[Federal Register Volume 86, Number 195 (Wednesday, October 13, 2021)]
[Proposed Rules]
[Pages 56857-56884]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-21426]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 210924-0196]
RIN 0648-BK69


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to U.S. Navy Construction at Naval 
Station Newport in Newport, Rhode Island

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

ACTION: Proposed rule; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Navy (Navy) for 
authorization to take marine mammals incidental to construction 
activities for bulkhead replacement and repairs at Naval Station 
Newport (NAVSTA Newport) over the course of five years (2022-2027). As 
required by the Marine Mammal Protection Act (MMPA), NMFS is proposing 
regulations to govern that take, and requests comments on the proposed 
regulations. NMFS will consider public comments prior to making any 
final decision on the issuance of the requested MMPA authorization and 
agency responses will be summarized in the final notice of our 
decision.

DATES: Comments and information must be received no later than November 
12, 2021.

ADDRESSES: You may submit comments on this document, identified by 
NOAA-NMFS-2021-0096, by the following method:
     Electronic submission: Submit all electronic public 
comments via the Federal e-Rulemaking Portal. Go to https://www.regulations.gov and enter NOAA-NMFS-2021-0096 in the Search box, 
click the ``Comment'' icon, complete the required fields, and enter or 
attach your comments.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. All comments received are a part of the 
public record and will generally be posted for public viewing on 
www.regulations.gov without change. All personal identifying 
information (e.g., name, address), confidential business information, 
or otherwise sensitive information submitted voluntarily by the sender 
will be publicly accessible. NMFS will accept anonymous comments (enter 
``N/A'' in the required fields if you wish to remain anonymous). 
Attachments to electronic comments will be accepted in Microsoft Word, 
Excel, or Adobe PDF file formats only.

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

SUPPLEMENTARY INFORMATION:

Availability

    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-construction-naval-station-newport-rhode-island. In case of problems accessing these documents, please call the 
contact listed above (see FOR FURTHER INFORMATION CONTACT).

Purpose and Need for Regulatory Action

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

Legal Authority for the Proposed Action

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

Summary of Major Provisions Within the Proposed Rule

    Following is a summary of the major provisions of this proposed 
rule regarding Navy construction activities. These measures include:
     Required monitoring of the construction areas to detect 
the presence of marine mammals before beginning construction 
activities;
     Shutdown of construction activities under certain 
circumstances to avoid injury of marine mammals; 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

    Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1361 et seq.) directs 
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, regulations are issued, and notice is 
provided to the public.
    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

[[Page 56858]]

availability of the species or stock(s) for taking for subsistence uses 
(where relevant), and if the permissible methods of taking and 
requirements pertaining to the mitigation, monitoring and reporting of 
the takings are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering (Level B harassment).

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 an 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 of the Companion Manual for NOAA 
Administrative Order 216-6A, which do not individually or cumulatively 
have the potential for significant impacts on the quality of the human 
environment and for which we have not identified any extraordinary 
circumstances that would preclude this categorical exclusion. 
Accordingly, NMFS has preliminarily determined that the issuance of 
this proposed rule qualifies to be categorically excluded from further 
NEPA review.
    Information in the Navy's application and this document 
collectively provide the environmental information related to proposed 
issuance of these regulations and subsequent incidental take 
authorization for public review and comment. We will review all 
comments submitted in response to this document prior to concluding our 
NEPA process or making a final decision on the request for incidental 
take authorization.

Summary of Request

    In July 2020, NMFS received a request from the Navy requesting 
authorization to take small numbers of seven species of marine mammals 
incidental to construction activities including bulkhead replacement 
and repairs at NAVSTA Newport. The Navy has requested regulations that 
would establish a process for authorizing such take via a LOA. NMFS 
reviewed the Navy's application, and the Navy provided responses 
addressing NMFS' questions and comments on February 22, 2021. The 
application was deemed adequate and complete and published for public 
review and comment on May 19, 2021 (86 FR 27069). We did not receive 
substantive comments on that notice and request for comments and 
information.
    The Navy requests authorization to take a small number of seven 
species of marine mammals by Level A and B harassment. Neither the Navy 
nor NMFS expects serious injury or mortality to result from this 
activity. The proposed regulations would be valid for five years (2022-
2027).

Description of Proposed Activity

Overview

    The Navy proposes to replace or repair several sections of 
deteriorating, unstable, hazardous, and eroding bulkhead, sheet pile, 
and revetment (approximately 2,730 total linear feet (ft)) along the 
Coddington Cove waterfront of NAVSTA Newport. Over time, the existing 
storm sewer systems and bulkheads along the Coddington Cove waterfront 
have severely degraded due to erosion from under-capacity stormwater 
system piping and aging infrastructure. This impacts the ability of the 
installation to minimize shoreline erosion and minimize safety risks 
from associated upland subsidence, while also maintaining potential 
berthing space. The Navy plans to conduct necessary work, including 
impact and vibratory pile driving, to repair and replace bulkheads over 
five years.

Dates and Duration

    The proposed regulations would be valid for a period of five years 
(2022-2027). The specified activities may occur at any time during the 
5-year period of validity of the proposed regulations. The Navy expects 
pile driving to occur on approximately 222 non-consecutive in-water 
pile driving days over the five-year duration. Pile driving activities 
are anticipated to be completed within 4 years. However, because the 
proposed construction is dependent on the allocation of funding, the 
Navy is requesting that the LOA be issued for the entire 5-year 
construction period to ensure flexibility in the project schedule. 
Table 1 provides the anticipated construction schedule for the proposed 
activities.

                                                            Table 1--Coddington Cove Bulkhead Replacement and Repair Summary Schedule
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                                                                         Revetment
              Section ID                 Bulkhead  replacement  (lf)    replacement        Outfalls  replaced      Dredging  area     Dredging                Construction start date
                                                                           (lf)                                         (ft2)        volume (cy)
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S45...................................  310.........................             250  Yes (3)....................           8,400             650  May 15, 2022.
S366..................................  90..........................               0  Yes (1)....................           1,350             100  October 15, 2023.
Pier 1................................  100.........................               0  No.........................           1,500             120  October 15, 2023.
LNG...................................  650.........................               0  Yes (2)....................           9,750             760  October 15, 2024.
S499/Pier 2...........................  510.........................              90  Yes (5)....................           9,000             700  October 15, 2025.
S50...................................  730 (repair)................               0  Yes (2)....................               0               0  October 15, 2026.
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Source: NAVFAC Mid-Atlantic 2018.

Specific Geographic Region

    NAVSTA Newport, encompasses 1,399 acres extending 6-7 mi along the 
western shore of Aquidneck Island in the towns of Portsmouth, Rhode 
Island, and Middletown, Rhode Island, and the City of Newport, Rhode 
Island. The base footprint also includes the northern third of Gould 
Island in the town of Jamestown, Rhode Island. The base is located in 
the southern part of the state near where Narragansett Bay adjoins the 
Atlantic Ocean. The locations of the proposed bulkhead repairs at 
Coddington Cove are identified in Figure 1.

[[Page 56859]]

    Narragansett Bay is one of Rhode Island's principle water features. 
Narragansett Bay is approximately 22 nautical miles (nmi) (40 
kilometers (km)) long and 7 nmi (16 km) wide. The average depth of 
Narragansett Bay is 29 ft. The Narragansett Bay's most prominent 
bathymetric feature is a submarine valley that runs between Conanicut 
and Aquidneck Islands to Rhode Island Sound, and defines the East 
Passage of Narragansett Bay. The shipping channel in the East Passage 
serves as the primary shipping channel for the rest of Narragansett Bay 
and is generally 100 ft deep. The shipping channel from the lower East 
Passage splits just south of Gould Island with the western shipping 
channel heading to Quonset Point and the eastern shipping channel 
heading to Providence and Fall River (Navy, 2008).
    Coddington Cove is located on the western side of Aquidneck Island 
and is a protected embayment formed by Coddington Point to the south 
and a 4,000 ft long rubble-mound breakwater to the north. It covers an 
area of 1.6 square nmi with water depths up to 50 ft The area is a 
Restricted Area and is closed to all commercial and recreational vessel 
traffic, unless authorized by the appropriate personnel (Navy, 2008). 
According to a 2015 bathymetric survey of Coddington Cove, water depths 
in the proposed project area are less than 34 ft mean lower low water. 
Water depths in the pier are artificially deep to accommodate the 
berthing of large ships (NAVFAC, 2015).
BILLING CODE 3510-22-P

[[Page 56860]]

[GRAPHIC] [TIFF OMITTED] TP13OC21.000

BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The proposed project is the replacement or repair of several 
sections of deteriorating, unstable, hazardous, and eroding bulkhead 
along the Coddington Cove waterfront of NAVSTA Newport. As part of the 
replacement/repairs, existing stormwater outfalls in the repair areas 
would also be replaced or improved. Improvements would include changing 
outfall pipe material and/or changing outfall pipe diameter. Stormwater 
outfall improvements would reduce flooding and improve conveyance, as 
well as minimize shoreline erosion and associated sedimentation of 
adjacent receiving waters. The specific sections proposed for bulkhead 
repair and replacement are described from north to

[[Page 56861]]

south in the following paragraphs and are summarized in Table 2 at the 
end of this section.
    Section S499/Pier 2: Currently, this section of bulkhead is in 
serious condition and has a high priority for replacement/repair 
because the steel sheet pile has widespread moderate-to-advanced 
corrosion across multiple zones. There are also significant section 
losses of steel sheet pile and timber planking occurring at multiple 
locations. In addition, the protective coatings have separated and 
failed along the bulkhead.
    Replacement and repair of Section S499/Pier 2 includes the 
demolition of the existing north marginal wharf; excavation and 
replacement of approximately 310 ft of existing steel bulkhead 
underneath and north of Pier 2; and replacement of approximately 90 ft 
of rip rap revetment north of Pier 2. Demolition of the marginal wharf 
would include the removal of approximately 8,500 square ft (ft\2\) of 
concrete decking and the demolition of 80 (36-inch (in) diameter) 
concrete encased piles.
    The existing bulkhead structure would be replaced with a new 
combined wall system (see Figure 1-3 of the application). Because of 
the proximity of important buildings, a deadman and tie rod anchoring 
system cannot be installed at this location. Approximately 140 (70 
pairs) (31.5-in) sheet piles; 35 (42-in) steel pipe piles; and 79 (14-
in) H-piles would be installed approximately 12 in seaward of the 
existing bulkhead using a vibratory and impact hammer, as necessary. 
The existing bulkhead would be excavated landside and cut off 
approximately 5 ft below ground level. The interstitial space would be 
backfilled with stone.
    Section S366: In its current condition, this section of bulkhead is 
in a serious condition with a high priority for replacement/repair 
because the steel sheet piling exhibits heavy corrosion with numerous 
areas that exhibit 100 percent loss of section, as well as separation 
of the protective coating, vegetation growth through the structure, and 
rust pack. The timber planking protecting the concrete encasement has 
rotted at the waterline in some areas.
    Replacement of Section S366 would include the demolition and 
replacement of approximately 90 ft of existing steel sheet pile 
bulkhead just north of Pier 1. The existing bulkhead would then be 
replaced with a new deadman anchored king pile system. The system would 
consist of approximately 28 (14 pairs) (22.5-in) Z-shaped sheet piles; 
15 (30-in) steel pipe piles; and 14 (14-in) H-piles. These piles would 
be installed approximately 1ft in front of the existing bulkhead using 
a combination of vibratory and impact hammers, as necessary. The 
existing steel sheet pile wall would be excavated landside to a depth 
of approximately 8-10 ft and cut off at the limit of excavation. An 8-
ft high concrete deadman anchor system would be installed approximately 
50 ft behind the new bulkhead and would be connected to the bulkhead by 
tie rods (see Figure 1-6 of the application). Stone would be used as 
the backfill material to allow a rapid drop down of the water at the 
back of the bulkhead after a severe storm.
    Section Pier 1: Pier 1 was not accessible during the condition 
assessment and is assumed to be in similar condition as S366. The 
waterside inspection was limited due to the presence of vessels and 
other obstacles that would not allow the inspection vessel to pass 
(NAVFAC Mid-Atlantic, 2018).
    Section Pier 1 includes demolition and replacement of approximately 
100 ft of existing steel sheet pile bulkhead underneath Pier 1 (see 
Figure 1-7 of the application). In order to access the bulkhead 
underneath the pier, partial demolition of Pier 1 would occur. 
Demolition would involve the removal of concrete decking, but the 
removal of support piles is not anticipated.
    Should demolition of the underlying support piles be required to 
perform bulkhead replacement/repair, the use of impact or vibratory 
hammers would not be required. Piles would be cut off at mudline or 
extracted with a sling (i.e., dead pull). The existing steel sheet pile 
wall would be excavated landside to a depth of approximately 13 ft 
below ground surface and cut off at the limit of excavation. The 
existing bulkhead would then be replaced with a new deadman and tie rod 
anchored sheet pile system. The system would consist of approximately 
54 (27 pairs) (22.5-in) Z-shaped sheet piles and approximately 26 (14-
in) H-piles. These piles would be installed approximately 1ft in front 
of the existing bulkhead using a combination of vibratory and impact 
hammers, as necessary. Bulkhead replacement would include shoreline 
dredging to a depth of approximately 14 ft at the toe of the existing 
bulkhead to ensure proper installation of the new bulkhead.
    Section S45: In its current condition, this section of bulkhead is 
in serious condition with a high priority for replacement/repair 
because the steel sheet piles and cap exhibit heavy corrosion with 
numerous areas that exhibit 100 percent loss of section resulting in 
extensive landside erosion.
    Replacement of Section S45 would include the demolition and 
replacement of approximately 310 ft of existing steel sheet pile 
bulkhead just south of Pier 1. The existing bulkhead would then be 
replaced with a new deadman anchored king pile system. The system would 
consist of approximately 4 (30-in) steel pipe piles; 160 (80 pairs) 
(22.5-in) Z-shaped sheet piles; and approximately 76 (14-in) H-piles. 
These piles would be installed approximately 1ft in front of the 
existing bulkhead using a combination of vibratory and impact hammers, 
as necessary. The existing steel sheet pile wall would be excavated 
landside to a depth of approximately 10 ft below ground surface and cut 
off at the limit of excavation (see Figure 1-8 of the application).
    Section LNG: In its current condition, this section of bulkhead is 
in serious condition with high priority for replacement/repair due to 
heavy corrosion with numerous areas that exhibit 100 percent loss of 
section. Where the steel sheet piling is in poor condition, there is 
extensive landside erosion.
    Section LNG includes excavation and replacement of approximately 
650 ft of existing steel bulkhead south of the T-Pier. The existing 
bulkhead would be replaced with a new deadman anchored sheet pile 
system. The system would be similar to the system installed at Pier 1 
and would consist of approximately 346 (173 pairs) (22.5-in) Z-shaped 
sheet piles; and approximately 164 (14-in) H-piles. These piles would 
be installed approximately 1ft in front of the existing bulkhead using 
a combination of vibratory and impact hammers. The existing steel sheet 
pile wall would be excavated landside to a depth of approximately 13ft 
below ground surface and cut off at the limit of excavation.

