[Federal Register Volume 85, Number 159 (Monday, August 17, 2020)]
[Rules and Regulations]
[Pages 50720-50756]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-15404]



[[Page 50719]]

Vol. 85

Monday,

No. 159

August 17, 2020

Part IV





 Department of Commerce





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 National Oceanic and Atmospheric Administration





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50 CFR Part 217





Takes of Marine Mammals Incidental to Specified Activities; Taking 
Marine Mammals Incidental to Alaska Liquefied Natural Gas (LNG) Project 
in Cook Inlet; Final Rule

  Federal Register / Vol. 85, No. 159 / Monday, August 17, 2020 / Rules 
and Regulations  

[[Page 50720]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 217

[Docket No. 200709-0185]
RIN 0648-BH44


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Alaska Liquefied Natural Gas (LNG) 
Project in Cook Inlet

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

ACTION: Final rule.

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SUMMARY: Upon application from the Alaska Gasline Development 
Corporation (AGDC), NMFS is issuing regulations under the Marine Mammal 
Protection Act (MMPA) for the taking of marine mammals incidental to 
the Alaska Liquefied Natural Gas (LNG) project in Cook Inlet, Alaska, 
over the course of five years (2020-2025). These regulations allow NMFS 
to issue a Letter of Authorization (LOA) for the incidental take of 
marine mammals during the specified construction activities carried out 
during the rule's period of effectiveness, set forth the permissible 
methods of taking, set forth other means of effecting the least 
practicable adverse impact on marine mammal species or stocks and their 
habitat, and set forth requirements pertaining to the monitoring and 
reporting of the incidental take.

DATES: Effective January 1, 2021 through December 31, 2025.

ADDRESSES: To obtain an electronic copy of the AGDC's LOA application 
or other referenced documents, visit the internet at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable. In case of 
problems accessing these documents, please call the contact listed 
below (see FOR FURTHER INFORMATION CONTACT).

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

SUPPLEMENTARY INFORMATION: 

Purpose and Need for Regulatory Action

    This final rule establishes 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 AGDC's construction activities of an 
LNG facility in Cook Inlet, Alaska.
    We received an application from AGDC 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 and pipe laying. 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 Mitigation section), as 
well as monitoring and reporting requirements. Section 101(a)(5)(A) of 
the MMPA and the implementing regulations at 50 CFR part 216, subpart 
I, provide the legal basis for issuing this final rule containing five-
year regulations, and for any subsequent letters of authorization 
(LOAs). As directed by this legal authority, this final rule contains 
mitigation, monitoring, and reporting requirements.

Summary of Major Provisions Within the Final Rule

    Following is a summary of the major provisions of this final rule 
regarding AGDC's construction activities. These measures include:
     Required time/area closure for beluga whale during summer 
months in the western portion of the Cook Inlet;
     Required monitoring of the construction areas to detect 
the presence of marine mammals before beginning construction 
activities;
     Shutdown of construction activities under certain 
circumstances to avoid injury of marine mammals; and
     Soft start for impact pile driving to allow marine mammals 
the opportunity to leave the area prior to beginning impact pile 
driving at full power.

Background

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

[[Page 50721]]

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 issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    Accordingly, NMFS has adopted the Federal Energy Regulatory 
Commission's (FERC's) Final Environmental Impact Statement (FEIS). Our 
independent evaluation of the FEIS found that it includes the requisite 
information analyzing the effects on the human environment of issuing 
the Letter of Authorization (LOA). NMFS is a cooperating agency on the 
FERC's FEIS.
    The FERC's EIS is available at https://www.ferc.gov/industries/gas/enviro/eis/2020/03-06-20-FEIS.asp.

Summary of Request

    On April 18, 2017, NMFS received a request from AGDC for a LOA to 
take marine mammals incidental to constructing LNG facilities in Cook 
Inlet. The application was deemed adequate and complete on March 14, 
2018. AGDC's request is for takes of a small number of five species of 
marine mammals by Level B harassment. On April 11, 2018, NMFS published 
a Notice of Receipt announcing the receipt of AGDC's LOA application 
(83 FR 15556). Further analysis by NMFS concludes that potential 
effects to marine mammals from AGDC's activity could result in Level A 
harassment. Neither AGDC nor NMFS expects serious injury or mortality 
to result from this activity. However, since AGDC's LNG facility 
construction activities are expected to last for five years, an LOA is 
appropriate. On June 28, 2019, NMFS published a proposed rule (84 FR 
30991; June 28, 2019) and proposed regulations to govern takes of 
marine mammals incidental to AGDC's LNG facility construction and 
requested comments on the proposed regulations. After the public 
comment period, NMFS further worked with AGDC to address the public 
comments, which included the addition of monitoring and mitigation 
measures. On February 17, 2020, AGDC submitted a revised LOA 
application that includes these additional monitoring and mitigation 
measures.

Description of Proposed Activity

Overview

    AGDC proposes to construct facilities to transport and offload LNG 
in Cook Inlet, AK, for export. The Project activities include:
     Construction of the proposed Marine Terminal in Cook 
Inlet, including construction of a temporary Marine Terminal Material 
Offloading Facility (Marine Terminal MOF) and a permanent Product 
Loading Facility (PLF);
     Construction of the Mainline (main pipeline) across Cook 
Inlet, including the potential construction of a temporary Mainline 
Material Offloading Facility (Mainline MOF) on the west side of Cook 
Inlet; and
    Components of proposed construction activities in Cook Inlet that 
have the potential to expose marine mammals to received acoustic levels 
that could result in take include:
     Vibratory and impact pile driving associated with Marine 
Terminal MOF and PLF construction; and
     Anchor handling associated with pipe laying across the 
Cook Inlet.
    There is no change in the AGDC's proposed LNG facilities 
construction from what was described in the proposed rule (84 FR 30991; 
June 28, 2019).

Dates and Duration

    AGDC plans to start the Alaska LNG facilities construction on April 
1, 2021, and complete it by the end of October 31, 2025. Construction 
activities would be divided into phases, with all construction 
occurring between April 1 and October 31 each year from 2021 to 2025. 
During the construction season, crews will be working 12 hours per day, 
6 days per week.

Specific Geographic Region

    The Alaska LNG facilities, which include a Marine Terminal and the 
Mainline crossing, will be constructed in Cook Inlet. The Marine 
Terminal would be constructed adjacent to the proposed onshore LNG 
Plant near Nikiski, Alaska.
    In addition, a Mainline Material Offloading Facility (Mainline MOF) 
may be constructed on the west side of Cook Inlet to support 
installation of the Cook Inlet shoreline crossing and onshore 
construction between the Beluga Landing shoreline crossing and the 
Yentna River. The Mainline MOF would be located near the existing 
Beluga Landing.
    A map of the Alaska LNG facilities action area is provided in 
Figure 1 below and is also available in Figures 2 to 4 in the LOA 
application.
BILLING CODE 3510-22-P

[[Page 50722]]

[GRAPHIC] [TIFF OMITTED] TR17AU20.447

BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The construction of the Alaska LNG facilities includes the 
construction of a product loading facility, marine terminal material 
offloading facility, a mainline material offloading facility, and the 
Mainline crossing of Cook Inlet. For all construction activities, each 
season extends from April 1 through October 31, during which 
construction crews would be working 12 hours per day, six days per 
week.

[[Page 50723]]

    The following provides a detailed description of the Alaska LNG 
facilities to be constructed.
Product Loading Facility (PLF)
    The proposed PLF would be a permanent facility used to load LNG 
carriers (LNGCs) for export. It consists of two loading platforms, two 
berths, a Marine Operations Platform, and an access trestle that 
supports the piping that delivers LNG from shore to LNGCs and includes 
all the equipment to dock LNGCs. Analyzed elements of the PLF are shown 
in Figures 3 and 4 of the LOA application, and are described as 
follows.
     PLF Loading Platforms--Two loading platforms, one located 
at either end of the north-south portion of the trestle, would support 
the loading arm package, a gangway, supporting piping, cabling, and 
equipment. The platforms would be supported above the seafloor on 
steel-jacketed structures called quadropods;
     PLF Berths--Two berths would be located in natural water 
depths greater than--53 feet (ft) mean lower low water (MLLW) and would 
be approximately 1,600 feet apart at opposite ends of the north-south 
portion of the trestle. Each berth would have four concrete pre-cast 
breasting dolphins and six concrete pre-cast mooring dolphins. The 
mooring and breasting dolphins would be used to secure vessels 
alongside the berth for cargo loading operations. The mooring and 
breasting dolphins would be supported over the seabed on quadropods. A 
catwalk, supported on two-pile bents, would connect the mooring 
dolphins to the loading platforms;
     Marine Operations Platform--A Marine Operations Platform 
would be located along the east-west portion of the access trestle 
(Figure 4 of the LOA application) and would support the proposed Marine 
Terminal Building, an electrical substation, piping, cabling, and other 
equipment used to monitor the loading operations. The platform would be 
supported above the seafloor on four-pile bents; and
     Access Trestle--This structure is T-shaped with a long 
east-west oriented section and a shorter north-south oriented section 
and carries pipe rack, roadway, and walkway. The pipe rack contains LNG 
loading system pipelines, a fire water pipeline, utility lines, power 
and instrument cables, and lighting. The east-west portion of the 
trestle extends from shore, seaward, for a distance of approximately 
3,650 feet and would be supported on three-pile and four-pile bents at 
120-foot intervals. The north-south oriented portion of the access 
trestle is approximately 1,560 feet long, and is supported on five-pile 
quadropods.
    The PLF would be constructed using both overhead and marine 
construction methods. As planned, the PLF would be constructed over the 
course of four ice-free seasons (Seasons 2-5); however, Season 2 
activities associated with PLF construction include only installation 
of onshore portions of the PLF and are not included in the analysis. 
Activities in Seasons 3 through 5 are described below.
    In Season 3, the marine construction activities would be mobilized 
and the cantilever bridge would be commissioned. A total of 35 bents 
and quadropod structures would be installed for part of the east-west 
and north-south access trestles and berth loading platforms.
    In Season 4, the remainder of the bents for the east-west access 
trestle would be installed. Additionally, bents supporting the Marine 
Operations Platform and north-south trestle would be installed. A total 
of 26 bent and quadropod structures would be installed.
    In Season 5, installation of the mooring quadropods would be 
completed, and the bents supporting the catwalk between the loadout 
platforms and the mooring dolphins would be installed. A total of 18 
bent and quadropod structures would be installed.
    PLF bents and quadropods are expected to be installed with impact 
hammers. The anticipated production rate for installation of the bents 
is one bent per six construction days, and for quadropods it is one 
quadropod per eight work days. Pile driving is expected to occur during 
only two of the six days for bents and two of the eight days for 
quadropods. It is also assumed the impact hammer would only be operated 
approximately 25 percent of time during the two days of pile driving.
Marine Terminal Material Offloading Facility (Marine Terminal MOF)
    The proposed Marine Terminal MOF, to be located near the PLF in 
Nikiski, would consist of three berths and a quay that would be used 
during construction of the Liquefaction Facility to enable direct 
deliveries of equipment modules, bulk materials, construction 
equipment, and other cargo to minimize the transport of large and heavy 
loads over road infrastructure.
    The Marine Terminal MOF quay would be approximately 1,050 feet long 
and 600 feet wide, which would provide sufficient space for cargo 
discharge operations and accommodate 200,000 square feet of staging 
area. It would have a general dock elevation of +32 feet MLLW.
    The quay would have an outer wall consisting of combi-wall 
(combination of sheet piles and pipe piles) tied back to a sheet pile 
anchor wall, and 11 sheet pile coffer cells, backfilled with granular 
materials.
    Berths at the Marine Terminal MOF would include:
     One Lift-on/Lift-off (Lo-Lo) berth with a maintained depth 
alongside of -32 feet MLLW;
     One Roll-on/Roll-off (Ro-Ro) berth with a maintained depth 
alongside of -32 feet MLLW; and
     One grounded barge bed with a ground pad elevation of +10 
feet MLLW.
    The Temporary MOF has been designed as a temporary facility and 
would be removed early in operations when it is no longer needed to 
support construction of the Liquefaction Facility.
    The Temporary MOF would be constructed over the course of two 
construction seasons (Seasons 1 and 2).
    The combi-wall and the first six of eleven coffer cells would be 
installed in Season 1. An equal amount of sheet pile anchor wall would 
be associated with the combi-wall, but this is not considered in the 
analysis as the anchor wall would be driven into fill and would not 
generate substantial underwater sound. Six 24-inch template pipe piles 
would be installed with a vibratory hammer before the sheet pile is 
installed for each coffer cell and then removed when coffer cell 
installation is complete. The remaining five coffer cells and fill 
would be installed in Season 2, along with the quadropods for the 
dolphins for the Ro-Ro berth.
    The Marine Terminal MOF would be constructed using both land-based 
(from shore and subsequently from constructed portions of the Marine 
Terminal MOF) and marine construction methods. The anticipated 
production rate for installation of combi-wall and coffer cells is 25 
linear feet per day per crew, with two crews operating, and vibratory 
hammers operating 40 percent of each 12-hour construction day. The 
anticipated production rate for quadropod installation is the same as 
described in Section 1, above.
    Dredging would be conducted over two ice free seasons. Dredging at 
the Marine Terminal MOF during the first season of marine construction 
may be conducted with either an excavator or clamshell (both mechanical 
dredges). Various bucket sizes may be used. Sediment removed would be 
placed in split hull or scow/hopper barges tended

[[Page 50724]]

by tugs that would transport the material to the location of dredge 
material placement.
    Dredging at the Marine Terminal MOF during the second season may be 
conducted with either a hydraulic (cutter head) dredger or a mechanical 
dredger. For a hydraulic dredger, the dredged material would be pumped 
from the dredge area to the disposal location or pumped into split-hull 
barges for transport to the placement location. If split-hull barges 
are used rather than direct piping of material, a manifold system may 
be set up to load multiple barges simultaneously. For a mechanical 
dredger, two or more sets of equipment would likely be required to 
achieve total dredging production to meet the Project schedule. 
Personnel transfer, support equipment, and supply would be similar to 
the first season. However, due to the low activity level and source 
levels from dredging, we do not consider there would be take of marine 
mammals. Therefore, dredging is not further analyzed in this document.
Mainline Material Offloading Facility (Mainline MOF)
    A Mainline MOF may be required on the west side of Cook Inlet to 
support installation of the Cook Inlet shoreline crossing, and onshore 
construction between the South of Beluga Landing shoreline crossing and 
the Yentna River. The Mainline MOF would be located near, but at a 
reasonable distance, from the existing Beluga Landing. Use of the 
existing landing is not considered to be feasible.
    The Mainline MOF would consist of a quay, space for tugs, and 
berths including:
     Lo-Lo Berth for unloading pipes and construction 
materials;
     Ro-Ro Berth and ramp dedicated to Ro-Ro operations; and
     Fuel berth dedicated to unloading fuel.
    The quay would be 450 feet long (along the shoreline) and 310 feet 
wide (extending into the Cook Inlet). A Ro-Ro ramp (approximately 80 
feet by 120 feet) would be constructed adjacent to the quay. Both the 
quay and the Ro-Ro ramp would consist of anchored sheet pile walls 
backed by granular fill. The sources for the granular material would be 
onshore. Surfacing on the quay would be crushed rock. Some fill 
material for the quay and Ro-Ro ramp are expected to be generated by 
excavation of the access road. Any additional needed fill materials and 
crushed rock for surfacing would be barged in.
    The quay and the Ro-Ro ramp are located within the 0-foot contour, 
so berths would be practically dry at low tide. No dredging is planned; 
vessels would access the berths and ground themselves during high tide 
cycles. The proposed top level of the Mainline MOF is +36 feet MLLW, 
which is about 11 feet above Mean Higher High Water (MHHW).
    Approximately 1,270 feet of sheet pile would be installed for 
construction of the quay and Ro-Ro ramp, and a corresponding length of 
sheet pile would be installed as anchor wall; however, only 670 feet of 
sheet pile would be installed in the waters of Cook Inlet. The 
remainder would be installed as anchor wall in fill material, or in the 
intertidal area when the tide is out, and would not result in 
underwater sound.
    The Mainline MOF would be constructed in a single construction 
season (Season 1). A break-down of activities per season is provided 
below. Crews are expected to work 12 hours per day, six days per week. 
The sheet pile would be installed using marine equipment, with the 
first 50 percent of embedment conducted using a vibratory hammer and 
the remaining 50 percent conducted using an impact hammer. Hammers 
would be expected to be operated either 25 percent of a 12-hour 
construction day (impact hammer) or 40 percent of a 12-hour 
construction day (vibratory hammer).
Mainline Crossing of Cook Inlet
    The proposed Mainline, a 42-inch-diameter, natural gas pipeline, 
would cross the Cook Inlet shoreline on the west side of the inlet 
(north landfall) south of Beluga Landing at pipeline milepost (MP) 
766.3, traverse Cook Inlet in a generally southward direction for 
approximately 26.7 miles, and cross the east Cook Inlet shoreline near 
Suneva Lake at MP 793.1 (south landfall). The pipe would be trenched 
into the seafloor and buried from the shoreline out to a water depth of 
approximately 35-45 feet MLLW on both sides of the inlet, approximately 
8,800 feet from the north landfall and 6,600 feet from the south 
landfall. Burial depth (depth of top of pipe below the seafloor) in 
these areas would be 3-6 feet. Seaward of these sections, the concrete 
coated pipeline would be placed on the seafloor. Additional footprint 
would be impacted by the use of anchors to hold the pipelay vessel in 
place while installing the pipeline on the seafloor.
    Geophysical surveys would be conducted just prior to pipeline 
construction. A detailed bathymetric profile (longitudinal and cross) 
would be conducted. Types of geophysical equipment expected to be used 
for the surveys could include:
     Single-beam echosounder planned for use during this 
program operate at frequencies greater than 200 kilohertz (kHz);
     Multi-beam echo sounders planned for this program operate 
at frequencies greater than 200 kHz;
     Side-scan sonar system planned for use during this program 
operate at a frequency of 400 and 900 kHz; and
     Magnetometer. These instruments do not emit sound.
    Operation of geophysical equipment such as echosounders and side-
scan sonars at frequencies greater than 200 kHz are not considered to 
result in takes of marine mammals due to the extremely high frequencies 
emitted that are above the range of marine mammals' hearing thresholds. 
Magnetometers do not emit underwater sound. Therefore, geophysical 
surveys are not evaluated further in this document.
    The pipeline would be trenched and buried in the nearshore portions 
of the route across the Cook Inlet.
    The nearshore portion of the trench is expected to be constructed 
using amphibious or barge-based excavators. This portion of the trench 
would extend from the shoreline out to a transition water depth where a 
dredge vessel can be employed. On the west side of the inlet (Beluga 
Landing) this is expected to be from the shore out 655 feet, and on the 
east side (Suneva Lake) from the shoreline out 645 feet. The trench 
basis is to excavate a mustow slope trench that would not retain 
sediments (i.e., a self-cleaning trench). A backhoe dredge may also be 
required to work in this portion of the crossing.
    From the transition water depth to water depths of the -35 feet or 
-45 feet MLLW, a trailing suction hopper dredger would be used to 
excavate a trench for the pipeline. Alternative burial techniques, such 
as plowing, backhoe dredging, or clamshell dredging, would be 
considered if conditions become problematic for the dredger. After 
installation of the nearshore pipelines, a jet sled or mechanical 
burial sled could be used to achieve post dredge burial depths.
    Pipeline joints would be welded together onshore in 1,000-foot-long 
strings and laid on the ground surface in an orientation that 
approximates the offshore alignment. A pipe pull barge would be 
anchored offshore near the seaward end of the trench, and would then be 
used to pull the pipe strings from their onshore position, out into the 
trench.
    Following pipeline installation, the trench is expected to backfill 
naturally through the movement of seafloor sediments. If manual 
backfilling is

[[Page 50725]]

required, the backfill would be placed by reversing the flow of the 
trailing suction hopper dredger used offshore (see below) or 
mechanically with the use of excavators.
    Seaward of the trenched sections, the pipeline would be laid on the 
seafloor across Cook Inlet using conventional pipelay vessel methods. 
The pipelay vessel would likely employ 12 anchors to keep it positioned 
during pipe laying and provide resistance as it is winched ahead 80 
feet each time an additional 80-foot section of pipe is added/welded on 
the pipe string. Dynamic positioning may be used in addition to the 
conventional mooring system. Mid-line buoys may be used on the anchor 
chains when crossing other subsea infrastructure (i.e., pipelines and 
cables). A pipe laying rate of 2,000 to 2,500 feet per 24-hour period 
is expected. It is anticipated that three anchor handling attendant 
tugs would be used to repeatedly reposition the anchors, thereby 
maintaining proper position and permitting forward movement. The 
primary underwater sound sources of concern would be from the anchor 
handling tugs (AHTs) during the anchor handling for the pipelay vessel.
    The pipeline crossing of Cook Inlet would be installed in two 
consecutive construction seasons (Seasons 3 and 4). Work from the 
pipelay vessel and pull barge would be conducted 24 hours per day, 
seven days per week, until the work planned for that season is 
completed. Anchor handling durations were estimated differently for the 
two construction seasons. Anchor handling is expected to be conducted 
25 percent of the time that the pull barge is on site in Season 3. The 
estimate for anchor handling duration in Season 4 was based on the 
proposed route length, the total numbers of individual anchors moves, 
and the estimated time required to retrieve and reset each anchor 
(approximately 30 minutes per anchor to retrieve and reset). A break-
down of activities per season is provided below.
    Activities in Season 3 in include:
     Conduct onshore enabling works including establishing 
winch/laydown and welding area, and excavation of a trench through 
onshore sections of the shore approach (open cut the shoreline).
     Excavate trench in very nearshore waters using land and 
amphibious excavation equipment.
     Conduct pre-lay excavation of the pipe trench out to 
depths of -35 to -45 feet MLLW using various subsea excavation methods.
     Install the pipe in the nearshore trenches using a pull 
barge.
    Anchor handling would occur for approximately six (5.75 days) 24-
hour periods in Season 3.
    Activities in Season 4 include:
     Lay unburied offshore section of Mainline across Cook 
Inlet using conventional pipelay vessel. The Applicant estimates that 
anchor handling would occur over 13 24-hour periods in Season 4.
     Tie-in the offshore section to the buried nearshore 
sections on both sides of the Cook Inlet.
     Flood, hydrotest, and dry the Mainline pipeline with Cook 
Inlet.
    A summary of pile driving activities for the entire Alaska LNG 
facilities construction, breaking down by seasons and project elements, 
is provided in Table 1.

