Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to U.S. Navy Construction of the Pier 3 Replacement Project at Naval Station Norfolk, 14560-14590 [2023-04613]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 88, Number 46 (Thursday, March 9, 2023)]
[Proposed Rules]
[Pages 14560-14590]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-04613]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 230302-0061]
RIN 0648-BL81


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to U.S. Navy Construction of the Pier 
3 Replacement Project at Naval Station Norfolk

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

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to the replacement of 
Pier 3 at Naval Station (NAVSTA) Norfolk in Norfolk, Virginia over the 
course of five years (2023-2028). Pursuant to the Marine Mammal 
Protection Act (MMPA), NMFS is proposing regulations to govern that 
take, and requests comments on the proposed regulations. Agency 
responses will be included in the notice of the final decision.

DATES: Comments and information must be received no later than April 
10, 2023.

ADDRESSES: A copy of the Navy's application and any supporting 
documents, as well as a list of the references cited in this document, 
may be obtained online at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-us-navy-replacement-pier-3-naval-station-norfolk-norfolk. In case of problems accessing these documents, please 
call the contact listed below (see FOR FURTHER INFORMATION CONTACT).
    Submit all electronic public comments via the Federal e-Rulemaking 
Portal. Go to www.regulations.gov and enter NOAA-NMFS-2022-0110 in the 
Search box. Click on the ``Comment'' icon, complete the required 
fields, and enter or attach your comments.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. All comments received are a part of the 
public records and will generally be posted for public viewing on 
www.regulations.gov without change. All personal identifying 
information (e.g., name, address), confidential business information, 
or otherwise sensitive information submitted voluntarily by the sender 
will be publicly accessible. NMFS will accept anonymous comments (enter 
``N/A'' in the required fields if you wish to remain anonymous). 
Attachments to electronic comments will be accepted in Microsoft Word, 
Excel, or Adobe PDF file formats only.

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

SUPPLEMENTARY INFORMATION: 

Purpose and Need for Regulatory Action

    This proposed rule would establish a framework under the authority 
of the MMPA (16 U.S.C. 1361 et seq.) to allow for the authorization of 
take of marine mammals incidental to the Navy's construction activities 
including pile driving and drilling activities at Naval Station 
(NAVSTA) Norfolk.
    We received an application from the Navy requesting five-year 
regulations and authorization to take multiple species of marine 
mammals. Take would occur by Level B and Level A harassment, incidental 
to impact and vibratory pile driving and drilling. Please see 
Background below for definitions of harassment.

Legal Authority for the Proposed Action

    Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1371(a)(5)(A)) directs 
the Secretary of Commerce to allow, upon request, the incidental, but 
not intentional, taking of small numbers of marine mammals by U.S. 
citizens who engage in a specified activity (other than commercial 
fishing) within a specified geographical region for up to five years 
if, after notice and public comment, the agency makes certain findings 
and issues regulations that set forth permissible methods of taking 
pursuant to that activity and other means of effecting the ``least 
practicable adverse impact'' on the affected species or stocks and 
their habitat (see the discussion below in the Proposed Mitigation 
section), as well as monitoring and reporting requirements. Section 
101(a)(5)(A) of the MMPA and the implementing regulations at 50 CFR 
part 216, subpart I provide the legal basis for issuing this proposed 
rule containing 5-year regulations, and for any subsequent letters of 
authorization (LOAs). As directed by this legal authority, this 
proposed rule contains mitigation, monitoring, and reporting 
requirements.

Summary of Major Provisions Within the Proposed Rule

    Following is a summary of the major provisions of this proposed 
rule regarding Navy construction activities. These measures include:
     Required monitoring of the construction areas to detect 
the presence of marine mammals before beginning construction 
activities;
     Shutdown of construction activities under certain 
circumstances to avoid injury of marine mammals;
     Soft start for impact pile driving to allow marine mammals 
the opportunity to leave the area prior to beginning impact pile 
driving at full power.

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 proposed or, if the taking is limited to harassment, a notice of a 
proposed IHA is 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

[[Page 14561]]

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 
the 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 the takings are set forth. 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 IHA) 
with respect to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs 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 review under NEPA.
    We will review all comments submitted in response to this document 
prior to concluding our NEPA process or making a final decision on the 
IHA request.

Summary of Request

    On April 8, 2022, NMFS received a request from the Navy for 
authorization to take marine mammals incidental to construction 
activities related to the replacement of Pier 3 at Naval Station 
Norfolk in Norfolk, Virginia. Following NMFS' review of the 
application, the Navy provided responses to questions on June 3, 2022 
and August 29, 2022. A revised version of the application was submitted 
on September 22, 2022. The application was deemed adequate and complete 
on September 26, 2022 and published for public review and comment on 
October 7, 2022 (87 FR 60998). We did not receive substantive comments 
on the NOR.
    The Navy requests authorization to take a small number of five 
species of marine mammals by Level B harassment and, for harbor 
porpoise and harbor seal, Level A harassment. Neither the Navy nor NMFS 
expect serious injury or mortality to result from this activity. The 
proposed regulations would be valid for five years (2023-2028).

Description of Proposed Activity

Overview

    The Navy is currently conducting, and proposes to continue, the 
replacement of Pier 3 at NAVSTA Norfolk, in Norfolk, VA. This proposed 
rule follows an Incidental Harassment Authorization (IHA) issued to the 
Navy on March 15, 2022, effective from April 1, 2022 through March 31, 
2023 (87 FR 15945; March 21, 2022), which covered the first year of 
project activities, and covers the remaining activities for the pier 
replacement. During this period demolition and construction activities 
will occur at existing Pier 3, new Pier 3, CEP-176 wharf, CEP-102 
relieving platform, and on a fender system of CEP-175 bulkhead (See 
Figure 1). The proposed project includes both vibratory pile driving 
and removal, impact pile driving, and pre-drilling (hereafter, referred 
to as ``drilling''). Sounds resulting from pile driving, drilling and 
removal may result in the incidental take of marine mammals by Level A 
and Level B harassment in the form of auditory injury or behavioral 
harassment.

Dates and Duration

    The proposed regulations would be valid for a period of five years 
(2023-2028) The specified activities may occur at any time during the 
five-year period of validity of the proposed regulations. The Navy 
expects pile driving and drilling for the entire project to occur on 
approximately 513 non-consecutive days over a four year duration, with 
the greatest amount of work occurring during Year 4 (approximately 204 
days). However, in the event of unforeseen delays, the project may 
occur over the full 5-year duration of this proposed rule. The Navy 
plans to conduct all work during daylight hours.

Specific Geographic Region

    Pier 3 at NAVSTA Norfolk is located at the confluence of the 
Elizabeth River, James River, Nansemond River, LaFeyette River, 
Willoughby Bay, and Chesapeake Bay (Figure 2).
    Anthropogenic sound is a significant contributor to the ambient 
acoustic environment surrounding NAVSTA Norfolk, as it is located in 
close proximity to shipping channels as well as several Port of 
Virginia facilities with frequent vessel traffic that altogether have 
an annual average of 1,788 vessel calls (Port of Virginia, 2021). Other 
sources of human-generated underwater sound not specific to naval 
installations include sounds from echosounders on commercial and 
recreational vessels, industrial ship noise, and noise from 
recreational boat engines. Additionally, on average, maintenance 
dredging of the navigation channel occurs every 2 years (USACE and Port 
of Virginia, 2018).
BILLING CODE 3510-22-P

[[Page 14562]]

[GRAPHIC] [TIFF OMITTED] TP09MR23.010

Figure 1: Site Location Map for NAVSTA Norfolk in Norfolk, Virginia

[[Page 14563]]

[GRAPHIC] [TIFF OMITTED] TP09MR23.011

Figure 2: Project Site Map at NAVSTA Norfolk in Norfolk, Virginia
BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The proposed project involves the replacement of Pier 3 at NAVSTA 
waterfront. The existing Pier 3 would be completely demolished and a 
new Pier 3 would be constructed immediately north of the existing 
location (Figure 2). The project scope for the replacement of Pier 3 
under this proposed rule would also include construction of new CEP-176 
wharf, construction of new CEP-102 relieving platform, and construction 
of a portion of fender system at CEP-175. The project includes 6 
phases, the first of which has begun under the previously issued IHA 
(87 FR 15945; March 21, 2022). A preliminary work schedule and activity 
details for the work under this proposed rule are provided in Table 1. 
In-water construction activities, including pile driving, pile removal, 
and drilling are described in detail below:
    Pile Removal--Piles are anticipated to be removed with a vibratory 
hammer, however, direct pull or clamshell removal may be used depending 
on site conditions. All three pile removal methods are described below. 
Take is not expected to occur for clamshell and direct pull removal, 
therefore they will not be described past what is provided below nor 
included in our analysis:

[[Page 14564]]

     Vibratory Extraction--This method uses a barge-mounted 
crane with a vibratory driver to remove all pile types. The vibratory 
driver is a large mechanical device (5 to 16 tons) suspended from a 
crane by a cable and positioned on top of a pile. The pile is then 
loosened from the sediments by activating the driver and slowly lifting 
up on the driver with the aid of the crane. Once the pile is released 
from the sediments, the crane continues to raise the driver and pull 
the pile from the sediment. The driver is typically shut off once the 
pile is loosened from the sediments. The pile is then pulled from the 
water and placed on a barge. Vibratory extraction usually takes between 
less than 1 minute (for timber piles) to 30 minutes per pile depending 
on the pile size, type, and substrate conditions;
     Clamshell--In cases where use of a vibratory driver is not 
possible (e.g., when the pile may break apart from clamp force and 
vibration), a clamshell apparatus may be lowered from the crane in 
order to remove pile stubs. The use and size of the clamshell bucket 
would be minimized to reduce the potential for generating turbidity 
during removal; and
     Direct Pull--Piles may be removed by wrapping the piles 
with a cable or chain and pulling them directly from the sediment with 
a crane. In some cases, depending on access and location, piles may be 
cut at or below the mudline.
    Pile Installation--Pile installation/removal would occur using 
land-based or barge-mounted cranes, as appropriate. Concrete piles 
would be installed using an impact hammer. Steel piles and polymeric 
piles can be installed using an impact hammer or vibratory hammer. 
Hammers can be steam, air, or diesel drop, single-acting, double-
acting, differential-acting, or hydraulic type. Additionally, pre-
drilling may occur for installation of concrete piles and at locations 
where there may be a higher likelihood of obstructions or where soil 
layers are harder to penetrate. Drilling is not permitted for 
installation of steel piles on this project or for concrete piles at 
Pier 3 because hard soil layers are not expected at these locations.
    Table 1 provides the estimated construction schedule and production 
rates for the proposed construction activities considered for this 
proposed rulemaking beginning with Year 2. As indicated above, Year 1 
of the Pier 3 replacement project was authorized under the 2022 IHA, 
effective from April 1, 2022-March 31, 2023. Therefore, Year 2 of the 
project aligns with year 1 of the proposed rule. Some project elements 
will use only one method of pile installation (e.g., impact hammer or 
vibratory hammer or impact hammer and drilling), but all methods have 
been analyzed. The method of installation will be determined by the 
construction crew once demolition and installation has begun.

                       Table 1--Preliminary Construction Schedule for In-Water Activities
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                                  Total                                       Daily rate
  Year ***       Activity       number of      Activity           Method        (piles/   Total days  Total days
                                  piles        component                         day)                  per year
----------------------------------------------------------------------------------------------------------------
Year 2.....  CEP-176 Bulkhead         103  42 inch Steel     Install: Impact           4          26         185
                                            Pipe Bearing      or Vibratory.
                                            Piles.
Year 2.....  CEP-176 Bulkhead         221  28 inch sheet     Install: Impact          14          16
                                            piles.            or Vibratory.
Year 2.....  CEP-176 Bulkhead           9  13 inch           Install: Impact           5           2
                                            polymeric         or Vibratory *.
                                            fender piles.
Year 2.....  CEP-102 Platform          11  24 inch square    Install: Impact           2           6
              phase 2.                      precast           *.
                                            concrete
                                            bearing piles.
Year 2.....  Pier 3..........         280  24 inch square    Install: Impact           4          70
                                            precast
                                            concrete.
Year 2.....  CEP-102 Platform           6  18 inch square    Install: Impact           4           2
              phase 2.                      precast
                                            concrete fender
                                            piles.
Year 2.....  Pier 3..........         250  24 inch square    Install: Impact           4          63
                                            precast
                                            concrete
                                            bearing piles.
Year 3.....  Pier 3..........         409  24 inch square    Install: Impact           6          69          92
                                            precast           *.
                                            concrete fender
                                            files.
Year 3.....  Pier 3..........          18  18 inch steel     Install: Impact           6           3
                                            pipe fender
                                            piles.
Year 3.....  CEP-102 Platform          26  42 inch steel     Install: Impact           2          13
              South Portion.                pipe bearing      or Vibratory.
                                            piles.
Year 3.....  CEP-102 Platform          53  28 inch steel     Install: Impact          14           4
              South Portion.                sheet piles.      or Vibratory.
Year 3.....  CEP-102 Platform          26  18 inch square    Extract:                  9           3
              South Portion.                precast           Vibratory.
                                            concrete fender
                                            piles **.
Year 4.....  CEP-102 Platform          40  24 inch square    Install: Impact           2          20         204
              South Portion.                precast           *.
                                            concrete
                                            bearing piles.
Year 4.....  Existing Pier 3.         624  14 inch timber    Extract:                 25          25
                                            fender piles **.  Vibratory.
Year 4.....  CEP-102 Platform          25  18 inch square    Install: Impact           4           7
              South Portion.                precast           *.
                                            concrete fender
                                            piles.
Year 4.....  CEP-102 Platform          50  42 inch steel     Install: Impact           2          25
              Center Portion.               pipe bearing      or Vibratory.
                                            piles.
Year 4.....  Existing Pier 3.          72  24 inch square    Extract:                 12           6
                                            precast           Vibratory.
                                            concrete fender
                                            piles **.
Year 4.....  CEP-102 Platform         102  28 inch steel     Install: Impact          14           8
              Center Portion.               sheet piles.      or Vibratory.
Year 4.....  CEP-102 Platform          36  18 inch square    Extract:                  9           4
              Center Portion.               precast           Vibratory.
                                            concrete fender
                                            piles **.
Year 4.....  Existing Pier 3.         873  16 inch and 18    Extract:                 10          88
                                            inch square       Vibratory.
                                            precast
                                            concrete
                                            bearing piles
                                            **.
Year 4.....  CEP-102 Platform          41  24 inch square    Install: Impact           2          21
              Center Portion.               precast           *.
                                            concrete
                                            bearing piles.
Year 5.....  Existing Pier 3.          30  16 and 18 inch    Extract:                 10           3          32
                                            square precast    Vibratory.
                                            bearing piles
                                            **.
Year 5.....  CEP-102 Platform          32  24 inch square    Install: Impact           2          16
              Center Portion.               precast bearing   *.
                                            piles.
Year 5.....  CEP-102 Platform          50  18 inch square    Install: Impact           4          13
              Center Portion.               precast           *.
                                            concrete fender
                                            piles.
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[[Page 14565]]

 
    Total Piles Installed....       1,726                                                             Total: 513
            ------------------                                                           -----------------------
    Total Piles Removed......       1,661
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Note: Estimated construction schedule. Delays may occur due to equipment failure or weather.
* Pre-drilling is permitted to assist with pile installation.
** Denotes Piles Removed.
*** Year 2 refers to the second year of the Pier 3 replacement project, however it is considered as Year 1 under
  the 2023 Rule proposed for authorization.

    Concurrent Activities--In order to maintain project schedules, it 
is likely that multiple pieces of equipment would operate at the same 
time within the project area. Table 2 provides a summary of the 
possible equipment combinations by structure and construction year 
where a maximum of four in-water activities may be occurring 
simultaneously. As mentioned above, the method of installation, and 
whether concurrent pile driving scenarios will be implemented, will be 
determined by the construction crew once the project has begun. 
Therefore, the total take estimate reflects the worst case scenario for 
the proposed project.