[[Page 56862]]



                                                      Table 2--Bulkhead Pile Installation Activity
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                                                                                                                                  Maximum      Maximum
                                                                                                                    Vibratory    number of    number of
       Facility          Method of pile       Pile type          Pile Size        Number of sheets    Strikes per    driving       piles         pile
                            driving                                                 (pairs)/piles         pile     minutes per   installed     driving
                                                                                                                       pile       per day        days
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S45..................  Vibratory/Impact.  Z-shaped Steel     3.75 ft per pair/  80 pair.............          530           13           10           27
                                           Sheet Pile.        22.5-in each.
                       Impact...........  Steel Pipe Pile..  30-in............  4...................          530           NA            2            4
                       Vibratory........  Steel H-pile.....  14-in............  76..................           NA           10           12           13
S366.................  Vibratory/Impact.  Z-shaped Steel     3.75 ft per pair/  14 pair.............          530           13           10            5
                                           Sheet Pile.        22.5-in each.
                       Impact...........  Steel pipe pile..  30-in diameter...  15..................          530           NA            2           15
                       Vibratory........  Steel H-pile.....  14-in............  14..................           NA           10           12            3
S499/Pier 2..........  Vibratory/Impact.  Z-shaped Steel     5.25 ft per pair/  70 pair.............          530           13            8           23
                                           Sheet Pile.        31.5-in each.
                       Impact...........  Steel Pipe Pile..  42-in............  35..................          530           NA            4           18
                       Vibratory........  Steel H-pile.....  14-in............  79..................           NA           10           12           14
LNG                    Vibratory/Impact.  Z-shaped Steel     3.75 ft per pair/  173 pair............          530           13           10           58
                                           Sheet Pile.        22.5-in each.
                       Vibratory........  Steel H-pile.....  14-in............  164.................           NA           10           12           28
Pier 01..............  Vibratory/Impact.  Z-shaped Steel     3.75 ft per pair/  27 pair.............          530           13           10            9
                                           Sheet Pile.        22.5-in each.
                                                                               -------------------------------------------------------------------------
                       Vibratory........  Steel H-pile.....  14-in............  26..................           NA           10           12            5
                                                                               -------------------------------------------------------------------------
    Total sheet piles  364/413..........
     pairs/pipe and H-
     piles installed.
                                                                               -------------------------------------------------------------------------
    Total days pile    .................  .................  .................  ....................  ...........  ...........  ...........          222
     driving.
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Legend: NA = not applicable, ft = foot; Start date of in-water work and duration are to be determined.

    Pile installation would occur using land-based or barge-mounted 
cranes, as appropriate. Cranes would be equipped with both vibratory 
and impact hammers. Piles would be installed initially using vibratory 
means and then finished with impact hammers, as necessary. Impact 
hammers would also be used where obstructions or sediment conditions do 
not permit the efficient use of vibratory hammers. Impact hammers would 
utilize soft start techniques to minimize noise impacts in the water 
column. The Navy does not yet know what type/size of hammers would be 
used to complete the work. For purposes of this analysis, underwater 
noise was modeled without accounting for potential noise minimization 
measures.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the Navy's application summarize available 
information regarding status and trends, distribution and habitat 
preferences, and behavior and life history, of the potentially affected 
species. Additional information regarding population trends and threats 
may be found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS's 
website (https://www.fisheries.noaa.gov/find-species).
    Table 3 lists all species or stocks for which take is expected and 
proposed for authorization, 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. For taxonomy, we follow Committee on Taxonomy (2021). 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 mortality is 
anticipated or authorized here, PBR and annual serious injury and 
mortality from anthropogenic sources are included here as gross 
indicators of the status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS' stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. Atlantic and Gulf of Mexico SARs (e.g., Hayes et al. 2021). 
All values presented in Table 3 are the most recent available at the 
time of publication and are available in the 2020 SARs (Hayes et al. 
2021).

[[Page 56863]]



                                          Table 3--Marine Mammal Species Likely To Occur Near the Project Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                             Stock abundance  (CV,
                                                                                         ESA/MMPA  status;    Nmin,  most recent               Annual M/
             Common name                  Scientific name               Stock           strategic  (Y/N) 1   abundance  survey) 2      PBR        SI 3
 
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Atlantic white-sided dolphin....  Lagenorhynchus acutus..  Western North Atlantic.  -, -; N             93,233 (0.71; 54,443;         544         26
                                                                                                             2016).
    Common dolphin..................  Delphinus delphis......  Western North Atlantic.  -, -; N             172,974 (0.21;              1,452        399
                                                                                                             145,216; 2016).
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  Gulf of Maine/Bay of     -, -; N             95,543 (0.31; 74,034;         851        217
                                                                Fundy.                                       2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Western North Atlantic.  -,-; N              75,834 (0.15; 66,884,       2,006        350
                                                                                                             2012).
    Gray seal.......................  Halichoerus grypus.....  Western North Atlantic.  -,-; N              27,131 (0.19, 23,158,       1,389      4,729
                                                                                                             2016)\4\.
    Harp seal.......................  Pagophilus               Western North Atlantic.  -,-; N              7,400,000.............    unknown    232,422
                                       groenlandicus.
    Hooded seal.....................  Cystophora cristata....  Western North Atlantic.  -,-; N              593,500...............    unknown      1,680
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable.
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
  fisheries, ship strike). Annual Mortality/Serious Injury (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 abundance value and the associated PBR value reflect the U.S. population only. Estimated abundance for the entire Western North Atlantic stock,
  including animals in Canada, is 451,131. The annual M/SI estimate is for the entire stock.

    As indicated above, all seven species in Table 3 temporally and 
spatially co-occur with the activity to the degree that take is 
reasonably likely to occur, and we have proposed authorizing take. 
Several depleted species of whales occur seasonally in the waters off 
Rhode Island including Humpback (Megaptera novaeangliae), Fin 
(Balaenoptera physalus), Sei (Balaenoptera borealis), Sperm (Physeter 
macrocephalus) and North Atlantic Right whales (Eubaleana glacialis). 
These whales are seasonally present in New England waters; however, due 
to the depths of Narragansett Bay and near shore location of the 
project area, these listed marine mammals are unlikely to occur. 
Therefore, no takes were requested and none are anticipated or proposed 
for authorization by NMFS and they are not discussed further.

Atlantic White-Sided Dolphin

    Atlantic white-sided dolphins are found in the temperate waters of 
the North Atlantic and specifically off the coast of North Carolina to 
Maine in U.S. waters (NOAA Fisheries, 2020a). The Gulf of Maine 
population of white-sided dolphin primarily occurs in continental shelf 
waters from Hudson Canyon to Georges Bank, and in the Gulf of Maine and 
lower Bay of Fundy. From January to May they occur in low numbers from 
Georges Bank to Jeffreys Ledge (off New Hampshire). They are most 
common from June through September from Georges Bank to lower Bay of 
Fundy, with densities declining from October through December (Hayes et 
al., 2019).
    Since stranding recordings for the Atlantic white-sided dolphin 
began in Rhode Island in the late 1960s, this species has become the 
third most frequently recorded small cetacean. There are occasional 
unconfirmed opportunistic reports of white-sided dolphins in 
Narragansett Bay, typically in fall and winter. Atlantic white-sided 
dolphins in Rhode Island are inhabitants of the continental shelf, with 
a slight tendency to occur in shallower water in the spring when they 
are most common (approximately 64 percent of records). Seasonal 
occurrence of Atlantic white-sided dolphins decreases significantly 
following spring with 21 percent of records in summer, 10 percent in 
winter, and 7.6 percent in fall (Kenny and Vigness-Raposa, 2010).

Common Dolphin

    The common dolphin is one of the most widely distributed species of 
cetaceans, found world-wide in temperate and subtropical seas. In the 
North Atlantic, they are common along the shoreline of Massachusetts 
and at sea sightings have been concentrated over the continental shelf 
between the 100-meter (m) and 2000-m isobaths over prominent underwater 
topography and east to the mid-Atlantic Ridge. The common dolphin can 
be found from Cape Hatteras northeast to Georges Bank from mid-January 
to May and in Gulf of Maine from mid-summer to autumn (Hayes et al., 
2019).
    Common dolphins occur in the Rhode Island waters (encompassing 
Narragansett Bay, Block Island Sound, Rhode Island Sound, and nearby 
coastal and continental shelf areas) year-round. They occur across much 
of the shelf but most commonly in waters deeper than approximately 60 
m. Seasonality is not particularly strong, but sightings are more 
common in spring at approximately 35 percent of records followed by 26 
percent in summer, 22 percent in winter, and 18 percent in fall (Kenny 
and Vigness-Raposa, 2010).
    Strandings occur year-round. In the stranding record for Rhode 
Island, common dolphins are the second most frequently stranded 
cetacean (exceeded only by harbor porpoises) and the most common 
delphinid. There were 23 strandings in Rhode Island between 1972 and 
2005 (Kenny and Vigness-Raposa, 2010). A common dolphin was

[[Page 56864]]

most recently recorded in Narragansett Bay in October of 2016 (Hayes et 
al., 2019). There are no recent records of common dolphins far up 
rivers, however such occurrences would only show up in the stranding 
database if the stranding network responded, and there is no 
centralized clearinghouse for opportunistic sightings of that type. In 
Rhode Island, there are occasional opportunistic reports of common 
dolphins in Narragansett Bay up as far as the Providence River, usually 
in winter.

Harbor Porpoise

    Harbor porpoises are found in northern temperate and subarctic 
coastal and offshore waters in both the Atlantic and Pacific Oceans. In 
the western North Atlantic, harbor porpoises are found in the northern 
Gulf of Maine and southern Bay of Fundy region in waters generally less 
than 150 m deep, primarily during the summer (July to September). 
During fall (October to December) and spring (April to June), harbor 
porpoises are widely dispersed between New Jersey and Maine. Lower 
densities of harbor porpoises occur during the winter (January to 
March) in waters off New York to New Brunswick, Canada (Hayes et al., 
2019).

Harbor Seal

    Harbor seals occur in all nearshore waters of the North Atlantic 
and North Pacific Oceans and adjoining seas above approximately 
30[deg]N (Burns, 2009). They are year-round residents in the coastal 
waters of eastern Canada and Maine, occurring seasonally from southern 
New England to New Jersey from September through late May. Harbor 
seals' northern movement occurs prior to pupping season that takes 
place from May through June along the Maine coast. In autumn to early 
winter, harbor seals move southward from the Bay of Fundy to southern 
New England (Hayes et al., 2019). Overall, there are five recognized 
subspecies of harbor seal, two of which occur in the Atlantic Ocean. 
The western Atlantic harbor seal is the subspecies likely to occur in 
the proposed project area. There is some uncertainly about the overall 
population stock structure of harbor seals in the western North 
Atlantic Ocean. However, it is theorized that harbor seals along the 
eastern U.S. and Canada are all from a single population (Temte et al., 
1991).
    Harbor seals are regularly observed around all coastal areas 
throughout Rhode Island, and occasionally well inland up bays, rivers, 
and streams. In general, rough estimates indicate that approximately 
100,000 harbor seals can be found in New England waters (DeAngelis, 
2020). It should be noted for all the seals that the available data are 
strongly dominated by stranding records, which comprised 446 out of 507 
total records for harbor seals (88 percent) (Kenny and Vigness-Raposa, 
2010). Seals are very difficult to detect during surveys, since they 
tend to be solitary and the usual sighting cue is only the seal's head 
above the surface. Of the available records, 52.5 percent are in 
spring, 31.2 percent in winter, 9.5 percent in summer, and 6.9 percent 
in fall. In Rhode Island, there are no records offshore of the 90-m 
isobath. Based on seasonal monitoring in Rhode Island, seals begin to 
arrive in Narragansett Bay in September, with numbers slowly increasing 
in March before dropping off sharply in April. By May, seals have left 
Narragansett Bay (DeAngelis, 2020).
    Seasonal nearshore marine mammal surveys were conducted at NAVSTA 
Newport between May 2016 and February 2017. The surveys were conducted 
along the western shoreline of Coasters Harbor Island northward to 
Coggeshall Point and eastward to include Gould Island. The only species 
that was sighted during the survey was harbor seal. During the spring 
survey, one harbor seal was sighted on 12 May 2016. The seal was 
observed near the surface of the water and engaged in several small 
dives during the encounter. A group of three harbor seals was sighted 
on 1 February 2017, during the winter survey. All three of the harbor 
seals were at the surface and watched the vessel pass. One dead harbor 
seal carcass was observed in the 12 May 2016 survey and reported to the 
Mystic Aquarium Stranding Network (Moll et al., 2016, 2017; Navy, 
2017b).
    In Rhode Island waters, harbor seals prefer to haul out on well-
isolated intertidal rock ledges and outcrops. Numerous Naval Station 
employees have reported seals hauled out on an intertidal rock ledge 
north-northwest of Coddington Point named ``The Sisters'' that is 0.9 
miles from the project area (see Figure 4-1 of the application) (NUWC 
Division, 2011). This haulout has been studied by the NUWC Division 
Newport since 2011 and has demonstrated a steady increase in use during 
winter months when harbor seals are present in the bay. Harbor seals 
are rarely observed at The Sisters haulout in the early fall 
(September-October) but consistent numbers in mid-November (0-10 
animals) are regularly observed with a gradual increase of 20+ animals 
until peak numbers in the upper 40s occur during March, typically at 
low tide. The number of harbor seals begins to drop off in April, and 
by mid-May they are not observed hauled out at all (DeAngelis, 2020). 
Haulout spaces at The Sisters haulout site is primarily influenced by 
tide level, swell, and wind direction (splashing the haul out) (Moll et 
al., 2017; DeAngelis, 2020).
    Including The Sisters haulout, there are 22 haul out sites in 
Narragansett Bay (see Figure 4-1 of the application); however, none of 
these 22 other haulouts are within the project area. During a one-day 
Narragansett Bay-wide count in 2018, there were at least 423 seals 
observed, and all 22 haulout sites were represented. Preliminary 
results from the bay-wide count for 2019 recorded 572 harbor seals; 
this count also included counts from Block Island (DeAngelis, 2020).

