Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to BlueCrest Alaska Operating, LLC Drilling Activities at Cosmopolitan State Unit, Alaska, 2016, 35547-35578 [2016-12886]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 81, Number 106 (Thursday, June 2, 2016)]
[Notices]
[Pages 35547-35578]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-12886]



[[Page 35547]]

Vol. 81

Thursday,

No. 106

June 2, 2016

Part IV





 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 BlueCrest Alaska Operating, LLC Drilling 
Activities at Cosmopolitan State Unit, Alaska, 2016; Notice

Federal Register / Vol. 81 , No. 106 / Thursday, June 2, 2016 / 
Notices

[[Page 35548]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XE497


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to BlueCrest Alaska Operating, LLC 
Drilling Activities at Cosmopolitan State Unit, Alaska, 2016

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments.

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SUMMARY: NMFS has received an application from BlueCrest Alaska 
Operating, LLC (BlueCrest) for an Incidental Harassment Authorization 
(IHA) to take marine mammals, by harassment, incidental to conducting 
an oil and gas production drilling program in lower Cook Inlet, AK, on 
State of Alaska Oil and Gas Lease 384403 under the program name of 
Cosmopolitan State during the 2016 open water season. Pursuant to the 
Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its 
proposal to issue an IHA to BlueCrest to incidentally take, by Level B 
harassment only, marine mammals during the specified activity.

DATES: Comments and information must be received no later than July 5, 
2016.

ADDRESSES: Comments on the application should be addressed to Jolie 
Harrison, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service, 1315 East-West Highway, 
Silver Spring, MD 20910. The mailbox address for providing email 
comments is ITP.Youngkin@noaa.gov. NMFS is not responsible for email 
comments sent to addresses other than the one provided here. Comments 
sent via email, including all attachments, must not exceed a 25-
megabyte file size.
    Instructions: All comments received are a part of the public record 
and will generally be posted to https://www.nmfs.noaa.gov/pr/permits/incidental.htm 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.
    An electronic copy of the application, NMFS' Draft Programmatic 
Environmental Assessment (EA) for activities in Cook Inlet, and a list 
of the references used in this document may be obtained by visiting the 
Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. In 
case of problems accessing these documents, please call the contact 
listed below. Documents cited in this notice may also be viewed, by 
appointment, during regular business hours, at the aforementioned 
address.

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

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization 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), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking; other means of 
effecting the least practicable impact on the species or stock and its 
habitat; and requirements pertaining to the mitigation, monitoring and 
reporting of such takings are set forth. NMFS has defined ``negligible 
impact'' in 50 CFR 216.103 as ``. . . an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival.''
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: ``any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].''

Summary of Request

    On September 28, 2015 NMFS received an IHA application from 
BlueCrest for the taking of marine mammals incidental to an oil and gas 
production drilling program in lower Cook Inlet, AK, during the 2016 
open water season. Typically, the open water (i.e., ice-free) season is 
mid-April through October; however, BlueCrest would only operate during 
a portion of this season, from August 1, 2016 through October 31, 2016. 
NMFS determined that the application was adequate and complete on April 
12, 2016.
    BlueCrest proposes to conduct and oil and gas production drilling 
program using the Spartan 151 drill rig (or similar rig) in lower Cook 
Inlet. This work would include drilling up to three wells with a total 
operating time of approximately 91 days during the 2016 open-water 
season, (August 1 through October 31). In 2013, BlueCrest, then in 
partnership with Buccaneer Energy, conducted exploratory oil and gas 
drilling at the Cosmopolitan State #A-1 well site (then called 
Cosmopolitan State #1). Beginning in 2016, BlueCrest intends to drill 
two more wells (Cosmopolitan State #A-2 and #A-3). These directionally 
drilled wells have top holes located a few meters from the original 
Cosmopolitan State #A-1, and together would feed to a future single 
offshore platform. Both #A-2 and #A-3 may involve test drilling into 
oil layers. After testing, the oil horizons will be plugged and 
abandoned, while the gas zones will be suspended pending platform 
construction. A third well (#B-1) will be located approximately 1.7 
kilometers (km; 1 mile [mi]) southeast of the other wells. This well 
will be drilled into oil formations to collect geological information. 
After testing, the oil horizon will be plugged and abandoned, while the 
gas zones will be suspended pending platform construction. All four 
wells (one existing and up to three new) would be located within Lease 
384403. Specific locations (latitude and longitude and depth) of each 
well is provided in Table 1-1 and depicted in Figure 1-1 of BlueCrest's 
application.
    The following specific aspects of the proposed activities are 
likely to result in the take of marine mammals: (1) Impact hammering of 
the drive pipe at the well prior to drilling, and (2) vertical seismic 
profiling (VSP). Underwater noise associated with drilling and rig 
operation associated with the specified activity has been determined to 
have little effect on marine mammals (based on Marine Acoustics, Inc.'s 
[2011] acoustical testing of the Spartan 151 while drilling). Take, by 
Level B harassment only, of nine marine mammal species is anticipated 
to result from the specified activity.

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Description of the Specified Activity

Overview

    BlueCrest proposes to conduct oil and gas production drilling 
operations at up to three sites in lower Cook Inlet during the 2016 
open water (ice-free) season (August 1 through October 31), using the 
Spartan 151 jack-up drill rig, depending on availability. The 
activities of relevance to this IHA request include: Impact hammering 
of the drive pipe and VSP seismic operations. BlueCrest proposes to 
mobilize and demobilize the drill rig to and from the well locations, 
and will utilize both helicopters and vessels to conduct resupply, crew 
change, and other logistics during the drilling program. These 
mobilization/demobilization activities, and actual drilling/operation 
of the rig, are also part of the proposed activity but are not 
considered activities of relevance to this IHA because take is not 
being authorized for those activities. More information regarding these 
activities and why they are/are not considered activities of relevance 
to this IHA can be found in the Detailed Description of Activities 
section below.

Dates and Duration

    The 2016 drilling program (which is the subject of this IHA 
request) would occur during the 2016 open water season (August 1 
through October 31). BlueCrest estimates that the drilling period could 
take up to 91 days in the above time period. The exact start date is 
currently unknown, and dependent on the scheduling availability of the 
proposed drill rig. It is expected that each well will take 
approximately 30 days to complete, including well testing time.
    During this time period, drive pipe hammering would only occur for 
a period of 1 to 3 days at each well site (although actual sound 
generation would occur only intermittently during this time period), 
and VSP seismic operations would only occur for a period of less than 1 
to 2 days at each well site. This IHA (if issued) would be effective 
for 1 year, beginning on August 1, 2016.

Specified Geographic Region

    BlueCrest's proposed program would occur at Cosmopolitan State #B-1 
(originally Cosmopolitan #2), Cosmopolitan State #A-1 (originally 
Cosmopolitan State #1), #A-2, and #A-3 in lower Cook Inlet, AK. The 
exact location of BlueCrest's well sites can be seen in Figure 1-1 in 
BlueCrest's IHA application and location information (latitude/
longitude and water depth) is provided in Table 1-1 in the IHA 
application.

Detailed Description of Activities

1. Drill Rig Mobilization and Towing

    BlueCrest proposes to conduct its production and exploratory 
drilling using the Spartan 151 drill rig or similar rig (see Figure 1-2 
of the IHA application). The Spartan 151 is a 150 H class independent 
leg, cantilevered jack-up drill rig, with a drilling capability of 
25,000 ft but can operate in maximum water depths up to only 150 ft. 
The rig will be towed by ocean-going tugs licensed to operate in Cook 
Inlet. While under tow, the rig operations will be monitored by 
BlueCrest and the drilling contractor management, both aboard the rig 
and onshore.
    The Spartan 151 is currently moored at the Seward Marine Industrial 
Center, directly across Resurrection Bay from the City of Seward. The 
intention is to move the drill rig to the Cosmopolitan Site #B-1 well 
site in July, a distance of approximately 314 km (195 miles [mi]). It 
is anticipated that this tow would be accomplished within three days. 
Any move post-project will be controlled by the owner of the drilling 
rig. The rig will be towed between locations by ocean-going tugs that 
are licensed to operate in Cook Inlet. Move plans will receive close 
scrutiny from the rig owner's tow master as well as the owner's 
insurers, and will be conducted in accordance with state and federal 
regulations. Rig moves will be conducted in a manner to minimize any 
potential risk regarding safety as well as cultural or environmental 
impact.
    The rig will be wet-towed by two or three ocean-going tugs licensed 
to operate in Cook Inlet. Ship strike of marine mammals during tow is 
not an issue of major concern. Most strikes of marine mammals occur 
when vessels are traveling at speeds between 24 and 44 km/hr (13 and 24 
knots [kt]) (https://www.nmfs.noaa.gov/pr/pdfs/shipstrike/ss_speed.pdf), 
well above the 1.9- to 7.4-km/hr (1- to 4-kt) drill rig tow speed 
expected. However, noise from towing was considered as a potential 
impact. Tugs generate their loudest sounds while towing due to 
propeller cavitation. While these continuous sounds have been measured 
at up to 171 dB re 1 [mu]Pa-m (rms) at 1-meter source (broadband), they 
are generally emitted at dominant frequencies of less than 5 kHz (Miles 
et al., 1987; Richardson et al., 1995a, Simmonds et al., 2004). For the 
most part, the dominant noise frequencies from propeller cavitation are 
significantly lower than the dominant hearing frequencies for pinnipeds 
and toothed whales, including beluga whales (Wartzok and Ketten, 1999), 
so towing activities are not considered an activity that would `take' 
marine mammals.

2. Drive Pipe Hammering

    A drive pipe is a relatively short, large-diameter pipe driven into 
the sediment prior to the drilling of oil wells. This section of tubing 
serves to support the initial sedimentary part of the well, preventing 
the looser surface layer from collapsing and obstructing the wellbore. 
Drive pipes are usually installed using pile driving techniques. The 
term `drive pipe' is often synonymous to the term `conductor pipe'; 
however, a 50.8-centimeter (cm; 20-inch [in]) conductor pipe will be 
drilled (not hammered) inside the drive pipe, and will be used to 
transport (conduct) drillhead cuttings to the surface. Therefore, there 
is no noise concern associated with the conductor pipe drilling, and 
the potential for acoustical harassment of marine mammals is due to the 
hammering of the drive pipe. BlueCrest proposes to drive approximately 
200 ft (60 m) below mudline of 30-inch drive pipe at each of the well 
sites prior to drilling using a Delmar D62-22 impact hammer. This 
hammer has impact weight of 13,640 pounds (6,200 kg) and reaches 
maximum impact energy of 165,215 foot-pounds (224 kilonewton-meters) at 
a drop height of 12 ft (3.6 m).
    Blackwell (2005) measured the noise produced by a Delmar D62-22 
driving 36-inch steel pipe in upper Cook Inlet and found sound pressure 
levels (SPLs) to exceed 190 dB re 1[mu]Pa-m (rms) at about 200 ft (60 
m), 180 dB re 1[mu]Pa-m (rms) at about 820 ft (250 m), and 160 dB re 
1[mu]Pa-m (rms) at just less than 1.2 mi (1.9 km). Illingworth and 
Rodkin (2014) measured the hammer noise operating from another rig, the 
Endeavour, in 2013 and found SPLs to exceed 190 dB re 1[mu]Pa-m (rms) 
at about 180 ft (55 m), 180 dB re 1[mu]Pa-m (rms) at about 560 ft (170 
m), and 160 dB re 1[mu]Pa-m (rms) at 1 mi (1.6 km). The drive pipe 
driving event is expected to last 1 to 3 days at each well site, 
although actual sound generation (pounding) would occur only 
intermittently during this period.

