Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Portsmouth Naval Shipyard Dry Dock 1 Modification and Expansion, 13252-13268 [2019-06537]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 84, Number 65 (Thursday, April 4, 2019)]
[Notices]
[Pages 13252-13268]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-06537]


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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; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to Portsmouth Naval 
Shipyard Dry Dock 1 modification and expansion in Kittery, Maine. 
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting 
comments on its proposal to issue an incidental harassment 
authorization (IHA) to incidentally take marine mammals during the 
specified activities. NMFS is also requesting comments on a possible 
one-year renewal that could be issued under certain circumstances and 
if all requirements are met, as described in

[[Page 13253]]

Request for Public Comments at the end of this notice. NMFS will 
consider public comments prior to making any final decision on the 
issuance of the requested MMPA authorizations and agency responses will 
be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than May 6, 
2019.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Physical comments should be sent to 
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments 
should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted online at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying 
information (e.g., name, address) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit confidential 
business information or otherwise sensitive or protected information.

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

SUPPLEMENTARY INFORMATION:

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are issued or, if the taking is limited to harassment, a notice of a 
proposed incidental take authorization may be provided to the public 
for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other means of effecting the least practicable adverse 
impact on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of such species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of such takings are set forth.
    The NDAA (Pub. L. 108-136) removed the ``small numbers'' and 
``specified geographical region'' limitations indicated above and 
amended the definition of ``harassment'' as it applies to a ``military 
readiness activity.'' The definitions of all applicable MMPA statutory 
terms cited above are included in the relevant sections below.

National Environmental Policy Act

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

Summary of Request

    On 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.
    This proposed IHA would cover one year of a larger project for 
which the Navy intends to request take authorization for subsequent 
facets of the project. The larger 5-year project after the expiration 
of this IHA (if issued) involves further dock modification and 
expansion at the Portsmouth Naval Shipyard.

Description of Proposed 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 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.

[[Page 13254]]

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 to 39 
feet at Berths 11, 12, and 13. Water depths in the lower Piscataqua 
River near the proposed project area range from 15 feet in the 
shallowest areas to 69 feet in the deepest areas. The river is 
approximately 3,300 feet 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.
BILLING CODE 3510-22-P

[[Page 13255]]

[GRAPHIC] [TIFF OMITTED] TN04AP19.006

BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    Under the proposed 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 would 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 13256]]

    To begin the project, a super flood basin would 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 feet from the existing outer seat of the 
dry dock (approximately 175 feet 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 feet 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 sf (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-foot 
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 would include 
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 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 sf (surface area) of additional fender panel would 
be required, including 3,550 sf (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 cy. 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 13257]]

 
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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    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution 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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                                                                                         ESA/MMPA  status;   Stock abundance  (CV,
             Common name                  Scientific name               Stock            strategic  (Y/N)      Nmin, most recent       PBR     Annual  M/
                                                                                                \1\          abundance survey) \2\               SI \3\
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                                         Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales)
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Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  Gulf of Maine/Bay of     -; N                79,833 (0.32, 61,415).        706        255
                                                                Fundy.
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                                                         Order Carnivora--Superfamily Pinnipedia
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Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Western North Atlantic.  -; N                75,834 (0.15, 66,884).      2,006        345
    Gray seal.......................  Halichoerus grypus.....  Western North Atlantic.  -; N                27,131 (0.19, 23,158).      5,688      1,389
    Harp seal.......................  Pagophilus               Western North Atlantic.  -; N                \4\ 7,411,000 (NA, NA)         NA    225,687
                                       groenlandicus.

[[Page 13258]]

 
    Hooded seal.....................  Cystophora cristata....  Western North Atlantic.  -; N                \5\ 593,500 (NA, NA)..         NA      1,680
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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 
below.

