[Federal Register Volume 89, Number 116 (Friday, June 14, 2024)]
[Notices]
[Pages 51102-51132]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-13000]



[[Page 51101]]

Vol. 89

Friday,

No. 116

June 14, 2024

Part III





 Department of Commerce





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National Oceanic and Atmospheric Administration





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Takes of Marine Mammals Incidental to Specified Activities; Taking 
Marine Mammals Incidental to Furie Operating Alaska, LLC Oil and Gas 
Activities in Cook Inlet, Alaska; Notice

  Federal Register / Vol. 89 , No. 116 / Friday, June 14, 2024 / 
Notices  

[[Page 51102]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XD682]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Furie Operating Alaska, LLC Oil and 
Gas Activities in Cook Inlet, Alaska

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

ACTION: Notice; proposed incidental harassment authorizations; request 
for comments on proposed authorizations and possible renewals.

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SUMMARY: NMFS has received a request from Furie Operating Alaska, LLC 
(Furie) for authorization to take marine mammals incidental to oil and 
gas activities in Cook Inlet, Alaska. Pursuant to the Marine Mammal 
Protection Act (MMPA), NMFS is requesting comments on its proposal to 
issue two consecutive incidental harassment authorizations (IHAs) to 
incidentally take marine mammals during the specified activities. NMFS 
is also requesting comments on a possible one-time, 1-year renewal that 
could be issued for either or both of the two IHAs under certain 
circumstances and if all requirements are met, as described in Request 
for Public Comments at the end of this notice. NMFS will consider 
public comments prior to making any final decision on the issuance of 
the requested MMPA authorizations and agency responses will be 
summarized in the final notice of our decision.

DATES: Comments and information must be received no later than July 15, 
2024.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service and should be submitted via email to 
[email protected]. 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-oil-and-gas. In 
case of problems accessing these documents, please call the contact 
listed below.
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments, including all attachments, must 
not exceed a 25-megabyte file size. All comments received are a part of 
the public record and will generally be posted online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-oil-and-gas without change. All personal 
identifying information (e.g., name, address) voluntarily submitted by 
the commenter may be publicly accessible. Do not submit confidential 
business information or otherwise sensitive or protected information.

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

SUPPLEMENTARY INFORMATION:

Background

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

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an IHA) 
with respect to potential impacts on the human environment. 
Accordingly, NMFS is preparing an Environmental Assessment (EA) to 
consider the environmental impacts associated with the issuance of the 
proposed IHA. NMFS' EA will be made available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-oil-and-gas at the time of publication. We will 
review all comments submitted in response to this notice prior to 
concluding our NEPA process or making a final decision on the IHA 
request.

Summary of Request

    On July 19, 2023, NMFS received a request from Furie for two 
consecutive IHAs to take marine mammals incidental to oil and gas 
activities in Cook Inlet, Alaska. The application was deemed adequate 
and complete on April 5, 2024. Furie's request is for take of 12 
species of marine mammals, by Level B harassment and, for harbor seals, 
Level A harassment. Neither Furie nor NMFS expect serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate.

Description of Proposed Activity

Overview

    From April 1, 2024, through March 31, 2025 (Year 1), and from April 
1, 2025 through March 31, 2026 (Year 2), Furie is planning to conduct 
the following oil and gas activities in Middle Cook Inlet, Alaska. In 
Year 1, Furie proposes to relocate the Enterprise 151 jack-up 
production rig (Enterprise 151 or rig) to the Julius R. Platform (JRP) 
site, install up to two conductor piles using an impact hammer, and 
conduct production drilling of up to two natural gas wells at the JRP 
with the Enterprise 151 rig (or a similar rig) across 45-180 days. 
During Year 2, Furie proposes to relocate the Enterprise 151 rig to the 
JRP site again, potentially install one to two conductor piles using an 
impact hammer (depending on whether either or both of these piles are 
installed or not during Year 1), and conduct additional production 
drilling at the JRP. Furie proposes to conduct the rig towing and pile 
driving activities between April 1 and November 15 each year, but if 
favorable ice conditions occur outside of that period, it may tow the 
rig or pile drive outside of that period. Noise produced by rig towing 
and installation of the conductor piles may result in take, by Level B 
harassment, of marine mammals, and for harbor seals, also Level A 
harassment. Thus references to tugging activities herein refer to

[[Page 51103]]

activities where tugs are under load with the rig.

Dates and Duration

    NMFS anticipates that the proposed Year 1 IHA would be effective 
for 1 year beginning mid-to-late 2024, and the proposed Year 2 IHA 
would be effective for one year beginning mid-to-late 2025. The final 
effective dates would be determined based upon when Furie anticipates 
being able to secure the rig from another operator in Cook Inlet. As 
noted above, Furie expects to conduct the rig towing and pile driving 
activities between April 1 and November 15 each year, but if favorable 
ice conditions occur outside of that period, it may tow the rig or pile 
drive outside of that period. Furie will conduct impact installation of 
conductor piles during daylight hours only, and it will only conduct 
rig towing at night if necessary to accommodate a favorable tide. 
Production drilling may be conducted 24 hours per day.

Specific Geographic Region

    Furie's proposed activities would take place in Cook Inlet, Alaska. 
For the purposes of this project, lower Cook Inlet refers to waters 
south of the East and West Forelands; middle Cook Inlet refers to 
waters north of the East and West Forelands and south of Threemile 
River on the west and Point Possession on the east; and upper Cook 
Inlet refers to waters north and east of Beluga River on the west and 
Point Possession on the east. The JRP is located in middle Cook Inlet, 
approximately 8 miles due south of Tyonek, Alaska, and approximately 10 
miles offshore from the shoreline to the southeast of the JRP.
    The southernmost area of operation during Furie's Year 1 and Year 2 
drilling projects is the Rig Tenders Dock, located in Nikiski, Alaska, 
where the Enterprise 151 rig overwinters. The Rig Tenders Dock is in 
lower Cook Inlet, approximately 2.3 miles south of the East Foreland. 
The northernmost location at which Furie may assume operatorship of the 
Enterprise 151 rig is Hilcorp Alaska LLC's (Hilcorp) Bruce platform, 
located 6.4 miles (10.3 kilometers (km)) northwest of the JRP. Hilcorp 
has stated that they do not intend to conduct work at the Tyonek 
platform in 2024 or 2025, and therefore, Furie does not intend to 
operate or tow the Enterprise 151 north of the Bruce platform. The 
Tyonek platform is within the Susitna Delta Exclusion Zone identified 
in Hilcorp's IHAs (87 FR 62364, October 14, 2022). If Hilcorp does 
conduct work at the Tyonek platform, it would maintain operatorship and 
control of the Enterprise 151 until the tow is underway with lines taut 
and the Enterprise 151 is under tug power. As a result, Hilcorp would 
maintain responsibility for any applicable mitigation measures in their 
current IHA that must be met before a tow may be initiated. Once the 
tow is underway, Furie representatives would take over operatorship of 
the Enterprise 151.
    Furie expects to tow the Enterprise 151 once or twice each season. 
The origin of the first rig tow before Furie's use at the JRP and the 
destination of the tow after use at the JRP is yet to be determined, as 
Hilcorp also intends to use the Enterprise 151 for similar work in the 
same region of Cook Inlet, so Furie and Hilcorp must coordinate the use 
of the Enterprise 151. Furie may assume operatorship of the Enterprise 
151 from Hilcorp mid-season, pass operatorship to Hilcorp mid-season, 
or be the sole operator of the rig if Hilcorp does not use it.
    If Furie is the first to operate the Enterprise 151 in a season, 
the origination of the first tow is likely to begin at the Rig Tenders 
Dock and would end at the JRP. If Furie is the sole operator of the 
Enterprise 151 within a season, the rig would be returned to Rig 
Tenders at the end of the production drilling operation. However, if 
Hilcorp is the first to use the Enterprise 151 rig, the origination of 
Furie's tow could be any of Hilcorp's assets (i.e., platforms or well 
locations within the lease areas operated by Hilcorp). If Hilcorp uses 
the Enterprise 151 after Furie, operatorship and responsibility for the 
rig tow will pass to Hilcorp when it is towed from JRP to one of its 
Cook Inlet assets.
    A map of the specific area in which Furie plans to operate is 
provided in figure 1.

[[Page 51104]]

[GRAPHIC] [TIFF OMITTED] TN14JN24.432

Detailed Description of the Specified Activity

Year 1
    Tug Towing and Positioning- Furie proposes to conduct production 
drilling at the JRP with the Enterprise 151 rig (or a similar rig; see 
Furie's IHA application for additional information about the Enterprise 
151 rig). A jack-up rig is not self-propelled and requires vessels 
(tugs or heavy-lift ships) to transport it to an offshore drilling 
location. The Enterprise 151 has a buoyant triangular hull, allowing it 
to be towed like a barge. The rig will be towed to the JRP by up to 
three ocean-going tugboats. (Table 2 describes potential rig tow 
origins and destinations.) Upon arrival at the JRP, a fourth tugboat 
may join the other three for up to 1 hour to complete the precise 
positioning of the rig next to the JRP. The tugboats are expected to be 
rated between 4,000 horsepower (hp) and 8,000 hp. Specifications of the 
proposed tugs are provided in table 1.

                                         Table 1--Tugboat Specifications
----------------------------------------------------------------------------------------------------------------
             Vessel                    Activity             Length               Width           Gross tonnage
----------------------------------------------------------------------------------------------------------------
M/V Bering Wind.................  Towing and          22 m (72 ft)......  10 m (33 ft)......  144.
                                   positioning the
                                   jack-up rig.
M/V Anna T......................  Towing and          32 m (105 ft).....  11 m (36 ft)......  160.
                                   positioning the
                                   jack-up rig.

[[Page 51105]]

 
M/V Bob Franco..................  Towing and          37 meters (121 ft)  11 meters (36 ft).  196.
                                   positioning the
                                   jack-up rig.
M/V TBD.........................  Positioning the     Unknown...........  Unknown...........  Unknown.
                                   jack-up rig.
----------------------------------------------------------------------------------------------------------------
Note: m= meters, ft= feet.

    Several factors will determine the duration that the tugboats are 
towing the Enterprise 151, including the origin and destination of the 
towing route (e.g., Rig Tenders Dock, the JRP, one of Hilcorp's 
platforms) and the tidal conditions. For safety reasons, a high slack 
tide is required to access the shallow water near the dock at Rig 
Tenders Dock, whether beginning a tow or returning the Enterprise 151. 
In all other locations, a slack tide at either high or low tide is 
required to attach the tugs to the rig and float it off position or to 
position the rig and detach from it. Potential tug power output for 
these scenarios is discussed in further detail in the Estimated Take of 
Marine Mammals section.
    The specific towing origin and destination of the Enterprise 151 
depends on whether Hilcorp contracts to use the Enterprise 151 before 
or after Furie in the same season. For example, Furie may assume 
operatorship of the Enterprise 151 at the beginning of the season from 
the Rig tenders dock, or it may assume operatorship mid-season at one 
of Hilcorp's platforms or drilling locations (rather than at the Rig 
Tenders Dock), and tow the rig to the JRP. However, Hilcorp may assume 
operatorship and begin towing the rig from the JRP to one of their 
platforms or drilling locations. As a result, Furie may tow the rig 
once or twice within the season, beginning at several potential 
locations. However, if Furie operates the Enterprise 151 last, or is 
the only operator, the second tow of the season would return the 
Enterprise 151 to the Rig Tenders Dock. Table 2 displays the potential 
scenarios.

           Table 2--Potential Rig Tow Origins and Destinations
------------------------------------------------------------------------
            Scenario                    Tow #1              Tow #2
------------------------------------------------------------------------
Furie is Sole Operator..........  Furie tows from     Furie tows from
                                   the Rig Tenders     the JRP to the
                                   Dock to the JRP.    Rig Tenders Dock.
Furie Early Season, Hilcorp Late  Furie tows from     Hilcorp tows from
 Season.                           the Rig Tenders     the JRP to a
                                   Dock to the JRP.    Hilcorp-operated
                                                       platform or drill
                                                       site.
Hilcorp Early Season, Furie Late  Furie tows from a   Furie tows from
 Season \1\.                       Hilcorp-operated    the JRP to the
                                   platform or drill   Rig Tenders Dock.
                                   site to the JRP.
------------------------------------------------------------------------
\1\ One potential variation to this scenario may result if Hilcorp
  operates the Enterprise 151 early season and conducts work at the
  Tyonek platform or elsewhere within the North Cook Inlet Unit. The
  Tyonek platform is within the Susitna Delta Exclusion Zone identified
  in Hilcorp's IHAs (87 FR 62364, October 14, 2022). If Hilcorp does
  conduct work at the Tyonek platform, it would maintain operatorship
  and control of the Enterprise 151 until the tow is underway with lines
  taut and the Enterprise 151 is under tug power. As a result, Hilcorp
  would maintain responsibility for any applicable mitigation measures
  in their existing IHA that must be met before a tow may be initiated.
  Once the tow is underway, Furie representatives will take over
  operatorship of the Enterprise 151.

    A tow starting at the Rig Tenders Dock would begin at high slack 
tide, pause near the Offshore Systems Kenai (OSK) Dock to wait for 
currents to slow (up to three hours), then arrive at the JRP at the 
next high slack tide (approximately 12 hours after departure). Once the 
tugs arrive at the JRP, there is a 1- to 2-hour window when the slack 
tide current velocity is slow (1 to 2 knots), allowing the tugs to 
position the Enterprise 151 rig and pin the legs to the bottom. Upon 
return, the tugs would be secured to the Enterprise 151 at the JRP on a 
high slack tide, float off location, and transit south with the 
outgoing tide south towards Nikiski, Alaska. The tow will likely pause 
near OSK to wait for the tide cycle to return to a high flood before 
moving near the Rig Tenders Dock to bring it close to shore on high 
slack. Therefore, the tugs will be under load, typically at half-power 
or less, for up to 14 hours during mobilization to the JRP from Rig 
Tenders or demobilization in reverse order.
    If the rig tow begins at a Hilcorp platform or drill site 
(excluding the northern locations), then the Enterprise 151 may be 
lowered, secured to the tugs, and floated off location during low slack 
to take advantage of the flood tide to tow the rig north or east to the 
JRP. In this scenario, the total tow duration is expected to be 
approximately 8 hours, allowing for the 6 hours between the low slack 
and high slack and an additional 1 to 2 hours to position the rig.
    The tugs may abort the first positioning attempt until favorable 
conditions return if it takes longer than anticipated and the current 
velocity exceeds 3 to 4 knots. If so, the tugs will move the rig 
nearby, where the legs can be temporarily lowered to the seafloor to 
secure it. The tugs will remain close by, jogging in the current until 
the positioning attempt can be resumed. The tugs usually complete the 
positioning on the first attempt, but they may be under power for 
approximately five additional hours if a second attempt is needed.
    The tugs will generally attempt to transport the rig by traveling 
with the tide, except when circumstances threaten human safety, 
property, or infrastructure. The rig may need to be towed against the 
tide to a safe harbor if a slack tide window is missed or extreme 
weather events occur.
    Conductor Pipe Installation--Active wells occupy four of the six 
well slots within the caisson (monopod leg) of the JRP. During Year 1, 
Furie intends to drill up to two natural gas wells, either 
``grassroots'' or ``sidetrack'' wells. A grassroots well requires 
drilling a new wellbore from the surface to the gas-bearing formations, 
and requires all new components from the surface to the bottom depth, 
including a conductor pipe, surface and subsurface casing, cement, 
production liner, tubulars, chokes, sleeves, and a wellhead. A 
sidetrack well is a new branch drilled from within an existing well. A 
sidetrack well requires fewer new

[[Page 51106]]

components because many existing components, such as the conductor 
pipe, surface casing, and wellhead, are re-used.
    The conductor pipe is the uppermost portion of a gas well and 
supports the initial sedimentary part of the well, preventing the 
surface layers from collapsing and obstructing the wellbore. The pipe 
also facilitates the return of cuttings from the drill head and 
supports the wellhead components.
    Furie expects to install a 20-inch conductor pipe in each of the 
two empty well slots in Year 1 but expects to complete only one 
grassroots well and one sidetrack well in Year 1. Furie would install 
the conductor pipe with an impact hammer Delmag D62 impact hammer (see 
Furie's IHA application for additional hammer details). As the pipe is 
driven into the sediment, the sections are connected either by welding 
or drivable quick connections. Once installed, the conductor pipes 
remain a permanent component of the natural gas wells. Installation of 
each conductor pile is anticipated to take approximately 2 days, with 
70 percent of the installation occurring on day 1, and the remaining 30 
percent of the installation occurring on day 2. Furie will conduct the 
pile driving during daylight hours only.
    Drilling Operations--Furie proposes to conduct production drilling 
activities after the conductor pipe installation is complete and the 
Enterprise 151 is positioned at the JRP. Furie expects to drill up to 
two wells each year, which could be any combination of new grassroots 
wells or sidetrack wells, to maintain or increase natural gas 
production levels to meet critical local energy needs.
    After the Enterprise 151 is positioned next to the JRP, the rig 
will jack up so that the hull is initially approximately 5 to 10 ft out 
of the water. To set the spud cans on the bottoms of the legs securely 
into the seafloor and ensure stability, the Enterprise 151 has 
specialized ``preload'' tanks within the hull that are filled with 
seawater and designed to add weight to the hull. The preload is 
conducted while the hull is only slightly out of the water to maintain 
a lower center of gravity until full settling and stability are 
achieved. After preloading, the seawater is discharged, and the hull is 
raised so that the drilling derrick can be cantilevered over the top 
deck of the JRP and positioned over a well slot.
    Offshore support vessels (OSVs) support all operating offshore 
platforms in Cook Inlet throughout the open water season and will be 
used during Furie's planned drilling operations to transport equipment 
and supplies between the OSK Dock and the Enterprise 151. During 
production drilling, an average of two daily vessel trips are expected 
between the OSK Dock and the rig. No take of marine mammals is 
anticipated from the operation of OSVs, and OSVs are not discussed 
further in this application beyond the explanation provided here. 
Because vessels will be in transit, exposure to vessel noise will be 
temporary, relatively brief and will occur in a predictable manner, and 
also the sounds are of relatively lower levels. Elevated background 
noise from multiple vessels and other sources can interfere with the 
detection or interpretation of acoustic cues, but the brief exposures 
to OSVs would be unlikely to disrupt behavioral patterns in a manner 
that would qualify as take.
    Helicopters will transport personnel and supplies from shore to the 
rig and platform during production drilling activities. Helicopters 
would be required to follow the mitigation measures described in the 
Proposed Mitigation section of this notice (e.g., helicopters must 
maintain an altitude of 1,500 ft (457 m)), and therefore, take from 
helicopter activity is not anticipated, and helicopter activity is not 
discussed further aside from the mitigation discussion in the Proposed 
Mitigation section.
    Other potential sources of sound from the Enterprise 151 include 
the operation of the diesel generators, mud and cement pumps, and 
ventilation fans. In 2016, while the Randolph Yost jack-up rig was 
drilling at the JRP, Denes and Austin (2016) characterized drilling and 
mud pumping sound as 158 decibels (dB) root mean square (rms) at 1 m 
and 148.8 dB rms at 1 m, respectively. In 2011, while the Enterprise 
151 was conducting exploration drilling in Furie's Kitchen Lights Unit 
lease area, Marine Acoustics Inc. (2011) performed a sound source 
verification (SSV) near the JRP in water depths ranging from 24.4 to 
27.4 m (80 to 90 ft). The SSV measured sound from the diesel generator 
engines at 137 dB re 1 [mu]Pa rms at 1 meter within the frequency 
bandwidth of 141 to 178 hertz (Hz). The SSV also identified the PZ-10 
mud pump and ventilation fans as minor sources of underwater sound. 
Based on the 137 dB re 1 microPascal ([mu]Pa) rms measured at 1 m, the 
Level B harassment isopleth was estimated to be 50 m from the jack-up 
leg or drill riser. As such, drilling, mud pumping, and generator noise 
are not anticipated to result in take of marine mammals, and these 
activities are not discussed further.
Year 2
    In Year 2, Furie would use the same tugboat arrangement to tow the 
Enterprise 151 to and from the JRP and position it, as described above 
for Year 1. Furie proposes to drill up to two wells in Year 2 that 
could be either new grassroots wells, sidetracks, or a combination of 
each. Furie intends to conduct additional production drilling in Year 2 
at the JRP with the Enterprise 151 rig (or a similar rig). Furie 
expects to install both conductor pipes at the JRP in Year 1, but one 
or both may be installed in Year 2 instead (though no more than two 
will be installed over the course of both seasons because only two well 
slots remain to accept new conductors).
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history of the potentially affected species. NMFS 
fully considered all of this information, and we refer the reader to 
these descriptions, instead of reprinting the information. Additional 
information regarding population trends and threats may be found in 
NMFS' Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and 
more general information about these species (e.g., physical and 
behavioral descriptions) may be found on NMFS' website (https://www.fisheries.noaa.gov/find-species).
    Table 3 lists all species or stocks for which take is expected and 
proposed to be authorized for this activity and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and Endangered Species Act (ESA) and potential biological 
removal (PBR), where known. PBR is defined by the MMPA as the maximum 
number of animals, not including natural mortalities, that may be 
removed from a marine mammal stock while allowing that stock to reach 
or maintain its optimum sustainable population (as described in NMFS' 
SARs). While no serious injury or mortality is anticipated or proposed 
to be authorized here, PBR and annual serious injury and mortality from 
anthropogenic sources are included here as gross indicators of the

[[Page 51107]]

status of the species or stocks and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS' stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS' U.S. 2022 SARs. All values presented in table 3 are the most 
recent available at the time of publication (including from the draft 
2023 SARs) and are available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.