                         Table 2--Summary of Possible Concurrent Pile Driving Scenarios
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                                                                                 Total
            Year                     Structure              Pile types         equipment   Equipment  (quantity)
                                                                               quantity
----------------------------------------------------------------------------------------------------------------
Year 3......................  Pier 3................  Driving of precast               2  Rotary Drill (2).
                                                       bearing piles.                  2  Impact Hammer (1),
                                                                                           Rotary Drill (1).
                                                                                       2  Impact Hammer (2).
                              CEP-102...............  Driving 42-inch steel            2  Vibratory Hammer (2).
                                                       pipe and 28-inch                2  Impact Hammer (2).
                                                       steel sheet.
                                                                                       2  Vibratory Hammer (1),
                                                                                           Impact Hammer (1).
Year 4......................  Existing Pier 3 and     Extraction of 14-inch            4  Vibratory Hammer (3),
                               CEP-102.                timber piles from               4   Rotary Drill (1).
                                                       Pier 3 and Driving of  ..........  Vibratory Hammer (2),
                                                       42-inch steel pipe,             4   Impact Hammer (2),
                                                       sheet piles, and                    Rotary Drill (1).
                                                       precast concrete                   Vibratory (1), Impact
                                                       piles.                              Hammer (3).
Year 4-Year 5...............  Existing Pier 3 and     Extraction of 16- to             2  Vibratory Hammer (1),
                               CEP-102.                18-inch concrete                2   Rotary Drill (1).
                                                       piles from Pier 3 and              Vibratory Hammer (1),
                                                       Driving of 24-inch                  Impact Hammer (1).
                                                       precast concrete
                                                       bearing piles.
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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. NMFS 
fully considered all of this information, and we refer the reader to 
these descriptions, incorporated here by reference, instead of 
reprinting the information. Additional information regarding population 
trends and threats may be found in NMFS' Stock Assessment Reports 
(SARs; 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' website (https://www.fisheries.noaa.gov/find-species).
    Table 3 lists all species or stocks for which take is expected and 
proposed to be authorized for this activity, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and Endangered Species Act (ESA) and potential biological 
removal (PBR), where known. 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' 
SARs). While no serious injury or mortality is expected to occur, PBR 
and annual serious injury and mortality from anthropogenic sources are 
included here as gross indicators of the status of the species or 
stocks 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' 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 stocks managed under the MMPA in this region 
are assessed in NMFS' U.S. draft 2022 SARs. All values presented in 
Table 2 are the most recent available at the time of publication and 
are available online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

[[Page 14566]]



                                              Table 3--Species Likely Impacted by the Specified Activities
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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\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals):
    Humpback whale..................  Megaptera novaeangliae.  Gulf of Maine..........  -,-, Y              1,396 (0, 1,380, 2016)         22      12.15
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Bottlenose Dolphin..............  Tursiops truncatus.....  Western North Atlantic   -,-, Y              6,639 (0.41, 4,759,            48  12.2-21.5
                                                                (WNA) Coastal,                               2016).
                                                                Northern Migratory.
                                                               WNA Coastal, Southern    -, -, Y             3,751 (0.6, 2,353,             24     0-18.3
                                                                Migratory.                                   2016).
                                                               Northern North Carolina  -, -, Y             823 (0.06, 782, 2017).        7.8     7.2-30
                                                                Estuarine.
Family Phocoenidae (porpoises):
    Harbor Porpoise.................  Phocoena phocoena......  Gulf of Maine/Bay of     -, -, N             95,543 (0.31, 74,034,         851        164
                                                                Fundy.                                       2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Western North Atlantic.  -, -, N             61,336 (0.08, 57,637,       1,729        339
                                                                                                             2018).
    Gray seal \4\...................  Halichoerus grypus.....  Western North Atlantic.  -, -, N             27,300 (0.22, 22,785,       1,458       4453
                                                                                                             2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\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. 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\ This stock abundance estimate is only for the U.S. portion of this stock. The actual stock abundance, including the Canadian portion of the
  population, is estimated to be approximately 424,300 animals. The PBR value listed here is only for the U.S. portion of the stock, while M/SI reflects
  both the Canadian and U.S. portions.

    As indicated above, all five species (with seven managed stocks) in 
Table 3 temporally and spatially co-occur with the activity to the 
degree that take is reasonably likely to occur. While North Atlantic 
right whales (Eubalaena glacialis), minke whales (Balaenoptera 
acutorostrata acutorostata), and fin whales (Balaenoptera physalus) 
have been documented in the area, the temporal and/or spatial 
occurrence of these whales is far outside the proposed area for this 
project and take is not expected to occur. Therefore, they are not 
discussed further beyond the explanation provided below.
    Based on sighting data and passive acoustic studies, the North 
Atlantic right whale could occur off the coast of Virginia year-round 
(Department of Navy (DoN) 2009; Salisbury et al., 2016). They have also 
been reported seasonally off Virginia during migrations in the spring, 
fall, and winter (Cotter 2019). Right whales are known to frequent the 
coastal waters of the mouth of the Chesapeake Bay (Knowlton et al., 
2002) and the area is a seasonal management area (November 1-April 30) 
mandating reduced ship speeds out to approximately 20 nautical miles 
(37 kilometers [km]); however, the project area is further inside the 
Bay and away from this area.
    North Atlantic right whales have stranded in Virginia, one each in 
2001, 2002, 2004, 2005; three during winter (February and March) and 
one in the summer (September) (Costidis et al., 2017, 2019). In January 
2018, a dead, entangled North Atlantic right whale was observed 
floating over 60 miles (96.6 km) offshore of Virginia Beach (Costidis 
et al., 2019). All North Atlantic right whale strandings in Virginia 
waters have occurred on ocean-facing beaches along Virginia Beach and 
the barrier islands seaward of the lower Delmarva Peninsula (Costidis 
et al., 2017). Right whales are not expected to occur in the project 
area, and NMFS is not proposing to authorize take of this species.
    Fin whales have been sighted off Virginia (Cotter 2019), and in the 
Chesapeake Bay (Aschettino et al., 2018); however, they are not likely 
to occur in the project area. Sightings have been documented around the 
Chesapeake Bay Bridge Tunnel (CBBT) during winter months (Aschettino et 
al., 2018).
    Eleven fin whale strandings have occurred off Virginia from 1988 to 
2016, mostly during the winter months of February and March, followed 
by a few in the spring and summer months (Costidis et al., 2017). Six 
of the strandings occurred in the Chesapeake Bay (three on the eastern 
shore; three on the western shore) with the remaining five occurring on 
the Atlantic coast (Costidis et al.,2017). Documented strandings near 
the project area have occurred: February 2012, a dead fin whale washed 
ashore on Oceanview Beach in Norfolk (Swingle et al., 2013); December 
2017, a live fin whale stranded on a shoal in Newport News and died at 
the site (Swingle et al., 2018); February 2014, a dead fin whale 
stranded on a sand bar in Pocomoke Sound near Great Fox Island, 
Accomack (Swingle et al., 2015); and, March 2007, a dead fin whale near 
Craney Island, in the Elizabeth River, in Norfolk (Barco 2013). Only 
stranded fin whales have been documented in the project area; no free 
swimming fin whales have been observed. Fin whales are not expected to 
occur in the project area, and NMFS is not proposing to authorize take 
of this species.

[[Page 14567]]

    Minke whales have been sighted off Virginia (CeTAP 1981, 1982; 
Hyrenbach et al., 2012; Barco 2013; Mallette et al., 2016a, b; McLellan 
2017; Engelhaupt et al., 2017, 2018; Cotter 2019), near the CBBT 
(Aschettino et al., 2018), but sightings in the project area are from 
strandings (Jensen and Silber 2004; Barco 2013; DoN 2009). In August 
1994, a ship strike incident involved a minke whale in Hampton Roads 
(Jensen and Silber 2004; Barco 2013). It was reported that the animal 
was struck offshore and was carried inshore on the bow of a ship (DoN 
2009). Twelve strandings of minke whales have occurred in Virginia 
waters from 1988 to 2016 (Costidis et al., 2017). There have been six 
minke whale stranding from 2017 through 2020 in Virginia waters. Minke 
whales are not expected to occur in the project area, and NMFS is not 
proposing to authorize take of this species.
Humpback Whale
    Humpback whales are found worldwide in all oceans. In winter, 
humpback whales from waters off New England, Canada, Greenland, 
Iceland, and Norway, migrate to mate and calve primarily in the West 
Indies, where spatial and genetic mixing among these groups occurs. 
NMFS defines a humpback whale stock on the basis of feeding location, 
i.e., Gulf of Maine. However, our reference to humpback whales in this 
document refers to any individual of the species that are found in the 
species geographic region. These individuals may be from the same 
breeding population (e.g., West Indies breeding population of humpback 
whales) but visit different feeding areas.
    Based on photo-identification studies, only 39 percent of 
individual humpback whales observed along the mid- and south Atlantic 
U.S. coast are from the Gulf of Maine stock (Barco et al., 2002). 
Therefore, the SAR abundance estimate is an underrepresentation of the 
relevant population, i.e., the West Indies breeding population.
    Prior to 2016, humpback whales were listed under the ESA as an 
endangered species worldwide. Following a 2015 global status review 
(Bettridge et al., 2015), NMFS established 14 Distinct Population 
Segments (DPSs) with different listing statuses (81 FR 62259; September 
8, 2016) pursuant to the ESA. Humpback whales in the project area are 
expected to be from the West Indies DPS, which consists of the whales 
whose breeding range includes the Atlantic margin of the Antilles from 
Cuba to northern Venezuela, and whose feeding range primarily includes 
the Gulf of Maine, eastern Canada, and western Greenland. This DPS is 
not ESA listed. Bettridge et al., (2003) estimated the size of the West 
Indies DPS at 12,312 (95% CI 8,688-15,954) whales in 2004-05, which is 
consistent with previous population estimates of approximately 10,000-
11,000 whales (Stevick et al., 2003; Smith et al., 1999) and the 
increasing trend for the West Indies DPS (Bettridge et al., 2015).
    Although humpback whales are migratory between feeding areas and 
calving areas, individual variability in the timing of migrations may 
result in the presence of individuals in high-latitude areas throughout 
the year (Straley, 1990). Records of humpback whales off the U.S. mid-
Atlantic coast (New Jersey to North Carolina) from January through 
March suggest these waters may represent a supplemental winter feeding 
ground used by juvenile and mature humpback whales of U.S. and Canadian 
North Atlantic stocks (LaBrecque et al., 2015).
    Humpback whales are most likely to occur near the mouth of the 
Chesapeake Bay and coastal waters of Virginia Beach between January and 
March; however, they could be found in the area year-round, based on 
shipboard sighting and stranding data (Barco and Swingle, 2014; 
Aschettino et al., 2015; 2016; 2017; 2018). Photo-identification data 
support the repeated use of the mid-Atlantic region by individual 
humpback whales. Results of the vessel surveys show site fidelity in 
the survey area for some individuals and a high level of occurrence 
within shipping channels--an important high-use area by both the Navy 
and commercial traffic (Aschettino et al., 2015; 2016; 2017; 2018). 
Nearshore surveys conducted in early 2015 reported 61 individual 
humpback whale sightings, and 135 individual humpback whale sightings 
in late 2015 through May 2016 (Aschettino et al., 2016). Subsequent 
surveys confirmed the occurrence of humpback whales in the nearshore 
survey area: 248 individuals were detected in 2016-2017 surveys 
(Aschettino et al., 2017), 32 individuals were detected in 2017-2018 
surveys (Aschettino et al., 2018), and 80 individuals were detected in 
2019 surveys (Aschettino et al., 2019). Sightings in the Hampton Roads 
area in the vicinity of NAVSTA Norfolk were reported in nearshore 
surveys and through tracking of satellite-tagged whales in 2016, 2017 
and 2019. The numbers of whales detected, most of which were juveniles, 
reflect the varying level of survey effort and changes in survey 
objectives from year to year, and do not indicate abundance trends over 
time. Most recently, the Hampton Roads Bridge-Tunnel Expansion Project 
(HRBT), which spanned from September 2020 through July 10, 2021 did not 
observe any humpback whales near the project site between Norfolk and 
Hampton, VA over 197 days of observations (Hampton Roads Connector 
Partners (HRCP), Unpublished).
Bottlenose Dolphin
    Along the U.S. East Coast and northern Gulf of Mexico, the 
bottlenose dolphin stock structure is well studied. There are currently 
53 management stocks identified by NMFS in the western North Atlantic 
and Gulf of Mexico, including oceanic, coastal, and estuarine stocks 
(Hayes et al., 2017; Waring et al., 2015, 2016).
    A recent study proposes that bottlenose dolphins inhabiting 
nearshore coastal and estuarine waters between New York and Florida are 
likely a separate species from their offshore counterparts (Costa et 
al., 2022). The offshore form is larger in total length and skull 
length, and has wider nasal bones than the coastal form. Both inhabit 
waters in the western North Atlantic Ocean and Gulf of Mexico (Curry 
and Smith, 1997; Hersh and Duffield, 1990; Mead and Potter, 1995) along 
the U.S. Atlantic coast. The coastal species of bottlenose dolphin is 
continuously distributed along the Atlantic coast south of Long Island, 
New York, around the Florida peninsula, and along the Gulf of Mexico 
coast. This type typically occurs in waters less than 25 meters deep 
(Waring et al., 2015). The range of the offshore bottlenose dolphin 
includes waters beyond the continental slope (Kenney, 1990), and 
offshore bottlenose dolphins may move between the Gulf of Mexico and 
the Atlantic (Wells et al., 1999).
    Two coastal stocks are likely to be present in the project area: 
the Western North Atlantic Northern Migratory Coastal stock and the 
Western North Atlantic Southern Migratory Coastal stock. Additionally, 
the Northern North Carolina Estuarine System stock may occur in the 
project area.
    Bottlenose dolphins are the most abundant marine mammal along the 
Virginia coast and within the Chesapeake Bay, typically traveling in 
groups of 2 to 15 individuals, but occasionally in groups of over 100 
individuals (Engelhaupt et al., 2014; 2015; 2016). Bottlenose dolphins 
of the Western North Atlantic Northern Migratory Coastal stock winter 
along the coast of North Carolina and migrate as far north as Long 
Island, New York, in the summer. They are rarely found north of North 
Carolina in the winter (NMFS, 2018). The Western North Atlantic 
Southern Migratory Coastal

[[Page 14568]]

stock occurs in waters of southern North Carolina from October to 
December, moving south during winter months and north to North Carolina 
during spring months. During July and August, the Western North 
Atlantic Southern Migratory Coastal stock is presumed to occupy coastal 
waters north of Cape Lookout, North Carolina, to the eastern shore of 
Virginia (NMFS, 2018). It is possible that these animals also occur 
inside the Chesapeake Bay and in nearshore coastal waters. The North 
Carolina Estuarine System stock dolphins may also occur in the 
Chesapeake Bay during July and August (NMFS, 2018a).
    Vessel surveys conducted along coastal and offshore transects from 
NAVSTA Norfolk to Virginia Beach in most months from August 2012 to 
August 2015 reported bottlenose dolphins throughout the survey area, 
including the vicinity of NAVSTA Norfolk (Engelhaupt et al., 2014; 
2015; 2016). The final results from this project confirmed earlier 
findings that bottlenose dolphins are common in the study area, with 
highest densities in the coastal waters in summer and fall months. 
However, bottlenose dolphins do not completely leave this area during 
colder months, with approximately 200-300 individuals still present in 
winter and spring months, which is commonly referred to as the 
Chesapeake Bay resident dolphin population (Engelhaupt et al., 2016).
Harbor Porpoise
    Harbor porpoises inhabit cool temperate-to-subpolar waters, often 
where prey aggregations are concentrated (Watts and Gaskin, 1985). 
Thus, they are frequently found in shallow waters, most often near 
shore, but they sometimes move into deeper offshore waters. Harbor 
porpoises are rarely found in waters warmer than 63 degrees Fahrenheit 
(17 degrees Celsius) (Read 1999) and closely follow the movements of 
their primary prey, Atlantic herring (Gaskin 1992).
    In the western North Atlantic, harbor porpoise range from 
Cumberland Sound on the east coast of Baffin Island, southeast along 
the eastern coast of Labrador to Newfoundland and the Gulf of St. 
Lawrence, then southwest to about 34 degrees North on the coast of 
North Carolina (Waring et al., 2016). During winter (January to March), 
intermediate densities of harbor porpoises can be found in waters off 
New Jersey to North Carolina, and lower densities are found in waters 
off New York to New Brunswick, Canada (Waring et al., 2016). Harbor 
porpoises sighted off the mid-Atlantic during winter include porpoises 
from other western North Atlantic populations (Rosel et al., 1999). 
There does not appear to be a temporally coordinated migration or a 
specific migratory route to and from the Bay of Fundy region (Waring et 
al., 2016). During fall (October to December) and spring (April to 
June), harbor porpoises are widely dispersed from New Jersey to Maine, 
with lower densities farther north and south (LaBrecque et al., 2015).
    Based on stranding reports, passive acoustic recorders, and 
shipboard surveys, harbor porpoise occur in coastal waters primarily in 
winter and spring months, but there is little information on their 
presence in the Chesapeake Bay. They do not appear to be abundant in 
the NAVSTA Norfolk area in most years, but this is confounded by wide 
variations in stranding occurrences over the past decade. In the recent 
HRBT project, zero harbor porpoises were observed near the project area 
(HRCP, Unpublished).
Harbor Seal
    The Western North Atlantic stock of harbor seals occurs in the 
project area. Harbor seal distribution along the U.S. Atlantic coast 
has shifted in recent years, with an increased number of seals reported 
from southern New England to the mid-Atlantic region (DiGiovanni et 
al., 2011; Hayes et al., 2021). Regular sightings of seals in Virginia 
have become a common occurrence in winter and early spring (Costidis et 
al., 2019). Winter haulout sites for harbor seals have been documented 
in the Chesapeake Bay at the CBBT, on the Virginia Eastern Shore, and 
near Oregon Inlet, North Carolina (Waring et al., 2016; Rees et al., 
2016; Jones et al., 2018).
    Harbor seals regularly haul out on rocks around the portal islands 
of the CBBT and on mud flats on the nearby southern tip of the Eastern 
Shore from December through April (Rees et al., 2016; Jones et al., 
2018). Seals captured in 2018 on the Eastern Shore and tagged with 
satellite-tracked tags that lasted from 2 to 5 months spent at least 60 
days in Virginia waters before departing the area. All tagged seals 
returned regularly to the capture site while in Virginia waters, but 
individuals utilized offshore and Chesapeake Bay waters to different 
extents (Ampela et al., 2019). The area that was utilized most heavily 
was near the Eastern Shore capture site, but some seals ranged into the 
Chesapeake Bay. To supplement this information, the HRBT project 
reported seeing zero seals in or around the project area (HRCP, 
Unpublished).
Gray Seal
    The Western North Atlantic stock of gray seal occurs in the project 
area. The western North Atlantic stock is centered in Canadian waters, 
including the Gulf of St. Lawrence and the Atlantic coasts of Nova 
Scotia, Newfoundland, and Labrador, Canada, and the northeast U.S. 
continental shelf (Hayes et al., 2021). Gray seals range south into the 
northeastern United States, with strandings and sightings as far south 
as North Carolina (Hammill et al., 1998; Waring et al., 2004). Gray 
seal distribution along the U.S. Atlantic coast has shifted in recent 
years, with an increased number of seals reported in southern New 
England (DiGiovanni et al., 2011; Kenney R.D., 2019; Waring et al., 
2016). Recent sightings included a gray seal in the lower Chesapeake 
Bay during the winter of 2014 to 2015 (Rees et al., 2016). Along the 
coast of the United States, gray seals are known to pup at three or 
more colonies in Massachusetts and Maine.