Harbor Porpoise

    Harbor porpoises are found commonly in coastal and offshore waters 
of both the Atlantic and Pacific Oceans. In the western North Atlantic, 
the species is found in both U.S. and Canadian waters. More 
specifically, the species can be found between West Greenland and Cape 
Hatteras, North Carolina. Of those 10 stocks that occur in U.S. waters, 
only one, the Gulf of Maine/Bay of Fundy stock, is found along the U.S. 
East Coast, and thus only individuals from this stock could be found in 
the proposed project area. The species is primarily found over the 
continental shelf in waters less than approximately 500 feet deep 
(Hayes et al. 2017). In general, the species is commonly found in bays, 
estuaries, and harbors.
    Marine mammal monitoring was conducted during the Berth 11 
Waterfront Improvements project from April 2017 through December 2017 
(Cianbro 2018a) and through June 2018 (Cianbro 2018b). Harbor porpoise 
were observed traveling quickly through the river channel and past the 
proposed project area. A total of 5 harbor porpoises were sighted 
between April 2017 and June 2018.

Harbor Seal

    Harbor seals can be found in nearshore waters along both the North 
Atlantic and North Pacific coasts, generally at latitudes above 30[deg] 
North (Burns 2009). In the western Atlantic Ocean, the harbor seal's 
range extends from the eastern Canadian Arctic to New York; however, 
they can be found as far south as the Carolinas (Waring et al. 2015). 
In New England, the species can be found in coastal waters year-round 
(Waring et al. 2015).
    Harbor seals are the most abundant pinniped in the Piscataqua 
River. They were commonly observed within the proposed project area 
between the months of April 2017 and June 2018 during the Berth 11 
Waterfront Improvements project (Cianbro 2018a, 2018b). The primary 
behaviors observed during monitoring were milling (diving) that 
occurred almost 60 percent of the time followed by swimming and 
traveling by the proposed project area at 29 percent and 12 percent, 
respectively (Cianbro 2018a). Marine mammal surveys were conducted for 
one day of each month in 2017 (NAVFAC Mid-Atlantic 2018). Harbor seals 
were observed throughout the year and did not show any seasonality in 
their presence. A high frequency of seals were documented near the 
proposed project area and frequent the river in general as the majority 
of harbor seals occur along the main coast with a large portion of them 
hauling out at the Isles of Shoals. Pupping season for harbor seals is 
May to June. No harbor seal pups were observed during the surveys, and 
known pupping sites are north of the Maine-New Hampshire border (Waring 
et al. 2016).

Gray Seal

    Gray seals are a coastal species that generally remains within the 
continental shelf region. However, they do venture into deeper water, 
as they have been known to dive up to 1,560 feet to capture prey during 
feeding.
    Gray seals within U.S. waters are considered the western North 
Atlantic stock and are expected to be part of the eastern Canadian 
population. In U.S. waters, year-round breeding of approximately 400 
animals has been documented on areas of outer Cape Cod and Muskeget 
Island in Massachusetts. In general, this species can be found year-
round in the coastal waters of the Gulf of Maine (Hayes et al. 2017).
    Gray seals were observed within the proposed project area between 
the months of April and December 2017 (Cianbro 2018a) and twice during 
the months of January through June 2018 (Cianbro 2018b). The primary 
behavior observed during surveys was milling at just over 60 percent of 
the time followed by swimming within and traveling through the proposed 
project area. Only approximately 5 percent of the time were gray seals 
observed foraging (Cianbro 2018a). Monthly marine mammal surveys also 
took place during 2017 and recorded six sightings of gray seal (NAVFAC 
Mid-Atlantic 2018). Pupping season for gray seals is December through 
February. No gray seal pups were observed during the surveys, and known 
pupping sites for gray seals (like harbor seals) are north of the 
Maine-New Hampshire border (Waring et al. 2016).

Hooded Seal

    Hooded seals are generally found in deeper waters or on drifting 
pack ice. The hooded seal is a highly migratory species, and its range 
can extend from the Canadian Arctic to Puerto Rico. In U.S. waters, the 
species has an increasing presence in the coastal waters between Maine 
and Florida (Waring et al. 2007). In the United States, they are 
considered members of the western North Atlantic stock and generally 
occur in New England waters from January through May and further south 
in the summer and fall seasons (Waring et al. 2007).
    Hooded seals have been observed in the Piscataqua River; however, 
they are not as abundant as the more commonly observed harbor seal. 
Anecdotal sighting information indicates that two hooded seals were 
observed from the Shipyard in August 2009, but no other observations 
have been recorded (NAVFAC Mid-Atlantic 2018). Hooded

[[Page 13259]]

seals were not observed during marine mammal monitoring or survey 
events that took place in 2017 and 2018 (Cianbro 2018a, b; NAVFAC Mid-
Atlantic 2018).