                                            Table 3--Species \1\ Likely Impacted by the Specified Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                       Stock abundance
                                                                                 ESA/MMPA status;      (CV, Nmin, most                      Annual M/SI
           Common name                Scientific name            Stock          strategic (Y/N) \2\    recent abundance         PBR             \4\
                                                                                                         survey) \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                 Order Artiodactyla--Cetacea--Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Eschrichtiidae:
    Gray Whale...................  Eschrichtius          Eastern N Pacific...  -, -, N.............  26,960 (0.05,                   801             131
                                    robustus.                                                         25,849, 2016).
Family Balaenidae:
      Family Balaenopteridae
           (rorquals):
    Fin Whale....................  Balaenoptera          Northeast Pacific...  E, D, Y.............  UND \5\ (UND, UND,              UND             0.6
                                    physalus.                                                         2013).
    Humpback Whale...............  Megaptera             Hawai[revaps]i......  -, -, N.............  11,278 (0.56,                   127           27.09
                                    novaeangliae.                                                     7,265, 2020).
    Humpback Whale...............  Megaptera             Mexico-North Pacific  T, D, Y.............  N/A \6\ (N/A, N/A,              UND            0.57
                                    novaeangliae.                                                     2006).
    Humpback Whale...............  Megaptera             Western North         E, D, Y.............  1,084 \7\ (0.088,               3.4            5.82
                                    novaeangliae.         Pacific.                                    1,007, 2006).
    Minke Whale..................  Balaenoptera          AK..................  -, -, N.............  N/A\8\ (N/A, N/A, N/            UND               0
                                    acutorostrata.                                                    A).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
    Killer Whale.................  Orcinus orca........  Eastern North         -, -, N.............  1,920 (N/A, 1,920,               19             1.3
                                                          Pacific Alaska                              2019).
                                                          Resident.
Killer Whale.....................  Orcinus orca........  Eastern North         -, -, N.............  587 (N/A, 587,                  5.9             0.8
                                                          Pacific Gulf of                             2012).
                                                          Alaska, Aleutian
                                                          Islands and Bering
                                                          Sea Transient.
Pacific White-Sided Dolphin......  Lagenorhynchus        N Pacific...........  -, -, N.............  26,880 (N/A, N/A,               UND               0
                                    obliquidens.                                                      1990).
Family Monodontidae (white
 whales):
    Beluga Whale.................  Delphinapterus        Cook Inlet..........  E, D, Y.............  279 \9\ (0.061,                0.53               0
                                    leucas.                                                           267, 2018).
Family Phocoenidae (porpoises):
    Dall's Porpoise..............  Phocoenoides dalli..  AK..................  -, -, N.............  UND \10\ (UND, UND,             UND              37
                                                                                                      2015).
    Harbor Porpoise..............  Phocoena phocoena...  Gulf of Alaska......  -, -, Y.............  31,046 (0.21, N/A,              UND              72
                                                                                                      1998).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Order Carnivora--Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Otariidae (eared seals and
 sea lions):
    CA Sea Lion..................  Zalophus              U.S.................  -, -, N.............  257,606 (N/A,                14,011            >321
                                    californianus.                                                    233,515, 2014).
    Steller Sea Lion.............  Eumetopias jubatus..  Western.............  E, D, Y.............  49,837 \11\ (N/A,               299             267
                                                                                                      49,837, 2022).
Family Phocidae (earless seals):
    Harbor Seal..................  Phoca vitulina......  Cook Inlet/Shelikof   -, -, N.............  28,411 (N/A,                    807             107
                                                          Strait.                                     26,907, 2018).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy
  (https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/; Committee on Taxonomy (2022)).
\2\ 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.
\3\ NMFS marine mammal SARs online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region.
  CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\4\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
  commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
  associated with estimated mortality due to commercial fisheries is presented in some cases.
\5\ The best available abundance estimate for this stock is not considered representative of the entire stock as surveys were limited to a small portion
  of the stock's range. Based upon this estimate and the Nmin, the PBR value is likely negatively biased for the entire stock.
\6\ Abundance estimates are based upon data collected more than 8 years ago and, therefore, current estimates are considered unknown.
\7\ The best estimates of abundance for the stock (1,084) and the portion of the stock migrating to summering areas in U.S. waters (127) were derived
  from a reanalysis of the 2004-2006 SPLASH data (Wade 2021). Although these data are more than fifteen years old, the estimates are still considered
  valid minimum population estimates.
\8\ Reliable population estimates are not available for this stock. Please see Friday et al. (2013) and Zerbini et al. (2006) for additional information
  on numbers of minke whales in Alaska.

[[Page 51108]]

 
\9\ On June 15, 2023, NMFS released an updated abundance estimate for endangered Cook Inlet beluga whales in Alaska (Goetz et al. 2023). Data collected
  during NOAA Fisheries' 2022 aerial survey suggest that the whale population is stable or may be increasing slightly. Scientists estimated that the
  population size is between 290 and 386, with a median best estimate of 331. In accordance with the MMPA, this population estimate will be incorporated
  into the Cook Inlet beluga whale SAR, which will be reviewed by an independent panel of experts, the Alaska Scientific Review Group. After this
  review, the SAR will be made available as a draft for public review before being finalized.
\10\ The best available abundance estimate is likely an underestimate for the entire stock because it is based upon a survey that covered only a small
  portion of the stock's range.
\11\ Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys.

    As indicated above, all 12 species (with 14 number managed stocks) 
in table 3 temporally and spatially co-occur with the activity to the 
degree that take is reasonably likely to occur. In addition, the 
northern sea otter may be found in Cook Inlet, Alaska. However, 
northern sea otters are managed by the U.S. Fish and Wildlife Service 
and are not considered further in this document.

Gray Whale

    The stock structure for gray whales in the Pacific has been studied 
for a number of years and remains uncertain as of the most recent 
(2022) Pacific SARs (Carretta et al. 2023). Gray whale population 
structure is not determined by simple geography and may be in flux due 
to evolving migratory dynamics (Carretta et al. 2023). Currently, the 
SARs delineate a western North Pacific (WNP) gray whale stock and an 
eastern North Pacific (ENP) stock based on genetic differentiation 
(Carretta et al. 2023). WNP gray whales are not known to feed in or 
travel to upper Cook Inlet (Conant and Lohe, 2023; Weller et al. 2023). 
Therefore, we assume that gray whales near the project area are members 
of the ENP stock.
    An Unusual Mortality Event (UME) for gray whales along the West 
Coast and in Alaska occurred from December 17, 2018 through November 9, 
2023. During that time, 146 gray whales stranded off the coast of 
Alaska. The investigative team concluded that the preliminary cause of 
the UME was localized ecosystem changes in the whale's Subarctic and 
Arctic feeding areas that led to changes in food, malnutrition, 
decreased birth rates, and increased mortality (see https://www.fisheries.noaa.gov/national/marine-life-distress/2019-2023-gray-whale-unusual-mortality-event-along-west-coast-and for more 
information).
    Gray whales occur infrequently in Cook Inlet, but can occur 
seasonally during spring and fall in the lower inlet (Bureau of Ocean 
Energy Management (BOEM) 2021). Migrating gray whales pass through the 
lower inlet during their spring and fall migrations to and from their 
primary summer feeding areas in the Bering, Chukchi, and Beaufort seas 
(Swartz 2018; Silber et al. 2021; BOEM 2021).
    Some gray whales remain in certain coastal areas in the Pacific 
Northwest, including lower Cook Inlet, instead of migrating to the 
Arctic in summer (Moore et al. 2007). Several surveys and monitoring 
programs have sighted gray whales in lower Cook Inlet (Shelden et al. 
2013; Owl Ridge 2014; Lomac-MacNair et al. 2013, 2014; Kendall et al. 
2015, as cited in Weston and SLR 2022). Gray whales are occasionally 
seen in mid- and upper Cook Inlet, Alaska, but they are not common. In 
2020, a young male gray whale was stranded in the Twentymile River near 
Girdwood for over a week before swimming back into Turnagain Arm. The 
whale did not survive and was found dead in west Cook Inlet later that 
month (NOAA Fisheries 2020). One gray whale was sighted in Knik Arm 
near the POA in upper Cook Inlet in May of 2020 during observations 
conducted during construction of the Petroleum and Cement Terminal 
project (61N 2021). The sighting occurred less than a week before the 
reports of the gray whale stranding in the Twentymile River and was 
likely the same animal. In 2021, one small gray whale was sighted in 
Knik Arm near Ship Creek, south of the POA (61N 2022a). Although some 
sightings have been documented in the middle and upper Inlet, the gray 
whale range typically only extends into the lower Cook Inlet region.
Humpback Whale
    Humpback whales have been observed during marine mammal surveys 
conducted in Cook Inlet, with the majority sighted in lower Cook Inlet 
south of Kalgin Island. Eighty-three groups containing an estimated 187 
humpbacks were sighted during the Cook Inlet beluga whale aerial 
surveys conducted by NMFS from 1994 to 2012 (Shelden et al. 2013). 
Surveys conducted north of the forelands have documented small numbers 
in middle Cook Inlet. Vessel-based observers participating in the 
Apache Corporation's 2014 survey operations recorded three humpback 
whale sightings near Moose Point in upper Cook Inlet and two sightings 
near Anchor Point, while aerial and land-based observers recorded no 
humpback whale sightings, including in the upper Inlet (Lomac-MacNair 
et al. 2014). In 2015, during the construction of Furie's platform and 
pipeline, four groups of humpback whales were documented. Another group 
of 6 to 10 unidentified whales, thought to be either humpback or gray 
whales, was sighted approximately 15 km northeast of the JRP. Large 
cetaceans were visible near the project (i.e., whales or blows were 
visible), for 2 hours out of the 1,275 hours of observation conducted 
(Jacobs 2015). During SAExploration's 2015 seismic program, three 
humpback whales were observed in Cook Inlet, including two near the 
Forelands and one in lower Cook Inlet (Kendall et al. 2015 as cited in 
Weston and SLR 2022). Hilcorp did not record any sightings of humpback 
whales from their aerial or rig-based monitoring efforts in 2023 
(Horsley and Larson 2023).
    The most comprehensive photo-identification data available suggest 
that approximately 89 percent of all humpback whales in the Gulf of 
Alaska are from the Hawaii stock, 11 percent are from the Mexico stock, 
and less than 1 percent are from the WNP stock (Wade, 2021). 
Individuals from different stocks are known to intermix in feeding 
grounds. There is no designated critical habitat for humpback whales in 
or near the Project area (86 FR 21082, April 21, 2021), nor does the 
project overlap with any known biologically important areas (BIAs).

Minke Whale

    Minke whales are most abundant in the Gulf of Alaska during summer 
and occupy localized feeding areas (Zerbini et al. 2006). During the 
NMFS annual and semiannual surveys of Cook Inlet, minke whales were 
observed near Anchor Point in 1998, 1999, 2006, and 2021 (Shelden et 
al. 2013, 2015, 2017, 2022; Shelden and Wade 2019) and near Ninilchik 
and the middle of lower Cook Inlet in 2021 (Shelden et al. 2022). 
Minkes were sighted southeast of Kalgin Island and near Homer during 
Apache's 2014 survey (Lomac-MacNair et al. 2014), and one was observed 
near Tuxedni Bay in 2015 (Kendall et al. 2015, as cited in Weston and 
SLR 2022). During Hilcorp's seismic survey in lower Cook Inlet in the 
fall of 2019, eight minke whales were observed (Fairweather Science 
2020). In 2018, no minke whales were observed during observations 
conducted for the Cross Inlet Pipeline (CIPL) project near Tyonek 
(Sitkiewicz et al. 2018). Minke whales were also not recorded during

[[Page 51109]]

Hilcorp's aerial or rig-based monitoring efforts in 2023 (Horsley and 
Larson 2023).

Fin Whale

    Fin whales are usually observed as individuals traveling alone, 
although they are sometimes observed in small groups. Rarely, large 
groups of 50 to 300 fin whales can travel together during migrations 
(NMFS 2010a). Fin whales in Cook Inlet have only been observed as 
individuals or in small groups. Sightings of fin whales in Cook Inlet 
are rare; most occur near the entrance. From 2000 to 2022, 10 sightings 
of 26 estimated individual fin whales in lower Cook Inlet were observed 
during NMFS aerial surveys (Shelden et al. 2013, 2015, 2017, 2022; 
Shelden and Wade 2019). None were observed in the area of Furie's 
proposed drilling project. In the fall of 2019, during Hilcorp's 
seismic survey in lower Cook Inlet, eight sightings of 23 fin whales 
were documented, suggesting greater numbers may use the area in the 
fall than previously estimated (Fairweather Science 2020). Hilcorp did 
not record any sightings of fin whales from their aerial or rig-based 
monitoring efforts in 2023 (Horsley and Larson 2023)

Beluga Whale

    NMFS designated Cook Inlet beluga whales as depleted under the MMPA 
in 2000 and listed the population as endangered under the ESA in 2008 
(73 FR 62919, October 10, 2008) when it failed to recover following a 
moratorium on subsistence harvest (65 FR 34590, May 31, 2000). In April 
2011, NMFS designated critical habitat for the beluga under the ESA (76 
FR 20180, April 11, 2011). NMFS finalized the Conservation Plan for the 
Cook Inlet beluga in 2008 (NMFS 2008a) and the Recovery Plan for Cook 
Inlet beluga whales in 2016 (NMFS 2016a). Between 2008 and 2018, Cook 
Inlet belugas experienced a decline of about 2.3 percent per year (Wade 
et al. 2019). The decline overlaps with the northeast Pacific marine 
heatwave that occurred from 2014 to 2016 in the Gulf of Alaska, 
significantly impacting the marine ecosystem (Suryan et al. 2020, as 
cited in Goetz et al. 2023). The most recent abundance estimate 
calculated an average annual increase between 0.2 and 0.9 percent 
between 2012 and 2022 (Goetz et al. 2023).
    Threats that have the potential to impact this stock and its 
habitat include the following: Changes in prey availability due to 
natural environmental variability, ocean acidification, and commercial 
fisheries; climatic changes affecting habitat; predation by killer 
whales; contaminants; noise; ship strikes; waste management; urban 
runoff; construction projects; and physical habitat modifications that 
may occur as Cook Inlet becomes increasingly urbanized (Moore et al. 
2000, Lowry et al. 2006, Hobbs et al. 2015, NMFS 2016). Another source 
of Cook Inlet beluga whale mortality in Cook Inlet is predation by 
transient-type (mammal-eating) killer whales (NMFS 2016b; Shelden et 
al. 2003). No human-caused mortality or serious injury of Cook Inlet 
beluga whales through interactions with commercial, recreational, and 
subsistence fisheries, takes by subsistence hunters, and or human-
caused events (e.g., entanglement in marine debris, ship strikes) has 
been recently documented and harvesting of Cook Inlet beluga whales has 
not occurred since 2008 (NMFS 2008b).
    Generally, female beluga whales reach sexual maturity at 9 to 12 
years old, while males reach maturity later (O'Corry-Crowe 2009); 
however, this can vary between populations. For example, in Greenland, 
males in a population of beluga whales were found to reach sexual 
maturity at 6 to 7 years of age and females at 4 to 7 years. (Heide-
Joregensen and Teilmann 1994). Suydam (2009) estimated that 50 percent 
of females were sexually mature at age 8.25 and the average age at 
first birth was 8.27 years for belugas sampled near Point Lay. Mating 
behavior in beluga whales typically occurs between February and June, 
peaking in March (Burns and Seaman 1986; Suydam 2009). In the Chukchi 
Sea, the gestation period of beluga whales was determined to be 14.9 
months, with a calving interval of 2 to 3 years and a pregnancy rate of 
0.41, declining after 25 years of age (Suydam 2009). Calves are born 
between mid-June and mid-July and typically remain with the mother for 
up to 2 years of age (Suydam 2009).
    Several studies (Johnson et al. 1989; Klishin et al. 2000; Finneran 
et al. 2002; Erbe 2008; White et al. 1978; Awbrey et al. 1988; Ridgway 
et al. 2001; Finneran et al. 2005; Castellote et al. 2019) describe 
beluga whale hearing capabilities. One study on beluga whales captured 
and released in Bristol Bay, Alaska measured hearing ranges at 4 to 150 
(kilohertz) kHz with greatest variation between individuals at the high 
end of the auditory range in combination with frequencies near the 
maximum sensitivity (Castellote et al. 2014). All animals tested heard 
well up to 128 kHz, with two individuals hearing up to 150 kHz 
(Castellote et al. 2014). Beluga whales are included in the NMFS-
identified mid-frequency functional hearing group.
    The Cook Inlet beluga stock remains within Cook Inlet throughout 
the year (Goetz et al. 2012a). The ecological range of Cook Inlet 
belugas has contracted significantly since the 1970s. From late spring 
to fall, nearly the entire population is now found in the upper inlet 
north of the forelands, with a range reduced to approximately 39 
percent of the size documented in the late 1970s (Goetz et al. 2023). 
The recent annual and semiannual aerial surveys (since 2008) found that 
approximately 83 percent of the population inhabits the area between 
the Beluga River and Little Susitna River during the survey period, 
typically conducted in early June. Some aerial survey counts were 
performed in August, September, and October, finding minor differences 
in the numbers of belugas in the upper inlet compared to June, 
reinforcing the importance of the upper inlet habitat area (Young et 
al. 2023).
    Two areas, consisting of 7,809 square kilometers (km\2\) of marine 
and estuarine environments considered essential for the species' 
survival and recovery, were designated critical habitat. Area 1 of the 
Cook Inlet beluga whale critical habitat encompasses all marine waters 
of Cook Inlet north of a line connecting Point Possession (61.04[deg] 
N, 150.37[deg] W) and the mouth of Threemile Creek (61.08.55[deg] N, 
151.04.40[deg] W), including waters of the Susitna, Little Susitna, and 
Chickaloon Rivers below the mean higher high water line (MHHW). This 
area provides important habitat during ice-free months and is used 
intensively by Cook Inlet beluga between April and November for feeding 
and other biological functions (NMFS 2016a). Critical Habitat Area 2 
encompasses some of the fall and winter feeding grounds in middle Cook 
Inlet.
    Since 1993, NMFS has conducted annual aerial surveys in June, July, 
or August to document the distribution and abundance of beluga whales 
in Cook Inlet. The collective survey results show that beluga whales 
have been consistently found near or in river mouths along the northern 
shores of middle and upper Cook Inlet. In particular, beluga whale 
groups are seen in the Susitna River Delta, Knik Arm, and along the 
shores of Chickaloon Bay. Small groups had also been recorded farther 
south in Kachemak Bay, Redoubt Bay (Big River), and Trading Bay 
(McArthur River) prior to 1996, but very rarely thereafter. Since the 
mid-1990s, most beluga whales have been concentrated in shallow areas 
near river mouths north and east of Beluga River

