[Federal Register Volume 88, Number 96 (Thursday, May 18, 2023)]
[Rules and Regulations]
[Pages 31633-31657]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-10168]



[[Page 31633]]

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 230508-0126]
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: Final rule; notification of issuance of Letter of 
Authorization.

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SUMMARY: NMFS, upon request from the U.S. Navy (Navy), hereby issues 
regulations to govern the unintentional taking of marine mammals 
incidental to construction activities associated with the replacement 
of Pier 3 at Naval Station (NAVSTA) Norfolk in Norfolk, Virginia over 
the course of 5 years (2023-2028). These regulations, which allow for 
the issuance of a Letter of Authorization (LOA) for the incidental take 
of marine mammals during the described activities and specified 
timeframes, prescribe the permissible methods of taking and other means 
of effecting the least practicable adverse impact on marine mammal 
species or stocks and their habitat, as well as requirements pertaining 
to the monitoring and reporting of such taking.

DATES: This rule is effective from May 18, 2023, through May 18, 2028.

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.

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

SUPPLEMENTARY INFORMATION:

Purpose and Need for Regulatory Action

    We received an application from the Navy requesting 5-year 
regulations and authorization to take multiple species of marine 
mammals. This rule establishes a framework under the authority of the 
Marine Mammal Protection Act (MMPA) (16 U.S.C. 1361 et seq.) to allow 
for the authorization of take by Level A and Level B harassment of 
marine mammals incidental to the Navy's construction activities related 
to the replacement of Pier 3 at Naval Station Norfolk in Norfolk, 
Virginia. Please see Background below for definitions of harassment.

Legal Authority for the 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 5 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 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 rule containing 5-year 
regulations, and for any subsequent LOAs. As directed by this legal 
authority, this rule contains mitigation, monitoring, and reporting 
requirements.

Summary of Major Provisions Within the Rule

    Following is a summary of the major provisions of this 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; and
     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 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.

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 in the Federal Register for public 
review and comment on October 7, 2022 (87 FR 60998). We did not receive 
substantive comments on the notice of receipt (NOR).
    On March 9, 2023, NMFS published a notice of proposed rulemaking in 
the Federal Register (88 FR 14560). The regulations are valid for 5 
years (2023-2028) from the date of issuance, and authorize the Navy to 
take five species of marine mammals by Level B harassment and, for a 
subset of these species, Level A harassment incidental to construction 
activities related to the replacement of Pier 3 at Naval Station 
Norfolk, Norfolk, Virginia. Neither the Navy nor NMFS expect serious 
injury or mortality to marine mammals to result from this activity, and 
none has been authorized.

[[Page 31634]]

    NMFS previously issued an Incidental Harassment Authorization (IHA) 
(87 FR 15945, March 21, 2022) to the Navy for authorization to take 
marine mammals during the first year of the construction project 
described in this rule. Upon request from the Navy, NMFS modified the 
2022 IHA (88 FR 2880, January 18, 2023) to include concurrent pile 
driving and drilling activities due to a change in the contractor's 
construction plan that was not initially analyzed in the initial 
activity. This rule could not be completed prior to expiration of the 
Navy's modified 2022 IHA and, therefore, the Navy requested issuance of 
a renewal IHA associated with continued work towards completion of year 
1 of the construction project. The requested renewal IHA was issued on 
March 30, 2023 (88 FR 20133, April 5, 2023). As required, the Navy 
provided monitoring reports (available at: https://www.fisheries.noaa.gov/action/incidental-take-authorization-replacement-pier-3-naval-station-norfolk-norfolk-virginia) that confirm 
that it has implemented the required mitigation and monitoring, and 
also show that no impacts of a scale or nature not previously analyzed 
or authorized have occurred as a result of the activities conducted. No 
changes were made from the proposed to the final rule.

Description of the Activity

Overview

    The Navy is currently conducting, and will continue, the 
replacement of Pier 3 at NAVSTA Norfolk, in Norfolk, VA. The 
aforementioned 2022 IHA (as modified) and subsequent renewal covered 
the first year of project activities, and this rule 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). Activities under the rule 
include 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 regulations are valid for a period of 5 years (2023-2028). The 
specified activities may occur at any time during the 5-year period of 
validity of the regulations. The Navy expects pile driving and drilling 
for the entire project to occur on approximately 513 non-consecutive 
days over a 4-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 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).