Harp Seal

    The harp seal is a highly migratory species, and its range can 
extend from the Canadian Arctic to New Jersey. In U.S. waters, the 
species has an increasing presence in the coastal waters between Maine 
and New Jersey (Waring et al. 2014). In the United States, they are 
considered members of the western North Atlantic stock and generally 
occur in New England waters from January through May (Waring et al. 
2014). The observed influx of harp seals and geographic distribution in 
New England to mid-Atlantic waters is based primarily on strandings and 
secondarily on fishery bycatch.
    Harp seals have been observed in the Piscataqua River; however, 
they are not as abundant as the more commonly observed harbor seal and 
were last documented in the river in 2016 (NAVFAC 2016). Harp seals 
were not observed during marine mammal monitoring or survey events that 
took place in 2017 and 2018 (Cianbro 2018a, b; NAVFAC Mid-Atlantic 
2018; Lamontagne 2018).

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 3.

           Table 3--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
          Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans       7 Hz to 35 kHz.
 (baleen whales).
Mid-frequency (MF) cetaceans       150 Hz to 160 kHz.
 (dolphins, toothed whales,
 beaked whales, bottlenose
 whales).
High-frequency (HF) cetaceans      275 Hz to 160 kHz.
 (true porpoises, Kogia, river
 dolphins, cephalorhynchid,
 Lagenorhynchus cruciger & L.
 australis).
Phocid pinnipeds (PW)              50 Hz to 86 kHz.
 (underwater) (true seals).
Otariid pinnipeds (OW)             60 Hz to 39 kHz.
 (underwater) (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.

Acoustic Effects

    Acoustic effects to marine mammals from the proposed Portsmouth 
Naval Shipyard modification and expansion construction mainly include 
behavioral disturbance and temporary masking for animals in the area. A 
few individual animals could experience mild levels of temporary and/or 
permanent hearing threshold shift.
    The Portsmouth Naval Shipyard modification and expansion 
construction project using in-water pile driving could adversely affect 
marine mammal species and stocks by exposing them to elevated noise 
levels in the vicinity of the activity area.
    Threshold Shift (noise-induced loss of hearing)--Exposure to high 
intensity sound for a sufficient duration may result in auditory 
effects such as a noise-induced threshold shift (TS)--an increase in 
the auditory threshold after exposure to noise (Finneran et al., 2005). 
Factors that influence the amount of threshold shift include the 
amplitude, duration, frequency content, temporal pattern, and energy 
distribution of noise exposure. The magnitude of hearing threshold 
shift normally decreases over time following cessation of the noise 
exposure. The amount of TS just after exposure is the initial TS. If 
the TS eventually returns to zero (i.e., the threshold returns to the 
pre-exposure

[[Page 13260]]