Gray Seal

    The Western North Atlantic stock of gray seal occurs in the project 
area. The western North Atlantic stock is centered in Canadian waters, 
including the Gulf of St. Lawrence and the Atlantic coasts of Nova 
Scotia, Newfoundland, and Labrador, Canada, and the northeast U.S. 
continental shelf (Hayes et al. 2017). In general, this species can be 
found year-round in the coastal waters of the Gulf of Maine (Hayes et 
al., 2019).
    Gray seal occurrences in Rhode Island are mostly represented by 
stranding records--155 of 193 total records (80 percent). Gray seal 
records in the region are primarily from the spring (approximately 87 
percent), with much smaller numbers in all other seasons (5.7 percent 
in winter, 5.2 percent in summer, and 2.1 percent in fall). Strandings 
were broadly distributed along ocean-facing beaches in Long Island and 
Rhode Island, with a few spring records in Connecticut (Kenny and 
Vigness-Raposa, 2010). As with other seals, habitat use by gray seals 
in Rhode Island is poorly known. They are seen mainly when stranded or 
hauled out and infrequently at sea. There are very few observations of 
gray seals in Rhode Island other than strandings. The annual numbers of 
gray seal strandings in the Rhode Island study area since 1993 have 
fluctuated markedly, from a low of 1 in 1999 to a high of 24 in 2011 
(Kenney, 2020). The very strong seasonality observed in gray seal 
occurrence in Rhode Island between March and June is clearly related to 
the timing of pupping in January-February. Most stranded individuals 
encountered in Rhode Island area appear to be post-weaning juveniles 
and starved or starving juveniles (Nawojchik, 2002; Kenney, 2005). 
Annual informal surveys conducted since 1994 observed a small number of 
gray seals in Narragansett Bay in 2016 (ecoRI News, 2016).

[[Page 56865]]

Harp Seal

    The harp seal is a highly migratory species, and its range can 
extend from the Canadian Arctic to New Jersey. In U.S. waters, the 
species has an increasing presence in the coastal waters between Maine 
and New Jersey and are considered members of the western North Atlantic 
stock with general presence from January through May (Hayes et al., 
2019).
    Harp seals in Rhode Island are known almost exclusively from 
strandings (approximately 98 percent). Strandings are widespread on 
ocean-facing beaches throughout Long Island and Rhode Island and the 
records are almost entirely from spring (approximately 68 percent) and 
winter (approximately 30 percent). Harp seals are nearly absent in 
summer and fall. Harp seals also make occasional appearances well 
inland up rivers (Kenny and Vigness-Raposa, 2010). During late winter 
of 2020, a healthy harp seal was observed hauled out and resting near 
``The Sisters'' haulout site (DeAngelis, 2020).

Hooded Seal

    The hooded seal is a highly migratory species, and its range can 
extend from the Canadian Arctic to as far south as Puerto Rico 
(Mignucci-Giannoni and Odell, 2001 as cited in Hayes et al., 2019). In 
U.S. waters, the species has an increasing presence in the coastal 
waters between Maine and Florida. Hooded seals in the U.S. are 
considered members of the western North Atlantic stock and generally 
occur in New England waters from January through May and further south 
off the southeast U.S. coast and in the Caribbean in the summer and 
fall seasons (McAlpine et al. 1999; Harris et al. 2001; and Mignucci-
Giannoni and Odell, 2001 as cited in Hayes et al., 2019).
    Hooded seal occurrences in Rhode Island are predominantly from 
stranding records (approximately 99 percent). They are rare in summer 
and fall but most common in the area during spring and winter (45 
percent and 36 percent of all records, respectively) (Kenney, 2005; 
Kenny and Vigness-Raposa, 2010). Hooded seal strandings are broadly 
distributed across ocean-facing beaches in Rhode Island and they 
occasionally occur well up rivers, but less often than harp seals. 
Hooded seals have been recorded in Narragansett Bay but are considered 
occasional visitors and are expected to be the least encountered seal 
species in the bay (RICRMC, 2010).

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. 
There are no active UME investigations for species affected in the 
project area.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et al. 
1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 4.

                  Table 4--Marine Mammal Hearing Groups
                              [NMFS, 2018]
------------------------------------------------------------------------
                                               Generalized hearing range
                Hearing group                              *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales).  7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins,        150 Hz to 160 kHz.
 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) (true       50 Hz to 86 kHz.
 seals).
Otariid pinnipeds (OW) (underwater) (sea       60 Hz to 39 kHz.
 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. 
Seven marine mammal species (three cetacean and four phocid pinniped 
species) have the reasonable potential to co-occur with the proposed 
construction activities. Please refer to Table 3. Of the cetacean 
species that may be present, two are classified as a mid-frequency 
cetacean (i.e., dolphins), and one is classified as a high-frequency 
cetacean (i.e., harbor porpoise).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated

[[Page 56866]]

Take section, and the Proposed Mitigation section, to draw conclusions 
regarding the likely impacts of these activities on the reproductive 
success or survivorship of individuals and how those impacts on 
individuals are likely to impact marine mammal species or stocks.
    Acoustic effects on marine mammals during the specified activity 
can occur from vibratory and impact pile driving. The effects of 
underwater noise from the Navy's proposed activities have the potential 
to result in Level A and Level B harassment of marine mammals in the 
action area.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
background sound in a given place and is usually a composite of sound 
from many sources both near and far. The sound level of an area is 
defined by the total acoustical energy being generated by known and 
unknown sources. These sources may include physical (e.g., waves, wind, 
precipitation, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ambient sound--depends not 
only on the source levels (as determined by current weather conditions 
and levels of biological and shipping activity) but also on the ability 
of sound to propagate through the environment. In turn, sound 
propagation is dependent on the spatially and temporally varying 
properties of the water column and sea floor, and is frequency-
dependent. As a result of the dependence on a large number of varying 
factors, ambient sound levels can be expected to vary widely over both 
coarse and fine spatial and temporal scales. Sound levels at a given 
frequency and location can vary by 10-20 dB from day to day (Richardson 
et al. 1995). The result is that, depending on the source type and its 
intensity, sound from the specified activity may be a negligible 
addition to the local environment or could form a distinctive signal 
that may affect marine mammals.
    In-water construction activities associated with the project would 
include impact pile driving and vibratory pile driving. The sounds 
produced by these activities fall into one of two general sound types: 
Impulsive and non-impulsive. Impulsive sounds (e.g., explosions, 
gunshots, sonic booms, impact pile driving) are typically transient, 
brief (less than 1 second), broadband, and consist of high peak sound 
pressure with rapid rise time and rapid decay (ANSI 1986; NIOSH 1998; 
ANSI 2005; NMFS 2018a). Non-impulsive sounds (e.g. aircraft, machinery 
operations such as drilling or dredging, vibratory pile driving, and 
active sonar systems) can be broadband, narrowband or tonal, brief or 
prolonged (continuous or intermittent), and typically do not have the 
high peak sound pressure with raid rise/decay time that impulsive 
sounds do (ANSI 1995; NIOSH 1998; NMFS 2018a). The distinction between 
these two sound types is important because they have differing 
potential to cause physical effects, particularly with regard to 
hearing (e.g., Ward 1997 in Southall et al. 2007).
    Two types of pile hammers would be used on this project: Impact and 
vibratory. Impact hammers operate by repeatedly dropping a heavy piston 
onto a pile to drive the pile into the substrate. Sound generated by 
impact hammers is characterized by rapid rise times and high peak 
levels, a potentially injurious combination (Hastings and Popper 2005). 
Vibratory hammers install piles by vibrating them and allowing the 
weight of the hammer to push them into the sediment. Vibratory hammers 
produce significantly less sound than impact hammers. Peak sound 
pressure levels (SPLs) may be 180 dB or greater, but are generally 10 
to 20 dB lower than SPLs generated during impact pile driving of the 
same-sized pile (Oestman et al. 2009). Rise time is slower, reducing 
the probability and severity of injury, and sound energy is distributed 
over a greater amount of time (Nedwell and Edwards 2002; Carlson et al. 
2005).
    The likely or possible impacts of the Navy's proposed activity on 
marine mammals could involve both non-acoustic and acoustic stressors. 
Potential non-acoustic stressors could result from the physical 
presence of the equipment and personnel. However, any impacts to marine 
mammals are expected to primarily be acoustic in nature. Acoustic 
stressors include effects of heavy equipment operation during pile 
driving.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile driving is the primary means by which marine 
mammals may be harassed from the Navy's specified activity. In general, 
animals exposed to natural or anthropogenic sound may experience 
physical and psychological effects, ranging in magnitude from none to 
severe (Southall et al. 2007). In general, exposure to pile driving 
noise has the potential to result in auditory threshold shifts and 
behavioral reactions (e.g., avoidance, temporary cessation of foraging 
and vocalizing, changes in dive behavior). Exposure to anthropogenic 
noise can also lead to non-observable physiological responses such an 
increase in stress hormones. Additional noise in a marine mammal's 
habitat can mask acoustic cues used by marine mammals to carry out 
daily functions such as communication and predator and prey detection. 
The effects of pile driving noise on marine mammals are dependent on 
several factors, including, but not limited to, sound type (e.g., 
impulsive vs. non-impulsive), the species, age and sex class (e.g., 
adult male vs. mom with calf), duration of exposure, the distance 
between the pile and the animal, received levels, behavior at time of 
exposure, and previous history with exposure (Wartzok et al. 2004; 
Southall et al. 2007). Here we discuss physical auditory effects 
(threshold shifts), followed by behavioral effects and potential 
impacts on habitat.
    NMFS defines a noise-induced threshold shift (TS) as a change, 
usually an increase, in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). The amount of 
threshold shift is customarily expressed in dB. A TS can be permanent 
or temporary. As described in NMFS (2018), there are numerous factors 
to consider when examining the consequence of TS, including, but not 
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), the likelihood an individual would be exposed for a long 
enough duration or to a high enough level to induce a TS, the magnitude 
of the TS, the time to recovery (seconds to minutes or hours to days), 
the frequency range of the exposure (i.e., spectral content), the 
hearing and vocalization frequency range of the exposed species 
relative to the signal's frequency spectrum (i.e., how an animal uses 
sound within the frequency band of the signal; e.g., Kastelein et al. 
2014), and the overlap between the animal and the source (e.g., 
spatial, temporal, and spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals

[[Page 56867]]