Unusual Mortality Events

    An unusual mortality even (UME) is defined under section 410(6) of 
the MMPA as a stranding that is unexpected; involves a significant die-
off of any marine mammal population; and demands immediate response. 
Currently, there are active UMEs for northeast pinnipeds (harbor and 
gray seals) and humpback whales along the east coast.
Northeast Pinniped UME
    Since June 2022, elevated numbers of sick and dead harbor seal and 
gray seal have been documented along the southern and central coast of 
Maine from Biddeford to Boothbay (including Cumberland, Lincoln, Knox, 
Sagadahoc and York Counties). This event has been declared a UME. 
Additional information is available at: https://www.fisheries.noaa.gov/2022-pinniped-unusual-mortality-event-along-maine-coast.
Atlantic Humpback Whale UME
    Since January 2016, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine through Florida. This 
event was declared an UME in 2017 however. A portion of the whales have 
shown evidence of pre-mortem vessel strike; however, this finding is 
not consistent across all whales examined, and additional research is 
needed. Additional information is available at https://www.fisheries.noaa.gov/national/marine-life-distress/2016-2021-humpback-whale-unusual-mortality-event-along-atlantic-coast.

[[Page 14569]]

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. 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, 2019) recommended that marine mammals be divided into hearing 
groups based on directly measured (behavioral or auditory evoked 
potential techniques) or estimated hearing ranges (behavioral response 
data, anatomical modeling, etc.). 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 4.

           Table 4--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
                                                    Generalized hearing
                  Hearing group                           range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)....  7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed   150 Hz to 160 kHz.
 whales, beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises,    275 Hz to 160 kHz.
 Kogia, river dolphins, Cephalorhynchid,
 Lagenorhynchus cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals).  50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions    60 Hz to 39 kHz.
 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.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section provides a discussion of the ways in which 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 whether those 
impacts are reasonably expected to, or reasonably likely to, adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far. The sound level of an area is defined by the 
total acoustical energy being generated by known and unknown sources. 
These sources may include physical (e.g., waves, wind, precipitation, 
earthquakes, ice, atmospheric sound), biological (e.g., sounds produced 
by marine mammals, fish, and invertebrates), and anthropogenic sound 
(e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activity may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.
    In-water construction activities associated with the project would 
include vibratory pile removal, impact and vibratory pile driving, and 
drilling. The sounds produced by these activities fall into one of two 
general sound types: Impulsive and non-impulsive. Impulsive sounds 
(e.g., explosions, gunshots, sonic booms, impact pile driving) are 
typically transient, brief (less than 1 second), broadband, and consist 
of high peak sound pressure with rapid rise time and rapid decay (ANSI 
1986; NIOSH 1998; ANSI 2005; NMFS 2018). Non-impulsive sounds (e.g., 
aircraft, machinery operations such as drilling or dredging, vibratory 
pile driving, and active sonar systems) can be broadband, narrowband or 
tonal, brief or prolonged (continuous or intermittent), and typically 
do not have the high peak sound pressure with raid rise/decay time that 
impulsive sounds do (ANSI 1995; NIOSH 1998; NMFS 2018). The distinction 
between these two sound types is important because they have differing 
potential to cause physical effects, particularly with regard to 
hearing (e.g., Ward 1997 in Southall et al., 2007).
    Impact hammers operate by repeatedly dropping a heavy piston onto a 
pile to drive the pile into the substrate. Sound generated by impact 
hammers is

[[Page 14570]]

characterized by rapid rise times and high peak levels, a potentially 
injurious combination (Hastings and Popper 2005). Vibratory hammers 
install piles by vibrating them and allowing the weight of the hammer 
to push them into the sediment. The vibrations produced also cause 
liquefaction of the substrate surrounding the pile, enabling the pile 
to be extracted or driven into the ground more easily. Vibratory 
hammers produce significantly less sound than impact hammers. Peak 
sound pressure levels (SPLs) may be 180 dB or greater, but are 
generally 10 to 20 dB lower than SPLs generated during impact pile 
driving of the same-sized pile (Oestman et al., 2009). Rise time is 
slower, reducing the probability and severity of injury, and sound 
energy is distributed over a greater amount of time (Nedwell and 
Edwards 2002; Carlson et al., 2005). As mentioned previously, drilling 
is considered a continuous source, similar to vibratory pile driving. 
The drilling may be used before driving piles in order to facilitate 
pile driving and hence is referred to as ``pre-drilling''. For the 
proposed project, the drilling apparatus utilized would vary depending 
on the different applications during in-water construction activities. 
Drilling would be used as necessary to remove sand with shell fragments 
or any obstructions in order to accelerate pile driving.
    The likely or possible impacts of the Navy's proposed activity on 
marine mammals could involve both non-acoustic and acoustic stressors. 
Potential non-acoustic stressors could result from the physical 
presence of the equipment and personnel; however, any impacts to marine 
mammals are expected to be primarily acoustic in nature. Acoustic 
stressors include effects of heavy equipment operation during pile 
driving, removal and drilling.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile driving or drilling is the primary means by which 
marine mammals may be harassed from the Navy's specified activity. In 
general, animals exposed to natural or anthropogenic sound may 
experience physical and psychological effects, ranging in magnitude 
from none to severe (Southall et al., 2007). In general, exposure to 
pile driving or drilling noise has the potential to result in auditory 
threshold shifts and behavioral reactions (e.g., avoidance, temporary 
cessation of foraging and vocalizing, changes in dive behavior). 
Exposure to anthropogenic noise can also lead to non-observable 
physiological responses such an increase in stress hormones. Additional 
noise in a marine mammal's habitat can mask acoustic cues used by 
marine mammals to carry out daily functions such as communication and 
predator and prey detection. The effects of pile driving or drilling 
noise on marine mammals are dependent on several factors, including, 
but not limited to, sound type (e.g., impulsive vs. non-impulsive), the 
species, age and sex class (e.g., adult male vs. mom with calf), 
duration of exposure, the distance between the pile and there animal, 
received levels, behavior at time of exposure, and previous history 
with exposure (Wartzok et al., 2004; Southall et al., 2007). Here we 
discuss physical auditory effects (threshold shifts) followed by 
behavioral effects and potential impacts on habitat.
    NMFS defines a noise-induced threshold shift (TS) as a change, 
usually an increase, in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). The amount of 
threshold shift is customarily expressed in decibels (dB). A TS can be 
permanent or temporary. As described in NMFS (2018), there are numerous 
factors to consider when examining the consequence of TS, including, 
but not limited to, the signal temporal pattern (e.g., impulsive or 
non-impulsive), likelihood an individual would be exposed for a long 
enough duration or to a high enough level to induce a TS, the magnitude 
of the TS, time to recovery (seconds to minutes or hours to days), the 
frequency range of the exposure (i.e., spectral content), the hearing 
and vocalization frequency range of the exposed species relative to the 
signal's frequency spectrum (i.e., how an animal uses sound within the 
frequency band of the signal; e.g., Kastelein et al., 2014), and the 
overlap between the animal and the source (e.g., spatial, temporal, and 
spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals indicate that a 40 dB threshold 
shift approximates PTS onset (see Ward et al., 1958, 1959; Ward 1960; 
Kryter et al., 1966; Miller 1974; Ahroon et al., 1996; Henderson et 
al., 2008). PTS levels for marine mammals are estimates, as with the 
exception of a single study unintentionally inducing PTS in a harbor 
seal (Kastak et al., 2008), there are no empirical data measuring PTS 
in marine mammals largely due to the fact that, for various ethical 
reasons, experiments involving anthropogenic noise exposure at levels 
inducing PTS are not typically pursued or authorized (NMFS 2018).
    Temporary Threshold Shift (TTS)--TTS is a temporary, reversible 
increase in the threshold of audibility at a specified frequency or 
portion of an individual's hearing range above a previously established 
reference level (NMFS 2018). Based on data from cetacean TTS 
measurements (see Southall et al., 2007), a TTS of 6 dB is considered 
the minimum threshold shift clearly larger than any day-to-day or 
session-to-session variation in a subject's normal hearing ability 
(Schlundt et al., 2000; Finneran et al., 2000, 2002). As described in 
Finneran (2015), marine mammal studies have shown the amount of TTS 
increases with cumulative sound exposure level (SELcum) in 
an accelerating fashion: At low exposures with lower SELcum, 
the amount of TTS is typically small and the growth curves have shallow 
slopes. At exposures with higher SELcum, the growth curves 
become steeper and approach linear relationships with the noise SEL.
    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 takes place during a time when the animal 
is traveling through the open ocean, 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 a time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that 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 we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin, beluga whale (Delphinapterus leucas), harbor 
porpoise, and Yangtze finless porpoise (Neophocoena asiaeorientalis) 
and five species of pinnipeds exposed to a limited number of sound 
sources (i.e., mostly tones and

[[Page 14571]]

octave-band noise) in laboratory settings (Finneran 2015). TTS was not 
observed in trained spotted (Phoca largha) and ringed (Pusa hispida) 
seals exposed to impulsive noise at levels matching previous 
predictions of TTS onset (Reichmuth et al., 2016). In general, harbor 
seals and harbor porpoises have a lower TTS onset than other measured 
pinniped or cetacean species (Finneran 2015). Additionally, the 
existing marine mammal TTS data come from a limited number of 
individuals within these species. No data are available on noise-
induced hearing loss for mysticetes. For summaries of data on TTS in 
marine mammals or for further discussion of TTS onset thresholds, 
please see Southall et al., (2007), Finneran and Jenkins (2012), 
Finneran (2015), and Table 5 in NMFS (2018). Installing piles for this 
project requires a combination of drilling, impact pile driving and 
vibratory pile driving. For this project, these activities would not 
occur at the same time and there would be pauses in activities 
producing the sound during each day. Given these pauses and that many 
marine mammals are likely moving through the ensonified area and not 
remaining for extended periods of time, the potential for TS declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
removal also has the potential to behaviorally disturb marine mammals. 
Available studies show wide variation in response to underwater sound; 
therefore, it is difficult to predict specifically how any given sound 
in a particular instance might affect marine mammals perceiving the 
signal. If a marine mammal does react briefly to an underwater sound by 
changing its behavior or moving a small distance, the impacts of the 
change are unlikely to be significant to the individual, let alone the 
stock or population. However, if a sound source displaces marine 
mammals from an important feeding or breeding area for a prolonged 
period, impacts on individuals and populations could be significant 
(e.g., Lusseau and Bejder 2007; Weilgart 2007; NRC 2005).
    Disturbance may result in 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 sound sources are located. 
Pinnipeds may increase their haul out time, possibly to avoid in-water 
disturbance (Thorson and Reyff 2006). Behavioral responses to sound are 
highly variable and context-specific and any reactions depend on 
numerous intrinsic and extrinsic factors (e.g., species, state of 
maturity, experience, current activity, reproductive state, auditory 
sensitivity, time of day), as well as the interplay between factors 
(e.g., Richardson et al., 1995; Wartzok et al., 2003; Southall et al., 
2007; Weilgart 2007; Archer et al., 2010). Behavioral reactions can 
vary not only among individuals but also within an individual, 
depending on previous experience with a sound source, context, and 
numerous other factors (Ellison et al., 2012), and can vary depending 
on characteristics associated with the sound source (e.g., whether it 
is moving or stationary, number of sources, distance from the source). 
In general, pinnipeds seem more tolerant of, or at least habituate more 
quickly to, potentially disturbing underwater sound than do cetaceans, 
and generally seem to be less responsive to exposure to industrial 
sound than most cetaceans. Please see Appendices B and C of Southall et 
al. (2007) and Gomez et al. (2016) for reviews of studies involving 
marine mammals behavioral responses to sound.
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. It is important to note that 
habituation is appropriately considered as a ``progressive reduction in 
response to stimuli that are perceived as neither aversive nor 
beneficial,'' rather than as, more generally, moderation in response to 
human disturbance (Bejder et al., 2009). The opposite process is 
sensitization, when an unpleasant experience leads to subsequent 
responses, often in the form of avoidance, at a lower level of 
exposure.
    As noted above, behavioral state may affect the type of response. 
For example, animals that are resting may show greater behavioral 
change in response to disturbing sound levels than animals that are 
highly motivated to remain in an area for feeding (Richardson et al., 
1995; National Research Council (NRC), 2003; Wartzok et al., 2003). 
Controlled experiments with captive marine mammals have showed 
pronounced behavioral reactions, including avoidance of loud sound 
sources (Ridgway et al., 1997; Finneran et al., 2003). Observed 
responses of wild marine mammals to loud pulsed sound sources 
(typically seismic airguns or acoustic harassment devices) have been 
varied but often consist of avoidance behavior or other behavioral 
changes suggesting discomfort (Morton and Symonds, 2002; see also 
Richardson et al., 1995; Nowacek et al., 2007).
    Available studies show wide variation in response to underwater 
sound; therefore, it is difficult to predict specifically how any given 
sound in a particular instance might affect marine mammals perceiving 
the signal. If a marine mammal does react briefly to an underwater 
sound by changing its behavior or moving a small distance, the impacts 
of the change are unlikely to be significant to the individual, let 
alone the stock or population. However, if a sound source displaces 
marine mammals from an important feeding or breeding area for a 
prolonged period, impacts on individuals and populations could be 
significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007; NRC, 
2005). However, there are broad categories of potential response, which 
we describe in greater detail here, that include alteration of dive 
behavior, alteration of foraging behavior, effects to breathing, 
interference with or alteration of vocalization, avoidance, and flight.
    Changes in dive behavior can vary widely and may consist of 
increased or decreased dive times and surface intervals as well as 
changes in the rates of ascent and descent during a dive (e.g., Frankel 
and Clark, 2000; Costa et al., 2003; Ng and Leung, 2003; Nowacek et 
al., 2004; Goldbogen et al., 2013a,b). Variations in dive behavior may 
reflect interruptions in biologically significant activities (e.g., 
foraging) or they may be of little biological significance. The impact 
of an alteration to dive behavior resulting from an acoustic exposure 
depends on what the animal is doing at the time of the exposure and the 
type and magnitude of the response.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al., 
2007). A determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort

