth 11B for submarine outfitting. To accommodate this 
function, the existing fender system on Berth 2 would be relocated and 
expanded to accommodate fitting-out activities on the berth. 
Approximately 4,000 ft\2\ (surface area) of additional fender panel 
would be required, including 3,550 ft\2\ (surface area) below MLLW. The 
new fender panels would be approximately 6 inches (0.5 ft) thick and 
their installation below MLLW would result in a total fill volume of 
approximately 65 cubic yard. No in-water pile driving would be required 
at Berth 2 to support pier outfitting.
    Construction phasing would be required to minimize impacts on 
critical dry dock operations. Five notional construction phases were 
identified of which the first three would occur during the 2019 to 2020 
period. This phasing schedule could change due to fleet mission 
requirements and boat schedules. The first phase of construction would 
occur when a boat is present and would be limited to site 
reconnaissance, field measurements, contractor submittals and general 
mobilization activities. Phase 2 would include construction of the 
southern closure wall and caisson seat foundation; Berth 1 and Berth 11 
(A and B) improvements; Dry Dock 1 utility improvements; and dredging. 
Upland construction activities would include work on the Dry Dock 1 
gallery improvements and commencement of the portal crane rail 
extension. Phase 3 would include construction of the west closure wall, 
caisson seat float-in, and additional Dry Dock 1 utility gallery 
improvements. Only the caisson seat float-in portion of Phase 3 would 
occur during year 1. Six temporary dolphins, comprised of eight, 14-
inch H-Piles, would be installed to assist with float-in and placement 
of the caisson seat.
    Overall, the construction work is estimated to take approximately 
12 months to complete, of which pile driving/extraction/drilling would 
take 212 days.
    A summary of in-water pile driving activity is provided in Table 1.

                                                  Table 1--Summary of In-Water Pile Driving Activities
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                                                                    Pile size
             Pile purpose                      Pile type             (inch)         Pile drive method       Total piles      Piles/day       Work days
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Temporary structure..................  Steel H.................              14  Vibratory..............              32               2              16
                                                                                 Impact.................                               2
Sheet pile wall along Berth 1........  Steel sheet.............              24  Vibratory..............             320              12              27
                                                                                 Impact.................                              12

[[Page 24480]]

 
South Closure wall construction......  Steel sheet.............              18  Vibratory..............             310              12              31
                                                                                 Impact.................                              12
                                       Steel H pile removal....              14  Vibratory..............              32               8               4
                                       Steel sheet.............              24  Vibratory..............              52              12               5
                                                                                 Impact.................                              12
                                       Steel H.................              14  Vibratory..............              17               1              17
                                                                                 Impact.................                               1
                                       Steel sheet.............              24  Vibratory..............             280              12              24
                                                                                 Impact.................                              12
                                       Steel pipe casing.......              96  Down hole..............              10             0.5              32
Caisson seat float-in................  Steel pipe..............              36  Vibratory..............              48               1              48
                                                                                 Impact.................              48               1
Elevated deck support................  Steel pipe..............              16  Vibratory..............               8               1               8
                                                                                 Impact.................               8
                                      ------------------------------------------------------------------------------------------------------------------
    Total............................  ........................  ..............  .......................           1,558  ..............             212
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    Prescribed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Mitigation and 
Monitoring and Reporting).

Comments and Responses

    A notice of NMFS' proposal to issue an IHA was published in the 
Federal Register on April 4, 2019 (84 FR 13252). During the 30-day 
public comment period, NMFS received a comment letter from the Marine 
Mammal Commission (Commission). Specific comments and responses are 
provided below.
    Comment 1: Commission recommends that NMFS (1) ensure the Navy is 
aware of the requirements of the final incidental harassment 
authorization, particularly the reporting requirements for the marine 
mammal and hydroacoustic monitoring reports, and (2) require that the 
Navy provide the information that is missing but was required in both 
the 2017 and 2018 monitoring reports.
    Response: NMFS has contacted the Navy and emphasized the importance 
of following IHA requirements concerning marine mammal monitoring and 
hydroacoustic monitoring reports. NMFS has requested and received 
marine mammal monitoring information and data sheet required under the 
2017 and 2018 IHAs.
    Comment 2: The Commission recommends that NMFS authorize at least 
five harbor seal takes per day partitioned in the same proportions for 
Level A and B harassment as included in Table 8 of the Federal Register 
notice.
    Response: NMFS accepted the Commission's recommendation and 
recalculated harbor seal harassment. The revised take analysis is 
provided later in this document and is included in the IHA NMFS issued.
    Comment 3: The Commission recommends that NMFS require the Navy to 
implement full-time monitoring of the various Level A and B harassment 
zones during all proposed activities.
    Response: In the IHA issued to the Navy, NMFS requires the Navy to 
implement full-time monitoring of all Level A harassment zones during 
all in-water pile driving activities. However, for Level B harassment, 
NMFS has authorized the employment of a minimum of two PSOs employed on 
two-thirds of driving days due to the extent of the pile driving 
activities. NMFS believes that the number of marine mammals potentially 
affected by Level B harassment can be extrapolated from the two-thirds 
of the monitoring days.
    Comment 4: The Commission recommends that NMFS refrain from 
implementing its proposed renewal process and instead use abbreviated 
Federal Register notices and reference existing documents to streamline 
the IHA process. If NMFS adopts the proposed renewal process, the 
Commission recommends that NMFS provide the Commission and the public a 
legal analysis supporting its conclusion that the process is consistent 
with section 101(a)(5)(D) of the MMPA.
    Response: The notice of the proposed IHA expressly notifies the 
public that under certain, limited conditions an applicant could seek a 
renewal IHA for an additional year. The notice describes the conditions 
under which such a renewal request could be considered and expressly 
seeks public comment in the event such a renewal is sought. Additional 
reference to this solicitation of public comment has recently been 
added at the beginning of the Federal Register notices that consider 
renewals, requesting input specifically on the possible renewal itself. 
NMFS appreciates the streamlining achieved by the use of abbreviated 
Federal Register notices and intends to continue using them for 
proposed IHAs that include minor changes from previously issued IHAs, 
but which do not satisfy the renewal requirements. However, we believe 
our method for issuing renewals meets statutory requirements and 
maximizes efficiency. However, importantly, such renewals will be 
limited to circumstances where: The activities are identical or nearly 
identical to those analyzed in the proposed IHA; monitoring does not 
indicate impacts that were not previously analyzed and authorized; and, 
the mitigation and monitoring requirements remain the same, all of 
which allow the public to comment on the appropriateness and effects of 
a renewal at the same time the public provides comments on the initial 
IHA. NMFS has, however, modified the language for future proposed IHAs 
to clarify that all IHAs, including renewal IHAs, are valid for no more 
than one year and that the agency will consider only one renewal for a 
project at this time. In addition, notice of issuance or denial of a 
renewal IHA will be published in the Federal Register, as they are for 
all IHAs. The option for issuing renewal IHAs has been in NMFS' 
incidental take regulations since 1996.