indicate that a 40 dB threshold shift approximates PTS onset (see Ward 
et al. 1958, 1959; Ward 1960; Kryter et al. 1966; Miller 1974; Ahroon 
et al. 1996; Henderson et al. 2008). PTS levels for marine mammals are 
estimates, and, with the exception of a single study unintentionally 
inducing PTS in a harbor seal (Kastak et al. 2008), there are no 
empirical data measuring PTS in marine mammals, largely due to the fact 
that, for various ethical reasons, experiments involving anthropogenic 
noise exposure at levels inducing PTS are not typically pursued or 
authorized (NMFS 2018).
    Temporary Threshold Shift (TTS)--TTS is a temporary, reversible 
increase in the threshold of audibility at a specified frequency or 
portion of an individual's hearing range above a previously established 
reference level (NMFS 2018). Based on data from cetacean TTS 
measurements (see Southall et al. 2007), a TTS of 6 dB is considered 
the minimum threshold shift clearly larger than any day-to-day or 
session-to-session variation in a subject's normal hearing ability 
(Schlundt et al. 2000; Finneran et al. 2000, 2002). As described in 
Finneran (2015), marine mammal studies have shown the amount of TTS 
increases with cumulative sound exposure level (SELcum) in an 
accelerating fashion: At low exposures with lower SELcum, the amount of 
TTS is typically small and the growth curves have shallow slopes. At 
exposures with higher SELcum, the growth curves become steeper and 
approach linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during a time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al. 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin, beluga whale (Delphinapterus leucas), harbor 
porpoise, and Yangtze finless porpoise (Neophocoena asiaeorientalis)) 
and five species of pinnipeds exposed to a limited number of sound 
sources (i.e., mostly tones and octave-band noise) in laboratory 
settings (Finneran 2015). TTS was not observed in trained spotted 
(Phoca largha) and ringed (Pusa hispida) seals exposed to impulsive 
noise at levels matching previous predictions of TTS onset (Reichmuth 
et al. 2016). In general, harbor seals and harbor porpoises have a 
lower TTS onset than other measured pinniped or cetacean species 
(Finneran 2015). Additionally, the existing marine mammal TTS data come 
from a limited number of individuals within these species. No data are 
available on noise-induced hearing loss for mysticetes. For summaries 
of data on TTS in marine mammals or for further discussion of TTS onset 
thresholds, please see Southall et al. (2007), Finneran and Jenkins 
(2012), Finneran (2015), and Table 5 in NMFS (2018). Installing piles 
requires a combination of impact pile driving and vibratory pile 
driving. For this project, these activities would not occur at the same 
time and there would be pauses in activities producing the sound during 
each day. Given these pauses and that many marine mammals are likely 
moving through the ensonified area and not remaining for extended 
periods of time, the potential for TS declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
removal also has the potential to behaviorally disturb marine mammals. 
Available studies show wide variation in response to underwater sound; 
therefore, it is difficult to predict specifically how any given sound 
in a particular instance might affect marine mammals perceiving the 
signal. If a marine mammal does react briefly to an underwater sound by 
changing its behavior or moving a small distance, the impacts of the 
change are unlikely to be significant to the individual, let alone the 
stock or population. However, if a sound source displaces marine 
mammals from an important feeding or breeding area for a prolonged 
period, impacts on individuals and populations could be significant 
(e.g., Lusseau and Bejder 2007; Weilgart 2007; NRC 2005).
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, or moving direction and/or speed; 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping); avoidance of areas where sound sources are located. 
Pinnipeds may increase their haulout time, possibly to avoid in-water 
disturbance (Thorson and Reyff 2006). Behavioral responses to sound are 
highly variable and context-specific and any reactions depend on 
numerous intrinsic and extrinsic factors (e.g., species, state of 
maturity, experience, current activity, reproductive state, auditory 
sensitivity, time of day), as well as the interplay between factors 
(e.g., Richardson et al. 1995; Wartzok et al. 2003; Southall et al. 
2007; Weilgart 2007; Archer et al. 2010). Behavioral reactions can vary 
not only among individuals but also within an individual, depending on 
previous experience with a sound source, context, and numerous other 
factors (Ellison et al. 2012), and can vary depending on 
characteristics associated with the sound source (e.g., whether it is 
moving or stationary, number of sources, distance from the source). In 
general, pinnipeds seem more tolerant of, or at least habituate more 
quickly to, potentially disturbing underwater sound than do cetaceans, 
and generally seem to be less responsive to exposure to industrial 
sound than most cetaceans. Please see Appendices B-C of Southall et al. 
(2007) for a review of studies involving marine mammal behavioral 
responses to sound.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al. 
2001; Nowacek et al. 2004; Madsen et al. 2006; Yazvenko et al. 2007). A 
determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    Stress responses--An animal's perception of a threat may be 
sufficient to trigger stress responses consisting of some combination 
of behavioral

[[Page 56868]]

responses, autonomic nervous system responses, neuroendocrine 
responses, or immune responses (e.g., Seyle 1950; Moberg 2000). In many 
cases, an animal's first and sometimes most economical (in terms of 
energetic costs) response is behavioral avoidance of the potential 
stressor. Autonomic nervous system responses to stress typically 
involve changes in heart rate, blood pressure, and gastrointestinal 
activity. These responses have a relatively short duration and may or 
may not have a significant long-term effect on an animal's fitness.
    Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that 
are affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction, altered metabolism, reduced immune 
competence, and behavioral disturbance (e.g., Moberg 1987; Blecha 
2000). Increases in the circulation of glucocorticoids are also equated 
with stress (Romano et al. 2004).
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and distress is the cost of the 
response. During a stress response, an animal uses glycogen stores that 
can be quickly replenished once the stress is alleviated. In such 
circumstances, the cost of the stress response would not pose serious 
fitness consequences. However, when an animal does not have sufficient 
energy reserves to satisfy the energetic costs of a stress response, 
energy resources must be diverted from other functions. This is a state 
of distress, and it will last until the animal replenishes its 
energetic reserves sufficient to restore normal function.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well studied through 
controlled experiments and for both laboratory and free-ranging animals 
(e.g., Holberton et al. 1996; Hood et al. 1998; Jessop et al. 2003; 
Krausman et al. 2004; Lankford et al. 2005). Stress responses due to 
exposure to anthropogenic sounds or other stressors and their effects 
on marine mammals have also been reviewed (Fair and Becker 2000; Romano 
et al. 2002b) and, more rarely, studied in wild populations (e.g., 
Romano et al. 2002a). For example, Rolland et al. (2012) found that 
noise reduction from reduced ship traffic in the Bay of Fundy was 
associated with decreased stress in North Atlantic right whales. These 
and other studies lead to a reasonable expectation that some marine 
mammals will experience physiological stress responses upon exposure to 
acoustic stressors and that it is possible that some of these stress 
responses would be classified as distress. In addition, any animal 
experiencing TTS would likely also experience stress responses (NRC, 
2003), however distress is an unlikely result of this project, based on 
observations of marine mammals during previous, similar projects in the 
area.
    Masking--Sound can disrupt behavior through masking, or interfering 
with, an animal's ability to detect, recognize, or discriminate between 
acoustic signals of interest (e.g., those used for intraspecific 
communication and social interactions, prey detection, predator 
avoidance, navigation) (Richardson et al. 1995). Masking occurs when 
the receipt of a sound is interfered with by another coincident sound 
at similar frequencies and at similar or higher intensity, and may 
occur whether the sound is natural (e.g., snapping shrimp, wind, waves, 
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar, 
seismic exploration) in origin. The ability of a noise source to mask 
biologically important sounds depends on the characteristics of both 
the noise source and the signal of interest (e.g., signal-to-noise 
ratio, temporal variability, direction), in relation to each other and 
to an animal's hearing abilities (e.g., sensitivity, frequency range, 
critical ratios, frequency discrimination, directional discrimination, 
age or TTS hearing loss), and existing ambient noise and propagation 
conditions. Masking of natural sounds can result when human activities 
produce high levels of background sound at frequencies important to 
marine mammals. Conversely, if the background level of underwater sound 
is high (e.g., on a day with strong wind and high waves), an 
anthropogenic sound source would not be detectable as far away as would 
be possible under quieter conditions and would itself be masked.
    Airborne Acoustic Effects--Although pinnipeds are known to haul out 
regularly in Narraganset Bay and some in the vicinity of the project 
area, we believe that incidents of take resulting solely from airborne 
sound are unlikely. There is a possibility that an animal could surface 
in-water, but with head out, within the area in which airborne sound 
exceeds relevant thresholds and thereby be exposed to levels of 
airborne sound that NMFS associates with harassment, but any such 
occurrence would likely be accounted for in our estimation of 
incidental take from underwater sound. Therefore, authorization of 
incidental take resulting from airborne sound for pinnipeds is not 
warranted, and airborne sound is not discussed further here. Cetaceans 
are not expected to be exposed to airborne sounds that would result in 
harassment as defined under the MMPA.

Marine Mammal Habitat Effects

    The Navy's construction activities could have localized, temporary 
impacts on marine mammal habitat by increasing in-water sound pressure 
levels and slightly decreasing water quality. Construction activities 
are of short duration and would likely have temporary impacts on marine 
mammal habitat through increases in underwater sound. Increased noise 
levels may affect acoustic habitat (see masking discussion above) and 
adversely affect marine mammal prey in the vicinity of the project area 
(see discussion below). During impact and vibratory pile driving, 
elevated levels of underwater noise would ensonify the project area 
where both fish and mammals may occur and could affect foraging 
success. Additionally, marine mammals may avoid the area during 
construction, however, displacement due to noise is expected to be 
temporary and is not expected to result in long-term effects to the 
individuals or populations.
    A temporary and localized increase in turbidity near the seafloor 
would occur in the immediate area surrounding the area where piles are 
installed. The sediments on the sea floor will be disturbed during pile 
driving; however, suspension will be brief and localized and is 
unlikely to measurably affect marine mammals or their prey in the area. 
In general, turbidity associated with pile installation is localized to 
about a 25-ft (7.6-m) radius around the pile (Everitt et al. 1980). 
Cetaceans are not expected to be close enough to the pile driving areas 
to experience effects of turbidity, and any pinnipeds could avoid 
localized areas of turbidity. Therefore, we expect the impact from 
increased turbidity levels to be discountable to marine mammals and do 
not discuss it further.

In-Water Construction Effects on Potential Foraging Habitat

    The proposed activities would not result in permanent impacts to 
habitats used directly by marine mammals except for the actual 
footprint of the project. The total seafloor area affected by pile 
installation is a very small area compared to the vast foraging area

[[Page 56869]]

available to marine mammals in the surrounding area.
    Avoidance by potential prey (i.e., fish) of the immediate area due 
to the temporary loss of this foraging habitat is also possible. The 
duration of fish avoidance of this area after pile driving stops is 
unknown, but we anticipate a rapid return to normal recruitment, 
distribution and behavior. Any behavioral avoidance by fish of the 
disturbed area would still leave large areas of fish and marine mammal 
foraging habitat in the nearby vicinity in the project area.

Effects on Potential Prey

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

Estimated Take

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

Acoustic Thresholds

    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 (e.g., frequency, predictability, duty cycle), the environment 
(e.g., bathymetry), and the receiving animals (hearing, motivation, 
experience, demography, behavioral context) and can be difficult to 
predict (Southall et al. 2007, Ellison et al. 2012). Based on what the 
available

[[Page 56870]]

science indicates and the practical need to use a threshold based on a 
factor that is both predictable and measurable for most activities, 
NMFS uses a generalized acoustic threshold based on received level to 
estimate the onset of behavioral harassment. NMFS predicts that marine 
mammals are likely to be behaviorally harassed in a manner we consider 
Level B harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 [mu]Pa (rms) (reference pressure 
microPascal, root mean square) for continuous (e.g., vibratory pile-
driving, drilling) and above 160 dB re 1 [mu]Pa (rms) for non-explosive 
impulsive (e.g., seismic airguns) or intermittent (e.g., scientific 
sonar) sources.
    The Navy's construction includes the use of continuous (vibratory 
pile driving) and impulsive (impact pile driving) sources, and 
therefore the level of 120 and 160 dB re 1 [mu]Pa (rms) is 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. The 
technical guidance identifies the received levels, or thresholds, above 
which individual marine mammals are predicted to experience changes in 
their hearing sensitivity for all underwater anthropogenic sound 
sources, and reflects the best available science on the potential for 
noise to affect auditory sensitivity. The technical guidance does this 
by identifying threshholds in the follow manner:
    [ssquf] Dividing sound sources into two groups (i.e., impulsive and 
non-impulsive) based on their potential to affect hearing sensitivity;
    [ssquf] Choosing metrics that best address the impacts of noise on 
hearing sensitivity, i.e., sound pressure level (peak SPL) and sound 
exposure level (SEL) (also accounting for duration of exposure); and
    [ssquf] Dividing marine mammals into hearing groups and developing 
auditory weighting functions based on the science supporting the fact 
that not all marine mammals hear and use sound in the same manner.
    These thresholds were developed by compiling and synthesizing the 
best available science, and are provided in Table 5 below. The 
references, analysis, and methodology used in the development of the 
thresholds are described in NMFS 2018 Technical Guidance, which may be 
accessed at https://www.fisheries.noaa.gov/national/marine-mammal-protection.
    The Navy's proposed construction includes the use of impulsive 
(impact pile driving) and non-impulsive (vibratory pile driving) 
sources.

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

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels transmission loss 
coefficient.

Sound Propagation

    Transmission loss (TL) is the decrease in acoustic intensity as an 
acoustic pressure wave propagates out from a source. TL parameters vary 
with frequency, temperature, sea conditions, current, source and 
receiver depth, water depth, water chemistry, and bottom composition 
and topography. The general formula for underwater TL is:

TL = B * log10(R1/R2),

where

B = transmission loss coefficient (assumed to be 15)
R1 = the distance of the modeled SPL from the driven 
pile, and
R2 = the distance from the driven pile of the initial 
measurement.
    This formula neglects loss due to scattering and absorption, which 
is assumed to be zero here. The degree to which underwater sound 
propagates away from a sound source is dependent on a variety of 
factors, most notably the water bathymetry and presence or absence of 
reflective or absorptive conditions, including in-water structures and 
sediments. Spherical spreading occurs in a perfectly unobstructed 
(free-field) environment not limited by depth or water surface, 
resulting in a 6 dB reduction in sound level for each doubling of 
distance from the source (20*log(range)). Cylindrical spreading occurs 
in an environment in which sound propagation is bounded by the water 
surface and sea bottom, resulting in a reduction of 3 dB in sound level 
for each doubling of distance from the source (10*log(range)). As is 
common practice in coastal waters, here we assume practical spreading 
(4.5 dB reduction in sound level for each doubling of distance). 
Practical spreading is a compromise that is often used under conditions 
where water depth increases as the receiver moves away from the 
shoreline, resulting in an

[[Page 56871]]

expected propagation environment that would lie between spherical and 
cylindrical spreading loss conditions. Practical spreading was used to 
determine sound propagation for this project.

Sound source levels

    The intensity of pile driving sounds is greatly influenced by 
factors such as the type of piles, hammers, and the physical 
environment in which the activity takes place. There are sound source 
level (SSL) measurements available for certain pile types and sizes 
from the similar environments from other Navy pile driving projects 
that were evaluated and used as proxy sound source levels to determine 
reasonable sound source levels likely to result from the pile driving 
and removal activities (Table 6). Some of the proxy source levels are 
expected to be conservative, as the values are from larger pile sizes.