[[Page 51110]]

and Point Possession (Hobbs et al. 2008). Based on these aerial 
surveys, there is a consistent pattern of beluga whale presence in the 
northernmost portion of Cook Inlet from June to October (Rugh et al. 
2000, 2004a, 2004b, 2005, 2006, 2007).
    Though Cook Inlet beluga whales occur throughout the inlet at any 
time of year, generally they spend the ice-free months in the upper 
Cook Inlet, shifting into deeper waters in middle Cook Inlet in winter 
(Hobbs et al. 2008). In 1999, one beluga whale was tagged with a 
satellite transmitter, and its movements were recorded from June 
through September of that year. Since 1999, 18 beluga whales in upper 
Cook Inlet have been captured and fitted with satellite tags to provide 
information on their movements during late summer, fall, winter, and 
spring. Using location data from satellite-tagged Cook Inlet belugas, 
Ezer et al. (2013) found most tagged whales were in the lower to middle 
inlet during January through March, near the Susitna River Delta from 
April to July) and in the Knik and Turnagain Arms from August to 
December. The transmitters collected data for as little as a few days 
and up to 293 days with at least some data obtained each calendar 
month. None of the tagged belugas left the inlet. All but three 
remained north of the forelands for the duration of transmission, and 
those that traveled south did so only briefly (Shelden et al. 2018).
    In the winter, belugas are more widely dispersed based on aerial 
surveys, opportunistic sighting reports, and tagging results, with 
animals found between Kalgin Island and Point Possession. In November, 
beluga whales remained in Knik Arm, Turnagain Arm, and Chickaloon Bay, 
similar to locations observed in September. Later in winter (January 
into March), belugas were sighted near Kalgin Island and in deeper 
waters offshore. However, even when ice cover exceeds 90 percent in 
February and March, belugas travel into Knik Arm and Turnagain Arm 
(Hobbs et al. 2005).
    During the spring and summer, beluga whales are generally 
concentrated near the warmer waters of river mouths where prey 
availability is high and predator occurrence is low (Moore et al. 
2000). Beluga whales in Cook Inlet are believed to mostly calve between 
mid-May and mid-July, and concurrently breed between late spring and 
early summer (NMFS 2016a), primarily in upper Cook Inlet. Beluga 
movement was correlated with the peak discharge of seven major rivers 
emptying into Cook Inlet. Boat-based surveys from 2005 to the present 
(McGuire and Stephens 2017), and initial results from passive acoustic 
monitoring across the entire inlet (Castellote et al. 2016) also 
support seasonal patterns observed with other methods, and other 
surveys confirm Cook Inlet belugas near the Kenai River during summer 
months (McGuire and Stephens 2017).
    During the summer and fall, beluga whales are concentrated near the 
Susitna River mouth, Knik Arm, Turnagain Arm, and Chickaloon Bay 
(Nemeth et al. 2007) where they feed on migrating eulachon 
(Thaleichthys pacificus) and salmon (Onchorhyncus spp.; Moore et al. 
2000). Data from tagged whales (14 tags between July and March 2000 
through 2003) show beluga whales use upper Cook Inlet intensively 
between summer and late autumn (Hobbs et al. 2005). Critical Habitat 
Area 1 encompasses this summer distribution.
    Using the June aerial survey data from 1994 to 2008, Goetz et al. 
(2012) constructed a model of summer habitat preference for the entire 
Cook Inlet. The model identified a positive geographic association with 
rivers with prey species (primarily eulachon and salmon), shallow tidal 
flats, and sandy substrate and a negative association with sources of 
anthropogenic disturbance. A heat map of the summer habitat was 
generated, with 1 km\2\ cells ranging from 0 to 1.12 belugas per km\2\. 
The areas of highest concentration were the Susitna River delta (from 
the Beluga River to the Little Susitna River), upper Knik Arm, and 
Chickaloon Bay. Each area has generally large salmon runs, shallow 
tidal flats, and little anthropogenic disturbance. The location of the 
JRP and the towing routes between the Rig Tenders Dock and the JRP are 
areas of predicted low density in the summer months.
    As late as October, beluga whales tagged with satellite 
transmitters continued to use Knik Arm and Turnagain Arm and Chickaloon 
Bay, but some ranged into lower Cook Inlet south to Chinitna Bay, 
Tuxedni Bay, and Trading Bay (McArthur River) in the fall (Hobbs et al. 
2005). Data from NMFS aerial surveys, opportunistic sighting reports, 
and satellite-tagged beluga whales confirm they are more widely 
dispersed throughout Cook Inlet during the winter months (November to 
April), with animals found between Kalgin Island and Point Possession. 
In November, beluga whales moved between Knik Arm, Turnagain Arm, and 
Chickaloon Bay, similar to patterns observed in September (Hobbs et al. 
2005). By December, beluga whales were distributed throughout the upper 
to middle Cook Inlet. From January into March, they moved as far south 
as Kalgin Island and slightly beyond in central offshore waters. Beluga 
whales also made occasional excursions into Knik Arm and Turnagain Arm 
in February and March despite ice cover greater than 90 percent (Hobbs 
et al. 2005).
    Wild et al. (2023) delineated a Small and Resident Population BIA 
in Cook Inlet that is active year-round and overlaps Furie's proposed 
project area. The authors assigned the BIA an importance score of 2, an 
intensity score of 2, a data support score of 3, and a boundary 
certainty score of 2. These scores indicate that the BIA is of moderate 
importance and intensity, the authors have high confidence that the 
population is small and resident and in the abundance and range 
estimates of the population, and the boundary certainty is medium (see 
Harrison et al. (2023) for additional information about the scoring 
process used to identify BIAs).
    During Apache's seismic test program in 2011 along the west coast 
of Redoubt Bay, lower Cook Inlet, a total of 33 beluga whales were 
sighted during the survey (Lomac-MacNair et al. 2013). During Apache's 
2012 seismic program in mid-inlet, a total of 151 sightings consisting 
of an estimated 1,463 beluga whales were observed (Lomac-MacNair et al. 
2014). During SAExploration's 2015 seismic program, a total of eight 
sightings of 33 estimated individual beluga whales were visually 
observed during this time period and there were two acoustic detections 
of beluga whales (Kendall et al. 2015). During Harvest Alaska's recent 
CIPL project on the west side of Cook Inlet in between Ladd Landing and 
Tyonek Platform, a total of 143 beluga whale sightings (814 
individuals) were observed almost daily from May 31 to July 11, even 
though observations spanned from May 9 through September 15 (Sitkiewicz 
et al. 2018). There were two beluga whale carcasses observed by the 
project vessels in the 2019 Hilcorp lower Cook Inlet seismic survey in 
the fall which were reported to the NMFS Marine Mammal Stranding 
Network (Fairweather Science 2020). Both carcasses were moderately 
decomposed when they were sighted by the protected species observers 
(PSOs). Daily aerial surveys specifically for beluga whales were flown 
over the lower Cook Inlet region, but no beluga whales were observed. 
In 2023, Hilcorp recorded 21 sightings of more than 125 beluga whales 
during aerial surveys and an additional 21 opportunistic sightings that 
included approximately 81 beluga whales (Horsley and Larson, 2023). 
Hilcorp did not record any sightings of

[[Page 51111]]

beluga whales from their rig-based monitoring efforts (Horsley and 
Larson, 2023)

Killer Whale

    Killer whales from the Alaska Resident stock and the Gulf of 
Alaska, Aleutian Islands, and Bering Sea Transient stock occur in lower 
Cook Inlet but rarely in middle and upper Cook Inlet. Recent studies 
have documented the movements of Alaska Resident killer whales from the 
Bering Sea into the Gulf of Alaska as far north as southern Kodiak 
Island (Muto et al. 2017).
    Killer whales have been sighted near Homer and Port Graham in lower 
Cook Inlet (Shelden et al. 2003, 2022; Rugh et al. 2005). Resident 
killer whales from pods often sighted near Kenai Fjords and Prince 
William Sound have been occasionally photographed in lower Cook Inlet 
(Shelden et al. 2003). The availability of salmon influences when 
resident killer whales are more likely to be sighted in Cook Inlet. 
Killer whales were observed in the Kachemak and English Bay three times 
during aerial surveys conducted between 1993 and 2004 (Rugh et al. 
2005). Transient killer whales were increasingly reported to feed on 
belugas in the middle and upper Cook Inlet in the 1990s.
    During the 2015 SAExploration seismic program near the North 
Foreland, two killer whales were observed (Kendall et al. 2015, as 
cited in Weston and SLR 2022). Killer whales were observed in lower 
Cook Inlet in 1994, 1997, 2001, 2005, 2010, 2012, and 2022 during the 
NMFS aerial surveys (Shelden et al. 2013, 2022). Eleven killer whale 
strandings have been reported in Turnagain Arm: six in May 1991 and 
five in August 1993. During the Hilcorp lower Cook Inlet seismic survey 
in the fall of 2019, 21 killer whales were documented (Fairweather 
Science 2020). Throughout 4 months of observation in 2018 during the 
CIPL project in middle Cook Inlet, no killer whales were observed 
(Sitkiewicz et al. 2018). In September 2021, two killer whales were 
documented in Knik Arm in upper Cook Inlet, near the POA (61N 2022a). 
Hilcorp did not record any sightings of fin whales from their aerial or 
rig-based monitoring efforts in 2023 (Horsley and Larson 2023).

Pacific White-Sided Dolphin

    Pacific white-sided dolphins are common in the Gulf of Alaska's 
pelagic waters and Alaska's nearshore areas, British Columbia, and 
Washington (Ferrero and Walker 1996, as cited in Muto et al. 2022). 
They do not typically occur in Cook Inlet, but in 2019, Castellote et 
al. (2020) documented short durations of Pacific white-sided dolphin 
presence using passive acoustic recorders near Iniskin Bay (6 minutes) 
and at an offshore mooring located approximately midway between Port 
Graham and Iniskin Bay (51 minutes). Detections of vocalizations 
typically lasted on the order of minutes, suggesting the animals did 
not remain in the area and/or continue vocalizing for extended 
durations. Visual monitoring conducted during the same period by marine 
mammal observers on seismic vessels near the offshore recorder did not 
detect any Pacific white-sided dolphins (Fairweather Science 2020). 
These observational data, combined with anecdotal information, indicate 
that there is a small potential for Pacific white-sided dolphins to 
occur in the Project area. On May 7, 2014, Apache Alaska observed three 
Pacific white-sided dolphins during an aerial survey near Kenai. This 
is one of the only recorded visual observations of Pacific white-sided 
dolphins in Cook Inlet; they have not been reported in groups as large 
as those estimated in other parts of Alaska (e.g. 92 animals in NMFS' 
IHAs for Tongass Narrows).

Harbor Porpoise

    Harbor porpoises prefer shallow coastal waters less than 100 m in 
depth (Hobbs and Waite 2010). They are common in nearshore areas of the 
Gulf of Alaska, Shelikof Strait, and lower Cook Inlet (Dahlheim et al. 
2000). Harbor porpoises are often observed in lower Cook Inlet in 
Kachemak Bay and from Cape Douglas to the West Foreland (Rugh et al. 
2005).
    Harbor porpoises have been observed during most aerial surveys 
conducted in Cook Inlet since 1993. They are frequently documented in 
Chinitna and Tuxedni Bays on the west side of lower Cook Inlet (Rugh et 
al. 2005), with smaller numbers observed in upper Cook Inlet between 
April and October. There were 137 groups comprised of 190 individuals 
documented between May and August during Apache's 2012 seismic program 
(Lomac-MacNair et al. 2013). Kendall et al. (2015, as cited in Weston 
and SLR 2022) documented 52 groups comprised of 65 individuals north of 
the Forelands during SAExploration's 2015 seismic survey. Two groups 
totaling three harbor porpoises were observed in the fall of 2019 
during Hilcorp's lower Cook Inlet seismic survey (Fairweather Science 
2020). Four monitoring events were conducted at the POA in Anchorage 
between April 2020 and August 2022, during which 42 groups of harbor 
porpoises comprised of 50 individual porpoises were documented over 285 
days of observation (61N 2021, 2022a, 2022b, and 2022c). One harbor 
porpoise was observed during Hilcorp's monitoring boat-based monitoring 
efforts in June 2023 (Horsley and Larson 2023).

Dall's Porpoise

    The Dall's porpoise range in Alaska includes lower Cook Inlet, but 
very few sightings have been reported in upper Cook Inlet. Observations 
have been documented near Kachemak Bay and Anchor Point (Owl Ridge 
2014; BOEM 2015). Dall's porpoises were observed (two groups of three 
individuals) during Apache's 2014 seismic survey which occurred in the 
summer months (Lomac-MacNair et al. 2014). In August 2015, one Dall's 
porpoise was reported in the mid-inlet north of Nikiski during 
SAExploration's seismic program (Kendall et al. 2015 as cited in Weston 
and SLR 2022). During aerial surveys in Cook Inlet, they were observed 
in Iniskin Bay, Barren Island, Elizabeth Island, and Kamishak Bay 
(Shelden et al. 2013). Ten groups totaling 30 Dall's porpoises were 
observed in the fall of 2019 during Hilcorp's lower Cook Inlet seismic 
survey (Fairweather Science 2020). No Dall's porpoises were observed 
during the CIPL project monitoring program in middle Cook Inlet in 2018 
(Sitkiewicz et al. 2018). Hilcorp recorded one sighting of a Dall's 
porpoise from their rig-based monitoring efforts in the project area in 
2023 (Horsley and Larson, 2023).

Steller Sea Lion

    Most Steller sea lions in Cook Inlet occur south of Anchor Point on 
the east side of lower Cook Inlet, with concentrations near haulout 
sites at Shaw Island and Elizabeth Island and by Chinitna Bay and 
Iniskin Bay on the west side (Rugh et al. 2005). Steller sea lions are 
rarely seen in upper Cook Inlet (Nemeth et al. 2007). About 3,600 sea 
lions use haulout sites in the lower Cook Inlet area (Sweeney et al. 
2017), with additional individuals venturing into the area to forage. 
There is no designated critical habitat for Steller sea lions in the 
mid- or upper inlet, nor are there any known BIAs for Steller sea lions 
within the project area.
    Several surveys and monitoring programs have documented Steller sea 
lions throughout Cook Inlet, including in upper Cook Inlet in 2012 
(Lomac-MacNair et al. 2013), near Cape Starichkof in 2013 (Owl Ridge 
2014), in middle and lower Cook Inlet in 2015 (Kendall et al. 2015, as 
cited in Weston and SLR 2022), in middle Cook Inlet in 2018 (Sitkiewicz 
et al. 2018), in lower

[[Page 51112]]

Cook Inlet in 2019 (Fairweather Science 2020), and near the Port of 
Alaska (POA) in Anchorage in 2020, 2021, and 2022 (61N 2021, 2022a, 
2022b, and 2022c).

California Sea Lion

    The few California sea lions observed in Alaska typically do not 
travel further north than Southeast Alaska. They are often associated 
with Steller sea lion haulouts and rookeries (Maniscalco et al. 2004). 
Sightings in Cook Inlet are rare, with two documented during the Apache 
2012 seismic survey (Lomac-MacNair et al. 2013) and anecdotal sightings 
in Kachemak Bay. None were sighted during the 2019 Hilcorp lower Cook 
Inlet seismic survey (Fairweather Science 2020), the CIPL project in 
2018 (Sitkiewicz et al. 2018), or the 2023 Hilcorp aerial or rig-based 
monitoring efforts (Horsley and Larson, 2023).

Harbor Seal

    In the spring and summer, harbor seals display an affinity for 
coastal haulout areas for feeding, breeding, pupping, and molting, 
while ranging further offshore and outside of Cook Inlet during the 
winter. High-density areas include Kachemak Bay, Iniskin Bay, Iliamna 
Bay, Kamishak Bay, Cape Douglas, and Shelikof Strait. Up to a few 
hundred seals seasonally occur in middle and upper Cook Inlet (Rugh et 
al. 2005), with the highest concentrations found near the Susitna River 
during eulachon and salmon runs (Nemeth et al. 2007; Boveng et al. 
2012), but most remain south of the forelands (Boveng et al. 2012).
    More than 200 haulout sites are documented in lower Cook Inlet 
(Montgomery et al. 2007) and 18 in middle and upper Cook Inlet (London 
et al. 2015). Of the 18 in middle and upper Cook Inlet, nine are 
considered ``key haulout'' locations where aggregations of 50 or more 
harbor seals have been documented. Seven key haulouts are in the 
Susitna River delta, and two are near the Chickaloon River. The two 
haulout locations closest to the JRP are located at Middle Ground 
Shoal, which becomes inundated with water at most high tides (London et 
al. 2015).
    Harbor seals have been sighted in Cook Inlet during every year of 
the aerial surveys conducted by NMFS and during all recent mitigation 
and monitoring programs in lower, middle, and upper Cook Inlet (61N 
2021, 2022a, 2022b, and 2022c; Fairweather Science 2020; Kendall et al. 
2015 as cited in Weston and SLR 2022; Lomac-MacNair et al. 2013, 2014; 
Sitkiewicz et al. 2018).

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Not all marine mammal species have equal 
hearing capabilities (e.g., Richardson et al. 1995; Wartzok and Ketten, 
1999; Au and Hastings, 2008). To reflect this, Southall et al. (2007, 
2019) recommended that marine mammals be divided into hearing groups 
based on directly measured (behavioral or auditory evoked potential 
techniques) or estimated hearing ranges (behavioral response data, 
anatomical modeling, etc.). Note that no direct measurements of hearing 
ability have been successfully completed for mysticetes (i.e., low-
frequency cetaceans). Subsequently, NMFS (2018) described generalized 
hearing ranges for these marine mammal hearing groups. Generalized 
hearing ranges were chosen based on the approximately 65 dB threshold 
from the normalized composite audiograms, with the exception for lower 
limits for low-frequency cetaceans where the lower bound was deemed to 
be biologically implausible and the lower bound from Southall et al. 
(2007) retained. Marine mammal hearing groups and their associated 
hearing ranges are provided in table 4.

           Table 4--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
                                                    Generalized hearing
                  Hearing group                           range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)....  7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed   150 Hz to 160 kHz.
 whales, beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises,    275 Hz to 160 kHz.
 Kogia, river dolphins, Cephalorhynchid,
 Lagenorhynchus cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals).  50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions    60 Hz to 39 kHz.
 and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al. 2006; Kastelein et al. 2009; Reichmuth et al. 
2013). This division between phocid and otariid pinnipeds is now 
reflected in the updated hearing groups proposed in Southall et al. 
(2019).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section provides a discussion of the ways in which components 
of the specified activity may impact marine mammals and their habitat. 
The Estimated Take of Marine Mammals 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 of Marine Mammals section, and the Proposed Mitigation 
section, to draw conclusions regarding the likely impacts of these 
activities on the reproductive success or survivorship of individuals 
and whether those impacts are reasonably expected to, or reasonably 
likely to, adversely affect the species or stock through effects on 
annual rates of recruitment or survival.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far (ANSI 1995). The sound level of an area is 
defined by the total acoustical energy being generated by known and 
unknown sources. These sources may

[[Page 51113]]

include physical (e.g., waves, wind, precipitation, earthquakes, ice, 
atmospheric sound), biological (e.g., sounds produced by marine 
mammals, fish, and invertebrates), and anthropogenic sound (e.g., 
vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al. 1995). The result is that, depending 
on the source type and its intensity, sound from a specified activity 
may be a negligible addition to the local environment or could form a 
distinctive signal that may affect marine mammals.
    The proposed project includes the use of three to four tugs towing 
a jack-up rig as well as impact pile driving of conductor piles. The 
sounds produced by these activities fall into one of two general sound 
types: impulsive and non-impulsive. Impulsive sounds (e.g., explosions, 
sonic booms, impact pile driving) are typically transient, brief (less 
than 1 second), broadband, and consist of high peak sound pressure with 
rapid rise time and rapid decay (ANSI 1986; NIOSH 1998; NMFS 2018). 
Non-impulsive sounds (e.g., machinery operations such as drilling or 
dredging, vibratory pile driving, underwater chainsaws, and active 
sonar systems) can be broadband, narrowband or tonal, brief or 
prolonged (continuous or intermittent), and typically do not have the 
high peak sound pressure with rise/decay time that impulsive sounds do 
(ANSI 1995; NIOSH 1998; NMFS 2018). The distinction between impulsive 
and non-impulsive sound sources is important because they have 
differing potential to cause physical effects, particularly with regard 
to hearing (e.g., Ward 1997 in Southall et al. 2007).
    An impact hammer that operates by repeatedly dropping and/or 
pushing a heavy piston onto a pile to drive the pile into the 
substrate. Sound generated by impact hammers is considered impulsive.
    Towing the rig would emit consistent low levels of noise into a 
small portion of Cook Inlet for an extended period of time. Furie's 
tugging and positioning activities would occur for approximately 20-25 
hours over 2 days at the beginning and end of the drilling season in 
Year 1 and in Year 2. Unlike projects that involve discrete noise 
sources with known potential to harass marine mammals (e.g., pile 
driving, seismic surveys), both the noise sources and impacts from the 
tugs towing the rig are less well documented. The various scenarios 
that may occur during this project extend from tugs in a stationary 
mode positioning the drill rig to pulling the rig at nearly full power 
against strong tides. Our assessments of the potential for harassment 
of marine mammals incidental to Furie's tug activities specified here 
are conservative in light of the general Level B harassment exposure 
thresholds, the fact that NMFS is still in the process of developing 
analyses of the impact that non-quantitative contextual factors have on 
the likelihood of Level B harassment occurring, and the nature and 
duration of the particular tug activities analyzed here.
    The proposed project has the potential to harass marine mammals 
from exposure to noise and the physical presence of working vessels 
(e.g., tug configuration and pile driving equipment) as well as 
associated noise with pile driving and the moving and positioning of 
the rig. In this case, NMFS considers potential for harassment from the 
collective use of these technologies working in a concentrated area 
(relative to the entire Cook Inlet) for an extended period of time (for 
tugging, when making multiple positioning attempts) and noise created 
when moving and positioning the rig using tugs, as well as impact 
installation of the conductor piles. Essentially, the project area will 
become a concentrated work area in an otherwise non-industrial setting 
for a period of several days.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from tugs and pile driving equipment is the primary means 
by which marine mammals may be harassed from Furie's specified 
activities. In general, animals exposed to natural or anthropogenic 
sound may experience physical and psychological effects, ranging in 
magnitude from none to severe (Southall et al. 2007). Generally, 
exposure to pile driving and tugging has the potential to result in 
auditory threshold shifts (TS) and behavioral disturbance (e.g., 
avoidance, temporary cessation of foraging and vocalizing, changes in 
dive behavior). Exposure to anthropogenic noise can also lead to non-
observable physiological responses such as an increase in stress 
hormones. Additional noise in a marine mammal's habitat can mask 
acoustic cues used by marine mammals to carry out daily functions such 
as communication and predator and prey detection. The effects of pile 
driving and tugging noise on marine mammals are dependent on several 
factors, including, but not limited to, sound type (e.g., impulsive vs. 
non-impulsive), the species, age and sex class (e.g., adult male vs. 
mother with calf), duration of exposure, the distance between the sound 
source and the animal, received levels, behavior at time of exposure, 
and previous history with exposure (Wartzok et al. 2003; Southall et 
al. 2007). Here we discuss physical auditory effects (TSs) followed by 
behavioral effects and potential impacts on habitat.
    NMFS defines a noise-induced TS as ``a change, usually an increase, 
in the threshold of audibility at a specified frequency or portion of 
an individual's hearing range above a previously established reference 
level'' (NMFS 2018). The amount of TS is customarily expressed in dB 
(ANSI 1995, Yost 2007). A TS can be permanent (PTS) or temporary (TTS). 
As described in NMFS (2016), there are numerous factors to consider 
when examining the consequence of TS, including, but not limited to, 
the signal temporal pattern (e.g., impulsive or non-impulsive), 
likelihood an individual would be exposed for a long enough duration or 
to a high enough level to induce a TS, the magnitude of the TS, time to 
recovery (seconds to minutes or hours to days), the frequency range of 
the exposure (i.e., spectral content), the hearing and vocalization 
frequency range of the exposed species relative to the signal's 
frequency spectrum (i.e., how animal uses sound within the frequency 
band of the signal; e.g., Kastelein et al. 2014), and the overlap 
between the animal and the source (e.g., spatial, temporal, and 
spectral). When analyzing the auditory effects of noise exposure, it is 
often helpful to broadly categorize sound as either impulsive--noise 
with high peak sound pressure, short duration, fast rise-time, and 
broad frequency content--or non-impulsive. For example, when 
considering auditory effects, impact pile driving is treated as an 
impulsive source. The sounds produced by tugs towing and