                                    Table 1--In-Water Pile Driving Associated With Alaska LNG Facilities Construction
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                          Number strikes/
            Element                Driving method    Pile type & size    Pile number or     hr (impact      Hours pile      Number days    Total piling
                                                                             length            only)        driving/day                        hours
--------------------------------------------------------------------------------------------------------------------------------------------------------
Season 1:
    Marine Terminal MOF combi    Vibratory........  60-in steel pipe.  35...............              NA              11              11             120
     wall.
    Marine Terminal MOF combi    Vibratory........  Sheet pile.......  1075 ft..........              NA              11              11             120
     wall.
    Marine Terminal MOF cell...  Vibratory........  18-in steel pipe.  36...............              NA              11              28             288
    Marine Terminal MOF cell...  Vibratory........  Sheet pile.......  2454 ft..........              NA             9.5              28             264
Season 2:
    Marine Terminal MOF cell...  Vibratory........  18-in steel pipe.  30...............              NA              10              27             264
    Marine Terminal MOF cell...  Vibratory........  Sheet pile.......  2447 ft..........              NA              10              27             264
    Marine Terminal MOF Ro-Ro    Impact...........  24-in steel pipe.  7................            1560               7               7              48
     dolphin quads.
    Marine Terminal MOF Ro-Ro    Impact...........  48-in steel pipe.  28...............            1560               7               7              48
     dolphin quads.
    Mainline MOF...............  Vibratory........  Sheet pile.......  670 ft...........              NA            10.5               7              72
    Mainline MOF...............  Impact...........  Sheet pile.......  670 ft...........            1560               7               7              48
Season 3:
    Berth 1....................  Impact...........  48-in steel pipe.  20...............            1560               6               8              48
    Berth 2....................  Impact...........  48-in steel pipe.  20...............            1560               6               8              48
    N-S access trestle.........  Impact...........  48-in steel pipe.  40...............            1560               6              16              96
    E-W access trestle.........  Impact...........  60-in steel pipe.  33...............            1560             6.6              22             144
    E-W access trestle.........  Impact...........  60-in steel pipe.  40...............            1560               6              20             120
Season 4:
    Breasting dolphin berths 1   Impact...........  Steel pipe 48-in.  8................            1560               6               4              24
     & 2.

[[Page 50726]]

 
    Breasting dolphin berths 1   Impact...........  60-in steel pipe.  32...............            1560               6              12              72
     & 2.
    Mooring dolphin............  Impact...........  48-in steel pipe.  2................            1560              12               2              24
    Mooring dolphin............  Impact...........  60-in steel pipe.  8................            1560              12               2              24
    N-S access trestle.........  Impact...........  48-in steel pipe.  30...............            1560               6              12              72
    E-W access trestle.........  Impact...........  60-in steel pipe.  28...............            1560               7              14              96
    Operation platform.........  Impact...........  60-in steel pipe.  12...............            1560               8               6              48
Season 5:
    Mooring dolphin............  Impact...........  48-in steel pipe.  10...............            1560               8               6              48
    Mooring dolphin............  Impact...........  60-in steel pipe.  40...............            1560               7              14              96
    Catwalk....................  Impact...........  60-in steel pipe.  8................            1560               6              16              96
--------------------------------------------------------------------------------------------------------------------------------------------------------

    A summary of anchor handling activities associated to mooring, 
trenching, and pipe laying are provided in Table 2.

     Table 2--Duration of Anchor Handling Associated With Alaska LNG
                           Facilities Project
------------------------------------------------------------------------
        Season              Activity         Hours/day         Days
------------------------------------------------------------------------
3.....................  Mooring.........            6.00               9
3.....................  Pipe trenching..            6.00              14
4.....................  Pipeline days at            6.00              53
                         a rate of 2,500
                         feet per day.
------------------------------------------------------------------------

Comments and Responses

    NMFS published a Proposed Rule in the Federal Register on June 28, 
2019 (84 FR 30991). During the 30-day public comment period on the 
Proposed Rule, NMFS received comments from the Marine Mammal Commission 
(Commission), Center for Biological Diversity (CBD), Cook Inletkeeper, 
Friends of Animals (FoA), Environmental Investigation Agency (EIA), 
Defenders of Wildlife (DoF), and an anonymous person. All relevant 
comments and responses are provided below.
    Comment 1: The Commission, CBD, Cook Inletkeeper, DoW, and EIA 
state that they are concerned about the potential cumulative impacts of 
human activities on the endangered Cook Inlet beluga whale population. 
The Commission in particular recommends that NMFS defer issuance of a 
final rule to AGDC or any other applicant proposing to conduct sound-
producing activities in Cook Inlet until it has a reasonable basis for 
determining that authorizing any additional incidental harassment takes 
of Cook Inlet beluga whales would not contribute to or exacerbate the 
stock's decline. CBD, Cook Inletkeeper, FoA, and the anonymous person 
request that NMFS deny AGDC's request for an MMPA incidental take 
authorization.
    Response: In accordance with our implementing regulations at 50 CFR 
216.104(c), we use the best available scientific evidence to determine 
whether the taking by the specified activity within the specified 
geographic region will have a negligible impact on the species or stock 
and will not have an unmitigable adverse impact on the availability of 
such species or stock for subsistence uses. Based on the scientific 
evidence available, which includes the inclusion of updated density 
estimates for Cook Inlet beluga whales as well as consideration of the 
revised abundance estimates (NMFS 2020), NMFS determined that the 
impacts of the AGDC LNG facility construction activities, which are 
primarily acoustic in nature, would meet these standards.
    In addition, NMFS worked with AGDC and developed a suite of 
rigorous monitoring and mitigation measures to reduce impacts to Cook 
Inlet beluga whales and other marine mammals to the lowest level 
practicable. Some of the major measures that were put in place after 
the Proposed Rule was published include: (1) Time/area restriction to 
minimize underwater noise input in the Susitna River delta during 
summer months (to reduce impacts to belugas during important foraging 
behaviors) by prohibiting in-water pile driving in west Cook Inlet; (2) 
requiring AGDC to implement shutdown measures for beluga whales to 
prevent Level B harassment, shutdown measures for humpback whales and 
killer whales to prevent Level A harassment, and a 1,000-m exclusion 
zone for harbor porpoises and harbor seals to reduce Level A 
harassment; and (3) requiring AGDC to test the effectiveness of air 
bubble curtains around in-water pile driving. If the results of passive 
acoustic monitoring show that the air bubble curtain can reduce the 
source level by 2-dB or greater for a specific type of pile, AGDC will 
be required to deploy the air bubble curtain system for the driving of 
such piles. These additional mitigation measures are expected to 
further reduce both the number and severity of marine mammal takes, 
particular the Cook Inlet beluga whale, in the AGDC LNG facility 
construction area. NMFS included these additional mitigation measures 
after working with AGDC and determined that they are

[[Page 50727]]

practicable to further reduce potential impacts to Cook Inlet beluga 
whales.
    Our analysis indicates that issuance of these regulations will not 
contribute to or worsen the observed decline of the Cook Inlet beluga 
whale population. Additionally, the ESA Biological Opinion determined 
that the issuance of regulations is not likely to jeopardize the 
continued existence of the Cook Inlet beluga whales or destroy or 
adversely modify Cook Inlet beluga whale critical habitat. The 
Biological Opinion also outlined Terms and Conditions and Reasonable 
and Prudent Measures to reduce impacts, which have been incorporated 
into the rule. Therefore, based on the analysis of potential effects, 
the parameters of the activity, and the rigorous mitigation and 
monitoring program, NMFS determined that the activity would have a 
negligible impact on the population.
    Moreover, the LNG facility construction activity would take only 
small numbers of marine mammals relative to their population sizes. As 
described in the proposed rule notice, NMFS used a method that 
incorporates density of marine mammals overlaid with the anticipated 
ensonified area to calculate an estimated number of takes for belugas, 
which was estimated to be less than 10% of the stock abundance. The 
refined analysis using a 1 km by 1 km grid of Cook Inlet beluga whale 
density later showed that the estimated take would be even smaller (see 
detailed discussion in Estimated Take section below), at less than 5% 
of the population for any given year, which NMFS considers small. Based 
on all of this information, NMFS determined that the number of beluga 
whales likely to be taken is small.
    Comment 2: The Commission recommends that NMFS ensure that AGDC's 
draft environmental impact statement (EIS) addresses the cumulative 
impacts of AGDC's proposed activities and all other sound-producing 
activities on beluga whales, as well as other marine mammals. CBD, Cook 
Inletkeeper, and EIA also comment that NMFS did not provide adequate 
analysis for how it arrived at its take estimates and negligible impact 
finding, and that NMFS did not look into the ongoing and cumulative 
impacts of the proposed activities combined with other foreseeable 
activities in Cook Inlet.
    Response: Both the statute and the agency's implementing 
regulations call for analysis of the effects of the applicant's 
activities on the affected species and stocks, not analysis of other 
unrelated activities and their impacts on the species and stocks. That 
does not mean, however, that effects on the species and stocks caused 
by other non-AGDC activities are ignored. The preamble for NMFS' 
implementing regulations under section 101(a)(5) (54 FR 40338; 
September 29, 1989) explains in response to comments that the impacts 
from other past and ongoing anthropogenic activities are to be 
incorporated into the negligible impact analysis via their impacts on 
the environmental baseline. Consistent with that direction, NMFS has 
factored into its negligible impact analyses the impacts of other past 
and ongoing anthropogenic activities via their impacts on the baseline 
(e.g., as reflected in the density/distribution and status of the 
species, population size and growth rate, and other relevant 
stressors). See the Analysis and Negligible Impact Determination 
section of this rule.
    Regarding the analysis supporting the take estimates and the 
negligible impact finding, for the assessments of potential impacts to 
Cook Inlet beluga whales and other marine mammals in the vicinity of 
AGDC's LNG facilities construction area, NMFS evaluated the noise 
sources as well as other stressors produced by the construction 
activities. We analyzed the noise source types, source levels, and the 
duration of noise-producing activities, as well as the expanses of 
ensonified areas in different seasons, to estimate the number of marine 
mammals that would be exposed to noise levels that could result in 
takes--both in the forms of Level A harassment and Level B harassment. 
In addition, NMFS analyzed the likely impacts of those takes on 
individual marine mammals and the impact on their habitat, including 
marine mammal prey species and the Cook Inlet beluga whale critical 
habitat, to support the determination that the authorized takes will 
result in a negligible impact to the affected species and stocks. These 
analyses were detailed in the Potential Effects of Specified Activities 
on Marine Mammals and Their Habitat and Estimated Takes by Incidental 
Harassment sections in the proposed rule (84 FR 39931; June 18, 2019).
    Our 1989 final rule for the MMPA implementing regulations also 
addressed public comments regarding cumulative effects from future, 
unrelated activities. There we stated that such effects are not 
considered in making findings under section 101(a)(5) concerning 
negligible impact. We indicated that NMFS would consider cumulative 
effects that are reasonably foreseeable when preparing a NEPA analysis 
and also that reasonably foreseeable cumulative effects would be 
considered under section 7 of the ESA for ESA-listed species. 
Accordingly, detailed analysis of the cumulative impacts of the 
proposed activities combined with other foreseeable activities 
(including sound-producing activities) in Cook Inlet is provided in 
FERC's FEIS and, further, the reasonably foreseeable cumulative effects 
on listed species are considered in NMFS biological opinion.
    Comment 3: The Commission also recommends that NMFS establish 
annual limits on the total number and types of takes that are 
authorized for all sound-producing activities in Cook Inlet before 
issuing the final rule. FoA states that the proposed project would have 
more than a negligible impact when analyzed in combination with other 
authorizations.
    Response: As mentioned above, under the MMPA NMFS is required to 
make our required determinations for the specified activity and, 
therefore, establishing limits on the total number of takes authorized 
across multiple actions is inappropriate. Further, setting limits on 
the number and types of takes across all projects is also unnecessary 
in the context of the consideration of AGDC's activity. There are few 
incidental takes of Cook Inlet beluga whales currently authorized under 
the MMPA in Cook Inlet, and the projects for which takes are authorized 
are separated spatially and temporally. NMFS considered the effects of 
potential overlap in projects and the effects of sources other than 
those authorized for incidental take on Cook Inlet beluga whales in the 
Cumulative Effects section of the FERC's Final EIS. The analysis 
concludes that the issuance of an authorization to AGDC for the 
proposed LNG facility construction in Cook Inlet would not have 
significant impacts to Cook Inlet beluga whale and other marine mammals 
in the study area, provided that prescribed monitoring and mitigation 
measures are implemented.
    Comment 4: The Commission recommends that NMFS require AGDC to 
submit a stakeholder engagement plan that includes stakeholders 
contacted (or to be contacted), a summary of input received, a schedule 
for ongoing community engagement, and measures that would be 
implemented to mitigate any potential conflicts with subsistence 
hunting.
    Response: NMFS worked with AGDC to ensure that AGDC engages with 
stakeholders throughout the project area, including Cook Inlet, 
including submission of a Stakeholder Engagement Plan (Plan). AGDC 
provided the Plan to NMFS in April 2020, which includes a list of

[[Page 50728]]

stakeholders to be further contacted, and implementation of the Plan 
through communication. The Plan provides a detailed analysis of 
subsistence use of marine mammals in the Cook Inlet area, which 
indicates that Cook Inlet does not have as strong of a subsistence 
hunting community. Nevertheless, AGDC stated in the Plan that it will 
actively involve subsistence communities in the process, hearing 
concerns, and responding to issues. No concerns were raised by 
subsistence users through this process. Through the Stakeholder 
Engagement Plan, AGDC would implement measures to keep subsistence 
users in the Cook Inlet region informed of its project activities.
    Comment 5: The Commission states that the estimated mean density of 
beluga whales of 0.000158 animals/km\2\ near the temporary MOF appears 
to be an underestimate when compared to densities used by other recent 
applicants to estimate takes associated with activities in similar 
areas of Cook Inlet. The Commission further states that density 
estimates for beluga whales in Cook Inlet are typically derived from a 
habitat model developed by Goetz et al. (2012), which generated density 
for each 1-square-km cell of Cook Inlet. The Commission recommends that 
NMFS ensure consistency in density estimates used by applicants for 
beluga whales in Cook Inlet and update relevant habitat density models 
as new information becomes available.
    Response: Density estimates for beluga in Cook Inlet in the 
Proposed Rule did use a habitat based model developed by Goetz et al. 
(2012). The analysis separated the data into upper, middle, and lower 
Cook Inlet; and the Goetz model is provided in GIS so that a specific 
density can be selected for a specific location. AGDC used the highest 
density estimate for each project location, which in all cases was the 
Goetz model for the specific area.
    After the Proposed Rule was published, AGDC conducted additional 
analyses using Goetz et al. (2012) modeled aerial survey data collected 
by NMFS between 1993 and 2008 and developed beluga whale summer 
densities for each 1-square-kilometer cell of Cook Inlet. To develop a 
density estimate associated with Project components, the GIS files of 
the predicted ensonified area for both Level A and Level B harassment 
associated with each location and pile type, size, and hammer was 
overlain with the GIS file of the 1-square-kilometer beluga density 
cells. The cells falling within each ensonified area were provided in 
an output spreadsheet, and an average cell density for each Project 
component was calculated. This level of detailed analysis shows that 
average beluga whale density near the temporary MOF is 0.00005 animal/
km\2\.
    Regarding the Commission's recommendation that NMFS ensure 
consistency across authorization, while we agree that the best 
available science should consistently be used to support density 
estimates for all projects, we disagree that this means the identical 
density estimate must necessarily be used for all projects. Density 
estimates themselves may appropriately vary to best inform activities 
conducted at varied temporal and spatial scales.
    Comment 6: For harbor seal take estimates, the Commission 
recommends that NMFS use the haul-out correction factor of 2.33 from 
Boveng et al. (2012) to revise the yearly abundance estimates and 
resulting density estimates and recalculate the number of takes 
accordingly. The Commission also recommends that NMFS use the gray 
whale and harbor porpoise densities specified in Table 9 of the Hilcorp 
Final Rule (84 FR 37481; July 31, 2019) and recalculate the numbers of 
takes accordingly. The Commission further recommends that NMFS (1) 
consult with researchers at the Alaska Fisheries Science Center that 
specialize in both cetacean and pinniped density derivation to ensure 
it is compiling, enumerating, and analyzing the aerial sightings data 
and estimating the various marine mammal densities correctly and (2) 
use marine mammal densities consistently for all future incidental take 
authorizations in Cook Inlet.
    Response: NMFS consulted with researchers at the Alaska Fisheries 
Science Center and revised the yearly abundance estimates and resulting 
density estimates and recalculated the number of takes of harbor seals 
and harbor porpoises as suggested by the Commission (pers. comm.; J. 
London; April 16, 2020). The revised abundance and density estimates 
are used in take calculation described in the Estimated Take section.
    The gray whale was not originally included in the AGDC LOA 
application, as it was added by NMFS in the Proposed Rule. Further 
analysis (see Description of Marine Mammals in the Area of Specified 
Activities section) led us to conclude that takes of gray whale are 
highly unlikely in upper Cook Inlet where AGDC's construction activity 
is located. Therefore, this species is not included in the analysis for 
the final rule.
    NMFS addressed the comment about density estimation consistency in 
our response to the previous comment.
    Comment 7: The Commission states that animal modeling that 
considers various operational and animal scenarios is the best way to 
determine the appropriate accumulation time to assess acoustic impacts. 
The Commission recommends that NMFS continue to make a priority to 
address the modeling issue to resolve in the near future and consider 
incorporating animal modeling into its user spreadsheet for acoustic 
impact assessment.
    Response: NMFS has formed a working group to explore and develop 
such a model-based approach as discussed in the comment.
    Comment 8: The Commission, CBD, and Cook Inletkeeper point out that 
AGDC's method for estimating days of pile driving activities, which 
sums fractions of days in which activities occur to generate the total 
number of days for each proposed activity, is inconsistent with NMFS' 
policy for enumerating takes for construction activities in general and 
underestimated the numbers of days of pile driving activity and Level A 
and Level B takes. The Commission recommends that NMFS revise the 
numbers of Level A and Level B harassment takes for all marine mammal 
species to reflect the actual number of days that impact and vibratory 
pile driving will occur, regardless of the duration of those activities 
on a given day.
    Response: NMFS worked with AGDC to better characterize the activity 
and quantify the days of pile driving. Given that the precise number of 
piles to be installed or removed is generally unknown, the actual 
number of pile driving days is used in the revised take calculation to 
calculate potential takes, as recommended.
    Comment 9: The Commission recommends that NMFS refrain from 
authorizing Level A harassment takes for species in which the proposed 
activities are not likely to result in Level A harassment takes during 
vibratory pile and sheet pile driving, which includes harbor porpoises, 
Dall's porpoises, Steller sea lions, and California sea lions.
    Response: NMFS worked with AGDC and evaluated the potential impact 
to marine mammal species in the project area and reassessed the 
likelihood of the species' presence. Based on the reassessment, NMFS 
determined that it is highly unlikely that AGDC's proposed construction 
activities would result in Level A harassment of Dall's porpoise, 
Steller sea lion, or California sea lion in the project area, due to 
extra-limital distribution of these species. However, presence of 
harbor porpoise has been

[[Page 50729]]

confirmed near the AGDC's project location. In addition, the relatively 
large Level A harassment zone for high-frequency cetaceans and the 
difficulty of detection harbor porpoise in the field make it 
challenging to implement shutdown measures in a timely fashion. 
Therefore, we consider the possibility that harbor porpoise could be 
taken by Level A harassment if AGDC PSOs fail to detect an animal 
before it enters an exclusion zone and remains for the amount of time 
necessary to incur PTS. The possibility of harbor porpoise Level A 
harassment is also confirmed by our calculations (see Estimated Take 
section). Accordingly, a small number of Level A harassment takes of 
harbor porpoise have been analyzed and authorized.
    Comment 10: The Commission recommends that NMFS (1) require AGDC to 
provide a detailed hydroacoustic monitoring plan, (2) provide the plan 
to the Commission for review, and (3) include in the final rule, the 
requirement to conduct hydroacoustic monitoring during impact and 
vibratory pile driving of each pile type to verify and adjust the 
extents of the Level A and B harassment zones, as necessary.
    Response: NMFS required AGDC to provide a detailed hydroacoustic 
monitoring plan for its pile driving activities associated with the LNG 
facility construction in Cook Inlet and received the plan in February 
2020. NMFS has provided the plan to the Commission for review and 
addressed all comments and questions from the Commission. NMFS also 
required AGDC to conduct hydroacoustic monitoring at the beginning of 
in-water pile driving of each pile type to verify and adjust the 
extents of the Level A and Level B harassment zones, as necessary.
    Comment 11: The Commission states that the proposed number of Level 
A and B harassment takes also are not allocated appropriately based on 
the extents of the Level A and B harassment zones. As an example, the 
Commission points out that in Year 5, the Level A harassment zone for 
high-frequency cetaceans during impact installation of 48- and 60-in 
pile is 4,524 m, which is 97 percent of the Level B harassment zone of 
4,642 m. However, NMFS proposed to authorize 10 Level A harassment 
takes and 20 Level B harassment takes of harbor porpoises for that 
year. The Commission recommends that NMFS reallocate the proposed Level 
A and B harassment take for low-frequency and high-frequency for Years 
2, 3, 4, and 5 to ensure that the authorized limits reflect the 
relative extents of each harassment zone.
    Response: NMFS worked with AGDC and recalculated the takes based on 
animal density, ensonified area, and pile driving days. The estimated 
takes conservatively reflect the relative extents of each harassment 
zone. However, it is important to note that while NMFS agrees that 
comparison of the areas of the Level B and Level A harassment zones is 
a useful qualitative consideration, we do not agree with the 
Commission's premise that takes must necessarily be allocated 
proportionally to the areas of the Level B and Level A harassment 
zones, as these two ``zones'' do not represent the same thing. The 
Level B harassment zone is based on a threshold utilizing a metric of 
instantaneous exposure and the general underlying assumption is that if 
an animal enters this zone, even momentarily, it will be exposed above 
the received level threshold for Level B harassment and thereby taken. 
Alternately, the thresholds for incurring PTS are not solely based on 
an instantaneous exposure to some level of sound, they are based on an 
accrual of energy that results from a combination of the animal's 
proximity to the source and the time spent there. The isopleth produced 
by NMFS' User Spreadsheet (which delineates the Level A harassment 
zone) includes an assumption about the amount of time that an animal 
would need to remain within the distance identified and, therefore, 
does not support the assumption that any animal that enters the zone, 
even briefly, is taken by Level A harassment. Animals that only come 
within the outer edges of the Level A zone would need to remain there 
near the full duration of time indicated for the full day of pile 
driving operation to incur PTS (typically 30 minutes to multiple 
hours), while animals coming further within the zone would need to 
remain for progressively shorter amounts of time as they get closer to 
the source to risk incurring PTS.
    Comment 12: The Commission states that AGDC would not be able to 
monitor the entire Level B harassment zones due to the extent of these 
zones and recommends that NMFS specify how AGDC should enumerate the 
numbers of marine mammals taken particularly when observers are only 
monitoring a portion of the Level A and B harassment zones.
    Response: NMFS has worked with AGDC on the effectiveness of marine 
mammal monitoring for extended distances and concluded that if the 
protected species observers (PSOs) are placed in locations with 
appropriate height and equipment, they are able to detect beluga whales 
out to 1.5 km from the site on clear days. However, during less ideal 
visibility conditions when only a portion of the Level B harassment 
zone is visible, AGDC are required to enumerate the numbers of marine 
mammal taken based on take number within the area that is within the 
visual observation corrected by the proportion of area beyond visual 
observation.
    Comment 13: The Commission recommends that NMFS require AGDC to 
keep a tally of the numbers of marine mammals taken, alert NMFS when 
the authorized limit is close to being met, and follow any guidance 
provided.
    Response: AGDC is required to keep a tally of the number of marine 
mammals taken and alert NMFS when the authorized limit is close to 
being met based on prescribed monitoring measured in the final rule. In 
addition, AGDC is required to keep a tally of all marine mammal 
sightings during the pile driving activities.
    Comment 14: The CBD and Cook Inletkeeper state that NMFS did not 
adequately consider the impacts to Cook Inlet beluga whale critical 
habitat.
    Response: The Cook Inlet beluga whale critical habitat is 
adequately addressed in the Negligible Impact Analysis and 
Determination section. We noted that AGDC's LNG facilities construction 
activities could potentially impact Cook Inlet beluga whale critical 
habitat. Satellite-tagging studies and aerial survey indicate that 
seasonal shifts exist in Cook Inlet beluga whale distribution, with the 
whales spending a great percentage of time in coastal areas during the 
summer and early fall (June through October or November), and 
dispersing to larger ranges that extend to the middle of the inlet in 
winter and spring (November or December through May). However, fine 
scale modeling based on NMFS long-term aerial survey data indicate that 
the AGDC's proposed LNG facilities construction does not overlap with 
beluga whale high density areas during the summer and fall (Goetz et 
al., 2012).
    Further, NMFS also addressed potential effects on beluga whale prey 
species. Studies have shown that fish reacted to sounds when the sound 
level increased to about 20 dB above the detection level of about 120 
dB (Ona, 1988); however, the physical injury and mortality to fish only 
occurred in the immediate vicinity of impact pile driving (Caltrans, 
2015). Therefore, it is highly unlikely that in-water impact pile 
driving would cause noticeable level fish injury or mortality. During 
the Alaska LNG facilities construction, only a small fraction of the 
available habitat would be ensonified at any given time. Disturbance to 
fish species would be