           Table 6--Underwater Noise Sound Source Levels Modeled for Impact and Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
                                                                   Sound pressure levels (SPL) or sound exposure
                                                                           level (SEL) at 10 m distance
            Pile size, type                      Method          -----------------------------------------------
                                                                     Peak SPL         RMS SPL          SEL L
----------------------------------------------------------------------------------------------------------------
42-in Diameter Steel Pipe \1\.........  Impact..................             211             196             181
30-in Diameter Steel Pipe \2\.........  Impact..................             211             196             181
14-in Steel H-pile \3\................  Vibratory...............              NA             158             158
31.5-in Z-shaped Steel Sheet \4\......  Impact..................             211             196             181
31.5-in Z-shaped Steel Sheet \5\......  Vibratory...............              NA             163             163
22.5-in Z-shaped Steel Sheet \3\......  Impact..................             205             190             180
22.5-in Z-shaped Steel Sheet \5\......  Vibratory...............              NA             163             163
----------------------------------------------------------------------------------------------------------------
Legend: All sound pressure levels (SPLs) are unattenuated; dB = decibels; rms = root mean square, SEL = sound
  exposure level; NA = Not applicable; NR = Not reported.
Notes:
\1\ = Navy pers comm. 2021.
\2\ = Navy San Diego Bay Acoustic Compendium (NAVFAC SW 2020).
\3\ = Caltrans 2015.
\4\ = A proxy value for 31-in sheet piles could not be found for impact driving so the proxy for a 30-in steel
  pipe pile has been used from NAVFAC SW (2020). This value was also used for Z-shaped steel sheets for the
  Navy's Dry Dock 1 Modification and Expansion, Portsmouth Naval Shipyard, Kittery, Maine 2021 IHA (86 FR 14598;
  March 17, 2021).
\5\ = For vibratory driving of 31-in sheet piles and 22.5-in Z-shaped steel sheet piles, 163 dB SPL was used
  based on measurements conducted by the Naval Facilities Engineering Command Mid-Atlantic (NAVFAC Mid-Atlantic)
  in the Technical Memorandum Nearshore Marine Mammal Surveys, Portsmouth Naval Shipyard (2018).

    For 42-in steel piles, a SSL of 181 db SEL was used for impact 
driving and is similar to SSL of 180 dB SEL for 36-in piles in CALTRANS 
(2015). There are no SSL values for 42-in piles in CALTRANS, the 
nearest values are for 36-in and 60-in steel pipe piles. For 30-in 
steel pipe piles, a SSL of 181 dB SEL was used for impact pile driving 
as a proxy from the Navy's San Diego Bay Acoustic Compendium (NAVFAC SW 
2020) (the median value from the greatest sound levels recorded for 30-
in steel piles). The SSL used for 30-in steel piles during impact pile 
driving is also more conservative than the SSL of 177 dB SEL for 30-in 
steel piles in CALTRANS (2015). For 31.5-in sheet piles, a SSL of 181 
dB SEL was used for impact pile driving as a proxy from 30-in steel 
pipe piles (NAVFAC SW 2020), which is also slightly more conservative 
than a SSL of 180 dB SEL for 24-in piles in CALTRANS (2015) (no larger 
sheet piles are described in CALTRANS 2015). During vibratory pile 
driving of 31.5-in sheet piles, the Navy used a SSL of 163 dB SPL, 
which is also more conservative than a SSL of 160 dB SPL for 24-in 
sheet piles in CALTRANS (2015) (no large sheet piles are described in 
CALTRANS 2015). For 22.5-in Z-shaped steel sheet piles, a SSL of 180 dB 
SEL was used for impact pile driving and is also equivalent to 24-in 
sheet piles in CALTRANS (2015). During vibratory pile driving, a SSL of 
163 dB SPL is a proxy from NAVFAC Mid-Atlantic (2018) and is also more 
conservative than 24-in sheet piles in CALTRANS (2015) where the SSL is 
160 dB SPL for 24-in sheet piles (no larger sheet piles are described 
in CALTRANS (2015). For 14-in steel H-piles, a SSL of 158 dB SPL was 
used from CALTRANS (2015).
Level A Harassment
    In conjunction with the NMFS Technical Guidance (2018), in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, NMFS developed a User Spreadsheet that includes 
tools to help predict a simple isopleth that can be used in conjunction 
with marine mammal density or occurrence to help predict takes. We note 
that, because of some of the assumptions included in the methods used 
for these tools, we anticipate that isopleths produced are typically 
going to be overestimates of some degree, which may result in some 
degree of overestimation of Level A harassment take. However, these 
tools offer the best way to predict appropriate isopleths when more 
sophisticated 3D modeling methods are not available, and NMFS continues 
to develop ways to quantitatively refine these tools, and will 
qualitatively address the output where appropriate. For stationary 
sources (such as from impact and vibratory pile driving), the NMFS User 
Spreadsheet (2020) predicts the closest distance at which, if a marine 
mammal remained at that distance the whole duration of the activity, it 
would not incur PTS. Inputs used in the User Spreadsheet (Tables 7 and 
8), and the resulting isopleths are reported below (Table 9).

[[Page 56872]]



  Table 7--NMFS Technical Guidance (2020) User Spreadsheet Input To Calculate PTS Isopleths for Vibratory Pile
                                                     Driving
        [User spreadsheet input--Vibratory Pile Driving Spreadsheet Tab A.1 Vibratory Pile Driving Used.]
----------------------------------------------------------------------------------------------------------------
                                                                                    22.5-in Z-      31.5-in Z-
                                                                  14-in steel H-   shaped sheet    shaped sheet
                                                                       pile            piles           piles
----------------------------------------------------------------------------------------------------------------
Source Level (RMS SPL)..........................................             158             163             163
Weighting Factor Adjustment (kHz)...............................             2.5             2.5             2.5
Number of piles within 24-hr period.............................              12              10               8
Duration to drive a single pile (min)...........................              10              13              13
Propagation (xLogR).............................................              15              15              15
Distance of source level measurement (m)........................              10              10              10
----------------------------------------------------------------------------------------------------------------


    Table 8--NMFS Technical Guidance (2020) User Spreadsheet Input To Calculate PTS Isopleths for Impact Pile
                                                     Driving
           [User spreadsheet input--Impact Pile Driving Spreadsheet Tab E.1 Impact Pile Driving Used.]
----------------------------------------------------------------------------------------------------------------
                                                  22-in Z-shaped    31.5-in Z-
                                                       piles       shaped piles     30-in pile      42-in pile
----------------------------------------------------------------------------------------------------------------
Source Level (Single Strike/shot SEL)...........             180             181             181             181
Weighting Factor Adjustment (kHz)...............               2               2               2               2
Number of strikes per pile......................             530             530             530             530
Number of piles per day.........................              10               8               2               4
Propagation (xLogR).............................              15              15              15              15
Distance of source level measurement (m)........              10              10              10              10
----------------------------------------------------------------------------------------------------------------


                     Table 9--NMFS Technical Guidance (2020) User Spreadsheet Outputs To Calculate Level A Harassment PTS Isopleths
                                                                [User spreadsheet output]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                         PTS isopleths (m)
                                                                         -------------------------------------------------------------------------------
                                                                                                        Level A harassment
               Activity                    Sound source level at 10 m    -------------------------------------------------------------------------------
                                                                                                               High-
                                                                           Low-frequency   Mid-frequency     frequency        Phocid          Otariid
                                                                             cetaceans       cetaceans       cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Vibratory Pile Driving/Removal
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-inch H-pile........................  158 SPL.........................             6.8             0.6            10.1             4.2             0.3
22.5-in Z-shaped sheet piles..........  163 SPL.........................            15.5             1.4            23.0             9.4             0.7
31.5-in Z-shaped sheet piles..........  163 SPL.........................            13.4             1.2            19.8             8.1             0.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Impact Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
22.5-in Z-shaped sheet piles..........  180 SEL/190 SPL.................         1,915.4            68.1         2,281.5         1,025.0            74.6
31.5-in Z-shaped sheet piles..........  181 SEL/196 SPL.................         1,942.5            68.4         2,292.4         1,029.9            75.0
30-in pile............................  181 SEL/196 SPL.................           763.7            27.2           909.7           408.7            29.8
42-in pile............................  181 SEL/196 SPL.................           1,212            43.1         1,444.1           648.8            47.2
--------------------------------------------------------------------------------------------------------------------------------------------------------

Level B Harassment
    Utilizing the practical spreading model, NMFS determined underwater 
noise will fall below the behavioral effects threshold of 120 dB rms 
for marine mammals at the distances shown in Table 10 for vibratory 
pile driving. With these radial distances, the largest Level B 
harassment zone calculated was 7,356 m for sheet piles. However, this 
distance would be truncated due to the presence of intersecting land 
masses. For calculating the Level B harassment zone for impact driving, 
the practical spreading loss model was used with a behavioral threshold 
of 160 dB rms. The maximum radial distance of the Level B harassment 
zone for impact piling equaled 2,512 m for 30-in piles, 42-in piles and 
31.5-in sheet piles. Table 10 below provides all Level B harassment 
radial distances (m) and ensonified areas (km\2\) during the Navy's 
proposed activities.

[[Page 56873]]



                    Table 10--Distances to Relevant Behavioral Isopleths and Ensonified Areas
----------------------------------------------------------------------------------------------------------------
                                                                                                    Level B
             Year (section)                       Activity            Received level at 10 m    harassment zone
                                                                                                  (m/km\2\) *
----------------------------------------------------------------------------------------------------------------
                                             Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
Year 1 (S45)...........................  14-in H-piles............  158 SPL..................  3,415 m/5.6 km\2\
Year 2 (S366), Year 2 (Pier 1).........  14-in H-piles............  158 SPL..................  3,415 m/5.8 km\2\
Year 3 (LNG)...........................  14-in H-piles............  158 SPL..................  3,415 m/5.8 km\2\
Year 4 (S499/Pier 2)...................  14-in H-piles............  158 SPL..................  3,415 m/5.7 km\2\
Year 1 (S45)...........................  22.5-in Z-shaped sheet     163 SPL..................  7,356 m/7.9 km\2\
                                          piles.
Year 2 (S366), Year 2 (Pier 1).........  22.5-in Z-shaped sheet     163 SPL..................  7,356 m/8.3 km\2\
                                          piles.
Year 3 (LNG)...........................  22.5-in Z-shaped sheet     163 SPL..................  7,356 m/7.5 km\2\
                                          piles.
Year 4 (S499/Pier 2)...................  22.5-in Z-shaped sheet     163 SPL..................  7,356 m/7.5 km\2\
                                          piles.
Year 4 (S499/Pier 2)...................  31.5-in Z-shaped sheet     163 SPL..................  7,356 m/9.5.km\2\
                                          piles.
----------------------------------------------------------------------------------------------------------------
                                               Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
Year 1 (S45)...........................  22.5-in Z-shaped sheet     180 SEL/190 SPL..........  1,000 m/1.1 km\2\
                                          piles.
Year 2 (S366), Year 2 (Pier 1).........  22.5-in Z-shaped sheet     180 SEL/190 SPL..........  1,000 m/1.3 km\2\
                                          piles.
Year 3 (LNG)...........................  22.5-in Z-shaped sheet     180 SEL/190 SPL..........  1,000 m/0.7 km\2\
                                          piles.
Year 4 (S499/Pier 2)...................  31.5-in Z-shaped sheet     181 SEL/196 SPL..........  2,512 m/3.8 km\2\
                                          piles.
Year 1 (S45)...........................  30-in piles..............  181 SEL/196 SPL..........  2,512 m/3.8 km\2\
Year 2 (S366)..........................  30-in piles..............  181 SEL/196 SPL..........  2,512 m/4.0 km\2\
Year 4 (S499/Pier 2)...................  42-in piles..............  181 SEL/196 SPL..........  2,512 m/3.8 km\2\
----------------------------------------------------------------------------------------------------------------
* Note: Distances to the Level B harassment zone may vary slightly of the same pile size, due to the section of
  work being conducted and how the produced sound would be directed (see Figures 6-1 through 6-4 of the Navy's
  application).

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. Potential exposures to impact pile and vibratory pile 
driving noise for each acoustic threshold were estimated using marine 
mammal density estimates (N) from the Navy Marine Species Density 
Database NMSDD (Navy 2017) for which data of monthly densities of 
species were evaluated in terms of minimum, maximum, and average annual 
densities within Narragansett Bay and multiplied by the zone of 
influence (ZOI) and the maximum days of pile driving (take estimate = N 
x ZOI x days of pile driving). The pile type, size, and installation 
method that produce the largest ZOI were used to estimate exposure of 
marine mammals to noise impacts. We describe how the information 
provided above is brought together to produce a quantitative take 
estimate in the species sections below.
Atlantic White-Sided Dolphins
    Atlantic white-sided dolphins occur seasonally, occurring primarily 
along the continental shelf with occasional unconfirmed opportunistic 
sightings in Narragansett Bay in fall and winter. The most recent 
observation of a pod of dolphins in Narragansett Bay was in October 
2007 (NUWC Division, 2011). Construction activity could occur at any 
time of year and would be short-term and intermittent. Therefore, the 
average species density was determined to be appropriate for estimating 
takes of Atlantic white-sided dolphin. Based on density data for 
Narragansett Bay (Navy 2017), the average density of Atlantic white-
sided dolphin was determined to be 0.003/km\2\. This density was used 
to estimate abundance of animals that could be present in the area for 
exposure. Using this information, 1 take was calculated for Years 1, 3, 
and 4 and 0 takes in Year 2 (Table 11). However, the annual take by 
Level B harassment proposed for Atlantic white-sided dolphins has been 
increased to the average group size (16) (NAVSEA NUWC 2017) for Years 
1, 3, and 4, because the calculated annual take is below the average 
group size. Therefore, the Navy requested and NMFS proposes 16 takes 
annually in Years 1, 3, and 4 (0 in Year 2) for a total of 48 takes by 
Level B harassment of Atlantic white-sided dolphin (Table 11). No takes 
by Level A harassment of Atlantic white-sided dolphin are anticipated. 
Because this species' regular occurrence is in much deeper waters than 
the extent of the ZOI (Hayes et al., 2019), expected takes of this 
species are extremely low.