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[GRAPHIC] [TIFF OMITTED] TR18MY23.007


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[GRAPHIC] [TIFF OMITTED] TR18MY23.008

Detailed Description of Specific Activity

    The project involves the replacement of Pier 3 at NAVSTA 
waterfront. The existing Pier 3 will be completely demolished and a new 
Pier 3 will be constructed immediately north of the existing location 
(Figure 2). The project scope for the replacement of Pier 3 under this 
rule will 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 six 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 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:
     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 (4.5 to 14.5 metric 
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

[[Page 31637]]

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 construction activities considered for this rulemaking 
beginning with Year 2. As indicated above, Year 1 of the Pier 3 
replacement project was authorized under the 2022 IHA and subsequent 
renewal. Therefore, Year 2 of the project aligns with year 1 of the 
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
----------------------------------------------------------------------------------------------------------------
                                  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.
----------------------------------------------------------------------------------------------------------------
    Total Piles Installed....       1,726  ................  ...............  ..........         513  ..........
                              ----------------------------------------------------------------------------------
    Total Piles Removed......       1,661  ................  ...............  ..........  ..........  ..........
----------------------------------------------------------------------------------------------------------------
Note: Estimated construction schedule. Delays may occur due to equipment failure or weather.
* Pre-drilling is permitted to assist with pile installation.

[[Page 31638]]

 
** Denotes piles removed.
*** Year 2 refers to the second year of the Pier 3 replacement project, however it is considered as Year 1 under
  this 2023 rule.

    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 project.

                         Table 2--Summary of Possible Concurrent Pile Driving Scenarios
----------------------------------------------------------------------------------------------------------------
                                                                                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),
                                                                                      2    Rotary Drill (1)
                                                                                          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 CEP- Extraction of 14-inch             4   Vibratory Hammer (3),
                            102.                     timber piles from                4    Rotary Drill (1).
                                                     Pier 3 and Driving of                Vibratory Hammer (2),
                                                     42-inch steel pipe,                   Impact Hammer (2),
                                                     sheet piles, and                      Rotary Drill (1).
                                                     precast concrete
                                                     piles.
                                                                                      4   Vibratory (1), Impact
                                                                                           Hammer (3).
Year 4-Year 5............  Existing Pier 3 and CEP- Extraction of 16- to              2   Vibratory Hammer (1),
                            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.
----------------------------------------------------------------------------------------------------------------