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution

[[Page 24481]]

and habitat preferences, and behavior and life history, of the 
potentially affected species. Additional information regarding 
population trends and threats may be found in NMFS's Stock Assessment 
Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general 
information about these species (e.g., physical and behavioral 
descriptions) may be found on NMFS's website (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species with expected potential for occurrence in 
the Piscataqua River in Kittery, Maine, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and ESA and potential biological removal (PBR), where known. 
For taxonomy, we follow Committee on Taxonomy (2018). PBR is defined by 
the MMPA as the maximum number of animals, not including natural 
mortalities, that may be removed from a marine mammal stock while 
allowing that stock to reach or maintain its optimum sustainable 
population (as described in NMFS's SARs). While no mortality is 
anticipated or authorized here, PBR and annual serious injury and 
mortality from anthropogenic sources are included here as gross 
indicators of the status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS's stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. Atlantic Marine Mammal SARs. All values presented in Table 
2 are the most recent available at the time of publication and are 
available in the 2017 SARs (Hayes et al., 2018) and draft 2018 SARs 
(available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports).

                                    Table 2. Marine Mammals With Potential Presence Within the Proposed Project Area
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                                                                                                        Stock abundance
                                                                                   ESA/MMPA status;     (CV, Nmin, most                     Annual M/SI
            Common name                Scientific name             Stock          strategic (Y/N) \1\   recent abundance        PBR             \3\
                                                                                                          survey) \2\
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                                         Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales)
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                                                             Family Phocoenidae (porpoises)
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Harbor porpoise...................  Phocoena phocoena....  Gulf of Maine/Bay of  -; N................             79,833             706             255
                                                            Fundy.                                        (0.32, 61,415)
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                                                         Order Carnivora--Superfamily Pinnipedia
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                                                             Family Phocidae (earless seals)
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Harbor seal.......................  Phoca vitulina.......  Western North         -; N................             75,834           2,006             345
                                                            Atlantic.                                     (0.15, 66,884)
Gray seal.........................  Halichoerus grypus...  Western North         -; N................             27,131           5,688           1,389
                                                            Atlantic.                                     (0.19, 23,158)
Harp seal.........................  Pagophilus             Western North         -; N................     \4\ 7,411,000;              NA         225,687
                                     groenlandicus.         Atlantic.                                           (NA, NA)
Hooded seal.......................  Cystophora cristata..  Western North         -; N................        \5\ 593,500              NA           1,680
                                                            Atlantic.                                           (NA, NA)
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region#reports. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ Based on the latest estimates made in 2012 in Bay of Fundy (Hayes et al. 2018).
\5\ Based on the latest estimates made in 2005 (Hammill and Stenson 2006).

    All species that could potentially occur in the proposed action 
area are included in Table 2. More detailed descriptions of marine 
mammals in the Portsmouth Naval Shipyard project area is provided in 
the Federal Register notice for the proposed IHA (84 FR 13252; April 4, 
2019). Therefore, it is not repeated here.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups.

[[Page 24482]]

Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 3.