value), it is a temporary threshold shift (TTS) (Southall et al., 
2007). When animals exhibit reduced hearing sensitivity (i.e., sounds 
must be louder for an animal to detect them) following exposure to an 
intense sound or sound for long duration, it is referred to as a noise-
induced TS. An animal can experience TTS or permanent threshold shift 
(PTS). TTS can last from minutes or hours to days (i.e., there is 
complete recovery), can occur in specific frequency ranges (i.e., an 
animal might only have a temporary loss of hearing sensitivity between 
the frequencies of 1 and 10 kHz), and can be of varying amounts (for 
example, an animal's hearing sensitivity might be reduced initially by 
only 6 dB or reduced by 30 dB). PTS is permanent, but some recovery is 
possible. PTS can also occur in a specific frequency range and amount 
as mentioned above for TTS.
    For marine mammals, published data are limited to the captive 
bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless 
porpoise (Finneran, 2015). For pinnipeds in water, data are limited to 
measurements of TTS in harbor seals, an elephant seal, and California 
sea lions (Kastak et al., 1999, 2005; Kastelein et al., 2012b).
    Lucke et al. (2009) found a TS of a harbor porpoise after exposing 
it to airgun noise with a received sound pressure level (SPL) at 200.2 
dB (peak-to-peak) re: 1 micropascal ([mu]Pa), which corresponds to a 
sound exposure level of 164.5 dB re: 1 [mu]Pa\2\ s after integrating 
exposure. Because the airgun noise is a broadband impulse, one cannot 
directly determine the equivalent of root mean square (rms) SPL from 
the reported peak-to-peak SPLs. However, applying a conservative 
conversion factor of 16 dB for broadband signals from seismic surveys 
(McCauley, et al., 2000) to correct for the difference between peak-to-
peak levels reported in Lucke et al. (2009) and rms SPLs, the rms SPL 
for TTS would be approximately 184 dB re: 1 [mu]Pa, and the received 
levels associated with PTS (Level A harassment) would be higher. 
Therefore, based on these studies, NMFS recognizes that TTS of harbor 
porpoises is lower than other cetacean species empirically tested 
(Finneran & Schlundt, 2010; Finneran et al., 2002; Kastelein and 
Jennings, 2012).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so one can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    Masking--In addition, chronic exposure to excessive, though not 
high-intensity, noise could cause masking at particular frequencies for 
marine mammals, which utilize sound for vital biological functions 
(Clark et al., 2009). Acoustic masking is when other noises such as 
from human sources interfere with animal detection of acoustic signals 
such as communication calls, echolocation sounds, and environmental 
sounds important to marine mammals. Therefore, under certain 
circumstances, marine mammals whose acoustical sensors or environment 
are being severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction.
    Masking occurs at the frequency band that the animals utilize. 
Therefore, since noise generated from vibratory pile driving is mostly 
concentrated at low frequency ranges, it may have less effect on high 
frequency echolocation sounds by odontocetes (toothed whales). However, 
lower frequency man-made noises are more likely to affect detection of 
communication calls and other potentially important natural sounds such 
as surf and prey noise. It may also affect communication signals when 
they occur near the noise band and thus reduce the communication space 
of animals (e.g., Clark et al., 2009) and cause increased stress levels 
(e.g., Foote et al., 2004; Holt et al., 2009).
    Unlike TS, masking, which can occur over large temporal and spatial 
scales, can potentially affect the species at population, community, or 
even ecosystem levels, as well as individual levels. Masking affects 
both senders and receivers of the signals and could have long-term 
chronic effects on marine mammal species and populations. Recent 
science suggests that low frequency ambient sound levels have increased 
by as much as 20 dB (more than three times in terms of SPL) in the 
world's ocean from pre-industrial periods, and most of these increases 
are from distant shipping (Hildebrand, 2009). For the Navy's Portsmouth 
Naval Shipyard modification and expansion construction project, noises 
from pile driving contribute to the elevated ambient noise levels in 
the project area, thus increasing potential for or severity of masking. 
Baseline ambient noise levels in the vicinity of project area are high 
due to nearby industrial activities surrounding the shipyard area.
    Behavioral Disturbance--Finally, marine mammals' exposure to 
certain sounds could lead to behavioral disturbance (Richardson et al., 
1995), such as changing durations of surfacing and dives, number of 
blows per surfacing, or moving direction and/or speed; reduced/
increased vocal activities; changing/cessation of certain behavioral 
activities (such as socializing or feeding); visible startle response 
or aggressive behavior (such as tail/fluke slapping or jaw clapping); 
avoidance of areas where noise sources are located; and/or flight 
responses (e.g., pinnipeds flushing into water from haulouts or 
rookeries).
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography) and is also difficult to predict (Southall et 
al., 2007). Currently NMFS uses a received level of 160 dB re 1 [mu]Pa 
(rms) to predict the onset of behavioral disturbance from intermittent 
noises (such as impact pile driving), and 120 dB re 1 [mu]Pa (rms) for 
continuous noises (such as vibratory pile driving). For the Portsmouth 
Naval Shipyard modification and expansion construction project, both 
160- and 120-dB levels are considered for effects analysis because the 
Navy plans to conduct both impact and vibratory pile driving.
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be biologically significant if the change affects 
growth, survival, and/or reproduction, which depends on the severity, 
duration, and context of the effects.