[[Page 14572]]

and success, and the life history stage of the animal.
    Variations in respiration naturally vary with different behaviors 
and alterations to breathing rate as a function of acoustic exposure 
can be expected to co-occur with other behavioral reactions, such as a 
flight response or an alteration in diving. However, respiration rates 
in and of themselves may be representative of annoyance or an acute 
stress response. Various studies have shown that respiration rates may 
either be unaffected or could increase, depending on the species and 
signal characteristics, again highlighting the importance in 
understanding species differences in the tolerance of underwater noise 
when determining the potential for impacts resulting from anthropogenic 
sound exposure (e.g., Kastelein et al., 2001, 2005, 2006; Gailey et 
al., 2007).
    Marine mammals vocalize for different purposes and across multiple 
modes, such as whistling, echolocation click production, calling, and 
singing. Changes in vocalization behavior in response to anthropogenic 
noise can occur for any of these modes and may result from a need to 
compete with an increase in background noise or may reflect increased 
vigilance or a startle response. For example, in the presence of 
potentially masking signals, humpback whales and killer whales have 
been observed to increase the length of their songs (Miller et al., 
2000; Fristrup et al., 2003; Foote et al., 2004), while right whales 
have been observed to shift the frequency content of their calls upward 
while reducing the rate of calling in areas of increased anthropogenic 
noise (Parks et al., 2007). In some cases, animals may cease sound 
production during production of aversive signals (Bowles et al., 1994).
    Avoidance is the displacement of an individual from an area or 
migration path as a result of the presence of a sound or other 
stressors, and is one of the most obvious manifestations of disturbance 
in marine mammals (Richardson et al., 1995). For example, gray whales 
are known to change direction--deflecting from customary migratory 
paths--in order to avoid noise from seismic surveys (Malme et al., 
1984). Avoidance may be short-term, with animals returning to the area 
once the noise has ceased (e.g., Bowles et al., 1994; Goold, 1996; 
Stone et al., 2000; Morton and Symonds, 2002; Gailey et al., 2007). 
Longer-term displacement is possible, however, which may lead to 
changes in abundance or distribution patterns of the affected species 
in the affected region if habituation to the presence of the sound does 
not occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann 
et al., 2006).
    A flight response is a dramatic change in normal movement to a 
directed and rapid movement away from the perceived location of a sound 
source. The flight response differs from other avoidance responses in 
the intensity of the response (e.g., directed movement, rate of 
travel). Relatively little information on flight responses of marine 
mammals to anthropogenic signals exist, although observations of flight 
responses to the presence of predators have occurred (Connor and 
Heithaus, 1996, Bowers et al., 2018). The result of a flight response 
could range from brief, temporary exertion and displacement from the 
area where the signal provokes flight to, in extreme cases, marine 
mammal strandings (Evans and England, 2001). However, it should be 
noted that response to a perceived predator does not necessarily invoke 
flight (Ford and Reeves, 2008), and whether individuals are solitary or 
in groups may influence the response.
    Behavioral disturbance can also impact marine mammals in more 
subtle ways. Increased vigilance may result in costs related to 
diversion of focus and attention (i.e., when a response consists of 
increased vigilance, it may come at the cost of decreased attention to 
other critical behaviors such as foraging or resting). These effects 
have generally not been demonstrated for marine mammals, but studies 
involving fish and terrestrial animals have shown that increased 
vigilance may substantially reduce feeding rates (e.g., Beauchamp and 
Livoreil, 1997). In addition, chronic disturbance can cause population 
declines through reduction of fitness (e.g., decline in body condition) 
and subsequent reduction in reproductive success, survival, or both 
(e.g., Harrington and Veitch, 1992). However, Ridgway et al. (2006) 
reported that increased vigilance in bottlenose dolphins exposed to 
sound over a 5 day period did not cause any sleep deprivation or stress 
effects.
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing, on a diel cycle (24-hour cycle). Disruption 
of such functions resulting from reactions to stressors such as sound 
exposure are more likely to be significant if they last more than one 
diel cycle or recur on subsequent days (Southall et al., 2007). 
Consequently, a behavioral response lasting less than one day and not 
recurring on subsequent days is not considered particularly severe 
unless it could directly affect reproduction or survival (Southall et 
al., 2007). Note that there is a difference between multi-day 
substantive behavioral reactions and multi-day anthropogenic 
activities. For example, just because an activity lasts for multiple 
days does not necessarily mean that individual animals are either 
exposed to activity-related stressors for multiple days or, further, 
exposed in a manner resulting in sustained multi-day substantive 
behavioral responses.
    Stress responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral responses, autonomic nervous system responses, 
neuroendocrine responses, or immune responses (e.g., Seyle, 1950; 
Moberg, 2000). In many cases, an animal's first and sometimes most 
economical (in terms of energetic costs) response is behavioral 
avoidance of the potential stressor. Autonomic nervous system responses 
to stress typically involve changes in heart rate, blood pressure, and 
gastrointestinal activity. These responses have a relatively short 
duration and may or may not have a significant long-term effect on an 
animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg, 1987; Blecha, 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al., 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and ``distress'' is the cost of 
the response. During a stress response, an animal uses glycogen stores 
that can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This state of 
distress will last until the animal replenishes its energetic reserves 
sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well-studied through 
controlled experiments and for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996; Hood et al.,

[[Page 14573]]

1998; Jessop et al., 2003; Krausman et al., 2004; Lankford et al., 
2005). Stress responses due to exposure to anthropogenic sounds or 
other stressors and their effects on marine mammals have also been 
reviewed (Fair and Becker, 2000; Romano et al., 2002b) and, more 
rarely, studied in wild populations (e.g., Romano et al., 2002a). For 
example, Rolland et al. (2012) found that noise reduction from reduced 
ship traffic in the Bay of Fundy was associated with decreased stress 
in North Atlantic right whales. These and other studies lead to a 
reasonable expectation that some marine mammals will experience 
physiological stress responses upon exposure to acoustic stressors and 
that it is possible that some of these would be classified as 
``distress.'' In addition, any animal experiencing TTS would likely 
also experience stress responses (NRC, 2003), however distress is an 
unlikely result of this project based on observations of marine mammals 
during previous, similar construction projects.
    Acoustic Masking--Sound can disrupt behavior through masking, or 
interfering with, and animal's ability to detect, recognize, or 
discriminate between acoustic signals of interest (e.g., those used for 
intraspecific communication and social interactions, prey detection, 
predator avoidance, navigation) (Richardson et al., 1995). Masking 
occurs when the receipt of a sound is interfered with by another 
coincident sound at similar frequencies and at similar or higher 
intensity, and may occur whether the sound is natural (e.g., snapping 
shrimp, wind, waves, precipitation) or anthropogenic (e.g., pile 
driving, shipping, sonar, seismic exploration) in origin. The ability 
of a noise source to mask biologically important sounds depends on the 
characteristics of both the noise source and the signal of interest 
(e.g., signal-to-noise ratio, temporal variability, direction), in 
relation to each other and to an animal's hearing abilities (e.g., 
sensitivity, frequency range, critical rations, frequency 
discrimination, directional discrimination, age or TTS hearing loss), 
and existing ambient noise and propagation conditions. Masking of 
natural sounds can result when human activities produce high levels of 
background sound at frequencies important to marine mammals. 
Conversely, if the background level of underwater sound is high (e.g., 
on a day with strong wind and high waves), an anthropogenic sound 
source would not be detectable as far away as would be possible under 
quieter conditions and would itself be masked.
    Airborne Acoustic Effects--Although pinnipeds are known to haul-out 
regularly on man-made objects, such as the nearby Chesapeake Bay Bridge 
Tunnel, we believe that incidents of take resulting solely from 
airborne sound are unlikely due to the sheltered proximity between the 
proposed project area and these haulout sites (over 16 miles (26 km)). 
There is a possibility that an animal could surface in-water, but with 
head out, within the area in which airborne sound exceeds relevant 
thresholds and thereby be exposed to levels of airborne sound that we 
associate with harassment, but any such occurrence would likely be 
accounted for in our estimate of incidental take from underwater sound. 
Therefore, authorization of incidental take resulting from airborne 
sound for pinnipeds is not warranted, and airborne sound is not 
discussed further here. Cetaceans are not expected to be exposed to 
airborne sounds that would result in harassment as defined under the 
MMPA.

Marine Mammal Habitat Effects

    The Navy's construction activities could have localized, temporary 
impacts on marine mammal habitat by increasing in-water sound pressure 
levels and slightly decreasing water quality. However, since the focus 
of the proposed action is pile driving and drilling, no net habitat 
loss is expected as the new Pier 3 will be immediately north of the 
existing Pier 3 and, once complete, the current Pier 3 will be 
demolished. Construction activities are of short duration and would 
likely have temporary impacts on marine mammal habitat through 
increases in underwater sounds. Increased noise levels may affect the 
acoustic habitat (see masking discussion above) and adversely affect 
marine mammal prey in the vicinity of the project area (see discussion 
below). During pile driving activities, elevated levels of underwater 
noise would ensonify the project area where both fishes and marine 
mammals may occur and could affect foraging success. Additionally, 
marine mammals may avoid the area during construction, however 
displacement due to noise is expected to be temporary and is not 
expected to result in long-term effects to the individuals or 
populations.
    Temporary and localized reduction in water quality will occur 
because of in-water construction activities as well. Most of this 
effect will occur during the installation and removal of piles when 
bottom sediments are disturbed. The installation of piles will disturb 
bottom sediments and may cause a temporary increase in suspended 
sediment in the project area. In general, turbidity associated with 
pile installation is localized to about 25-ft (7.6 meter) radius around 
the pile (Everitt et al., 1980). Cetaceans are not expected to be close 
enough to the pile driving areas to experience effects of turbidity, 
and any pinnipeds could avoid localized areas of turbidity. Therefore, 
we expect the impact from increased turbidity levels to be discountable 
to marine mammals and do not discuss it further.
    In-Water Construction Effects on Potential Foraging Habitat--The 
proposed activities would not result in permanent impacts to habitats 
used directly by marine mammals except for the actual footprint of the 
new Pier 3. The total seafloor area affected by pile installation and 
removal is a very small area compared to the vast foraging area 
available to marine mammals in the project area and lower Chesapeake 
Bay. Pile extraction and installation may have impacts on benthic 
invertebrate species primarily associated with disturbance of sediments 
that may cover or displace some invertebrates. The impacts will be 
temporary and highly localized, and no habitat will be permanently 
displaced by construction. Therefore, it is expected that impacts on 
foraging opportunities for marine mammals due to the demolition and 
reconstruction of Pier 3 would be minimal.
    It is possible that avoidance by potential prey (i.e., fish) in the 
immediate area may occur due to temporary loss of this foraging 
habitat. The duration of fish avoidance of this area after pile driving 
stops is unknown, but we anticipate a rapid return to normal 
recruitment, distribution and behavior. Any behavioral avoidance by 
fish of the disturbed area would still leave large areas of fish and 
marine mammal foraging habitat in the nearby vicinity in the project 
area and lower Chesapeake Bay.
    Effects on Potential Prey--Sound may affect marine mammals through 
impacts on the abundance, behavior, or distribution of prey species 
(e.g., fish). Marine mammal prey varies by species, season, and 
location. Here, we describe studies regarding the effects of noise on 
known marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009). 
Depending on their hearing anatomy and peripheral sensory structures, 
which vary among species, fishes hear

[[Page 14574]]

sounds using pressure and particle motion sensitivity capabilities and 
detect the motion of surrounding water (Fay et al., 2008). The 
potential effects of noise on fishes depends on the overlapping 
frequency range, distance from the sound source, water depth of 
exposure, and species-specific hearing sensitivity, anatomy, and 
physiology. Key impacts to fishes may include behavioral responses, 
hearing damage, barotrauma (pressure-related injuries), and mortality.
    Fish react to sounds which are especially strong and/or 
intermittent low-frequency sounds, and behavioral responses such as 
flight or avoidance are the most likely effects. Short duration, sharp 
sounds can cause overt or subtle changes in fish behavior and local 
distribution. The reaction of fish to noise depends on the 
physiological state of the fish, past exposures, motivation (e.g., 
feeding, spawning, migration), and other environmental factors. 
Hastings and Popper (2005) identified several studies that suggest fish 
may relocate to avoid certain areas of sound energy. Additional studies 
have documented effects of pile driving on fish, although several are 
based on studies in support of large, multiyear bridge construction 
projects (e.g., Scholik and Yan, 2001, 2002; Popper and Hastings, 
2009). Several studies have demonstrated that impulse sounds might 
affect the distribution and behavior of some fishes, potentially 
impacting foraging opportunities or increasing energetic costs (e.g., 
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al., 
1992; Santulli et al., 1999; Paxton et al., 2017). However, some 
studies have shown no or slight reaction to impulse sounds (e.g., Pena 
et al., 2013; Wardle et al., 2001; Jorgenson and Gyselman, 2009; Cott 
et al., 2012).
    SPLs of sufficient strength have been known to cause injury to fish 
and fish mortality. However, in most fish species, hair cells in the 
ear continuously regenerate and loss of auditory function likely is 
restored when damaged cells are replaced with new cells. Halvorsen et 
al. (2012a) showed that a TTS of 4-6 dB was recoverable within 24 hours 
for one species. Impacts would be most severe when the individual fish 
is close to the source and when the duration of exposure is long. 
Injury caused by barotrauma can range from slight to severe and can 
cause death, and is most likely for fish with swim bladders. Barotrauma 
injuries have been documented during controlled exposure to impact pile 
driving (Halvorsen et al., 2012b; Casper et al., 2013).
    The most likely impact to fish from pile driving activities at the 
project areas would be temporary behavioral avoidance of the area. The 
duration of fish avoidance of an area after pile driving stops is 
unknown, but a rapid return to normal recruitment, distribution and 
behavior is anticipated.
    The area impacted by the project is relatively small compared to 
the available habitat in the remainder of the project area and the 
lower Chesapeake Bay, and there are no areas of particular importance 
that would be impacted by this project. Any behavioral avoidance by 
fish of the disturbed area would still leave significantly large areas 
of fish and marine mammal foraging habitat in the nearby vicinity. As 
described in the preceding, the potential for the Navy's construction 
to affect the availability of prey to marine mammals or to meaningfully 
impact the quality of physical or acoustic habitat is considered to be 
insignificant.

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 
determinations.
    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) and 
drilling 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, primarily for high- 
and low-frequency species and phocids because predicted auditory injury 
zones are larger than for mid-frequency species. However, auditory 
injury is unlikely to occur for low- and mid- frequency species as 
proposed shutdown zones encompass the entirely of the auditory injury 
zones for all proposed activities (see Proposed Mitigation section). 
The proposed mitigation and monitoring measures are expected to 
minimize the severity of the taking to the extent practicable.
    As described previously, no serious injury or mortality is 
anticipated or proposed to be authorized for this activity. Below we 
describe how the proposed take numbers are estimated.
    For acoustic impacts, 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) the number of days of activities. We note 
that while these factors can contribute to a basic calculation to 
provide an initial prediction of potential 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 estimates.

Acoustic Thresholds

    NMFS recommends the use of 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--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 or exposure context (e.g., frequency, predictability, duty 
cycle, duration of the exposure, signal-to-noise ratio, distance to the 
source), the environment (e.g., bathymetry, other noises in the area, 
predators in the area), and the receiving animals (hearing, motivation, 
experience, demography, life stage, depth) and can be difficult to 
predict (e.g., Southall et al., 2007, 2021, Ellison et al., 2012). 
Based on what the available science indicates and the practical need to 
use a threshold based on a metric that is both predictable and 
measurable for most activities, NMFS typically uses a generalized 
acoustic threshold based on received level to estimate the onset of 
behavioral harassment. NMFS generally predicts that marine mammals are 
likely to be behaviorally harassed in a manner considered to be Level B 
harassment when exposed to underwater

[[Page 14575]]

anthropogenic noise above root-mean-squared pressure received levels 
(RMS SPL) of 120 dB (referenced to 1 micropascal (re 1 [mu]Pa)) for 
continuous (e.g., vibratory pile-driving, drilling) and above RMS SPL 
160 dB re 1 [mu]Pa for non-explosive impulsive (e.g., impact pile 
driving) or intermittent (e.g., scientific sonar) sources.
    The Navy's construction includes the use of continuous (vibratory 
pile driving/removal, drilling) and impulsive (impact pile driving) 
sources, and therefore the 120 and 160 dB re 1 [mu]Pa (rms) are 
applicable.
    Level A Harassment--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). As 
previously noted, the Navy's proposed activity includes the use of non-
impulsive (vibratory pile driving/removal, drilling) and impulsive 
(impact pile 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: 
www.fisheries.noaa.gov/national/marine-mammal-p-rotection/marine-mammal-acoustic-technical-guidance.

                     Table 5--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 are used in estimating the area ensonified above the 
acoustic thresholds, including source levels and transmission loss 
coefficient.
    In order to calculate the distances to the Level A harassment and 
the Level B harassment sound thresholds for the methods and piles being 
used in this project, NMFS used acoustic monitoring data from other 
locations to develop proxy source levels for various pile types (Table 
6). Generally we choose source levels from similar pile types and 
locations (e.g., geology, bathymetry) similar to the project. At this 
time, NMFS is not aware of reliable source levels available for 
polymeric piles using vibratory pile installation, therefore source 
levels for timber pile driving were used as a proxy. Vibratory pile 
driving of polymeric piles expected to occur under the 2022 IHA has yet 
to occur and therefore has not been measured. Similarly, the following 
proxies were used as source levels for piles where no data was 
available: Source levels from the 48-inch steel pile from Naval Base 
Kitsap at Bangor, Washington (Caltrans 2020) was used as a proxy for 42 
inch steel pipe piles (impact); the 30-inch steel pipe pile was used as 
a proxy for the 28 inch steel sheet pile (impact and vibratory); source 
levels for timber piles were used as a proxy for concrete as they are 
expected to have similar sound levels as they are similarly sized, non-
metallic, and will be removed using the same methods.
    Very little information is available regarding source levels for 
in-water drilling activities associated with nearshore pile 
installation. Measurements made during a pile drilling project in 1-5 m 
(3-16 ft) depth at Santa Rosa Island, CA, by Dazey et al. (2012) appear 
to provide the best available proxy source levels for proposed 
activities. Dazey et al. (2012) reported average rms source levels 
ranging from 151 to 157 db re 1 [mu]Pa during 62 days that spanned all 
related drilling activities during a single season.

                                 Table 6--Project Sound Source Levels and Proxy Source Levels Used for Acoustic Modeling
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  Peak SPL (re 1   RMS SPL (re 1      SEL (re 1
        Pile type                 Pile size (inch)                Method          [mu]Pa (rms))    [mu]Pa (rms))    [mu]Pa (rms))          Source
--------------------------------------------------------------------------------------------------------------------------------------------------------
Steel Pipe Pile.........  42.............................  Impact..............              213              190              177  Caltrans 2020.
                                                           Vibratory...........              N/A              168              N/A  Sitka 2017.
Steel Sheet.............  28.............................  Impact \1\..........              211              196              181  NAVFAC SW 2020.
                                                           Vibratory \2\.......              N/A              167              167  Navy 2015.
Concrete Pile...........  24.............................  Impact..............              189              176              163  Illingworth and
                                                                                                                                     Rodkin 2017.
                                                           Vibratory Removal                 185              162              157  Caltrans 2020.
                                                            \3\.
Concrete Pile...........  18.............................  Impact \3\..........              185              166              154  Caltrans 2020.
                                                           Vibratory Removal                 185              162              157  Caltrans 2020.
                                                            \4\.
Polymeric Pile..........  13.............................  Impact..............              177              153  ...............  Denes et al., 2016.
                                                           Vibratory \5\.......              185              162              157  Caltrans 2020.