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

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Five marine mammal species (one cetacean and four pinniped (all phocid) 
species) have the reasonable potential to co-occur with the proposed 
survey activities. Please refer to Table 2. Of the cetacean species 
that may be present, the harbor porpoise is classified as a high-
frequency cetacean.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take section, and the Proposed Mitigation section, to draw 
conclusions regarding the likely impacts of these activities on the 
reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.
    Potential impacts to marine mammals from the Portsmouth Naval 
Shipyard modification and expansion project are from noise generated 
during in-water pile driving activities. Detailed analysis of the 
impacts is provided in the Federal Register notice for the proposed IHA 
(84 FR 13252; April 4, 2019). Therefore, it is not repeated here.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as any act of 
pursuit, torment, or annoyance, which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would primarily be by Level B harassment, as noise 
generated from in-water pile driving (vibratory and impact) has the 
potential to result in disruption of behavioral patterns for individual 
marine mammals. There is also some potential for auditory injury (Level 
A harassment) to result for some harbor porpoises and harbor and gray 
seals. The proposed mitigation and monitoring measures are expected to 
minimize the severity of such taking to the extent practicable.
    As described previously, no mortality is anticipated or proposed to 
be authorized for this activity. Below we describe how the take is 
estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities,

[[Page 24483]]

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 (e.g., 
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms) 
for impulsive and/or intermittent (e.g., impact pile driving) sources.
    The Navy's Portsmouth Naval Shipyard modification and expansion 
project includes the use of continuous (vibratory pile driving and 
down-the-hole driving by rock 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 (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The Navy's Portsmouth Naval Shipyard 
modification and expansion includes the use of impulsive (impact pile 
driving) and non-impulsive (vibratory pile driving and down-the-hole 
driving) sources.
    These thresholds are provided in the table below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS' 2018 Technical Guidance, which may be accessed at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

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

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
Source Levels
    The project includes impact pile driving, vibratory pile driving 
and pile removal, and drilling for down-the-hole piling activities. 
Source levels of pile driving activities are based on reviews of 
measurements of the same or similar types and dimensions of piles 
available in the literature. Based on this review, the following source 
levels are assumed for the underwater noise produced by construction 
activities:
     Vibratory driving of 36-inch steel piles would be assumed 
to generate a root-mean-squared (rms) sound pressure level (SPL) and 
sound exposure level (SEL) of 175 dB re 1 [mu]Pa\2\-sec at 10 m, based 
on the averaged source level of the same type of pile reported by 
California Department of Transportation (Caltrans) in a pile driving 
source level compendium document (Caltrans, 2015);
     Impact driving of 36-inch steel piles would be assumed to 
generate an instantaneous peak SPL (SPLpk) of 209 dB re 1 
[mu]Pa, an rms SPL of 198 dB re 1 [mu]Pa, and single-strike SEL 
(SELss) of 183 dB re 1 [mu]Pa\2\-sec at the 10 m distance, 
based on the weighted average of similar pile driving at the Bangor 
Naval Base, Naval Base Point Loma, CA (NAVFAC 2012), Washington State 
Department of Transportation (WSDOT) Anacortes Ferry Terminal (Laughlin 
2012), and WSDOT Mukilteo Ferry Terminal (Laughlin 2007) that was 
analyzed in the Navy New London Submarine Base dock construction IHA 
application (NAVFAC 2016);
     Vibratory removal of 14-inch steel H-piles is 
conservatively assumed to have rms SPL and SEL values of 158 dB re 1 
[mu]Pa\2\-sec at 10 m distance based on a relatively large set of 
measurements from the vibratory installation of 14-inch H-piles 
reported by Caltrans (2015);
     Impact driving of 14-inch steel H-piles is assumed to 
generate a SPLpk of 194 dB re 1[mu]Pa, rms SPL of 177 dB re 
1 [mu]Pa, and SELss of 162 dB re 1 [mu]Pa\2\-sec at 10 m 
distance based on measurements on the same piles conducted during the 
Portsmouth Naval Shipyard construction in 2018 (NAVFAC Mid-Atlantic, 
2018);
     Vibratory driving of 18- and 24-inch sheet pile is assumed 
to have an rms SPL and SEL of 163 dB re 1 [mu]Pa\2\-sec based on 
measurements conducted at 10 m by the NAVFAC Mid-Atlantic (2018);
     Impact driving of 18- and 24-inch sheet pile is assumed to 
have a SPLpk of 205 dB re 1 [mu]Pa, an rms SPL of 190 dB re 
1 [mu]Pa, and a SELss of 180 dB re 1 [mu]Pa\2\-sec based on 
data reported in the Caltrans compendium (Caltrans 2015) for the same 
piles;
     Down-the-hole drilling of 96-inch steel pile casing is 
assumed to have an rms SPL and SEL of 166.2 dB re 1 [mu]Pa\2\-sec based 
on measurements conducted at the Kodiak Ferry Terminal, AK (Austin et 
al., 2016);
     Vibratory pile driving of 16-inch steel pile is assumed to 
have an rms SPL

[[Page 24484]]

and SEL of 162 dB re 1 [mu]Pa\2\-sec based on measurements for the same 
piles at Naval Base Kitsap at Bangor, WA (Illingworth and Rodkin 2013); 
and
     Impact driving of 16-inch steel pile is assumed to have a 
SPLpk of 182 dB re 1 [mu]Pa, an rms SPL of 163 dB re 1 
[mu]Pa, and a SELss of 158 dB re 1 [mu]Pa\2\-sec based on 
levels from the same pile reported in the Caltrans compendium (Caltrans 
2015).
    A summary of source levels from different pile driving activities 
is provided in Table 5.