3. Drilling and Standard Operation

    The Spartan 151 was hydro-acoustically measured by Marine 
Acoustics, Inc. while operating in 2011. The survey results showed that 
continuous noise levels exceeding 120 dB re 1[mu]Pa (NMFS' current 
threshold for estimating Level B harassment from continuous underwater 
noise) extended

[[Page 35550]]

out only 164 ft (50 m), and that this sound was largely associated with 
the diesel engines used as hotel power generators.
    Deep well pumps were not identified as a sound source by Marine 
Acoustics, Inc. (2011) during their acoustical testing of the Spartan 
151, and are not considered an activity that would `take' marine 
mammals.

4. Vertical Seismic Profiling

    Once a well is drilled, accurate follow-up seismic data can be 
collected by placing a receiver at known depths in the borehole and 
shooting a seismic airgun at the surface near the borehole. These 
gathered data not only provide high resolution images of the geological 
layers penetrated by the borehole but can be used to accurately 
correlate (or correct) the original surface seismic data. The procedure 
is known as vertical seismic profiling (VSP).
    BlueCrest intends to conduct VSP operations at the end of drilling 
each well using an array of airguns with total volumes of between 600 
and 880 cubic inches (in\3\). The VSP operation is expected to last 
less than 1 or 2 days at each well site. Assuming a 1-meter source 
level of 227 dB re 1[mu]Pa (based on manufacturer's specifications) for 
an 880 in\3\ array and using Collins et al.'s (2007) transmission loss 
model for Cook Inlet (227 - 18.4 Log(R) - 0.00188), the 190 dB radius 
from the source was estimated at 330 ft (100 m), the 180 dB radius at 
1,090 ft (332 m), and the 160 dB radius at 1.53 mi (2.46 km). 190 dB 
and 180 dB are the current NMFS thresholds for estimating Level A 
harassment from underwater noise exposure for pinnipeds and cetaceans, 
respectively, and 160 dB is the current NMFS threshold for estimating 
Level B harassment from exposure to underwater impulse noises. 
Therefore, VSP operations are considered an activity that has the 
potential to `take' marine mammals.
    Illingworth and Rodkin (2014) measured the underwater sound levels 
associated with a July 2013 VSP operation using a 750 in\3\ array and 
found sound levels exceeding 160 dB re 1 [mu]Pa (rms) extended out 1.54 
mi (2.47 km), virtually identical to the modeled distance. The measured 
radius to 190 dB was 394 ft (120 m) and to 180 dB was 787 ft (240 m).

5. Helicopter and Supply Vessel Support

    Helicopter logistics for project operations will include 
transportation for personnel, groceries, and supplies. Helicopter 
support will consist of a twin turbine Bell 212 (or equivalent) 
helicopter certified for instrument flight rules land and over water 
operations. Helicopter crews and support personnel will be housed in 
existing Kenai area facilities. The helicopter will be based at the 
Kenai Airport to support rig crew changes and cargo handling. Fueling 
will take place at these facilities. No helicopter refueling will take 
place on the rig.
    Helicopter flights to and from the rig are expected to average two 
per day. Flight routes will follow a direct route to and from the rig 
location, and flight heights will be maintained 1,000 to 1,500 feet 
above ground level to avoid take of marine mammals (Richardson et al., 
1995a). At these altitudes, there are not expected to be impacts from 
sound generation on marine mammals, and are not considered an activity 
that would `take' marine mammals. The aircraft will be dedicated to the 
drilling operation and will be available for service 24 hours per day. 
A replacement aircraft will be available when major maintenance items 
are scheduled.
    Major supplies will be staged on-shore at the Kenai OSK Dock. 
Required supplies and equipment will be moved from the staging area by 
contracted supply vessels and loaded aboard the rig when the rig is 
established on a drilling location. Major supplies will include fuel, 
drilling water, mud materials, cement, casing, and well service 
equipment. Supply vessels also will be outfitted with fire-fighting 
systems as part of fire prevention and control as required by Cook 
Inlet Spill Prevention and Response, Inc. The specific supply vessels 
have not been identified; however, typical offshore drilling support 
work vessels are of steel construction with strengthened hulls to give 
the capability of working in extreme conditions. Additional information 
about logistics and fuel and waste management can be found in Section 
1.2 of BlueCrest's IHA application.

Description of Marine Mammals in the Area of the Specified Activity

    Several marine mammal species occur in lower Cook Inlet. The marine 
mammal species under NMFS's jurisdiction include: Beluga whale 
(Delphinapterus leucas); harbor porpoise (Phocoena phocoena); killer 
whale (Orcinus orca); gray whale (Eschrichtius robustus); minke whale 
(Balaenoptera acutorostrata); Dall's porpoise (Phocoenoides dalli); 
humpback whale (Megaptera novaeangliae); harbor seal (Phoca vitulina 
richardsi); and Steller sea lion (Eumetopias jubatus).
    Data collected during marine mammal monitoring at Cosmopolitan 
State #A-1 during summer 2013 recorded at least 154 harbor porpoise 
(152 within 1.2 mi (2 km) of operation, 12 of which were observed 
inside 853 ft (260 m) of the rig); 77 harbor seals (18 of these within 
853 ft [260 m] of the active drill rig); 42 minke whales (all except 
for three recorded over 984 ft (300 m) from the active drill rig; 19 
Dall's porpoise (none in close proximity to the active drill rig); 12 
gray whales (observed offshore of Cape Starichkof; none closely 
approached drilling operations); seven Steller sea lions (none in close 
proximity to the active drill rig); 18 killer whales (17 within 1.2 mi 
(2 km) of operations); and one beluga whale (observed at a distance 
well beyond 1.8 mi (3 km) between May and August 2013 (112 days of 
monitoring). Based on their seasonal patterns, gray whales could be 
encountered in low numbers during operations. Minke whales have been 
considered migratory in Alaska (Allen and Angliss, 2014) but have 
recently been observed off Cape Starichkof and Anchor Point, including 
in winter. The remaining species could be encountered year-round. 
Humpback whales are common in the very southern part of Cook Inlet and 
typically do not venture north of Kachemak Bay (B. Mahoney, NMFS, pers. 
comm., August 2014), which is south of the proposed Cosmopolitan 
drilling site. Therefore, while it is unlikely that humpback whales, 
gray whales, or minke whales would be encountered during the proposed 
project, it is still a possibility based on observations from past 
monitoring efforts, and therefore take of these species was requested.
    Of these marine mammal species, Cook Inlet beluga whales, humpback 
whales, and the western distinct population segment (DPS) of Steller 
sea lions are listed as endangered under the Endangered Species Act 
(ESA). The eastern DPS of Steller sea lions was recently removed from 
the endangered species list (78 FR 66139, November 4, 2013) but 
currently retains its status as ``depleted'' under the MMPA along with 
the western DPS, Cook Inlet beluga whales, and humpback whales.
    Despite these designations, Cook Inlet beluga whales and the 
western DPS of Steller sea lions have not made significant progress 
towards recovery. Data indicate that the Cook Inlet population of 
beluga whales decreased at a rate of 0.6 percent annually between 2002 
and 2012 (Allen and Angliss, 2014). The NMFS 2014 Stock Assessment 
Report (SAR) estimated 312 Cook Inlet beluga whales, which is a three-
year average. However, the most

[[Page 35551]]

recent abundance estimate is 340 beluga whales (Shelden et al., 2015).
    Regional variation in trends in Western DPS Steller sea lion pup 
counts in 2000-2012 is similar to that of non-pup counts (Johnson and 
Fritz, 2014). Overall, there is strong evidence that pup counts in the 
western stock in Alaska increased (1.45 percent annually). Between 2004 
and 2008, Alaska western non-pup counts increased only 3%: Eastern Gulf 
of Alaska (Prince William Sound area) counts were higher and Kenai 
Peninsula through Kiska Island counts were stable, but western Aleutian 
counts continued to decline. Johnson and Fritz (2014) analyzed western 
Steller sea lion population trends in Alaska and noted that there was 
strong evidence that non-pup counts in the western stock in Alaska 
increased between 2000 and 2012 (average rate of 1.67 percent 
annually). However, there continues to be considerable regional 
variability in recent trends across the range in Alaska, with strong 
evidence of a positive trend east of Samalga Pass and strong evidence 
of a decreasing trend to the west (Allen and Angliss, 2014).
    The Central North Pacific humpback whale stock, consisting of 
winter/spring populations of the Hawaiian Islands which migrate 
primarily to northern British Columbia/Southeast Alaska, the Gulf of 
Alaska, and the Bering Sea/Aleutian Islands (Baker et al., 1990; Perry 
et al., 1990; Calambokidis et al., 1997), has increased over the past 
two decades. Different studies and sampling techniques in Hawaii and 
Alaska have indicated growth rates ranging from 4.9-10 percent per year 
in the 1980s, 1990s, and early 2000s (Mobley et al., 2001; Mizroch et 
al., 2004; Zerbini et al., 2006; Calambokidis et al., 2008). It is also 
clear that the abundance has increased in Southeast Alaska, though a 
trend for the Southeast Alaska portion of this stock cannot be 
estimated from the data because of differences in methods and areas 
covered (Allen and Angliss, 2013). On April 21, 2015, NMFS published a 
notice in the Federal Register requesting comments on a proposal to 
revise the listing status of humpback whales by delineating the species 
into 14 DPS, changing the Central North Pacific stock of humpback 
whales to become the Hawaii DPS. NMFS also proposed to delist the 
Hawaii DPS (80 FR 22304).
    Pursuant to the ESA, critical habitat has been designated for Cook 
Inlet beluga whales and Steller sea lions. The proposed drilling 
program does not fall within critical habitat designated in Cook Inlet 
for beluga whales or within critical habitat designated for Steller sea 
lions. The Cosmopolitan State unit is nearly 100 miles south of beluga 
whale Critical Habitat Area 1 and approximately 27 miles south of 
Critical Habitat Area 2. It is also located about 25 miles north of the 
isolated patch of Critical Habitat Area 2 found in Kachemak Bay. Area 2 
is based on dispersed fall and winter feeding and transit areas in 
waters where whales typically appear in smaller densities or deeper 
waters (76 FR 20180, April 11, 2011). No critical habitat has been 
designated for humpback whales.
    BlueCrest is requesting take of belugas, humpback whales and 
Steller sea lions, which have been observed in close proximity to the 
Cosmopolitan site (G. Green, Owl Ridge, personal communication). In 
addition, BlueCrest is requesting take of gray, minke, and killer 
whales, harbor and Dall's porpoise, and harbor seals. See Table 1 below 
for more information on the habitat, range, population, and status of 
these species.