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

Comments and Responses

    NMFS' notice of proposed rulemaking was published in the Federal 
Register on March 9, 2023 (88 FR 14560). That proposed rule described, 
in detail, the Navy's activities, the marine mammal species that may be 
affected by the activities, and the anticipated effects on marine 
mammals. In that proposed rule, we requested public input on the 
request for authorization described therein, our analyses, the proposed 
authorization, and any other aspect of the notice of proposed 
rulemaking, and requested that interested persons submit relevant 
information, suggestions, and comments. The proposed rule was available 
for a 30-day public comment period.
    During the 30-day public comment period, NMFS received one 
substantive comment submission, from a member of the public. NMFS' 
responses to the comments in the submission are provided below, and all 
comments are available online at: https://www.regulations.gov/document/NOAA-NMFS-2022-0110-0001/comment.
    Comment 1: A member of the public noted that the Navy's 
construction work has the potential to cause sediment runoff into the 
marine environment, which can smother marine plants and reduce light 
availability for primary productivity. The individual indicated 
agreement with the mitigation measures as outlined in the notice of 
proposed rulemaking and recommends that extra vegetation be planted and 
heavy monitoring of substrates occur throughout the project. The 
individual also noted concerns with the impact of underwater noise on 
the life history of marine fish species as well as sea turtles.
    Response: NMFS appreciates the commenter's engagement in the 
rulemaking process, but notes that concerns regarding sediment runoff 
are outside NMFS' purview under the MMPA, except inasmuch as such 
impacts may affect marine mammal habitat (including prey). Similarly, 
concerns related to species other than marine mammals (and marine 
mammal habitat), such as sea turtles, are outside NMFS' purview under 
the MMPA. As required under the MMPA, NMFS assessed the impacts of the 
Navy's construction project on marine mammals and their habitat and 
made the necessary findings in support of issuance of this rule and 
subsequent LOA. NMFS notes that mitigation and monitoring prescribed 
will affect the least practicable adverse impact on marine mammals and 
their habitat.
    As described in the proposed rule (88 FR 14560, March 9, 2023), 
NMFS finds that the most likely impact to fish (i.e., potential prey) 
from pile driving activities at the project areas would be temporary 
behavioral avoidance of the area. The duration of fish avoidance of 
this area after pile driving stops is unknown, but a rapid return to 
normal recruitment, distribution and behavior is anticipated. 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.
    Construction activities, in the form of increased turbidity, have 
the potential to adversely affect forage fish in the project area. 
Forage fish form a significant prey base for many marine mammal species 
that occur in the project area. Increased turbidity is expected to 
occur in the immediate vicinity of construction activities. However, 
suspended sediments and particulates are expected to dissipate quickly 
within a single tidal cycle. Given the limited area affected, any 
effects on forage fish are expected to be minor or negligible.
    Comment 2: The commenter indicated concern regarding the length of 
time for which the rule is valid, noting five years is a significant 
amount of time and believes the regulations should be valid for a 
shorter period of time so NMFS is able to reevaluate the success of the 
mitigation and monitoring plan.
    Response: MMPA section 101(a)(5)(A) allows the authorization of 
incidental taking of marine mammals by U.S. citizens incidental to 
specified activities for up to 5 consecutive years, as requested by the 
Navy in this case. Therefore, NMFS has determined that 5 years is an 
appropriate length of time for effectiveness of the rule. Additionally, 
the regulations governing the take of marine mammals incidental to Navy 
construction activities contains an adaptive management component.

[[Page 31639]]

Please see the Adaptive Management section for more detail.
    Comment 3: The individual recommends that trained professionals 
report on any harm to marine life, the use of visual and acoustic 
monitoring techniques, and measures to limit noise pollution in the 
marine environment.
    Response: NMFS concurs with the recommendation to use trained 
professional protected species observers (PSOs), which were included in 
the proposed rule as well as this final rule. These PSOs will provide 
adequate visual monitoring to ensure the Navy complies with the 
requirements outlined in their issued LOA. The Navy will also collect 
acoustic data for specified piles as outlined in their Marine Mammal 
Monitoring Plan. Additionally, the Navy will submit a visual and 
acoustic monitoring report to NMFS annually, well as a comprehensive 
report at the conclusion of the five years. Please see the Mitigation 
and Monitoring and Reporting sections of this final rule for additional 
details.

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 
is 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. Atlantic and Gulf of Mexico SARs. All values 
presented in Table 2 are the most recent available at the time of 
publication, including from the draft 2022 SARs, and are available 
online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

                                              Table 3--Species Likely Impacted by the Specified Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         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,        1729        339
                                                                                                             2018).
    Gray seal \4\...................  Halichoerus grypus.....  Western North Atlantic.  -, -, N             27,300 (0.22, 22,785,        1458       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.


[[Page 31640]]

    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 area for this project and 
take is not expected to occur. Therefore, they are not discussed 
further beyond the explanation provided in the Federal Register 
proposed rule (88 FR 14560, March 9, 2023).
    A detailed description of the species likely to be affected by the 
Navy's project, including brief introductions to the species and 
relevant stocks as well as available information regarding population 
trends and threats, and information regarding local occurrence, were 
provided in the Federal Register proposed rule (88 FR 14560, March 9, 
2023). Since that time, we are not aware of any changes in the status 
of these species and stocks; therefore, detailed descriptions are not 
provided here. Please refer to that Federal Register proposed rule for 
these descriptions. Please also refer to the NMFS website (https://www.fisheries.noaa.gov/find-species) for generalized species accounts.

Unusual Mortality Events

    An unusual mortality event (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. As of April 2023, six 
humpback whales have been found stranded in Virginia. 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.

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

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from the Navy's construction 
activities have the potential to result in Level A and Level B 
harassment of marine mammals in the vicinity of the project area. The 
notice of the proposed rulemaking (88 FR 14560, March 9, 2023) included 
a discussion of the effects of anthropogenic noise on marine mammals 
and the potential effects of underwater noise from the Navy's 
construction activities on marine mammals and their habitat. That 
information and analysis is referenced in this final rule and is not 
repeated here; please refer to the notice of

[[Page 31641]]

proposed rulemaking (88 FR 14560; March 9, 2023).