                                                 Table 5--Summary of In-Water Pile Driving Source Levels
                                                                  [At 10 m from source]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  SEL, dB re 1   SPLrms, dB   SPLpk, dB
                Method                   Pile type/size (inch)   [micro]Pa\2\-      re 1         re 1       Measured distance             Origin
                                                                       s         [micro]Pa    [micro]Pa
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory pile driving...............  Steel, 36-inch..........           175           175           NA  10 m.................  Caltrans.
Impact pile driving..................  Steel, 36-inch..........           183           198          209  10 m.................  Navy New London.
Vibratory pile driving...............  Steel H, 14-inch........           158           158           NA  10 m.................  Caltrans.
Impact pile driving..................  Steel H, 14-inch........           162           177          194  10 m.................  Navy Portsmouth SSV.
Vibratory pile driving...............  Steel sheet, 24-inch &             163           163           NA  10 m.................  NAVFAC Atlantic Fleet.
                                        18-inch.
Impact pile driving..................  Steel sheet, 24-inch &             180           190          205  10 m.................  Caltrans.
                                        18-inch.
Down-the-hole piling.................  Steel pile casing 96-            166.2         166.2           NA  10 m.................  Kodiak, AK.
                                        inch.
Vibratory pile driving...............  Steel, 16-inch..........           162           162           NA  10 m.................  Naval Base Kitsap
                                                                                                                                  Bangor, WA.
Impact pile driving..................  Steel, 16-inch..........           158           163          182  10 m.................  Caltrans.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    These source levels are used to compute the Level A harassment 
zones and to estimate the Level B harassment zones. For Level A 
harassment zones, since the peak source levels for are below the injury 
thresholds, cumulative SEL were used to do the calculations using the 
NMFS acoustic guidance (NMFS 2018).
    The Level B harassment distances for pile driving are calculated 
using practical spreading with source levels provided in Table 5. 
Ensonified areas (A) are calculated using the following equation.
[GRAPHIC] [TIFF OMITTED] TN28MY19.001

where R is the harassment distance.

    For some pile driving activities, up to two vibratory hammers could 
be operating concurrently. Given that specific arrangements of 
concurrent pile driving are unknown until pile driving starts, there is 
no way to calculate the exact distances and combined source levels. For 
Level B harassment, the impact zone distance from concurrent pile 
driving from more than one hammer would only be affected if the driving 
methods are vibratory and/or drilling running concurrently. In most 
cases, the vibratory distance would win out due to the higher source 
level, if they are closely located. If they are some distance apart 
(<30m), separate zones from each hammer can be used.
    For Level A harassment, energy summation is impossible to predict. 
However, the current method that treats each source independently, 
i.e., with its own Level A harassment zone, is more conservative than 
one larger zone assuming combined sources.
    Finally, the relatively small, closed area of the construction site 
means that ensonified zones (particularly for Level B harassment) will 
be capped to a maximum distance of 10,000 m (6.2 miles) due to landmass 
interception in the surrounding area. For this reason, the maximum area 
that could be ensonified by noise from pile driving activities is 
mapped at 0.8544 km\2\ (0.33 square miles) Therefore, all calculated 
Level B harassment areas that are larger than 0.8544 km\2\ based on 
Equation (1) are corrected to this maximum value.
    When the original 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, NMFS developed a User Spreadsheet that includes 
tools to help predict a simple isopleth that can be used in conjunction 
with marine mammal density or occurrence to help predict takes. We note 
that because of some of the assumptions included in the methods used 
for these tools, we anticipate that isopleths produced are typically 
going to be overestimates of some degree, which may result in some 
degree of overestimate of Level A harassment take. However, these tools 
offer the best way to predict appropriate isopleths when more 
sophisticated 3D modeling methods are not available, and NMFS continues 
to develop ways to quantitatively refine these tools, and will 
qualitatively address the output where appropriate. For stationary 
sources such as in-water vibratory and impact 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 (pile driving 
duration or number of strikes for each pile, and the number of piles 
installed or removed per day), and the resulting isopleths are reported 
below in Table 6.
    For all calculations, the results based on SELss are 
larger than SPLpk, therefore, distances calculated using 
SELss are used to calculate the areas. The Level A 
harassment areas are calculated using the same Equation (1), with 
corrections to reflect the largest possible area of 0.8544 km\2\ if the 
calculation value was larger.
    The modeled distances to Level A and Level B harassment zones for 
various marine mammals are provided in Table 6. As discussed above, the 
only marine mammals that could occur in the vicinity of the project 
area are harbor porpoise (high-frequency cetacean) and four species of 
true seals (phocid).