                   Table 1--The Habitat, Abundance, and Conservation Status of Marine Mammals
----------------------------------------------------------------------------------------------------------------
                                                                        Best Population
            Species                   Habitat             Range             Estimate        ESA \2\    MMPA \3\
                                                                         (Minimum) \1\
----------------------------------------------------------------------------------------------------------------
Humpback whale (Megaptera        Coastal and        Worldwide in all   10,103--Central    EN          D, S.
 novaeangliae).                   inland waters.     ocean basins.      N. Pacific Stock.
Minke Whale (Balaenoptera        Coastal and        Bering and         1,233 \2\--Alaska  NL          NC.
 acutorostra).                    inland waters.     Chukchi Seas       stock.
                                                     south to near
                                                     the Equator.
Gray Whale (Eschrichtius         Coastal and        North Pacific      20,990 \3\--E.     NL          NC.
 robustus).                       inland waters.     from Alaska to     North Pacific
                                                     Mexico.            Stock.
Beluga Whale (Delphinapterus     Offshore waters    Ice-covered        340--Cook Inlet    EN          D, S.
 leucas).                         in winter;         arctic and         stock.
                                  coastal/           subartic waters
                                  estuarine waters   of the Northern
                                  in spring.         Hemisphere.
Killer Whale (Orcinus orca)....  Offshore to        Throughout North   2,347--Alaska      NL          NC.
                                  inland waterways.  Pacific; along     resident stock/
                                                     west coast of      587 Alaska
                                                     North America;     transient stock.
                                                     entire Alaskan
                                                     coast.
Harbor Porpoise (Phocoena        Coastal..........  Point Barrow,      31,046--Gulf of    NL          S.
 phocoena).                                          Alaska to Point    Alaska stock.
                                                     Conception,
                                                     California.
Dall's Porpoise (Phocoenoides    Over continental   Throughout North   83,400--Alaska     NL          NC.
 dalli).                          shelf adjacent     Pacific.           stock.
                                  to slope and
                                  over deep
                                  oceanic waters.
Pacific harbor seal (Phoca       Coastal and        Coastal temperate  22,900--Cook       NL          NC.
 vitulina richardii).             Estuarine.         to polar regions   Inlet/Shelikof
                                                     in Northern        stock.
                                                     Hemisphere.
Steller Sea Lion (Eumetopias     Coastal..........  Northern Pacific   55,422--W. U.S.    NL          D, S.
 jubatus).                                           Rim from           stock.
                                                     northern Japan
                                                     to California.
----------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ Allen and Angliss (2015).
\2\ Zerbini et al. (2006).
\3\ Caretta et al. (2015).
\4\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, DL = Delisted, and NL = Not listed.
\5\ U.S. Marine Mammal Protection Act: D = Depleted, S = Strategic, and NC = Not classified.


[[Page 35552]]

Cetaceans

Beluga Whale (Delphinapterus leucas)
    The Cook Inlet beluga whale DPS is a small geographically isolated 
population that is separated from other beluga populations by the 
Alaska Peninsula. The population is genetically (mtDNA) distinct from 
other Alaska populations suggesting the Peninsula is an effective 
barrier to genetic exchange (O'Corry-Crowe et al. 1997) and that these 
whales may have been separated from other stocks at least since the 
last ice age. Laidre et al. (2000) examined data from more than 20 
marine mammal surveys conducted in the northern Gulf of Alaska and 
found that sightings of belugas outside Cook Inlet were exceedingly 
rare, and these were composed of a few stragglers from the Cook Inlet 
DPS observed at Kodiak Island, Prince William Sound, and Yakutat Bay. 
Several marine mammal surveys specific to Cook Inlet (Laidre et al. 
2000, Speckman and Piatt 2000), including those that concentrated on 
beluga whales (Rugh et al. 2000, 2005a), clearly indicate that this 
stock largely confines itself to Cook Inlet. There is no indication 
that these whales make forays into the Bering Sea where they might 
intermix with other Alaskan stocks.
    The Cook Inlet beluga DPS was originally estimated at 1,300 whales 
in 1979 (Calkins 1989) and has been the focus of management concerns 
since experiencing a dramatic decline in the 1990s. Between 1994 and 
1998 the stock declined 47 percent which was attributed to 
overharvesting by subsistence hunting. Subsistence hunting was 
estimated to annually remove 10 to 15 percent of the population during 
this period. Only five belugas have been harvested since 1999, yet the 
population has continued to decline, with the most recent estimate at 
only 312 animals (Allen and Angliss 2014). NMFS listed the population 
as ``depleted'' in 2000 as a consequence of the decline, and as 
``endangered'' under the Endangered Species Act (ESA) in 2008 when the 
population failed to recover following a moratorium on subsistence 
harvest. In April 2011, NMFS designated critical habitat for the beluga 
under the ESA (Figure 1).
BILLING CODE 3510-22-P

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[GRAPHIC] [TIFF OMITTED] TN02JN16.026

BILLING CODE 3510-22-C
Prior to the decline, this DPS was believed to range throughout Cook 
Inlet and occasionally into Prince William Sound and Yakutat (Nemeth et 
al. 2007). However the range has contracted coincident with the 
population reduction (Speckman and Piatt 2000). 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 paci[filig]cus) and salmon 
(Onchorhyncus spp.) (Moore et al. 2000). Critical Habitat Area

[[Page 35554]]

1 reflects this summer distribution (Figure 1). During the winter, 
beluga whales concentrate in deeper waters in the mid-inlet to Kalgin 
Island, and in the shallow waters along the west shore of Cook Inlet to 
Kamishak Bay (Critical Habitat Area 2; Figure 1). Some whales may also 
winter in and near Kachemak Bay.

    The Cosmopolitan State lease does not fall within beluga whale 
critical habitat. Based on Goetz et al. (2012) beluga whale densities, 
both along the route from Port Graham and at the well site, are very 
low (<0.01 whales/km\2\). In the past, beluga whales have been observed 
in Kachemak Bay, which presumably could have travelled between the bay 
and upper Cook Inlet following a route past the current location of the 
Cosmopolitan State lease. Reported observations since 1975 show most 
whale activity in Kachemak Bay occurred prior to 2000. However, in 2013 
a single beluga was sighted a few kilometers from Cosmopolitan State 
well site #A-1 (Owl Ridge 2014).
Killer Whales (Orcinus orca)
    Two different killer whale stocks inhabit the Cook Inlet region of 
Alaska: the Alaska resident stock (resident stock) and the Gulf of 
Alaska, Aleutian Islands, Bering Sea transient stock (transient stock) 
(Allen and Angliss, 2014). The Alaska resident stock occurs from 
Southeast Alaska to the Bering Sea (Allen and Angliss, 2014) and feeds 
exclusively on fish, while transient killer whales feed primarily on 
marine mammals (Saulitis et al., 2000). Killer whales are occasionally 
observed in lower Cook Inlet, especially near Homer and Port Graham 
(Shelden et al., 2003; Rugh et al., 2005). A concentration of sightings 
near Homer and inside Kachemak Bay may represent high killer whale use 
or high observer-effort given most records are from a whale-watching 
venture based in Homer. During aerial surveys conducted between 1993 
and 2004, killer whales were only observed on three flights, all in the 
Kachemak Bay and English Bay area (Rugh et al., 2005). Eighteen killer 
whales (it is unknown which stock these belonged to) were recorded 
during the May to August 2013 marine mammal monitoring activities at 
Cosmopolitan State #A-1 (Owl Ridge 2014). Based on these sightings, it 
is possible that killer whales will occur in the vicinity of the 
proposed drilling activity.
Harbor Porpoise (Phocoena phocoena)
    The most recent estimated density for harbor porpoises in Cook 
Inlet is 7.2 per 1,000 km\2\ (Dahlheim et al., 2000) indicating that 
only a small number use Cook Inlet. Harbor porpoise have been reported 
in lower Cook Inlet from Cape Douglas to the West Foreland, Kachemak 
Bay, and offshore (Rugh et al., 2005). Harbor porpoises are found 
primarily in coastal waters less than 328 ft deep (Hobbs and Waite, 
2010) where they feed primarily on Pacific herring, other schooling 
fish, and cephalopods. The diet of harbor porpoise within Cook Inlet is 
unknown, although seasonal distribution patterns of porpoise (Shelden 
et al. 2014) coincident with eulachon, longfin smelt, capelin, herring, 
and salmon concentrations (Moulton 1997) suggest these fish are 
important prey items for Cook Inlet harbor porpoise. Small numbers of 
harbor porpoises have been consistently reported in upper Cook Inlet 
between April and October, except for a recent survey that recorded 
higher than usual numbers (Prevel Ramos et al., 2008). In addition, 
recent passive acoustic research in Cook Inlet by the Alaska Department 
of Fish and Game and the National Marine Mammal Laboratory (NMML) have 
indicated that harbor porpoises occur more frequently than previously 
thought, particularly in the West Foreland area in the spring (NMML, 
2011); however overall numbers are still unknown at this time. Also, 
harbor porpoises were the most frequently sighted marine mammal species 
during monitoring in 2013 at the Cosmopolitan State #A-1 well. At least 
154 harbor porpoises were recorded during the 2013 monitoring, but only 
12 were observed inside 853 ft (260 m) of the drill rig.
Humpback whale (Megaptera novaeangliae)
    Although there is considerable distributional overlap in the 
humpback whale stocks that use Alaska, the whales seasonally found in 
lower Cook Inlet are probably of the Central North Pacific stock. 
Listed as endangered under the Endangered Species Act (ESA), this stock 
has recently been estimated at 7,469, with the portion of the stock 
that feeds in the Gulf of Alaska estimated at 2,845 animals (Allen and 
Angliss 2014). The Central North Pacific stock winters in Hawaii and 
summers from British Columbia to the Aleutian Islands (Calambokidis et 
al. 1997), including Cook Inlet.
    In the North Pacific, humpback whiles feed primarily on krill 
(especially euphausiids) and small schooling fish such including 
herring, sand lance, capelin, and eulachon (Clapham 2002). Based on 
both fecal samples and isotope analysis, Witteveen et al. (2011) found 
humpback whales near Kodiak Island to feed largely on euphausiids, 
capelin, Pacific sand lance, and juvenile walleye pollock. It is 
unknown what humpback whales seasonally occurring in Kachemak Bay and 
near Anchor Point are feeding on, but Cook Inlet seabird and forage 
fish studies (Piatt and Roseneau 1997) found large concentrations of 
sand lance in this region. Humpback use of Cook Inlet is largely 
confined to lower Cook Inlet. They have been regularly seen near 
Kachemak Bay during the summer months (Rugh et al. 2005a), and there is 
a whale-watching venture in Homer capitalizing on this seasonal event. 
There are anecdotal observations of humpback whales as far north as 
Anchor Point, with very few records to the latitude of the Cosmopolitan 
State lease area. However, 29 sightings of 48 humpback whales were 
recorded by marine mammal observers during the 2013 monitoring program 
at Cosmopolitan State well site #A-1 (Owl Ridge 2014), although nearly 
all of these animals were observed at a distance well south of the well 
site, many records were repeat sightings of the same animals, and none 
were recorded inside an active harassment zone. Due to these sightings, 
humpback whales may be encountered in the vicinity of the project and 
were included in the application for incidental take.
Gray Whale (Eschrichtius robustus)
    The gray whale is a large baleen whale known to have one of the 
longest migrations of any mammal. This whale can be found all along the 
shallow coastal waters of the North Pacific Ocean. The Eastern North 
Pacific stock, which includes those whales that travel along the coast 
of Alaska, was delisted from the ESA in 1994 after a distinction was 
made between the western and eastern populations (59 FR 31094, June 16, 
1994). The most recent estimate of abundance for the Eastern North 
Pacific stock of gray whales is 19,126, based on the 2006/2007 
southbound survey (Laake et al., 2009).
    Gray whales typically do not feed during their northward migration 
through Alaskan waters until they reach the Chukchi Sea where they 
spend the summer feeding mostly on ampeliscid amphipods, a benthic 
crustacean (Rice and Wolman 1971, Highsmith and Coyle 1992, Nelson et 
al. 1994). However, small groups of whales may opportunistically feed 
along route (Nerini 1984), with some groups actually becoming 
``resident'' at areas of high localized prey densities (Calambokidis et 
al. 2004, Estes 2006). One ``resident'' group, known as the Kodiak 
group, has been observed year-round at Ugak Bay (Kodiak Island)