Estimated Take

    This section provides an estimate of the number of incidental takes 
that may be authorized under this rule, 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 will 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 
shutdown zones encompass the entirely of the auditory injury zones for 
all activities (see Mitigation section). The 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 is authorized for this activity. Below we describe how 
the 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 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 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 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.

[[Page 31642]]

 
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]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 (121.9-cm) 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, California, by Dazey et al. 
(2012) appear to provide the best available proxy source levels for 
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.
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 (2018) 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

[[Page 31643]]

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...............         1482           53         1766          793         1,000
                                                     28-inch Steel Sheets.............         1783           63         2123          954          2512
                       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...............         1002           36         1193          536          1000
                                                     28-inch Steel Sheet..............         1783           63         2123          954          2512
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...............         1002           36         1193          536          1000
                                                     28-inch Steel Sheet..............         1783           63         2123          954          2512
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).
                           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) \1\           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.

[[Page 31644]]

 
4.......  Existing Pier 3  Extraction of 14-             981           87         1450          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 (71-cm) 
steel sheets at CEP-176 and CEP-102 (1,783 m for humpback whale; 63 m 
for bottlenose dolphin; 2,123 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 Whale
    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 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 (two individuals) every 
60 days of pile driving. Therefore, given the number of project days 
expected in each year (Table 1), NMFS has authorized a total of 19 
takes by Level B harassment of humpback whale over the 5-year 
authorization, with no more than 7 takes by Level B harassment in a 
given year.
    The largest Level A harassment zone for low-frequency cetaceans 
extends approximately 1,783 m from the source during impact pile 
driving of the 28-inch steel sheet piles (Table 8). The Navy will 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 did not 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 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 dolphins 
per square kilometer (/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 authorized 28,480 \1\ takes by 
Level B harassment of bottlenose dolphin across all 5 years, with no 
more than 13,190 takes in a given year.
---------------------------------------------------------------------------

    \1\ Note: This total number of takes by Level B harassment 
authorized 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 
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 will be 185 days, Year 3 will be 92 days, Year 4 will be 204 days, 
and Year 5 will 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

[[Page 31645]]

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 will shut down at 500 m for harbor porpoises during the 
aforementioned activity, in addition to shorter distances where 
appropriate for other activities as noted in Table 13 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 authorized 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 Navy at the Chesapeake Bay 
Bridge Tunnel 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 
requested and NMFS authorizeda 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 U.S. 
population of gray seals 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 6-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 authorized (Table 11). 
Therefore, the Navy requested and NMFS authorized five takes by Level B 
harassment. Given the low likelihood of encountering gray seals during 
the project and low number of days in which Level A harassment 
isopleths may exceed shutdown zones, no take by Level A harassment is 
authorized.

    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 Migratory.               0           2,691               0           5,609
                        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 Migratory.               0           3,061               0           1,440
                        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 Migratory.               0          13,190               0           3,023
                        BND--Southern Migratory
                        BND--NC Estuarine
                        Harbor porpoise.........               2               5               0               1
                        Harbor seal.............               0           1,809              26             232
                        Gray seal...............               0               2               0               0
5                       Humpback whale..........               0               2               0               3
                        BND--Northern Migratory.               0             383               0           6,620
                        BND--Southern Migratory
                        BND--NC Estuarine

[[Page 31646]]

 
Harbor porpoise         ........................               0               1               0               3
                        Harbor seal.............               0             435               0           1,115
                        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 authorized is italicized and used to determine percent of
  stock.