[[Page 24485]]



                                                    Table 6--Distances and Areas of Harassment Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                Level A harassment                  Level B harassment
                                                                                 -----------------------------------------------------------------------
                                                                  Duration (sec)        HF cetacean               Phocid
                Pile type, size & driving method                   or # strikes  ------------------------------------------------                Area
                                                                     per pile                    Area                    Area     Dist.  (m)    (km\2\)
                                                                                   Dist. (m)    (km\2\)   Dist.  (m)    (km\2\)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory drive 14-inch H-pile (2 pile/day).....................             300         1.9       0.000         0.8       0.000     3,414.5      *0.854
Impact drive 14-inch H-pile (2 pile/day)........................             300        33.7       0.036        15.1       0.007       135.9        0.06
Vibratory drive 24-inch sheet pile (12 pile/day)................             300        13.7       0.001         5.6       0.001     7,356.4       0.854
Impact drive 18-inch & 24-inch sheet pile (12 pile/day).........             300        1763       0.854         792       0.854        1000       0.854
Vibratory removal 14-inch H-pile (8 pile/day)...................             300         4.9       0.001           2       0.000        3414       0.854
Vibratory drive 14-inch H-pile (1 pile/day).....................             300         1.2       0.000         0.5       0.000        3414       0.854
Impact drive 14-inch H-pile (1 pile/day)........................             300        21.2       0.001         9.5       0.000       135.9        0.06
Down-hole drive 96-inch steel casing (0.5 pile/day).............          28,800        56.5       0.010        23.2       0.002       10000       0.854
Vibratory drive 36-inch steel pipe pile (1 pile/day)............             300        16.5       0.001         6.8       0.000       10000       0.854
Impact drive 36-inch steel pipe pile (1 pile/day)...............             300       533.1       0.439       239.5       0.123     3,414.5       0.854
Vibratory drive 16-inch steel pipe pile (1 pile/day)............             300         2.2       0.000         0.9       0.000        6310       0.854
Impact drive 16-inch steel pipe pile (1 pile/day)...............             300        11.5       0.000         5.2       0.000        15.8       0.008
--------------------------------------------------------------------------------------------------------------------------------------------------------
* 0.854 km\2\ is the maximum ensonified area in the project area due to landmass that blocks sound propagation.

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.
    Marine mammal density estimates for harbor porpoise and gray seal 
are derived based on marine mammal monitoring during 2017 and 2018 
(CIANBRO 2018a, b). Density values were calculated from visual 
sightings of all marine mammals divided by the monitoring days (a total 
of 154 days) and the total ensonified area in the 2017 and 2018 
activities (0.8401 km\2\). Details used for calculations are provided 
in Table 7 and described below.
    For harbor seal, due to its high abundance, based on discussion 
with the Marine Mammal Commission, we have determined it more 
appropriate to use the maximum observation of 5 seals from marine 
mammal monitoring during 2017 and 2018 (CIANBRO 2018a, b) as the basis 
for estimating potential takes per day. The take number is then 
calculated by multiplying the assumed daily take by total in-water 
construction days in the 2019 season (212 days). Further, takes by 
Level A and Level B harassment of harbor seals are prorated based on 
the Level A and Level B harassment ensonified areas.

Table 7--Marine Mammal Sightings and Resulting Density in the Vicinity of Portsmouth Naval Shipyard Project Area
----------------------------------------------------------------------------------------------------------------
                                                                                                      Density
                     Species                       2017 sighting   2018 sighting  Total sighting   (animal/day/
                                                     (96 days)       (58 days)                        km\2\)
----------------------------------------------------------------------------------------------------------------
Harbor porpoise.................................               3               2               5            0.04
Harbor seal.....................................             199             122             321          * 2.48
Gray seal.......................................              24               2              26            0.20
----------------------------------------------------------------------------------------------------------------
* For harbor seals, due to its much higher abundance and habituation to human activities, its maximum
  observation (5 seals/day) was used for take calculation (see below).

    During construction monitoring in the project area 3 harbor 
porpoise were sighted between April and December of 2017 and 2 harbor 
porpoise were sighted in early August of 2018. From this data, density 
of harbor porpoise for the largest ensonified zone was determined to be 
0.04/km\2\. Sightings of gray seals were recorded during monthly 
surveys conducted in 2017 as well as during Berth 11 construction 
monitoring in 2017 and 2018. Density for harbor seals was based on the 
Berth 11 Waterfront Improvement Construction monitoring and was 
determined to be 0.20/km\2\. Harbor seals are the most common pinniped 
in the Piscataqua River near the Shipyard. Sightings of this species 
were recorded during monthly surveys conducted in 2017 as well as 
during Berth 11 construction monitoring in 2017 and 2018. Density for 
harbor seals based on the Berth 11 Waterfront Improvement Construction 
was determined to be 2.48/km\2\. However, due to its much higher 
occurrence in the project area, based on discussion with the 
Commission, its maximum daily sighting was used in take calculation 
(see below).
    Hooded and harp seals are much rarer than the harbor and gray seals 
in the Piscataqua River, and no density information for these two 
species is available. To date, marine mammal monitoring during prior 
IHAs has not recorded a sighting of a hooded or harp seal in the 
project area.

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    For marine mammals with calculated density information (i.e., 
harbor porpoise and gray seal), in general,

[[Page 24486]]

estimated Level A harassment take numbers are calculated using the 
following equation:
[GRAPHIC] [TIFF OMITTED] TN28MY19.002

    For Level B harassment takes, the same equation (2) was used but 
then adjusted by subtracting the estimated Level A harassment takes. 
However, the estimated takes are calculated assuming the animals are 
uniformly distributed within the action area without forming groups. In 
reality, porpoises and seals are often active in small groups of two to 
three animals. Therefore, to account for potential group encounters 
during the construction activity, the estimated Level B harassment 
takes are adjusted upwards to form the basis of the proposed take 
authorization.
    For harbor seal, the total calculated take is calculated using the 
following equation:
[GRAPHIC] [TIFF OMITTED] TN28MY19.003

    Further, the Level A and Level B harassment takes are prorated 
based on the sizes of Level A and Level B harassment zones.
    NMFS authorized one Level B harassment take per month each of a 
hooded seal and a harp seal for the Berth 11 Waterfront Improvements 
Construction project in 2018. The Navy is requesting authorization of 
one Level B harassment take each of hooded seal and harp seal per month 
of construction from January through May when these species may occur 
(Total of 5 Level B harassment takes for each species).
    A summary of estimated and proposed takes is presented in Table 8.