[[Page 14576]]

 
Timber Pile.............  14.............................  Vibratory Install/                185              162              157  Caltrans 2020.
                                                            Removal.
N/A \6\.................  ``Multiple pile sizes'' \6\....  Drilling............              N/A              154              N/A  Dazey et al., 2012.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ A source level value for impact pile driving of 28-inch steel sheet piles could not be found so a value for a 30-inch steel pipe pile has been used
  as a proxy (NAVFAC SW, 2020 [p.A-4]).
\2\ A source level value for vibratory pile driving of 28-inch steel sheet piles could not be found so a value for a 30-inch steel pipe pile has been
  used as a proxy (Navy, 2015 [p. 14]).
\3\ Data on vibratory extraction of concrete piles is not available, however source levels are expected to be similar to the levels produced by timber
  piles as they are similar in size, material and removal method.
\4\ Proxy data for 18-inch octagonal piles.
\5\ Vibratory proxy for polymeric/plastic piles is unavailable; we assume SPL to be consistent with timber.
\6\ See Table 2 for pile types/size that may use drilling, as needed.


                                                 Table 7--Source Level Matrix for Concurrent Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    42-inch      28-inch      14-inch      14-inch      24-inch      18-inch      14-inch
           Pile diameter                           steel pipe   steel pipe     timber     polymeric     concrete     concrete      timber      Multiple
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             SSL          168          167          162          162          162          162          162          154
42-inch Steel Pipe.................          168          171          171          169          169          169          169          169          168
28-inch Steel Pipe.................          167          171          170          168          168          168          168          168          167
14-inch Timber.....................          162          169          168          165          165          165          165          165          163
14-inch Polymeric..................          162          169          168          165          165          165          165          165          163
24-inch Concrete...................          162          169          168          165          165          165          165          165          163
18-inch Concrete...................          162          169          168          165          165          165          165          165          163
14-inch Timber.....................          162          169          168          165          165          165          165          165          163
Multiple...........................          154          168          167          163          163          163          163          163          157
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The ensonified area associated with Level A harassment is more 
technically challenging to predict due to the need to account for a 
duration component. Therefore, NMFS developed an optional User 
Spreadsheet tool to accompany the Technical Guidance that can be used 
to relatively simply predict an isopleth distance for use in 
conjunction with marine mammal density or occurrence to help predict 
potential takes. We note that because of some of the assumptions 
included in the methods underlying this optional tool, we anticipate 
that the resulting isopleth estimates are typically going to be 
overestimates of some degree, which may result in an overestimate of 
potential take by Level A harassment. However, this optional tool 
offers the best way to estimate isopleth distances when more 
sophisticated modeling methods are not available or practical. For 
stationary sources, such as pile driving, removal, and drilling, the 
optional User Spreadsheet tool predicts the distance at which, if a 
marine mammal remained at that distance for the duration of the 
activity, it would be expected to incur PTS. Inputs used in the 
optional User Spreadsheet tool are reported in Table 1 and Table 2, and 
source levels used in the User Spreadsheet are reported in Table 6. The 
resulting isopleths are reported in Table 7 (impact pile driving), 
Table 8 (vibratory pile driving/removal, and drilling), and Table 9 
(concurrent pile driving scenarios) below.

                                        Table 8--Level A and Level B Harassment Isopleths for Impact Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                 Level A harassment isopleths (m)              Level B
         Year                Pile driving site                     Source              ---------------------------------------------------- (behavioral)
                                                                                             LF           MF           HF        Phocids         (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Year 2...............  CEP-176.....................  42-inch Steel Pipe...............        1,482           53        1,766          793         1,000
                                                     28-inch Steel Sheets.............        1,783           63        2,123          954         2,512
                       CEP-175.....................  13-inch Polymeric Piles..........           17            1           20            9             3
                       CEP-102.....................  24-inch Square Precast Concrete..          117            4          139           63           117
                                                     18-inch Square Precast Concrete..            7            0            9            4            25
                       Pier 3 (bearing piles)......  24-inch Square Precast Concrete..          254            9          302          136           117
Year 3...............  Pier 3 (Fender Piles).......  24-inch Square Precast Concrete..           37            1           44           20           117
                                                     18-inch Steel Pipe...............          661           24          788          354            25
                       CEP-102.....................  42-inch Steel Pipe...............        1,002           36        1,193          536         1,000
                                                     28-inch Steel Sheet..............        1,783           63        2,123          954         2,512
Year 4...............  CEP-102.....................  24-inch Square Precast Concrete..          117            4          139           63           117
                                                     18-inch Square Precast Concrete..            7            0            9            4            25
                                                     42-inch Steel Pipe...............        1,002           36        1,193          536         1,000
                                                     28-inch Steel Sheet..............        1,783           63        2,123          954         2,512
Year 5...............  CEP-102.....................  24-inch Square Precast Concrete..          117            4          139           63           117
                                                     18-inch Square Precast Concrete..            7            0            9            4            25
--------------------------------------------------------------------------------------------------------------------------------------------------------


       Table 9--Level A and Level B Harassment Isopleths for Vibratory Pile Driving, Removal and Drilling
----------------------------------------------------------------------------------------------------------------
                                                        Level A harassment isopleths (m) \1\           Level B
  Year      Pile driving          Source        ----------------------------------------------------  behavioral
                site                                  LF           MF           HF        Phocids        (m)
----------------------------------------------------------------------------------------------------------------
Year 2..  CEP-176........  42-inch Steel Pipe            127           11          188           77       15,849
                            (Vibratory).
                           28-inch Steel Sheet           100            9          147           61       13,594
                            (Vibratory).
          CEP-175........  13-inch Polymeric              15            1           22            9        6,310
                            Piles (Vibratory).
          CEP-102........  24-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).

[[Page 14577]]

 
                           18-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).
Year 3..  Pier 3 (Fender   24-inch Square                  1            0            1            1        1,848
           Piles).          Precast Concrete
                            (Drilling).
          CEP-102........  42-inch Steel Pipe             80            7          118           49       15,849
                            (Vibratory Install).
                           28-inch Steel Sheet           100            9          147           61       13,594
                            Piles (Vibratory).
                           18-inch Square                 35            3           51           21        6,310
                            Precast Concrete
                            (Vibratory
                            Extraction).
Year 4..  CEP-102........  24-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).
                           14-inch Timber                 68            6          101           41        6,310
                            (Vibratory
                            Extraction).
                           18-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).
                           42-inch Steel Pipe             80            7          118           49       15,849
                            (Vibratory).
                           28-inch Steel Sheet           100            9          147           61       13,594
                            (Vibratory).
                           18-inch Square                 35            3           51           21        6,310
                            Precast Concrete
                            (Vibratory
                            Extraction).
          Existing Pier 3  24-inch Square                 42            4           62           25        6,310
                            Precast Concrete
                            (Vibratory
                            Extraction).
                           16-inch and 18-inch            37            3           55           23        6,310
                            Square Precast
                            Concrete (Vibratory
                            Extraction).
Year 5..  CEP-102........  24-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).
                           18-inch Square                  1            0            1            0        1,848
                            Precast Concrete
                            (Drilling).
          Existing Pier 3  16-inch and 18-inch            37            3           55           23        6,310
                            Square Precast
                            Concrete (Vibratory
                            Extraction).
----------------------------------------------------------------------------------------------------------------


      Table 10--Level A and Level B Harassment Isopleths for Concurrent Pile Driving and Drilling Scenarios
----------------------------------------------------------------------------------------------------------------
                                                          Level A harassment isopleths (m)             Level B
  Year      Pile driving          Source        ----------------------------------------------------  behavioral
                site                                  LF           MF           HF        Phocids        (m)
----------------------------------------------------------------------------------------------------------------
2.......  CEP-176          Install of 42-inch            549           49          811          334       25,119
           Bulkhead.        steel pipe and 28-
                            inch steel sheets.
2.......  CEP-176          Install of two 42-            320           28          472          194       25,119
           Bulkhead.        inch steel pipe
                            piles.
2.......  CEP-176 and CEP- Install of 42-inch            166           15          246          101       15,849
           102.             steel pipe and 24-
                            inch Square precast
                            concrete.
2.......  CEP-176 and CEP- Install of 42-inch            254           23          376          155       18,478
           175.             steel pipe piles
                            and 13-inch
                            polymeric piles.
3.......  Pier 3.........  Install of 24-inch              2          0.1            2            1        2,929
                            Square precast
                            concrete fender
                            piles using two
                            drills.
3.......  CEP-102          Install of 42-inch            507           45          750          308       25,119
           Bulkhead.        steel pipe and 28-
                            inch steel sheets.
4.......  Existing Pier 3  Extraction of 14-             981           87        1,450          596       25,119
           CEP-102          inch timber piles,
           Platform.        install of 42-inch
                            steel pipe and 28-
                            inch steel sheets,
                            and rotary drilling
                            of 24-inch Square
                            precast concrete.
5.......  Existing Pier 3  Concurrent                     77            7          114           47        7,356
           CEP-102          extraction of 16-
           Platform.        and 18-inch Square
                            precast concrete
                            and rotary drilling
                            of 24-inch Square
                            precast concrete.
----------------------------------------------------------------------------------------------------------------

    The maximum distance to the Level A harassment threshold during 
construction would be during the impact driving of 28 inch steel sheets 
at CEP-176 and CEP-102 (1783 m for humpback whale; 63 m for bottlenose 
dolphin; 2123 m for harbor porpoises; and 954 m for pinnipeds). The 
largest calculated Level B harassment isopleth extends out to 25,119 m, 
which would result from concurrent pile driving of the scenarios 
presented in Table 10. While 25,119 m may not be an attainable 
observable distance in all directions, the Level B harassment zone will 
be monitored to the maximum extent possible.

Marine Mammal Occurrence and Take Estimation

    In this section we provide information about the presence, density, 
or group dynamics of marine mammals that will inform the take 
calculations. We describe how the information provided above is brought 
together to produce a quantitative take estimate for each species.
Humpback Whales
    Humpback whales occur in the mouth of the Chesapeake Bay and 
nearshore waters of Virginia during winter and spring months. Several 
satellite tagged humpback whales were detected west of the Chesapeake 
Bay Bridge Tunnel, including two individuals with locations near NAVSTA 
Norfolk and Joint Expeditionary Base Little Creek (Aschettino et al., 
2017). Group size was not reported in these surveys, however most 
whales detected were juveniles. Although two individuals were detected 
in the vicinity of the proposed project activities, there is no 
evidence that they linger for multiple days. Because no density 
estimates are available for the species in this area, the Navy 
estimated one potential sighting of a group of average size (2 
individuals) every 60 days of pile driving. Therefore, given the number 
of project days expected in each year (Table 1), NMFS is proposing to 
authorize a total of 19 takes by Level B harassment of humpback whale 
over the five-year authorization, with no more than seven takes by 
Level B harassment in a given year.
    The largest Level A harassment zone for low-frequency cetaceans 
extends approximately 1783 m from the source during impact pile driving 
of the 28-inch steel sheet piles (Table 8). The Navy plans to shut down 
if a humpback whale is sighted within any of the Level A harassment 
zones for all activities, as indicated in Table 11. Therefore, the Navy 
did not request, and NMFS is not proposing to authorize, take by Level 
A harassment of humpback whales.
Bottlenose Dolphin
    The expected number of bottlenose dolphins in the project area was 
estimated using inshore seasonal

[[Page 14578]]

densities provided in Engelhaupt et al. (2016) from vessel line-
transect surveys near NAVSTA Norfolk and adjacent areas near Virginia 
Beach, Virginia, from August 2012 through August 2015 (Engelhaupt et 
al., 2016). This density includes sightings inshore of the Chesapeake 
Bay from NAVSTA Norfolk west to the Thimble Shoals Bridge, and is the 
most representative density for the project area. To calculate 
potential Level B harassment takes of bottlenose dolphin, NMFS 
conservatively multiplied the density of 1.38 dolphin/km\2\ (from 
Englehaupt et al., 2016) by the largest Level B harassment isopleth for 
each project location (Table 8, 9 and 10), and then by the number of 
days associated with that activity (Table 1). For example, to calculate 
Level B harassment takes associated with work at the existing Pier 3 in 
year 2, NMFS multiplied the density (1.38 dolphins/km\2\) by the 
largest Level B harassment zone for impact pile driving on the 24-inch 
concrete bearing piles at the new Pier 3 (0.043 km\2\) by the 
proportional number of pile driving days for that activity (70 days) 
for a total of 4 Level B harassment takes at Pier 3, for that activity 
in year 1. Takes by Level B harassment were calculated for both 
individual pile driving activities and concurrent pile driving 
activities, as authorized takes are conservatively based on the 
scenario that produces more takes by Level B harassment (Table 11). 
Therefore, NMFS proposes to authorize 28,480 \1\ takes by Level B 
harassment of bottlenose dolphin across all five years, with no more 
than 13,190 takes in a given year.
---------------------------------------------------------------------------

    \1\ Note: This total number of takes by Level B harassment 
proposed for authorization differs from that in the Navy's request 
for Rulemaking. The number presented here conservatively uses 
exposure estimates for concurrent pile driving scenarios in Year 5, 
which were higher than those produced for individual pile driving 
activities.
---------------------------------------------------------------------------

Harbor Porpoise
    Harbor porpoises are known to occur in the coastal waters near 
Virginia Beach (Hayes et al., 2019). Density data for this species 
within the project vicinity do not exist or were not calculated because 
sample sizes were too small to produce reliable estimates of density. 
Harbor porpoise sighting data collected by the U.S. Navy near NAVSTA 
Norfolk and Virginia Beach from 2012 to 2015 (Engelhaupt et al. 2014; 
2015; 2016) did not produce enough sightings to calculate densities. 
One group of two harbor porpoises was seen during spring 2015 
(Engelhaupt et al. 2016). Elsewhere in their range, harbor porpoises 
typically occur in groups of two to three individuals (Carretta et al. 
2001; Smultea et al. 2017).
    Because there are no density estimates for the species in the 
proposed project area, the Navy conservatively estimated one harbor 
porpoise sighting (of two individuals) once every 60 days of pile 
driving or drilling. Therefore, the assumption of two individuals per 
60 days was used for calculation of take numbers. Total pile driving 
days for Year 2 would be 185 days, Year 3 would be 92 days, Year 4 
would be 204 days, and Year 5 would have 32 days. Takes by Level B 
harassment were calculated for both individual pile driving activities 
and concurrent pile driving activities, as authorized takes are 
conservatively based on the scenario that produced the larger exposure 
estimate (Table 11). Using the above methodology, NMFS calculated an 
exposure estimate of 19 incidents of take for harbor porpoises.
    The largest Level A harassment zone for high-frequency cetaceans is 
2,123 m during impact pile driving of the 28-inch steel sheet piles. 
The Navy has proposed to shut down at 500 m for harbor porpoises during 
the aforementioned activity, in addition to shorter distances where 
appropriate for other proposed activities as noted in Table13 as a 
reasonable area to observe for harbor porpoises and implement shutdown 
procedures while avoiding an impracticable number of shutdowns. 
Consequently, the Navy has requested authorization of take by Level A 
harassment for harbor porpoise during the course of the project. Take 
by Level A harassment may not actually occur due to the duration of 
time harbor porpoise would be required to remain within the Level A 
harassment zone to accumulate enough energy to experience PTS. However, 
as a precaution NMFS proposes to authorize a total of 4 takes by Level 
A harassment as requested by the Navy (Table 11) with no more than 2 
takes by Level A harassment occurring in a given year, and 15 total 
takes by Level B harassment with no more than 5 takes by Level B 
harassment occurring in a given year, equaling the aforementioned total 
of 19 takes over 5 years.
Harbor Seal
    The expected number of harbor seals in the project area was 
estimated using systematic land- and vessel-based survey data for in-
water and hauled out seals collected by the U.S. Navy at the CBBT rock 
armor and portal islands from 2014 through 2019 (Jones et al., 2020). 
The average daily seal count from the field season ranged from 8 to 23 
seals, with an average of 13.6 harbor seals across all the field 
seasons.
    The Navy expects, and NMFS concurs, that harbor seals are likely to 
be present from November to April. Consistent with previous nearby 
projects (87 FR 15945; March 31, 2022, 86 FR 24340; May 6, 2021, 86 FR 
17458; April 2, 2021), NMFS calculated take by Level B harassment by 
multiplying 13.6 seals by the number of pile driving days expected to 
occur from November through April (seal season): 74 days in Year 2, 23 
days in Year 3, 133 days in Year 4. And 32 days in Year 5. Potential 
takes by Level A harassment were calculated based on the number of 
production days within seal season on which the Level A harassment 
isopleth exceeds the shutdown zone of 200 m (42 days in Year 2; 3 days 
in Year 3; and 0 days in Year 4 and 5), assuming that approximately 10 
percent of harbor seal exposures would be at or above the Level A 
harassment threshold. Potential takes by Level B harassment were 
calculated by subtracting the Level A harassment takes estimated per 
year from the total calculated takes. Consistent with previous species, 
take estimates are based on the scenario (individual or concurrent) 
that produced the higher take estimate (Table 11). Therefore, the Navy 
is requesting and NMFS is proposing to authorize a total of 4,182 takes 
by Level B harassment and 61 takes by Level A harassment (Table 12).
Gray Seal
    Very little information is available about the occurrence of gray 
seals in the Chesapeake Bay and coastal waters. Although the population 
of the United States may be increasing, there are only a few records 
available at the known haulout sites in Virginia used by gray seals, 
strandings are rare, and they have not been reported in shipboard 
surveys. Assuming that they may utilize the Chesapeake Bay waters, the 
Navy conservatively estimates one gray seal may be exposed to elevated 
noise levels for every 60 days of vibratory pile driving during the six 
month period when they are most likely to be present. Similar to harbor 
seals, the maximum number of pile driving days where gray seals may be 
exposed during seal season per year were used for calculations. The 
scenario (concurrent or individual activities) that produced the larger 
exposure estimate is proposed for authorization (Table 11). Therefore, 
the Navy has requested and NMFS is proposing to authorize 5 takes by 
Level B harassment. Given the low likelihood of encountering gray seals 
during the project and low number of days in

[[Page 14579]]

which Level A harassment isopleths may exceed proposed shutdown zones, 
no take by Level A harassment is proposed for authorization.