[[Page 50730]]

short-term, and fish would return to their pre-disturbance behavior 
once the pile driving activity ceases.
    Furthermore, potential impacts to Cook Inlet beluga whale critical 
habitat were also addressed in the FERC's FEIS, of which NMFS is a 
cooperating agency. In addition, the ESA Biological Opinion determined 
that the issuance of regulations is not likely to jeopardize the 
continued existence of the Cook Inlet beluga whales or destroy or 
adversely modify Cook Inlet beluga whale critical habitat. NMFS 
adequately considered impacts in critical habitat in the analyses 
supporting its determination.
    Comment 15: Citing a study by Mooney et al. (2018), the CBD and 
Cook Inletkeeper claim that NMFS thresholds of 120 dB re 1[micro]Pa 
(rms) for continuous and 160 dB re 1[micro]Pa (rms) for impulsive or 
intermittent sources to determine Level B harassment are insufficiently 
conservative to protect Cook Inlet beluga whale because beluga whales 
are highly sensitive to noise.
    Response: The study CBD and Cook Inletkeeper cited addresses the 
variation of hearing sensitivity in a wild beluga whale population 
Bristol Bay, AK. The study used auditory evoked potential (AEP) to 
obtain audiograms of 26 wild beluga whales during capture-release 
events. The results showed that most beluga whales from the study 
showed sensitive hearing with low thresholds (<80 dB re 1 1[micro]Pa) 
from 16 to 100 kHz, a frequency range that is much higher than noises 
generated from in-water pile driving, vessels, and pipe laying. 
Although not reported in their AEP study, audiograms provided in the 
paper show a rapid decrease in beluga whale hearing sensitivity as the 
frequencies get lower, like most odontocetes. Behavioral audiograms of 
beluga whales show that hearing sensitivity in the frequency below 1 
kHz is above 100 dB re 1 1[micro]Pa, and elevates to above 120 dB 
1[micro]Pa at about 100 Hz (White et al., 1978).
    In addition, CBD and Cook Inletkeeper are confused between the 
animals' detection thresholds and threshold of noise induced behavioral 
disturbances. Being able to detect the sound does not indicate that the 
animal would respond to the sound, much less be taken by Level B 
harassment, as defined under the MMPA. Studies show that animals 
usually respond to received noise at levels much higher than their 
hearing thresholds.
    Comment 16: CBD states that impacts of pile driving on beluga 
whales have been underestimated. CBD further states that pile driving 
[noise] could mask ``strong bottlenose dolphin vocalizations'' 10-15 km 
from the source (David, 2006).
    Response: NMFS has carefully reviewed the best available scientific 
information in assessing impacts to marine mammals and recognizes that 
these activities have the potential to impact marine mammals through 
threshold shifts, behavioral effects, stress responses, and auditory 
masking. However, NMFS has determined that the nature of such 
potentially localized exposure means that the likelihood of any impacts 
to fitness and population level disturbance from the authorized take, 
including from detrimental energetic effects or reproductive impacts, 
is low. NMFS has also prescribed a robust suite of mitigation measures, 
such as shutdown measures to avoid beluga Level B harassment, which is 
expected to further reduce both the number and severity of beluga whale 
takes.
    NMFS considers it highly unlikely that dolphin vocalizations could 
be masked by pile driving noise. As discussed in detail in the 
Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat section of the proposed rule, auditory masking occurs at the 
frequency band that the animals utilize. Since noise generated from 
vibratory pile driving is mostly concentrated at low frequency ranges 
below 2 kHz, it is expected to have minimal effects masking high 
frequency echolocation (clicks) and communication (whistles) sounds by 
odontocetes, including bottlenose dolphins. The analysis by David 
(2006) on masking is flawed as it did not adequately consider the 
frequency spectra of pile driving noise as it relates to auditory 
frequency response of the dolphin.
    Comment 17: CBD and Cook Inletkeeper claims that NMFS relied on 
avoidance [behavior] to make its negligible determination.
    Response: CBD's claim is inaccurate. NMFS did not rely on marine 
mammal avoidance behavior to make our negligible determination. To the 
contrary, NMFS considered avoidance as a form of Level B harassment. As 
stated clearly in the Proposed Rule (84 FR 39901; June 28, 2019), 
``marine mammals' exposure to certain sounds could lead to behavioral 
disturbance (Richardson et al., 1995), such as changing durations of 
surfacing and dives, number of blows per surfacing, or moving direction 
and/or speed; reduced/increased vocal activities; changing/cessation of 
certain behavioral activities (such as socializing or feeding); visible 
startle response or aggressive behavior (such as tail/fluke slapping or 
jaw clapping); avoidance of areas where noise sources are located; and/
or flight responses (e.g., pinnipeds flushing into water from haul-outs 
or rookeries).''
    Comment 18: CBD and Cook Inletkeeper state that NMFS failed to 
account for numerous harmful activities such as dredging, pipeline 
trenching, vessels transiting, and geophysical surveys that could 
result in takes of marine mammals.
    Response: As stated in the Proposed Rule (84 FR 39901; June 28, 
2019), dredging activity would occur during the construction of the 
Marine Terminal MOF using either a hydraulic (cutter head) dredger or a 
mechanical dredger, and pipeline trenching would occur in the Cook 
Inlet during pipeline laying operations. These activities typically 
have low noise levels (120-dB isopleths are typically within 150 m) and 
slow, predictable movement, which support the unlikelihood of resulting 
take. For example, URS (2007) measured underwater sound level was 141 
dB re 1 [mu]Pa rms at 12 m associated with U.S. Army Corps of Engineers 
(USACE) dredging activities at the Port of Alaska (formerly Port of 
Anchorage). The resulting 120-dB isopleths was 134.6 m. In addition, 
these activities are typically associated with slow moving barge/vessel 
and the noise output are intermittent. Nevertheless, NMFS considers how 
other activities associated with pipeline trenching, such as anchor 
handling that generates much louder noise, could cause takes of marine 
mammals. Effects from these activities have been analyzed and takes 
were estimated.
    Although noises generated from the vessel can be louder than 
dredging noise, similar to dredging, the movement is relatively 
predictable, and habituation to vessel traffic has been documented for 
some marine mammals in more industrialized areas. Therefore, we do not 
consider animals exposed to transiting vessels likely to respond in a 
manner that would rise to the level of a take as defined under the 
MMPA.
    The equipment AGDC proposed to use for its geophysical surveys are 
all high-frequency sources with frequencies above 200 kHz, as described 
in the Proposed Rule. These frequencies are beyond the detection 
thresholds of marine mammals. Therefore, NMFS does not expect operating 
these sources would have takes of marine mammals.
    Comment 19: CBD, Cook Inletkeeper, and FoA claim that the small 
numbers determination is flawed and that NMFS underestimated Cook Inlet 
beluga takes.
    Response: NMFS does not agree with CBD, Cook Inletkeeper, and FoA's

[[Page 50731]]

assessment. As described in details in the Proposed Rule (84 FR 39901; 
June 28, 2019), density estimates for Cook Inlet beluga were based on a 
habitat-based model developed by Goetz et al. (2012). Take estimates 
were calculated using the beluga whale densities in different areas of 
the Cook Inlet that overlap with the construction activities, taking 
into consideration ensonified areas and the duration of each activity. 
After the Proposed Rule was published, AGDC conducted additional 
analysis, which NMFS concurred was appropriate, using Goetz et al. 
(2012) modeled aerial survey data collected by NMFS between 1993 and 
2008 and developed beluga whale densities for each 1-square-kilometer 
cell of Cook Inlet. The calculation shows that the maximum annual take 
of Cook Inlet beluga whale, adjusted for group number is 13 animals. 
This translates to less than 5% of the Cook Inlet beluga whale stock's 
population.
    Regarding the small numbers determination, NMFS disagrees that it 
is flawed. NMFS refers the reader to the Federal Register Notice 
announcing NMFS' issuance of five IHAs authorizing take incidental to 
seismic surveys in the Atlantic (83 FR 63268; December 7, 2018), in 
which the agency describes in detail its method and rationale for 
determining whether take of marine mammals constitutes small numbers. 
As described in that notice, and in the associated sections of this 
notice, the small numbers determination and negligible impact analysis 
are conducted separately using entirely different approaches, although 
they necessarily consider some of the same biological information. 
Also, contrary to the commenter's assertion, NMFS has indicated that 
the determination of whether take of marine mammals is of small numbers 
is appropriately considered on an annual basis and the commenter has 
offered no justification for why this might not be appropriate.
    Comment 20: CBD and Cook Inletkeeper state that the proposed rule 
failed to ensure the least practicable adverse impact. Specifically, 
CBD and Cook Inletkeeper claimed that NMFS did not address the 
following issues: Limit on cumulative beluga whale takings in Cook 
Inlet; time-area restrictions; larger exclusion zones; air curtains or 
other noise reduction technologies; and sound source verification.
    Response: NMFS does not agree with CBD and Inletkeeper's assertion. 
As described in the Proposed Rule (84 FR 39901; June 28, 2019), NMFS 
worked with AGDC and proposed a wide range of monitoring and mitigation 
to achieve the least practicable adverse impact. These measures 
included, but were not limited to: (1) Limiting in-water pile driving 
activities to daylight hours only; (2) implementing shutdown measures 
for beluga whales to prevent Level A harassment of this species; (3) 
implementing soft start for all impact pile driving; and (4) monitoring 
both Level A and Level B harassment zones to ensure takes does not 
exceed the number or species that would not be authorized. NMFS has 
described why these measures, along with monitoring and mitigation 
measures described in the proposed rule, will ensure the least 
practicable adverse impacts to AGDC's LNG facility construction 
project. After the Proposed Rule was published, NMFS further worked 
with AGDC to identify additional practicable measures and included the 
following additional mitigation and monitoring measures: (1) 
Prohibiting in-water pile driving near beluga whale summer feeding 
ground between June 1 and September 7 in west Cook Inlet; (2) 
implementing larger exclusion zones for shutdown measures to prevent/
reduce Level B harassment of Cook Inlet beluga whales; (3) implementing 
shutdown measure to prevent Level A harassment of all mid-frequency 
cetaceans; (4) implement shutdown measures to reduce Level A takes of 
all other marine mammals; (5) requiring AGDC to conduct passive 
acoustic monitoring to assess the range of ensonified zones; (6) 
requiring AGDC to assess the effectiveness of air bubble curtains by 
conducting sound source verification; and (7) requiring AGDC to deploy 
air bubble curtains to reduce pile driving noise level if the air 
bubble curtains are found to be able to achieve a noise reduction of 2 
dB or more. These additional monitoring and mitigation measures address 
four out of the five concerns raised by CBD and Cook Inletkeeper. 
Regarding CBD and Cook Inletkeeper's comments on limiting cumulative 
beluga whale takes in Cook Inlet, NMFS addressed this in Response to 
Comments 2 and 3 above. Additionally, for the issuance of the LOA, our 
analysis showed that at a maximum, 14 Cook Inlet beluga whales could be 
exposed to noise levels that result to Level B harassment in a given 
year without any mitigation measures in place. This number equates to 
5% of the Cook Inlet beluga whale population. Implementation of 
required monitoring and mitigation are likely to further reduce the 
severity and number of takes of Cook Inlet beluga whale.
    Comment 21: CBD and Cook Inletkeeper claims that NMFS finding of no 
unmitigable impacts on subsistence harvest is arbitrary because the 
proposed action may have an adverse impact on the availability of 
beluga whales, harbor seals, Steller sea lions, and sea otters for 
Native Alaskan subsistence harvest.
    Response: NMFS does not agree with CBD and Cook Inletkeeper's 
assertion. First, there is no subsistence harvest of Cook Inlet beluga 
whales because of its low population in more than a decade. The 
criteria established for when subsistence hunt of Cook Inlet beluga 
could resume included the need for a ten-year average abundance 
estimate to exceed 350 animals, as well as a requirement for an 
increasing population trajectory; therefore, there are no active 
subsistence uses of beluga whales that the activity could interfere 
with. Further, as described in this notice, the Level B harassment take 
of beluga whales allowed through these regulations would be of small 
numbers and of a low degree not expected to effect the fitness, 
reproduction, or survival of any individuals, and therefore would not 
impede the recovery of the population or otherwise affect the ten-year 
abundance average. In regard to other marine mammal species, NMFS 
conducted a thorough analysis on substance use of these species. Jones 
and Kostick (2016) reported that 2 percent of households in Nikiski, 
the closest village to AGDC's proposed project area, used harbor seals 
and 1 percent reported using unknown seal species (both gifted from 
another region). No marine mammals were actively hunted by Alaska 
Native residents in Nikiski. There is limited use of marine mammals 
thought to be from the small number of Alaska Natives living in Nikiski 
(Jones and Kostick, 2016). In other locations, the hunt of marine 
mammals is conducted opportunistically and at such a low level that 
totals approximately 50 harbor seals and fewer than 10 Steller sea 
lions in a typical year. Therefore, AGDC's program is not expected to 
have an impact on the subsistence use of marine mammals.
    Nevertheless, NMFS required AGDC to develop a stakeholder 
engagement plan and communicate with subsistence users in the region to 
inform its proposed activities.
    Comment 22: CBD and Cook Inletkeeper claim the draft Environmental 
Impact Statement (EIS) is flawed based on the assertion that (1) the 
purpose and need are too narrowly defined; (2) NMFS failed to consider 
a reasonable range of alternatives related to mitigation measures; and 
(3) the discussion of environmental and cumulative impacts of the 
proposed

[[Page 50732]]

project is inadequate as it does not discuss the planned oil and gas 
lease sales, the Hilcorp seismic survey and exploratory drilling, and 
Pebble Mine.
    Response: NMFS does not agree with CBD and Cook Inletkeeper's 
assertions. First, NMFS worked with the Federal Energy Regulatory 
Commission (FERC) and clarified NMFS' responsibility in the ``Purpose 
and Scope of This EIS'' section of the final EIS. Specifically, the EIS 
states that NMFS, in accordance with 40 CFR 1506.3 and 1505.2, intends 
to adopt this EIS and issue a separate record of decision (ROD) 
associated with its decision to grant or deny AGDC's request for 
regulations and a Letter of Authorization (LOA) pursuant to Section 
101(a)(5)(A) of the MMPA for construction activities in Cook Inlet.
    In regard to the range of alternatives being considered, NMFS 
worked with FERC and required a suite of monitoring and mitigation 
measures that are the most protective to ensure the least practicable 
adverse impact. While a range of alternatives concerning the scope of 
the project were presented in the EIS, many of these project-related 
alternatives were eliminated either due to no environmental advantage 
or impracticable for the project and were eliminated.
    Finally, we note that the projects that CBD and Cook Inletkeeper 
note (planned oil and gas lease sales, the Hilcorp seismic survey and 
exploratory drilling, and Pebble Mine) are all discussed in the 
Cumulative Impacts of the final EIS (pages 4-1188 and 4-1189 of the 
FEIS). The first two projects are also shown in a map on page 4-1168 of 
the FEIS, while the site of Pebble Mine is outside the vicinity of 
AGDC's proposed project area in Cook Inlet.
    Comment 23: CBD and Cook Inletkeeper states that NMFS should not 
issue take authorization under the Endangered Species Act (ESA).
    Response: NMFS disagree with CBD and Cook Inletkeeper's opinion. As 
stated in Response to Comment 1, NMFS is required to issue a marine 
mammal incidental take authorization for a specified activity within 
the specified geographic region if NMFS is able to determine that the 
activity will have a negligible impact on the species or stock and will 
not have an unmitigable adverse impact on the availability of such 
species or stock for subsistence uses. Based on the scientific evidence 
available, NMFS determined that the impacts of the AGDC LNG facility 
construction activities meet these standards.
    Regarding ESA compliance for the NMFS authorization (under the 
MMPA) of ESA-listed species such the Cook Inlet beluga whale and 
Western North Pacific, Hawaii, and Mexico DPS of humpback whales, NMFS' 
Permit and Conservation Division requested initiation of section 7 
consultation with the Alaska Region for the promulgation of 5-year 
regulations and the subsequent issuance of annual LOAs. The Alaska 
Region issued a Biological Opinion concluding that NMFS' action is not 
likely to adversely affect the listed species named above or adversely 
modify their critical habitat.
    Comment 24: FoA states that the proposed project would create noise 
pollution that is likely to cause hearing damage to Cook Inlet beluga 
whales.
    Response: NMFS does not agree with FoA's assertion. While FoA did 
not define what constitute to ``noise pollution,'' NMFS provided an in-
depth analysis on noise generated from AGDC's proposed LNG facility 
construction. Based on the analysis, NMFS finds it extremely unlikely 
that a beluga whale would experience hearing damage (permanent 
threshold shift) from the proposed AGDC construction activity. The 
analysis is supported by scientific information presented in NMFS' 
Technical Guidance for Assessing the Effects of Anthropogenic Sound on 
Marine Mammal Hearing (V.2.0) (NMFS, 2016; 2018) and based on density 
estimate of Cook Inlet beluga whales in the project area, ensonified 
area and noise exposure duration from construction activities. Our 
analysis showed that anticipated takes of Cook Inlet beluga whales are 
expected to be limited to short-term Level B harassment. Beluga whales 
present in the vicinity of the action area and taken by Level B 
harassment would most likely show overt brief disturbance (startle 
reaction) and avoidance of the area from elevated noise levels during 
pile driving.
    Comment 25: FoA states that the proposed project is susceptible to 
catastrophic events, such as oil spill, which is reasonably likely to 
negatively impact the species.
    Response: Oil spills are not considered because take of marine 
mammals due to oil spills are not anticipated or authorized. AGDC is 
required to comply with all regulations related to pileline laying and 
vessel transiting and is responsible for ensuring its compliance with 
those regulations. An oil spill, or a violation of other federal 
regulations, is not authorized under this rule.
    Comment 26: FoA claims that NMFS' issuance of the LOA would violate 
the NEPA, and that NMFS should prepare a Programmatic EIS (PEIS).
    Response: NMFS originally declared its intent to prepare a PEIS for 
oil and gas activities in Cook Inlet, Alaska (79 FR 61616; October 14, 
2014). However, in a 2017 Federal Register notice (82 FR 41939; 
September 5, 2017), NMFS indicated that due to a reduced number of 
Incidental Take Authorization (ITA) requests in the region, combined 
with funding constraints at that time, we were postponing any potential 
preparation of a PEIS for oil and gas activities in Cook Inlet. As 
stated in the 2017 Federal Register notice, should the number of ITA 
requests, or anticipated requests, noticeably increase, NMFS will re-
evaluate whether preparation of a PEIS is necessary. Currently, the 
number of ITA requests for activities that may affect marine mammals in 
Cook Inlet is at such a level that preparation of a PEIS is not yet 
necessary. Nonetheless, under NEPA, NMFS is required to consider 
cumulative effects of other potential activities in the same geographic 
area, and these are discussed in greater detail in FERC's Alaska LNG 
Project Final Environmental Impact Statement (FERC, 2020), which NMFS 
adopted.
    Comment 27: DoW requests NMFS defer the comment period for the 
Proposed Rule until later in the EIS process, when additional relevant 
information could be available for NMFS and public review, or reopen a 
public comment period before finalizing the rulemaking on its own 
determination that additional relevant information has become 
available.
    Response: When evaluating the AGDC's petition to take marine mammal 
incidental to its proposed construction of LNG facilities in Cook 
Inlet, Alaska, NMFS has conducted thorough review of the scope of the 
proposed activities and the level of potential impacts to marine 
mammals. In doing so, NMFS consulted internally with its experts who 
have the best scientific information on the species and their habitat. 
A Proposed Rule is published for public comment only when NMFS is 
convinced that it has all relevant information to conduct the impact 
analyses to support preliminary findings pursuant to the statutory 
standards. While the NEPA analysis will be finalized at a later time, 
since NMFS is a cooperating agency on the FERC's EIS, NMFS reviewed all 
the public comments from the EIS as well to inform its final decision. 
Therefore, in this case, NMFS does not believe there was a need to 
defer the public comment period, or reopen a public comment period 
before finalize the rulemaking.
    Comment 28: DoW states that NMFS' proposed rule did not consider

[[Page 50733]]

operational noise associated with the proposed LNG facilities. Citing 
FERC's DEIS, DoW states that the highest noise levels would occur when 
there are two LNG carrier ships docked at the facility. DoW states that 
NMFS should include this additional noise in its analysis.
    Response: The action being considered here is the issuance of a 
Letter of Authorization under a rulemaking for the incidental take of 
small numbers of marine mammals that could result from AGDC's proposed 
construction of LNG facilities in Cook Inlet. Our action does not 
include the operation of LNG carrier ships in the future. Therefore, 
potential impacts to marine mammals beyond what were analyzed for 
AGDC's proposed LNG facilities construction activities were not 
analyzed, and any takes caused by those activities are not authorized.
    Comment 29: DoW claims that twelve hours of noise exposure every 
day from April through October and the take of 7% Cook Inlet beluga 
whales should not be considered a negligible impact.
    Response: NMFS does not agree with DoW's conclusion and nor are the 
assumptions upon which it is based accurate. First, while some of the 
pile driving activities may occur twelve hours per day, construction 
activities are expected to be conducted six days a week from April 
through October. In addition, not all construction activities generate 
intense underwater noise, and most of the in-water pile driving 
activities would not last for 12 hours per day. Furthermore, as marine 
mammals move around Cook Inlet, animals would only be exposed to in-
water construction noise when they are present in the area. Finally, 
the negligible impact determination considers relevant biological and 
contextual factors, i.e., the anticipated impacts to the individuals 
and the stock, of the take authorized, as described in details in the 
Proposed Rule (84 FR 39901; June 28, 2019).
    Comment 30: The EIA expressed concern about potential renewal of 
the proposed incidental take authorization (IHA).
    Response: NMFS does not propose to issue nor renew an IHA to AGDC 
for the proposed LNG facility construction in Cook Inlet. EIA may be 
confused with NMFS proposed issuance of an LOA under a 5-year 
regulation. The regulations are valid for five years from the date of 
issuance with a maximum of a five-year Letter of Authorization 
requested under these regulations. If AGDC wanted to pursue marine 
mammal take authorization beyond the effective period of these 
regulations, they would need to apply anew for an IHA or LOA.
    Comment 31: EIA is concerned that it was not able to comment on the 
updated version of the LOA application until July 24, 2019, and that 
the only application available was a previous version dated February 
20, 2019. EIA further states that it was difficult to evaluate the 
project's impact, because the activities described in both documents 
are roughly similar for each season and estimates rely on the same 
research for each density estimate, but NMFS estimated a total of 14 
beluga takes from Level B harassments from 2020-2025, while AGDC 
estimated 10 belugas but in different seasons.
    Response: While reviewers were mistakenly not provided the most up-
to-date version of the application, the scope of the project and 
analytical methods were accurately described and remained the same in 
later versions. In AGDC's LOA application, it estimated a total of 10 
Cook Inlet beluga whale noise exposure by Level B harassment over the 
5-year period of the activity but requested for an annual take of 32 
animals. In NMFS' analysis, which is using the same methods, we 
proposed an annual take of 20 beluga whales based on exposure analysis 
that is adjusted to account for group size.