                             Table 8--Estimated and Proposed Takes of Marine Mammals
----------------------------------------------------------------------------------------------------------------
                                                     Estimated       Estimated       Estimated        Percent
                     Species                       Level A take    Level B take     total take    population (%)
----------------------------------------------------------------------------------------------------------------
Harbor porpoise.................................               5              12              17            0.02
Harbor seal.....................................             284             776            1060            1.40
Gray seal.......................................              25              35              60            0.21
Hooded seal.....................................               0               5               5            0.00
Harp seal.......................................               0               5               5            0.00
----------------------------------------------------------------------------------------------------------------

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. 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, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
1. Time Restriction
    Work would occur only during daylight hours, when visual monitoring 
of marine mammals can be conducted.
2. Establishing and Monitoring Level A and Level B Harassment Zones and 
Shutdown Zones
    Before the commencement of in-water construction activities, which 
include impact pile driving, vibratory pile driving and pile removal, 
and down-the-hole drilling, the Navy shall establish Level A harassment 
zones where received underwater SELcum could cause PTS (see 
Table 6 above).
    The Navy shall also establish Level B harassment zones where 
received underwater SPLs are higher than 160 dBrms re 1 
[micro]Pa for impulsive noise sources (impact pile driving) and 120 
dBrms re 1 [micro]Pa for continuous noise sources (vibratory 
pile driving, pile removal, and down-the-hole drilling) (see Table 6 
above).
    The Navy shall establish shutdown zones based on Level A harassment 
distance up to a maximum of 110 m for harbor porpoise and 50 m for 
seals from

[[Page 24487]]

the source but no less than 10 m for all in-water construction work. A 
summary of the shutdown zones is provided in Table 9.

   Table 9--Shutdown Distances for Various Pile Driving Activities and
                      Marine Mammal Hearing Groups
------------------------------------------------------------------------
                                               Shutdown distance (m)
    Pile type, size & driving method     -------------------------------
                                            HF cetacean       Phocid
------------------------------------------------------------------------
Vibratory drive 14-inch H-pile (2 pile/               10              10
 day)...................................
Impact drive 14-inch H-pile (2 pile/day)              35              20
Vibratory drive 24-inch sheet pile (12                20              10
 pile/day)..............................
Impact drive 18-inch & 24-inch sheet                 110              50
 pile (12 pile/day).....................
Vibratory removal 14-inch H-pile (8 pile/             10              10
 day)...................................
Vibratory drive 14-inch H-pile (1 pile/               10              10
 day)...................................
Impact drive 14-inch H-pile (1 pile/day)              25              10
Down-the-hole drilling 96-inch steel                  60              25
 casing (0.5 pile/day)..................
Vibratory drive 36-inch steel pipe pile               20              10
 (1 pile/day)...........................
Impact drive 36-inch steel pipe pile (1              110              50
 pile/day)..............................
Vibratory drive 16-inch steel pipe pile               10              10
 (1 pile/day)...........................
Impact drive 16-inch steel pipe pile (1               15              10
 pile/day)..............................
------------------------------------------------------------------------

    If marine mammals are found within the exclusion zone, pile driving 
of the segment would be delayed until they move out of the area. If a 
marine mammal is seen above water and then dives below, the contractor 
would wait 15 minutes. If no marine mammals are seen by the observer in 
that time it can be assumed that the animal has moved beyond the 
exclusion zone.
    If pile driving of a segment ceases for 30 minutes or more and a 
marine mammal is sighted within the designated exclusion zone prior to 
commencement of pile driving, the observer(s) must notify the pile 
driving operator (or other authorized individual) immediately and 
continue to monitor the exclusion zone. Operations may not resume until 
the marine mammal has exited the exclusion zone or 15 minutes have 
elapsed since the last sighting.
3. Shutdown Measures
    The Navy shall implement shutdown measures if a marine mammal is 
detected within the shutdown zones listed in Table 9.
    Further, the Navy shall implement shutdown measures if the number 
of authorized takes for any particular species reaches the limit under 
the IHA (if issued) and such marine mammals are sighted within the 
vicinity of the project area and are approaching the Level B harassment 
zone during in-water construction activities.
4. Soft Start
    The Navy shall implement soft start techniques for impact pile 
driving. The Navy shall conduct an initial set of three strikes from 
the impact hammer at 40 percent energy, followed by a 1-minute waiting 
period, then two subsequent three strike sets. Soft start shall be 
required for any impact driving, including at the beginning of the day, 
and at any time following a cessation of impact pile driving of thirty 
minutes or longer.
    Whenever there has been downtime of 30 minutes or more without 
impact driving, the contractor shall initiate impact driving with soft-
start procedures described above.
    Based on our evaluation of the required measures, NMFS has 
determined that the prescribed mitigation measures provide the means 
effecting the least practicable adverse impact on the affected species 
or stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Monitoring and Reporting

    In order to issue an IHA for an activity, Section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     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.