Table 11--Calculated Takes by Level A and Level B Harassment for Concurrent and Individual Pile Driving, Removal
                                           and Drilling Scenarios \1\
----------------------------------------------------------------------------------------------------------------
                                                       Individual activities           Concurrent activities
             Year                    Species     ---------------------------------------------------------------
                                                      Level A         Level B         Level A         Level B
----------------------------------------------------------------------------------------------------------------
2.............................  Humpback whale..               0               6               0               2
                                BND--Northern                  0            2691               0            5609
                                 Migratory.
                                BND--Southern
                                 Migratory.
                                BND--NC
                                 Estuarine.
                                Harbor porpoise.               2               4               0               1
                                Harbor seal.....              57             949              25             832
                                Gray seal.......               0               1               0               1
3.............................  Humpback whale..               0               3               0               1
                                BND--Northern                  0            3061               0            1440
                                 Migratory.
                                BND--Southern
                                 Migratory.
                                BND--NC
                                 Estuarine.
                                Harbor porpoise.               0               3               0               1
                                Harbor seal.....               4             309               7             537
                                Gray seal.......               0               0               0               1
4.............................  Humpback whale..               0               7               0               1
                                BND--Northern                  0           13190               0            3023
                                 Migratory.
                                BND--Southern
                                 Migratory.
                                BND--NC
                                 Estuarine.
                                Harbor porpoise.               2               5               0               1
                                Harbor seal.....               0            1809              26             232
                                Gray seal.......               0               2               0               0
5.............................  Humpback whale..               0               2               0               3
                                BND--Northern                  0             383               0            6620
                                 Migratory.
                                BND--Southern
                                 Migratory.
                                BND--NC
                                 Estuarine.
                                Harbor porpoise.               0               1               0               3
                                Harbor seal.....               0             435               0            1115
                                Gray seal.......               0               2               0               1
----------------------------------------------------------------------------------------------------------------
\1\ Potential takes by Level A and Level B harassment are conservatively based on the scenario (individual vs.
  concurrent pile driving, removal, or drilling) that produced the highest exposure estimate. Therefore, the
  number of takes by Level A and Level B harassment proposed for authorization is italicized and used to
  determine percent of stock.


               Table 12--Proposed Authorized Takes by Level A and Level B Harassment by Species and Stock in Comparison to Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                   Proposed take
                   Year                                Species               Abundance   --------------------------------      Total        Percent of
                                                                                              Level A         Level B                          stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
2.........................................  Humpback whale \a\..........            1396               0               6               6            0.43
                                            BND--Northern Migratory \b\             6639               0            5609            2705           40.74
                                             \c\.
                                            BND--Southern Migratory \b\             3751                                            2705           72.10
                                             \c\.
                                            BND--NC Estuarine \b\ \c\...             823                                             200           24.30
                                            Harbor porpoise.............           95543               2               4               6            0.01
                                            Harbor seal.................           61336              57             949            1006            1.64
                                            Gray seal...................           27300               0               1               1            0.00
3.........................................  Humpback whale \a\..........            1396               0               3               3            0.21
                                            BND--Northern Migratory \b\             6639               0            3061            1431           21.55
                                             \c\.
                                            BND--Southern Migratory \b\             3751                                            1431           38.15
                                             \c\.
                                            BND--NC Estuarine \b\ \c\...             823                                             200           24.30
                                            Harbor porpoise.............           95543               0               3               3            0.00
                                            Harbor seal.................           61336               7             537             544            0.89
                                            Gray seal...................           27300               0               1               1            0.00
4.........................................  Humpback whale \a\..........            1396               0               7               7            0.50
                                            BND--Northern Migratory \b\             6639               0           13190            6495           97.83
                                             \c\.
                                            BND--Southern Migratory \b\             3751                                            6495          173.15
                                             \c\.
                                            BND--NC Estuarine \b\ \c\...             823                                             200           24.30
                                            Harbor porpoise.............           95543               2               5               7            0.01
                                            Harbor seal.................           61336              26            1783            1809            2.95
                                            Gray seal...................           27300               0               2               2            0.01
5.........................................  Humpback whale \a\..........            1396               0               3               3            0.21
                                            BND--Northern Migratory \b\             6639               0            6620            3210           48.35
                                             \c\.
                                            BND--Southern Migratory \b\             3751                                            3210           85.58
                                             \c\.
                                            BND--NC Estuarine \b\ \c\...             823                                             200           24.30
                                            Harbor porpoise.............           95543               0               3               3            0.00

[[Page 14580]]

 
                                            Harbor seal.................           61336               0            1115            1115            1.82
                                            Gray seal...................           27300               0               2               2            0.01
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ West Indies DPS. Please see the Description of Marine Mammals in the Area of Specified Activities section for further discussion.
\b\ Take estimates are weighted based on calculated percentages of population for each distinct stock, assuming animals present would follow the same
  probability of presence in the project area. Please see Small Numbers section for additional information.
\c\ Assumes multiple repeated takes of the same individuals from a small portion of each stock as well as repeated takes of Chesapeake Bay resident
  population (size unknown). Please see Small Numbers section for additional information.

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 the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
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, NMFS 
considers two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned), and;
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, and impact on 
operations.
    In addition to the measures described later in this section, the 
Navy will employ the following mitigation measures:
     The Navy will conduct briefings between construction 
supervisors and crews, the marine mammal monitoring team, and Navy 
staff prior to the start of all pile driving activity and when new 
personnel join the work, to explain responsibilities, communication 
procedures, marine mammal monitoring protocol, and operational 
procedures;
     If a marine mammal comes within 10 meters of construction 
activities, including in-water heavy machinery work not being analyzed 
in this proposed rule, operations shall cease and vessels shall reduce 
speed to the minimum level required to maintain steerage and safe 
working conditions;
     Pile driving activity must be halted upon observation of 
either a species for which incidental take is not authorized or a 
species for which incidental take has been authorized but the 
authorized number of takes has been met, entering or is within the 
harassment zone.
    The following mitigation measures apply to the Navy's in-water 
construction activities.
    Establishment of Shutdown Zones--The Navy will establish shutdown 
zones for all pile driving and removal and drilling activities. The 
purpose of a shutdown zone is generally to define an area within which 
shutdown of the activity would occur upon sighting of a marine mammal 
(or in anticipation of an animal entering the defined area). Shutdown 
zones will vary based on the activity type and marine mammal hearing 
group (Table 13).
    Protected Species Observers (PSOs)--The placement of PSOs during 
all pile driving and removal and drilling activities (described in the 
Proposed Monitoring and Reporting section) will ensure that the entire 
shutdown zone is visible. Should environmental conditions deteriorate 
such that the entire shutdown zone would not be visible (e.g., fog, 
heavy rain), pile driving and removal and drilling must be delayed 
until the PSO is confident marine mammals within the shutdown zone 
could be detected.
    Monitoring for Level A and B Harassment--The Navy will monitor the 
Level B harassment zones (areas where SPLs are equal to or exceed the 
160 dB rms threshold for impact pile driving, and the 120 dB rms 
threshold during drilling and vibratory pile driving and removal) and 
Level A harassment zones to the extent practicable, and all of the 
shutdown zones, during all pile driving, removal or drilling days. 
Monitoring zones provide utility for observing by establishing 
monitoring protocols for areas adjacent to the shutdown zones. 
Monitoring zones enable observers to be aware of and communicate the 
presence of marine mammals in the project area outside the shutdown 
zone and thus prepare for a potential cessation of activity should the 
animal enter the shutdown zone.
    Pre-Activity Monitoring--Prior to the start of daily in-water 
construction activity, or whenever a break in pile driving/removal of 
30 minutes or longer occurs, PSOs will observe the shutdown and 
monitoring zones for a period of 30 minutes. The shutdown zone will be 
considered cleared when a marine mammal has not been observed within 
the zone for that 30-minute period. If a marine mammal is observed 
within the shutdown zones listed in Table 13, pile driving and drilling 
activity must be delayed or halted. If pile driving and/or drilling is 
delayed or halted due to the presence of a marine mammal, the activity 
may not commence or resume until either the animal has voluntarily 
exited and been visually confirmed beyond the shutdown zones or 15 
minutes have passed without re-detection of the animal. When a marine 
mammal for which Level B harassment take is authorized is present in 
the Level B harassment zone, activities may begin. If work ceases for 
more than 30 minutes, the pre-activity monitoring of the shutdown zones 
will commence. A determination that the shutdown zone is clear must be 
made during a period of

[[Page 14581]]

good visibility (i.e., the entire shutdown zone and surrounding waters 
must be visible to the naked eye).
    Soft Start--Soft-start procedures are used to provide additional 
protection to marine mammals by providing warning and/or giving marine 
mammals a chance to leave the area prior to the hammer operating at 
full capacity. For impact pile driving, contractors will be required to 
provide an initial set of three strikes from the hammer at reduced 
energy, followed by a 30-second waiting period, then two subsequent 
reduced-energy strike sets. Soft start will be implemented at the start 
of each day's impact pile driving and at any time following cessation 
of impact pile driving for a period of 30 minutes or longer.

                                      Table 13--Proposed Shutdown Zones \1\
----------------------------------------------------------------------------------------------------------------
                                                                                                      Level B
                                                     Shutdown        Shutdown        Shutdown      (behavioral)
                          Pile type, size, and     distance (m)    distance (m)    distance (m)     harassment
       LOA year              driving method        for humpback     for harbor     for all other   distance (m)
                                                      whales         porpoise         species       all marine
                                                                                                      mammals
----------------------------------------------------------------------------------------------------------------
Year 2...............  Impact Install 42-inch              1,490             500             200           1,000
                        steel pipe piles.
                       Vibratory Install 42-inch             140             200              70           2,500
                        steel pipe piles.
                       Impact Install 28-inch              1,790             500             200           2,500
                        steel sheet piles.
                       Vibratory Install 28-inch             110             150              80           2,500
                        steel sheet piles.
                       Impact Install 13-inch                 20              30              30              30
                        polymeric piles.
                       Vibratory Install 13-inch              20              30              30           2,500
                        polymeric piles.
                       Impact Install 24-inch                260             500             200             117
                        precast concrete bearing
                        piles.
                       Impact Install 18-inch                 10              10              10              30
                        precast concrete fender
                        piles.
                       Pre-drilling.............              10              10              10           2,500
Year 3...............  Impact Install 24-inch                 40              50              30             120
                        precast concrete fender
                        piles.
                       Impact Install 18-inch                700             500             200              30
                        steel piles.
                       Impact Install 42-inch              1,010             500             200           1,000
                        steel pipe piles.
                       Vibratory Install 42-inch              90             120              50           2,500
                        steel pipe piles.
                       Impact Install 28-inch              1,790             500             200           2,500
                        steel sheet piles.
                       Vibratory Install 28-inch             110             150              70           2,500
                        steel sheet piles.
                       Vibratory Extract 18-inch              40              60              30           2,500
                        precast concrete fender
                        piles.
                       Pre-drilling.............              10              10              10           2,500
Year 4...............  Impact Install 24-inch                120             150              70             120
                        precast concrete bearing
                        piles.
                       Vibratory Extract 14-inch              70             110              50           2,500
                        timber piles.
                       Impact Install 18-inch                 10              10              10              30
                        precast concrete fender
                        piles.
                       Impact Install 42-inch              1,010             500             200           1,000
                        steel pipe piles.
                       Vibratory Install 42-inch              90             120              50           2,500
                        steel pipe piles.
                       Vibratory Extract 24-inch              50              70              30           2,500
                        concrete fender piles.
                       Impact Install 28-inch              1,790             500             200           2,500
                        steel sheet piles.
                       Vibratory Install 28-inch             120             150              70           2,500
                        steel sheet piles.
                       Vibratory Extract 18-inch              40              60              30           2,500
                        precast concrete fender
                        piles.
                       Vibratory Extract 16- to               40              60              30           2,500
                        18-inch precast concrete
                        bearing piles.
                       Pre-drilling.............              10              10              10           2,500
Year 5...............  Vibratory Extract 16- to               40              60              30           2,500
                        18-inch precast concrete
                        bearing piles.
                       Impact Install 24-inch                120             150              70             120
                        precast concrete bearing
                        piles.
                       Impact Install 18-inch                 10              10              10              30
                        precast concrete fender
                        piles.
                       Pre-drilling.............              10              10              10           2,500
----------------------------------------------------------------------------------------------------------------
\1\ Calculated Level A harassment isopleths for concurrent pile driving were smaller than those calculated for
  individual impact pile driving, vibratory pile driving and removal, and drilling. Therefore, proposed shutdown
  zones conservatively reflect individual activity.

    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means of 
effecting the least practicable impact on the affected species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

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 while 
conducting the activities. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the activity; or (4) biological or 
behavioral

[[Page 14582]]

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.
    The Navy will submit a Marine Mammal Monitoring Plan to NMFS for 
approval in advance of the start of construction.

Visual Monitoring

     Marine mammal monitoring during pile driving and removal 
must be conducted by qualified, NMFS approved PSOs, in accordance with 
the following: PSOs must be independent of the activity contractor (for 
example, employed by a subcontractor) and have no other assigned tasks 
during monitoring periods;
     At least one PSO must have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
     Other PSOs may substitute other relevant experience, 
education (degree in biological science or related field), or training 
for prior experience performing the duties of a PSO during construction 
activity pursuant to a NMFS-issued incidental take authorization;
     PSOs must be approved by NMFS prior to beginning any 
activity subject to this proposed rulemaking; and
     Where a team of three or more PSOs is required, a lead 
observer or monitoring coordinator must be designated. The lead 
observer must have prior experience performing the duties of a PSO 
during construction activity pursuant to a NMFS-issued incidental take 
authorization.
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    The Navy must establish the following monitoring locations and 
visual monitoring of the entire shutdown zones must occur for all pile 
driving and drilling activities. For all pile driving activities, a 
minimum of one PSO must be assigned to the active pile driving or 
drilling location to monitor the shutdown zones and as much of the 
Level A and Level B harassment zones as possible. If the active project 
location includes demolition activities, then the next adjacent pier 
may be used as an appropriate monitoring location ensuring that the 
aforementioned criteria is met. Monitoring must be conducted by a 
minimum of three PSOs for any activity with an associated harassment 
isopleth over 1000 m. All other activities would require a minimum of 
two PSOs. For activities in Table 8, 9 and 10, with Level B harassment 
zones larger than 3000 m, at least one PSO must be stationed on either 
Pier 14 or the North Jetty to monitor the part of the zone exceeding 
the edge of the Norfolk Naval Station (see Figure 3). The third PSO for 
activities whose harassment isopleths exceed 1000 m would be located on 
Pier 1. PSOs will be placed at the best vantage point(s) practicable to 
monitor for marine mammals and implement shutdown/delay procedures (See 
Figure 3 for representative monitoring locations). If changes are 
necessary to ensure full coverage of the proposed shutdown zones, the 
Navy shall contact NMFS to alter observer locations (e.g., vessel 
blocking view from pier locations). Additionally, the shutdown/
monitoring zones may be modified with NMFS' approval following NMFS' 
acceptance of an acoustic monitoring report.
    Monitoring will be conducted 30 minutes before, during, and 30 
minutes after all in water construction activities. In addition, 
observers shall record all incidents of marine mammal occurrence, 
regardless of distance from activity, and shall document any behavioral 
reactions in concert with distance from drilling or piles being driven 
or removed. Pile driving activities include the time to install or 
remove a single pile or series of piles, as long as the time elapsed 
between uses of the pile driving equipment is no more than 30 minutes.
BILLING CODE 3510-22-P

[[Page 14583]]

[GRAPHIC] [TIFF OMITTED] TP09MR23.012

Figure 3. Proposed Protected Species Observer Locations at Naval 
Station Norfolk at Norfolk, Virginia

Acoustic Monitoring

    The Navy plans to implement in situ acoustic monitoring efforts to 
measure SPLs from in-water construction activities for pile types and 
methods that have not been previously collected at NAVSTA Norfolk 
(Table 14). The Navy will collect and evaluate acoustic sound recording 
levels during pile driving activities. Hydrophones would be placed at 
locations 33 ft from the noise source and, where the potential for 
Level A (PTS onset) harassment exists, at a second representative 
monitoring location that is a distance of 20 times the depth of water 
at the pile location. For the pile driving events acoustically 
measured, 100 percent of the data will be analyzed. Please see the 
Navy's Marine Mammal Monitoring Plan and application for additional 
detail.