Changes Between Proposed Rule and Final Rule

    Several changes were made after the publication of the proposed 
rule on June 28, 2019 (84 FR 39931). Those changes resulted from 
updated marine mammal density and population information, more detailed 
analyses on potential impacts using refined data sets, and additional 
mitigation and monitoring measures to minimize impacts. The changes 
between proposed and final rules are summarized below.
    Authorized takes of marine mammal species were reduced from 10 
species to 5 species. In the proposed rule, NMFS proposed to authorize 
takes of humpback whale, fin whale, gray whale, beluga whale, killer 
whale, harbor porpoise, Dall's porpoise, harbor seal, California sea 
lion, and Steller sea lion. In the final rule, takes of fin whale, gray 
whale, Dall's porpoise, California sea lion, and Steller sea lion are 
not authorized because data show that they are not likely to be present 
and exposed to the construction activities (see Description of Marine 
Mammals in the Area of Specified Activities section below).
    Take numbers of marine mammals were updated based on the newest 
information on population estimates and refined density modeling. 
Marine mammal density data in the proposed rule were based on NMFS 
aerial survey in Cook Inlet from 2000 to 2016. In the final rule, 
additional density from the 2018 aerial survey were also included. In 
addition, Cook Inlet beluga whale density was further updated based on 
the latest population estimated that became available in January 2020 
(NMFS, 2020), and the take estimate for this species was reanalyzed 
using a more refined density grid than what was used for the proposed 
rule. The take number for harbor seals was adjusted based on comments 
from the Commission and consultation with NMFS National Marine Mammal 
Laboratory.
    The final rule also included additional monitoring and mitigation 
measures to further reduce potential impacts to marine mammals. Many of 
these measures are based on consideration of public comments. These 
additional monitoring and mitigation measures include:
     Implementing time/area restriction to minimize potential 
noise exposure to Cook Inlet beluga whales in the Susitna River Delta;
     Implementing larger exclusion zones for all in-water 
construction activities to prevent or reduce Level A harassment for all 
marine mammals and to prevent Level B harassment for Cook Inlet beluga 
whales;
     Requiring sound source verification (SSV) measurement for 
in-water pile driving to better understand underwater noise generated 
from pile driving activities; and
     Deploying air bubble curtains to attenuate noise from in-
water pile driving if SSV results show a 2-dB reduction of noise from 
air bubble curtains.

Description of Marine Mammals in the Area of Specified Activities

    Sections 4 and 5 of the IHA 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' Stock Assessment Reports (SARs; 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS' 
website (www.fisheries.noaa.gov/find-species).
    Five species that were analyzed in the Proposed Rule (84 FR 39901; 
June 28, 2019) but since were removed in the

[[Page 50734]]

final analysis due to their extralimital presence in the proposed area, 
based on in depth analysis of NMFS marine mammal aerial survey data 
(summarized in Shelden et al., 2017; 2019). These species are: Fin 
whale (Balaenoptera physalus), gray whale (Eschrichtius robustus), 
Dall's porpoise (Phocoenoides dali), California sea lion (Zalophus 
californianus), and Steller sea lion (Eumetopias jubatus). As take of 
these species is not anticipated as a result of the proposed 
activities, these species are not analyzed further in this document.
    Table 3 summarizes information related to the population or stock, 
including regulatory status under the MMPA and ESA and potential 
biological removal (PBR), where known. For taxonomy, we follow 
Committee on Taxonomy (2019). 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 is 
included here as a gross indicator of the status of the species and 
other threats.

                                         Table 3--Marine Mammals With Potential Presence Within the Project Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/MMPA status;    Stock abundance (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenopteridae:
    Humpback whale..................  Megaptera novaneagliae.  Western North Pacific..  E/D; Y              1,107 (0.300, 865)....        3.0        2.6
Family Delphinidae:
    Killer whale....................  Orcinus orca...........  Eastern North Pacific    -; N                2,347 (NA, 2,347).....         24          1
                                                                Alaska Resident.
    Beluga whale \4\................  Delphinapterus leucas..  Cook Inlet.............  E/D; Y              279 (0.06, NA)........        unk          0
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  Gulf of Alaska.........  -; N                31,046 (2.14, NA).....        unk         72
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Harbor seal.....................  Phoca vitulina.........  Cook Inlet/Shelikof      -; N                28,411 (NA, 26,907)...        807        107
                                                                Strait.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region#reports. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
  fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated
  with estimated mortality due to commercial fisheries is presented in some cases.
\4\ Cook Inlet beluga whale population estimates are updated based on Sheldon et al. (2019).

    Marine mammal species that could potentially occur in the proposed 
construction areas are included in Table 3. Detailed discussion of 
these species is provided in the LOA application and summary 
information is provided below.
    In addition, sea otters may be found in Cook Inlet. However, sea 
otters are managed by the U.S. Fish and Wildlife Service and are not 
considered further in this document.

Humpback Whale

    The humpback whale is distributed worldwide in all ocean basins. In 
winter, most humpback whales occur in the subtropical and tropical 
waters of the Northern and Southern Hemispheres. Humpback whales in the 
high latitudes of the North Pacific Ocean are seasonal migrants that 
feed on euphausiids and small schooling fishes (Nemoto, 1957, 1959; 
Clapham and Mead, 1999). The humpback whale population was considerably 
reduced as a result of intensive commercial exploitation during the 
20th century.
    The historical summer feeding range of humpback whales in the North 
Pacific encompassed coastal and inland waters around the Pacific Rim 
from Point Conception, California, north to the Gulf of Alaska and the 
Bering Sea, and west along the Aleutian Islands to the Kamchatka 
Peninsula and into the Sea of Okhotsk and north of the Bering Strait 
(Zenkovich, 1954; Nemoto, 1957; Tomlin, 1967; Johnson and Wolman, 
1984). Historically, the Asian wintering area extended from the South 
China Sea east through the Philippines, Ryukyu Retto, Ogasawara Gunto, 
Mariana Islands, and Marmust Islands (Rice, 1998). Humpback whales are 
currently found throughout this historical range. Most of the current 
winter range of humpback whales in the North Pacific is relatively well 
known, with aggregations of whales in Japan, the Philippines, Hawaii, 
Mexico, and Central America. The winter range includes the main islands 
of the Hawaiian archipelago, with the greatest concentration along the 
west side of Maui. In Mexico, the winter breeding range includes waters 
around the southern part of the Baja California peninsula, the central 
portions of the Pacific coast of mainland Mexico, and the Revillagigedo 
Islands off the mainland coast. The winter range also extends from 
southern Mexico into Central America, including Guatemala, El Salvador, 
Nicaragua, and Costa Rica (Calambokidis et al., 2008).
    Although there is considerable distributional overlap in the 
humpback whale stocks that use Alaskan waters, the whales seasonally 
found in lower Cook Inlet are probably of the Central North Pacific 
stock (Barlow et al., 2011; Allen and Angliss 2015).
    Humpback whale use of Cook Inlet has been observed to be confined 
to Lower Cook Inlet; the whales have been regularly seen near Kachemak 
Bay during the summer months (Rugh et al., 2005). There are anecdotal 
observations of humpback whales as far north as Anchor Point, with 
recent summer observations extending to Cape Starichkof (Owl Ridge, 
2014). Humpback whales will move about their

[[Page 50735]]

range. It is possible for a small number of humpback whales to be 
observed near the Marine Terminal construction area, but they are 
unlikely to venture north into the proposed Upper Cook Inlet pipeline 
crossings.

Killer Whale

    Killer whales are widely distributed, although they occur in higher 
densities in colder and more productive waters (Allen and Angliss, 
2015). Two different stocks of killer whales inhabit the Cook Inlet 
region: The Alaska Resident Stock and the Gulf of Alaska, Aleutian 
Islands, Bering Sea Transient Stock (Allen and Angliss, 2015).
    Killer whales are occasionally observed in Lower Cook Inlet, 
especially near Homer and Port Graham (Shelden et al., 2003; Rugh et 
al., 2005). A concentration of sightings near Homer and inside Kachemak 
Bay may represent high use, or high observer-effort given most records 
are from a whale-watching venture based in Homer. The few whales that 
have been photographically identified in Lower Cook Inlet belong to 
resident groups more commonly found in nearby Kenai Fjords and Prince 
William Sound (Shelden et al., 2003). Prior to the 1980s, killer whale 
sightings in Upper Cook Inlet were very rare (Rugh et al., 2005). 
During aerial surveys conducted between 1993 and 2004, killer whales 
were observed on only three flights, all in the Kachemak and English 
Bay area (Rugh et al., 2005). However, anecdotal reports of killer 
whales feeding on belugas in Upper Cook Inlet began increasing in the 
1990s, possibly in response to declines in sea lions and harbor seals 
elsewhere (Shelden et al., 2003). Observations of killer whales in 
beluga summering grounds have been implicated as a possible contributor 
to decline of Cook Inlet belugas in the 1990s, although the number of 
confirmed mortalities from killer whales is small (Shelden et al., 
2003). Recent industry monitoring programs only reported a few killer 
whale sightings (Kendall et al., 2015). The sporadic movements and 
small numbers of this species suggest that there is a rare possibility 
of encountering this whale during Marine Terminal construction and 
Mainline pipe laying. There is, however, a greater possibility of 
transiting vessels associated with the Project encountering killer 
whales during transit through Lower Cook Inlet.

Beluga Whale

    The Cook Inlet beluga whale distinct population segment (DPS) is a 
small, geographically isolated, and genetically distanced population 
separated from other beluga populations by the Alaska Peninsula 
(O'Corry-Crowe et al., 1997). The Cook Inlet beluga DPS was originally 
estimated at 1,300 whales in 1979 (Calkins, 1989) and has been the 
focus of management concerns since experiencing a dramatic decline 
between 1994 and 1998, when the stock declined 47 percent, attributed 
to overharvesting by subsistence hunting (Mahoney and Shelden, 2000). 
Prior to subsistence hunting restrictions, harvest was estimated to 
annually remove 10 to 15 percent of the population (Mahoney and 
Shelden, 2000). Only five belugas have been harvested since 1999, yet 
the population has continued to decline. NMFS listed the population as 
``depleted'' in 2000 because of the decline, and as ``endangered'' 
under the ESA in 2008 when the population failed to recover following a 
moratorium on subsistence harvest.
    In April 2011, NMFS designated critical habitat for Cook Inlet 
beluga whales (76 FR 20180; April 11, 2011) in two specific areas of 
Cook Inlet:
     Area 1: All marine waters of Cook Inlet north of a line 
from the mouth of Threemile Creek (61[deg]08.5' N, 151[deg]04.4' W) 
connecting to Point Possession (61[deg]02.1' N, 150[deg]24.3' W), 
including waters of the Susitna River south of 61[deg]20.0' N, the 
Little Susitna River south of 61[deg]18.0' N, and the Chickaloon River 
north of 60[deg]53.0' N; and
     Area 2: All marine waters of Cook Inlet south of a line 
from the mouth of Threemile Creek (61[deg]08.5' N, 151[deg]04.4' W) to 
Point Possession (61[deg]02.1' N, 150[deg]24.3' W) and north of 
60[deg]15.0' N, including waters within 2 nautical miles seaward of 
mean-high high water (MHHW) along the western shoreline of Cook Inlet 
between 60[deg]15.0' N and the mouth of the Douglas River (59[deg]04.0' 
N, 153[deg]46.0' W); all waters of Kachemak Bay east of 151[deg]40.0' 
W; and waters of the Kenai River below the Warren Ames bridge at Kenai, 
Alaska.
    The Cook Inlet beluga whale population is estimated to have 
declined from 1,300 animals in the 1970s (Calkins, 1989) to about 340 
animals in 2014 (Shelden et al., 2015). The current population estimate 
is 279 animals (Shelden et al., 2019). The precipitous decline 
documented in the mid-1990s was attributed to unsustainable subsistence 
practices by Alaska Native hunters (harvest of more than 50 whales per 
year) (Mahoney and Shelden, 2000). In 2006, a moratorium of the harvest 
of Cook Inlet beluga whales was agreed upon through a cooperative 
agreement between the Cook Inlet Marine Mammal Council and NMFS.
    During late spring, summer, and fall, beluga whales concentrate 
near the Susitna River mouth, Knik Arm, Turnagain Arm, and Chickaloon 
Bay (Nemeth et al., 2007) where they feed on migrating eulachon and 
salmon (Moore et al., 2000). Critical Habitat Area 1 reflects this 
summer distribution. During winter, beluga whales concentrate in deeper 
waters in the mid-inlet to Kalgin Island, and in the waters along the 
west shore of Cook Inlet to Kamishak Bay. Although belugas may be found 
throughout Cook Inlet at any time of year, they generally spend the 
ice-free months in Upper Cook Inlet and expand their distribution south 
and into more offshore waters of Upper Cook Inlet in winter. These 
seasonal movements appear to be related to changes in the physical 
environment from sea ice and currents and shifts in prey resources 
(NMFS, 2016). Belugas spend most of their time year-round in the 
coastal areas of Knik Arm, Turnagain Arm, Susitna Delta, Chickaloon 
Bay, and Trading Bay (Goetz et al., 2012). During the open-water months 
in Upper Cook Inlet (north of the Forelands), beluga whales are 
typically concentrated near river mouths (Rugh et al., 2010).
    Satellite tags from 10 whales tagged from 2000 through 2002 
transmitted through the fall, and of those, three tags deployed on 
adult males transmitted through April and late May. None of the tagged 
beluga moved south of Chinitna Bay on the western side of Cook Inlet. A 
review of marine mammal surveys conducted in the Gulf of Alaska from 
1936 to 2000 discovered only 31 beluga sightings among 23,000 marine 
mammal sightings, indicating that very few belugas occur in the Gulf of 
Alaska outside of Cook Inlet (Laidre et al., 2000 cited in Allen and 
Angliss, 2014).
    Based on these studies, it is anticipated that beluga whales are 
most likely to occur near the Marine Terminal in moderate densities 
during the period when sea ice is typically present in Cook Inlet north 
of the Forelands (December through May; Goetz et al., 2012). Few 
belugas may occur near the Marine Terminal during the ice-free period 
(June through November). Belugas would not be expected to focus their 
foraging (dive) efforts near the proposed Marine Terminal location. If 
belugas do forage near the Marine Terminal, their foraging dives are 
more likely to be long and deep during the sea-ice season (December 
through May; Goetz et al., 2012).
    Beluga whales could be found in the vicinities of the Mainline 
crossing during summer-fall and the Marine Terminal construction area 
during

[[Page 50736]]

winter. Previous marine mammal surveys conducted between the Beluga 
River and the West Forelands (Nemeth et al., 2007; Brueggeman et al., 
2007a, b; Lomac-MacNair et al., 2013, 2014; Kendall et al., 2015) 
suggest that beluga whale numbers near the proposed Mainline MOF on the 
west side of Cook Inlet and the pipeline landing peak in May and again 
in October, with few whales observed in the months in between.
    Beluga whales are expected to occur along the entire portion of the 
Mainline route within Upper Cook Inlet year-round; but, as discussed 
previously, beluga distribution is concentrated in mustow coastal 
waters near Knik Arm, Chickaloon Bay, and Trading Bay during the ice-
free season (June through November), and in deeper waters of the 
Susitna Delta, and offshore between East and West Forelands, and around 
Fire Island during the sea-ice season (December through May) (Goetz et 
al., 2012). Belugas may remain near the Mainline route during the 
winter (December through May).
    Belugas forage in the Trading Bay area from June to through 
November (Goetz et al., 2012). Belugas may remain near the Mainline 
route during the winter (December through May) (Goetz et al., 2012). 
Belugas would be expected to focus their foraging (dive) efforts near 
the Trading Bay area during June to November, south of where the 
proposed Mainline would enter Cook Inlet.

Harbor Porpoise

    The Gulf of Alaska harbor porpoise stock is distributed from Cape 
Suckling to Unimak Pass (Allen and Angliss, 2015). They are found 
primarily in coastal waters less than 328 feet deep (Hobbs and Waite, 
2010) where they feed on Pacific herring (Clupea pallasii), other 
schooling fishes, and cephalopods.
    Although harbor porpoises have been frequently observed during 
aerial surveys in Cook Inlet, most sightings are of single animals, and 
the sightings have been concentrated nearshore between Iliamna and 
Tuxedni bays on the lower west side of Lower Cook Inlet (Rugh et al., 
2005; Shelden et al., 2013). No harbor porpoises were recorded near 
Nikiski during NMFS aerial surveys conducted between 1993 and 2012 
(Shelden et al., 2013). Dahlheim et al. (2000) estimated the 1991 Cook 
Inlet-wide population at 136 animals. However, they are one of the 
three marine mammals (besides belugas and harbor seals) regularly seen 
in Upper Cook Inlet (Nemeth et al., 2007), especially during spring 
eulachon and summer salmon runs. Brueggeman et al. (2007a, b) also 
reported small numbers of harbor porpoise between Granite Point and the 
Beluga River. Recent industry monitoring programs in Lower and Middle 
Cook Inlet reported harbor porpoise sightings in all summer months 
(Lomac-MacNair et al., 2013, 2014; Kendall et al., 2015). Because 
harbor porpoise have been observed throughout Cook Inlet during the 
summer months, they represent a species that could be encountered 
during all phases and locations of construction.

Harbor Seal

    Harbor seals inhabit coastal and estuarine waters along the West 
Coast, including southeast Alaska west through the Gulf of Alaska and 
Aleutian Islands, in the Bering Sea and Pribilof Islands (Allen and 
Angliss, 2015). At more than 150,000 animals state-wide, harbor seals 
are one of the more common marine mammal species in Alaskan waters 
(Allen and Angliss, 2015). Harbor seals haul out on rocks, reefs, 
beaches, and drifting glacial ice (Allen and Angliss, 2015).
    Large numbers of harbor seals concentrate at the river mouths and 
embayments of Lower Cook Inlet, including the Fox River mouth in 
Kachemak Bay (Rugh et al., 2005). Montgomery et al. (2007) recorded 
over 200 haulout sites in Lower Cook Inlet alone. However, only a few 
hundred seals seasonally occur in Upper Cook Inlet (Rugh et al., 2005; 
Shelden et al., 2013), mostly at the mouth of the Susitna River where 
their numbers vary in concert with the spring eulachon and summer 
salmon runs (Nemeth et al., 2007; Boveng et al., 2012). In 2012, up to 
83 harbor seals were observed hauled out at the mouths of the Theodore 
and Lewis rivers during April to May monitoring activity associated 
with a Cook Inlet seismic program (Brueggeman, 2007a). Montgomery et 
al. (2007) also found seals elsewhere in Cook Inlet to move in response 
to local steelhead (Onchorhynchus mykiss) and salmon runs. Recent 
industry monitoring programs in Lower and Middle Cook Inlet reported 
harbor seal sightings in all summer months, both in-water and on 
haulouts (Lomac-MacNair et al., 2013, 2014; Kendall et al., 2015). 
During summer, small numbers of harbor seals are expected to occur near 
the Marine Terminal construction area near Nikiski, and along the 
proposed Mainline pipeline crossing route.

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 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. The functional groups and the associated 
frequencies are indicated below (note that these frequency ranges 
correspond to the range for the composite group, with the entire range 
not necessarily reflecting the capabilities of every species within 
that group):
     Low-frequency cetaceans (mysticetes): Generalized hearing 
is estimated to occur between approximately 7 Hz and 35 kHz;
     Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Generalized hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; including two members 
of the genus Lagenorhynchus, on the basis of recent echolocation data 
and genetic data): Generalized hearing is estimated to occur between 
approximately 275 Hz and 160 kHz;
     Pinnipeds in water; Phocidae (true seals): Generalized 
hearing is estimated to occur between approximately 50 Hz to 86 kHz; 
and
     Pinnipeds in water; Otariidae (eared seals): Generalized 
hearing is estimated to occur between 60 Hz and 39 kHz.
    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating

[[Page 50737]]

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 (2016) for a review of available information. 
Five marine mammal species (4 cetacean and 1 pinniped (phocid) 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, one species is classified as low-frequency 
cetaceans (i.e., humpback whale), two are classified as mid-frequency 
cetaceans (killer and beluga whales), and one is classified as high-
frequency cetaceans (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 by Incidental Harassment section 
later in this document includes a quantitative analysis of the number 
of individuals that are expected to be taken by this activity. The 
Negligible Impact Analysis and Determination section considers the 
content of this section, the Estimated Take by Incidental Harassment 
section, and the Mitigation section, to draw conclusions regarding the 
likely impacts of these activities on the reproductive success or 
survivorship of individuals and how those impacts on individuals are 
likely to impact marine mammal species or stocks.
    Potential impacts to marine mammals from the Alaska LNG project are 
from noise generated during in-water pile driving and anchor handling 
activities.