        Table 11--Proposed Take for Atlantic White-Sided Dolphin
------------------------------------------------------------------------
                                            Calculated
            Construction year                 Level B     Proposed Level
                                            harassment     B  harassment
------------------------------------------------------------------------
Year 1 (S45)............................               1              16
Year 2 (S366 and Pier 01)...............               0               0
Year 3 (LNG)............................               1              16
Year 4 (S499/Pier 2)....................               1              16
                                         -------------------------------
    Total...............................               3              48
------------------------------------------------------------------------


[[Page 56874]]

Common Dolphin
    Common dolphins are the most likely dolphin species to be spotted 
in Narragansett Bay, and usually occur in late fall or winter (Kenney, 
2013). The most recent sighting of a common dolphin recorded in 
Narragansett Bay was in October of 2016 (Hayes et al., 2019). 
Construction activity could occur at any time of year and would be 
short-term and intermittent. Based on density data for Narragansett Bay 
(NMSDD, Navy, 2017), the average density of common dolphin was 
determined to be 0.011/km\2\. Using this information, 3 takes by Level 
B harassment were calculated for Years 1 and 4, 2 takes for Year 2 and 
6 takes for Year 3 (Table 12). Because the calculated annual take is 
below the average group size, the annual take by Level B harassment 
proposed for common dolphin has been increased to the average group 
size (28) (NAVSEA NUWC 2017). Therefore, the Navy requested and NMFS 
proposes 28 takes annually (with the exception of Year 2, for which it 
was doubled to 56 takes as a conservative approach to account for more 
vibratory and impact pile driving activities that occur during that 
year in two sections (S366 and Pier 1)) for a total of 140 takes by 
Level B harassment of common dolphin (Table 12). No takes by Level A 
harassment of common dolphin are anticipated. Because this species' 
regular occurrence is in much deeper waters than the extent of the ZOI 
(Hayes et al., 2019), takes of this species are expected to be 
extremely low.

               Table 12--Proposed Take for Common Dolphin
------------------------------------------------------------------------
                                            Calculated
            Construction year                 Level B     Proposed Level
                                            harassment     B  harassment
------------------------------------------------------------------------
Year 1 (S45)............................               3              28
Year 2 (S366 and Pier 01)...............               2              56
Year 3 (LNG)............................               6              28
Year 4 (S499/Pier 2)....................               3              28
                                         -------------------------------
    Total...............................              14             140
------------------------------------------------------------------------

Harbor Porpoise
    Harbor porpoise are not common to Narragansett Bay but may occur, 
especially in winter and spring months (Kinney 2013). Harbor porpoise 
is the most stranded cetacean in Rhode Island, with a strong seasonal 
occurrence in the spring. Construction activity could occur at any time 
of year and would be short-term and intermittent. Therefore, the 
average species density was determined to be appropriate for estimating 
takes of harbor porpoise. Based on density data for Narragansett Bay 
(NMSDD, Navy 2017), the average density of harbor porpoise was 
determined to be 0.012/km\2\. Using this information, 4 takes by Level 
B harassment were calculated for Years 1 and 4, 2 takes for Year 2, and 
7 takes for Year 3 (Table 13). Because the calculated take in Year 2 
was less than the group size, the annual take by Level B harassment 
proposed for harbor porpoise has been increased to the average group 
size (3) and multiplied by two for 6 takes (NAVSEA NUWC 2017) as a 
conservative approach to account for more vibratory and impact pile 
driving activities that occur during that year in two sections (S366 
and Pier 1)). Therefore, the Navy requested and NMFS proposes 4 takes 
in Years 1 and 4, 6 takes in Year 2, and 7 takes in Year 3, and a total 
of 21 takes by Level B harassment of harbor porpoise (Table 13). Level 
A harassment could occur during years 1, 3 and 4 (Table 13).

                                   Table 13--Proposed Take for Harbor Porpoise
----------------------------------------------------------------------------------------------------------------
                                                                                    Calculated
                        Construction year                         Proposed Level      Level B     Proposed Level
                                                                   A  harassment    harassment     B  harassment
----------------------------------------------------------------------------------------------------------------
Year 1 (S45)....................................................               1               4               4
Year 2 (S366 and Pier 01).......................................               0               2               6
Year 3 (LNG)....................................................               2               7               7
Year 4 (S499/Pier 2)............................................               1               4               4
                                                                 -----------------------------------------------
    Total.......................................................               4              17              21
----------------------------------------------------------------------------------------------------------------

Harbor Seal
    Harbor seals are the most common seal in Narragansett Bay, which is 
a well-known winter feeding ground for the species (Moll et al., 2017). 
Seals are commonly observed from late September through April (Moll et. 
al., 2017; DeAngelis, 2020). Of the 22 known haulouts within 
Narragansett Bay, The Sisters is the nearest haulout to the project 
area (0.9 mi). Harbor seals are rarely observed at The Sisters haulout 
in the early fall (September-October) but consistent numbers are 
regularly observed in mid-November (0-10 animals). These numbers 
gradually increase with peak numbers in the upper 40s occurring in 
March, typically at low tide (DeAngelis, 2020). The NMSDD (Navy, 2017a) 
models harbor and gray seals as a guild due to the difficulty in 
distinguishing these species at sea. Harbor seal is expected to be the 
most common pinniped in Narragansett Bay with year-round occurrence 
(Kenney and Vigness-Raposa, 2010). Therefore, the maximum species 
density for the harbor-gray seal guild was determined to be appropriate 
for estimating takes of harbor seal. Based on density data for 
Narragansett Bay (Navy, 2017a), the maximum density of seals was 
determined to be 0.623/km\2\. This density value is for all seals 
(harbor and gray seals as a guild); therefore, this density value 
results in some degree of overestimation when applied to harbor seals 
only. The Navy requested and NMFS proposes a high of 25 takes by Level 
A harassment and 353 takes by Level B harassment during Year 3, and a 
low of 13 takes by Level A harassment

[[Page 56875]]

and 138 takes by Level B harassment during Year 2 (Table 14).

                 Table 14--Proposed Take for Harbor Seal
------------------------------------------------------------------------
                                                            Calculated/
            Construction year             Proposed Level  proposed Level
                                           A  harassment   B  harassment
------------------------------------------------------------------------
Year 1 (S45)............................              15             188
Year 2 (S366 and Pier 01)...............              13             138
Year 3 (LNG)............................              25             353
Year 4 (S499/Pier 2)....................              25             221
                                         -------------------------------
    Total...............................              78             900
------------------------------------------------------------------------

Gray Seal
    Based on stranding records, gray seals are seasonally present in 
Rhode Island with the largest populations occurring from February 
through June with a sharp peak in March and April. The NMSDD (Navy, 
2017a) provides combined densities for harbor seal and gray seal (as 
discussed above). Gray seals are the second most likely seal to be 
observed in Rhode Island waters, next to harbor seals, and more of an 
occasional visitor (Kenney, 2020); therefore, the average species 
density for the harbor-gray seal guild was determined to be appropriate 
for determining takes of gray seal. Based on density data for 
Narragansett Bay (Navy, 2017a), the average density of seals was 
determined to be 0.131/km\2\. This density value is for all seals 
(harbor and gray seals as a guild); therefore, it results in some 
degree of overestimation when applied to gray seals only. Calculated 
takes by Level A harassment and Level B harassment may occur each 
construction year with up to 5 takes by Level A harassment and 74 takes 
by Level B harassment during Year 3. Fewer annual takes were calculated 
for Year 2 and 3 by Level A harassment and 28 takes by Level B (Table 
15). Because the calculated annual take is below the average group 
size, the annual take by Level B harassment proposed for gray seal has 
been increased to the average group size (50 gray seals) (NAVSEA NUWC 
2017) and conservatively doubled for Year 1, 2, and 4, during which 
years calculated takes were less than group size. Therefore, the Navy 
requested and NMFS proposes 100 takes of gray seals in Years 1, 2 and 
4, and 74 takes in Year 3, and a total of 374 takes by Level B 
harassment of gray seals. A total of 17 takes of gray seals by Level A 
harassment is also proposed.

                                      Table 15--Proposed Take for Gray Seal
----------------------------------------------------------------------------------------------------------------
                                                                                    Calculated
                        Construction year                         Proposed Level      Level B     Proposed Level
                                                                   A  harassment    harassment     B  harassment
----------------------------------------------------------------------------------------------------------------
Year 1 (S45)....................................................               3              40             100
Year 2 (S366 and Pier 01).......................................               3              28             100
Year 3 (LNG)....................................................               5              74              74
Year 4 (S499/Pier 2)............................................               6              41             100
                                                                 -----------------------------------------------
    Total.......................................................              17             183             374
----------------------------------------------------------------------------------------------------------------

Harp Seal
    Harp seals may be present in the project vicinity January through 
May. In general, harp seals are much rarer than the harbor seal and 
gray seal in Narragansett Bay and are rarely observed in the bay 
(Kenney, 2015). Therefore, the minimum species density was determined 
to be appropriate for determining takes of harp seal. Based on density 
data for Narragansett Bay obtained from the NMSDD (Navy 2017), the 
minimum density of harp seal was determined to be 0.050/km\2\. The Navy 
requested and NMFS proposes that 2 takes by Level A harassment could 
occur in Year 3, and 1 take by Level A harassment in Years 1, 2, and 4, 
for a total of 5 takes (Table 16). Calculated takes by Level B 
harassment range from 11 to 29 and total 72 takes over the project 
(Table 16).

                  Table 16--Proposed Take for Harp Seal
------------------------------------------------------------------------
                                                            Calculated/
            Construction year             Proposed Level  proposed Level
                                           A  harassment   B  harassment
------------------------------------------------------------------------
Year 1 (S45)............................               1              16
Year 2 (S366 and Pier 1)................               1              11
Year 3 (LNG)............................               2              29
Year 4 (S499/Pier 2)....................               2              18
                                         -------------------------------
    Total...............................               6              74
------------------------------------------------------------------------


[[Page 56876]]

Hooded Seal
    Hooded seals may be present in the project vicinity from January 
through May, although their exact seasonal densities are unknown. In 
general, hooded seals are much rarer than the harbor seal and gray seal 
in Narragansett Bay and are rarely observed in the Bay (Kenney, 2005). 
Based on density data for Narragansett Bay obtained from the NMSDD, the 
minimum density of hooded seal was determined to be 0.001/km\2\. Hooded 
seals have the potential to occur but are considered the least likely 
seal to be present in Narragansett Bay. No Level A (PTS onset) or Level 
B (behavioral) takes are anticipated during any construction year. 
However, in order to guard against unauthorized take, the Navy is 
requesting and NMFS is proposing 1 Level B (behavioral) take of hooded 
seal per month of construction when this species may occur (Jan through 
May) for each construction year for a total of 20 takes by Level B 
harassment (Table 17). No take by Level A harassment is anticipated or 
proposed for authorization for this species.

                 Table 17--Proposed Take for Hooded Seal
------------------------------------------------------------------------
                                                          Proposed Level
                    Construction year                      B  harassment
------------------------------------------------------------------------
Year 1 (S45)............................................               5
Year 2 (S366 and Pier 1)................................               5
Year 3 (LNG)............................................               5
Year 4 (S499/Pier 2)....................................               5
                                                         ---------------
    Total...............................................              20
------------------------------------------------------------------------

    Table 18 below summarizes the proposed authorized take for all the 
species described above as a percentage of stock abundance.

                           Table 18--Take Estimates as a Percentage of Stock Abundance
----------------------------------------------------------------------------------------------------------------
                                                               Level A         Level B
              Species                   Stock  (NEST)        harassment      harassment       Percent of stock
----------------------------------------------------------------------------------------------------------------
Atlantic White-sided Dolphin......  Western North                       0              48  Less than 1 percent.
                                     Atlantic (93,233).
Common Dolphin....................  Western North                       0             140  Less than 1 percent.
                                     Atlantic (172,974).
Harbor Porpoise...................  Gulf of Maine/Bay of                4              21  Less than 1 percent.
                                     Fundy (95,543).
Harbor Seal.......................  Western North                      78             900  Less than 2 percent.
                                     Atlantic (75,834).
Gray Seal.........................  Western North                      17             374  Less than 1 percent.
                                     Atlantic (451,131).
Harp Seal.........................  Western North                       6              74  Less than 1 percent.
                                     Atlantic (unknown).
Hooded Seal.......................  Western North                       0              20  Less than 1 percent.
                                     Atlantic (unknown).
----------------------------------------------------------------------------------------------------------------

Proposed Mitigation

    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 adverse 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, we carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned), and;
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    The following mitigation measures are proposed for the Navy's in-
water construction activities.

General

    The Navy will follow mitigation procedures as described below. In 
general, if poor environmental conditions restrict full visibility of 
the shutdown zone, pile driving activities would be delayed.

Training

    The Navy will ensure that construction supervisors and crews, the 
monitoring team, and relevant Navy staff are trained and prior to the 
start of construction activity subject to this rule, so that 
responsibilities, communication procedures, monitoring protocols, and 
operational procedures are clearly understood. New personnel joining 
during the project will be trained prior to commencing work.

Avoiding Direct Physical Interaction

    The Navy will avoid direct physical interaction with marine mammals 
during construction activity. If a marine mammal comes within 10 m of 
such activity, operations will cease and vessels will reduce speed to 
the minimum level required to maintain steerage and safe working 
conditions, as necessary to avoid direct physical interaction.

Shutdown Zones

    The Navy will establish shutdown zones for all pile driving 
activities. The purpose of a shutdown zone is generally to define an 
area within which shutdown of the activity would occur upon sighting of 
a marine mammal (or in anticipation of an animal entering the defined 
area). Shutdown zones will vary based on the activity type and marine 
mammal hearing group (Table 19). For those activities with larger Level 
A (PTS onset) harassment zones, the shutdown zone would be limited to 
150 m from the point of noise generation to ensure adequate monitoring 
for each bulkhead section and the remaining area would be considered 
part of the ``disturbance zone.'' A take will be recorded if a marine 
mammal enters the disturbance zone but does not approach or enter the 
shutdown zone. The disturbance zone is the Level B harassment zone and, 
where

[[Page 56877]]

present, the Level A harassment zone (PTS onset) beyond 150 m from the 
point of noise generation (see Figures 6-1 through 6-4 of the Navy's 
application). For activities where the Level A (PTS onset) harassment 
zones are smaller, the disturbance zone would include the entire region 
of influence (ROI) and is the full extent of potential underwater noise 
impact (Level A and Level B calculated harassment zones). Work will be 
allowed to proceed without cessation while marine mammals are in the 
disturbance zone and marine mammal behavior within the disturbance zone 
will be monitored and documented.