[[Page 51114]]

positioning the rig are characterized as non-impulsive sounds.
    Permanent Threshold Shift--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals indicate that a 40 dB TS 
approximates PTS onset (see NMFS 2018 for review). PTS levels for 
marine mammals are estimates, because there are limited empirical data 
measuring PTS in marine mammals (e.g., Kastak et al. 2008), largely due 
to the fact that, for various ethical reasons, experiments involving 
anthropogenic noise exposure at levels inducing PTS are not typically 
pursued or authorized (NMFS 2018).
    Temporary Threshold Shift--TTS is a temporary, reversible increase 
in the threshold of audibility at a specified frequency or portion of 
an individual's hearing range above a previously established reference 
level (NMFS 2018). Based on data from cetacean TTS measurements (see 
Finneran 2015 for a review), a TTS of 6 dB is considered the minimum TS 
clearly larger than any day-to-day or session-to-session variation in a 
subject's normal hearing ability (Schlundt et al. 2000; Finneran et al. 
2002; Finneran 2015). As described in Finneran (2016), marine mammal 
studies have shown the amount of TTS increases with cumulative sound 
exposure level (SELcum) in an accelerating fashion: At low 
exposures with lower SELcum, the amount of TTS is typically 
small and the growth curves have shallow slopes. At exposures with 
higher SELcum, the growth curves become steeper and approach 
linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during times when hearing 
is critical, such as for successful mother/calf interactions, could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al. 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Many studies have examined noise-induced hearing loss in marine 
mammals (see Finneran (2015) and Southall et al. (2019) for summaries). 
For cetaceans, published data on the onset of TTS are limited to the 
captive bottlenose dolphin (Tursiops truncatus), beluga whale, harbor 
porpoise, and Yangtze finless porpoise (Neophocoena asiaeorientalis), 
and for pinnipeds in water, measurements of TTS are limited to harbor 
seals, elephant seals (Mirounga angustirostris), and California sea 
lions. These studies examine hearing thresholds measured in marine 
mammals before and after exposure to intense sounds. The difference 
between the pre-exposure and post-exposure thresholds can be used to 
determine the amount of TS at various post-exposure times. The amount 
and onset of TTS depends on the exposure frequency. Sounds at low 
frequencies, well below the region of best sensitivity, are less 
hazardous than those at higher frequencies, near the region of best 
sensitivity (Finneran and Schlundt 2013). At low frequencies, onset-TTS 
exposure levels are higher compared to those in the region of best 
sensitivity (i.e., a low frequency noise would need to be louder to 
cause TTS onset when TTS exposure level is higher), as shown for harbor 
porpoises and harbor seals (Kastelein et al. 2019a, 2019b, 2020a, 
2020b). In addition, TTS can accumulate across multiple exposures, but 
the resulting TTS will be less than the TTS from a single, continuous 
exposure with the same sound exposure level (SEL; Finneran et al. 2010; 
Kastelein et al. 2014; Kastelein et al. 2015a; Mooney et al. 2009). 
This means that TTS predictions based on the total, cumulative SEL will 
overestimate the amount of TTS from intermittent exposures such as 
sonars and impulsive sources. Nachtigall et al. (2018) and Finneran 
(2018) describe the measurements of hearing sensitivity of multiple 
odontocete species (bottlenose dolphin, harbor porpoise, beluga, and 
false killer whale (Pseudorca crassidens)) when a relatively loud sound 
was preceded by a warning sound. These captive animals were shown to 
reduce hearing sensitivity when warned of an impending intense sound. 
Based on these experimental observations of captive animals, the 
authors suggest that wild animals may dampen their hearing during 
prolonged exposures or if conditioned to anticipate intense sounds. 
Another study showed that echolocating animals (including odontocetes) 
might have anatomical specializations that might allow for conditioned 
hearing reduction and filtering of low-frequency ambient noise, 
including increased stiffness and control of middle ear structures and 
placement of inner ear structures (Ketten et al. 2021). Data available 
on noise-induced hearing loss for mysticetes are currently lacking 
(NMFS 2018).
    Activities for this project include tugging and impact pile 
driving. Tugging is a transient activity, and there would likely be 
pauses in pile driving during each day that it occurs. Given the nature 
of these activities and the fact that many marine mammals are likely 
moving through the project areas and not remaining for extended periods 
of time, the potential for TS declines.
Behavioral Disturbance
    Finally, exposure of marine mammals to certain sounds could result 
in behavioral disturbance (Richardson et al. 1995), not all of which 
constitutes harassment under the MMPA. The onset of behavioral 
disturbance from anthropogenic noise depends on both external factors 
(e.g., characteristics of noise sources and their paths) and the 
receiving animals (e.g., hearing, behavioral state, experience, 
demography) and is difficult to predict (Southall et al. 2007, 2021). 
Currently NMFS uses a received level of 160 dB re 1 micro Pascal 
([mu]Pa) rms to predict the onset of Level B harassment from impulse 
noises (such as impact pile driving), and 120 dB re 1 [mu]Pa (rms) for 
continuous noises (such as operating dynamic positioning (DP) 
thrusters), although in certain circumstances there may be contextual 
factors that alter our assessment. Furie's activity includes the use of 
continuous (tug towing and positioning) and impulsive (impact pile 
driving) sources, and therefore the RMS SPL thresholds of 120 and 160 
dB re 1 [mu]Pa are applicable.
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, moving direction and/or speed, 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding), visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping), avoidance of areas where sound sources are located, and/or 
flight responses. Pinnipeds may increase their haul-out time, possibly 
to avoid in-water disturbance (Thorson and Reyff 2006). These potential 
behavioral

[[Page 51115]]

responses to sound are highly variable and context-specific and 
reactions, if any, depend on species, state of maturity, experience, 
current activity, reproductive state, auditory sensitivity, time of 
day, and many other factors regarding the source eliciting the response 
(Richardson et al. 1995; Wartzok et al. 2004; Southall et al. 2007). 
For example, animals that are resting may show greater behavioral 
change in response to disturbing sound levels than animals that are 
highly motivated to remain in an area for feeding (Richardson et al. 
1995; NRC 2003; Wartzok et al. 2004). 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.
    In consideration of the range of potential effects (PTS to 
behavioral disturbance), we consider the potential exposure scenarios 
and context in which species would be exposed to pile driving and tug-
related activity. Cook Inlet beluga whales may be present in low 
numbers during the work; therefore, some individuals may be reasonably 
expected to be exposed to elevated sound levels, including briefly 
those that exceed the Level B harassment threshold for continuous or 
impulsive noise. However, beluga whales are expected to be transiting 
through the area, given this work is proposed primarily in middle Cook 
Inlet (as described in the Description of Marine Mammals in the Area of 
Specified Activities section), thereby limiting exposure duration, as 
belugas in the area are expected to be headed to or from the 
concentrated foraging areas farther north near the Beluga River, 
Susitna Delta, and Knik and Turnigan Arms. Similarly, humpback whales, 
fin whales, minke whales, gray whales, killer whales, California sea 
lion, and Steller sea lions are not expected to remain in the area of 
the tugs. Dall's porpoise, harbor porpoise, and harbor seal have been 
sighted with more regularity than many other species during oil and gas 
activities in Cook Inlet but due to the transitory nature of porpoises, 
they are unlikely to remain at any particular well site for the full 
duration of the noise-producing activity. Because of this and the 
relatively low-level sources, the likelihood of PTS and TTS over the 
course of the tug activities is discountable. Harbor seals may linger 
or haul-out in the area but they are not known to do so in any large 
number or for extended periods of time (there are no known major haul-
outs or rookeries coinciding with the well sites). Here we find there 
is small potential for TTS over the course of tug activities but again, 
PTS is not likely due to the nature of tugging. Potential for PTS and 
TTS due to pile driving is discussed further in the Estimated Take 
section.
    Given most marine mammals are likely transiting through the area, 
exposure is expected to be brief but, in combination with the actual 
presence of the tug and rig configuration as well as conductor pipe 
pile driving, may result in animals shifting pathways around the work 
site (e.g., avoidance), increasing speed or dive times, or cessation of 
vocalizations. The likelihood of no more than a short-term, localized 
disturbance response is supported by data indicating belugas regularly 
pass by industrialized areas such as the Port of Anchorage; therefore, 
we do not expect abandonment of their transiting route or other 
disruptions of their behavioral patterns. We also anticipate some 
animals may respond with such mild reactions to the project that the 
response would not be detectable. For example, during low levels of tug 
power output (e.g., while tugs may be operating at low power because of 
favorable conditions), the animals may be able to hear the work but any 
resulting reactions, if any, are not expected to rise to the level of 
take.
    While in some cases marine mammals have exhibited little to no 
obviously detectable response to certain common or routine 
industrialized activity (Cornick et al. 2011), it is possible some 
animals may at times be exposed to received levels of sound above the 
Level B harassment threshold. This potential exposure in combination 
with the nature of the tug and rig configuration (e.g., difficult to 
maneuver, potential need to operate at night) and pile driving 
activities means it is possible that take could occur over the total 
estimated period of activities.
Masking
    Since many marine mammals rely on sound to find prey, moderate 
social interactions, and facilitate mating (Tyack 2008), noise from 
anthropogenic sound sources can interfere with these functions, but 
only if the noise spectrum overlaps with the hearing sensitivity of the 
marine mammal (Southall et al. 2007; Clark et al. 2009; Hatch et al. 
2012). Chronic exposure to excessive, though not high-intensity, noise 
could cause masking at particular frequencies for marine mammals that 
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 and/or interpretation 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 fitness for survival and reproduction.
    Masking occurs in the frequency band that the animals utilize. 
Since noises generated from tugs towing and positioning are mostly 
concentrated at low frequency ranges, with a small concentration in 
high frequencies as well, these activities likely have less effect on 
mid-frequency echolocation sounds by odontocetes (toothed whales) such 
as Cook Inlet beluga whales. However, lower frequency noises are more 
likely to affect detection of communication calls and other potentially 
important natural sounds such as surf and prey noise. Low-frequency 
noise may also affect communication signals when they occur near the 
frequency band for noise and thus reduce the communication space of 
animals (e.g., Clark et al. 2009) and cause increased stress levels 
(e.g., 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, in addition to 
individual levels. Masking affects both senders and receivers of the 
signals and, at higher levels for longer durations, could have long-
term chronic effects on marine mammal species and populations. However, 
the noise generated by the tugs will not be concentrated in one 
location or for more than 5 hours per positioning attempt, and up to 
two positioning attempts at the same site. Further, noise generated by 
impact pile driving will be intermittent and will occur over a maximum 
of 2 days per year.

Marine Mammal Habitat Effects

    Furie's proposed activities could have localized, temporary impacts 
on marine mammal habitat, including prey, by increasing in-water sound 
pressure levels and, for pile driving, slightly decreasing water 
quality. Increased noise levels may affect acoustic habitat and 
adversely affect marine mammal prey in the vicinity of the project 
areas (see discussion below). Elevated levels of underwater noise would 
ensonify the project areas where both fishes and

[[Page 51116]]

mammals occur and could affect foraging success.
    The total seafloor area likely impacted by the pile driving 
associated with the project is relatively small compared to the 
available habitat in Cook Inlet. Avoidance by potential prey (i.e., 
fish) of the immediate area due to the temporary loss of this foraging 
habitat is possible. The duration of fish and marine mammal avoidance 
of this area after pile driving stops is unknown, but a rapid return to 
normal recruitment, distribution, and behavior is anticipated. Any 
behavioral avoidance by fish or marine mammals of the disturbed area 
would still leave significantly large areas of fish and marine mammal 
foraging habitat in the nearby vicinity.
    Increased turbidity near the seafloor is not anticipated, as 
installation of the conductor piles would occur within the monopod leg 
of the platform.

Effects on Potential Prey

    Sound may affect marine mammals through impacts on the abundance, 
behavior, or distribution of prey species (e.g., fish). Marine mammal 
prey varies by species, season, and location. Here, we describe studies 
regarding the effects of noise on known marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (e.g., Zelick and Mann 1999; Fay 2009). 
Depending on their hearing anatomy and peripheral sensory structures, 
which vary among species, fishes hear sounds using pressure and 
particle motion sensitivity capabilities and detect the motion of 
surrounding water (Fay et al. 2008). The potential effects of noise on 
fishes depends on the overlapping frequency range, distance from the 
sound source, water depth of exposure, and species-specific hearing 
sensitivity, anatomy, and physiology. Key impacts to fishes may include 
behavioral responses, hearing damage, barotrauma (pressure-related 
injuries), and mortality.
    Fish react to sounds that are especially strong and/or intermittent 
low-frequency sounds, and behavioral responses such as flight or 
avoidance are the most likely effects. Short duration, sharp sounds can 
cause overt or subtle changes in fish behavior and local distribution. 
The reaction of fish to noise depends on the physiological state of the 
fish, past exposures, motivation (e.g., feeding, spawning, migration), 
and other environmental factors. Hastings and Popper (2005) identified 
several studies that suggest fish may relocate to avoid certain areas 
of sound energy. Additional studies have documented effects of pile 
driving on fish; several are based on studies in support of large, 
multiyear bridge construction projects (e.g., Scholik and Yan 2001, 
2002; Popper and Hastings 2009). Several studies have demonstrated that 
impulse sounds might affect the distribution and behavior of some 
fishes, potentially impacting foraging opportunities or increasing 
energetic costs (e.g., Fewtrell and McCauley 2012; Pearson et al. 1992; 
Skalski et al. 1992; Santulli et al. 1999; Paxton et al. 2017). 
However, some studies have shown no or slight reaction to impulse 
sounds (e.g., Pena et al. 2013; Wardle et al. 2001; Jorgenson and 
Gyselman 2009).
    SPLs of sufficient strength have been known to cause injury to fish 
and fish mortality. However, in most fish species, hair cells in the 
ear continuously regenerate and loss of auditory function likely is 
restored when damaged cells are replaced with new cells. Halvorsen et 
al. (2012a) showed that a TTS of 4-6 dB was recoverable within 24 hours 
for one species. Impacts would be most severe when the individual fish 
is close to the source and when the duration of exposure is long. 
Injury caused by barotrauma can range from slight to severe and can 
cause death, and is most likely for fish with swim bladders. Barotrauma 
injuries have been documented during controlled exposure to impact pile 
driving (Halvorsen et al. 2012b; Casper et al. 2013).
    For pile driving, the most likely impact to fishes at the project 
site would be temporary avoidance of the area. The duration of fish 
avoidance of this area after pile driving stops is unknown, but a rapid 
return to normal recruitment, distribution, and behavior is 
anticipated. For tugging activities, much of the tugging would be 
mobile during transport of the rig, and the tugging noise that occurs 
during rig positioning would be temporary, similar to pile driving.
    In summary, given the short daily duration of sound associated with 
individual pile driving events and the relatively small areas being 
affected, as well as the temporary and mostly transitory nature of the 
tugging, Furie's activities are not likely to have a permanent, adverse 
effect on any fish habitat, or populations of fish species. Any 
behavioral avoidance by fish of the disturbed area would still leave 
significantly large areas of fish and marine mammal foraging habitat in 
the nearby vicinity. Thus, we conclude that impacts of the specified 
activities are not likely to have more than short-term adverse effects 
on any prey habitat or populations of prey species. Further, any 
impacts to marine mammal habitat are not expected to result in 
significant or long-term consequences for individual marine mammals, or 
to contribute to adverse impacts on their populations.

Estimated Take of Marine Mammals

    This section provides an estimate of the number of incidental takes 
proposed for authorization through the IHA, which will inform NMFS' 
consideration of ``small numbers,'' the negligible impact 
determinations, and impacts on subsistence uses.
    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).
    Takes proposed for authorization would primarily be by Level B 
harassment, as use of the acoustic sources (i.e., pile driving and tug 
towing and positioning) has the potential to result in disruption of 
behavioral patterns for individual marine mammals. We note here that 
given the slow, predictable, and generally straight path of tug towing 
and positioning, the likelihood of a resulting disruption of marine 
mammal behavioral patterns that would qualify as harassment is 
considered relatively low, however, at the request of the applicant, we 
have quantified the potential take from this activity, analyzed the 
impacts, and proposed its authorization. There is also some potential 
for auditory injury (Level A harassment) to result to phocids because 
of species occurrence and because predicted auditory injury zones are 
larger than for mid-frequency and otariid species. Auditory injury is 
unlikely to occur for low-frequency, mid-frequency, high-frequency, or 
otariid species. The proposed mitigation and monitoring measures are 
expected to minimize the severity of the taking to the extent 
practicable.
    As described previously, no serious injury or mortality is 
anticipated or proposed to be authorized for this activity. Below we 
describe how the proposed take numbers are estimated.

[[Page 51117]]

    For acoustic impacts, generally speaking, we estimate take by 
considering: (1) acoustic thresholds above which NMFS believes the best 
available science indicates marine mammals will be behaviorally 
harassed or incur some degree of permanent hearing impairment; (2) the 
area or volume of water that will be ensonified above these levels in a 
day; (3) the density or occurrence of marine mammals within these 
ensonified areas; and (4) the number of days of activities. We note 
that while these factors can contribute to a basic calculation to 
provide an initial prediction of potential takes, additional 
information that can qualitatively inform take estimates is also 
sometimes available (e.g., previous monitoring results or average group 
size). Below, we describe the factors considered here in more detail 
and present the proposed take estimates.

Acoustic Thresholds

    NMFS recommends the use of acoustic thresholds that identify the 
received level of underwater sound above which exposed marine mammals 
would be reasonably expected to be behaviorally harassed (equated to 
Level B harassment) or to incur PTS of some degree (equated to Level A 
harassment).
    Level B Harassment--Though significantly driven by received level, 
the onset of behavioral disturbance from anthropogenic noise exposure 
is also informed to varying degrees by other factors related to the 
source or exposure context (e.g., frequency, predictability, duty 
cycle, duration of the exposure, signal-to-noise ratio, distance to the 
source), the environment (e.g., bathymetry, other noises in the area, 
predators in the area), and the receiving animals (hearing, motivation, 
experience, demography, life stage, depth) and can be difficult to 
predict (e.g., Southall et al. 2007, 2021, Ellison et al. 2012). Based 
on what the available science indicates and the practical need to use a 
threshold based on a metric that is both predictable and measurable for 
most activities, NMFS typically uses a generalized acoustic threshold 
based on received level to estimate the onset of behavioral harassment. 
NMFS generally predicts that marine mammals are likely to be 
behaviorally harassed in a manner considered to be Level B harassment 
when exposed to underwater anthropogenic noise above root-mean-squared 
pressure received levels (RMS SPL) of 120 dB re 1 [mu]Pa for continuous 
(e.g., vibratory pile driving, drilling) and above RMS SPL 160 dB re 1 
[mu]Pa for non-explosive impulsive (e.g., seismic airguns) or 
intermittent (e.g., scientific sonar) sources. Generally speaking, 
Level B harassment take estimates based on these thresholds are 
expected to include any likely takes by TTS as, in most cases, the 
likelihood of TTS occurs at distances from the source smaller than 
those at which behavioral harassment is likely. TTS of a sufficient 
degree can manifest as behavioral harassment, as reduced hearing 
sensitivity and the potential reduced opportunities to detect important 
signals (conspecific communication, predators, prey) may result in 
changes in behavior patterns that would not otherwise occur.
    Furie's proposed activity includes the use of continuous (tugs 
towing rig) and impulsive (impact pile driving) sources, and therefore 
the RMS SPL thresholds of 120 and 160 dB re 1 [mu]Pa are applicable.
    Level A harassment--NMFS' Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0) 
(Technical Guidance, 2018) identifies dual criteria to assess auditory 
injury (Level A harassment) to five different marine mammal groups 
(based on hearing sensitivity) as a result of exposure to noise from 
two different types of sources (impulsive or non-impulsive). Furie's 
proposed activity includes the use of impulsive (impact pile driving) 
and non-impulsive (tugs towing and positioning rig) sources.
    These thresholds are provided in the table below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS' 2018 Technical Guidance, which may be accessed at: 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

            Table 5--Thresholds Identifying the Onset of PTS
------------------------------------------------------------------------
                                      PTS onset acoustic thresholds *
                                             (received level)
          Hearing group          ---------------------------------------
                                       Impulsive         Non-impulsive
------------------------------------------------------------------------
Low-Frequency (LF) cetaceans....  Cell 1: Lpk,flat:   Cell 2: LE,LF,24h:
                                   219 dB;             199 dB.
                                   LE,LF,24h: 183 dB.
Mid-Frequency (MF) cetaceans....  Cell 3: Lpk,flat:   Cell 4: LE,MF,24h:
                                   230 dB;             198 dB.
                                   LE,MF,24h: 185 dB.
High-Frequency (HF) cetaceans...  Cell 5: Lpk,flat:   Cell 6: LE,HF,24h:
                                   202 dB;             173 dB.
                                   LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW)             Cell 7: Lpk,flat:   Cell 8: LE,PW,24h:
 (underwater).                     218 dB;             201 dB.
                                   LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW)            Cell 9: Lpk,flat:   Cell 10:
 (underwater).                     232 dB;             LE,OW,24h: 219
                                   LE,OW,24h: 203 dB.  dB.
------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever
  results in the largest isopleth for calculating PTS onset. If a non-
  impulsive sound has the potential of exceeding the peak sound pressure
  level thresholds associated with impulsive sounds, these thresholds
  should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa,
  and cumulative sound exposure level (LE) has a reference value of
  1[micro]Pa\2\s. In this table, thresholds are abbreviated to reflect
  American National Standards Institute standards (ANSI 2013). However,
  peak sound pressure is defined by ANSI as incorporating frequency
  weighting, which is not the intent for this Technical Guidance. Hence,
  the subscript ``flat'' is being included to indicate peak sound
  pressure should be flat weighted or unweighted within the generalized
  hearing range. The subscript associated with cumulative sound exposure
  level thresholds indicates the designated marine mammal auditory
  weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
  and that the recommended accumulation period is 24 hours. The
  cumulative sound exposure level thresholds could be exceeded in a
  multitude of ways (i.e., varying exposure levels and durations, duty
  cycle). When possible, it is valuable for action proponents to
  indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that are used in estimating the area ensonified above the 
acoustic thresholds, including source levels and transmission loss (TL) 
coefficient.
    The sound field in the project area is the existing background 
noise plus additional noise from the proposed project. Marine mammals 
are expected to be affected via sound generated by the primary 
components of the project (i.e., pile driving and tug towing and 
positioning). The calculated distance to the farthest Level B 
harassment isopleth is approximately 4,483 m (2.8 miles (mi)).