Acoustic Effects

    Acoustic effects to marine mammals from the proposed Alaska LNG 
facilities construction mainly include behavioral disturbances and 
temporary masking of animals in the area. A few individual animals 
could experience mild levels of temporary and/or permanent hearing 
threshold shift.
    The AGDC's LNG facilities construction project using in-water pile 
driving and anchor handling during trenching and pipe laying could 
adversely affect marine mammal species and stocks by exposing them to 
elevated noise levels in the vicinity of the activity area.
    Threshold Shift (noise-induced loss of hearing)--Exposure to high 
intensity sound for a sufficient duration may result in auditory 
effects such as a noise-induced threshold shift (TS)--an increase in 
the auditory threshold after exposure to noise (Finneran et al., 2005). 
Factors that influence the amount of threshold shift include the 
amplitude, duration, frequency content, temporal pattern, and energy 
distribution of noise exposure. The magnitude of hearing threshold 
shift normally decreases over time following cessation of the noise 
exposure. The amount of TS just after exposure is the initial TS. If 
the TS eventually returns to zero (i.e., the threshold returns to the 
pre-exposure value), it is a temporary threshold shift (TTS) (Southall 
et al., 2007). When animals exhibit reduced hearing sensitivity (i.e., 
sounds must be louder for an animal to detect them) following exposure 
to an intense sound or sound for long duration, it is referred to as a 
noise-induced TS. An animal can experience TTS or permanent threshold 
shift (PTS). TTS can last from minutes or hours to days (i.e., there is 
complete recovery), can occur in specific frequency ranges (i.e., an 
animal might only have a temporary loss of hearing sensitivity between 
the frequencies of 1 and 10 kHz), and can be of varying amounts (for 
example, an animal's hearing sensitivity might be reduced initially by 
only 6 dB or reduced by 30 dB). PTS is permanent, but some recovery is 
possible. PTS can also occur in a specific frequency range and amount 
as mentioned above for TTS.
    For marine mammals, published data are limited to the captive 
bottlenose dolphin, beluga, harbor porpoise, and Yangtze finless 
porpoise (Finneran, 2015). For pinnipeds in water, data are limited to 
measurements of TTS in harbor seals, an elephant seal, and California 
sea lions (Kastak et al., 1999, 2005; Kastelein et al., 2012b).
    Lucke et al. (2009) found a TS of a harbor porpoise after exposing 
it to airgun noise with a received sound pressure level (SPL) at 200.2 
dB (peak-to-peak) re: 1 micropascal ([mu]Pa), which corresponds to a 
sound exposure level (SEL) of 164.5 dB re: 1 [mu]Pa\2\ s after 
integrating exposure. Because the airgun noise is a broadband impulse, 
one cannot directly determine the equivalent of root mean square (rms) 
SPL from the reported peak-to-peak SPLs. However, applying a 
conservative conversion factor of 16 dB for broadband signals from 
seismic surveys (McCauley, et al., 2000) to correct for the difference 
between peak-to-peak levels reported in Lucke et al. (2009) and rms 
SPLs, the rms SPL for TTS would be approximately 184 dB re: 1 [mu]Pa, 
and the received levels associated with PTS (Level A harassment) would 
be higher. Therefore, based on these studies, NMFS recognizes that TTS 
of harbor porpoises is lower than other cetacean species empirically 
tested (Finneran & Schlundt, 2010; Finneran et al., 2002; Kastelein and 
Jennings, 2012).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so one can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    Masking--In addition, chronic exposure to excessive, though not 
high-intensity, noise could cause masking at particular frequencies for 
marine mammals, which utilize sound for vital biological functions 
(Clark et al., 2009). Acoustic masking is when other noises such as 
from human sources interfere with animal detection of acoustic signals 
such as communication calls, echolocation sounds, and environmental 
sounds important to marine mammals. Therefore, under certain 
circumstances, marine mammals whose acoustical sensors or environment 
are being severely masked could also be impaired from maximizing their 
performance fitness in survival and reproduction.
    Masking occurs at the frequency band that the animals utilize. 
Therefore, since noise generated from vibratory pile driving is mostly 
concentrated at low frequency ranges, it may have less effect on high 
frequency echolocation sounds

[[Page 50738]]

by odontocetes (toothed whales). However, lower frequency man-made 
noises are more likely to affect detection of communication calls and 
other potentially important natural sounds such as surf and prey noise. 
It may also affect communication signals when they occur near the noise 
band and thus reduce the communication space of animals (e.g., Clark et 
al., 2009) and cause increased stress levels (e.g., Foote et al., 2004; 
Holt et al., 2009).
    Unlike TS, masking, which can occur over large temporal and spatial 
scales, can potentially affect the species at population, community, or 
even ecosystem levels, as well as individual levels. Masking affects 
both senders and receivers of the signals and could have long-term 
chronic effects on marine mammal species and populations. Recent 
science suggests that low frequency ambient sound levels have increased 
by as much as 20 dB (more than three times in terms of SPL) in the 
world's ocean from pre-industrial periods, and most of these increases 
are from distant shipping (Hildebrand, 2009). For AGDC's LNG facilities 
construction project, noises from pile driving contribute to the 
elevated ambient noise levels in the project area, thus increasing 
potential for or severity of masking. Baseline ambient noise levels in 
the vicinity of project area are high due to ongoing shipping, 
construction and other activities in Cook Inlet.
    Behavioral Disturbance--Finally, marine mammals' exposure to 
certain sounds could lead to behavioral disturbance (Richardson et al., 
1995), such as changing durations of surfacing and dives, number of 
blows per surfacing, or moving direction and/or speed; reduced/
increased vocal activities; changing/cessation of certain behavioral 
activities (such as socializing or feeding); visible startle response 
or aggressive behavior (such as tail/fluke slapping or jaw clapping); 
avoidance of areas where noise sources are located; and/or flight 
responses (e.g., pinnipeds flushing into water from haulouts or 
rookeries).
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography) and is also difficult to predict (Southall et 
al., 2007). Currently NMFS uses a received level of 160 dB re 1 [mu]Pa 
(rms) to predict the onset of behavioral disturbance from impulse 
noises (such as impact pile driving), and 120 dB re 1 [mu]Pa (rms) for 
continuous noises (such as vibratory pile driving). For the AGDC's LNG 
facilities construction project, both 160- and 120-dB levels are 
considered for effects analysis because AGDC plans to conduct both 
impact and vibratory pile driving.
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification could be biologically significant if the change affects 
growth, survival, and/or reproduction, which depends on the severity, 
duration, and context of the effects.

Potential Effects on Marine Mammal Habitat

    Project activities that could potentially impact marine mammal 
habitats by causing acoustical injury to prey resources and disturbing 
benthic habitat include dredging/trenching, disposal of dredged 
material, and facility installation, as well as impacting marine mammal 
prey from noise generated by in-water pile driving.
    Approximately 42 hectares (103 acres) would be disturbed directly 
by dredging of the Marine Terminal MOF and trenching for the Mainline 
crossing, and another 486 hectares (1,200 acres) would be disturbed by 
the disposal of dredged material. Approximately 26 hectares (64 acres) 
of seafloor would be disturbed by installation of the Marine Terminal 
MOF, Mainline MOF, and Mainline Crossing. Additional area would be 
indirectly affected by the re-deposition of sediments suspended in the 
water column by the dredging/trenching and dredge disposal. However, 
such disturbances are expected to be temporary and mild. Recovery and 
re-colonization of the benthic habitat are expected to occur as soon as 
any anthropogenic stressors are removed.
    With regard to fish as a prey source for cetaceans and pinnipeds, 
fish are known to hear and react to sounds and to use sound to 
communicate (Tavolga et al., 1981) and possibly avoid predators (Wilson 
and Dill, 2002). Experiments have shown that fish can sense both the 
strength and direction of sound (Hawkins, 1981). Primary factors 
determining whether a fish can sense a sound signal, and potentially 
react to it, are the frequency of the signal and the strength of the 
signal in relation to the natural background noise level.
    The level of sound at which a fish will react or alter its behavior 
is usually well above the detection level. Fish have been found to 
react to sounds when the sound level increased to about 20 dB above the 
detection level of 120 dB (Ona, 1988); however, the response threshold 
can depend on the time of year and the fish's physiological condition 
(Engas et al., 1993). In general, fish react more strongly to pulses of 
sound (such as noise from impact pile driving) rather than continuous 
signals (such as noise from vibratory pile driving) (Blaxter et al., 
1981), and a quicker alarm response is elicited when the sound signal 
intensity rises rapidly compared to sound rising more slowly to the 
same level.
    During the Alaska LNG facilities construction, only a small 
fraction of the available habitat would be ensonified at any given 
time. Disturbance to fish species would be short-term, and fish would 
return to their pre-disturbance behavior once the pile driving activity 
ceases. Thus, the proposed construction would have little, if any, 
impact on marine mammals' prey availability in the area where 
construction work is planned.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized through the LOA under the rulemaking, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination. We note several changes that have been made to this 
section since the Proposed Rule was published, including: The density 
of beluga whales used for take estimation has changed; take 
methodologies and estimates for Cook Inlet beluga whale and harbor seal 
have changed for Level B harassment. These changes are described in 
more detail below. In addition, take of fin whale, grey whale, Dall's 
porpoise, California sea lion, and Steller sea lion is no longer 
proposed for authorization because these species are unlikely to occur 
in the AGDC's LNG facilities construction area in Cook Inlet. This is 
explained in the Description of Marine Mammals in the Area of Specified 
Activities section above.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of the MMPA defines ``harassment'' as: Any act of 
pursuit, torment, or annoyance which (i) has the potential to injure a 
marine mammal or marine mammal stock in the wild (Level A harassment); 
or (ii) has the potential to disturb a marine mammal or marine mammal 
stock in the wild by causing disruption of behavioral patterns, 
including, but not limited to, migration, breathing, nursing, breeding, 
feeding, or sheltering (Level B harassment).
    Authorized takes would primarily be by Level B harassment, as noise

[[Page 50739]]

generated from in-water pile driving (vibratory and impact) and anchor 
handling has the potential to result in disruption of behavioral 
patterns for individual marine mammals. There is also some potential 
for auditory injury (Level A harassment) to result, primarily for low- 
and high-frequency cetacean species and phocids because predicted 
auditory injury zones are larger than for mid-frequency cetacean 
species. Auditory injury is unlikely to occur for mid-frequency 
cetacean species. The prescribed mitigation and monitoring measures are 
expected to minimize the severity of such taking to the extent 
practicable.
    As described previously, no serious injury or mortality is 
anticipated or 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 disturbed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to experience 
behavioral disturbance (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of Level B harassment. NMFS predicts that marine mammals are 
likely to experience behavioral disturbance in a manner we consider 
Level B harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g., 
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms) 
for non-explosive impulsive (e.g., seismic airguns) or intermittent 
(e.g., scientific sonar) sources.
    Because AGDC's Alaska LNG facilities project involves the 
generation of non-impulsive (vibratory pile driving and anchor 
handling) and impulsive (impact pile driving) sources, both 120 and 160 
dB re 1 [mu]Pa (rms) thresholds are used to evaluate Level B harassment 
as explained above.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). AGDC's Alaska LNG facilities project 
involves the generation of impulsive (impact pile driving) and non-
impulsive (vibratory pile driving and anchor handling) sources.
    These thresholds are provided in the Table 4 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2016 Technical Guidance, which may be accessed at: 
http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.

                     Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                           PTS onset thresholds                    Behavioral thresholds
          Hearing group          -------------------------------------------------------------------------------
                                       Impulsive         Non-impulsive         Impulsive         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans....  Lpk,flat: 219 dB;   LE,LF,24h: 199 dB.
                                   LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans....  Lpk,flat: 230 dB;   LE,MF,24h: 198 dB.
                                   LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans...  Lpk,flat: 202 dB;   LE,HF,24h: 173 dB.  Lrms,flat: 160 dB.  Lrms,flat: 120 dB.
                                   LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW)             Lpk,flat: 218 dB;   LE,PW,24h: 201 dB.
 (Underwater).                     LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW)            Lpk,flat: 232 dB;   LE,OW,24h: 219 dB.
 (Underwater).                     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 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1 [mu]Pa2s. 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.


[[Page 50740]]

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
Source Levels
    The project includes impact pile driving and vibratory pile driving 
and anchor handling associated with trenching and cable laying 
activities. Source levels of pile driving activities are based on 
reviews of measurements of the same or similar types and dimensions of 
piles available in the literature (Caltrans, 2015). Based on this 
review, the following source levels are assumed for the underwater 
noise produced by construction activities:
     Source levels of impact driving of 18- and 24-inch steel 
piles are based on those of 24-inch steel pile impact driving reported 
by California Department of Transportation (Caltrans) in a pile driving 
source level compendium document (Caltrans, 2015);
     Source level of impact driving of 60-inch steel pile is 
based on that of same type and size of steel pile reported in the 
Caltrans compendium document (Caltrans, 2015) in shallow-water (5 m);
     Source levels of impact driving of 48-inch steel pile is 
based on that of same type and size of steel pile reported by Austin et 
al. (2016) on the Anchorage Port Modernization Project Test Pile 
Program in water depth 18 m;
     Source level of impact pile driving of steel sheet pile is 
based on that of 24-in steel AZ sheet pile impact driving reported in 
the Caltrans compendium (Caltrans, 2015);
     Source levels of vibratory pile driving of 18- and 24-in 
steel piles are based on that of 36-inch steel pile vibratory driving 
reported in the Caltrans compendium (Caltrans, 2015);
     Source levels of vibratory pile driving of 48- and 60-in 
steel piles are based on that of 72-inch steel pile vibratory driving 
reported in the Caltrans compendium (Caltrans, 2015);
     Source level of vibratory pile driving of steel sheet pile 
is based on that of 24-in steel AZ sheet pile vibratory driving 
reported in the Caltrans compendium (Caltrans, 2015); and
     Underwater sound levels associated with offshore pipe 
laying and trenching operations when engaging thrusters and anchor 
handling were based on measurements by Blackwell and Greene (2003) of a 
tug pushing a full barge near the Port of Alaska when engaging 
thrusters during docking. The levels are calculated from measured 149 
dB re 1 [mu]Pa rms at 100 meters/328 feet applying 15*log(r), which 
yield a source level of 178.9 dB re 1 [mu]Pa rms at 1 meter.
    A summary of source levels from different pile driving activities 
is provided in Table 5.

                             Table 5--Summary of In-Water Pile Driving Source Levels
                                              [At 10 m from source]
----------------------------------------------------------------------------------------------------------------
                                               SPLpk (dB re 1   SPLrms (dB re
           Method              Pile type/size    [micro]Pa)     1 [micro]Pa)     SEL (dB re 1       Reference
                                                                                [micro]Pa\2\-s)
----------------------------------------------------------------------------------------------------------------
Impact driving..............  18-in steel                 207             194               178  Caltrans 2015.
                               pipe pile.
Impact driving..............  24-in steel                 207             194               178  Caltrans 2015.
                               pipe pile.
Impact driving..............  48-in steel                 210             200               185  Austin et al.
                               pipe pile.                                                         2016.
Impact driving..............  60-in steel                 210             195               185  Caltrans 2015.
                               pipe pile.
Impact driving..............  Sheet pile.....             205             190               180  Caltrans 2015.
Vibratory driving...........  18-in steel                 180             170               170  Caltrans 2015.
                               pipe pile.
Vibratory driving...........  24-in steel                 180             170               170  Caltrans 2015.
                               pipe pile.
Vibratory driving...........  48-in steel                 183             170               170  Caltrans 2015.
                               pipe pile.
Vibratory driving...........  60-in steel                 183             170               170  Caltrans 2015.
                               pipe pile.
Vibratory driving...........  Sheet pile.....             175             160               160  Caltrans 2015.
Anchor handling and thruster  ...............              NA           178.9             178.9  Blackwell &
                                                                                                  Greene 2003.
----------------------------------------------------------------------------------------------------------------

    These source levels are used to compute the Level A harassment 
zones and to estimate the Level B harassment zones.

Estimating Injury Zones

    When the NMFS' Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of Level A harassment take. However, these tools offer the 
best way to predict appropriate isopleths when more sophisticated 3D 
modeling methods are not available, and NMFS continues to develop ways 
to quantitatively refine these tools, and will qualitatively address 
the output where appropriate. In the prior analysis for the Proposed 
Rule, AGDC used NMFS User Spreadsheet and simple geometric spreading 
model with transmission loss coefficient 15 to calculate Level A and 
Level B harassment distances, respectively. However, after the public 
comment period, in response to NMFS' concern of needing a more 
sophisticated acoustic model to have estimates of the expected 
ensonified zones, AGDC contracted SLR Corporation to perform a 
quantitative noise modeling assessment to identify the ensonified 
distances and areas. Using the dBSea software package, this modeling 
incorporates one-third octave band spectral sound level for each of the 
sources, bathymetry for each project location, water depth, sound speed 
profiles (temperature and salinity for both spring and summer 
profiles), and seafloor characteristics.
    Specifically, pile driving noise was modelled as a single 
stationary, omni-directional point source in each of the three main 
construction areas (PLF, Temporary MOF, and Mainline MOF) for each pile 
and hammer type. Source spectral shape information for each noise 
source and location were used from other studies. All piling sources 
were assumed to be located midway down the water column. Noise 
associated with anchor handling during pipe laying is represented as a 
series of five points on a line along the route, assuming a depth 
midway in the water

[[Page 50741]]

column (see Figure 12 of AGDC LOA application).
    Modelling for this assessment used the dBSea software package. The 
fluid parabolic equation modelling algorithm has been used with 5 
Pad[eacute] terms to calculate the transmission loss between the source 
and the receiver at low frequencies (16 Hz up to 1 kHz). For higher 
frequencies (1 kHz up to 8 kHz) the ray tracing model has been used 
with 1000 reflections for each ray.
    The received noise levels throughout the project have been 
calculated following the procedure outlined below:
     One-third octave source spectral levels are obtained via 
reference spectral curves with subsequent corrections based on their 
corresponding overall source levels;
     Transmission loss is modelled at one-third octave band 
central frequencies along 100 radial paths at regular increments around 
each source location, out to the maximum range of the bathymetry data 
set or until constrained by land;
     The bathymetry variation of the vertical plane along each 
modelling path is obtained via interpolation of the bathymetry dataset 
which has 50 m grid resolution;
     The one-third octave source levels and transmission loss 
are combined to obtain the received levels as a function of range, 
depth and frequency at 100 m intervals; and
     The overall received levels are calculated at a 1-m depth 
resolution along each propagation path by summing all frequency band 
spectral levels.
    The predicted distances to the thresholds and ensonified areas for 
pile driving and anchor handling are summarized in Table 6. In 
practice, the distances to the Level A harassment thresholds are 
controlled by the cumulative sound exposure levels (SELcum) 
within 24 hours.
    For the low frequency cetaceans (humpback whale), the predicted 
distances to the Level A harassment distances range from 238 meters for 
the vibratory driving of sheet piles at the temporary MOF to 3,239 
meters for the impact pile diving of 48-inch pipe piles at the 
temporary MOF. For the mid-frequency cetaceans (beluga and killer 
whales), the predicted distances to the Level SELs range from 0 to 248 
meters for the impact driving of sheet piles at the Mainline MOF. For 
the high frequency cetaceans (harbor porpoise), the predicted distances 
to the Level A harassment distances ranges from 0 to 2,350 meters at 
for impact pile driving of 48-inch and 60-inch pipe piles at the PLF. 
For phocids (harbor seals), the predicted distances to the Level A 
harassment distances ranges from 0 to 1,018 meters impact pile driving 
of 48-inch and 60-inch pipe piles at the PLF.

                             Table 6--Modeled Harassment Zones and Maximum Distances
----------------------------------------------------------------------------------------------------------------
                                            Level A distance (m) (Level A area (km\2\))               Level B
      Activity description       ----------------------------------------------------------------  distance (m)
                                        LF              MF              HF              PW        (area (km\2\))
----------------------------------------------------------------------------------------------------------------
Impact drive of 48-inch pipe      3,175 (10.914)     211 (0.065)   2,350 (8.703)   1,018 (1.984)   3,593 (13.24)
 piles at PLF...................
Impact drive of 60-inch pipe      ..............  ..............  ..............  ..............    2,254 (6.39)
 piles at PLF...................
Vibratory drive of sheet piles       238 (0.039)              NA              NA              NA   4,377 (18.23)
 at temporary MOF...............
Impact drive of 24-inch pipe       1,639 (2.142)     238 (0.018)   1,762 (3.829)     558 (0.477)    2,271 (3.91)
 piles at temporary MOF.........
Impact drive of 48-inch pipe       3,239 (7.442)     238 (0.060)     679 (0.585)     955 (0.935)    3,546 (9.21)
 piles at temporary MOF.........
Vibratory drive of all size pipe     285 (0.125)              NA              NA     246 (0.012)   5,584 (27.70)
 piles at temporary MOF.........
Vibratory drive of sheet piles       244 (0.055)              NA              NA     212 (0.020)   3,179 (14.75)
 at Mainline MOF................
Impact drive of sheet piles at     1,161 (2.365)     248 (0.058)     896 (1.196)     617 (0.696)      764 (1.13)
 Mainline MOF...................
Anchor handling location 1......              NA              NA              NA              NA    1,896 (8.17)
Anchor handling location 2......  ..............  ..............  ..............  ..............   2,855 (20.67)
Anchor handling location 3......  ..............  ..............  ..............  ..............   2,446 (16.50)
Anchor handling location 4......  ..............  ..............  ..............  ..............   2,349 (15.16)
Anchor handling location 5......  ..............  ..............  ..............  ..............    2,195 (5.01)
----------------------------------------------------------------------------------------------------------------
LF: Low-Frequency Cetaceans; MF: Mid-Frequency Cetaceans; HF: High-Frequency Cetaceans; PW: Phocid Pinnipeds,
  Underwater; OW: Otariid Pinnipeds, Underwater.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    Marine mammal density data in the proposed rule were based on NMFS 
aerial survey in Cook Inlet from 2000 to 2016. In the final rule, 
additional density from the 2018 aerial survey were also included.
    In addition, Cook Inlet beluga whale density was further updated 
based on the latest population estimated that became available in 
January 2020 (NMFS, 2020), and take estimate of this species was 
reanalyzed using a more refined density grid than what was used for the 
proposed rule (see below). Take numbers for harbor seals were adjusted 
to account for animals that were hauled out,
    Density estimates were calculated for marine mammals (except beluga 
whales) using aerial survey data collected by NMFS in Cook Inlet 
between 2000 and 2018 (summarized in Shelden et al., 2017; 2019). To 
estimate the densities of marine mammals, the total number of animals 
of each species for each year observed over the 19-year survey period 
was divided by the total area surveyed each year (Tables 7).
    Table 7 summarizes the number of marine mammals, other than beluga 
whales, observed each year during the NMFS Annual Aerial Surveys and 
the area covered. To calculate a conservative density for exposure 
estimation, the total number of individuals per species observed in 
each survey year was divided by the area covered during that year and 
then averaged across all years. The total number of animals observed 
accounts for the entire Cook Inlet, so these densities may not be 
representative of the expected densities at Project locations. The raw 
densities were not corrected for animals missed during the aerial 
surveys as no accurate correction factors are currently available for 
these species except for harbor seal.
    For harbor seal take estimates, density numbers were adjusted using 
a correction factor of 2.33 from Boveng et al. (2012) to revise the 
yearly abundance estimates and resulting density estimates and 
recalculate the number of takes accordingly.