Monitoring Measures

    The Navy shall employ trained protected species observers (PSOs) to 
conduct marine mammal monitoring for its Portsmouth Naval Shipyard 
modification and expansion project. The purposes of marine mammal 
monitoring are to implement mitigation measures and learn more about 
impacts to marine mammals from the Navy's construction activities. The 
PSOs will observe and collect data on marine mammals in and around the 
project area for 30 minutes

[[Page 24488]]

before, during, and for 30 minutes after all pile removal and pile 
installation work.
Protected Species Observer Qualifications
    NMFS-approved PSOs shall meet the following requirements:
    1. Independent observers (i.e., not construction personnel) are 
required;
    2. At least one observer must have prior experience working as an 
observer;
    3. Other observers may substitute education (undergraduate degree 
in biological science or related field) or training for experience;
    4. Where a team of three or more observers are required, one 
observer should be designated as lead observer or monitoring 
coordinator. The lead observer must have prior experience working as an 
observer; and
    5. NMFS will require submission and approval of observer CVs.
Marine Mammal Monitoring Protocols
    The Navy shall conduct briefings between construction supervisors 
and crews and the PSO team prior to the start of all pile driving 
activities, and when new personnel join the work, in order to explain 
responsibilities, communication procedures, marine mammal monitoring 
protocol, and operational procedures. All personnel working in the 
project area shall watch the Navy's Marine Species Awareness Training 
video. An informal guide shall be included with the monitoring plan to 
aid in identifying species if they are observed in the vicinity of the 
project area.
    The Navy will monitor all Level A harassment zones and at least 
two-thirds of the Level B harassment zones before, during, and after 
pile driving activities. The Marine Mammal Monitoring Plan would 
include the following procedures:
     PSOs will be primarily located on docks and piers at the 
best vantage point(s) in order to properly see the entire shutdown 
zone(s);
     PSOs will be located at the best vantage point(s) to 
observe the zone associated with behavioral impact thresholds;
     During all observation periods, PSOs will use high-
magnification (25X), as well as standard handheld (7X) binoculars, and 
the naked eye to search continuously for marine mammals;
     Monitoring distances will be measured with range finders. 
Distances to animals will be based on the best estimate of the PSO, 
relative to known distances to objects in the vicinity of the PSO;
     Bearings to animals will be determined using a compass;
     Pile driving shall only take place when the shutdown zones 
are visible and can be adequately monitored. If conditions (e.g., fog) 
prevent the visual detection of marine mammals, activities with the 
potential to result in Level A harassment shall not be initiated. If 
such conditions arise after the activity has begun, impact pile driving 
would be halted but vibratory pile driving or extraction would be 
allowed to continue;
     At least two (2) PSOs shall be posted to monitor marine 
mammals during in-water pile driving and pile removal;
     Pre-Activity Monitoring:
    The shutdown zones will be monitored for 30 minutes prior to in-
water construction/demolition activities. If a marine mammal is present 
within a shutdown zone, the activity will be delayed until the 
animal(s) leaves the shutdown zone. Activity will resume only after the 
PSO has determined that, through sighting or by waiting 15 minutes, the 
animal(s) has moved outside the shutdown zone. If a marine mammal is 
observed approaching the shutdown zone, the PSO who sighted that animal 
will notify all other PSOs of its presence.
     During Activity Monitoring:
    If a marine mammal is observed entering the Level A or Level B 
harassment zones outside the shutdown zone, the pile segment being 
worked on will be completed without cessation, unless the animal enters 
or approaches the shutdown zone, at which point all pile driving 
activities will be halted. If an animal is observed within the 
exclusion zone during pile driving, then pile driving will be stopped 
as soon as it is safe to do so. Pile driving can only resume once the 
animal has left the shutdown zone of its own volition or has not been 
re-sighted for a period of 15 minutes.
     Post-Activity Monitoring:
    Monitoring of all Level A harassment zones and two-thirds of the 
Level B harassment zones will continue for 30 minutes following the 
completion of the activity.
Information Collection
    PSOs shall collect the following information during marine mammal 
monitoring:
     Date and time that monitored activity begins and ends for 
each day conducted (monitoring period);
     Construction activities occurring during each daily 
observation period, including how many and what type of piles driven;
     Deviation from initial proposal in pile numbers, pile 
types, average driving times, etc.;
     Weather parameters in each monitoring period (e.g., wind 
speed, percent cloud cover, visibility);
     Water conditions in each monitoring period (e.g., sea 
state, tide state);
     For each marine mammal sighting:
    [cir] Species, numbers, and, if possible, sex and age class of 
marine mammals;
    [cir] Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving activity;
    [cir] Location and distance from pile driving activities to marine 
mammals and distance from the marine mammals to the observation point; 
and
    [cir] Estimated amount of time that the animals remained in the 
Level B zone;
     Description of implementation of mitigation measures 
within each monitoring period (e.g., shutdown or delay);
     Other human activity in the area within each monitoring 
period
    To verify the required monitoring distance, the shutdown zones and 
harassment zones will be determined by using a range finder or hand-
held global positioning system device.