[[Page 35555]]

feeding on dense populations of hooded shrimp or cumaceans 
(Diastylidae), a benthic crustacean (Moore et al. 2007). Groups of gray 
whales were recorded at the Cosmopolitan State lease site in 2013 (Owl 
Ridge 2014), mostly in July, but it was noted that these may have been 
repeated sightings of the same one or two small groups, suggesting 
seasonal foraging use of the Anchor Point area by a few whales. There 
is no information the diet of gray whales using lower Cook Inlet, but 
available prey could be similar to that found at Ugak Bay.
    Although observations of gray whales are rare within Cook Inlet, 
marine mammal observers noted individual gray whales on nine occasions 
in upper Cook Inlet in 2012 while conducting marine mammal monitoring 
for seismic survey activities under an IHA NMFS issued to Apache Alaska 
Corporation: Four times in May; twice in June; and three times in July 
(Apache, 2013). Annual surveys conducted by NMFS in Cook Inlet since 
1993 have resulted in a total of five gray whale sightings (Rugh et 
al., 2005). Although Cook Inlet is not believed to comprise either 
essential feeding or social ground, there may be some encounters in 
lower Cook Inlet. Small numbers of summering gray whales have been 
noted by fishermen near Kachemak Bay and north of Anchor Point. 
Further, summer gray whales were recorded a dozen times offshore of 
Cape Starichkof by observers monitoring BlueCrest's Cosmopolitan #A-1 
drilling program between May and August 2013. However, as noted above, 
these may have been repeat sightings of the same one or two small 
groups.
Minke Whale (Balaenoptera acutorostrata)
    Minke whales are the smallest of the rorqual group of baleen 
whales. There are no population estimates for the North Pacific, 
although estimates have been made for some portions of Alaska. Zerbini 
et al. (2006) estimated the coastal population between Kenai Fjords and 
the Aleutian Islands at 1,233 animals. During Cook Inlet-wide aerial 
surveys conducted from 1993 to 2004, minke whales were encountered only 
twice (1998, 1999), both times off Anchor Point 16 mi northwest of 
Homer. A minke whale was also reported off Cape Starichkof in 2011 (A. 
Holmes, pers. comm.) and 2013 (E. Fernandez and C. Hesselbach, pers. 
comm.), suggesting this location is regularly used by minke whales, 
including during the winter. There are no records north of Cape 
Starichkof. However, 42 minke whales were recorded at Cosmopolitan 
State site #A-1 between May and August 2013 in patterns suggesting the 
presence of a small, yet conspicuous summer population (at least) 
within the Cosmopolitan State unit. All but three of the minke whales 
observed during the 2013 monitoring season were recorded over 984 ft 
(300 m) from the active drill rig.
    Minke whales have a very catholic diet feeding on preferred prey 
most abundant at a given time and location (Leatherwood and Reeves 
1983). In the southern hemisphere they feed largely on krill, while in 
the North Pacific they feed on schooling fish such as herring, 
sandlance, and walleye pollock (Reeves et al. 2002). There is no 
dietary information specific to Alaska although anecdotal observations 
of minke whales feeding on shoaling fish off Anchor Point have been 
reported to NMFS (Brad Smith, pers. comm.).
Dall's Porpoise (Phocoenoides dalli)
    Dall's porpoise are widely distributed throughout the North Pacific 
Ocean including Alaska, although they are not found in upper Cook Inlet 
and the shallower waters of the Bering, Chukchi, and Beaufort Seas 
(Allen and Angliss, 2014). The Alaskan population has been estimated at 
83,400 animals (Allen and Angliss, 2014), making it one of the more 
common cetaceans in the state. Dall's porpoise prefer the deep offshore 
and shelf slope waters where they feed largely on mesopelagic fish and 
squid, but also herring in more nearshore waters (Jefferson 2002). 
There is no diet information specific to Cook Inlet. Dall's porpoise 
have been observed in lower Cook Inlet, including Kachemak Bay and near 
Anchor Point (Glenn Johnson, pers. comm.), but sightings there are 
rare, as expected, given they prefer waters exceeding 180 meters deep. 
During 112 days of monitoring during the Cosmopolitan State #1 drilling 
operation between May and August 2013, 19 Dall's porpoise were recorded 
(all during the month of August), but none were observed in close 
proximity of the drill rig (i.e., they were greater than 853 ft [260 m 
away]).

 Pinnipeds

Harbor Seals (Phoca vitulina)
    Harbor seals inhabit the coastal and estuarine waters of Cook Inlet 
and are one of the more common marine mammal species in Alaskan waters. 
Harbor seals are non-migratory; their movements are associated with 
tides, weather, season, food availability, and reproduction. The major 
haulout sites for harbor seals are located in lower Cook Inlet, and 
their presence in the upper inlet coincides with seasonal runs of prey 
species. For example, harbor seals are commonly observed along the 
Susitna River and other tributaries along upper Cook Inlet during the 
eulachon and salmon migrations (NMFS, 2003). During aerial surveys of 
upper Cook Inlet in 2001, 2002, and 2003, harbor seals were observed 24 
to 96 km (15 to 60 mi) south-southwest of Anchorage at the Chickaloon, 
Little Susitna, Susitna, Ivan, McArthur, and Beluga Rivers (Rugh et 
al., 2005). Montgomery et al. (2007) recorded over 200 haulout sites in 
lower Cook Inlet alone. Montgomery et al. (2007) also found seals 
elsewhere in Cook Inlet to move in response to local steelhead and 
salmon runs. However, aerial surveys conducted in June 2013 for the 
proposed Susitna Dam project noted nearly 700 harbor seals in the 
Susitna Delta region (Alaska Energy Authority, 2013). During the marine 
mammal monitoring associated with the 2013 drilling activities at 
Cosmopolitan State, 77 harbor seals were recorded. Harbor seals may be 
encountered during BlueCrest's lower Cook Inlet proposed drilling 
program.
Steller Sea Lion (Eumetopias jubatus)
    The Western Stock of the Steller sea lion is defined as all 
populations west of longitude 144[deg] W. to the western end of the 
Aleutian Islands. The most recent estimate for this stock is 45,649 
animals (Allen and Angliss 2014), considerably less than that estimated 
140,000 animals in the 1950s (Merrick et al. 1987). Because of this 
dramatic decline, the stock was listed as threatened under ESA in 1990, 
and was relisted as endangered in 1997. Critical habitat was designated 
in 1993, and is defined as a 20-nautical-mile radius around all major 
rookeries and haulout sites. The 20-nautical-mile buffer was 
established based on telemetry data that indicated these sea lions 
concentrated their summer foraging effort within this distance of 
rookeries and haul outs.
    Steller sea lions inhabit lower Cook Inlet, especially in the 
vicinity of Shaw Island and Elizabeth Island (Nagahut Rocks) haulout 
sites (Rugh et al. 2005a), but are rarely seen in upper Cook Inlet 
(Nemeth et al. 2007). Of the 42 Steller sea lion groups recorded during 
Cook Inlet aerial surveys between 1993 and 2004, none were recorded 
north of Anchor Point and only one in the vicinity of Kachemak Bay 
(Rugh et al. 2005a). Marine mammal observers associated with 
Buccaneer's drilling project off Cape Starichkof did observe seven 
Steller sea lions during the summer of 2013 (Owl Ridge 2014).
    The upper reaches of Cook Inlet may not provide adequate foraging 
conditions for sea lions for establishing

[[Page 35556]]

a major haul out presence. Steller sea lions feed largely on walleye 
pollock (Theragra chalcogramma), salmon (Onchorhyncus spp.), and 
arrowtooth flounder (Atheresthes stomias) during the summer, and 
walleye pollock and Pacific cod (Gadus macrocephalus) during the winter 
(Sinclair and Zeppelin 2002), none which, except for salmon, are found 
in abundance in upper Cook Inlet (Nemeth et al. 2007). Small numbers of 
Steller sea lions are likely to be encountered during BlueCrest's 
planned operations in 2016 based on the observations of sea lions made 
at the lease site in 2013 (Owl Ridge 2014), but on of which was 
observed within 50m of the drill rig during the 2013 monitoring 
program.

Summary

    BlueCrest's application contains information on the status, 
distribution, seasonal distribution, and abundance of each of the 
species under NMFS jurisdiction mentioned in this document. Please 
refer to the application for that information (see ADDRESSES). 
Additional information can also be found in the NMFS Stock Assessment 
Reports (SAR). The Alaska 2014 SAR is available on the Internet at: 
https://www.nmfs.noaa.gov/pr/sars/pdf/ak2014_final.pdf.

Potential Effects of the Specified Activity on Marine Mammals

    This section includes a summary and discussion of the ways that the 
types of stressors associated with the specified activity (e.g., impact 
hammering of the drive pipe and VSP) has been observed to, or are 
thought to, impact marine mammals. The ``Estimated Take by Incidental 
Harassment'' section later in this document will include a quantitative 
analysis of the number of individuals that are expected to be taken by 
this activity. The ``Negligible Impact Analysis'' section will include 
the analysis of how this specific activity will impact marine mammals 
and will consider the content of this section, the ``Estimated Take by 
Incidental Harassment'' section, the ``Mitigation'' section, and the 
``Anticipated Effects on Marine Mammal Habitat'' section to draw 
conclusions regarding the likely impacts of this activity on the 
reproductive success or survivorship of individuals and from that on 
the affected marine mammal populations or stocks.
    The likely or possible impacts of the proposed drilling program in 
lower Cook Inlet on marine mammals could involve both non-acoustic and 
acoustic stressors. Potential non-acoustic stressors include the 
physical presence of the equipment and personnel. Petroleum development 
and associated activities introduce sound into the marine environment. 
Impacts to marine mammals are expected to primarily be acoustic in 
nature. Potential acoustic effects on marine mammals relate to impact 
hammering of drive pipe and the VSP airgun array.