[[Page 50742]]

    The averaged marine mammal densities other than beluga whale is 
provided in Table 8.

                                    Table 7--Sighting and Densities of Marine Mammals Other Than Beluga Whale During NMFS Aerial Survey Between 2000 and 2018
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                     Species                        2000     2001     2002     2003     2004     2005     2006     2007     2008     2009     2010     2011     2012     2014     2016     2018
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale..................................       11       26       20       20       16       18       14        3        7        5        2        9        1       11        6        0
Killer whale....................................        0       15        0        0        0        0        0        0        0        0       33        0        9        0        0        0
Harbor porpoise.................................       29       26        0        0      101        2        0        4        6       42       10       31       11      128       17        0
Harbor seal.....................................    1,800    1,485    1,606      974      956    1,087    1,798    1,474    2,037    1,415    1,156    1,811    1,812    2,115    1,909    1,380
Harbor seal (adjusted)..........................    4,194    3,460    3,742    2,269    2,227    2,533    4,189    3,434    4,746    3,297    2,693    4,220    4,222    4,928    4,448    3,215
Area surveyed (km\2\)...........................    6,911    5,445    5,445    5,236    6,492    5,445    6,702    5,236    7,121    5,864    6,074    6,702    6,283    6,702    8,377   10,471
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           Density estimates (x10-3 individuals/km\2\)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale..................................     1.59     4.78     3.67     3.82     2.46     3.31     2.09     0.57     0.98     0.85     0.33     1.34     0.16     1.64     0.72     0.00
Killer whale....................................     0.00     2.76     0.00     0.00     0.00     0.00     0.00     0.00     0.00     0.00     5.43     0.00     1.43     0.00     0.00     0.00
Harbor porpoise.................................     4.20     4.78     0.00     0.00     15.6     3.67     0.00     0.76     0.84     7.16     1.65     4.63     1.75     19.1     2.03     0.00
Harbor seal.....................................      607      635      687      433      343      465      625      656      667      562      443      630      672      735      531      307
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


 Table 8--Density Estimates for Marine Mammals Other Than Beluga Whales
------------------------------------------------------------------------
                                                           Mean density
                         Species                             (animals/
                                                              km\2\)
------------------------------------------------------------------------
Humpback whale..........................................         0.00177
Killer whale............................................         0.00060
Harbor porpoise.........................................         0.00439
Harbor seal.............................................         0.56246
------------------------------------------------------------------------

    Beluga whale density estimates were based on the maximum number of 
beluga whales observed during each survey year of the NMFS Annual 
Aerial Surveys and the area covered. To estimate beluga densities, the 
maximum number of belugas observed each survey year was divided by the 
area covered, and these annual densities were then averaged across all 
16 survey years. The survey area can be separated into Upper, Middle, 
and Lower Cook Inlet, resulting in different densities for beluga 
whales in each area. Using these combined data for Middle and Lower 
Cook Inlet, the density for beluga whales using the NMFS Annual Aerial 
Surveys for all Project components is 0.00050 whales per square 
kilometer, which is what was used for take estimation in the Proposed 
Rule.
    Goetz et al. (2012) modeled aerial survey data collected by NMFS 
between 1993 and 2008 and developed beluga whale summer densities for 
each 1-square-kilometer (0.4-square-mile) cell of Cook Inlet. Given the 
clumped and distinct distribution of beluga whales in Cook Inlet during 
the summer months, these results provide a more precise estimate of 
beluga whale density at a given location than multiplying all aerial 
observations by the total survey effort. Accordingly, NMFS used more 
refined density estimates to inform the take calculations in this Final 
Rule. To develop a density estimate associated with Project components, 
the GIS files of the predicted ensonified area for both Level A and B 
associated with each location and pile type, size, and hammer were 
overlain with the GIS file of the 1-square-kilometer (0.4-square-mile) 
beluga density cells. The cells falling within each ensonified area 
were provided in an output spreadsheet, and an average cell density for 
each Project component was calculated. Table 9 shows beluga density for 
each project component.

 Table 9--Average Beluga Whale Density (Animals/km\2\) Within Predicted
     Level A and Level B Harassment Areas for Each Project Component
------------------------------------------------------------------------
                                       Average density   Average density
          Project component            within Level A    within Level B
                                       harassment zone   harassment zone
------------------------------------------------------------------------
Impact drive for 48-inch pipe piles            0.00004           0.00005
 at PLF.............................
Impact drive for 60-inch pipe piles            0.00005           0.00005
 at PLF.............................
Impact drive for 24-inch pipe piles            0.00000           0.00005
 at temporary MOF...................
Impact drive for 48-inch pipe piles            0.00000           0.00005
 at temporary MOF...................
Vibratory drive for all size pipe              0.00000           0.00005
 piles at temporary MOF.............
Vibratory drive for sheet piles at             0.00000           0.00006
 temporary MOF......................
Impact drive for sheet piles at                0.04150           0.04146
 Mainline MOF.......................
Vibratory drive for sheet piles at             0.00000           0.03245
 Mainline MOF.......................
Anchor handling at Location 1.......           0.00000           0.02199
Anchor handling at Location 2.......           0.00000           0.00180
Anchor handling at Location 3.......           0.00000           0.00075
Anchor handling at Location 4.......           0.00000           0.00284
Anchor handling at Location 5.......           0.00000           0.02323
Anchor handling at all locations....           0.00000           0.00551
------------------------------------------------------------------------

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate. For all marine 
mammals, estimated takes are calculated based on ensonified area for a 
specific pile driving activity multiplied by the marine mammal density 
in the action area, multiplied by the number of pile driving days.
    For both Level A and Level B harassment, estimated exposure are 
calculated using the following steps:
     Number of takes per activity = density (average number of 
animals per km\2\) * area of ZOI (km\2\) * number of days;
     Marine mammal densities in the project area are provided 
in Tables 8 and 9;

[[Page 50743]]

     The number of days for each activity component is provided 
in Table 1; and
     Takes by Level A and Level B harassment are calculated 
separately based on the respective ZOIs for each type of activity, 
providing a maximum estimate for each type of take which corresponds to 
the authorization requested under the MMPA.
    For beluga whale, NMFS considered group size from the long-term 
scientific monitoring effort and opportunistic observation data at Port 
of Alaska to determine if these numbers represented realistic 
scenarios. The Alaska Pacific University (APU) scientific monitoring 
data set documented 390 beluga whale sightings. Group size exhibits a 
mode of 1 and a median of 2, indicating that over half of the beluga 
groups observed over the 5-year span of the monitoring program were of 
individual beluga whales or pairs. The 95th percentile of group size 
from the APU scientific monitoring data set is 11.1 beluga whales. This 
means that, of the 390 documented beluga whale groups in this data set, 
95 percent consisted of fewer than 11.1 whales; 5 percent of the groups 
consisted of more than 11.1 whales. Therefore, a group number of 11 is 
added to the estimated value to allow for one encounter with a larger 
group of whales.
    For killer whale and harbor porpoise, a group number of 3 is added 
to the estimated value to adjust for estimated takes of these two 
species.
    The estimated numbers of instances of acoustic harassment (takes) 
by year, species and severity (Level A or Level B) are shown in Table 
10.

          Table 10--Estimated Numbers of Marine Mammals That May Be Exposed to Received Noise Levels That Cause Level A and Level B Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                            Percentage
                                                                             Estimated       Estimated       Estimated                      (instances
                   Year                                Species                Level A         Level B       total take       Abundance      take versus
                                                                            harassment      harassment                                      abundance)
--------------------------------------------------------------------------------------------------------------------------------------------------------
1.........................................  Humpback whale *............               0               1               1           1,107            0.09
                                            Killer whale................               0               4               4           2,347            0.17
                                            Beluga whale................               0              11              11             279            3.94
                                            Harbor porpoise.............               0               5               5          31,046            0.02
                                            Harbor seal.................               1             316             317          28,411            1.12
2.........................................  Humpback whale *............               0               4               4           1,107            0.36
                                            Killer whale................               0               4               4           2,347            0.17
                                            Beluga whale................               0              14              14             279            5.02
                                            Harbor porpoise.............               0              12              12          31,046            0.04
                                            Harbor seal.................               4           1,080           1,084          28,411            3.82
3.........................................  Humpback whale *............               1               2               3           1,107            0.27
                                            Killer whale................               0               4               4           2,347            0.04
                                            Beluga whale................               0              12              12             279            4.30
                                            Harbor porpoise.............               4               5               9          31,046            0.03
                                            Harbor seal.................              21             169             190          28,411            0.67
4.........................................  Humpback whale *............               1               2               3           1,107            0.27
                                            Killer whale................               0               5               5           2,347            0.21
                                            Beluga whale................               0              13              13             279            4.66
                                            Harbor porpoise.............               4               6              10          31,046            0.03
                                            Harbor seal.................              17             236             253          28,411            0.89
5.........................................  Humpback whale *............               1               1               2           1,107            0.18
                                            Killer whale................               0               4               4           2,347            0.17
                                            Beluga whale................               0              11              11             279            3.94
                                            Harbor porpoise.............               5               5              10          31,046            0.03
                                            Harbor seal.................              45             190             235          28,411            0.83
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Includes Hawaii, Western North Pacific, and Mexico DPS's.

Mitigation

    In order to issue an LOA under Section 101(a)(5)(A) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such species or stock for taking for certain 
subsistence uses (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 such 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned) the likelihood of effective implementation (probability 
implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.

[[Page 50744]]

    Additional mitigation measures that were not included in the 
proposed rule but were added to the final rule include:
    (1) Time/area restriction of pile driving and noise generating 
activities during summer months in the western portion of Cook Inlet at 
the Mainline Material Offloading Facility (Mainline MOF). The density 
of beluga whales is notably higher in this area and the measure was 
added in order to further reduce the number of takes of beluga whales.
    (2) Deployment of air bubble curtains for in-water pile driving 
activities if the air bubble curtains can show to reduce noise level by 
2 dB. This measure is to reduce the noise level from pile driving, as 
air bubble curtain system would reduce potential takes of marine 
mammals by reducing the ensonified zones. The in situ measurement will 
determine whether continued implementation is warrant by measuring the 
likely conservation benefit (degree of sound reduction) versus the 
financial cost to the company.
    (3) Vessel speed and transits restriction in western portion of 
Cook Inlet during summer months. This measure would minimize 
disturbances to beluga whales in the Susitna Delta during the time when 
beluga whales are likely to congregate in the area.
    NMFS included these mitigation measures after working with AGDC and 
determined that they are practicable to further reduce potential 
impacts to Cook Inlet beluga whales.

Time/Area Restriction

    For pile driving, work would occur only during daylight hours, when 
visual monitoring of marine mammals can be conducted. Other 
construction activities, such as pipe laying, anchor handling, and 
dredging could occur outside of daylight hours or during periods of low 
visibility.
    Pile driving associated with the Mainline MOF will not occur from 
June 1 to September 7 (pile driving can occur from September 8 to May 
31).
    Other than the activities described in the Description of Proposed 
Activity section (e.g., sheet pile driving, anchor handling, trenching, 
pipe-laying and support vessels), AGDC will not engage in in-water 
sound-producing activities within 10 miles (16 km) of the mean higher 
high water (MHHW) line of the Susitna Delta (Beluga River to the Little 
Susitna River) between April 15 and October 15 for activities with 
underwater noise levels in excess of 120 dB rms re 1[micro]Pa @1 m.

Establishing and Monitoring Level A and Level B Harassment Zones, and 
Exclusion Zones

    Before the commencement of in-water construction activities, which 
include impact pile driving and vibratory pile driving, AGDC must 
establish Level A harassment zones where received underwater 
SELcum could cause PTS (see Table 6 above).
    AGDC must also establish Level B harassment zones where received 
underwater SPLs are higher than 160 dBrms re 1 [micro]Pa for 
impulsive noise sources (impact pile driving) and 120 dBrms 
re 1 [micro]Pa for non-impulsive noise sources (vibratory pile 
driving).
    For all impact and vibratory pile driving, AGDC is required to 
establish the exclusion zones and implement shutdown measures for 
humpback whale and killer whale to prevent Level A harassment. AGDC is 
required to establish a maximum of 1,000-m exclusion zone and implement 
shutdown measures for harbor porpoise and harbor seal to minimize Level 
A harassment. AGDC is required to establish the exclusion zones and 
implement shutdown measures for beluga whale to prevent Level A and 
Level B harassment. AGDC is required to establish a 2,900-m clearance 
zone for beluga whale before activities involving anchor handling can 
occur.
    If visibility degrades to where the entire exclusion zones cannot 
be effectively monitored during pile driving, AGDC may continue to 
drive the pile section that was being driven to its target depth but 
will not drive additional sections of pile.
    Further, AGDC must implement shutdown measures if the number of 
marine mammals observed within harassment zones and recorded as a takes 
for any particular marine mammal species reaches the authorized limit, 
or any marine mammal species/stocks not authorized to take under the 
LOA, and such species are sighted within the vicinity of the project 
area and are approaching the Level B harassment zone during in-water 
construction activities.
    A summary of these exclusion zones based on Level A and Level B 
harassment distances for different project components is provided in 
Table 11.

                                     Table 11--Marine Mammal Exclusion Zones
----------------------------------------------------------------------------------------------------------------
                                                              Exclusion distances (m)
                                 -------------------------------------------------------------------------------
     Pile driving activities                                          Harbor
                                  Humpback whale   Killer whale      porpoise       Harbor seal   Beluga whale *
----------------------------------------------------------------------------------------------------------------
Impact pile driving of 48- and             3,200             250           1,000           1,000           3,600
 60-inch piles at PLF...........
Impact pile driving of 24- and             3,300             250           1,000           1,000           3,600
 48-inch piles at temporary MOF.
Vibratory pile driving of all                300             250             250             250           5,600
 types and sizes of piles at
 temporary MOF..................
Vibratory pile driving of sheet              300             250             250             250           3,200
 piles at Mainline MOF..........
Impact pile driving of sheet               1,200             250           1,000             650             800
 piles at Mainline MOF..........
Anchor handling.................              NA              NA              NA              NA        ** 2,900
----------------------------------------------------------------------------------------------------------------
* These zones also apply to all marine mammals if the number of take is approaching to the authorized takes, and
  to all marine mammals that takes are not authorized.
** The 2,900m zone will be a clearing zone prior to the start of work, since activities cannot start and stop.
  Beluga whales occurring within this clearing zone during anchor handling operations will be recorded as having
  been taken by harassment.

    In all cases, a minimum of 10-m exclusion zone must be established 
for in-water construction and heavy machinery not addressed elsewhere 
in these measures. If marine mammals are found within the exclusion 
zone, pile driving of the segment would be delayed until they move out 
of the area. If a marine mammal is seen above water and then dives 
below, the contractor would wait 30 minutes for large cetaceans (baleen 
whales) and 15 minutes for small cetaceans (beluga and killer whales 
and porpoises) and pinnipeds. If no marine mammals of that species are 
seen by the observer in that time it can be assumed that the

[[Page 50745]]

animal has moved beyond the exclusion zone.
    If pile driving of a segment ceases for 30 minutes or more and a 
marine mammal is sighted within the designated exclusion zone prior to 
commencement of pile driving, the observer(s) must notify the pile 
driving operator (or other authorized individual) immediately and 
continue to monitor the exclusion zone. Operations may not resume until 
the marine mammal has exited the exclusion zone or 30 minutes have 
elapsed for large cetaceans or 15 minutes have elapsed for small 
cetaceans and pinnipeds since the last sighting.

Soft Start

    Once the exclusion zone has been cleared of all marine mammals, 
soft-start procedures must be implemented immediately prior to impact 
pile driving activities. Soft-start is comprised of an initial set of 
three strikes from the hammer at about 40 percent energy, followed by a 
30-seconds waiting period, then two subsequent three-strike sets with 
associated 30-seconds waiting periods at the reduced energy.
    If circumstances result in discontinuation of pile driving for 
greater than 30 minutes, then the PSO will monitor the exclusion zone 
for 30 minutes prior to the resumption of pile driving and will ensure 
that the zone remains devoid of marine mammals for the 30 minutes 
immediately prior to the restarting of pile driving. Impact Pile 
driving will resume following an additional soft start.

Noise Attenuation

    For pile-driving at the Mainline MOF near the Beluga River, and on 
the east side of Cook Inlet near Nikiski associated with the 
liquefaction facility, AGDC must deploy air bubble curtains around 
piles. If the sound source verification (SSV) measurements indicate 
that the best-performing bubble curtain configuration provides less 
than a 2 dB reduction in in-water sound beyond the bubble curtain, use 
of the bubble curtain may be discontinued.

Vessel Transits

    Consistent with NMFS marine mammal viewing guidelines (https://alaskafisheries.noaa.gov/pr/mm-viewing-guide), operators of vessels 
will, at all times, avoid approaching within 100 yards of marine 
mammals. Operators will observe direction of travel of marine mammals 
and attempt to maintain a distance of 100 yards or greater between the 
animal and the vessel by working to alter vessel course or velocity.
    The vessel operator will avoid placing the vessel between members 
of a group of marine mammals in a way that may cause separation of 
individuals in the group from other individuals in that group. A group 
is defined as being three or more whales observed within 500-m (1,641-
ft) of one-another and displaying behaviors of directed or coordinated 
activity (e.g., migration or group feeding).
    If the vessel approaches within 1.6 km (1 mi) of one or more 
whales, the vessel operator will take reasonable precautions to avoid 
potential interaction with the whales by taking one or more of the 
following actions, as appropriate:
    (1) Steering to the rear of whale(s) to avoid causing changes in 
their direction of travel.
    (2) Maintaining vessel speed of 10 knots (19 km/hr) or less when 
transiting to minimize the likelihood of lethal vessel strikes.
    (3) Reducing vessel speed to less than 5 knots (9 km/hour) within 
274 m (300 yards) of the whale(s).
    Project vessels must remain a minimum of 2.8 km (1.5 nm) seaward of 
the mean lower low water (MLLW) line between the Little Susitna River 
and -150.80 degrees west longitude (see Figure 2 for line depicting the 
approximate MLLW line) to minimize the impacts of vessel sound and 
avoid strikes on Cook Inlet beluga whales within this highly essential 
portion of their critical habitat during late spring and throughout the 
summer the Susitna Delta Exclusion Zone is defined as the union of the 
areas defined by:
    (1) A 16 km (10-mile) buffer of the Beluga River thalweg seaward of 
the mean lower low water (MLLW) line,
    (2) A 16 km (10-mile) buffer of the Little Susitna River thalweg 
seaward of the MLLW line, and,
    (3) A 16 km (10-mile) seaward buffer of the MLLW line between the 
Beluga River and Little Susitna River.
    (4) The buffer extends landward along the thalweg to include 
intertidal waters within rivers and streams up to their mean higher 
high water line (MHHW). The seaward boundary has been simplified so 
that it is defined by lines connecting readily discernable landmarks.
    For vessels operating in the Susitna Delta Exclusion Zone, the 
following will be implemented:
    (1) All project vessels operating within the designated Susitna 
Delta area will maintain a speed above ground below 4 knots. PSOs will 
note the numbers, date, time, coordinates, and proximity to vessels of 
all belugas observed during operations, and report these observations 
to NMFS in monthly PSO reports.
    (2) Vessel crew will be trained to monitor for ESA-listed species 
prior to and during all vessel movements within the Susitna Delta 
Exclusion Zone. The vessel crew will report sightings to the PSO team 
for inclusion in the overall sighting database and reports.
    (3) Vessel operators will not move their vessels when they are 
unable to adequately observe the 100-meter zone around vessels under 
power (in gear) due to darkness, fog, or other conditions, unless 
necessary for ensuring human safety.

[[Page 50746]]

[GRAPHIC] [TIFF OMITTED] TR17AU20.448

    Based on our evaluation of the required measures, NMFS has 
determined that the prescribed mitigation measures provide the means 
effecting the least practicable adverse impact on the affected species 
or stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Monitoring and Reporting

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

Visual Monitoring

    Marine mammal monitoring must be conducted in accordance with the 
Marine Mammal Monitoring Plan, dated April 2020. Marine mammal 
monitoring during pile driving and removal must be conducted by NMFS-
approved PSOs in a manner consistent with the following:
     Independent PSOs (i.e., not construction personnel) who 
have no other assigned tasks during monitoring periods must be used;
     Where a team of three or more PSOs are required, a lead 
observer or monitoring coordinator must be designated. The lead 
observer must have prior experience working as a marine mammal observer 
during construction;
     Other PSOs may substitute education (degree in biological 
science or related field) or training for experience. PSOs may also 
substitute

[[Page 50747]]

Alaska native traditional knowledge for experience. (NMFS recognizes 
that PSOs with traditional knowledge may also have prior experience and 
be eligible to serve as the lead PSO.); and
     AGDC must submit PSO CVs for approval by NMFS prior to the 
onset of pile driving.
    PSOs must have the following additional qualifications:
     Ability to conduct field observations and collect data 
according to assigned protocols;
     Experience or training in the field identification of 
marine mammals, including the identification of behaviors;
     Sufficient training, orientation, or experience with the 
construction operation to provide for personal safety during 
observations;
     Writing skills sufficient to prepare a report of 
observations including but not limited to the number and species of 
marine mammals observed; dates and times when in-water construction 
activities were conducted; dates, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
and marine mammal behavior; and
     Ability to communicate orally, by radio or in person, with 
project personnel to provide real-time information on marine mammals 
observed in the area as necessary.
    Marine mammal monitoring must comply with the follow protocols:
    (1) For pile driving activities, a minimum of two PSOs must be on 
duty at all times;
    (2) For pile driving activities, PSOs must be stationed on a bluff 
with minimum height at 500 feet above sea level immediately above the 
construction site;
    (3) For marine mammal monitoring during pipe laying activities, at 
least one PSO must be on the barge and on watch;
    (4) PSOs may not exceed 4 consecutive watch hours; must have a 
minimum two-hour break between watches; and may not exceed a combined 
watch schedule of more than 12 hours in a 24-hour period;
    (5) PSOs must have no other construction-related tasks while 
conducting monitoring;
    (6) Monitoring must be conducted from 30 minutes prior to 
commencement of pile driving, throughout the time required to drive a 
pile, and for 30 minutes following the conclusion of pile driving;
    (7) Monitoring must be conducted from 30 minutes prior to 
commencement of pipe laying activity, throughout the time of pipe 
laying, and for 30 minutes following the conclusion of pipe laying for 
the segment;
    (8) During all observation periods, PSOs must use high-
magnification (25X), as well as standard handheld (7X) binoculars, and 
the naked eye to search continuously for marine mammals;
    (9) Monitoring distances must be measured with range finders. 
Distances to animals must be based on the best estimate of the PSO, 
relative to known distances to objects in the vicinity of the PSO; and
    (10) Bearings to animals must be determined using a compass.
    PSOs must collect the following information during marine mammal 
monitoring:
    (1) Date and time that monitored activity begins and ends for each 
day conducted (monitoring period);
    (2) Construction activities occurring during each daily observation 
period, including how many and what type of piles driven and distances 
covered during pipe laying;
    (3) Deviation from initial proposal in pile numbers, pile types, 
average driving times, and pipe laying distances, etc.;
    (4) Weather parameters in each monitoring period (e.g., wind speed, 
percent cloud cover, visibility);
    (5) Water conditions in each monitoring period (e.g., sea state, 
tide state);
    (6) For each marine mammal sighting:
    [cir] Species, numbers, and, if possible, sex and age class of 
marine mammals;
    [cir] Description of any observable marine mammal behavior 
patterns, including bearing and direction of travel and distance from 
pile driving and pipe laying activities, and notable changes in 
patterns;
    [cir] Location and distance from pile driving and pipe laying 
activities to marine mammals and distance from the marine mammals to 
the observation point; and
    [cir] Estimated amount of time that the animals remained in the 
Level A and/or Level B harassment zones;
    (7) Description of implementation of mitigation measures within 
each monitoring period (e.g., shutdown or delay); and
    (8) Other human activity in the area within each monitoring period.