    Table 12--Authorized Takes by Level A and Level B Harassment by Species and Stock in Comparison to Stock
                                                    Abundance
----------------------------------------------------------------------------------------------------------------
                                                               Take
     Year            Species         Abundance   --------------------------------      Total        Percent of
                                                      Level A         Level B                          stock
----------------------------------------------------------------------------------------------------------------
2               Humpback whale             1,396               0               6               6            0.43
                 \a\.
                BND--Northern              6,639               0           5,609           2,705           40.74
                 Migratory \b\
                 \c\.
                BND--Southern              3,751  ..............  ..............           2,705           72.10
                 Migratory \b\
                 \c\.
                BND--NC                      823  ..............  ..............             200           24.30
                 Estuarine \b\
                 \c\.
                Harbor porpoise.          95,543               2               4               6            0.01
                Harbor seal.....          61,336              57             949           1,006            1.64
                Gray seal.......          27,300               0               1               1            0.00
3               Humpback whale             1,396               0               3               3            0.21
                 \a\.
                BND--Northern              6,639               0           3,061           1,431           21.55
                 Migratory \b\
                 \c\.
                BND--Southern              3,751  ..............  ..............           1,431           38.15
                 Migratory \b\
                 \c\.
                BND--NC                      823  ..............  ..............             200           24.30
                 Estuarine \b\
                 \c\.
                Harbor porpoise.          95,543               0               3               3            0.00
                Harbor seal.....          61,336               7             537             544            0.89
                Gray seal.......          27,300               0               1               1            0.00
4               Humpback whale             1,396               0               7               7            0.50
                 \a\.
                BND--Northern              6,639               0          13,190           6,495           97.83
                 Migratory \b\
                 \c\.
                BND--Southern              3,751  ..............  ..............           6,495          173.15
                 Migratory \b\
                 \c\.
                BND--NC                      823  ..............  ..............             200           24.30
                 Estuarine \b\
                 \c\.
                Harbor porpoise.          95,543               2               5               7            0.01
                Harbor seal.....          61,336              26           1,783           1,809            2.95
                Gray seal.......          27,300               0               2               2            0.01
5               Humpback whale             1,396               0               3               3            0.21
                 \a\.
                BND--Northern              6,639               0           6,620           3,210           48.35
                 Migratory \b\
                 \c\.
                BND--Southern              3,751  ..............  ..............           3,210           85.58
                 Migratory \b\
                 \c\.
                BND--NC                      823  ..............  ..............             200           24.30
                 Estuarine \b\
                 \c\.
                Harbor porpoise.          95,543               0               3               3            0.00
                Harbor seal.....          61,336               0           1,115           1,115            1.82
                Gray seal.......          27,300               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 will 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.

Mitigation

    In order to issue an LOA under section 101(a)(5)(A) 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,

[[Page 31647]]

    (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 m of construction 
activities, including in-water heavy machinery work not being analyzed 
in this 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 will 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 
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 PSOs 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 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--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

[[Page 31648]]

 
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, shutdown zones
  conservatively reflect individual activity.

    Based on our evaluation of the applicant's measures, as well as 
other measures considered by NMFS, NMFS has determined that the 
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.

Monitoring and Reporting

    In order to issue an LOA for an activity, section 101(a)(5)(A) 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 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 rulemaking; and
     Where a team of three or more PSOs is required, a lead PSO 
or monitoring coordinator must be designated. The lead PSO 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

[[Page 31649]]

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 1,000 m. All other activities will require a minimum of 
two PSOs. For activities in Tables 8, 9, and 10, with Level B 
harassment zones larger than 3,000 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 
1,000 m will 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 shutdown zones, the Navy shall contact NMFS to alter PSO 
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, PSOs 
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.
[GRAPHIC] [TIFF OMITTED] TR18MY23.009

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 will 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.

[[Page 31650]]

[GRAPHIC] [TIFF OMITTED] TR18MY23.010

    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, and 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,

[[Page 31651]]

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 [mu]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:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     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 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 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

[[Page 31652]]

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 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 has authorized no more than 8 
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 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 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 is of 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; and
     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 monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
activity will have a negligible impact on all affected marine mammal 
species or stocks.

Small Numbers

    As noted 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 authorized 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

[[Page 31653]]

split evenly between the northern and southern coastal migratory 
stocks. Based on the consideration of various factors as described 
below, we have 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 of the proposed rule.
    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 and 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 km 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 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 authorized 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 will 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 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 will 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 will contain an adaptive management 
component. The reporting requirements associated with this 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.