Reporting Measures

    The Navy is required to submit a draft monitoring report within 90 
days after completion of the construction work or the expiration of the 
IHA (if issued), whichever comes earlier. If Navy intends to renew the 
IHA (if issued) in a subsequent year, a monitoring report should be 
submitted no less than 60 days before the expiration of the current IHA 
(if issued). This report would detail the monitoring protocol, 
summarize the data recorded during monitoring, and estimate the number 
of marine mammals that may have been harassed. NMFS would have an 
opportunity to provide comments on the report, and if NMFS has 
comments, The Navy would address the comments and submit a final report 
to NMFS within 30 days.
    In addition, NMFS would require the Navy to notify NMFS' Office of 
Protected Resources and NMFS' Greater Atlantic Stranding Coordinator 
within 48 hours of sighting an injured or dead marine mammal in the 
construction site. The Navy shall provide NMFS and the Stranding 
Network with the species or description of the animal(s), the condition 
of the animal(s) (including carcass condition, if the animal is dead), 
location, time of first discovery, observed behaviors (if alive), and 
photo or video (if available).

[[Page 24489]]

    In the event that the Navy finds an injured or dead marine mammal 
that is not in the construction area, the Navy would report the same 
information as listed above to NMFS as soon as operationally feasible.

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).
    To avoid repetition, this introductory discussion of our analysis 
applies to all of the species listed in Table 2, given that the 
anticipated effects of the Navy's Portsmouth Naval Shipyard 
modification and expansion construction project activities involving 
pile driving and pile removal on marine mammals are expected to be 
relatively similar in nature. There is no information about the nature 
or severity of the impacts, or the size, status, or structure of any 
species or stock that would lead to a different analysis by species for 
this activity, or else species-specific factors would be identified and 
analyzed.
    Although some individual harbor porpoises and harbor and gray seals 
are estimated to experience Level A harassment in the form of PTS if 
they stay within the Level A harassment zone during the entire pile 
driving for the day, the degree of injury is expected to be mild and is 
not likely to affect the reproduction or survival of the individual 
animals. It is expected that, if hearing impairments occurs, most 
likely the affected animal would lose a few dB in its hearing 
sensitivity, which in most cases is not likely to affect its survival 
and recruitment. Hearing impairment that might occur for these 
individual animals would be limited to the dominant frequency of the 
noise sources, i.e., in the low-frequency region below 2 kHz. 
Nevertheless, as for all marine mammal species, it is known that in 
general these pinnipeds will avoid areas where sound levels could cause 
hearing impairment. Therefore it is not likely that an animal would 
stay in an area with intense noise that could cause severe levels of 
hearing damage.
    Under the majority of the circumstances, anticipated takes are 
expected to be limited to short-term Level B harassment. Marine mammals 
present in the vicinity of the action area and taken by Level B 
harassment would most likely show overt brief disturbance (startle 
reaction) and avoidance of the area from elevated noise levels during 
pile driving and pile removal. Given the limited estimated number of 
incidents of Level A and Level B harassment and the limited, short-term 
nature of the responses by the individuals, the impacts of the 
estimated take cannot be reasonably expected to, and are not reasonably 
likely to, rise to the level that they would adversely affect either 
species at the population level, through effects on annual rates of 
recruitment or survival.
    There are no known important habitats, such as rookeries or 
haulouts, in the vicinity of the Navy's proposed Portsmouth Naval 
Shipyard modification and expansion construction project. The project 
also is not expected to have significant adverse effects on affected 
marine mammals' habitat, including prey, as analyzed in detail in the 
Anticipated Effects on Marine Mammal Habitat section.
    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 is anticipated or authorized;
     Some individual marine mammals are anticipated to 
experience a mild level of PTS, but the degree of PTS is not expected 
to affect their survival;
     Most adverse effects to marine mammals are temporary 
behavioral harassment; and
     No biologically important area is present in or near the 
proposed construction area.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the proposed activity will have a negligible impact on all affected 
marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under section 101(a)(5)(A) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers and so, in practice, NMFS compares the number of 
individuals taken to the most appropriate estimation of abundance of 
the relevant species or stock in our determination of whether an 
authorization is limited to small numbers of marine mammals.
    The estimated takes are below 1.5 percent of the population for all 
marine mammals (Table 8).
    Based on the analysis contained herein of the proposed activity 
(including the prescribed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS finds that small numbers of 
marine mammals will be taken relative to the population size of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

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

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our 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

[[Page 24490]]

Categorical Exclusion B4 (incidental harassment authorizations with no 
anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
proposed IHA qualifies to be categorically excluded from further NEPA 
review.

Endangered Species Act (ESA)

    No incidental take of ESA-listed species is proposed for 
authorization or expected to result from this activity. Therefore, NMFS 
has determined that formal consultation under section 7 of the ESA is 
not required for this action.

Authorization

    As a result of these determinations, NMFS has issued an IHA to the 
Navy for conducting Portsmouth Naval Shipyard Dry Dock 1 Modification 
and Expansion in Kittery, Maine, between October 1, 2019, and September 
30, 2010, provided the previously prescribed mitigation, monitoring, 
and reporting requirements are incorporated.

    Dated: May 21, 2019.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2019-10980 Filed 5-24-19; 8:45 am]
 BILLING CODE 3510-22-P