Acoustic Monitoring

    AGDC must conduct sound source verification (SSV) in accordance 
with the Sound Source Verification Plan, dated February 12, 2020, at 
the beginning of the pile driving to characterize the sound levels 
associated with different pile and hammer types, as well as to 
establish the marine mammal monitoring and mitigation zones.
    (1) A minimum of 2 piles of each type and size must be measured.
    (2) The following data, at minimum, shall be collected during 
acoustic monitoring and reported:
    i. Hydrophone equipment and methods: Recording device, sampling 
rate, distance from the pile where recordings were made; depth of 
recording device(s).
    ii. Type of pile being driven and method of driving during 
recordings.
    iii. Mean, median, and maximum sound levels (dB re: 1[micro]Pa): 
Cumulative sound exposure level (SELcum), peak sound 
pressure level (SPLpeak), root mean square sound pressure 
level (SPLrms), and single-strike sound exposure level 
(SELs-s).
    (3) An SSV report must be submitted to NMFS within 72 hours after 
field measurements for approval of the results.
    (4) The results of the SSV report may be used to adjust the extent 
of Level A and Level B harassment zones in-water pile driving.

Reporting

    AGDC must notify NMFS 48 hours prior to the start of each activity 
in Cook Inlet that may cause harassment of marine mammals. If there is 
a delay in activity, AGDC will also notify NMFS as soon as practicable.
    AGDC must submit monthly reports via email to NMFS Office of 
Protected Resources (OPR) and Alaska Regional Office (AKRO) for all 
months with project activities by the 15th of the month following the 
monthly reporting period. For example, for the monthly reporting period 
of June 1-30, the monthly report will be submitted by July 15. The 
monthly report will contain and summarize the following information:
     Dates, times, locations, heading, speed, weather, sea 
conditions (including Beaufort sea state and wind force), and a list of 
all in-water sound-producing activities occurring concurrent with 
marine mammal observations.
     Species, number, location, distance from the vessel, and 
behavior of all observed marine mammals, as well as associated project 
activity (e.g., number of power-downs and shutdowns), observed 
throughout all monitoring activities.
     Observation data in (a) and (b) above will be provided in 
digital spreadsheet format that can be queried.
     An estimate of the number of animals (by species) exposed 
to sound at received levels greater than or equal to either the Level A 
or Level B harassment thresholds, with a

[[Page 50748]]

discussion of any specific behaviors those individuals exhibited.
     If the extent of Level B harassment zone is beyond visual 
observation, AGDC should make appropriate adjustment to estimate the 
numbers of marine mammals taken based on the portion of the areas that 
are monitored.
     A description of the implementation and effectiveness of 
the: (i) Terms and conditions of the Biological Opinion's Incidental 
Take Statement; and (ii) mitigation measures of the LOA. For the 
Biological Opinion, the report will confirm the implementation of each 
Term and Condition, as well as any conservation recommendations, and 
describe their effectiveness for minimizing the adverse effects of the 
action on ESA-listed marine mammals.
    In addition, AGDC is required to keep a tally of the estimated 
number of marine mammals taken, and alert NMFS when the authorized 
limit is close to being met based on prescribed monitoring measured in 
the final rule. In addition, AGDC is required to keep a tally of all 
marine mammal sightings during the pile driving activities.
    AGDC should immediately notify NMFS if the number of Cook Inlet 
beluga takes documented reaches 80% of the authorized takes in any 
given calendar year during which take is authorized.
    Within 90 calendar days of the cessation of in-water work each 
year, a comprehensive annual report will be submitted to NMFS for 
review. The report will synthesize all sighting data and effort during 
each activity for each year. NMFS will provide comments within 30 days 
after receiving annual reports, and the action agency or its non-
federal designee will address the comments and submit revisions within 
30 days after receiving NMFS comments. If no comments are received from 
the NMFS within 30 days, the annual report is considered completed. The 
report will include the following information:
     Summaries of monitoring effort including total hours, 
observation rate by species and marine mammal distribution through the 
study period, accounting for sea state and other factors affecting 
visibility and detectability of marine mammals.
     Analyses of the effects of various factors that may have 
influenced detectability of marine mammals (e.g., sea state, number of 
observers, fog/glare, and other factors as determined by the PSOs).
     Species composition, occurrence, and distribution of 
marine mammal sightings, including date, water depth, numbers, age/
size/gender categories (if determinable), group sizes, and ice cover.
     Marine mammal observation data with a digital record of 
observation data provided in digital spreadsheet format that can be 
queried.
     Summary of implemented mitigation measures (i.e., 
shutdowns and delays).
     Number of marine mammals during periods with and without 
project activities (and other variables that could affect 
detectability), such as: (i) Initial sighting distances versus project 
activity at the time of sighting; (ii) closest point of approach versus 
project activity; (iii) observed behaviors and types of movements 
versus project activity; (iv) numbers of sightings/individuals seen 
versus project activity; (v) distribution around the source vessels 
versus project activity; and (vi) numbers of animals detected in the 
exclusion zone.
     Analyses of the effects of project activities on listed 
marine mammals.
    In addition to providing NMFS monthly and annual reporting of 
marine mammal observations and other parameters described above, AGDC 
will provide NMFS, within 90 days of project completion at the end of 
the five-year period, a report of all parameters listed in the monthly 
and annual report requirements above, noting also all operational 
shutdowns or delays necessitated due to the proximity of marine 
mammals. NMFS will provide comments within 30 days after receiving this 
report, and the action agency or its non-federal designee will address 
the comments and submit revisions within 30 days after receiving NMFS 
comments. If no comments are received from the NMFS within 30 days, the 
final report is considered as final.
    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, AGDC must immediately cease 
the specified activities and report the incident to the Office of 
Protected Resources (OPR) (301-427-8401), NMFS and to the Alaska 
regional stranding coordinator (907-586-7209) as soon as feasible. If 
the death or injury was clearly caused by the specified activity, AGDC 
must immediately cease the specified activities until NMFS is able to 
review the circumstances of the incident and determine what, if any, 
additional measures are appropriate to ensure compliance with the terms 
of the LOA. AGDC must not resume their activities until notified by 
NMFS.
    The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.

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 the species listed in Table 3, given that the 
anticipated effects of AGDC's Alaska LNG facilities construction 
project activities involving pile driving and pipe laying on marine 
mammals are expected to be relatively similar in nature. Among the 
species that would be affected from AGDC's LNG facilities construction 
activities, the Cook Inlet beluga whale is expected to be the most 
vulnerable species due to its small

[[Page 50749]]

population and declining status (NMFS, 2020), and additional species-
specific information is included in the analysis below.
    Pile driving and removal activities associated with the project as 
well as pipe laying activity, 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 B 
harassment, from underwater sounds generated from pile driving and pipe 
laying. Potential takes could occur if individuals of these species are 
present in zones ensonified above the thresholds for Level A or Level B 
harassment, identified above, when these activities are underway.
    Cook Inlet beluga whale and humpback whales are listed as 
endangered under the ESA. These stocks are also considered depleted 
under the MMPA. The estimated annual rate of decline for Cook Inlet 
beluga whales was 0.6 percent between 2002 and 2012. Data from 
Calambokidis et al. (2008) suggest the population of humpback whales 
may be increasing. The other species that may be taken by harassment 
during AGDC's LNG facilities construction project are not listed as 
threatened or endangered under the ESA nor as depleted under the MMPA.
    Although a few individual marine mammals (up to 3 humpback whales, 
13 harbor porpoises, and 88 harbor seals over the entire project 
duration of 5 years) are estimated to experience Level A harassment in 
the form of PTS if they stay within the Level A harassment zone during 
the entire pile driving for the day, the degree of injury that might 
occur would be expected to be mild and not likely to affect the 
reproduction or survival of the individual animals. Specifically, it is 
expected that, if hearing impairments occur, most likely the affected 
animal would lose a few dB in its hearing sensitivity, limited to the 
dominant frequency of the noise sources, i.e., in the low-frequency 
region below 2 kHz. While we have considered the potential impacts to 
any individuals that could incur PTS, and the number authorized, we 
reiterate that in general marine mammals are likely to avoid areas 
where sound levels are intense enough to cause hearing impairment and 
it is unlikely to occur.
    Under the majority of the circumstances, anticipated takes are 
expected to be limited to relatively short-term Level B harassment. 
Marine mammals present in the vicinity of the action area during the 
construction season and taken by Level B harassment would most likely 
show overt brief disturbance (startle reaction) and avoidance of the 
area from elevated noise levels during pile driving. Given the limited 
estimated number of incidents of Level A and Level B harassment and the 
limited, anticipated short-term nature of the responses by the 
individuals, the impacts of the estimated take are not expected to 
impact the fitness, reproduction, or survival of any individual marine 
mammals, and further are not expected to rise to the level that they 
would adversely affect any marine mammal species at the population 
level, through effects on annual rates of recruitment or survival. 
While AGDC's LNG facilities construction activities could in general 
increase the ambient noise level in the vicinity of the project area, 
the elevated noise levels are only expected during the construction 
work window during daytime and in the limited area immediately around 
the construction activities. Additionally, any potential auditory 
masking occur primarily in the frequency band of the noise, which is 
generally below 2 kHz for in-water pile driving, and would not be 
expected to mask most communication vocalizations of the species in the 
area, or echolocation calls. Given this, any potential auditory masking 
for marine mammals in the project area is expected to have relatively 
minor impacts.
    Mitigation measures such as time/area restrictions, dedicated 
marine mammal observers, pre-construction exclusion zone clearance, 
deployment of air bubble curtains, soft-start, and shutdown measures 
when marine mammals are seen within the exclusion zones reduce both the 
number and severity of behavioral disturbances and minimize any effects 
on hearing sensitivity. In most cases, only cause Level B harassment in 
the form of behavioral disturbance and/or temporary avoidance. While 
some Level A harassment to a few individual harbor seals, harbor 
porpoises, and humpback whales may occur, individuals are unlikely to 
remain in the proximity of the source for a duration of time likely to 
result in more than a few dB of PTS (low level), and therefore these 
impacts are unlikely to impact individual fitness, reproduction, or 
survival incurred would be expected to be of a low level (no more than 
a few dB).
    The area where the activities will take place is within the Cook 
Inlet beluga whale critical habitat. Satellite-tagging studies and 
aerial survey indicate that seasonal shifts exist in Cook Inlet beluga 
whale distribution, with the whales spending a great percentage of time 
in coastal areas during the summer and early fall (June through October 
or November), and dispersing to larger ranges that extend to the middle 
of the inlet in winter and spring (November or December through May) 
(Hansen and Hubbard, 1999; Rugh et al., 2004; Hobbs et al., 2005; Goetz 
et al., 2012). However, fine scale modeling based on NMFS long-term 
aerial survey data indicate that the AGDC's proposed LNG facilities 
construction does not overlap with beluga whale high density areas 
during the summer and fall (Goetz et al., 2012). Furthermore, specific 
mitigation measures are required to offer additional protections to 
Cook Inlet beluga whales given the vulnerable status of the population. 
These measures call for time and area restriction for all activities 
that generate underwater noise greater than 120 dB rms re 1 [micro]Pa, 
including in-water pile driving events, in west Cook Inlet construction 
area during summer months when beluga whales are likely to use the 
Susitna River delta for feeding. Additional mitigation measure to 
protect the Cook Inlet beluga whale also include implementing shutdown 
measures for beluga whales to prevent Level B harassment. These 
measures are expected reduce both the number and severity of the takes 
of beluga whales.
    There are no known important habitats, such as rookeries or 
haulouts, in the vicinity of the AGDC's LNG facilities construction 
project for other marine mammal species. The project also is not 
expected to have significant adverse effects on affected marine 
mammals' habitat, including prey, as analyzed in detail in the 
Anticipated Effects on Marine Mammal Habitat section. Therefore, the 
exposure of marine mammals to sounds produced by AGDC's LNG facilities 
construction activities is not anticipated to have an effect on annual 
rates of recruitment or survival of the affected species or stocks.
    In summary and as described above, the following factors primarily 
support our determination that the impacts resulting from this activity 
are not expected to adversely affect the species or stock through 
effects on annual rates of recruitment or survival:
     No series injury or mortality is anticipated or 
authorized;
     Injury--a small individuals of humpback whales, harbor 
porpoises, and harbor seals could experience mild level of PTS as a 
form of injury. However, as mentioned earlier in this section, the 
level of PTS is expected to be small;
     TTS--a small individuals of marine mammals could 
experience mild level of TTS before the threshold shifts become 
permanent. However, most of the TTS effects are expected to be brief

[[Page 50750]]

in duration, and will not progress into PTS;
     Behavioral disturbance--most of the noise effects on 
marine mammals are expected to be in the form of behavioral 
disturbance. However, such effects are expected to be in short 
duration, within the day during the construction activities when the 
animal is nearby. As construction activities only occur for a maximum 
of 12 hours during daylight hours between April and October of the 
year, chronic noise exposure would be limited; and
     Important Areas--the area where the activities will take 
place is within the Cook Inlet beluga whale critical habitat. However, 
fine scale modeling based on NMFS long-term aerial survey data indicate 
that the AGDC's proposed LNG facilities construction does not overlap 
with beluga whale high density areas during the summer and fall.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the monitoring and mitigation 
measures, NMFS finds that the total marine mammal take from the 
proposed activity will have a negligible impact on all affected marine 
mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under section 101(a)(5)(A) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers and so, in practice, NMFS compares the number of 
individuals taken to the most appropriate estimation of abundance of 
the relevant species or stock in our determination of whether an 
authorization is limited to small numbers of marine mammals.
    The number of authorized takes are below one third of the stock 
abundance (in fact less than seven percent) of the population for all 
marine mammals (Table 10).
    Based on the analysis contained herein of the proposed activity 
(including the prescribed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS finds that small numbers of 
marine mammals will be taken relative to the population size of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue an LOA, NMFS must find that the specified 
activity will not have an ``unmitigable adverse impact'' on the 
subsistence uses of the affected marine mammal species or stocks by 
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50 
CFR 216.103 as an impact resulting from the specified activity: (1) 
That is likely to reduce the availability of the species to a level 
insufficient for a harvest to meet subsistence needs by: (i) Causing 
the marine mammals to abandon or avoid hunting areas; (ii) Directly 
displacing subsistence users; or (iii) Placing physical barriers 
between the marine mammals and the subsistence hunters; and (2) That 
cannot be sufficiently mitigated by other measures to increase the 
availability of marine mammals to allow subsistence needs to be met.
    The project is unlikely to affect beluga whale harvests because no 
beluga harvest will take place in 2020, nor is one likely to occur in 
the other years that would be covered by the 5-year regulations and 
associated LOAs.
    The proposed Marine Terminal construction activities would occur 
closest to the marine subsistence area used by Nikiski, while the 
offshore pipeline and Beluga Mainline MOF would occur within the 
subsistence use area used by Tyonek. However, the proposed action area 
is not an important native subsistence site for subsistence harvest of 
marine mammals because subsistence hunt is only conducted 
opportunistically. Also, because of the relatively small proportion of 
marine mammals utilizing Cook Inlet, the number harvested is expected 
to be extremely low (NMFS, 2013c). Therefore, AGDC's program is not 
expected to have an impact on the subsistence use of marine mammals.
    Nevertheless, AGDC is required to and has prepared a Stakeholder 
Engagement Plan to involve subsistence communities in the process, 
hearing concerns, and responding to issues. Through the Stakeholder 
Engagement Plan, AGDC would implement the following measures to keep 
subsistence users in the Cook Inlet region informed of its project 
activities.
     Provide a stakeholder engagement specialist as a local 
point of contact;
     Provide informational letters summarizing planned 
activities for summer and winter on a periodic basis to a comprehensive 
list of stakeholders;
     Set up a call-in number for interested marine mammal 
hunters during active construction;
     When requested by stakeholders, as resources allow, attend 
meetings to provide information on upcoming projects; and
     Be available periodically at large-scale events in 
Anchorage for questions from the public and Alaska Native groups, such 
as the Alaska Federation of Natives or Alaska Forum for the 
Environment.
    AGDC has travelled to several operations-related meetings and plans 
to schedule and plans to attend more meetings throughout the 
construction and operation period. AGDC has developed a comprehensive 
stakeholder list of Alaska native communities, organizations, and other 
interested parties in the Cook Inlet region. This list is a ``living'' 
list and will be updated with new stakeholders or as people change 
positions. The updated listed will be submitted to NMFS as part of the 
annual reports.

Adaptive Management

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

Endangered Species Act (ESA)

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

[[Page 50751]]

Resources Division Office, whenever we propose to authorize take for 
endangered or threatened species.
    Pursuant to the MMPA and through these regulations and the 
associated LOA, NMFS is authorizing take of Cook Inlet beluga whale and 
Hawaii, Western North Pacific, and Mexico DPS's of humpback whales, 
which are listed under the ESA.
    The Permit and Conservation Division requested initiation of 
section 7 consultation with the Alaska Region for the promulgation of 
5-year regulations and the subsequent issuance of a Letter of 
Authorization. The Alaska Region issued a Biological Opinion concluding 
that NMFS' action is not likely to adversely affect the listed species 
named above or adversely modify their critical habitat.

Classification

    Pursuant to the procedures established to implement Executive Order 
12866, the Office of Management and Budget has determined that this 
final 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 certified to the Chief Counsel for Advocacy 
of the Small Business Administration at the proposed rule stage that 
this rule, if adopted, would not have a significant economic impact on 
a substantial number of small entities. The AGDC is the only entity 
that would be subject to the requirements in these final regulations. 
During construction, AGDC would employ or contract thousands of people 
and the Alaska LNG Project would generate a market value in the 
billions of dollars. AGDC is not a small governmental jurisdiction, 
small organization, or small business, as defined by the RFA. We did 
not receive any public comments on the certification. Therefore a final 
regulatory flexibility analysis is not required and none has been 
prepared.

List of Subjects in 50 CFR Part 217

    Penalties, Reporting and recordkeeping requirements, Seafood, 
Transportation.

    Dated: July 13, 2020.
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 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 E to part 217 to read as follows:

Subpart E--Taking and Importing Marine Mammals; Alaska Gasline 
Development Corporation Liquefied Natural Gas Facilities 
Construction

Sec.
217.40 Specified activity and specified geographical region.
217.41 Effective dates.
217.42 Permissible methods of taking.
217.43 Prohibitions.
217.44 Mitigation requirements.
217.45 Requirements for monitoring and reporting.
217.46 Letters of Authorization.
217.47 Renewals and modifications of Letters of Authorization.
217.48-217.49 [Reserved]

Subpart E--Taking and Importing Marine Mammals; Alaska Gasline 
Development Corporation Liquefied Natural Gas Facilities 
Construction


Sec.  217.40  Specified activity and specified geographical region.

    (a) Regulations in this subpart apply only to the Alaska Gasline 
Development Corporation (AGDC) or successor entities and those persons 
it authorizes or funds to conduct activities on its behalf for the 
taking of marine mammals that occurs in the area outlined in paragraph 
(b) of this section and that occurs incidental to the activities 
described in paragraph (c) of this section.
    (b) The taking of marine mammals by AGDC may be authorized in a 
Letter of Authorization (LOA) only if it occurs within AGDC's Alaska 
liquefied natural gas (LNG) facilities' construction areas, which are 
located between the Beluga Landing shoreline crossing on the north and 
the Kenai River south of Nikiski on the south in Cook Inlet, Alaska.
    (c) The taking of marine mammals during this project is only 
authorized if it occurs incidental to construction activities 
associated with the proposed LNG facilities or the Mainline crossing of 
Cook Inlet.


Sec.  217.41  Effective dates.

    Regulations in this subpart are effective January 1, 2021 through 
December 31, 2025.


Sec.  217.42  Permissible methods of taking.

    Under LOAs issued pursuant to Sec. Sec.  216.106 of this chapter 
and 217.46, the Holder of the LOAs (hereinafter ``AGDC'') may 
incidentally, but not intentionally, take marine mammals within the 
area described in Sec.  217.40(b) by Level A harassment and Level B 
harassment associated with pile driving and pipe laying activities, 
provided the activity is in compliance with all terms, conditions, and 
requirements of the regulations in this subpart and the applicable 
LOAs.


Sec.  217.43  Prohibitions.

    Notwithstanding takings contemplated in Sec.  217.42 and authorized 
by LOAs issued under Sec. Sec.  216.106 of this chapter and 217.46, no 
person in connection with the activities described in Sec.  217.40 may:
    (a) 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 217.46;
    (b) Take any marine mammal not specified in such LOAs; and
    (c) Take any marine mammal specified in such LOAs in any manner 
other than as specified.


Sec.  217.44  Mitigation requirements.