              Table 19--Pile Driving Shutdown Zone and Disturbance Zones During Project Activities
----------------------------------------------------------------------------------------------------------------
                                   Installation                   Shut down zone  Shut down zone    Disturbance
            Pile type                 method       Pile diameter   for cetaceans   for pinnipeds       zone
----------------------------------------------------------------------------------------------------------------
Steel pipe......................          Impact           30-in           150 m           150 m         2,500 m
                                          Impact           42-in           150 m            50 m         2,500 m
Steel H.........................       Vibratory           14-in            10 m            10 m             ROI
                                       Vibratory         22.5-in            30 m            10 m             ROI
Z-Shaped Steel Sheet............          Impact         22.5-in           150 m           150 m         2,500 m
                                       Vibratory         31.5-in            20 m            10 m             ROI
                                          Impact         31.5-in           150 m           150 m         2,500 m
----------------------------------------------------------------------------------------------------------------
* ROI = region of influence and is the full extent of potential underwater noise impact (Level A and Level B
  calculated harassment zones).

Soft Start

    The Navy will use soft start techniques when impact pile driving. 
Soft start requires contractors 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 would 
occur. A 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. Soft start is not 
required during vibratory pile driving activities.
    Based on our evaluation of the applicant's proposed measures, NMFS 
has preliminarily determined that the proposed mitigation measures 
provide the 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.

Proposed Monitoring and Reporting

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

Monitoring Zones

    The Navy will conduct monitoring to include the area within the 
Level B harassment zones (areas where SPLs are equal to or exceed the 
160 dB rms threshold for impact driving and the 120 dB rms threshold 
during vibratory pile driving) (see Disturbance Zones in Table 19). 
These disturbance zones provide utility for monitoring conducted for 
mitigation purposes (i.e., shutdown zone monitoring) by establishing 
monitoring protocols for areas adjacent to the shutdown zones. 
Monitoring of the disturbance zones enables observers to be aware of 
and communicate the presence of marine mammals in the project area, but 
outside the shutdown zone, and thus prepare for potential shutdowns of 
activity.

Visual Monitoring

    Monitoring must take place from 30 minutes (min) prior to 
initiation of pile driving activity (i.e., pre-start clearance 
monitoring) through 30 min post-completion of pile driving activity. If 
a marine mammal is observed entering or within the shutdown zones, pile 
driving will be delayed or halted. If pile driving 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 min have passed 
without re-detection of the animal. Pile driving activity will 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 disturbance zone.

[[Page 56878]]

PSO Monitoring Requirements and Locations

    PSOs will be responsible for monitoring, the shutdown zones, the 
disturbance zones and the pre-clearance zones, as well as effectively 
documenting Level A and B harassment take. As described in more detail 
in the Reporting section below, they will also (1) document the 
frequency at which marine mammals are present in the project area, (2) 
document behavior and group composition, (3) record all construction 
activities, and (4) document observed reactions (changes in behavior or 
movement) of marine mammals during each sighting. The PSOs will monitor 
for marine mammals during all in-water pile activities associated with 
the project. The Navy will monitor the project area to the extent 
possible based on the required number of PSOs, required monitoring 
locations, and environmental conditions. Visual monitoring will be 
conducted by, at a minimum, by two PSOs. It is assumed that two to 
three PSOs would be sufficient to monitor the respective ROIs given the 
abundance of suitable vantage points. Any activity that would result in 
threshold exceedance at or more than 1,000 m would require a minimum of 
three PSOs to effectively monitor the entire ROI. However, additional 
monitors may be added if warranted by site conditions and/or the level 
of marine mammal activity in the area. Trained PSOs will be placed at 
the best vantage point(s) practicable such as on nearby breakwaters, 
Gould Island, Coddington Point, or Taylor Point (see Figure 11-1 of the 
Navy's application) to monitor for marine mammals and implement 
shutdown/delay procedures when applicable. The PSOs must record all 
observations of marine mammals, regardless of distance from the pile 
being driven.
    In addition, PSOs will work in shifts lasting no longer than 4 hrs 
with at least a 1-hr break between shifts, and will not perform duties 
as a PSO for more than 12 hrs in a 24[hyphen]hr period (to reduce PSO 
fatigue).
    Monitoring of pile driving will be conducted by qualified, NMFS-
approved PSOs. The Navy shall adhere to the following conditions when 
selecting PSOs:
    [ssquf] PSOs must be independent (i.e., not construction personnel) 
and have no other assigned tasks during monitoring periods;
    [ssquf] At least one PSO must have prior experience performing the 
duties of a PSO during construction activities pursuant to a NMFS-
issued incidental take authorization;
    [ssquf] Other PSOs may substitute other relevant experience, 
education (degree in biological science or related field), or training;
    [ssquf] Where a team of three PSOs are required, a lead observer or 
monitoring coordinator shall be designated. The lead observer must have 
prior experience performing the duties of a PSO during construction 
activity pursuant to a NMFS-issued incidental take authorization; and
    [ssquf] PSOs must be approved by NMFS prior to beginning any 
activity subject to this proposed rule.
    The Navy will ensure that the PSOs have the following additional 
qualifications:
    [ssquf] Visual acuity in both eyes (correction is permissible) 
sufficient for discernment of moving targets at the water's surface 
with ability to estimate target size and distance; use of binoculars 
may be necessary to correctly identify the target;
    [ssquf] Experience and ability to conduct field observations and 
collect data according to assigned protocols;
    [ssquf] Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
    [ssquf] Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
    [ssquf] Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
    [ssquf] 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.

Acoustic Monitoring

    The Navy intends to conduct a sound source verification (SSV) study 
for all pile types and will follow accepted methodological standards to 
achieve their objectives. The Navy will submit an acoustic monitoring 
plan to NMFS for approval prior to the start of construction.

Reporting

    The Navy would submit a draft report to NMFS within 90 workdays of 
the completion of required monitoring for each portion of the project 
as well as a comprehensive summary report at the end of the project. 
The report will detail the monitoring protocol and summarize the data 
recorded during monitoring. Final annual reports (each portion of the 
project and comprehensive) 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 shall be considered final. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments. All draft and final marine 
mammal monitoring reports must be submitted to 
[email protected] and [email protected]. The reports 
must contain the following informational elements, at minimum, (and be 
included in the Marine Mammal Monitoring Plan), including:
    [ssquf] Dates and times (begin and end) of all marine mammal 
monitoring;
    [ssquf] Construction activities occurring during each daily 
observation period, including:
    [cir] How many and what type of piles were driven and by what 
method (e.g., impact or vibratory); and
    [cir] Total duration of driving time for each pile (vibratory 
driving) and number of strikes for each pile (impact driving);
    [ssquf] PSO locations during marine mammal monitoring;
    [ssquf] 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;
    [ssquf] Upon observation of a marine mammal, the following 
information:
    [cir] PSO who sighted the animal and PSO location and activity at 
time of sighting;
    [cir] Time of sighting;
    [cir] Identification of the animal (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;
    [cir] Distance and bearing of each marine mammal observed to the 
pile being driven for each sighting (if pile driving was occurring at 
time of sighting);
    [cir] Estimated number of animals (minimum/maximum/best);
    [cir] Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition, etc.;

[[Page 56879]]

    [cir] Animal's closest point of approach and estimated time spent 
within the harassment zone; and
    [cir] Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses to the activity (e.g., no response 
or changes in behavioral state such as ceasing feeding, changing 
direction, flushing, or breaching);
    [ssquf] Detailed information about implementation of any mitigation 
(e.g., shutdowns and delays), a description of specific actions that 
ensued, and resulting changes in behavior of the animal, if any; and
    [ssquf] All PSO datasheets and/or raw sightings data.

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 must 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. 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 
will not resume their activities until notified by NMFS. The report 
must include the following information:
    [ssquf] Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    [ssquf] Species identification (if known) or description of the 
animal(s) involved;
    [ssquf] Condition of the animal(s) (including carcass condition if 
the animal is dead);
    [ssquf] Observed behaviors of the animal(s), if alive;
    [ssquf] If available, photographs or video footage of the 
animal(s); and
    [ssquf] General circumstances under which the animal was 
discovered.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
taken through harassment, NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration), the context 
of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS' implementing 
regulations (54 FR 40338; September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, ongoing sources of human-caused mortality, or 
ambient noise levels).
    To avoid repetition, this introductory discussion of our analyses 
applies to all of 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 in anticipated 
individual responses to activities, impacts of expected take on the 
population due to differences in population status, or impacts on 
habitat, they are described independently in the analysis below.
    Pile driving 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. 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.
    No serious injury or mortality would be expected even in the 
absence of the proposed mitigation measures. During all impact driving, 
implementation of soft start procedures and monitoring of established 
shutdown zones will be required, significantly reducing the possibility 
of injury. Given sufficient notice through use of soft start (for 
impact driving), marine mammals are expected to move away from an 
irritating sound source prior to it becoming potentially injurious. In 
addition, PSOs will be stationed within the action area whenever pile 
driving activities are underway. Depending on the activity, the Navy 
will employ the use of at least two and up to three PSOs to ensure all 
monitoring and shutdown zones are properly observed. For Atlantic 
white-sided dolphins, common dolphins and hooded seals, no Level A 
harassment is anticipated. Atlantic white-sided dolphin and common 
dolphin are both species in which regular occurrence is in much deeper 
waters than the project area, and, given the small Level A harassment 
zone sizes for mid-frequency cetaceans, we do not anticipate take by 
Level A harassment. For hooded seals, with the absence of any major 
rookeries and only one pinniped haulout (The Sisters) within the 
project area, and being a rare species in Narragansett Bay, we do not 
anticipate any take by Level A harassment.
    The Navy's proposed pile driving activities and associated impacts 
will occur within a limited portion of the confluence of the 
Narraganset Bay area. Exposures to elevated sound levels produced 
during pile driving activities may cause behavioral disturbance of some 
individuals, but they are expected to be mild and temporary. However, 
as described previously, the mitigation and monitoring measures are 
expected to further reduce the likelihood of injury as well as reduce 
behavioral disturbances.
    Effects on individuals that are taken by Level B harassment, as 
enumerated in the Estimated Take section, 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). Most likely, individual 
animals will simply move away from the sound source and be temporarily 
displaced from the areas of pile driving, although even this reaction 
has been observed primarily only in association with impact pile 
driving. The pile driving 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. These 
reactions and behavioral changes are expected to subside quickly when 
the exposures cease. Level B harassment will be

[[Page 56880]]

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 waterfront with 
vessel traffic from both Navy and non-Navy activities.
    The project is also not expected to have significant adverse 
effects on any marine mammal habitat. The project activities will not 
modify existing marine mammal habitat since the project will occur 
within the same footprint as existing marine infrastructure. Impacts to 
the immediate substrate during installation and removal of piles are 
anticipated, but these would be limited to minor, temporary suspension 
of sediments, which could impact water quality and visibility for a 
short amount of time, but which would not be expected to have any 
effects on individual marine mammals. The nearshore and intertidal 
habitat where the project will occur is an area of consistent vessel 
traffic from Navy and non-Navy vessels, and some local individuals 
would likely be somewhat habituated to the level of activity in the 
area, further reducing the likelihood of more severe impacts. The 
closest pinniped haulout, The Sisters, is used by harbor seals and is 
less than a mile from the project area; however, for the reasons 
described immediately above (including the nature of expected responses 
and the duration of the project), impacts to reproduction or survival 
of individuals is not anticipated, much less effects on the species or 
stock. There are no other biologically important areas for marine 
mammals near the project area.
    In addition, impacts to marine mammal prey species are expected to 
be minor and temporary. Overall, the area impacted by the project is 
very small compared to the available habitat in Narragansett Bay. The 
most likely impact to prey will be temporary behavioral avoidance of 
the immediate area. During pile driving activities, it is expected that 
some fish and marine mammals would temporarily leave the area of 
disturbance, thus 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, the impacts to marine mammal habitat are not 
expected to cause significant or long-term negative consequences.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
    [ssquf] No mortality is anticipated or authorized;
    [ssquf] No Level A harassment is anticipated or authorized for 
Atlantic white-sided dolphins, Short-beaked common dolphins, and hooded 
seals;
    [ssquf] Anticipated incidents of Level B harassment consist of, at 
worst, temporary modifications in behavior;
    [ssquf] The required mitigation measures (i.e., shutdown zones) are 
expected to be effective in reducing the effects of the specified 
activity;
    [ssquf] Minimal impacts to marine mammal habitat/prey are expected;
    [ssquf] The action area is located within an active marine 
waterfront area, and
    [ssquf] There are no known biologically important areas in the 
vicinity of the project, with the exception of one harbor seal haulout 
(The Sisters)--however, as described above, exposure to the work 
conducted in the vicinity of the haulout is not expected to impact the 
reproduction or survival of any individual seals.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under sections 101(a)(5)(A) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers, 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.
    Take of five of the marine mammal stocks authorized will comprise 
at most approximately 2 percent or less of the stock abundance (Table 
18). There are no official stock abundance for harp seals or hooded 
seals; however, we believe for the abundance information that is 
available for Canada (N = 7+million for harp seals and N = 593,500 for 
hooded seals) combined with the fact they are highly migratory species 
and would be rare in the project area, the estimated takes are likely 
very small percentages of the stock abundance. The number of animals 
authorized to be taken from these stocks would be considered small 
relative to the relevant stock's abundances even if each estimated take 
occurred to a new individual, which is an unlikely scenario.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals will be taken relative to the population size 
of the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

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

Adaptive Management

    The regulations governing the take of marine mammals incidental to 
Navy construction activities would contain an adaptive management 
component. The reporting requirements associated with this 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

[[Page 56881]]

research; and (3) any information which reveals that marine mammals may 
have been taken in a manner, extent, or number not authorized by these 
regulations or subsequent LOAs.