Acoustic Impacts

    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Based 
on available behavioral data, audiograms have been derived using 
auditory evoked potentials, anatomical modeling, and other data, 
Southall et al. (2007) designate ``functional hearing groups'' for 
marine mammals and estimate the lower and upper frequencies of 
functional hearing of the groups. The functional groups and the 
associated frequencies are indicated below (though animals are less 
sensitive to sounds at the outer edge of their functional range and 
most sensitive to sounds of frequencies within a smaller range 
somewhere in the middle of their functional hearing range):
     Low frequency cetaceans (13 species of mysticetes): 
functional hearing is estimated to occur between approximately 7 Hz and 
25 kHz;
     Mid-frequency cetaceans (32 species of dolphins, six 
species of larger toothed whales, and 19 species of beaked and 
bottlenose whales): functional hearing is estimated to occur between 
approximately 150 Hz and 160 kHz;
     High frequency cetaceans (eight species of true porpoises, 
six species of river dolphins, Kogia, the franciscana, and four species 
of cephalorhynchids): functional hearing is estimated to occur between 
approximately 200 Hz and 180 kHz;
     Phocid pinnipeds in Water: functional hearing is estimated 
to occur between approximately 75 Hz and 100 kHz; and
     Otariid pinnipeds in Water: functional hearing is 
estimated to occur between approximately 100 Hz and 48 kHz.
    As mentioned previously in this document, nine marine mammal 
species (seven cetacean and two pinniped species) may occur in the 
drilling area of BlueCrest's lower Cook Inlet project. Of the seven 
cetacean species likely to occur in the proposed project area and for 
which take is requested, three are classified as low-frequency 
cetaceans (i.e., humpback, minke, and gray whales), two are classified 
as a mid-frequency cetacean (i.e., beluga and killer whales), and two 
are classified as high-frequency cetaceans (i.e., harbor and Dall's 
porpoises) (Southall et al., 2007). A species' functional hearing group 
is a consideration when we analyze the effects of exposure to sound on 
marine mammals.
1. Tolerance
    Numerous studies have shown that underwater sounds from industry 
activities are often readily detectable by marine mammals in the water 
at distances of many kilometers. Numerous studies have also shown that 
marine mammals at distances more than a few kilometers away often show 
no apparent response to industry activities of various types (Miller et 
al., 2005; Bain and Williams, 2006). This is often true even in cases 
when the sounds must be readily audible to the animals based on 
measured received levels and the hearing sensitivity of that mammal 
group. Although various baleen whales, toothed whales, and (less 
frequently) pinnipeds have been shown to react behaviorally to 
underwater sound such as airgun pulses or vessels under some 
conditions, at other times mammals of all three types have shown no 
overt reactions (e.g., Malme et al., 1986; Richardson et al., 1995a; 
Madsen and Mohl, 2000; Croll et al., 2001; Jacobs and Terhune, 2002; 
Madsen et al., 2002; Miller et al., 2005). Weir (2008) observed marine 
mammal responses to seismic pulses from a 24 airgun array firing a 
total volume of either 5,085 in\3\ or 3,147 in\3\ in Angolan waters 
between August 2004 and May 2005. Weir recorded a total of 207 
sightings of humpback whales (n = 66), sperm whales (n = 124), and 
Atlantic spotted dolphins (n = 17) and reported that there were no 
significant differences in encounter rates (sightings/hr) for humpback 
and sperm whales according to the airgun array's operational status 
(i.e., active versus silent). The airgun arrays used in the Weir (2008) 
study were much larger than the array proposed for use during the 
limited VSP (total discharge volumes of 600 to 880 in\3\ for 1 to 2 
days). In general, pinnipeds and small odontocetes seem to be more 
tolerant of exposure to some types of underwater sound than are baleen 
whales. Richardson et al. (1995a) found that vessel noise does not seem 
to strongly affect pinnipeds that are already in the water. Richardson 
et al. (1995a) went on to explain that seals on haul-outs sometimes 
respond strongly to the presence of vessels and at other times appear 
to show considerable tolerance of vessels.

[[Page 35557]]

2. Masking
    Masking is the obscuring of sounds of interest by other sounds, 
often at similar frequencies. Marine mammals use acoustic signals for a 
variety of purposes, which differ among species, but include 
communication between individuals, navigation, foraging, reproduction, 
avoiding predators, and learning about their environment (Erbe and 
Farmer, 2000; Tyack, 2000). Masking, or auditory interference, 
generally occurs when sounds in the environment are louder than, and of 
a similar frequency as, auditory signals an animal is trying to 
receive. Masking is a phenomenon that affects animals that are trying 
to receive acoustic information about their environment, including 
sounds from other members of their species, predators, prey, and sounds 
that allow them to orient in their environment. Masking these acoustic 
signals can disturb the behavior of individual animals, groups of 
animals, or entire populations in situations where the temporal and 
spatial scope of the masking activities is extensive.
    Masking occurs when anthropogenic sounds and signals (that the 
animal utilizes) overlap at both spectral and temporal scales. The 
sounds generated by the proposed equipment for the drilling program 
will consist of low frequency sources (most under 500 Hz). Lower 
frequency man-made sounds are more likely to affect detection of 
communication calls of low-frequency specialists and other potentially 
important natural sounds such as surf and prey noise. There is less 
concern regarding masking of conspecific vocalizations near the jack-up 
rig during drilling operations, as the species most likely to be found 
in the vicinity are mid- to high-frequency cetaceans or pinnipeds and 
not low-frequency cetaceans. Additionally, masking is not expected to 
be a concern from airgun usage due to the brief duration of use (less 
than a day to up to 2 days) and the low-frequency sounds that are 
produced by the airguns. However, at long distances (over tens of 
kilometers away), due to multipath propagation and reverberation, the 
durations of airgun pulses can be ``stretched'' to seconds with long 
decays (Madsen et al., 2006), although the intensity of the sound is 
greatly reduced.
    The ``stretching'' of sound described above could affect 
communication signals used by low frequency mysticetes when they occur 
near the noise band and thus reduce the communication space of animals 
(e.g., Clark et al., 2009) and cause increased stress levels (e.g., 
Foote et al., 2004; Holt et al., 2009); however, only low numbers of 
baleen whales are expected to occur within the proposed action area. 
Marine mammals are thought to sometimes be able to compensate for 
masking by adjusting their acoustic behavior by shifting call 
frequencies, and/or increasing call volume and vocalization rates. For 
example, blue whales are found to increase call rates when exposed to 
seismic survey noise in the St. Lawrence Estuary (Di Iorio and Clark, 
2010). The North Atlantic right whales (Eubalaena glacialis) exposed to 
high shipping noise increase call frequency (Parks et al., 2007), while 
some humpback whales respond to low-frequency active sonar playbacks by 
increasing song length (Miller el al., 2000). Additionally, beluga 
whales have been known to change their vocalizations in the presence of 
high background noise possibly to avoid masking calls (Au et al., 1985; 
Lesage et al., 1999; Scheifele et al., 2005). Although some degree of 
masking is inevitable when high levels of manmade broadband sounds are 
introduced into the sea, marine mammals have evolved systems and 
behavior that function to reduce the impacts of masking. Structured 
signals, such as the echolocation click sequences of small toothed 
whales, may be readily detected even in the presence of strong 
background noise because their frequency content and temporal features 
usually differ strongly from those of the background noise (Au and 
Moore, 1988, 1990). The components of background noise that are similar 
in frequency to the sound signal in question primarily determine the 
degree of masking of that signal.
    Redundancy and context can also facilitate detection of weak 
signals. These phenomena may help marine mammals detect weak sounds in 
the presence of natural or manmade noise. Most masking studies in 
marine mammals present the test signal and the masking noise from the 
same direction. The sound localization abilities of marine mammals 
suggest that, if signal and noise come from different directions, 
masking would not be as severe as the usual types of masking studies 
might suggest (Richardson et al., 1995a). The dominant background noise 
may be highly directional if it comes from a particular anthropogenic 
source such as a ship or industrial site. Directional hearing may 
significantly reduce the masking effects of these sounds by improving 
the effective signal-to-noise ratio. In the cases of higher frequency 
hearing by the bottlenose dolphin, beluga whale, and killer whale, 
empirical evidence confirms that masking depends strongly on the 
relative directions of arrival of sound signals and the masking noise 
(Penner et al., 1986; Dubrovskiy, 1990; Bain et al., 1993; Bain and 
Dahlheim, 1994). Toothed whales, and probably other marine mammals as 
well, have additional capabilities besides directional hearing that can 
facilitate detection of sounds in the presence of background noise. 
There is evidence that some toothed whales can shift the dominant 
frequencies of their echolocation signals from a frequency range with a 
lot of ambient noise toward frequencies with less noise (Au et al., 
1974, 1985; Moore and Pawloski, 1990; Thomas and Turl, 1990; Romanenko 
and Kitain, 1992; Lesage et al., 1999). A few marine mammal species are 
known to increase the source levels or alter the frequency of their 
calls in the presence of elevated sound levels (Dahlheim, 1987; Au, 
1993; Lesage et al., 1993, 1999; Terhune, 1999; Foote et al., 2004; 
Parks et al., 2007, 2009; Di Iorio and Clark, 2009; Holt et al., 2009).
    These data demonstrating adaptations for reduced masking pertain 
mainly to the very high frequency echolocation signals of toothed 
whales. There is less information about the existence of corresponding 
mechanisms at moderate or low frequencies or in other types of marine 
mammals. For example, Zaitseva et al. (1980) found that, for the 
bottlenose dolphin, the angular separation between a sound source and a 
masking noise source had little effect on the degree of masking when 
the sound frequency was 18 kHz, in contrast to the pronounced effect at 
higher frequencies. Directional hearing has been demonstrated at 
frequencies as low as 0.5-2 kHz in several marine mammals, including 
killer whales (Richardson et al., 1995a). This ability may be useful in 
reducing masking at these frequencies. In summary, high levels of sound 
generated by anthropogenic activities may act to mask the detection of 
weaker biologically important sounds by some marine mammals. This 
masking may be more prominent for lower frequencies. For higher 
frequencies, such as that used in echolocation by toothed whales, 
several mechanisms are available that may allow them to reduce the 
effects of such masking.
3. Behavioral Disturbance
    Behavioral responses to sound are highly variable and context-
specific. Many different variables can influence an animal's perception 
of and response to (in both nature and magnitude) an acoustic event. An 
animal's prior