[[Page 13261]]

Potential Effects on Marine Mammal Habitat

    Temporary and localized reduction in water quality will occur as a 
result of in-water construction activities. Most of this effect will 
occur during the installation of piles when bottom sediments are 
disturbed. Effects to turbidity and sedimentation are expected to be 
short-term, minor, and localized. Currents are strong in the area and, 
therefore, suspended sediments in the water column should dissipate and 
quickly return to background levels. Following the completion of 
sediment-disturbing activities, the turbidity levels are expected to 
return to normal ambient levels following the end of construction. 
Turbidity within the water column has the potential to reduce the level 
of oxygen in the water and irritate the gills of prey fish species in 
the proposed project area. However, turbidity plumes associated with 
the project would be temporary and localized, and fish in the proposed 
project area would be able to move away from and avoid the areas where 
plumes may occur. Therefore, it is expected that the impacts on prey 
fish species from turbidity, and therefore on marine mammals, would be 
minimal and temporary. In general, the area likely impacted by the 
project is relatively small compared to the available habitat in Great 
Bay Estuary, and there is no biologically important area for marine 
mammals that could be affected. As a result, activity at the project 
site would be inconsequential in terms of its effects on marine mammal 
foraging.
    The greatest potential impact to fish during construction would 
occur during impact pile driving when pile driving will exceed the 
established underwater noise injury thresholds for fish. However, the 
duration of impact pile driving would be limited to the final stage of 
installation (``proofing'') after the pile has been driven as close as 
practicable to the design depth with a vibratory driver. Vibratory pile 
driving would possibly elicit behavioral reactions from fish such as 
temporary avoidance of the area but is unlikely to cause injuries to 
fish or have persistent effects on local fish populations. In addition, 
it should be noted that the area in question is low-quality habitat 
since it is already highly developed and experiences a high level of 
anthropogenic noise from normal Shipyard operations and other vessel 
traffic. In general, impacts on marine mammal prey species are expected 
to be minor and temporary.
    All marine mammal species using habitat near the proposed project 
area are primarily transiting the area; no known foraging or haulout 
areas are located within 1.5 miles of the proposed project area. The 
most likely impacts on marine mammal habitat for the project are from 
underwater noise, turbidity, and potential effects on the food supply. 
However, it is not expected that any of these impacts would be 
significant.
    Construction may have temporary impacts on benthic invertebrate 
species, another marine mammal prey source. Direct benthic habitat loss 
would result with the permanent loss of approximately 3.5 acres of 
benthic habitat from construction of the super flood basin. However, 
the areas to be permanently removed are beneath and adjacent to the 
existing berths along the Shipyard's industrial waterfront and are 
regularly disturbed as part of the construction dredging to maintain 
safe navigational depths at the berths. Further, vessel activity at the 
berths creates minor disturbances of benthic habitats (e.g., vessel 
propeller wakes) during waterfront operations. Therefore, impacts of 
the project are not likely to have adverse effects on marine mammal 
foraging habitat in the proposed project area.

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, 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.

[[Page 13262]]

    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 (Lpk) 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 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.

[[Page 13263]]



                                                 Table 5--Summary of In-Water Pile Driving Source Levels
                                                                  [At 10 m from source]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       SEL, dB  re 1   SPLrms, dB   SPLpk, dB     Measured
                 Method                      Pile type/size (inch)     [micro]Pa\2\-      re 1         re 1       distance              Origin
                                                                             s         [micro]Pa    [micro]Pa       (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Vibratory pile driving..................  Steel, 36-inch.............           175           175           NA           10  Caltrans.
Impact pile driving.....................  Steel, 36-inch.............           183           198          209           10  Navy New London.
Vibratory pile driving..................  Steel H, 14-inch...........           158           158           NA           10  Caltrans.
Impact pile driving.....................  Steel H, 14-inch...........           162           177          194           10  Navy Portsmouth SSV.
Vibratory pile driving..................  Steel sheet, 24-inch & 18-            163           163           NA           10  NAVFAC Atlantic Fleet.
                                           inch.
Impact pile driving.....................  Steel sheet, 24-inch & 18-            180           190          205           10  Caltrans.
                                           inch.
Down-the-hole piling....................  Steel pile casing 96-inch..         166.2         166.2           NA           10  Kodiak, AK.
Vibratory pile driving..................  Steel, 16-inch.............           162           162           NA           10  Naval Base Kitsap Bangor,
                                                                                                                              WA.
Impact pile driving.....................  Steel, 16-inch.............           158           163          182           10  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] TN04AP19.007