[[Page 51118]]

    The project includes impact installation of up to two 20-inch 
conductor pipe piles in each year. The monopod leg of the JRP will 
encase the well slot, which will encase the conductor pipes; therefore, 
some attenuation is expected during conductor pipe pile installation. 
However, water-filled isolation casings (such as the well slot and 
caisson at the JRP) are expected to provide limited sound attenuation 
(Caltrans 2015). Due to the well slot's reflective surfaces and the 
monopod leg's caisson inside the JRP, some attenuation of the impact 
noise is expected before reaching the open water. However, lacking 
project-specific empirical data for a 20-inch conductor installed 
within a well slot located within a monopod leg, the unaltered sound 
source levels (SSLs) from U.S. Navy (2015) are used to calculate Level 
A harassment and Level B harassment isopleths.
    For tug activities, as described in 87 FR 27597 (May 9, 2022), 
Hilcorp conducted a literature review of available source level data 
for tugs under load in varying power output scenarios. Table 6 below 
provides values of measured source levels for tugs varying from 2,000 
to 8,200 horsepower. For the purposes of this table, berthing 
activities could include tugs either pushing or pulling a load. The 
SSLs appear correlated to speed and power output, with full power 
output and higher speeds generating more propeller cavitation and 
greater SSLs than lower power output and lower speeds. Additional tug 
source levels are available from the literature but they are not 
specific to tugs under load but rather measured values for tugs during 
activities such as transiting, docking, and anchor pulling. For a 
summary of these additional tug values, see table 7 in Hilcorp's 2022 
IHA application, available at https://www.fisheries.noaa.gov/action/incidental-take-authorization-hilcorp-alaska-llc-oil-and-gas-activities-cook-inlet-alaska-0.

                                                Table 6--Literature Values of Measured Tug Source Levels
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  Source level
                Vessel                  Vessel length   Speed (knots)          Activity            @1 m (re: 1     Horsepower           Reference
                                             (m)                                                   [micro]Pa)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Eagle................................              32             9.6  Towing barge............             173           6,770  Bassett et al. 2012.
Valor................................              30             8.4  Towing barge............             168           2,400  .......................
Lela Joy.............................              24             4.9  Towing barge............             172           2,000  .......................
Pacific Eagle........................              28             8.2  Towing barge............             165           2,000  .......................
Shannon..............................              30             9.3  Towing barge............             171           2,000  .......................
James T Quigg........................              30             7.9  Towing barge............             167           2,000  .......................
Island Scout.........................              30             5.8  Towing barge............             174           4,800  .......................
Chief................................              34            11.4  Towing barge............             174           8,200  .......................
Lauren Foss..........................              45             N/A  Berthing barge..........             167           8,200  Austin et al. 2013.
Seaspan Resolution...................              30             N/A  Berthing at half power..             180           6,000  Roberts Bank Terminal 2
                                                                                                                                  Technical Report 2014.
Seaspan Resolution...................              30             N/A  Berthing at full power..             200           6,000  .......................
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The Roberts Bank Terminal 2 Technical Report (2014), although not 
in Cook Inlet, includes repeated measurements of the same tug operating 
under different speeds and loads. This allows for a comparison of 
source levels from the same vessel at half power versus full power, 
which is an important distinction for Furie's activities, as a small 
fraction of the total time spent by tugs under load will be at greater 
than 50 percent power. The Seaspan Resolution's half-power berthing 
scenario has a sound source level of 180 dB re 1 [mu]Pa at 1 m. In 
addition, the Roberts Bank Report (2014) analyzed 650 tug transits 
under varying load and speed conditions and reported mean tug source 
levels of 179.3 dB re 1 [mu]Pa at 1 m; the 25th percentile was 179.0 dB 
re 1 [mu]Pa at 1 m, and 5th percentile source levels were 184.9 dB re 1 
[mu]Pa at 1 m.
    Based solely on the literature review, a source level of 180 dB for 
a single tug under load would be appropriate. However, Furie's use of a 
three tug configuration would increase the literature source level to 
approximately 185 dB at 1 m (Lawrence et al. 2022, as cited in Weston 
and SLR 2022).
    As described above in the Detailed Description of the Specific 
Activity section, based on in situ measurements of Hilcorp's tug and a 
review of the available literature of tugs under load described above, 
NMFS finds that a source level of 185 dB re 1 [micro]Pa is appropriate 
for Furie's three tug configuration for towing the rig.
    As described above in the Detailed Description of the Specific 
Activity section, Furie may need to use four tugs to position the rig 
at the JRP. The SPLRMS of 185 dB for three tugs at 50 
percent power implies each tug individually has a source level of 180.2 
dB SPLrms because the addition of three equal-intensity 
sound signals adds 4.8 dB to the sound level of a single source 
(Engineering Toolbox 2023). Each doubling of sound intensity adds 3 dB 
to the baseline (Engineering Toolbox 2023), and four tugs represents 
two doublings of a single source. Therefore, adding 6 dB to the 180.2 
dB baseline results in an expected SSL of 186.2 dB rms SPL for the use 
of four tugs. Source levels for each activity are presented in table 7.

                  Table 7--SSLs for Project Activities
------------------------------------------------------------------------
                                                    SSL
          Sound source           ---------------------------------------
                                          SEL               SPLRMS
------------------------------------------------------------------------
3 tugs at 50 percent power......  ..................  185 dB at 1 m.
4 tugs at 50 percent power......  ..................  186.2 dB at 1 m.
Conductor pipe pile (20 in,       184 dB at 1 m.....  193 dB at 10 m.
 impact).
------------------------------------------------------------------------


[[Page 51119]]

    Several factors will determine the duration that the tugboats are 
towing the Enterprise 151, including the origin and destination of the 
towing route (e.g., Rig Tenders Dock, the JRP, one of Hilcorp's 
platforms) and the tidal conditions. The power output will be variable 
and influenced by the prevailing wind direction and velocity, the 
current velocity, and the tidal stage. To the extent feasible, 
transport will be timed with the tide to minimize towing duration and 
power output.
    TL is the decrease in acoustic intensity as an acoustic pressure 
wave propagates out from a source. TL parameters vary with frequency, 
temperature, sea conditions, current, source and receiver depth, water 
depth, water chemistry, and bottom composition and topography. The 
general formula for underwater TL is:

TL = B * Log10 (R1/R2),

Where
TL = transmission loss in dB
B = transmission loss coefficient
R1 = the distance of the modeled SPL from the driven pile, and
R2 = the distance from the driven pile of the initial measurement

    Absent site-specific acoustical monitoring with differing measured 
TL, a practical spreading value of 15 is used as the TL coefficient in 
the above formula. Site-specific TL data for pile driving at the JRP 
site are not available; therefore, the default coefficient of 15 is 
used to determine the distances to the Level A harassment and Level B 
harassment thresholds for conductor pile driving.
    For its tugging activities, Hilcorp contracted SLR Consulting to 
model the extent of the Level B harassment isopleth as well as the 
extent of the Level A harassment isopleth for their proposed tugging 
using three tugs. Rather than applying practical spreading loss, SLR 
Consulting created a more detailed propagation loss model in an effort 
to improve the accuracy of the results by considering the influence of 
environmental variables (e.g., bathymetry) at Hilcorp's specific well 
sites. Modeling was conducted using dBSea software. The fluid parabolic 
equation modeling algorithm was used with 5 Pad[eacute] terms (see pg. 
57 in Hilcorp's application, available at https://www.fisheries.noaa.gov/action/incidental-take-authorization-hilcorp-alaska-llc-oil-and-gas-activities-cook-inlet-alaska-0, for more detail) 
to calculate the TL between the source and the receiver at low 
frequencies (1/3-octave bands, 31.5 Hz up to 1 kHz). For higher 
frequencies (1 kHz up to 8 kHz) the ray tracing model was used with 
1,000 reflections for each ray. Sound sources were assumed to be 
omnidirectional and modeled as points. The received sound levels for 
the project were calculated as follows: (1) One-third octave source 
spectral levels were obtained via reference spectral curves with 
subsequent corrections based on their corresponding overall source 
levels; (2) TL was modeled 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; (3) The bathymetry variation of the vertical plane 
along each modeling path was obtained via interpolation of the 
bathymetry dataset which has 83 m grid resolution; (4) The one-third 
octave source levels and TL were combined to obtain the received levels 
as a function of range, depth, and frequency; and (5) The overall 
received levels were calculated at a 1 m depth resolution along each 
propagation path by summing all frequency band spectral levels.
    Bathymetry data used in the model was collected from the NOAA 
National Centers for Environmental Information (AFSC 2019). Using 
NOAA's temperature and salinity data, sound speed profiles were 
computed for depths from 0 to 100 m for May, July, and October to 
capture the range of possible sound speed depending on the time of year 
Hilcorp's work could be conducted. These sound speed profiles were 
compiled using the Mackenzie Equation (1981) and are presented in table 
8 of Hilcorp's application (available at https://www.fisheries.noaa.gov/action/incidental-take-authorization-hilcorp-alaska-llc-oil-and-gas-activities-cook-inlet-alaska-0). Geoacoustic 
parameters were also incorporated into the model. The parameters were 
based on substrate type and their relation to depth. These parameters 
are presented in table 9 of Hilcorp's application (available at https://www.fisheries.noaa.gov/action/incidental-take-authorization-hilcorp-alaska-llc-oil-and-gas-activities-cook-inlet-alaska-0).
    Detailed broadband sound TL modeling in dBSea used the source level 
of 185 dB re 1 [mu]Pa at 1 m calculated in one-third octave band levels 
(31.5 Hz to 64,000 Hz) for frequency dependent solutions. The 
frequencies associated with tug sound sources occur within the hearing 
range of marine mammals in Cook Inlet. Received levels for each hearing 
marine mammal group based on one-third octave auditory weighting 
functions were also calculated and integrated into the modeling 
scenarios of dBSea. For modeling the distances to relevant PTS 
thresholds, a weighting factor adjustment was not used; instead, the 
data on the spectrum associated with their source was used and 
incorporated the full auditory weighting function for each marine 
mammal hearing group.
    Furie plans to use the tugs towing the rig for two functions, rig 
positioning and towing. The activity was divided into two parts 
(stationary and mobile) and two approaches were taken for modeling the 
relevant isopleths.
    SLR's model, described above, calculated the Level B harassment 
isopleth propagating from three tugs towing a jack-up rig at 25 
locations between Hilcorp platforms and well sites and the Rig Tenders 
Dock in Nikiski, Alaska. The average Level B harassment isopleth across 
all locations and seasons was determined to be 3,850 m (Weston and SLR 
2022). Given that Furie is conducting the same three tug activity as 
Hilcorp, also in middle Cook Inlet, Furie estimates, and NMFS concurs, 
that 3,850 m is also an appropriate estimate of its Level B harassment 
zone for tugging using three tugs. Similarly, Hilcorp modeled Level A 
harassment zones for each hearing group; Furie proposed using these 
Level A harassment zones for its towing and positioning activities 
using three tugs, and NMFS concurs. These zones are included in table 
8.
    As described in the Description of Proposed Activity section, when 
positioning the rig, Furie may use four tugs for up to 1 hour. Hilcorp 
did not model a Level B harassment zone accounting for the use of four 
tugs. Furie estimated the Level B harassment zones for tugging and 
positioning with four tugs using a sound source level of 186.2 dB and a 
TL of 18.129.
    NMFS estimated the Level A harassment zones from the use of four 
tugs using its User Spreadsheet and the Level A harassment zones 
modeled by Hilcorp for the use of three tugs. First, NMFS calculated 
the Level A harassment zones for the three tug scenario using the User 
Spreadsheet (sound source level of 185 dB, 5 hours of sound production, 
and a propagation loss coefficient of 18.129). Next, NMFS calculated 
the Level A harassment zones for the ``combined scenario'' (use of 
three tugs for 5 hours and four tugs for 1 hour, combined). NMFS then 
calculated the ratio between the three tug scenario and the combined 
scenario. For all hearing groups the combined scenario Level A 
harassment isopleths are 13.8 percent larger than the three tug 
scenario. Rather than using the Level A harassment isopleths for the 
combined

[[Page 51120]]

scenario that were calculated using the User Spreadsheet, NMFS applied 
a 13.8 percent increase to the three tug Level A harassment isopleths 
modeled by Hilcorp, given that those isopleths are more conservative 
than the isopleths NMFS calculated using the User Spreadsheet. The 
Level A harassment isopleths that Furie will implement are included in 
table 10.
    The Level B harassment isopleth from the use of four tugs is 4,483 
m, as described in Furie's application and included in table 6, 
calculated using a sound source level of 186.2 dB SPL. NMFS concurs and 
proposes a Level B harassment zone of 4,483 m for tugging and 
positioning using four tugs (table 10).

                      Table 8--User Spreadsheet Inputs (Source Levels Provided in Table 7)
----------------------------------------------------------------------------------------------------------------
                                                                     Number of                     Transmission
                             Source                                 strikes per      Number of         loss
                                                                       pile        piles per day    coefficient
----------------------------------------------------------------------------------------------------------------
Conductor pipe pile, Day 1 (70 percent installation)............           6,100             0.7              15
Conductor pipe pile, Day 2 (30 percent installation)............                             0.3
----------------------------------------------------------------------------------------------------------------


 Table 9--Level A Harassment Isopleths Calculated Using NMFS' User Spreadsheet, and Used To Determine the Ratio
                    Between the Three Tug Scenario and Three and Four Tugs Combined Scenario
----------------------------------------------------------------------------------------------------------------
                                                          Level A harassment isopleth (m)
                                 -------------------------------------------------------------------------------
            Scenario                                                   High-
                                  Low- Frequency  Mid- Frequency     Frequency        Phocid          Otariid
                                     Cetaceans       Cetaceans       Cetaceans       Pinnipeds       Pinnipeds
----------------------------------------------------------------------------------------------------------------
Three Tug Scenario Level A                  17.2             9.7           178.9             9.1             0.9
 harassment Isopleth............
Combined Scenario Level A                   19.6            11.0           203.6            10.3             1.0
 harassment Isopleth............
----------------------------------------------------------------------------------------------------------------

    The ensonified area associated with Level A harassment is more 
technically challenging to predict due to the need to account for a 
duration component. Therefore, NMFS developed an optional User 
Spreadsheet tool to accompany the Technical Guidance that can be used 
to relatively simply predict an isopleth distance for use in 
conjunction with marine mammal density or occurrence to help predict 
potential takes. We note that because of some of the assumptions 
included in the methods underlying this optional tool, we anticipate 
that the resulting isopleth estimates are typically overestimates of 
some degree, which may result in an overestimate of potential take by 
Level A harassment. However, this optional tool offers the best way to 
estimate isopleth distances when more sophisticated modeling methods 
are not available or practical. For stationary sources such as 
conductor pipe pile driving and rig positioning, the optional User 
Spreadsheet tool predicts the distance at which, if a marine mammal 
remained at that distance for the duration of the activity, it would be 
expected to incur PTS. For mobile sources such as tugging, the optional 
User Spreadsheet tool predicts the closest distance at which a 
stationary animal would not be expected to incur PTS if the sound 
source traveled by the stationary animal in a straight line at a 
constant speed. Inputs used in the optional User Spreadsheet tool, and 
the resulting estimated isopleths, are reported below.

                           Table 10--Level A Harassment and Level B Harassment Isopleths From Tugging and Impact Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Level A                            Level B harassment isopleths  (m)
                      Sound source                          harassment   -------------------------------------------------------------------------------
                                                          isopleths  (m)        LF              MF              HF              PW              OW
--------------------------------------------------------------------------------------------------------------------------------------------------------
Conductor pipe pile, 70 percent installation............           3,064             109           3,650           1,640             119           1,585
Conductor pipe pile, 30 percent installation............           1,742              62           2,075             932              68
Tugging/Positioning, 3 Tugs \1\.........................              95              78             679              69               0           3,850
Tugging/Positioning, 4 Tugs \2\.........................             108              89             773              79               1           4,483
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ These zones are results from Hilcorp's modeling.
\2\ For otariids, Hilcorp's model estimated a Level A harassment zone of 0 during tugging/positioning with three tugs. Therefore, for four tugs, NMFS
  applied the Level A harassment zone calculating with the User Spreadsheet.

Marine Mammal Occurrence

    In this section we provide information about the occurrence of 
marine mammals, including density or other relevant information which 
will inform the take calculations.
    Densities for marine mammals in Cook Inlet were derived from NMFS' 
Marine Mammal Laboratory (MML) aerial surveys, typically flown in June, 
from 2000 to 2018 (Rugh et al. 2005; Shelden et al. 2013, 2015, 2017, 
2019). While the surveys are concentrated for a few days in June 
annually, which may skew densities for seasonally present species, they 
are still the best available long-term dataset of marine mammal 
sightings available in Cook Inlet. (Note that while more recent surveys 
have been conducted and published (Shelden et al. 2022; Goetz et al. 
2023), the surveyed area was not included in either report, therefore 
they were not used to calculate density). Density was calculated by 
summing the total number of animals observed and dividing the number 
sighted by the area surveyed.

[[Page 51121]]

The total number of animals observed accounts for both lower and upper 
Cook Inlet. There are no density estimates available for California sea 
lions and Pacific white-sided dolphins in Cook Inlet, as they are so 
infrequently sighted. Densities are presented in table 11.

                    Table 11--Marine Mammal Densities
------------------------------------------------------------------------
                                                    Density (individuals/
                      Species                              km\2\)
------------------------------------------------------------------------
Humpback whale....................................               0.00177
Minke whale.......................................              0.000009
Gray whale........................................              0.000075
Fin whale.........................................              0.000311
Killer whale......................................              0.000601
Beluga (Trading Bay)..............................     0.004453-0.015053
Beluga (North Cook Inlet).........................              0.001664
Dall's porpoise...................................              0.000154
Harbor porpoise...................................              0.004386
Pacific white-sided dolphin.......................                     0
Harbor seal.......................................              0.241401
Steller sea lion..................................              0.007609
California sea lion...............................                     0
------------------------------------------------------------------------

    For the beluga whale density, Furie, and subsequently NMFS, used 
the Goetz et al. (2012) habitat-based model. This model is derived from 
sightings and incorporates depth soundings, coastal substrate type, 
environmental sensitivity index, anthropogenic disturbance, and 
anadromous fish streams to predict densities throughout Cook Inlet. The 
output of this model is a beluga density map of Cook Inlet, which 
predicts spatially explicit density estimates for Cook Inlet belugas. 
Using the resulting grid densities, average densities were calculated 
for two regions applicable to Furie's operations. The densities 
applicable to the area of activity (i.e., the North Cook Inlet Unit 
density for middle Cook Inlet activities and the Trading Bay density 
for activities in Trading Bay) are provided in table 11 and were 
carried forward to the take estimates. Likewise, when a range is given, 
the higher end of the range was conservatively used to calculate take 
estimates (i.e., Trading Bay in the Goetz model has a range of 0.004453 
to 0.015053; 0.015053 was used for the take estimates).