[[Page 35558]]

experience with a sound or sound source affects whether it is less 
likely (habituation) or more likely (sensitization) to respond to 
certain sounds in the future (animals can also be innately pre-disposed 
to respond to certain sounds in certain ways; Southall et al., 2007). 
Related to the sound itself, the perceived nearness of the sound, 
bearing of the sound (approaching vs. retreating), similarity of a 
sound to biologically relevant sounds in the animal's environment 
(i.e., calls of predators, prey, or conspecifics), and familiarity of 
the sound may affect the way an animal responds to the sound (Southall 
et al., 2007). Individuals (of different age, gender, reproductive 
status, etc.) among most populations will have variable hearing 
capabilities and differing behavioral sensitivities to sounds that will 
be affected by prior conditioning, experience, and current activities 
of those individuals. Often, specific acoustic features of the sound 
and contextual variables (i.e., proximity, duration, or recurrence of 
the sound or the current behavior that the marine mammal is engaged in 
or its prior experience), as well as entirely separate factors such as 
the physical presence of a nearby vessel, may be more relevant to the 
animal's response than the received level alone.
    Exposure of marine mammals to sound sources can result in (but is 
not limited to) no response or any of the following observable 
responses: Increased alertness; orientation or attraction to a sound 
source; vocal modifications; cessation of feeding; cessation of social 
interaction; alteration of movement or diving behavior; avoidance; 
habitat abandonment (temporary or permanent); and, in severe cases, 
panic, flight, stampede, or stranding, potentially resulting in death 
(Southall et al., 2007). The biological significance of many of these 
behavioral disturbances is difficult to predict.
    The following sub-sections provide examples of the variability in 
behavioral responses that could be expected given the different 
sensitivities of marine mammal species to sound.
    Baleen Whales--Richardson et al. (1995b) reported changes in 
surfacing and respiration behavior and the occurrence of turns during 
surfacing in bowhead whales exposed to playback of underwater sound 
from drilling activities. These behavioral effects were localized and 
occurred at distances up to 1.2-2.5 mi (2-4 km).
    Richardson et al. (2008) reported a slight change in the 
distribution of bowhead whale calls in response to operational sounds 
on BP's Northstar Island. The southern edge of the call distribution 
ranged from 0.47 to 1.46 mi (0.76 to 2.35 km) farther offshore, 
apparently in response to industrial sound levels. However, this result 
was only achieved after intensive statistical analyses, and it is not 
clear that this represented a biologically significant effect.
    Richardson et al. (1995a) and Moore and Clarke (2002) reviewed a 
few studies that observed responses of gray whales to aircraft. Cow-
calf pairs were quite sensitive to a turboprop survey flown at 1,000 ft 
(305 m) altitude on the Alaskan summering grounds. In that survey, 
adults were seen swimming over the calf, or the calf swam under the 
adult (Ljungblad et al., 1983, cited in Richardson et al., 1995a and 
Moore and Clarke, 2002). However, when the same aircraft circled for 
more than 10 minutes at 1,050 ft (320 m) altitude over a group of 
mating gray whales, no reactions were observed (Ljungblad et al., 1987, 
cited in Moore and Clarke, 2002). Malme et al. (1984, cited in 
Richardson et al., 1995a and Moore and Clarke, 2002) conducted playback 
experiments on migrating gray whales. They exposed the animals to 
underwater noise recorded from a Bell 212 helicopter (estimated 
altitude = 328 ft [100 m]), at an average of three simulated passes per 
minute. The authors observed that whales changed their swimming course 
and sometimes slowed down in response to the playback sound but 
proceeded to migrate past the transducer. Migrating gray whales did not 
react overtly to a Bell 212 helicopter at greater than 1,394 ft (425 m) 
altitude, occasionally reacted when the helicopter was at 1,000-1,198 
ft (305-365 m), and usually reacted when it was below 825 ft (250 m; 
Southwest Research Associates, 1988, cited in Richardson et al., 1995a 
and Moore and Clarke, 2002). Reactions noted in that study included 
abrupt turns or dives or both. Green et al. (1992, cited in Richardson 
et al., 1995a) observed that migrating gray whales rarely exhibited 
noticeable reactions to a straight-line overflight by a Twin Otter at 
197 ft (60 m) altitude. Overflights are likely to have little or no 
disturbance effects on baleen whales. Any disturbance that may occur 
would likely be temporary and localized.
    Southall et al. (2007, Appendix C) reviewed a number of papers 
describing the responses of marine mammals to non-pulsed sound, such as 
that produced during drilling operations. In general, little or no 
response was observed in animals exposed at received levels from 90-120 
dB re 1 [micro]Pa (rms). Probability of avoidance and other behavioral 
effects increased when received levels were from 120-160 dB re 1 
[micro]Pa (rms). Some of the relevant reviews contained in Southall et 
al. (2007) are summarized next.
    Baker et al. (1982) reported some avoidance by humpback whales to 
vessel noise when received levels were 110-120 dB (rms) and clear 
avoidance at 120-140 dB (sound measurements were not provided by Baker 
but were based on measurements of identical vessels by Miles and Malme, 
1983).
    Malme et al. (1983, 1984) used playbacks of sounds from helicopter 
overflight and drilling rigs and platforms to study behavioral effects 
on migrating gray whales. Received levels exceeding 120 dB induced 
avoidance reactions. Malme et al. (1984) calculated 10%, 50%, and 90% 
probabilities of gray whale avoidance reactions at received levels of 
110, 120, and 130 dB, respectively. Malme et al. (1986) observed the 
behavior of feeding gray whales during four experimental playbacks of 
drilling sounds (50 to 315 Hz; 21-min overall duration and 10% duty 
cycle; source levels of 156-162 dB). In two cases for received levels 
of 100-110 dB, no behavioral reaction was observed. However, avoidance 
behavior was observed in two cases where received levels were 110-120 
dB.
    Richardson et al. (1990) performed 12 playback experiments in which 
bowhead whales in the Alaskan Arctic were exposed to drilling sounds. 
Whales generally did not respond to exposures in the 100 to 130 dB 
range, although there was some indication of minor behavioral changes 
in several instances.
    McCauley et al. (1996) reported several cases of humpback whales 
responding to vessels in Hervey Bay, Australia. Results indicated clear 
avoidance at received levels between 118 to 124 dB in three cases for 
which response and received levels were observed/measured.
    Palka and Hammond (2001) analyzed line transect census data in 
which the orientation and distance off transect line were reported for 
large numbers of minke whales. The authors developed a method to 
account for effects of animal movement in response to sighting 
platforms. Minor changes in locomotion speed, direction, and/or diving 
profile were reported at ranges from 1,847 to 2,352 ft (563 to 717 m) 
at received levels of 110 to 120 dB.
    Biassoni et al. (2000) and Miller et al. (2000) reported behavioral 
observations for humpback whales exposed to a low-frequency sonar 
stimulus (160- to 330-Hz frequency band; 42-s tonal signal repeated 
every 6 min; source levels 170 to 200 dB) during playback experiments. 
Exposure to measured received levels

[[Page 35559]]

ranging from 120 to 150 dB resulted in variability in humpback singing 
behavior. Croll et al. (2001) investigated responses of foraging fin 
and blue whales to the same low frequency active sonar stimulus off 
southern California. Playbacks and control intervals with no 
transmission were used to investigate behavior and distribution on time 
scales of several weeks and spatial scales of tens of kilometers. The 
general conclusion was that whales remained feeding within a region for 
which 12 to 30 percent of exposures exceeded 140 dB.
    Frankel and Clark (1998) conducted playback experiments with 
wintering humpback whales using a single speaker producing a low-
frequency ``M-sequence'' (sine wave with multiple-phase reversals) 
signal in the 60 to 90 Hz band with output of 172 dB at 1 m. For 11 
playbacks, exposures were between 120 and 130 dB re 1 [micro]Pa (rms) 
and included sufficient information regarding individual responses. 
During eight of the trials, there were no measurable differences in 
tracks or bearings relative to control conditions, whereas on three 
occasions, whales either moved slightly away from (n = 1) or towards (n 
= 2) the playback speaker during exposure. The presence of the source 
vessel itself had a greater effect than did the M-sequence playback.
    Finally, Nowacek et al. (2004) used controlled exposures to 
demonstrate behavioral reactions of northern right whales to various 
non-pulse sounds. Playback stimuli included ship noise, social sounds 
of conspecifics, and a complex, 18-min ``alert'' sound consisting of 
repetitions of three different artificial signals. Ten whales were 
tagged with calibrated instruments that measured received sound 
characteristics and concurrent animal movements in three dimensions. 
Five out of six exposed whales reacted strongly to alert signals at 
measured received levels between 130 and 150 dB (i.e., ceased foraging 
and swam rapidly to the surface). Two of these individuals were not 
exposed to ship noise, and the other four were exposed to both stimuli. 
These whales reacted mildly to conspecific signals. Seven whales, 
including the four exposed to the alert stimulus, had no measurable 
response to either ship sounds or actual vessel noise.
    Baleen whale responses to pulsed sound (e.g., seismic airguns) have 
been studied more thoroughly than responses to continuous sound (e.g., 
drill rigs). Baleen whales generally tend to avoid operating airguns, 
but avoidance radii are quite variable. Whales are often reported to 
show no overt reactions to pulses from large arrays of airguns at 
distances beyond a few kilometers, even though the airgun pulses remain 
well above ambient noise levels out to much greater distances (Miller 
et al., 2005). However, baleen whales exposed to strong noise pulses 
often react by deviating from their normal migration route (Richardson 
et al., 1999). Migrating gray and bowhead whales were observed avoiding 
the sound source by displacing their migration route to varying degrees 
but within the natural boundaries of the migration corridors (Schick 
and Urban, 2000; Richardson et al., 1999; Malme et al., 1983). Baleen 
whale responses to pulsed sound however may depend on the type of 
activity in which the whales are engaged. Some evidence suggests that 
feeding bowhead whales may be more tolerant of underwater sound than 
migrating bowheads (Miller et al., 2005; Lyons et al., 2009; Christie 
et al., 2010).
    Results of studies of gray, bowhead, and humpback whales have 
determined that received levels of pulses in the 160-170 dB re 1 
[micro]Pa rms range seem to cause obvious avoidance behavior in a 
substantial fraction of the animals exposed. In many areas, seismic 
pulses from large arrays of airguns diminish to those levels at 
distances ranging from 2.8-9 mi (4.5-14.5 km) from the source. For the 
much smaller airgun array used during the VSP survey (total discharge 
volume between 600 and 880 in\3\), the distance to a received level of 
160 dB re 1 [micro]Pa rms is estimated to be 1.53 mi (2.47 km). Baleen 
whales within those sound isopleths may show avoidance or other strong 
disturbance reactions to the airgun array.
    Malme et al. (1986, 1988) studied the responses of feeding eastern 
gray whales to pulses from a single 100 in\3\ airgun off St. Lawrence 
Island in the northern Bering Sea. They estimated, based on small 
sample sizes, that 50% of feeding gray whales ceased feeding at an 
average received pressure level of 173 dB re 1 [micro]Pa on an 
(approximate) rms basis, and that 10% of feeding whales interrupted 
feeding at received levels of 163 dB. Those findings were generally 
consistent with the results of experiments conducted on larger numbers 
of gray whales that were migrating along the California coast and on 
observations of the distribution of feeding Western Pacific gray whales 
off Sakhalin Island, Russia, during a seismic survey (Yazvenko et al., 
2007).
    Data on short-term reactions (or lack of reactions) of cetaceans to 
impulsive noises do not necessarily provide information about long-term 
effects. While it is not certain whether impulsive noises affect 
reproductive rate or distribution and habitat use in subsequent days or 
years, certain species have continued to use areas ensonified by 
airguns and have continued to increase in number despite successive 
years of anthropogenic activity in the area. Behavioral responses to 
noise exposure are generally highly variable and context dependent 
(Wartzok et al. 2004). Travelling blue and fin whales (Balaenoptera 
physalus) exposed to seismic noise from airguns have been reported to 
stop emitting redundant songs (McDonald et al. 1995; Clark & Gagnon 
2006). By contrast, Iorio and Clark (2010) found increased production 
of transient, non-redundant calls of blue whales during seismic sparker 
operations. In any event, the brief exposures to sound pulses from the 
proposed airgun source (the airguns will only be fired for a few hours 
at a time over the course of 1 to 2 days) are highly unlikely to result 
in prolonged effects.
    Toothed Whales--Most toothed whales have their greatest hearing 
sensitivity at frequencies much higher than that of baleen whales and 
may be less responsive to low-frequency sound commonly associated with 
oil and gas industry exploratory drilling activities. Richardson et al. 
(1995b) reported that beluga whales did not show any apparent reaction 
to playback of underwater drilling sounds at distances greater than 
656-1,312 ft (200-400 m). Reactions included slowing down, milling, or 
reversal of course after which the whales continued past the projector, 
sometimes within 164-328 ft (50-100 m). The authors concluded (based on 
a small sample size) that the playback of drilling sounds had no 
biologically significant effects on migration routes of beluga whales 
migrating through pack ice and along the seaward side of the nearshore 
lead east of Point Barrow in spring.
    At least six of 17 groups of beluga whales appeared to alter their 
migration path in response to underwater playbacks of icebreaker sound 
(Richardson et al., 1995b). Received levels from the icebreaker 
playback were estimated at 78-84 dB in the \1/3\-octave band centered 
at 5,000 Hz, or 8-14 dB above ambient. If beluga whales reacted to an 
actual icebreaker at received levels of 80 dB, reactions would be 
expected to occur at distances on the order of 6.2 mi (10 km). Finley 
et al. (1990) also reported beluga avoidance of icebreaker activities 
in the Canadian High Arctic at distances of 22-31 mi (35-50 km). In 
addition to avoidance, changes in dive behavior and pod integrity were 
also noted. However,