where R is the harassment distance.
    However, the maximum distance from the source is capped at 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).

                                                    Table 6--Distances and Areas of Harassment Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                            Level A harassment                     Level B harassment
                                                                 Duration  -----------------------------------------------------------------------------
                                                                 (sec) or          HF cetacean                 Phocid
               Pile type, size & driving method                   number   ----------------------------------------------------                  Area
                                                               strikes per                   Area                      Area      Dist. (m)     (km\2\)
                                                                   pile      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        1,763        0.854          792        0.854        1,000        0.854
Vibratory removal 14-inch H-pile (8 pile/day)................          300          4.9        0.001            2        0.000        3,414        0.854
Vibratory drive 14-inch H-pile (1 pile/day)..................          300          1.2        0.000          0.5        0.000        3,414        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       10,000        0.854
Vibratory drive 36-inch steel pipe pile (1 pile/day).........          300         16.5        0.001          6.8        0.000       10,000        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        6,310        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, harbor seal, 
and gray seal are derived based on marine

[[Page 13264]]

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.

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

    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\. 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\. 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\.
    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 known density information (i.e., harbor 
porpoise, harbor seal, and gray seal), in general, estimated Level A 
harassment take numbers are calculated using the following equation:
[GRAPHIC] [TIFF OMITTED] TN04AP19.008

    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.
    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.....................................             287             400             687            0.91
Gray seal.......................................              25              35              60            0.21
Hooded seal.....................................               0               5               5            0.00
Harp seal.......................................               0               5               5            0.00
----------------------------------------------------------------------------------------------------------------

Proposed Mitigation

    In order to issue an IHA under Section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses. 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:

[[Page 13265]]

    (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 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 
preliminarily 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.

Proposed Monitoring and Reporting

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

[[Page 13266]]

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.

Proposed 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 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

[[Page 13267]]

    [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).
    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 preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
     No mortality is anticipated or authorized;
     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 preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized

[[Page 13268]]

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 one 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 preliminarily finds that small 
numbers of marine mammals will be taken relative to the population size 
of the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

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

Endangered Species Act (ESA)

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

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to 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 mentioned 
mitigation, monitoring, and reporting requirements are incorporated. A 
draft of the proposed IHA can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed 
issuance of an IHA to the Navy incidence to conduct Portsmouth Naval 
Shipyard Dry Dock 1 Modification and Expansion in Kittery, Maine, 
between October 1, 2019, and September 30, 2010. We also request 
comment on the potential for renewal of this proposed IHA as described 
in the paragraph below. Please include with your comments any 
supporting data or literature citations to help inform our final 
decision on the request for MMPA authorization.
    On a case-by-case basis, NMFS may issue a second one-year IHA 
without additional notice when (1) another year of identical or nearly 
identical activities as described in the Specified Activities section 
is planned or (2) the activities would not be completed by the time the 
IHA expires and a second IHA would allow for completion of the 
activities beyond that described in the Dates and Duration section, 
provided all of the following conditions are met:
     A request for renewal is received no later than 60 days 
prior to expiration of the current IHA;
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted beyond the 
initial dates either are identical to the previously analyzed 
activities or include changes so minor (e.g., reduction in pile size) 
that the changes do not affect the previous analyses, take estimates, 
or mitigation and monitoring requirements; and
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized; and
     Upon review of the request for renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures remain the same and appropriate, 
and the original findings remain valid.

    Dated: March 28, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2019-06537 Filed 4-3-19; 8:45 am]
BILLING CODE 3510-22-P