Take Estimation

    Here we describe how the information provided above is synthesized 
to produce a quantitative estimate of the take that is reasonably 
likely to occur and proposed for authorization in each IHA.
Year 1 IHA
    As described above, Furie plans to conduct rig towing and 
positioning and may install up to two conductor piles using an impact 
hammer in Year 1. To estimate take by Level B harassment from tugging, 
for each species, Furie summed the estimated take for towing the rig at 
the beginning of the season, positioning the rig, and towing the rig at 
the end of the season. To estimate take for towing the rig (beginning 
and end of season), Furie multiplied the area of the Level B harassment 
zone (316.1 km\2\; inclusive of the full potential tug path of 35 km) 
by the species density (table 11). To estimate take for positioning the 
rig, Furie multiplied the maximum area of the Level B harassment zone 
(63.1 km\2\, four tugs) by the species density (table 11), by the 
number of potential positioning attempts (two attempts). NMFS concurs 
that this method for estimating take from tugging activities is 
appropriate.
    To estimate take by Level B harassment from installation of 
conductor piles, Furie multiplied the Level B harassment zone (7.98 
km\2\) by the species density (table 11) by the estimated number of 
days that conductor pile installation would occur (4 days, 2 per pile). 
The Level B harassment zone used in the calculation conservatively 
assumes 70 percent installation of a conductor pile on a given day, and 
therefore, on 2 of the 4 days that conductor piles would be installed, 
the Level B harassment zone would likely be smaller. NMFS concurs that 
this method for estimating take from pile driving activities is 
appropriate.
    NMFS summed the estimated take by Level B harassment from tugging 
and pile driving activities for each species. For species where the 
total calculated take by Level B harassment is less than the estimated 
group size for that species, NMFS rounded up the take by Level B 
harassment proposed for authorization to the anticipated group size. 
Take proposed for authorization during Year 1 activities is included in 
table 12.
    Based on the analysis described above, NMFS does not propose to 
authorize take by Level A harassment related to Furie's tugging 
activity. For mobile tugging activity, the distances to the PTS 
thresholds for high frequency cetaceans (the only hearing group for 
which modeling results in a Level A harassment zone greater than 0 m) 
are smaller than the overall size of the tug and rig configuration, 
making it unlikely a cetacean would remain close enough to the tug 
engines for a long enough duration to incur PTS. For stationary 
positioning of the rig, the PTS isopleths are up to 679 m for high 
frequency cetaceans, but calculated with the assumption that an animal 
would remain within several hundred meters of the rig for the full 5 
hours of noise-producing activity which is unlikely. Therefore, take by 
Level A harassment due to stationary or mobile tugging is neither 
anticipated nor proposed for authorization.
    For conductor pile installation, NMFS anticipates take by Level A 
harassment for harbor seal only. For all other species, calculated take 
by Level A harassment takes is less than one. Considering that along 
with the low likelihood that an individual of these species would enter 
and remain within the Level A harassment zone for long enough to incur 
PTS, particularly in consideration of implementation of required 
shutdown zones, Furie did not request, nor does NMFS propose to 
authorize, take by Level A harassment. For harbor seal, NMFS proposes 
to authorize three takes by Level A harassment, conservatively rounded 
up from 2.7 Level A harassment takes calculated.

                                                   Table 12--Estimated Take by Level B Harassment, by Species, Activity, and in Total, Year 1
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                          Rig tow, 3 tugs             Rig positioning, 4 tugs       Conductor pile installation
                                                                 ------------------------------------------------------------------------------------------------  Total year 1
                                                                                    Calculated                      Calculated                      Calculated    estimated take   Proposed take
                             Species                                Ensonified     take by Level    Ensonified     take by Level    Ensonified     take by Level    by Level B      by Level B
                                                                   area (km\2\)    B harassment    area (km\2\)    B harassment    area (km\2\)    B harassment     harassment    harassment \a\
                                                                        \1\             \2\                             \3\                             \4\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale..................................................           316.1             1.2            63.1             0.2            7.89            0.06             1.5               3
Minke whale.....................................................  ..............           0.006  ..............           0.001  ..............          0.0003           0.007               3
Gray whale......................................................  ..............            0.04  ..............           0.009  ..............           0.002            0.05               3
Fin whale.......................................................  ..............             0.2  ..............            0.04  ..............            0.01             0.3               2
Killer whale....................................................  ..............             0.4  ..............            0.08  ..............            0.02             0.5              10
Beluga (Trading Bay)............................................  ..............             0.5  ..............             0.2  ..............            0.05             0.8              11
Beluga (NCI)....................................................  ..............             4.8  ..............              NA  ..............              NA             4.8  ..............

[[Page 51122]]

 
Dall's porpoise.................................................  ..............             0.1  ..............            0.01  ..............           0.005             0.1               6
Harbor porpoise.................................................  ..............             2.8  ..............             0.3  ..............             0.1             3.2              12
Pacific white-sided dolphin.....................................  ..............           0.000  ..............           0.000  ..............           0.000           0.000               3
Harbor seal.....................................................  ..............           152.6  ..............            15.2  ..............             7.6           175.4             176
Steller sea lion................................................  ..............             4.8  ..............             0.5  ..............             0.2             5.5               6
California sea lion.............................................  ..............           0.000  ..............           0.000  ..............           0.000           0.000               2
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ This zone assumes a 35 km towing distance (the farthest potential distance that Furie may need to tow the rig).
\2\ Level B harassment zone area x density x 2 (towing at beginning and end of season), with the exception of Cook Inlet beluga whale. For Cook Inlet beluga whale, Furie used the Trading Bay
  density for the initial rig tow since the density is predicted to be higher there than in the North Cook Inlet Lease Unit (located offshore in middle Cook Inlet), and Furie may tug the rig
  though that area. Furie used the NCI density to estimate take for the end of season tow. NMFS concurs and has used these two separate densities in its analysis.
\3\ Level B harassment zone (63.1 km\2\) x species density (table 11), x number of potential positioning attempts (2).
\4\ Level B harassment zone (7.89 km\2\) x species density (table 11) x estimated number of days that conductor pile installation would occur (4).

    Explanations for species for which take proposed for authorization 
is greater than calculated take are included below.
    Several recent surveys and monitoring programs have documented 
groups of humpback whales ranging up to 14 whales in size. During the 
annual survey, Shelden et al. (2022) recorded a group of three humpback 
whales west of Kachemak Bay in June of 2022. Past annual aerial surveys 
have documented groups up to 12 in number (Shelden et al. 2013, 2015, 
2016, 2019). During Hilcorp's lower Cook Inlet seismic survey, group 
size ranged from 1 to 14 (Fairweather Science 2020). During monitoring 
of the Harvest Alaska CIPL project (the closest to Furie's Action 
Area), two sightings of three humpbacks were reported. During 
construction of the JRP in 2015, a group of 6 to 10 unidentified 
whales, thought to be either gray whales or humpbacks, was observed 
approximately 15 km northeast of the platform (Jacobs 2015). There were 
two sightings of three humpback whales observed near Ladd Landing north 
of the Forelands during the Harvest Alaska CIPL project (Sitkiewicz et 
al. 2018). Furie requested, and NMFS is proposing to authorize, three 
takes of humpback whale by Level B harassment in Year 1. This estimate 
accounts for the potential of take of a group of two animals and a 
solitary animal.
    Groups of up to three minke whales have been recorded in recent 
years, including one group of three southeast of Kalgin Island (Lomac-
MacNair et al. 2014). Other recent surveys in Cook Inlet typically have 
documented minkes traveling alone (Shelden et al. 2013, 2015, 2017; 
Kendall et al. 2015, as cited in Weston and SLR 2022; Fairweather 
Science 2020). As the occurrence of minke whales is expected to be less 
in middle Cook Inlet than lower Cook Inlet and considering the observed 
group sizes, Furie requested, and NMFS is proposing to authorize, three 
takes of minke whale by Level B harassment in Year 1 to account for the 
potential of take of a group of three minke whales.
    During Apache's 2012 seismic program, nine gray whales were 
observed in June and July (Lomac-MacNair et al. 2013). During Apache's 
seismic program in 2014, one gray whale was observed (Lomac-MacNair et 
al. 2014). During construction of the JRP in 2015, 1 gray whale was 
documented approximately 5 km from the platform, and a group of 6 to 10 
unidentified whales, thought to be either gray whales or humpbacks, was 
observed approximately 15 km northeast of the platform (Jacobs 2015). 
During SAExploration's seismic survey in 2015, the 2018 CIPL project, 
and Hilcorp's 2019 seismic survey, no gray whales were observed 
(Kendall et al. 2015; Sitkiewicz et al. 2018; Fairweather Science, 
2020). None were observed during the 2018 CIPL project in middle Cook 
Inlet (Sitkiewicz et al. 2018). In 2020 and 2021, one gray whale was 
reported in each season at the POA (61N 2021, 2022a). The documented 
occasional presence of gray whales near and north of the project area 
suggests that gray whale density may be seasonally higher than the 
relatively low density suggested by the aerial surveys. Considering the 
project area is in middle Cook Inlet where sightings of gray whales are 
less common, Furie requested, and NMFS is proposing to authorize, take 
of three gray whales in Year 1.
    During seismic surveys conducted in 2019 by Hilcorp in the lower 
Cook Inlet, fin whales were recorded in groups ranging in size from one 
to 15 individuals (Fairweather, 2020). During the NMFS aerial surveys 
in Cook Inlet from 2000 to 2018, 10 sightings of 26 estimated 
individual fin whales in lower Cook Inlet were observed (Shelden et al. 
2013, 2015, 2016, 2019). Furie requested, and NMFS is proposing to 
authorize, take of one group of two fin whales (the lower end of the 
range of common group sizes) in Year 1.
    Killer whales are typically sighted in pods of a few animals to 20 
or more (NOAA, 2022a). During seismic surveys conducted in 2019 by 
Hilcorp in the lower Cook Inlet, 21 killer whales were observed, either 
as single individuals or in groups ranging in size from 2 to 5 
individuals (Fairweather, 2020). Furie requested 10 takes by Level B 
harassment in Year 1 to account for 2 groups of 5 animals. NMFS concurs 
and proposes to authorize 10 takes by Level B harassment of killer 
whale.
    The 2018 MML aerial survey (Shelden and Wade 2019) estimated a 
median group size of approximately 11 beluga whales, although group 
sizes were highly variable (2 to 147 whales) as was the case in 
previous survey years (Boyd et al. 2019). Over 3 seasons of monitoring 
at the POA, 61N reported groups of up to 53 belugas, with a median 
group size of 3 and a mean group size of 4.4 (61N 2021, 2022a, 2022b, 
and 2022c). Additionally, vessel-based surveys in 2019 observed beluga 
whale groups in the Susitna River Delta (roughly 24 km [15 miles] north 
of the Tyonek Platform) that ranged from 5 to 200 animals (McGuire et 
al. 2022). The very large groups seen in the Susitna River Delta are 
not expected in Trading Bay or offshore areas near the JRP or the 
towing route for the Enterprise 151. However, smaller groups (i.e., 
around the median group size) could be traveling through to access the 
Susitna River Delta and other nearby coastal locations, particularly in 
the shoulder seasons when belugas are more likely to occur in middle 
Cook Inlet. Few if any takes of beluga whale are anticipated

[[Page 51123]]

during impact installation of the conductor piles. Therefore, Furie 
requested, and NMFS is proposing to authorize, 11 takes by Level B 
harassment of beluga whale in Year 1.
    Dall's porpoises typically occur in groups averaging between 2 and 
12 individuals (NOAA, 2024b). During seismic surveys conducted in 2019 
by Hilcorp in the lower Cook Inlet, Dall's porpoises were observed in 
groups ranging in size from two to seven individuals (Fairweather, 
2020). The 2012 Apache survey recorded two groups of three individual 
Dall's porpoises (Lomac-MacNair, 2014). Because occurrence of Dall's 
porpoise is anticipated to be less in middle Cook Inlet than lower Cook 
Inlet, the smaller end of documented group sizes (three individuals) is 
used. NMFS is proposing to authorize six takes (two groups of three 
animals) by Level B harassment of Dall's porpoise in Year 1.
    Shelden et al. (2014) compiled historical sightings of harbor 
porpoises from lower to upper Cook Inlet that spanned from a few 
animals to 92 individuals. The 2018 CIPL project that occurred just 
north of the Action Area in Cook Inlet reported 29 sightings of 44 
individuals (Sitkiewicz et al. 2018). While the duration of days that 
the tugs are towing a jack-up rig will be less than the CIPL project, 
given the increase in sightings of harbor porpoise in recent years, the 
sighting of harbor porpoise during Hilcorp's rig move in June 2022, and 
the inability to shut down the tugs, Furie requested, and NMFS is 
proposing to authorize, 12 takes by Level B harassment of harbor 
porpoise. This accounts for two potential groups of six animals.
    Calculated take of Pacific white-sided dolphin was zero because the 
estimated density is zero. However, in 2014, during Apache's seismic 
survey program, three Pacific white-sided dolphins were reported 
(Lomac-MacNair et al. 2014). They are considered rare in most of Cook 
Inlet, including in the lower entrance, but their presence was 
documented in Iniskin Bay and mid-inlet through passive acoustic 
recorders in 2019 (Castellote et al. 2020). Furie conservatively 
requested three takes based on the potential that a group similar in 
size to that encountered in 2014 could occur within the Level B 
harassment zone during project activities. NMFS concurs, and has 
conservatively proposed to authorize three takes of Pacific white-sided 
dolphin by Level B harassment.
    Calculated take of California sea lions was zero because the 
assumed density in Cook Inlet is zero. Any potential sightings would 
likely be of lone out of habitat individuals. Two solitary individuals 
were seen during the 2012 Apache seismic survey in Cook Inlet (Lomac-
MacNair et al. 2013). Furie requested two takes based on the potential 
that two lone animals could be sighted over a year of work, as was seen 
during Apache's year of work. NMFS concurs, and has conservatively 
proposed to authorize two takes of California sea lion by Level B 
harassment.
Year 2 IHA
    Given that Furie intends to conduct the same activities in Year 2 
as in Year 1, take by Level A harassment and Level B harassment 
proposed for authorization for Year 2 is the same as that proposed for 
authorization for Year 1 (table 12).

                                      Table 13--Take Proposed for Authorization as a Percentage of Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                      Year 1                          Year 2
                                                                                         ---------------------------------------------------------------
                                                                             Abundance      Total take       Take as a      Total take       Take as a
                Species                               Stock                   (Nbest)      (Level A and    percentage of   (Level A and    percentage of
                                                                                              Level B          stock          Level B          stock
                                                                                            harassment)      abundance      harassment)      abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale.........................  Hawaii (Hawaii DPS)............          11,278               3              <1               3              <1
                                         Mexico-North Pacific (Mexico            \1\ N/A  ..............             N/A  ..............             N/A
                                          DPS).
                                         Western North Pacific..........           1,084  ..............              <1  ..............              <1
Minke whale............................  Alaska.........................         \2\ N/A               3             N/A               3             N/A
Gray whale.............................  Eastern Pacific................          26,960               3              <1               3              <1
Fin whale..............................  Northeast Pacific..............         \3\ UND               2             N/A               2             N/A
Killer whale...........................  Eastern North Pacific Alaska              1,920              10              <1              10              <1
                                          Resident.
                                         Eastern North Pacific Gulf of               587  ..............              <1  ..............              <1
                                          Alaska, Aleutian Islands, and
                                          Bering Sea Transient.
Beluga.................................  Cook Inlet.....................         \4\ 279              11             3.9              11             3.9
Dall's porpoise........................  Alaska.........................         \5\ UND               6             N/A               6             N/A
Harbor porpoise........................  Gulf of Alaska.................          31,046              12              <1              12              <1
Pacific white-sided dolphin............  North Pacific..................          26,880               3              <1               3              <1
Harbor seal............................  Cook Inlet/Shelikof............          28,411             179              <1             179              <1
Steller sea lion.......................  Western U.S....................      \6\ 49,932               6              <1               6              <1
California sea lion....................  U.S............................         257,606               2              <1               2              <1
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Abundance estimates are based upon data collected more than 8 years ago and, therefore, current estimates are considered unknown.
\2\ Reliable population estimates are not available for this stock. Please see Friday et al. (2013) and Zerbini et al (2006) for additional information
  on numbers of minke whales in Alaska.
\3\ The best available abundance estimate for this stock is not considered representative of the entire stock as surveys were limited to a small portion
  of the stock's range.
\4\ On June 15, 2023, NMFS released an updated abundance estimate for endangered Cook Inlet beluga whales in Alaska (Goetz et al. 2023). Data collected
  during NOAA Fisheries' 2022 aerial survey suggest that the whale population is stable or may be increasing slightly. Scientists estimated that the
  population size is between 290 and 386, with a median best estimate of 331. In accordance with the MMPA, this population estimate will be incorporated
  into the Cook Inlet beluga whale SAR, which will be reviewed by an independent panel of experts, the Alaska Scientific Review Group. After this
  review, the SAR will be made available as a draft for public review before being finalized. When the number of instances of takes is compared to this
  median abundance, the percent of the stock proposed for authorization is 3.3 percent.
\5\ The best available abundance estimate is likely an underestimate for the entire stock because it is based upon a survey that covered only a small
  portion of the stock's range.
\6\ Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys.

Proposed Mitigation

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

[[Page 51124]]

for taking for certain subsistence uses. NMFS regulations require 
applicants for incidental take authorizations to include information 
about the availability and feasibility (economic and technological) of 
equipment, methods, and manner of conducting the activity or other 
means of effecting the least practicable adverse impact upon the 
affected species or stocks, and their habitat (50 CFR 216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, NMFS 
considers two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat, as 
well as subsistence uses. This considers the nature of the potential 
adverse impact being mitigated (likelihood, scope, range). It further 
considers the likelihood that the measure will be effective if 
implemented (probability of accomplishing the mitigating result if 
implemented as planned), the likelihood of effective implementation 
(probability implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost and impact on 
operations.
    In addition to the measures described in detail below, Furie will 
conduct briefings between conductor pipe installation supervisors, 
vessel captains and crew, and the marine mammal monitoring team before 
the start of all in-water work and when new personnel join the work to 
explain responsibilities, communication procedures, marine mammal 
monitoring protocol, and operational procedures.

Mitigation for Rig Tugging/Positioning

    NMFS anticipates that there is a discountable potential for marine 
mammals to incur PTS from the tugging and positioning, as source levels 
are relatively low, non-impulsive, and animals would have to remain at 
very close distances for multiple hours to accumulate acoustic energy 
at levels that could damage hearing. Therefore, we do not believe there 
is reasonable potential for Level A harassment from rig tugging or 
positioning. However, Furie will implement a number of mitigation 
measures designed to reduce the potential for and severity of Level B 
harassment, and minimize the acoustic footprint of the project.
Protected Species Observers
    Furie will station PSOs at the highest possible vantage point on 
either the rig or on one of the tugs.
Pre-Clearance and Post-Activity Monitoring
    The tugs towing a rig are not able to shut down while transiting or 
positioning the rig. Furie will maneuver the tugs towing the rig such 
that they maintain a consistent speed (approximately 4 knots or less[7 
km/hr]) and avoid multiple changes of speed and direction to make the 
course of the vessels as predictable as possible to marine mammals in 
the surrounding environment, characteristics that are expected to be 
associated with a lower likelihood of disturbance.
    During tugging activities, Furie would implement a clearance zone 
of 1,500 m around the rig for all marine mammals other than Cook Inlet 
beluga whales. This proposed clearance zone was determined to be 
appropriate as it is approximately twice as large as largest Level A 
harassment zone (table 10) and is a reasonable distance within which 
cryptic species (e.g., porpoises, pinnipeds) could be observed. For 
Cook Inlet beluga whales, Furie would implement a clearance zone that 
extends as far as PSOs can feasibly observe for Cook Inlet beluga 
whales. Prior to commencing new activities during daylight hours or if 
there is a 30-minute lapse in operational activities, the PSOs will 
monitor the clearance zone for marine mammals for 30 minutes (i.e., 
pre-clearance monitoring). (Note, transitioning from towing to 
positioning without shutting down would not be considered commencing a 
new operational activity.) If no marine mammals are observed within the 
relevant clearance zone during this pre-clearance monitoring period, 
tugging activities may commence. If a marine mammal(s) is observed 
within the relevant clearance zone during the pre-clearance monitoring 
period, tugging activities would be delayed, unless the delay 
interferes with the safety of working conditions. Operations would not 
commence until the PSO(s) observe that: (1) the non-Cook Inlet beluga 
whale animal(s) is outside of and on a path away from the clearance 
zone; (2) the Cook Inlet beluga whale is no longer detected at any 
range; or (3) for non-ESA-listed species, 15 minutes have elapsed 
without observing the marine mammal, or for ESA-listed species, 30 
minutes have elapsed without observing the marine mammal. Once the PSOs 
have determined one of those conditions are met, operations may 
commence. PSOs would also conduct monitoring for marine mammals through 
30 minutes post-completion of any tugging activity each day, and after 
each stoppage of 30 minutes or greater.
    During nighttime hours or low/no-light conditions, night-vision 
devices (NVDs) shown to be effective at detecting marine mammals in 
low-light conditions (e.g., Portable Visual Search-7 model, or similar) 
would be provided to PSOs to aid in their monitoring of marine mammals. 
Every effort would be made to observe that the relevant clearance zone 
is free of marine mammals by using night-vision devices and or the 
naked eye, however it may not always be possible to see and clear the 
entire clearance zones prior to nighttime transport. Prior to 
commencing new operational activities during nighttime hours, or if 
there is a 30-minute lapse in operational activities in low/no-light 
conditions, the PSOs must observe the extent visible while using night 
vision devices for 30 minutes (i.e., pre-clearance monitoring). If no 
marine mammals are observed during this pre-clearance period, tugging 
activities may commence. If a marine mammal(s) is observed within the 
pre-clearance monitoring period, tugging activities would be delayed, 
unless the delay interferes with the safety of working conditions. 
Operations would not commence until the PSO(s) observe that: (1) the 
animal(s) is outside of the observable area; or (2) for non-ESA-listed 
species, 15 minutes have elapsed without observing the marine mammal, 
or for ESA-listed species, 30 minutes have elapsed without observing 
the marine mammal Once the PSOs have determined one of those conditions 
are met, operations may commence.
    PSOs must scan the waters for at least 30 minutes after tugging and 
positioning activities have been completed each day, and after each 
stoppage of 30 minutes or greater.
    Should a marine mammal be observed during towing or positioning of 
the rig, the PSOs will monitor and carefully record any reactions 
observed until the towing or positioning has concluded. PSOs will also 
collect behavioral information on marine mammals sighted during 
monitoring efforts.
Nighttime Work
    Furie will conduct tug towing operations with the tide, resulting 
in a low power output from the tugs towing the rig, unless human safety 
or equipment integrity is at risk. Due to the nature of tidal cycles in 
Cook Inlet, it is possible the most favorable tide for the towing 
operation will occur during

[[Page 51125]]

nighttime hours. Furie will only operate the tug towing activities at 
night if necessary to accommodate a favorable tide. Prior to commencing 
operational activities during nighttime hours or low/no-light 
conditions, Furie must implement the pre-clearance measures described 
above.
Susitna Delta
    The Tyonek platform is within the Susitna Delta Exclusion Zone 
identified in Hilcorp's IHAs (87 FR 62364, October 14, 2022). If 
Hilcorp does conduct work at the Tyonek platform, it would maintain 
operatorship and control of the Enterprise 151 until the tow is 
underway with lines taut and the Enterprise 151 is under tug power. 
Once the tow is underway, Furie representatives will take over 
operatorship of the Enterprise 151.
    Out of concern for potential disturbance to Cook Inlet beluga 
whales in sensitive and essential habitat, Furie would maintain a 
distance of 2.4 km from the mean lower-low water (MLLW) line of the 
Susitna River Delta (Beluga River to the Little Susitna River) between 
April 15 and November 15. The dates of applicability of this exclusion 
zone have been expanded based on new available science, including 
visual surveys and acoustic studies, which indicate that substantial 
numbers of Cook Inlet beluga whales continue to occur in the Susitna 
Delta area through at least mid-November (M. Castellote, pers. comm., 
T. McGuire, pers. comm.). Of note, Furie does not expect to operate in 
this area, but if it does, this measure would apply.