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 promulgation of 
regulations and subsequent issuance of incidental take authorization) 
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

[[Page 31654]]

anticipated serious injury or mortality) of the Companion Manual for 
NOAA 216-6A, which do not individually or cumulatively have the 
potential for significant impacts on the quality of the human 
environment and for which we have not identified any extraordinary 
circumstances that would preclude this categorical exclusion. 
Accordingly, NMFS has determined that the action qualifies to be 
categorically excluded from further review under NEPA.

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 ensure 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 LOAs, 
NMFS consults internally whenever we propose to authorize take for 
endangered or threatened species.
    No incidental take of ESA-listed species is authorized 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.

Classification

    Pursuant to the procedures established to implement Executive Order 
12866, the Office of Management and Budget has determined that this 
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 rule, if adopted, would not have significant 
economic impact on a substantial number of small entities. The Navy is 
the sole entity that would be subject to the requirements in these 
regulations, and the Navy is not a small governmental jurisdiction, 
small organization, or small business, as defined by the RFA. 
Therefore, a regulatory flexibility analysis is not required and none 
has been prepared.
    This rule does not contain a collection-of-information requirement 
subject to the provisions of the Paperwork Reduction Act because the 
applicant is a Federal agency.

Waiver of Delay in Effective Date

    The Assistant Administrator for Fisheries has determined that there 
is good cause under the Administrative Procedure Act (5 U.S.C. 
553(d)(3)) to waive the 30-day delay in the effective date of the 
measures contained in the final rule. The Navy is the only entity 
subject to these regulations, and it has informed NMFS that it requests 
that this final rule take effect as soon as possible. Any further delay 
in promulgating the final rule could result in a delay to the project 
schedule that would extend the completion of the project and cause 
further risks to the Virginia Class submarines schedule. In addition, 
in-water work at Pier 3 and associated fender systems are critical to 
timely completion of the overall project. Delaying the completion of 
ongoing work will have increased risk on other mission critical work, 
as some of the construction components cannot begin until others are 
started or in some cases completed. Moreover, the contractor is onsite 
and currently working under the existing IHA renewal (88 FR 20133, 
April 5, 2023). However, this renewal does not include all piles the 
Navy plans to install or remove within the first year of the rule in 
order to stay on schedule. Therefore, the Navy is ready to operate 
under the LOA immediately. For these reasons, the Assistant 
Administrator finds good cause to waive the 30-day delay in the 
effective date. In addition, the rule allows authorization of 
incidental take of marine mammals that would otherwise be prohibited 
under the statute. Therefore, the rule will relieve restrictions under 
the MMPA, which provides a separate basis under the Administrative 
Procedure Act (5 U.S.C. 553(d)(1)) to waive the 30-day delay in 
effective date.

List of Subjects in 50 CFR Part 217

    Exports, Fish, Imports, Indians, Labeling, Marine mammals, 
Penalties, Reporting and recordkeeping requirements, Seafood, 
Transportation.

    Dated: May 9, 2023.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, NMFS amends 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]

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


Sec.  217.110  Specified activity and geographical region.

    (a) Regulations under 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 under this subpart are effective from May 18, 2023, 
through May 18, 2028.


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 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 under 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:

[[Page 31655]]

    (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 under 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) Should environmental conditions deteriorate such that marine 
mammals within the entire shutdown zone would not be visible (e.g., 
fog, heavy rain, night), the Holder shall delay in-water construction 
activities until observers are confident marine mammals within the 
shutdown zone could be detected.
    (9) 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.
    (10) 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.
    (11) 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 a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization.
    (3) 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.
    (4) One PSO must be designated as lead PSO or monitoring 
coordinator. The lead PSO must have prior experience performing the 
duties of a PSO during construction activity pursuant to a NMFS-issued 
incidental take authorization.
    (5) PSOs 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 PSOs 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 PSOs 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 1,000 m, a minimum 
of three PSOs 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

[[Page 31656]]

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.); and
    (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, 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 the regulations 
under this subpart, 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 the regulations 
under this subpart.
    (c) If an LOA expires prior to the expiration date of the 
regulations under this subpart, 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
    (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 the regulations under this subpart.
    (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 specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for the regulations under this subpart; 
and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOA under the regulations under this 
subpart were implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation,

[[Page 31657]]

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 for the regulations under this subpart;
    (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 the regulations under 
this subpart 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. 2023-10168 Filed 5-17-23; 8:45 am]
BILLING CODE 3510-22-P