[[Page 35560]]

no icebreakers will be used during this proposed program.
    Patenaude et al. (2002) reported changes in beluga whale diving and 
respiration behavior, and some whales veered away when a helicopter 
passed at <=820 ft (250 m) lateral distance at altitudes up to 492 ft 
(150 m). However, some belugas showed no reaction to the helicopter. 
Belugas appeared to show less response to fixed-wing aircraft than to 
helicopter overflights.
    In reviewing responses of cetaceans with best hearing in mid-
frequency ranges, which includes toothed whales, Southall et al. (2007) 
reported that combined field and laboratory data for mid-frequency 
cetaceans exposed to non-pulse sounds did not lead to a clear 
conclusion about received levels coincident with various behavioral 
responses. In some settings, individuals in the field showed profound 
(significant) behavioral responses to exposures from 90-120 dB, while 
others failed to exhibit such responses for exposure to received levels 
from 120-150 dB. Contextual variables other than exposure received 
level, and probable species differences, are the likely reasons for 
this variability. Context, including the fact that captive subjects 
were often directly reinforced with food for tolerating noise exposure, 
may also explain why there was great disparity in results from field 
and laboratory conditions--exposures in captive settings generally 
exceeded 170 dB before inducing behavioral responses. A summary of some 
of the relevant material reviewed by Southall et al. (2007) is next.
    Buckstaff (2004) reported elevated bottlenose dolphin (Tursiops 
trancatus) whistle rates with received levels from oncoming vessels in 
the 110 to 120 dB range in Sarasota Bay, Florida. These hearing 
thresholds were apparently lower than those reported by a researcher 
listening with towed hydrophones. Morisaka et al. (2005) compared 
whistles from three populations of Indo-Pacific bottlenose dolphins 
(Tursiops aduncus). One population was exposed to vessel noise with 
spectrum levels of approximately 85 dB/Hz in the 1- to 22-kHz band 
(broadband received levels approximately 128 dB) as opposed to 
approximately 65 dB/Hz in the same band (broadband received levels 
approximately 108 dB) for the other two sites. Dolphin whistles in the 
noisier environment had lower fundamental frequencies and less 
frequency modulation, suggesting a shift in sound parameters as a 
result of increased ambient noise.
    Morton and Symonds (2002) used census data on killer whales in 
British Columbia to evaluate avoidance of non-pulse acoustic harassment 
devices (AHDs). Avoidance ranges were about 2.5 mi (4 km). Also, there 
was a dramatic reduction in the number of days ``resident'' killer 
whales were sighted during AHD-active periods compared to pre- and 
post-exposure periods and a nearby control site.
    Monteiro-Neto et al. (2004) studied avoidance responses of tucuxi 
(Sotalia fluviatilis), a freshwater dolphin, to Dukane[supreg] Netmark 
acoustic deterrent devices. In a total of 30 exposure trials, 
approximately five groups each demonstrated significant avoidance 
compared to 20 ``pinger off'' and 55 ``no-pinger'' control trials over 
two quadrants of about 0.19 mi \2\ (0.5 km \2\). Estimated exposure 
received levels were approximately 115 dB.
    Awbrey and Stewart (1983) played back semi-submersible drillship 
sounds (source level: 163 dB) to belugas in Alaska. They reported 
avoidance reactions at 984 and 4,921 ft (300 and 1,500 m) and approach 
by groups at a distance of 2.2 mi (3.5 km; received levels were 
approximately 110 to 145 dB over these ranges assuming a 15 log R 
transmission loss). Similarly, Richardson et al. (1990) played back 
drilling platform sounds (source level: 163 dB) to belugas in Alaska. 
They conducted aerial observations of eight individuals among 
approximately 100 spread over an area several hundred meters to several 
kilometers from the sound source and found no obvious reactions. 
Moderate changes in movement were noted for three groups swimming 
within 656 ft (200 m) of the sound projector.
    Two studies deal with issues related to changes in marine mammal 
vocal behavior as a function of variable background noise levels. Foote 
et al. (2004) found increases in the duration of killer whale calls 
over the period 1977 to 2003, during which time vessel traffic in Puget 
Sound, and particularly whale-watching boats around the animals, 
increased dramatically. Scheifele et al. (2005) demonstrated that 
belugas in the St. Lawrence River increased the levels of their 
vocalizations as a function of the background noise level (the 
``Lombard Effect'').
    Several researchers conducting laboratory experiments on hearing 
and the effects of non-pulse sounds on hearing in mid-frequency 
cetaceans have reported concurrent behavioral responses. Nachtigall et 
al. (2003) reported that noise exposures up to 179 dB and 55-min 
duration affected the trained behaviors of a bottlenose dolphin 
participating in a temporary threshold shift (TTS) experiment. Finneran 
and Schlundt (2004) provided a detailed, comprehensive analysis of the 
behavioral responses of belugas and bottlenose dolphins to 1-s tones 
(received levels 160 to 202 dB) in the context of TTS experiments. 
Romano et al. (2004) investigated the physiological responses of a 
bottlenose dolphin and a beluga exposed to these tonal exposures and 
demonstrated a decrease in blood cortisol levels during a series of 
exposures between 130 and 201 dB. Collectively, the laboratory 
observations suggested the onset of a behavioral response at higher 
received levels than did field studies. The differences were likely 
related to the very different conditions and contextual variables 
between untrained, free-ranging individuals vs. laboratory subjects 
that were rewarded with food for tolerating noise exposure.
    Seismic operators and marine mammal observers sometimes see 
dolphins and other small toothed whales near operating airgun arrays, 
but, in general, there seems to be a tendency for most delphinids to 
show some limited avoidance of seismic vessels operating large airgun 
systems. However, some dolphins seem to be attracted to the seismic 
vessel and floats, and some ride the bow wave of the seismic vessel 
even when large arrays of airguns are firing. Nonetheless, there have 
been indications that small toothed whales sometimes move away or 
maintain a somewhat greater distance from the vessel when a large array 
of airguns is operating than when it is silent (e.g., Goold, 1996a,b,c; 
Calambokidis and Osmek, 1998; Stone, 2003). The beluga may be a species 
that (at least at times) shows long-distance avoidance of seismic 
vessels. Aerial surveys during seismic operations in the southeastern 
Beaufort Sea recorded much lower sighting rates of beluga whales within 
6.2-12.4 mi (10-20 km) of an active seismic vessel. These results were 
consistent with the low number of beluga sightings reported by 
observers aboard the seismic vessel, suggesting that some belugas might 
be avoiding the seismic operations at distances of 6.2-12.4 mi (10-20 
km) (Miller et al., 2005).
    Observers stationed on seismic vessels operating off the United 
Kingdom from 1997-2000 have provided data on the occurrence and 
behavior of various toothed whales exposed to seismic pulses (Stone, 
2003; Gordon et al., 2004). Killer whales were found to be 
significantly farther from large airgun arrays during periods of 
shooting compared with periods of no

[[Page 35561]]