Mitigation for Conductor Pile Installation

    NMFS proposes that Furie must implement the following measures for 
impact driving of conductor piles.
Shutdown Zones
    The purpose of a shutdown zone is generally to define an area 
within which shutdown of the activity would occur upon sighting of a 
marine mammal (or in anticipation of an animal entering the defined 
area). Construction supervisors and crews, PSOs, and relevant Furie 
staff must avoid direct physical interaction with marine mammals during 
construction activity. If a marine mammal comes within 10 m of such 
activity, operations must cease and vessels must reduce speed to the 
minimum level required to maintain steerage and safe working 
conditions, as necessary to avoid direct physical interaction. Further, 
Furie must implement shutdown zones as described in table 14. Furie 
states that if a shutdown or delay occurs, impact installation of the 
conductor pipe will not commence or resume until the animal has 
voluntarily left and been visually confirmed to be 100 m beyond the 
shutdown zone and on a trajectory away from the zone, or 30 minutes 
have passed without subsequent detections. If Cook Inlet beluga whales 
are observed within or approaching the Level B harassment zone for 
conductor pipe installation, impact installation of the conductor pipe 
will be delayed or halted until the beluga(s) have voluntarily left and 
been visually confirmed to be 100 m beyond the Level B harassment zone 
and on a trajectory away from the zone, or 30 minutes have passed 
without subsequent detections.

        Table 14--Shutdown Zones for Conductor Pipe Pile Driving
------------------------------------------------------------------------
                                                           Shutdown zone
                      Hearing group                             (m)
------------------------------------------------------------------------
Low-frequency Cetaceans.................................           2,000
Mid-frequency Cetaceans.................................             110
High-frequency Cetaceans................................             400
Phocids.................................................             400
Otariids................................................             120
------------------------------------------------------------------------

Protected Species Observers
    Furie will establish a monitoring location on the JRP at the 
highest possible vantage point to monitor to the maximum extent 
possible in all directions. Monitoring is described in more detail in 
the Proposed Monitoring and Reporting section, below.
Pre- and Post-Activity Monitoring
    Monitoring must take place from 30 minutes prior to initiation of 
pile driving activity (i.e., pre-start clearance monitoring) through 30 
minutes post-completion of pile driving activity. Pre-start clearance 
monitoring must be conducted during periods of visibility sufficient 
for the lead PSO to determine that the shutdown zones indicated in 
table 14 are clear of marine mammals. Pile driving may commence 
following 30 minutes of observation when the determination is made that 
the shutdown zones are clear of marine mammals. If a marine mammal is 
observed entering or within the shutdown zones, pile driving activity 
must be delayed or halted. If pile driving is delayed or halted due to 
the presence of a marine mammal, the activity may not commence or 
resume until either the animal has voluntarily exited and been visually 
confirmed beyond the shutdown zone for 15 minutes (for non-ESA-listed 
species) or 30 minutes (for ESA-listed species) have passed without re-
detection of the animal. With the exception of Cook Inlet beluga 
whales, if a marine mammal for which take by Level B harassment is 
authorized is present in the Level B harassment zone but beyond the 
relevant shutdown zone, activities may begin and Level B harassment 
take would be recorded.
Monitoring for Level A and Level B Harassment
    PSOs would monitor the shutdown zones and beyond to the extent that 
PSOs can see. Monitoring beyond the shutdown zones enables observers to 
be aware of and communicate the presence of marine mammals in the 
project areas outside the shutdown zones and thus prepare for a 
potential cessation of activity should the animal enter the shutdown 
zone.
Soft Start
    Soft-start procedures are used to provide additional protection to 
marine mammals by providing warning and/or giving marine mammals a 
chance to leave the area prior to the hammer operating at full 
capacity. For impact pile driving, soft start requires contractors to 
provide an initial set of three strikes at reduced energy, followed by 
a 30-second waiting period, then two subsequent reduced-energy strike 
sets. A soft start must be implemented at the start of each day's 
impact pile driving and at any time following cessation of impact pile 
driving for a period of 30 minutes or longer.

Mitigation for Helicopter Activities

    Helicopters must transit at an altitude of 1,500 ft (457 m) or 
higher, to the extent practicable, while adhering to Federal Aviation 
Administration flight rules (e.g., avoidance of cloud ceiling, etc.), 
excluding takeoffs and landing. If flights must occur at altitudes less 
than 1,500 ft due to environmental conditions, aircraft must make 
course adjustments, as needed, to maintain at least a 1,500- foot 
separation from all observed marine mammals. Helicopters must not hover 
or circle above marine mammals. A minimum transit altitude is expected 
to reduce the potential for disturbance to marine mammals from 
transiting aircraft.
    Based on our evaluation of Furie's proposed measures, as well as 
other measures considered by NMFS (i.e., the extended clearance zone 
for beluga whales), for both IHAs, NMFS has preliminarily determined 
that the proposed mitigation measures provide the means of effecting 
the least practicable impact on the affected species or stocks and 
their habitat,

[[Page 51126]]

paying particular attention to rookeries, mating grounds, and areas of 
similar significance, and on the availability of such species or stock 
for subsistence uses.

Proposed Monitoring and Reporting

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

Monitoring

    Furie would abide by all monitoring and reporting measures 
contained within the IHA, if issued, and their Marine Mammal Monitoring 
and Mitigation Plan (see Appendix B of Furie's application). A summary 
of those measures and additional requirements proposed by NMFS is 
provided below.
    A minimum of two NMFS-approved PSOs will be on-watch during all 
activities wherein the rig is attached to the tugs for the duration of 
the project. PSOs will be stationed aboard a tug or the rig during tug 
towing and positioning and may use a combination of equipment to 
perform marine mammal observations and to verify the required 
monitoring distance from the project site, including 7 by 50 binoculars 
and NMFS approved NVDs for low light and nighttime operations. A 
minimum of two NMFS-approved PSOs will be stationed on the JRP at the 
highest possible vantage point to monitor to the maximum extent 
possible in all directions during pile driving. PSOs would be 
independent of the activity contractor (for example, employed by a 
subcontractor) and have no other assigned tasks during monitoring 
periods. At least one PSO would have prior experience performing the 
duties of a PSO during an activity pursuant to a NMFS-issued Incidental 
Take Authorization or Letter of Concurrence. Other PSOs may substitute 
other relevant experience (including relevant Alaska Native traditional 
knowledge), education (degree in biological science or related field), 
or training for prior experience performing the duties of a PSO. Where 
a team of three or more PSOs is required, a lead observer or monitoring 
coordinator must be designated. The lead observer must have prior 
experience performing the duties of a PSO during an activity pursuant 
to a NMFS-issued incidental take authorization.
    PSOs would also have the following additional qualifications:
     PSOs must be able to conduct field observations and 
collect data according to assigned protocols;
     PSOs must have experience or training in the field 
identification of marine mammals, including the identification of 
behaviors;
     PSOs must have sufficient training, orientation, or 
experience with the tugging operation to provide for personal safety 
during observations;
     PSOs must have sufficient writing skills to record 
required information including but not limited to the number and 
species of marine mammals observed; dates and times when in-water 
tugging activities were conducted; dates, times, and reason for 
implementation of mitigation (or why mitigation was not implemented 
when required); and marine mammal behavior; and
     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.

Reporting

    Furie would submit interim monthly reports for all months in which 
tugs towing, holding, or positioning the rig occurs. Monthly reports 
would include a summary of marine mammal species and behavioral 
observations, delays, and tugging activities completed. They also must 
include an assessment of the amount of tugging remaining to be 
completed, in addition to the number of Cook Inlet beluga whales 
observed within estimated harassment zones to date.
    A draft marine mammal monitoring report would be submitted to NMFS 
within 90 days after the completion of the tug towing rig activities 
for the year. It will include an overall description of work completed, 
a narrative regarding marine mammal sightings, and associated marine 
mammal observation data sheets in an electronic format. Specifically, 
the report must include the following information:
     Date and time that monitored activity begins or ends;
     Activities occurring during each observation period, 
including (a) the type of activity, (b) the total duration of each type 
of activity, (c) the number of attempts required for positioning, (d) 
when nighttime operations were required (e) whether towing against the 
tide was required, (f) the number and type of piles that were driven 
and the method (e.g., impact, vibratory, down-the-hole), and (g) total 
number of strikes for each pile.
     PSO locations during marine mammal monitoring;
     Environmental conditions during monitoring periods (at the 
beginning and end of the PSO shift and whenever conditions change 
significantly), including Beaufort sea state, tidal state, and any 
other relevant weather conditions, including cloud cover, fog, sun 
glare, overall visibility to the horizon, and estimated observable 
distance;
     Upon observation of a marine mammal, (a) name of PSO who 
sighted the animal(s) and PSO location and

[[Page 51127]]

activity at time of sighting, (b) time of sighting, (c) identification 
of the animal(s) (e.g., genus/species, lowest possible taxonomic level, 
or unidentified), PSO confidence in identification, and the composition 
of the group if there is a mix of species, (d) distance and location of 
each observed marine mammal relative to the tugs or pile being driven 
for each sighting, (e) estimated number of animals (min/max/best 
estimate), (f) estimated number of animals by cohort (adults, 
juveniles, neonates, group composition, etc.), (g) animal's closest 
point of approach and estimated time spent within the harassment zone, 
(h) description of any marine mammal behavioral observations (e.g., 
observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted from the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones, by species; and
     Detailed information about implementation of any 
mitigation (e.g., shutdowns and delays), a description of specific 
actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    If no comments are received from NMFS within 30 days, the draft 
summary report will constitute the final report. If NMFS submits 
comments, Furie will submit a final summary report addressing NMFS 
comments within 30 days after receipt of comments.
    In the event that personnel involved in Furie's activities discover 
an injured or dead marine mammal, Furie must report the incident to the 
Office of Protected Resources (OPR), NMFS 
([email protected] and [email protected]) and to the 
Alaska regional stranding network as soon as feasible. If the death or 
injury was clearly caused by the specified activity, Furie must 
immediately cease the activities until NMFS OPR is able to review the 
circumstances of the incident and determine what, if any, additional 
measures are appropriate to ensure compliance with the IHAs. The Holder 
must not resume their activities until notified by NMFS.
    The report must include the following information:
    (i) Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
    (ii) Species identification (if known) or description of the 
animal(s) involved;
    (iii) Condition of the animal(s) (including carcass condition if 
the animal is dead);
    (iv) Observed behaviors of the animal(s), if alive;
    (v) If available, photographs or video footage of the animal(s); 
and
    (vi) General circumstances under which the animal was discovered.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' through harassment, NMFS considers other factors, such as the 
likely nature of any impacts or responses (e.g., intensity, duration), 
the context of any impacts or responses (e.g., critical reproductive 
time or location, foraging impacts affecting energetics), as well as 
effects on habitat, and the likely effectiveness of the mitigation. We 
also assess the number, intensity, and context of estimated takes by 
evaluating this information relative to population status. Consistent 
with the 1989 preamble for NMFS' implementing regulations (54 FR 40338, 
September 29, 1989), the impacts from other past and ongoing 
anthropogenic activities are incorporated into this analysis via their 
impacts on the baseline (e.g., as reflected in the regulatory status of 
the species, population size and growth rate where known, ongoing 
sources of human-caused mortality, or ambient noise levels).
    To avoid repetition, the majority of our analysis applies to all 
the species listed in table 13, except for Cook Inlet beluga whale and 
harbor seal, given that many of the anticipated effects of this project 
on different marine mammal stocks are expected to be relatively similar 
in nature. For Cook Inlet beluga whales and harbor seals, there are 
meaningful differences in anticipated individual responses to 
activities, impact of expected take on the population, or impacts on 
habitat; therefore, we provide a separate independent detailed analysis 
for Cook Inlet beluga whales and harbor seals following the analysis 
for other species for which we propose take authorization.
    NMFS has identified several key factors which may be employed to 
assess the level of analysis necessary to conclude whether potential 
impacts associated with a specified activity should be considered 
negligible. These include (but are not limited to) the type and 
magnitude of taking, the amount and importance of the available habitat 
for the species or stock that is affected, the duration of the 
anticipated effect on the individuals, and the status of the species or 
stock. The potential effects of the specified activity on humpback 
whales, minke whales, gray whales, fin whales, killer whales, Dall's 
porpoises, harbor porpoises, Pacific white-sided dolphins, Steller sea 
lions, and California sea lions are discussed below. These factors also 
apply to Cook Inlet beluga whales and harbor seals; however, additional 
analysis for Cook Inlet beluga whales and harbor seals is provided in a 
separate subsection below.
    Furie's tugging activities associated with this project, as 
outlined previously, have the potential to harass marine mammals. 
Specifically, the specified activities may result in take, in the form 
of Level B harassment, from underwater sounds generated by tugs towing, 
holding, and positioning a rig. Potential takes could occur if marine 
mammals are present in zones ensonified above the thresholds for Level 
B harassment, identified above, while activities are underway.
    Furie's planned activities and associated impacts would occur 
within a limited area of the affected species' or stocks' ranges over a 
total of 4 days each year for tugging, and 2 days for pile driving. The 
intensity and duration of take by Level B harassment would be minimized 
through use of mitigation measures described herein. Further the amount 
of take proposed to be authorized is small when compared to stock 
abundance (table 13). In addition, NMFS does not anticipate that 
serious injury or mortality would occur as a result of Furie's planned 
activity given the nature of the activity, even in the absence of 
required mitigation.
    Exposures to elevated sound levels produced during tugging and pile 
driving activities may cause behavioral disturbance of some individuals 
within the vicinity of the sound source. Behavioral responses of marine 
mammals to Furie's tugging activities are expected to be mild, short 
term, and temporary. Effects on individuals that are taken by Level B 
harassment, as enumerated in the Estimated Take

[[Page 51128]]

section, on the basis of reports in the literature as well as 
monitoring from other similar activities conducted by Furie (Horsley 
and Larson, 2023), would likely be limited to behavioral response such 
as increased swimming speeds, changing in directions of travel and 
diving and surfacing behaviors, increased respiration rates, or 
interrupted foraging (if such activity were occurring) (Ridgway et al. 
1997; Nowacek et al. 2007; Thorson and Reyff, 2006; Kendall and Cornick 
2015; Goldbogen et al. 2013b; Blair et al. 2016; Wisniewska et al. 
2018; Piwetz et al. 2021). Marine mammals within the Level B harassment 
zones may not present any visual cues they are disturbed by activities, 
or they may become alert, avoid the area, leave the area, or have other 
mild responses that are not observable such as increased stress levels 
(e.g., Rolland et al. 2012; Lusseau, 2005; Bejder et al. 2006; Rako et 
al. 2013; Pirotta et al. 2015b; P[eacute]rez-Jorge et al. 2016). They 
may also exhibit increased vocalization rates (e.g., Dahlheim 1987; 
Dahlheim and Castellote 2016), louder vocalizations (e.g., Frankel and 
Gabriele 2017; Fournet et al. 2018), alterations in the spectral 
features of vocalizations (e.g., Castellote et al. 2012), or a 
cessation of communication signals (e.g., Tsujii et al. 2018). However, 
as described in the Potential Effects of Specified Activities on Marine 
Mammals and Their Habitat section, marine mammals observed near Furie's 
tugging activities have shown little to no observable reactions to 
tugging activities (Horsley and Larson 2023).
    Tugs pulling, holding, and positioning a rig are slow-moving as 
compared to typical recreational and commercial vessel traffic. 
Assuming an animal was stationary, exposure to sound above the Level B 
harassment threshold from the moving tug configuration (which comprises 
most of the tug activity being considered) would be on the order of 
minutes in any particular location. The slow, predictable, and 
generally straight path of this activity is expected to further lower 
the likelihood of more than low-level responses to the sound. Also, 
this slow transit along a predictable path is planned in an area of 
routine vessel traffic where many large vessels move in slow straight-
line paths, and some individuals are expected to be habituated to these 
sorts of sounds. While it is possible that animals may swim around the 
project area, avoiding closer approaches to the boats, we do not expect 
them to abandon any intended path. Further, most animals present in the 
region would likely be transiting through the area; therefore, any 
potential exposure is expected to be brief. Based on the 
characteristics of the sound source and the other activities regularly 
encountered in the area, it is unlikely Furie's planned tugging 
activities would be of a duration or intensity expected to result in 
impacts on reproduction or survival.
    Effects on individuals that are taken by Level B harassment during 
pile driving, on the basis of reports in the literature as well as 
monitoring from other similar activities, would likely be limited to 
reactions such as increased swimming speeds, increased surfacing time, 
or interrupted foraging (if such activity were occurring; e.g., Thorson 
and Reyff 2006; HDR, Inc. 2012; Lerma 2014; ABR 2016). Most likely, 
individuals would simply move away from the sound source and be 
temporarily displaced from the areas of pile driving and removal. If 
sound produced by project activities is sufficiently disturbing, 
animals are likely to simply avoid the area while the activity is 
occurring, particularly as the project is expected to occur over a 
maximum of just 2 days of in-water pile driving during each year.
    Most of the species present in the region would only be present 
temporarily based on seasonal patterns or during transit between other 
habitats. These temporarily present species would be exposed to even 
smaller periods of noise-generating activity, further decreasing the 
impacts. Most likely, individual animals would simply move away from 
the sound source and be temporarily displaced from the area. Takes may 
also occur during important feeding times. The project area though 
represents a small portion of available foraging habitat and impacts on 
marine mammal feeding for all species should be minimal.
    We anticipate that any potential reactions and behavioral changes 
are expected to subside quickly when the exposures cease and, 
therefore, we do not expect long-term adverse consequences from Furie's 
proposed activities for individuals of any species other than harbor 
seal (for which take by Level A harassment is proposed for 
authorization, discussed further below). The intensity of Level B 
harassment events would be minimized through use of mitigation measures 
described herein. Furie would use PSOs to monitor for marine mammals 
before commencing any tugging or construction activities, which would 
minimize the potential for marine mammals to be present within Level B 
harassment zones when tugs are under load or within the shutdown zones 
at the commencement of construction. Further, given the absence of any 
major rookeries, haulouts, or areas of known biological significance 
for marine mammals (e.g., foraging hot spots) within the estimated 
harassment zones (other than critical habitat and a BIA for Cook Inlet 
beluga whales as described below), we preliminarily conclude that any 
takes by Level B harassment would have an inconsequential short-term 
effect on individuals and would not result in population-level impacts.
    Theoretically, repeated, sequential exposure to elevated noise from 
tugging activities over a long duration could result in more severe 
impacts to individuals that could affect a population (via sustained or 
repeated disruption of important behaviors such as feeding, resting, 
traveling, and socializing; Southall et al. 2007). Alternatively, 
marine mammals exposed to repetitious sounds may become habituated, 
desensitized, or tolerant after initial exposure to these sounds 
(reviewed by Richardson et al. 1995; Southall et al. 2007). Cook Inlet 
is a regional hub of marine transportation, and is used by various 
classes of vessels, including containerships, bulk cargo freighters, 
tankers, commercial and sport-fishing vessels, and recreational 
vessels. Off-shore vessels, tug vessels, and tour boats represent 86 
percent of the total operating days for vessels in Cook Inlet (BOEM 
2016). Given that marine mammals still frequent and use Cook Inlet 
despite being exposed to anthropogenic sounds such as those produced by 
tug boats and other vessels across many years, population level impacts 
resulting from the additional noise produced by Furie's tugging 
activities are not anticipated.
    Take by Level A harassment of harbor seals is proposed for 
authorization to account for the potential that an animal could enter 
and remain within the area between a Level A harassment zone and the 
shutdown zone during conductor pile installation for a duration long 
enough to be taken by Level A harassment. Any take by Level A 
harassment is expected to arise from, at most, a small degree of PTS 
because animals would need to be exposed to higher levels and/or longer 
duration than are expected to occur here in order to incur any more 
than a small degree of PTS. Additionally, some subset of the 
individuals that are behaviorally harassed could also simultaneously 
incur some small degree of TTS for a short duration of time. Because of 
the small degree anticipated, though, any PTS or TTS potentially 
incurred here is not expected to adversely impact