Endangered Species Act

    Section 7(a)(2) of the 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 incidental take authorizations, NMFS 
consults internally whenever we propose to authorize take for 
endangered or threatened species.
    No incidental take of ESA-listed species is proposed for 
authorization or expected to result from this activity. Therefore, NMFS 
has determined that formal consultation under section 7 of the ESA is 
not required for this action.

Request for Information

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

Classification

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

List of Subjects in 50 CFR Part 217

    Administrative practice and procedure, Alaska, Endangered and 
threatened species, Exports, Fish, Imports, Indians, Labeling, Marine 
mammals, Oil and gas exploration, Penalties, Reporting and 
recordkeeping requirements, Seafood, Transportation, Wildlife.

    Dated: September 28, 2021.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, 50 CFR part 217 is proposed 
to be amended as follows:

PART 217--REGULATIONS GOVERNING THE TAKE OF MARINE MAMMALS 
INCIDENTAL TO SPECIFIED ACTIVITIES

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. Add subpart R to part 217 to read as follows:
Subpart R--Taking and Importing Marine Mammals Incidental to U.S. Navy 
Construction at Naval Station Newport in Newport, Rhode Island
Sec.
217.70 Specified activity and geographical region.
217.71 Effective dates.
217.72 Permissible methods of taking.
217.73 Prohibitions.
217.74 Mitigation requirements.
217.75 Requirements for monitoring and reporting.
217.76 Letters of Authorization.
217.77 Renewals and modifications of Letters of Authorization.
217.78-217.79 [Reserved]

Subpart R--Taking and Importing Marine Mammals Incidental to U.S. 
Navy Construction at Naval Station Newport in Newport, Rhode Island


Sec.  217.70  Specified activity and geographical region.

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


Sec.  217.71  Effective dates.

    Regulations in this subpart are effective from [EFFECTIVE DATE OF 
THE FINAL RULE] to [DATE 5 YEARS AFTER EFFECTIVE DATE OF THE FINAL 
RULE].


Sec.  217.72  Permissible methods of taking.

    Under an LOA issued pursuant to Sec. Sec.  216.106 of this chapter 
and 217.76, the Holder of the LOA (hereinafter ``Navy'') may 
incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  217.70 (b) by harassment associated with 
construction activities, provided the activity is in compliance with 
all terms, conditions, and requirements of the regulations in this 
subpart and the applicable LOA.


Sec.  217.73  Prohibitions.

    (a) Except for the takings contemplated in Sec.  217.72 and 
authorized by a LOA issued under Sec. Sec.  216.106 of this chapter and 
217.76, it is unlawful for any person to do any of the following in 
connection with the activities described in Sec.  217.70:
    (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 217.76;
    (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 if 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 if NMFS determines 
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.  217.74  Mitigation requirements.

    (a) When conducting the activities identified in Sec.  217.71(a), 
the mitigation measures contained in any LOA issued under Sec. Sec.  
216.106 of this chapter and 217.76 must be implemented. These 
mitigation measures must include but are not limited to:
    (1) A copy of any issued LOA must be in the possession of the Navy, 
its designees, and work crew personnel operating under the authority of 
the issued LOA.

[[Page 56882]]

    (2) The Navy will follow mitigation procedures as described in this 
section. In general, if poor environmental conditions restrict full 
visibility of the shutdown zone, pile driving activities would be 
delayed.
    (3) The Navy will ensure that construction supervisors and crews, 
the monitoring team, and relevant Navy staff are trained prior to the 
start of construction activity subject to this rule, so that 
responsibilities, communication procedures, monitoring protocols, and 
operational procedures are clearly understood. New personnel joining 
during the project will be trained prior to commencing work.
    (4) The Navy will avoid direct physical interaction with marine 
mammals during construction activity. If a marine mammal comes within 
10 m of such activity, operations will cease and vessels will reduce 
speed to the minimum level required to maintain steerage and safe 
working conditions, as necessary, to avoid direct physical interaction.
    (5) For all pile driving activity, the Navy must implement shutdown 
zones with radial distances as identified in a LOA issued under 
Sec. Sec.  216.106 of this chapter and 217.76. If a marine mammal comes 
within or approaches the shutdown zone, such operations must cease.
    (6) The Navy will use soft start techniques when impact pile 
driving. Soft start requires contractors 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 
would occur. A 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. Soft start is not 
required during vibratory pile driving activities.
    (7) The Navy must deploy protected species observers (observers) as 
indicated in its Marine Mammal Monitoring Plan approved by NMFS.
    (8) For all pile driving activities, a minimum of two protected 
species observers (observers) must be stationed at the best vantage 
points practicable to monitor for marine mammals and implement 
shutdown/delay procedures. However, additional monitors will be added 
if warranted by site conditions and/or the level of marine mammal 
activity in the area. Any activity that would result in threshold 
exceedance at or more than 1,000 m would require a minimum of three 
PSOs to effectively monitor the entire region of influence (the full 
extent of potential underwater noise impact (Level A and Level B 
calculated harassment zones)).
    (9) Monitoring must take place from 30 minutes prior to initiation 
of pile driving activity (i.e., pre-start clearance monitoring) through 
30 minutes post-completion of pile driving activity. Pre-activity 
monitoring must be conducted for 30 minutes to ensure that the shutdown 
zone is clear of marine mammals, and pile driving may commence when 
observers have declared the shutdown zone clear of marine mammals. In 
the event of a delay or shutdown of activity resulting from marine 
mammals in the shutdown zone, animals must be allowed to remain in the 
shutdown zone (i.e., must leave of their own volition) and their 
behavior must be monitored and documented. If a marine mammal is 
observed within the shutdown zone, a soft-start cannot proceed until 
the animal has left the zone or has not been observed for 15 minutes. 
Monitoring must occur throughout the time required to drive a pile. If 
work ceases for more than 30 minutes, the pre-activity monitoring of 
the shutdown zones must 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).
    (10) If a marine mammal approaches or enters the shutdown zone, all 
pile driving activities at that location must be halted. If pile 
driving is halted or delayed due to the presence of a marine mammal, 
the activity may not commence or resume until either the animal has 
voluntarily left and been visually confirmed beyond the shutdown zone 
or fifteen minutes have passed without re-detection of the animal.
    (11) Pile driving activity must be halted upon observation of 
either a species entering or within the harassment zone, 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.
    (12) Should environmental conditions deteriorate such that marine 
mammals within the entire shutdown zone would not be visible (e.g., 
fog, heavy rain), the Navy must delay pile driving and pile removal 
until observers are confident marine mammals within the shutdown zone 
could be detected.
    (13) Monitoring must be conducted by trained observers, who must 
have no other assigned tasks during monitoring periods. Trained 
observers must be placed at the best vantage point(s) practicable to 
monitor for marine mammals and implement shutdown or delay procedures 
when applicable through communication with the equipment operator. The 
Navy must adhere to the following additional observer qualifications:
    (i) Independent observers are required;
    (ii) At least one observer must have prior experience working as an 
observer;
    (iii) Other observers may substitute education (degree in 
biological science or related field) or training for experience;
    (iv) Where a team of three or more observers are required, one 
observer must be designated as lead observer or monitoring coordinator. 
The lead observer must have prior experience working as an observer; 
and
    (v) PSOs must be approved by NMFS prior to beginning any activity 
subject to this proposed rule.
    (b) [Reserved]


Sec.  217.75   Requirements for monitoring and reporting.

    (a) The Navy must submit a Marine Mammal Monitoring Plan to NMFS 
for approval in advance of construction.
    (b) The Navy must deploy observers as indicated in its approved 
Marine Mammal Monitoring Plan.
    (c) Observers must be trained in marine mammal identification and 
behaviors. Observers must have no other construction-related tasks 
while conducting monitoring.
    (d) For all pile driving activities, a minimum of two observers 
must be stationed at the active pile driving site or in reasonable 
proximity in order to monitor the shutdown zone.
    (e) The Navy must monitor the Level B harassment zones (areas where 
SPLs are equal to or exceed the 160 dB rms threshold for impact driving 
and the 120 dB rms threshold during vibratory pile driving) to the 
extent practicable and the shutdown zones. For those activities with 
larger Level A (PTS onset) harassment zones, the shutdown zone would be 
limited to 150 m from the point of noise generation to ensure adequate 
monitoring for each bulkhead section and the remaining area would be 
considered part of the disturbance zone. The Navy must monitor the 
disturbance zone, which is the Level B harassment zone and, where 
present, the Level A harassment zone (PTS onset) beyond 150 m from the 
point of noise generation. The Navy must monitor at least a portion of 
the Level B harassment zone on all pile driving days.
    (f) The Navy must conduct hydroacoustic data collection (sound 
source verification and propagation loss) in accordance with a 
hydroacoustic monitoring plan that

[[Page 56883]]

must be approved by NMFS in advance of construction.
    (g) The Navy must submit a draft monitoring report to NMFS within 
90 work days of the completion of required monitoring for each portion 
of the project as well as a comprehensive summary report at the end of 
the project. The report will detail the monitoring protocol and 
summarize the data recorded during monitoring. Final annual reports 
(each portion of the project and comprehensive) 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 
contain the informational elements described at minimum below (and be 
included in the Marine Mammal Monitoring Plan), including:
    (1) Dates and times (begin and end) of all marine mammal 
monitoring;
    (2) Construction activities occurring during each daily observation 
period, including how many and what type of piles were driven or 
removed and by what method (i.e., impact or vibratory) and the total 
duration of driving time for each pile (vibratory driving) and number 
of strikes for each pile (impact driving);
    (3) Environmental conditions during monitoring periods (at 
beginning and end of observer 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 (if less 
than the harassment zone distance);
    (4) Upon observation of a marine mammal, the following information 
should be collected:
    (i) Observer who sighted the animal and observer location and 
activity at time of sighting;
    (ii) Time of sighting;
    (iii) Identification of the animal (e.g., genus/species, lowest 
possible taxonomic level, or unidentified), observer confidence in 
identification, and the composition of the group if there is a mix of 
species;
    (iv) Distances and bearings of each marine mammal observed in 
relation to the pile being driven for each sighting (if pile driving 
was occurring at time of sighting);
    (v) Estimated number of animals (min/max/best);
    (vi) Estimated number of animals by cohort (adults, juveniles, 
neonates, group composition etc.);
    (vii) Animal's closest point of approach and estimated time spent 
within the harassment zone; and
    (viii) Description of any marine mammal behavioral observations 
(e.g., observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses to the activity (e.g., no response 
or changes in behavioral state such as ceasing feeding, changing 
direction, flushing, or breaching);
    (5) Detailed information about any implementation of any mitigation 
(e.g., shutdowns and delays), a description of specific actions that 
ensued, and resulting changes in the behavior of the animal, if any; 
and
    (6) All observer datasheets and/or raw sightings data.
    (h) The Navy must report the hydroacoustic data collected as 
required by a LOA issued under Sec. Sec.  216.106 of this chapter and 
217.76.
    (i) In the event that personnel involved in the construction 
activities discover an injured or dead marine mammal, the Navy must 
report the incident to NMFS Office of Protected Resources (OPR), and to 
the Greater Atlantic Region New England/Mid-Atlantic 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 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 and the 
LOA issued under Sec. Sec.  216.106 of this chapter and 217.76. The 
Navy will not resume their activities until notified by NMFS. The 
report must include the following information:
    (1) Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    (2) Species identification (if known) or description of the 
animal(s) involved;
    (3) Condition of the animal(s) (including carcass condition if the 
animal is dead);
    (4) Observed behaviors of the animal(s), if alive;
    (5) If available, photographs or video footage of the animal(s); 
and
    (6) General circumstances under which the animal was discovered.


Sec.  217.76  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to these 
regulations, the Navy must apply for and obtain an LOA.
    (b) An LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of these regulations.
    (c) If an LOA expires prior to the expiration date of these 
regulations, the Navy may apply for and obtain a renewal of the LOA.
    (d) In the event of projected changes to the activity or to 
mitigation and monitoring measures required by an LOA, the Navy must 
apply for and obtain a modification of the LOA as described in Sec.  
217.77.
    (e) The LOA will 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 will be based on a determination that the 
level of taking will be consistent with the findings made for the total 
taking allowable under these regulations.
    (g) Notice of issuance or denial of an LOA will be published in the 
Federal Register within 30 days of a determination.


Sec.  217.77  Renewals and modifications of Letters of Authorization.

    (a) An LOA issued under Sec. Sec.  216.106 of this chapter and 
217.76 for the activity identified in Sec.  217.70(a) may be renewed or 
modified upon request by the applicant, provided that:
    (1) The proposed specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for these regulations; and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOA under these regulations were 
implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation, monitoring, or 
reporting that do not change the findings made for the regulations or 
result in no more than a minor change in the total estimated number of 
takes (or distribution by species or years), NMFS may publish a notice 
of proposed LOA in the Federal Register, including the associated 
analysis of the change, and solicit public comment before issuing the 
LOA.
    (c) A LOA issued under Sec. Sec.  216.106 of this chapter and 
217.76 for the activity identified in Sec.  217.70 (a) may be

[[Page 56884]]

modified by NMFS under the following circumstances:
    (1) NMFS may modify (including augment) the existing mitigation, 
monitoring, or reporting measures (after consulting with Navy regarding 
the practicability of the modifications) if doing so creates a 
reasonable likelihood of more effectively accomplishing the goals of 
the mitigation and monitoring set forth in the preamble for these 
regulations;
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in a LOA:
    (A) Results from Navy's monitoring from previous years;
    (B) Results from other marine mammal and/or sound research or 
studies; and
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent or number not authorized by these regulations or 
subsequent LOAs; and
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
will 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 217.76, 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.  217.78--217.79  [Reserved]

[FR Doc. 2021-21426 Filed 10-12-21; 8:45 am]
BILLING CODE 3510-22-P