Table 14--Hydroacoustic Monitoring Summary
[GRAPHIC] [TIFF OMITTED] TP09MR23.013

    \1\ Data has previously been collected on the impact driving of 
24-inch concrete piles and timber piles at NAVSTA Norfolk; 
therefore, no additional data collection is proposed for these pile 
types.
    \2\ Some piles may be either vibratory or pile driving, or a 
combination of both. Pre-drilling may not be utilized if site 
conditions do not require it. The hydroacoustic report at the end of 
construction will clarify which

[[Page 14584]]

installation method was utilized and monitored for each pile type.

BILLING CODE 3510-22-C
    Environmental data shall be collected, including but not limited 
to, the following: Wind speed and direction, air temperature, humidity, 
surface water temperature, water depth, wave height, weather 
conditions, other factors that could contribute to influencing 
underwater sound levels (e.g., aircrafts, boats, etc.).

Reporting

    The Navy is required to submit an annual report on all activities 
and marine mammal monitoring results to NMFS within 90 days following 
the end of each construction year. Additionally, a draft comprehensive 
5-year summary report must be submitted to NMFS within 90 days of the 
end of the project. The annual reports will include an overall 
description of work completed, a narrative regarding marine mammal 
sightings, and associated PSO data sheets. Specifically, the report 
must include:
     Dates and times (begin and end) of all marine mammal 
monitoring
     Construction activities occurring during each daily 
observation period, including: (a) how many and what type of piles were 
driven or removed and the method (i.e., impact or vibratory); and (b) 
the total duration of time for each pile (vibratory driving) or hole 
(drilling) and number of strikes for each pile (impact driving);
     PSO locations during marine mammal monitoring; and
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance.
    Upon observation of a marine mammal the following information must 
be reported:
     Name of PSO who sighted the animal(s) and PSO location and 
activity at the time of sighting;
     Time of sighting;
     Identification of the animal(s) (e.g., genus/species, 
lowest possible taxonomic level, or unidentified), PSO confidence in 
identification, and the composition of the group if there is a mix of 
species;
     Distance and location of each observed marine mammal 
relative to the pile being driven or hole being drilled for each 
sighting;
     Estimated number of animals (min/max/best estimate);
     Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, etc.);
     Description of any marine mammal behavioral observations 
(e.g., no response or changes in behavioral state such as ceasing 
feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones, by species; and
     Detailed information about implementation of any 
mitigation (e.g., shutdowns and delays), a description of specified 
actions that ensured, and resulting changes in behavior of the 
animal(s), if any.
    The acoustic monitoring report must contain the informational 
elements described in the Marine Mammal Monitoring Plan and, at 
minimum, must include:
     Hydrophone equipment and methods: Recording device, 
sampling rate, distance (m) from the pile where recordings were made; 
depth of water and recording device(s);
     Type and size of pile being driven, substrate type, method 
of driving during recordings (e.g., hammer model and energy), and total 
pile driving duration;
     Whether a sound attenuation device is used and, if so, a 
detailed description of the device used and the duration of its use per 
pile;
     For impact pile driving and/or drilling (per pile): Number 
of strikes and strike rate; depth of substrate to penetrate; pulse 
duration and mean, median, and maximum sound levels (dB re: 1 
[micro]Pa): Root mean square sound pressure level (SPLrms); 
cumulative sound exposure level (SELcum), peak sound 
pressure level (SPLpeak), and single-strike sound exposure 
level (SELs-s); and
     For vibratory driving/removal and/or drilling (per pile): 
Duration of driving per pile; mean, median, and maximum sound levels 
(dB re: 1 [micro]Pa): Root mean square sound pressure level 
(SPLrms), cumulative sound exposure level 
(SELcum) (and timeframe over which the sound is averaged).
    If no comments are received from NMFS within 30 days, the draft 
reports will constitute the final reports. If comments are received, a 
final report addressing NMFS' comments must be submitted within 30 days 
after receipt of comments. All PSO datasheets and/or raw sighting data 
must be submitted with the draft marine mammal report.

Reporting of Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the Navy shall report the 
incident to NMFS Office of Protected Resources (OPR) 
([email protected]), NMFS (301-427-8401) and to the 
Greater Atlantic Region New England/Mid-Atlantic Stranding Coordinator 
(866-755-6622) as soon as feasible. The report must include the 
following information:
    [ssquf] Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    [ssquf] Species identification (if known) or description of the 
animal(s) involved;
    [ssquf] Condition of the animal(s) (including carcass condition if 
the animal is dead);
    [ssquf] Observed behaviors of the animal(s), if alive;
    [ssquf] If available, photographs or video footage of the 
animal(s); and
    [ssquf] General circumstances under which the animal was 
discovered.
    If the death or injury was clearly caused by the specified 
activity, the Navy must immediately cease the specified activities 
until NMFS OPR is able to review the circumstances of the incident and 
determine what, if any, additional measures are appropriate to ensure 
compliance with the terms of this proposed rule. The Navy shall not 
resume their activities until notified by NMFS that they can continue.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any impacts or responses (e.g., intensity, duration), 
the context of any impacts or responses (e.g., critical reproductive 
time or location, foraging impacts affecting energetics), 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' implementing

[[Page 14585]]

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 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 the species listed in Table 3, given that many of the 
anticipated effects of this project on different marine mammal stocks 
are expected to be relatively similar in nature. Where there are 
meaningful differences between species or stocks, or groups of species, 
in anticipated individual responses to activities, impact of expected 
take on the population due to differences in population status, or 
impacts on habitat, they are described independently in the analysis 
below.
    Construction activities associated with the project, as outlined 
previously, have the potential to disturb or displace marine mammals. 
Specifically, the specified activities may result in take, in the form 
of Level A and Level B harassment from underwater sounds generated by 
pile driving activities, pile removal, and drilling. Potential takes 
could occur if marine mammals are present in zones ensonified above the 
thresholds for Level A and Level B harassment, identified above, while 
activities are underway.
    The Level A harassment zones identified in Tables 6 and 7 are based 
upon an animal exposed to pile driving or drilling multiple piles per 
day. Considering the short duration to impact drive each pile and 
breaks between pile installations (to reset equipment and move pile 
into place), an animal would have to remain within the area estimated 
to be ensonified above the Level A harassment threshold for multiple 
hours. This is highly unlikely given marine mammal movement throughout 
the area, especially for small, fast moving species such as small 
cetaceans and pinnipeds. Additionally, no Level A harassment is 
anticipated for humpback whales due to the required mitigation 
measures, which we expect the Navy will be able to effectively 
implement given the majority of the Level A harassment zones are small 
(under 300 m except for a few activities where additional PSOs will be 
utilized to cover the entirety of the Level A harassment zone), and 
high visibility of humpback whales. If an animal was exposed to 
sufficient accumulated sound energy to incur PTS, the resulting PTS 
would likely be small (e.g., PTS onset) at lower frequencies where pile 
driving energy is concentrated, and unlikely to result in impacts to 
individual fitness, reproduction, or survival.
    The nature of activities included in the Navy's pile driving 
project precludes the likelihood of serious injury or mortality. For 
all species and stocks, take will occur within a limited, confined area 
(immediately surrounding NAVSTA Norfolk in the Chesapeake Bay area) of 
the stock's range. Level A and Level B harassment will be reduced to 
the level of least practicable adverse impact through use of mitigation 
measures described herein. Furthermore, the amount of take authorized 
is extremely small when compared to stock abundance for all species 
aside from bottlenose dolphins, however take authorized for bottlenose 
dolphins is still expected to be small relative to the stock abundance 
as described in the Small Numbers section.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from other 
similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring) (e.g., Thorson and Reyff 
2006). Individual animals, even if taken multiple times, will most 
likely move away from the sound source and be temporarily displaced 
from the areas of pile driving or drilling, although even this reaction 
has been observed primarily only in association with impact pile 
driving. The pile driving and drilling activities analyzed here are 
similar to, or less impactful than, numerous other construction 
activities conducted along both Atlantic and Pacific coasts, which have 
taken place with no known long-term adverse consequences from 
behavioral harassment. Furthermore, many projects similar to this one 
are also believed to result in multiple takes of individual animals 
without any documented long-term adverse effects. Level B harassment 
will be minimized through use of mitigation measures described herein 
and, if sound produced by project activities is sufficiently 
disturbing, animals are likely to simply avoid the area while the 
activity is occurring, particularly as the project is located on a busy 
waterfront with high amounts of vessel traffic.
    UMEs have been declared for Northeast pinnipeds (including harbor 
seal and gray seal) and Atlantic humpback whale. However, we do not 
expect authorized takes to exacerbate or compound upon these ongoing 
UMEs. As noted previously, no injury, serious injury, or mortality is 
expected or authorized, and Level B harassment takes of humpback whale, 
harbor seal and gray seal will be reduced to the level of least 
practicable adverse impact through the incorporation of the mitigation 
measures. For the WNA stock of gray seal, the estimated stock abundance 
is 27,300 (424,300 including estimates in Canadian waters). Given that 
only 1-2 takes by Level B harassment are authorized for this stock 
annually, we do not expect this authorization to exacerbate or compound 
upon the ongoing UME.
    For the WNA stock of harbor seals, the estimated abundance is 
61,336 individuals. The estimated M/SI (339) is well below the PBR 
(1,729). As such, the Level B harassment takes of harbor seal are not 
expected to exacerbate or compound upon the ongoing UMEs.
    With regard to humpback whales, the UME does not yet provide cause 
for concern regarding population-level impacts. Despite the UME, the 
relevant population of humpback whales (the West Indies breeding 
population, or distinct population segment (DPS)) remains healthy.
    Prior to 2016, humpback whales were listed under the ESA as an 
endangered species worldwide. Following a 2015 global status review 
(Bettridge et al., 2015), NMFS established 14 DPSs with different 
listing statuses (81 FR 62259; September 8, 2016) pursuant to the ESA. 
The West Indies DPS, which consists of the whales whose breeding range 
includes the Atlantic margin of the Antilles from Cuba to northern 
Venezuela, and whose feeding range primarily includes the Gulf of 
Maine, eastern Canada, and western Greenland, was delisted. The status 
review identified harmful algal blooms, vessel collisions, and fishing 
gear entanglements as relevant threats for this DPS, but noted that all 
other threats are considered likely to have no or minor impact on 
population size or the growth rate of this DPS (Bettridge et al., 
2015). As described in Bettridge et al. (2015), the West Indies DPS has 
a substantial population size (i.e., 12,312 (95 percent CI 8,688-
15,954) whales in 2004-2005 (Bettridge et al., 2003)), and appears to 
be experiencing consistent growth. NMFS is proposing to authorize no 
more than eight takes by Level B harassment annually of humpback whale.
    The project is also not expected to have significant adverse 
effects on affected marine mammals' habitats. The project activities 
will not modify existing marine mammal habitat for a significant amount 
of time. The

[[Page 14586]]

activities may cause some fish to leave the area of disturbance, thus 
temporarily impacting marine mammals' foraging opportunities in a 
limited portion of the foraging range; but, because of the short 
duration of the activities and the relatively small area of the habitat 
that may be affected (with no known particular importance to marine 
mammals), the impacts to marine mammal habitat are not expected to 
cause significant or long-term negative consequences.
    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 any of the species 
or stocks through effects on annual rates of recruitment or survival:
     No mortality is anticipated or authorized;
     Authorized Level A harassment would be very small amounts 
and of low degree;
     The intensity of anticipated takes by Level B harassment 
is relatively low for all stocks;
     The number of anticipated takes is very low for humpback 
whale, harbor porpoise, and gray seal;
     The specified activity and associated ensonified areas are 
very small relative to the overall habitat ranges of all species and do 
not include habitat areas of special significance;
     The lack of anticipated significant or long-term negative 
effects to marine habitat;
     The presumed efficacy of the mitigation measures in 
reducing the effects of the specified activity;
     Monitoring reports from similar work in the Chesapeake Bay 
have documented little to no effect on individuals of the same species 
impacted by similar activities.
    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 previously, only small numbers of incidental take may be 
authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. When the predicted number of 
individuals to be taken is fewer than one-third of the species or stock 
abundance, the take is considered to be of small numbers. Additionally, 
other qualitative factors may be considered in the analysis, such as 
the temporal or spatial scale of the activities.
    The maximum annual take of take NMFS proposes to authorize for the 
five marine mammal stocks is below one-third of the estimated stock 
abundance for all species except for the WNA southern coastal migratory 
stock and the WNA northern coastal migratory stock of bottlenose 
dolphins (see Table 12).
    There are three bottlenose dolphin stocks that could occur in the 
project area. Therefore, largest estimated annual take by Level B 
harassment of 13,190 bottlenose dolphin would likely be split among the 
western WNA northern coastal migratory stock, the WNA southern coastal 
migratory stock, and the northern North Carolina Estuarine stock 
(NNCES). Based on the stocks' respective occurrence in the area, NMFS 
estimates that there would be no more than 200 takes from the NNCES 
stock, representing 24 percent of that population, with the remaining 
takes split evenly between the northern and southern coastal migratory 
stocks. Based on the consideration of various factors as described 
below, we have preliminarily determined that the number of individuals 
taken will comprise of less than one-third of the best available 
population abundance estimate of either coastal migratory stock. 
Detailed descriptions of the stocks' ranges have been provided in the 
Description of Marine Mammals in the Area of Specified Activities 
section.
    Both the northern migratory coastal and southern migratory coastal 
stocks have expensive ranges and they are the only dolphin stocks 
thought to make broad scale, seasonal migrations in coastal waters of 
the western North Atlantic. Given the large ranges associated with 
these two stocks, it is unlikely that large segments of either stock 
would approach the project area and enter into the Chesapeake Bay. The 
majority of both stocks are likely to be found widely dispersed across 
their respective habitat ranges and unlikely to be concentrated in or 
near the Chesapeake Bay.
    Furthermore, the Chesapeake Bay and nearby offshore waters 
represent the boundaries of the ranges of each of the two coastal 
stocks during migration. The northern migratory coastal stock is found 
during warm water months from coastal Virginia, including the 
Chesapeake Bay and Long Island, New York. The stock migrates south in 
late summer and fall. During cold water months, dolphins may be found 
in coastal waters from Cape Lookout, North Carolina, to the North 
Carolina/Virginia border. During January-March, the southern Migratory 
coastal stock appears to move as far south as northern Florida. From 
April-June, the stock moves back north to North Carolina. During the 
warm water months of July-August, the stock is presumed to occupy the 
coastal waters north of Cape Lookout, North Carolina, to Assateague, 
Virginia, including the Chesapeake Bay. There is likely some overlap 
between the northern southern migratory stocks during spring and fall 
migrations, but the extent of overlap is unknown.
    The Chesapeake Bay and waters offshore of the mouth are located on 
the periphery of the migratory ranges of both coastal stocks (although 
during different seasons). Additionally, each of the migratory coastal 
stocks are likely to be located in the vicinity of the Bay for 
relatively short timeframes. Given the limited number of animals from 
each migratory coastal stock likely to be found at the seasonal 
migratory boundaries of their respective ranges, in combination with 
the short time periods (~2 months) animals might remain at these 
boundaries, it is reasonable to assume that takes are likely to occur 
only within some small portion of either of the migratory coastal 
stocks.
    Many of the dolphin observations in the Bay are likely repeated 
sightings of the same individuals. The Potomac-Chesapeake Dolphin 
Project has observed over 1,200 unique animals since observations began 
in 2015. Re-sightings of the same individual can be highly variable. 
Some dolphins are observed once per year, while others are highly 
regular with greater than 10 sightings per year (Mann, Personal 
Communication). Similarly, using available photo-identification data, 
Engelhaupt et al. (2016) determined that specified individuals were 
often observed in close proximity to their original sighting locations 
and were observed multiple times in the same season or same year. 
Ninety-one percent of re-sighted individuals (100 of 110) in the study 
area were recorded less than 30 kilometers from the initial sighting 
location. Multiple sightings of the same individual would considerably 
reduce the number of individual animals that are taken by harassment. 
Furthermore, the existence of a resident dolphin

[[Page 14587]]

population in the Bay would increase the percentage of dolphin takes 
that are actually re-sightings of the same individuals.
    In summary and as described above, the following factors primarily 
support our determination regarding the incidental take of small 
numbers of the affected stocks of a species or stock:
     The take of marine mammal stocks proposed for 
authorization comprises less than 3 percent of any stock abundance 
(with the exception of the three bottlenose dolphin stocks);
     Potential bottlenose dolphin takes in the project area are 
likely to be allocated among three distinct stocks;
     Bottlenose dolphin stocks in the project area have 
extensive ranges and it would be unlikely to find a high percentage of 
the individuals of any one stock concentrated in a relatively small 
area such as the project area or the Chesapeake Bay;
     The Chesapeake Bay represents the migratory boundary for 
each of the specified dolphin stocks and it would be unlikely to find a 
high percentage of any stock concentrated at such boundaries; and
     Many of the takes would likely be repeats of the same 
animals and likely from a resident population of the Chesapeake Bay.
    Based on the analysis contained herein of the activity (including 
the 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 stock.