[[Page 51129]]

individual fitness, let alone annual rates of recruitment or survival.
    Furie's tugging activities are not expected to have significant 
adverse effects on any marine mammal habitat as no temporary or 
physical impacts to habitat are anticipated to result from the 
specified activities. During both tugging and construction, marine 
mammal habitat may be impacted by elevated sound levels, but these 
impacts would be temporary. In addition to being temporary and short in 
overall duration, the acoustic footprint of the proposed activity is 
small relative to the overall distribution of the animals in the area 
and their use of the area. Additionally, the habitat within the 
estimated acoustic footprint is not known to be heavily used by marine 
mammals.
    Impacts to marine mammal prey species are expected to be minor and 
temporary, having, at most, short-term effects on foraging success of 
individual marine mammals, and likely no effect on the populations of 
marine mammals as a whole. Overall, as described above, the area 
anticipated to be impacted by Furie's tugging and construction 
activities is very small compared to the available surrounding habitat, 
and does not include habitat of particular importance. The most likely 
impact to prey would be temporary behavioral avoidance of the immediate 
area. During tugging and construction activities, it is expected that 
some fish would temporarily leave the area of disturbance (e.g., Nakken 
1992; Olsen 1979; Ona and Godo 1990; Ona and Toresen, 1988), thus 
impacting marine mammals' foraging opportunities in a limited portion 
of their foraging range. But, because of the relatively small area of 
the habitat that may be affected, and lack of any foraging habitat of 
particular importance, the impacts to marine mammal habitat are not 
expected to cause significant or long-term negative consequences.
    Finally, Furie will minimize exposure of marine mammals to elevated 
noise levels by implementing mitigation measures for tugging and 
construction activities. For tugging, Furie would delay tugging 
activities if marine mammals are observed during the pre-clearance 
monitoring period. Furie would also implement vessel maneuvering 
measures to reduce the likelihood of disturbing marine mammals during 
any periods when marine mammals may be present near the vessels. 
Lastly, Furie would also reduce the impact of their activity by 
conducting tugging operations with favorable tides whenever feasible. 
For construction, Furie would also delay the start of pile driving 
activities if marine mammals are observed during the pre-clearance 
monitoring period and would implement hearing group-specific shutdown 
zones during the activities. Furie would also implement soft-start 
procedures to provide warning and/or give marine mammals a chance to 
leave the area prior to the hammer operating at full capacity.
    In summary and as described above, the following factors (with 
additional analyses for Cook Inlet beluga whales included below) 
primarily support our preliminary determination that the impacts 
resulting from the activities described for both of these proposed IHAs 
are not expected to adversely affect the species or stocks through 
effects on annual rates of recruitment or survival:
     No serious injury or mortality is anticipated or proposed 
for authorization;
     Take by Level A harassment is not anticipated or proposed 
for authorization for any species except harbor seal;
     Exposure to sounds above harassment thresholds would 
likely be brief given the short duration of the specified activity and 
the transiting behavior of marine mammals in the action area;
     Marine mammal densities are low in the project area; 
therefore, there will not be substantial numbers of marine mammals 
exposed to the noise from the project compared to the affected 
population sizes;
     Take would not occur in places and/or times where take 
would be more likely to accrue to impacts on reproduction or survival, 
such as within ESA-designated or proposed critical habitat, BIAs (other 
than for Cook Inlet beluga whales as described below), or other 
habitats critical to recruitment or survival (e.g., rookery);
     The project area represents a very small portion of the 
available foraging area for all potentially impacted marine mammal 
species;
     Take would only occur within middle Cook Inlet and Trading 
Bay--a limited area of any given species or stock's home range;
     Monitoring reports from previous tugging activities in 
Cook Inlet have documented little to no observable effect on 
individuals of the same species and stocks impacted by the specified 
activities;
     The required mitigation measures (i.e., pre-clearance 
monitoring, vessel maneuver) are expected to be effective in reducing 
the effects of the specified activity by minimizing the numbers of 
marine mammals exposed to sound and the intensity of the exposures; and
     The intensity of anticipated takes by Level B harassment 
is low for all species and stocks, consisting of, at worst, temporary 
modifications in behavior, and would not be of a duration or intensity 
expected to result in impacts on reproduction or survival of 
individuals.

Cook Inlet Beluga Whale

    For Cook Inlet beluga whales, we further discuss our negligible 
impact analysis in addition to the assessment above for all species in 
the context of potential impacts to this endangered stock based on our 
evaluation of the take proposed to be authorized (table 13).
    All tugging activities would be done in a manner implementing best 
management practices to preserve water quality, and no work would occur 
around creek mouths or river systems leading to prey abundance 
reductions. In addition, no physical structures would restrict passage; 
however, impacts to the acoustic habitat are relevant and discussed 
here.While the specified activity would occur within Cook Inlet beluga 
whale Critical Habitat Area 2 (and potentially Area 1, depending on the 
origin of the tug tow), and recognizing that Cook Inlet beluga whales 
have been identified as a small and resident population, monitoring 
data from Hilcorp's activities suggest that tugging activities do not 
discourage Cook Inlet beluga whales from transiting throughout Cook 
Inlet and between critical habitat areas and that the whales do not 
abandon critical habitat areas (Horsley and Larson, 2023). In addition, 
large numbers of Cook Inlet beluga whales have continued to use Cook 
Inlet and pass through the area, likely traveling to critical foraging 
grounds found in upper Cook Inlet, while noise-producing anthropogenic 
activities, including vessel use, have taken place during the past two 
decades (e.g., Shelden et al. 2013, 2015, 2017, 2022; Shelden and Wade 
2019; Geotz et al. 2023). These findings are not surprising as food is 
a strong motivation for marine mammals. As described in Forney et al. 
(2017), animals typically favor particular areas because of their 
importance for survival (e.g., feeding or breeding), and leaving may 
have significant costs to fitness (reduced foraging success, increased 
predation risk, increased exposure to other anthropogenic threats). 
Consequently, animals may be highly motivated to maintain foraging 
behavior in historical foraging areas despite negative impacts (e.g., 
Rolland et al. 2012).
    Generation of sound may result in avoidance behaviors that would be

[[Page 51130]]

limited in time and space relative to the larger availability of 
important habitat areas in Cook Inlet; however, the area ensonified by 
sound from the specified activity is anticipated to be small compared 
to the overall available critical habitat for Cook Inlet beluga whales 
to feed and travel. Therefore, the specified activity would not create 
a barrier to movement through or within important areas. We anticipate 
that disturbance to Cook Inlet beluga whales would manifest in the same 
manner as other marine mammals described above (i.e., increased 
swimming speeds, changes in the direction of travel and dive behaviors, 
increased respiration rates, decreased foraging (if such activity were 
occurring), or alterations to communication signals). We do not believe 
exposure to elevated noise levels during transit past tugging or 
construction activities would have adverse effects on individuals' 
fitness for reproduction or survival.
    Although data demonstrate that Cook Inlet beluga whales are not 
abandoning the planned project area during anthropogenic activities, 
results of an expert elicitation (EE) at a 2016 workshop, which 
predicted the impacts of noise on Cook Inlet beluga whale survival and 
reproduction given lost foraging opportunities, helped to inform our 
assessment of impacts on this stock. The 2016 EE workshop used 
conceptual models of an interim population consequences of disturbance 
(PCoD) for marine mammals (NRC, 2005; New et al. 2014; Tollit et al. 
2016) to help in understanding how noise-related stressors might affect 
vital rates (survival, birth rate and growth) for Cook Inlet beluga 
whale (King et al. 2015). NMFS (2016b) suggests that the main direct 
effects of noise on Cook Inlet beluga whales are likely to be through 
masking of vocalizations used for communication and prey location and 
habitat degradation. The 2016 workshop on Cook Inlet beluga whales was 
specifically designed to provide regulators with a tool to help 
understand whether chronic and acute anthropogenic noise from various 
sources and projects are likely to be limiting recovery of the Cook 
Inlet beluga whale population. The full report can be found at https://www.smruconsulting.com/publications/ with a summary of the expert 
elicitation portion of the workshop below.
    For each of the noise effect mechanisms chosen for EE, the experts 
provided a set of parameters and values that determined the forms of a 
relationship between the number of days of disturbance a female Cook 
Inlet beluga whale experiences in a particular period and the effect of 
that disturbance on her energy reserves. Examples included the number 
of days of disturbance during the period of April, May, and June that 
would be predicted to reduce the energy reserves of a pregnant Cook 
Inlet beluga whale to such a level that she is certain to terminate the 
pregnancy or abandon the calf soon after birth, the number of days of 
disturbance in the period of April-September required to reduce the 
energy reserves of a lactating Cook Inlet beluga whale to a level where 
she is certain to abandon her calf, and the number of days of 
disturbance where a female fails to gain sufficient energy by the end 
of summer to maintain herself and her calf during the subsequent 
winter. Overall, median values ranged from 16 to 69 days of disturbance 
depending on the question. However, for this elicitation, a ``day of 
disturbance'' was defined as any day on which an animal loses the 
ability to forage for at least one tidal cycle (i.e., it forgoes 50-100 
percent of its energy intake on that day). The day of disturbance 
considered in the context of the report is notably more severe than the 
Level B harassment expected to result from these activities, which as 
described is expected to be comprised predominantly of temporary 
modifications in the behavior of individual Cook Inlet beluga whales 
(e.g., faster swim speeds, longer dives, decreased sighting durations, 
alterations in communication). Also, NMFS proposes to authorize 11 
instances of take by Level B harassment during each year, with the 
instances representing disturbance events within a day--this means that 
either 11 different individual Cook Inlet beluga whales are disturbed 
on no more than 1 day each, or some lesser number of individuals may be 
disturbed on more than 1 day, but with the total number of takes not 
exceeding 11. Given the overall anticipated take, and the short 
duration of the specified activities, it is unlikely that any one Cook 
Inlet beluga whale will be disturbed on more than a couple of days. 
Further, Furie has proposed mitigation measures specific to Cook Inlet 
beluga whales whereby they would not begin tugging activities should a 
Cook Inlet beluga whale be observed at any distance. While take by 
Level B harassment (behavioral disturbance) would be authorized, this 
measure, along with other mitigation measures described herein, would 
limit the severity of the effects of that Level B harassment to 
behavioral changes such as increased swim speeds, changes in diving and 
surfacing behaviors, and alterations to communication signals, not the 
loss of foraging capabilities. Finally, take by mortality, serious 
injury, or Level A harassment of Cook Inlet beluga whales is not 
anticipated or proposed to be authorized.
    In summary and as described above, the additional following factors 
primarily support our preliminary determination that the impacts 
resulting from this activity are not expected to adversely affect the 
Cook Inlet beluga whale through effects on annual rates of recruitment 
or survival:
     The area of exposure would be limited to habitat primarily 
used for transiting, and not areas known to be of particular importance 
for feeding or reproduction;
     The activities are not expected to result in Cook Inlet 
beluga whales abandoning critical habitat nor are they expected to 
restrict passage of Cook Inlet beluga whales within or between critical 
habitat areas; and
     Any disturbance to Cook Inlet beluga whales is expected to 
be limited to temporary modifications in behavior, and would not be of 
a duration or intensity expected to result in impacts on reproduction 
or survival.
    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take proposed for Year 1 of activity will have a negligible 
impact on all affected marine mammal species or stocks. Separately, 
NMFS preliminary finds that the total marine mammal take proposed for 
Year 2 of activity will have a negligible impact on all affected marine 
mammal species or stocks.

Small Numbers

    As noted previously, take of only small numbers of marine mammals 
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. When the predicted number of 
individuals to be taken is fewer than one-third of the species or stock 
abundance, the take is considered to be of small numbers. Additionally, 
other qualitative factors may be considered in the analysis, such

[[Page 51131]]

as the temporal or spatial scale of the activities.
    Table 13 provides the quantitative analysis informing our small 
numbers determinations for the Year 1 and Year 2 IHAs. For all stocks 
whose abundance estimate is known, the amount of taking is less than 
one-third of the best available population abundance estimate (in fact 
it is less than 1 percent for all stocks, except for Cook Inlet beluga 
whales whose proposed take is 3.9 percent of the stock; table 13). The 
number of animals proposed for authorization to be taken from these 
stocks therefore, would be considered small relative to the relevant 
stock's abundances even if each estimated take occurred to a new 
individual.
    Abundance estimates for the Mexico-North Pacific stock of humpback 
whales are based upon data collected more than 8 years ago and, 
therefore, current estimates are considered unknown (Young et al. 
2023). The most recent minimum population estimates (NMIN) 
for this population include an estimate of 2,241 individuals between 
2003 and 2006 (Martinez-Aguilar 2011) and 766 individuals between 2004 
and 2006 (Wade 2021). NMFS' Guidelines for Assessing Marine Mammal 
Stocks suggest that the NMIN estimate of the stock should be 
adjusted to account for potential abundance changes that may have 
occurred since the last survey and provide reasonable assurance that 
the stock size is at least as large as the estimate (NMFS 2023b). The 
abundance trend for this stock is unclear; therefore, there is no basis 
for adjusting these estimates (Young et al. 2023). Assuming the 
population has been stable, and that the 3 takes of humpback whale 
proposed for authorization would all be of the Mexico-North Pacific 
stock, this represents small numbers of this stock (less than 1 percent 
of the stock assuming an NMIN of 2,241 individuals and <1 
percent of the stock assuming an NMIN of 766 individuals).
    A lack of an accepted stock abundance value for the Alaska stock of 
minke whale did not allow for the calculation of an expected percentage 
of the population that would be affected during each year. The most 
relevant estimate of partial stock abundance is 1,233 minke whales in 
coastal waters of the Alaska Peninsula and Aleutian Islands (Zerbini et 
al. 2006). Given three takes by Level B harassment proposed for 
authorization for the stock during Year 1 and Year 2, comparison to the 
best estimate of stock abundance shows, at most, less than 1 percent of 
the stock would be expected to be impacted.
    There is no stock-wide abundance estimate for Northeast Pacific fin 
whales. However, Young et al. (2022) estimate the minimum stock size 
for the areas surveyed is 2,554. Given 2 takes by Level B harassment 
proposed for authorization for the stock during Year 1 and Year 2, 
comparison to the minimum population estimate shows, at most, less than 
1 percent of the stock would be expected to be impacted.
    The Alaska stock of Dall's porpoise has no official NMFS abundance 
estimate for this area, as the most recent estimate is greater than 8 
years old. As described in the 2022 Alaska SAR (Young et al. 2023) the 
minimum population estimate is assumed to correspond to the point 
estimate of the 2015 vessel-based abundance computed by Rone et al. 
(2017) in the Gulf of Alaska (N = 13,110; CV = 0.22). Given 6 takes by 
Level B harassment proposed for authorization for the stock during Year 
1 and Year 2, comparison to the minimum population estimate shows, at 
most, less than 1 percent of the stock would be expected to be 
impacted.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals would be taken relative to the population 
size of the affected species or stocks for the Year 1 IHA. Separately, 
NMFS also preliminarily finds that small numbers of marine mammals will 
be taken relative to the population size of the affected species or 
stocks for the Year 2 IHA.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue an IHA, 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.
    Subsistence communities identified as project stakeholders near 
Furie's middle Cook Inlet (and potentially Trading Bay, depending on 
where Furie takes over the rig from Hilcorp) activities include the 
Village of Salamatof and the Native Village of Tyonek. The Alaska 
Department of Fish and Game Community Subsistence Information System 
does not contain data for Salamatof. For the purposes of our analyses 
for the Year 1 and Year 2 IHAs, we assume the subsistence uses are 
similar to those of nearby communities such as Kenai. Tyonek, on the 
western side of lower Cook Inlet, has a subsistence harvest area that 
extends from the Susitna River south to Tuxedni Bay (BOEM 2016). In 
Tyonek, harbor seals were harvested between June and September by 6 
percent of the households (Jones et al. 2015). Seals were harvested in 
several areas, encompassing an area stretching 32.2 km (20 mi) along 
the Cook Inlet coastline from the McArthur Flats north to the Beluga 
River. Seals were searched for or harvested in the Trading Bay areas as 
well as from the beach adjacent to Tyonek (Jones et al. 2015). 
Subsistence hunting of whales is not known to currently occur in Cook 
Inlet.
    Furie's tug towing rig activities may overlap with subsistence 
hunting of seals. However, these activities typically occur along the 
shoreline or very close to shore near river mouths, whereas most of 
Furie's tugging (all, with the exception of returning the rig to the 
Rig Tender's Dock, located in an industrialized area of Nikiski, 
Alaska), as well as its pile driving, is in the middle of the Inlet and 
rarely near the shoreline or river mouths. Any harassment to harbor 
seals is anticipated to be short-term, mild, and not result in any 
abandonment or behaviors that would make the animals unavailable for 
harvest. However, to further minimize any potential effects of their 
action on subsistence activities, Furie plans to conduct stakeholder 
outreach before the planned operations in 2024 and 2025, according to 
its Stakeholder Engagement Plan. According to Furie, they contacted 
Alaska Native Tribes in the Cook Inlet Region by email and phone 
message. To date, Furie has not received any responses from the Tribes. 
Furie states it will expand the effort to include Cook Inlet Regional 
Inc. and Chugach Alaska Corporation and will continue to reach out to 
the Tribes as the project nears. Furie must coordinate with local 
Tribes as described in its Stakeholder Engagement Plan, notify the 
communities of any changes in the operation, and take action to avoid 
or mitigate impacts to subsistence harvests.
    Based on the description of the specified activity, the measures 
described to minimize adverse effects on the availability of marine 
mammals

[[Page 51132]]

for subsistence purposes, and the proposed mitigation and monitoring 
measures, NMFS has preliminarily determined that there will not be an 
unmitigable adverse impact on subsistence uses from Furie's proposed 
activities under the Year 1 IHA. Separately, NMFS has also 
preliminarily determined that there will not be an unmitigable adverse 
impact on subsistence uses from Furie's proposed activities under the 
Year 2 IHA.

Endangered Species Act

    Section 7(a)(2) of the ESA of 1973 (16 U.S.C. 1531 et seq.) 
requires that each Federal agency insure that any action it authorizes, 
funds, or carries out is not likely to jeopardize the continued 
existence of any endangered or threatened species or result in the 
destruction or adverse modification of designated critical habitat. To 
ensure ESA compliance for the issuance of IHAs, NMFS consults 
internally whenever we propose to authorize take for endangered or 
threatened species, in this case with the NMFS Alaska Regional Office 
(AKRO).
    NMFS is proposing to authorize take of fin whale, humpback whale 
(Mexico Distinct Population Segment (DPS), beluga whale (Cook Inlet), 
and Steller sea lion (Western DPS), which are listed under the ESA. The 
Permits and Conservation Division has requested initiation of section 7 
consultation with the NMFS AKRO for the issuance of this IHA. NMFS will 
conclude the ESA consultation prior to reaching a determination 
regarding the proposed issuance of the authorization.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue two IHAs to Furie for conducting oil and gas activities in Cook 
Inlet, Alaska from 2024-2026, provided the previously mentioned 
mitigation, monitoring, and reporting requirements are incorporated. 
Drafts of the proposed IHAs can be found at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this notice of proposed IHAs for the proposed oil 
and gas activities. We also request comment on the potential renewal of 
these proposed IHAs as described in the paragraph below. Please include 
with your comments any supporting data or literature citations to help 
inform decisions on the proposed IHAs or a subsequent renewal IHA.
    On a case-by-case basis, NMFS may issue a one-time, 1-year renewal 
IHA following notice to the public providing an additional 15 days for 
public comments when (1) up to another year of identical or nearly 
identical activities as described in the Description of Proposed 
Activity section of this notice is planned; or (2) the activities as 
described in the Description of Proposed Activity section of this 
notice would not be completed by the time the IHA expires and a renewal 
would allow for completion of the activities beyond that described in 
the Dates and Duration section of this notice, provided all of the 
following conditions are met:
     A request for renewal is received no later than 60 days 
prior to the needed renewal IHA effective date (recognizing that the 
renewal IHA expiration date cannot extend beyond one year from 
expiration of the initial IHA).
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested renewal IHA are identical to the activities analyzed under 
the initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take); 
and
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized;
     Upon review of the request for renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: June 10, 2024.
Angela Somma,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2024-13000 Filed 6-13-24; 8:45 am]
BILLING CODE 3510-22-P