    When conducting the activities identified in Sec.  217.40(c), the 
mitigation measures contained in any LOAs issued under Sec. Sec.  
216.106 of this chapter and 217.46 must be implemented. These 
mitigation measures must include but are not limited to:
    (a) Time and area restriction. AGDC must follow the following time 
and area restrictions.
    (1) In-water pile driving must occur only during daylight hours. 
Times for other construction activities, such as pipe laying, anchor 
handling, and dredging are not restricted.
    (2) Pile driving associated with the Mainline Material Offloading 
Facility (Mainline MOF) must not occur from June 1 to September 7 (pile 
driving can occur from September 8 to May 31).
    (3) Other than in-water sheet pile driving and pile removal, anchor 
handling, trenching, pipe laying, and vessel transits related to these 
activities, AGDC may not engage in in-water sound-producing activities 
within 10 miles (16 km) of the mean higher high water (MHHW) line of 
the Susitna Delta (Beluga River to the Little Susitna River) between 
April 15 and October 15 which produce sound levels in excess of 120 dB 
rms re 1[micro]Pa @ 1 m.
    (b) Establishment of monitoring and exclusion zones. (1) For all 
relevant in-water construction activity, AGDC must designate Level A 
harassment zones

[[Page 50752]]

with radial distances as identified in any LOA issued under Sec. Sec.  
216.106 of this chapter and 217.46.
    (2) For all relevant in-water construction activity, AGDC must 
designate Level B harassment zones with radial distances as identified 
in any LOA issued under Sec. Sec.  216.106 of this chapter and 217.46.
    (3) For all in-water pile driving work, AGDC must implement an 
exclusion zone for each specific activity as identified in any LOA 
issued under Sec. Sec.  216.106 of this chapter and 217.46. If a marine 
mammal comes within or enters the exclusion zone, AGDC must cease all 
operations.
    (i) For humpback whale and killer whale during in-water pile 
driving activity, the exclusion zones must be based on the Level A 
harassment distances, but must not be less than 10 m from the pile.
    (ii) For harbor porpoise and harbor seal during in-water pile 
driving activity, the exclusion zones must be based on the Level A 
harassment distances up to 1,000 m, but must not be less than 10 m from 
the pile.
    (iii) For Cook Inlet beluga whale during in-water pile driving 
activity, the exclusion zones must be based on the Level B harassment 
distances.
    (iv) A 2,900-m exclusion zone must be established for Cook Inlet 
beluga whale before pipe laying activity associated with anchor 
handling can occur.
    (v) A minimum of 10-m exclusion zone must be established for in-
water construction and heavy machinery not addressed elsewhere in this 
paragraph (b)(3).
    (c) Monitoring of exclusion zones. Pile driving must only take 
place when the exclusion zones are visible and can be adequately 
monitored. If visibility degrades to where the entire exclusion zone 
cannot be effectively monitored during pile driving, AGDC may continue 
to drive the pile section that was being driven to its target depth, 
but may not drive additional sections of pile.
    (d) Shutdown measures. (1) AGDC must deploy protected species 
observers (PSOs) to monitor marine mammals during in-water pile driving 
and pipe laying activities.
    (2) Monitoring must take place from 30 minutes prior to initiation 
of pile driving or pipe laying activities through 30 minutes post-
completion of pile driving or pipe laying activities.
    (i) For pile driving activity, pre-activity monitoring must be 
conducted for 30 minutes to confirm that the exclusion zone is clear of 
marine mammals, and pile driving may commence only if observers have 
declared the exclusion zone clear of marine mammals for that full 
duration of time. Monitoring must occur throughout the time required to 
drive a pile. A determination that the exclusion zone is clear must be 
made during a period of good visibility (i.e., the entire exclusion 
zone and surrounding waters must be visible to the naked eye).
    (ii) If marine mammals are found within the exclusion zone, pile 
driving of the segment must be delayed until they move out of the area. 
If a marine mammal is seen above water and then dives below, the 
contractor must wait 30 minutes for large cetaceans (humpback whale) 
and 15 minutes for small cetaceans (beluga and killer whales and harbor 
porpoise) and pinnipeds. If no marine mammals of that species are seen 
by the observer in that time it can be assumed that the animal has 
moved beyond the exclusion zone.
    (iii) If pile driving of a segment ceases for 30 minutes or more 
and a marine mammal is sighted within the designated exclusion zone 
prior to commencement of pile driving, the observer(s) must notify the 
pile driving operator (or other authorized individual) immediately and 
continue to monitor the exclusion zone. Operations may not resume until 
the marine mammal has exited the exclusion zone or 30 minutes have 
elapsed for large cetaceans or 15 minutes have elapsed for small 
cetaceans and pinnipeds since the last sighting.
    (3) If a marine mammal authorized to be taken by Level B harassment 
enters or approaches the exclusion zone, if a marine mammal not 
specified in the LOAs enters the Level B harassment zone, or if the 
take of a marine mammal species or stock has reached the take limits 
specified in any LOA issued under Sec. Sec.  216.106 of this chapter 
and 217.46 and enters the Level B harassment zone, AGDC must halt all 
construction activities at that location. If construction 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 or Level B harassment zone, 
whichever applicable, or 30 minutes have passed without re-detection of 
the animal if it is a larger cetacean (humpback whale), or 15 minutes 
have passed without re-detection of the animal if it is a small 
cetacean (beluga and killer whales and porpoises) or pinniped.
    (e) Soft start. (1) AGDC must implement soft start techniques for 
impact pile driving. AGDC must conduct an initial set of three strikes 
from the impact hammer at 40 percent energy, followed by a 30-second 
waiting period, then two subsequent three strike sets with associated 
30-seconds waiting periods at the reduced energy.
    (2) Soft start must be required for any impact driving, including 
at the beginning of the day, and at any time following a cessation of 
impact pile driving of 30 minutes or longer.
    (f) Noise attenuation device. For pile-driving at the Mainline MOF 
near the Beluga River, and on the east side of Cook Inlet near Nikiski 
associated with the liquefaction facility, AGDC must deploy air bubble 
curtains around piles. If the sound source verification (SSV) 
measurements indicate that the best-performing bubble curtain 
configuration provides less than a 2 dB reduction in in-water sound 
beyond the bubble curtain, use of the bubble curtain may be 
discontinued.
    (g) Vessel transit. (1) Operators of vessels must, at all times, 
avoid approaching within 100 yards of marine mammals. Operators must 
observe direction of travel of marine mammals and attempt to maintain a 
distance of 100 yards or greater between the animal and the vessel by 
working to alter vessel course or velocity.
    (2) The vessel operator must avoid placing the vessel between 
members of a group of marine mammals in a way that may cause separation 
of individuals in the group from other individuals in that group. A 
group is defined as being three or more whales observed within 500-m of 
one-another and displaying behaviors of directed or coordinated 
activity (e.g., migration or group feeding).
    (3) If the vessel approaches within 1.6 km (1 mi) of one or more 
whales, the vessel operator must take reasonable precautions to avoid 
potential interaction with the whales by taking one or more of the 
following actions, as appropriate:
    (i) Steering to the rear of whale(s) to avoid causing changes in 
their direction of travel.
    (ii) Maintaining vessel speed of 10 knots (19 km/hr) or less when 
transiting to minimize the likelihood of lethal vessel strikes.
    (iii) Reducing vessel speed to less than 5 knots (9 km/hour) within 
274 m (300 yards) of the whale(s).
    (4) Project vessels must remain a minimum of 2.8 km (1.5 nm) 
seaward of the mean lower low water (MLLW) line between the Little 
Susitna River and -150.80 degrees west longitude to minimize the 
impacts of vessel sound and avoid strikes on Cook Inlet beluga whales 
between June 1 and September 7. The Susitna Delta Exclusion Zone is

[[Page 50753]]

defined as the union of the areas defined by:
    (i) A 16-km (10-mile) buffer of the Beluga River thalweg seaward of 
the mean lower low water (MLLW) line;
    (ii) A 16-km (10-mile) buffer of the Little Susitna River thalweg 
seaward of the MLLW line; and
    (iii) A 16-km (10-mile) seaward buffer of the MLLW line between the 
Beluga River and Little Susitna River.
    (iv) The buffer extends landward along the thalweg to include 
intertidal waters within rivers and streams up to their mean higher 
high water line (MHHW). The seaward boundary has been simplified so 
that it is defined by lines connecting readily discernable landmarks.
    (5) For vessels operating in the Susitna Delta Exclusion Zone, the 
following must be implemented:
    (i) All project vessels operating within the designated Susitna 
Delta area must maintain a speed over ground below 4 knots. PSOs must 
note the numbers, date, time, coordinates, and proximity to vessels of 
all belugas observed during operations, and report these observations 
to NMFS in monthly PSO reports.
    (ii) Vessel crew must be trained to monitor for Endangered Species 
Act (ESA)-listed species prior to and during all vessel movements 
within the Susitna Delta Exclusion Zone. The vessel crew must report 
sightings to the PSO team for inclusion in the overall sighting 
database and reports.
    (iii) Vessel operators must not move their vessels when they are 
unable to adequately observe the 100-m zone around vessels under power 
(in gear) due to darkness, fog, or other conditions, unless necessary 
for ensuring human safety.


Sec.  217.95  Requirements for monitoring and reporting.

    (a) Marine mammal visual monitoring--(1) Protected species 
observers. AGDC must employ trained protected species observers (PSO) 
to conduct marine mammal monitoring for its LNG facilities construction 
projects.
    (i) The PSOs must observe and collect data on marine mammals in and 
around the project area for 30 minutes before, during, and for 30 
minutes after all construction work. PSOs must have no other assigned 
tasks during monitoring periods, and must be placed at appropriate and 
safe vantage point(s) practicable to monitor for marine mammals and 
implement shutdown or delay procedures, when applicable, through 
communication with the equipment operator.
    (ii) [Reserved]
    (2) Protected species observer qualifications. AGDC must adhere to 
the following observer qualifications:
    (i) Independent PSOs (i.e., not construction personnel) who have no 
other assigned tasks during monitoring periods must be used;
    (ii) Where a team of three or more PSOs are required, a lead 
observer or monitoring coordinator must be designated. The lead 
observer must have prior experience working as a marine mammal observer 
during construction;
    (iii) Other PSOs may substitute education (degree in biological 
science or related field) or training for experience;
    (iv) AGDC must submit PSO CVs for approval by NMFS prior to the 
onset of pile driving;
    (v) The PSOs must have the ability to conduct field observations 
and collect data according to assigned protocols;
    (vi) The PSOs must have the experience or training in the field 
identification of marine mammals, including the identification of 
behaviors;
    (vii) The PSOs must have sufficient training, orientation, or 
experience with the construction operation to provide for personal 
safety during observations;
    (viii) The PSOs must have 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
    (ix) The PSOs must have the 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.
    (3) Marine mammal monitoring protocols. AGDC must adhere to the 
following marine mammal monitoring protocols:
    (i) For pile driving activities, a minimum of two PSOs must be on 
duty at all times;
    (ii) For pile driving activities, PSOs must be stationed on a bluff 
with minimum height 500 feet above sea level immediately above the 
construction site;
    (iii) For marine mammal monitoring during pipe laying activities, 
at least one PSO must be on the barge and on watch;
    (iv) PSOs may not exceed 4 consecutive watch hours; must have a 
minimum two-hour break between watches; and may not exceed a combined 
watch schedule of more than 12 hours in a 24-hour period;
    (v) PSOs must have no other construction-related tasks while 
conducting monitoring;
    (vi) Monitoring must be conducted from 30 minutes prior to 
commencement of pile driving, throughout the time required to drive a 
pile, and for 30 minutes following the conclusion of pile driving;
    (vii) Monitoring must be conducted from 30 minutes prior to 
commencement of pipe laying activity, throughout the time of pipe 
laying, and for 30 minutes following the conclusion of pipe laying for 
the segment;
    (viii) During all observation periods, PSOs must use high-
magnification (25X), as well as standard handheld (7X) binoculars, and 
the naked eye to search continuously for marine mammals;
    (ix) Monitoring distances must be measured with range finders. 
Distances to animals must be based on the best estimate of the PSO, 
relative to known distances to objects in the vicinity of the PSO; and
    (x) Bearings to animals must be determined using a compass.
    (4) Marine mammal monitoring data collection. PSOs must collect the 
following information during marine mammal monitoring:
    (i) Date and time that monitored activity begins and ends for each 
day conducted (monitoring period);
    (ii) Construction activities occurring during each daily 
observation period, including how many and what type of piles driven 
and distances covered during pipe laying;
    (iii) Deviation from initial proposal in pile numbers, pile types, 
average driving times, and pipe laying distances, etc.;
    (iv) Weather parameters in each monitoring period (e.g., wind 
speed, percent cloud cover, visibility);
    (v) Water conditions in each monitoring period (e.g., sea state, 
tide state);
    (vi) For each marine mammal sighting:
    (A) Species, numbers, and, if possible, sex and age class of marine 
mammals;
    (B) Description of any observable marine mammal behavior patterns, 
including bearing and direction of travel and distance from pile 
driving and pipe laying activities, and notable changes in patterns;
    (C) Location and distance from pile driving and pipe laying 
activities to marine mammals and distance from the marine mammals to 
the observation point; and
    (D) Estimated amount of time that the animals remained in the Level 
A and/or Level B harassment zones;

[[Page 50754]]

    (vii) Description of implementation of mitigation measures within 
each monitoring period (e.g., shutdown or delay); and
    (viii) Other human activity in the area within each monitoring 
period.
    (b) Acoustic monitoring. AGDC must conduct a sound source 
verification (SSV) in accordance with the requirements in the LOA, at 
the beginning of the pile driving to characterize the sound levels 
associated with different pile and hammer types, as well as to 
establish the marine mammal monitoring and mitigation zones.
    (1) A minimum of 2 piles of each type and size must be measured.
    (2) The following data, at minimum, shall be collected during 
acoustic monitoring and reported:
    (i) Hydrophone equipment and methods: Recording device, sampling 
rate, distance from the pile where recordings were made; depth of 
recording device(s);
    (ii) Type of pile being driven and method of driving during 
recordings; and
    (iii) Mean, median, and maximum sound levels (dB re: 1[micro]Pa): 
Cumulative sound exposure level (SELcum), peak sound 
pressure level (SPLpeak), root mean square sound pressure 
level (SPLrms), and single-strike sound exposure level 
(SELs-s).
    (3) An SSV report must be submitted to NMFS within 72 hours after 
field measurements for approval of the results.
    (4) The results of the SSV report may be used to adjust the extent 
of Level A and Level B harassment zones in-water pile driving.
    (c) Reporting measures--(1) Notification. AGDC must notify NMFS 48 
hours prior to the start of each activity in Cook Inlet that may cause 
harassment of marine mammals. If there is a delay in activity, AGDC 
must also notify NMFS as soon as practicable.
    (2) Monthly report. AGDC must submit monthly reports via email to 
NMFS Office of Protected Resources (OPR) and Alaska Regional Office 
(AKRO) for all months with project activities by the 15th of the month 
following the monthly reporting period. The monthly report must contain 
and summarize the following information:
    (i) Dates, times, locations, heading, speed, weather, sea 
conditions (including Beaufort sea state and wind force), and a list of 
all in-water sound-producing activities occurring concurrent with 
marine mammal observations;
    (ii) Species, number, location, distance from the vessel, and 
behavior of all observed marine mammals, as well as associated project 
activity (e.g., number of power-downs and shutdowns), observed 
throughout all monitoring activities;
    (iii) Observation data in paragraphs (a) and (b) of this section 
must be provided in digital spreadsheet format that can be queried;
    (iv) An estimate of the number of animals (by species) exposed to 
sound at received levels greater than or equal to either the Level A or 
Level B harassment thresholds, with a discussion the time spent above 
those received levels and of any specific behaviors those individuals 
exhibited;
    (v) If the extent of Level B harassment zone is beyond visual 
observation, AGDC must also include an appropriate adjustment to 
estimate the total numbers of marine mammals taken based on the portion 
of the areas that are monitored; and
    (vi) A description of the implementation and effectiveness of the 
terms and conditions of the Biological Opinion's Incidental Take 
Statement and mitigation and monitoring measures of the LOA.
    (3) Marine mammal tally numbers. (i) AGDC must keep a tally of the 
estimated number of marine mammals that are taken, based on the number 
of marine mammals observed within the applicable harassment zones, and 
alert NMFS when the authorized limit is close to being met based on 
prescribed monitoring measured in the final rule; and
    (ii) AGDC must keep a tally of the number of marine mammal that are 
sighted during the pile driving and pipe laying activities.
    (4) Beluga whale takes. AGDC must immediately notify NMFS if the 
number of Cook Inlet beluga estimated as taken (based on observed 
exposures above thresholds) reaches 80% of the authorized takes in any 
given calendar year during which take is authorized.
    (5) Annual report. (i) AGDC must submit a comprehensive annual 
report to NMFS within 90 calendar days of the cessation of in-water 
work each year for review. The report must synthesize all sighting data 
and effort during each activity for each year.
    (ii) NMFS will provide comments within 30 days after receiving 
annual reports, and AGDC must address the comments and submit revisions 
within 30 days after receiving NMFS comments.
    (iii) If no comments are received from the NMFS within 30 days, the 
annual report is considered completed.
    (iv) The report must include the following information:
    (A) Summaries of monitoring effort including total hours, 
observation rate by species and marine mammal distribution through the 
study period, accounting for sea state and other factors affecting 
visibility and detectability of marine mammals.
    (B) Analyses of the effects of various factors that may have 
influenced detectability of marine mammals (e.g., sea state, number of 
observers, fog/glare, and other factors as determined by the PSOs).
    (C) Species composition, occurrence, and distribution of marine 
mammal sightings, including date, water depth, numbers, age/size/gender 
categories (if determinable), group sizes, and ice cover.
    (D) Marine mammal observation data with a digital record of 
observation data provided in digital spreadsheet format that can be 
queried.
    (E) Summary of implemented mitigation measures (i.e., shutdowns and 
delays).
    (F) Number of marine mammals during periods with and without 
project activities (and other variables that could affect 
detectability), such as:
    (1) Initial sighting distances versus project activity at the time 
of sighting;
    (2) Closest point of approach versus project activity;
    (3) Observed behaviors and types of movements versus project 
activity;
    (4) Numbers of sightings/individuals seen versus project activity;
    (5) Distribution around the source vessels versus project activity; 
and
    (6) Numbers of animals detected in the exclusion zone.
    (G) Analyses of the effects of project activities on listed marine 
mammals.
    (6) Final report. (i) AGDC must provide NMFS, within 90 days of 
project completion at the end of the five-year period, a report of all 
parameters listed in the monthly and annual report requirements in 
paragraph (c) of this section, noting also all operational shutdowns or 
delays necessitated due to the proximity of marine mammals.
    (ii) NMFS will provide comments within 30 days after receiving this 
report, and AGDC must address the comments and submit revisions within 
30 days after receiving NMFS comments.
    (iii) If no comments are received from the NMFS within 30 days, the 
final report is considered as final.
    (7) Reporting of injured or dead marine mammals. (i) In the 
unanticipated event that the construction or demolition activities 
clearly cause the take of a marine mammal in a prohibited manner, such

[[Page 50755]]

as an injury, serious injury, or mortality, AGDC must immediately cease 
operations with the potential to impact marine mammals in the vicinity 
and immediately report the incident to the NMFS Office of Protected 
Resources, NMFS Alaska Regional Office, and the Alaska Region Stranding 
Coordinators. The report must include the following information:
    (A) Time, date, and location (latitude/longitude) of the incident;
    (B) Description of the incident;
    (C) Status of all sound source use in the 24 hours preceding the 
incident;
    (D) Environmental conditions (e.g., wind speed and direction, sea 
state, cloud cover, visibility, and water depth);
    (E) Description of marine mammal observations in the 24 hours 
preceding the incident;
    (F) Species identification or description of the animal(s) 
involved;
    (G) The fate of the animal(s); and
    (H) Photographs or video footage of the animal (if equipment is 
available).
    (ii) Activities must not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS must work with AGDC to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure Marine Mammal Protection Act (MMPA) 
compliance. AGDC may not resume its activities until notified by NMFS 
via letter, email, or telephone.
    (iii) In the event that AGDC discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition as described in paragraph (c)(7)(iv) 
of this section), AGDC must immediately report the incident to the NMFS 
Office of Protected Resources, NMFS Alaska Regional Office, and the 
Alaska Regional Stranding Coordinators. The report must include the 
same information identified in paragraph (b)(3)(i) of this section. 
Activities may continue while NMFS reviews the circumstances of the 
incident. NMFS will work with AGDC to determine whether modifications 
in the activities are appropriate.
    (iv) In the event that AGDC discovers an injured or dead marine 
mammal, and the lead PSO determines that the injury or death is not 
associated with or related to the activities authorized in the LOA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), AGDC must report the incident to 
the NMFS Office of Protected Resources, NMFS Alaska Regional Office, 
and the Alaska Regional Stranding Coordinators, within 48 hours of the 
discovery. AGDC must provide photographs or video footage (if 
available) or other documentation of the stranded animal sighting to 
NMFS and the Marine Mammal Stranding Network. AGDC may continue its 
operations under such a case.


Sec.  217.46  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to the regulations 
in this subpart, AGDC must apply for and obtain (LOAs) in accordance 
with Sec.  216.106 of this chapter for conducting the activity 
identified in Sec.  217.40(c).
    (b) LOAs, unless suspended or revoked, may be effective for a 
period of time not to extend beyond the expiration date of the 
regulations in this subpart.
    (c) If an LOA(s) expires prior to the expiration date of the 
regulations in this subpart, AGDC may apply for and obtain a renewal of 
the LOA(s).
    (d) In the event of projected changes to the activity or to 
mitigation, monitoring, reporting (excluding changes made pursuant to 
the adaptive management provision of Sec.  217.47(c)(1)) required by an 
LOA, AGDC must apply for and obtain a modification of LOAs as described 
in Sec.  217.47.
    (e) Each LOA must set forth:
    (1) Permissible methods of incidental taking;
    (2) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species, their habitat, and the availability of the 
species for subsistence uses; and
    (3) Requirements for monitoring and reporting.
    (f) Issuance of the LOA(s) must be based on a determination that 
the level of taking must be consistent with the findings made for the 
total taking allowable under the regulations in this subpart.
    (g) Notice of issuance or denial of the LOA(s) must be published in 
the Federal Register within 30 days of a determination.


Sec.  217.47  Renewals and modifications of Letters of Authorization.

    (a) An LOA issued under Sec. Sec.  216.106 of this chapter and 
217.46 for the activity identified in Sec.  217.40(c) must 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 the regulations in this subpart 
(excluding changes made pursuant to the adaptive management provision 
in paragraph (c)(1) of this section); and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOA(s) under the regulations in this 
subpart were implemented.
    (b) For LOA modification or renewal requests by the applicant that 
include changes to the activity or the mitigation, monitoring, or 
reporting measures (excluding changes made pursuant to the adaptive 
management provision in paragraph (c)(1) of this section) that do not 
change the findings made for the regulations in this subpart 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) An LOA issued under Sec. Sec.  216.106 of this chapter and 
217.46 for the activity identified in Sec.  217.40(c) may be modified 
by NMFS under the following circumstances:
    (1) Adaptive management. After consulting with AGDC regarding the 
practicability of the modifications, NMFS may modify (including by 
adding or removing measures) the existing mitigation, monitoring, or 
reporting measures if doing so creates a reasonable likelihood of more 
effectively accomplishing the goals of the mitigation and monitoring 
set forth in the regulations in this subpart.
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in an LOA:
    (A) Results from AGDC's monitoring from the previous year(s);
    (B) Results from other marine mammal and/or sound research or 
studies; or
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent or number not authorized by the regulations in this 
subpart or subsequent LOAs.
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
must publish a notice of proposed LOA in the Federal Register and 
solicit public comment.

[[Page 50756]]

    (2) Emergencies. 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 LOAs issued pursuant to Sec. Sec.  216.106 
of this chapter and 217.46, an LOA may be modified without prior notice 
or opportunity for public comment. Notice would be published in the 
Federal Register within 30 days of the action.


Sec.  Sec.  217.48-217.49   [Reserved]

[FR Doc. 2020-15404 Filed 8-14-20; 8:45 am]
BILLING CODE 3510-22-P