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.

Adaptive Management

    The regulations governing the take of marine mammals incidental to 
Navy construction activities would contain an adaptive management 
component. The reporting requirements associated with this proposed 
rule are designed to provide NMFS with monitoring data from completed 
projects to allow consideration of whether any changes are appropriate. 
The use of adaptive management allows NMFS to consider new information 
from different sources to determine (with input from the Navy regarding 
practicability) on an annual or biennial basis if mitigation or 
monitoring measures should be modified (including additions or 
deletions). Mitigation measures could be modified if new data suggests 
that such modifications would have a reasonable likelihood of reducing 
adverse effects to marine mammals and if the measures are practicable.
    The following are some of the possible sources of applicable data 
to be considered through the adaptive management process: (1) Results 
from monitoring reports, as required by MMPA authorizations; (2) 
results from general marine mammal and sound research; and (3) any 
information which reveals that marine mammals may have been taken in a 
manner, extent, or number not authorized by these regulations or 
subsequent LOAs.

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure ESA compliance for the issuance of IHAs, 
NMFS consults internally whenever we propose to authorize take for 
endangered or threatened species.
    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.

Request for Information

    NMFS requests that interested persons submit comments, information, 
and suggestions concerning the Navy's request and the proposed 
regulations (see ADDRESSES). All comments will be reviewed and 
evaluated as we prepare a final rule and make final determinations on 
whether to issue the requested authorization. This proposed rule and 
supporting documents provide all environmental information relating to 
our proposed action for public review.

Classification

    Pursuant to the procedures established to implement Executive Order 
12866, the Office of Management and Budget has determined that this 
proposed rule is not significant.
    Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA), 
the Chief Counsel for Regulation of the Department of Commerce has 
certified to the Chief Counsel for Advocacy of the Small Business 
Administration that this proposed rule, if adopted, would not have 
significant economic impact on a substantial number of small entities. 
The U.S. Navy is the sole entity that would be subject to the 
requirements in these proposed regulations, and the Navy is not a small 
governmental jurisdiction, small organization, or small business, as 
defined by the RFA. Because of this certification, a regulatory 
flexibility analysis in not required and none has been prepared.
    This proposed rule does not contain a collection-of-information 
requirement subject to the provisions of the Paperwork Reduction Act 
(PRA) because the applicant is a Federal agency.

List of Subjects in 50 CFR Part 217

    Acoustics, Administrative practice and procedure, Construction, 
Endangered and threatened species, Marine mammals, Mitigation and 
Monitoring requirements, Reporting requirements, Wildlife.

    Dated: March 2, 2023.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, NOAA proposes to amend 50 
CFR part 217 as follows:

PART 217--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE 
MAMMALS

0
1. The authority citation for part 217 continues to read as follows:

    Authority: 16 U.S.C. 1361 et seq., unless otherwise noted.

0
2. Revise subpart L to read as follows:

Subpart L--Taking and Importing Marine Mammals Incidental to Navy 
Construction of the Pier 3 Replacement Project at Naval Station 
Norfolk at Norfolk, Virginia

Sec.
217.110 Specified activity and geographical region.
217.111 Effective dates.
217.112 Permissible methods of taking.
217.113 Prohibitions.
217.114 Mitigation requirements.
217.115 Requirements for monitoring and reporting.
217.116 Letters of Authorization.
217.117 Renewals and modifications of Letters of Authorization.
217.118 [Reserved]
217.119 [Reserved]

[[Page 14588]]

Sec.  217.110  Specified activity and geographical region.

    (a) Regulations in this subpart apply only to the U.S. Navy (Navy) 
and those persons it authorizes or funds to conduct activities on its 
behalf for the taking of marine mammals that occurs in the areas 
outlined in paragraph (b) of this section and that occurs incidental to 
construction activities related to the replacement of Pier 3 at Naval 
Station Norfolk at Norfolk, Virginia.
    (b) The taking of marine mammals by the Navy may be authorized in a 
Letter of Authorization (LOA) only if it occurs at Naval Station 
Norfolk, Norfolk, Virginia.


Sec.  217.111  Effective dates.

    Regulations in this subpart are effective for a period of five 
years from the date of issuance.


Sec.  217.112  Permissible methods of taking.

    Under an LOA issued pursuant to Sec. Sec.  216.106 of this chapter 
and 217.116, the Holder of the LOA (hereinafter ``Navy'') may 
incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  217.110(b) by harassment associated with 
construction activities related to replacement of Pier 3, provided the 
activity is in compliance with all terms, conditions, and requirements 
of the regulations in this subpart and the applicable LOA.


Sec.  217.113  Prohibitions.

    (a) Except for the takings contemplated in Sec.  217.112 and 
authorized by a LOA issued under Sec. Sec.  216.106 of this chapter and 
217.116, it is unlawful for any person to do any of the following in 
connection with the activities described in Sec.  217.110:
    (1) Violate, or fail to comply with, the terms, conditions, and 
requirements of this subpart or a LOA issued under Sec. Sec.  216.106 
of this chapter and 217.116;
    (2) Take any marine mammal not specified in such LOA;
    (3) Take any marine mammal specified in such LOA in any manner 
other than as specified;
    (4) Take a marine mammal specified in such LOA after NMFS 
determines such taking results in more than a negligible impact on the 
species or stocks of such marine mammal; or
    (5) Take a marine mammal specified in such LOA after NMFS 
determined such taking results in an unmitigable adverse impact on the 
species or stock of such marine mammal for taking for subsistence uses.
    (b) [Reserved].


Sec.  217.114  Mitigation requirements.

    (a) When conducting the activities identified in Sec.  217.110(a), 
the mitigation measures contained in this subpart and any LOA issued 
under Sec. Sec.  216.106 of this chapter and 217.116 must be 
implemented by the Navy. These mitigation measures include:
    (1) A copy of any issued LOA must be in the possession of the Navy, 
supervisory construction personnel, lead protected species observers 
(PSOs), and any other relevant designees of the Navy operating under 
the authority of the LOA at all times that activities subject to the 
LOA are being conducted;
    (2) The Navy must ensure that construction supervisors and crews, 
the monitoring team, and relevant Navy staff are trained prior to the 
start of activities subject to any issued LOA, so that 
responsibilities, communication procedures, monitoring protocols, and 
operational procedures are clearly understood. New personnel joining 
during the project must be trained prior to commencing work;
    (3) The Navy, construction supervisors and crews, and relevant Navy 
staff must avoid direct physical interaction with marine mammals during 
construction activity. If a marine mammal comes within 10 m of such 
activity, operations must cease and vessels must reduce speed to the 
minimum level required to maintain steerage and safe working 
conditions, as necessary to avoid direct physical interaction;
    (4) The Navy must employ PSOs and establish monitoring locations as 
described in the NMFS-approved Marine Mammal Monitoring Plan. The Navy 
must monitor the project area to the maximum extent possible based on 
the required number of PSOs, required monitoring locations, and 
environmental conditions;
    (5) For all pile driving and drilling activity, the Navy shall 
implement shutdown zones with radial distances as identified in a LOA 
issued under Sec.  217.116. If a marine mammal is observed entering or 
within the shutdown zone, such operations must be delayed or halted.
    (6) Monitoring must take place from 30 minutes prior to initiation 
of pile driving or drilling activity (i.e., pre-start clearance 
monitoring) through 30 minutes post-completion of pile driving or 
drilling activity.
    (7) Pre-start clearance monitoring must be conducted during periods 
of visibility sufficient for the lead PSO to determine that the 
shutdown zones are clear of marine mammals. Pile driving and drilling 
may commence following 30 minutes of observation when the determination 
is made that the shutdown zones are clear of marine mammals
    (8) If pile driving and/or drilling is delayed or halted due to the 
presence of a marine mammal, the activity may not commence or resume 
until either the animal has voluntarily exited and been visually 
confirmed beyond the shutdown zone or 15 minutes have passed without 
re-detection of the animal.
    (9) Pile driving activity must be halted upon observation of either 
a species for which incidental take is not authorized or a species for 
which incidental take has been authorized but the authorized number of 
takes has been met, entering or within the harassment zone.
    (10) The Navy must use soft start techniques when impact pile 
driving. Soft start requires contractors to provide an initial set of 
strikes at reduced energy, followed by a 30-second waiting period, then 
two subsequent reduced-energy strike sets. A soft start must be 
implemented at the start of each day's impact pile driving and at any 
time following cessation of impact pile driving for a period of 30 
minutes or longer.
    (b) [Reserved]


Sec.  217.115  Requirements for monitoring and reporting.

    (a) The Navy shall submit a Marine Mammal Monitoring Plan to NMFS 
for approval in advance of construction. Marine mammal monitoring must 
be conducted in accordance with the conditions in this section and the 
NMFS-approved Marine Mammal Monitoring Plan.
    (b) Monitoring must be conducted by qualified, NMFS-approved PSOs, 
in accordance with the following conditions:
    (1) PSOs must be independent of the activity contractor (for 
example, employed by a subcontractor) and have no other assigned tasks 
during monitoring periods;
    (2) At least one PSO must have prior experience performing the 
duties of an observer during construction activity pursuant to a NMFS-
issued incidental take authorization;
    (3) Other observers may substitute other relevant experience, 
education (degree in biological science or related field), or training 
for prior experience performing the duties of an observer during 
construction activity pursuant to a NMFS-issued incidental take 
authorization;
    (4) One observer must be designated as lead observer or monitoring 
coordinator. The lead observer must have prior experience performing 
the

[[Page 14589]]

duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization;
    (5) Observers must be approved by NMFS prior to beginning any 
activity subject to any issued LOA;
    (6) For all pile driving activities, a minimum of two observers 
shall be stationed at the best vantage points practicable to monitor 
for marine mammals and implement shutdown/delay procedures;
    (7) For all pile driving activities, a minimum of two observers 
shall be stationed at the active pile driving site, docks, or piers to 
monitor the harassment and shutdown zones, and as described in the 
Marine Mammal Monitoring Plan. For shutdown zones exceeding 1000 
meters, a minimum of three observers shall be stationed appropriately, 
as described in the Marine Mammal Monitoring Plan, to monitor the 
entire shutdown zone.
    (8) The Navy shall monitor the harassment zones to the extent 
practicable and the entire shutdown zones. The Navy shall monitor at 
least a portion of the Level B harassment zone on all pile driving 
days.
    (9) The Navy shall conduct hydroacoustic data collection in 
accordance with a Marine Mammal Monitoring Plan that must be approved 
by NMFS in advance of construction.
    (10) The shutdown/monitoring zones may be modified with NMFS' 
approval following NMFS' acceptance of an acoustic monitoring report.
    (11) The Navy must submit a draft monitoring report to NMFS within 
90 calendar days of the completion of each construction year. A draft 
comprehensive 5-year summary report must also be submitted to NMFS 
within 90 days of the end of the project. The reports must detail the 
monitoring protocol and summarize the data recorded during monitoring. 
Final annual reports and the final comprehensive report must be 
prepared and submitted within 30 days following resolution of any NMFS 
comments on the draft report. If no comments are received from NMFS 
within 30 days of receipt of the draft report, the report must be 
considered final. If comments are received, a final report addressing 
NMFS comments must be submitted within 30 days after receipt of 
comments. The reports must at minimum contain the informational 
elements described below (as well as any additional information 
described in the Marine Mammal Monitoring Plan), including:
    (i) Dates and times (begin and end) of all marine mammal 
monitoring;
    (ii) Construction activities occurring during each daily 
observation period, including the number and type of piles that were 
driven or removed and by what method (i.e., impact, vibratory or 
drilling), total duration of driving time for each pile (vibratory and 
drilling) and number of strikes for each pile (impact);
    (iii) PSO locations during marine mammal monitoring;
    (iv) Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
    (v) Upon observation of a marine mammal, the follow information:
    (A) Name of PSO who sighted the animal(s) and PSO location and 
activity at time of sighting;
    (B) Time of sighting;
    (C) Identification of the animal(s) (e.g., genus/species, lowest 
possible taxonomic level, or unidentified), PSO confidence in 
identification, and the composition of the group if there is a mix of 
species;
    (D) Distance and location of each observed marine mammal relative 
to the pile being driven for each sighting;
    (E) Estimated number of animals (min/max/best estimate);
    (F) Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, etc.);
    (G) Animal's closest point of approach and estimated time spent 
within the harassment zone;
    (vi) Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted form the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
    (vii) Number of marine mammals detected within the harassment 
zones, by species; and
    (viii) Detailed information about implementation of any mitigation 
(e.g., shutdown and delays), a description of specific actions that 
ensued, and resulting changes in behavior of the animal(s), if any.
    (12) The Holder must submit all PSO datasheets and/or raw sighting 
data within the draft report.
    (13) All draft and final monitoring reports must be submitted to 
[email protected] and [email protected].
    (14) The Navy must report hydroacoustic data collected as required 
by a LOA issued under Sec. Sec.  216.106 of this chapter and 217.116 
and as discussed in the Navy's Marine Mammal Monitoring Plan approved 
by NMFS.
    (15) In the event that personnel involved in the construction 
activities discover an injured or dead marine mammal, the Navy shall 
report the incident to the Office of Protected Resources (OPR), NMFS 
and to the Greater Atlantic Region New England/Mid-Atlantic Regional 
Stranding Coordinator as soon as feasible. If the death or injury was 
clearly caused by the specified activity, the Navy must immediately 
cease the specified activities until NMFS is able to review the 
circumstances of the incident and determine what, if any, additional 
measures are appropriate to ensure compliance with the terms of the 
authorization. The Navy must not resume their activities until notified 
by NMFS. The report must include the following information:
    (i) Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    (ii) Species identification (if known) or description of the 
animal(s) involved;
    (iii) Condition of the animal(s) (including carcass condition if 
the animal is dead);
    (iv) Observed behaviors of the animal(s), if alive;
    (v) If available, photographs or video footage of the animal(s); 
and
    (vi) General circumstances under which the animal was discovered.


Sec.  217.116  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to these 
regulations, the Navy must apply for and obtain an LOA.
    (b) An LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of these regulations.
    (c) If an LOA expires prior to the expiration date of these 
regulations, the Navy may apply for and obtain a renewal of the LOA.
    (d) In the event of projected changes to the activity or to 
mitigation and monitoring measures required by an LOA, the Navy must 
apply for and obtain a modification of the LOA as described in Sec.  
217.116.
    (e) The LOA must set forth the following information:
    (1) Permissible methods of incidental taking;
    (2) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species, its habitat, and on the availability of the 
species for subsistence uses; and

[[Page 14590]]

    (3) Requirements for monitoring and reporting.
    (f) Issuance of the LOA must be based on a determination that the 
level of taking must be consistent with the findings made for the total 
taking allowable under these regulations.
    (g) Notice of issuance or denial of an LOA must be published in the 
Federal Register within 30 days of a determination.


Sec.  217.117  Renewals and modifications of Letters of Authorization.

    (a) An LOA issued under Sec. Sec.  216.106 of this chapter and 
217.116 for the activity identified in Sec.  217.110(a) may be renewed 
or modified upon request by the applicant, provided that:
    (1) The proposed specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for these regulations; and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOA under these regulations were 
implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation, monitoring, or 
reporting that do not change the findings made for the regulations or 
result in no more than a minor change in the total estimated number of 
takes (or distribution by species or years), NMFS may publish a notice 
of proposed LOA in the Federal Register, including the associated 
analysis of the change, and solicit public comment before issuing the 
LOA.
    (c) A LOA issued under Sec. Sec.  216.106 of this chapter and 
217.116 for the activity identified in Sec.  217.110(a) may be modified 
by NMFS under the following circumstances:
    (1) NMFS may modify (including augment) the existing mitigation, 
monitoring, or reporting measures (after consulting with Navy regarding 
the practicability of the modifications) if doing so creates a 
reasonable likelihood of more effectively accomplishing the goals of 
the mitigation and monitoring set forth in the preamble for these 
regulations;
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in a LOA:
    (A) Results from Navy's monitoring from previous years;
    (B) Results from other marine mammal and/or sound research or 
studies; and
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent or number not authorized by these regulations or 
subsequent LOAs; and
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
must publish a notice of proposed LOA in the Federal Register and 
solicit public comment;
    (2) If NMFS determines that an emergency exists that poses a 
significant risk to the well-being of the species or stocks of marine 
mammals specified in a LOA issued pursuant to Sec. Sec.  216.106 of 
this chapter and 217.116, a LOA may be modified without prior notice or 
opportunity for public comment. Notification would be published in the 
Federal Register within 30 days of the action.


Sec. Sec.  217.118-217.119  [Reserved]

[FR Doc. 2023-04613 Filed 3-8-23; 8:45 am]
BILLING CODE 3510-22-P