shooting. The displacement of the median distance from the array was 
approximately 0.5 km (0.3 mi) or more. Killer whales also appear to be 
more tolerant of seismic shooting in deeper water.
    Captive bottlenose dolphins and beluga whales exhibit changes in 
behavior when exposed to strong pulsed sounds similar in duration to 
those typically used in seismic surveys (Finneran et al., 2002, 2005). 
However, the animals tolerated high received levels of sound (p-p level 
>200 dB re 1 [mu]Pa) before exhibiting aversive behaviors.
    Pinnipeds--Pinnipeds generally seem to be less responsive to 
exposure to industrial sound than most cetaceans. Pinniped responses to 
underwater sound from some types of industrial activities such as 
seismic exploration appear to be temporary and localized (Harris et 
al., 2001; Reiser et al., 2009).
    Southall et al. (2007) reviewed literature describing responses of 
pinnipeds to non-pulsed sound and reported that the limited data 
suggest exposures between approximately 90 and 140 dB generally do not 
appear to induce strong behavioral responses in pinnipeds exposed to 
non-pulse sounds in water; no data exist regarding exposures at higher 
levels. It is important to note that among these studies, there are 
some apparent differences in responses between field and laboratory 
conditions. In contrast to the mid-frequency odontocetes, captive 
pinnipeds responded more strongly at lower levels than did animals in 
the field. Again, contextual issues are the likely cause of this 
difference.
    Jacobs and Terhune (2002) observed harbor seal reactions to 
Acoustic Harassment Devices (AHD) (source level in this study was 172 
dB) deployed around aquaculture sites. Seals were generally 
unresponsive to sounds from the AHDs. During two specific events, 
individuals came within 141 and 144 ft (43 and 44 m) of active AHDs and 
failed to demonstrate any measurable behavioral response; estimated 
received levels based on the measures given were approximately 120 to 
130 dB.
    Costa et al. (2003) measured received noise levels from an Acoustic 
Thermometry of Ocean Climate (ATOC) program sound source off northern 
California using acoustic data loggers placed on translocated elephant 
seals. Subjects were captured on land, transported to sea, instrumented 
with archival acoustic tags, and released such that their transit would 
lead them near an active ATOC source (at 939-m depth; 75-Hz signal with 
37.5-Hz bandwidth; 195 dB maximum source level, ramped up from 165 dB 
over 20 min) on their return to a haul-out site. Received exposure 
levels of the ATOC source for experimental subjects averaged 128 dB 
(range 118 to 137) in the 60- to 90-Hz band. None of the instrumented 
animals terminated dives or radically altered behavior upon exposure, 
but some statistically significant changes in diving parameters were 
documented in nine individuals. Translocated northern elephant seals 
exposed to this particular non-pulse source began to demonstrate subtle 
behavioral changes at exposure to received levels of approximately 120 
to 140 dB.
    Kastelein et al. (2006) exposed nine captive harbor seals in an 
approximately 82 x 98 ft (25 x 30 m) enclosure to non-pulse sounds used 
in underwater data communication systems (similar to acoustic modems). 
Test signals were frequency modulated tones, sweeps, and bands of noise 
with fundamental frequencies between 8 and 16 kHz; 128 to 130 [3] dB source levels; 1- to 2-s duration [60-80 percent duty 
cycle]; or 100 percent duty cycle. They recorded seal positions and the 
mean number of individual surfacing behaviors during control periods 
(no exposure), before exposure, and in 15-min experimental sessions (n 
= 7 exposures for each sound type). Seals generally swam away from each 
source at received levels of approximately 107 dB, avoiding it by 
approximately 16 ft (5 m), although they did not haul out of the water 
or change surfacing behavior. Seal reactions did not appear to wane 
over repeated exposure (i.e., there was no obvious habituation), and 
the colony of seals generally returned to baseline conditions following 
exposure. The seals were not reinforced with food for remaining in the 
sound field.
    Potential effects to pinnipeds from aircraft activity could involve 
both acoustic and non-acoustic effects. It is uncertain if the seals 
react to the sound of the helicopter or to its physical presence flying 
overhead. Typical reactions of hauled out pinnipeds to aircraft that 
have been observed include looking up at the aircraft, moving on the 
ice or land, entering a breathing hole or crack in the ice, or entering 
the water. Ice seals hauled out on the ice have been observed diving 
into the water when approached by a low-flying aircraft or helicopter 
(Burns and Harbo, 1972, cited in Richardson et al., 1995a; Burns and 
Frost, 1979, cited in Richardson et al., 1995a). Richardson et al. 
(1995a) note that responses can vary based on differences in aircraft 
type, altitude, and flight pattern.
    Blackwell et al. (2004a) observed 12 ringed seals during low-
altitude overflights of a Bell 212 helicopter at Northstar in June and 
July 2000 (nine observations took place concurrent with pipe-driving 
activities). One seal showed no reaction to the aircraft while the 
remaining 11 (92%) reacted, either by looking at the helicopter (n = 
10) or by departing from their basking site (n = 1). Blackwell et al. 
(2004a) concluded that none of the reactions to helicopters were strong 
or long lasting, and that seals near Northstar in June and July 2000 
probably had habituated to industrial sounds and visible activities 
that had occurred often during the preceding winter and spring. There 
have been few systematic studies of pinniped reactions to aircraft 
overflights, and most of the available data concern pinnipeds hauled 
out on land or ice rather than pinnipeds in the water (Richardson et 
al., 1995a; Born et al., 1999).
    Reactions of harbor seals to the simulated sound of a 2-megawatt 
wind power generator were measured by Koschinski et al. (2003). Harbor 
seals surfaced significantly further away from the sound source when it 
was active and did not approach the sound source as closely. The device 
used in that study produced sounds in the frequency range of 30 to 800 
Hz, with peak source levels of 128 dB at 1 m at the 80- and 160-Hz 
frequencies.
    Pinnipeds are not likely to show a strong avoidance reaction to the 
airgun sources proposed for use. Visual monitoring from seismic vessels 
has shown only slight (if any) avoidance of airguns by pinnipeds and 
only slight (if any) changes in behavior. Monitoring work in the 
Alaskan Beaufort Sea during 1996-2001 provided considerable information 
regarding the behavior of Arctic ice seals exposed to seismic pulses 
(Harris et al., 2001; Moulton and Lawson, 2002). These seismic projects 
usually involved arrays of 6 to 16 airguns with total volumes of 560 to 
1,500 in\3\. The combined results suggest that some seals avoid the 
immediate area around seismic vessels. In most survey years, ringed 
seal sightings tended to be farther away from the seismic vessel when 
the airguns were operating than when they were not (Moulton and Lawson, 
2002). However, these avoidance movements were relatively small, on the 
order of 100 m (328 ft) to a few hundreds of meters, and many seals 
remained within 100-200 m (328-656 ft) of the trackline as the 
operating airgun array passed by. Seal sighting rates at the water 
surface were lower during airgun array operations than during no-airgun 
periods in each survey year except 1997. Similarly, seals are often 
very tolerant of pulsed sounds

[[Page 35562]]

from seal-scaring devices (Mate and Harvey, 1987; Jefferson and Curry, 
1994; Richardson et al., 1995a). However, initial telemetry work 
suggests that avoidance and other behavioral reactions by two other 
species of seals to small airgun sources may at times be stronger than 
evident to date from visual studies of pinniped reactions to airguns 
(Thompson et al., 1998). Even if reactions of the species occurring in 
the present study area are as strong as those evident in the telemetry 
study, reactions are expected to be confined to relatively small 
distances and durations.
4. Threshold Shift (Noise-Induced Loss of Hearing)
    When animals exhibit reduced hearing sensitivity (i.e., sounds must 
be louder for an animal to detect them) following exposure to an 
intense sound or sound for long duration, it is referred to as a noise-
induced threshold shift (TS). An animal can experience temporary 
threshold shift (TTS) or permanent threshold shift (PTS). TTS can last 
from minutes or hours to days (i.e., there is complete recovery), can 
occur in specific frequency ranges (i.e., an animal might only have a 
temporary loss of hearing sensitivity between the frequencies of 1 and 
10 kHz), and can be of varying amounts (for example, an animal's 
hearing sensitivity might be reduced initially by only 6 dB or reduced 
by 30 dB). PTS is permanent, but some recovery is possible. PTS can 
also occur in a specific frequency range and amount as mentioned above 
for TTS.
    The following physiological mechanisms are thought to play a role 
in inducing auditory TS: Effects to sensory hair cells in the inner ear 
that reduce their sensitivity, modification of the chemical environment 
within the sensory cells, residual muscular activity in the middle ear, 
displacement of certain inner ear membranes, increased blood flow, and 
post-stimulatory reduction in both efferent and sensory neural output 
(Southall et al., 2007). The amplitude, duration, frequency, temporal 
pattern, and energy distribution of sound exposure all can affect the 
amount of associated TS and the frequency range in which it occurs. As 
amplitude and duration of sound exposure increase, so, generally, does 
the amount of TS, along with the recovery time. For intermittent 
sounds, less TS could occur than compared to a continuous exposure with 
the same energy (some recovery could occur between intermittent 
exposures depending on the duty cycle between sounds) (Kryter et al., 
1966; Ward, 1997). For example, one short but loud (higher SPL) sound 
exposure may induce the same impairment as one longer but softer sound, 
which in turn may cause more impairment than a series of several 
intermittent softer sounds with the same total energy (Ward, 1997). 
Additionally, though TTS is temporary, prolonged exposure to sounds 
strong enough to elicit TTS, or shorter-term exposure to sound levels 
well above the TTS threshold, can cause PTS, at least in terrestrial 
mammals (Kryter, 1985). However, in the case of the proposed drilling 
program, animals are not expected to be exposed to levels high enough 
or durations long enough to result in PTS, as described in detail in 
the paragraphs below.
    PTS is considered auditory injury (Southall et al., 2007). 
Irreparable damage to the inner or outer cochlear hair cells may cause 
PTS; however, other mechanisms are also involved, such as exceeding the 
elastic limits of certain tissues and membranes in the middle and inner 
ears and resultant changes in the chemical composition of the inner ear 
fluids (Southall et al., 2007).
    Although the published body of scientific literature contains 
numerous theoretical studies and discussion papers on hearing 
impairments that can occur with exposure to a loud sound, only a few 
studies provide empirical information on the levels at which noise-
induced loss in hearing sensitivity occurs in nonhuman animals. For 
marine mammals, published data are limited to the captive bottlenose 
dolphin, beluga, harbor porpoise, and Yangtze finless porpoise 
(Finneran et al., 2000, 2002b, 2003, 2005a, 2007, 2010a, 2010b; 
Finneran and Schlundt, 2010; Lucke et al., 2009; Mooney et al., 2009a, 
2009b; Popov et al., 2011a, 2011b; Kastelein et al., 2012a; Schlundt et 
al., 2000; Nachtigall et al., 2003, 2004). For pinnipeds in water, data 
are limited to measurements of TTS in harbor seals, an elephant seal, 
and California sea lions (Kastak et al., 1999, 2005; Kastelein et al., 
2012b).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
(similar to those discussed in auditory masking, below). For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that occurs 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so we can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
    Given the higher level of sound necessary to cause PTS as compared 
with TTS, it is considerably less likely that PTS would occur during 
the proposed drilling program in Cook Inlet due to the relatively short 
duration of activities producing these higher level sounds in 
combination with mitigation and monitoring efforts to avoid such 
effects.
5. Non-Auditory Physical Effects
    Non-auditory physical effects might occur in marine mammals exposed 
to strong underwater sound. Possible types of non-auditory 
physiological effects or injuries that theoretically might occur in 
mammals close to a strong sound source include stress, neurological 
effects, bubble formation, and other types of organ or tissue damage. 
Some marine mammal species (i.e., beaked whales) may be especially 
susceptible to injury and/or stranding when exposed to strong pulsed 
sounds.
    Classic stress responses begin when an animal's central nervous 
system perceives a potential threat to its homeostasis. That perception 
triggers stress responses regardless of whether a stimulus actually 
threatens the animal; the mere perception of a threat is sufficient to 
trigger a stress response (Moberg, 2000; Sapolsky et al., 2005; Seyle, 
1950). Once an animal's central nervous system perceives a threat, it 
mounts a biological response or defense that consists of a combination 
of the four general biological defense responses: Behavioral responses; 
autonomic nervous system responses; neuroendocrine responses; or immune 
responses.
    In the case of many stressors, an animal's first and most 
economical (in terms of biotic costs) response is behavioral avoidance 
of the potential stressor or avoidance of continued

[[Page 35563]]

exposure to a stressor. An animal's second line of defense to stressors 
involves the sympathetic part of the autonomic nervous system and the 
classical ``fight or flight'' response, which includes the 
cardiovascular system, the gastrointestinal system, the exocrine 
glands, and the adrenal medulla to produce changes in heart rate, blood 
pressure, and gastrointestinal activity that humans commonly associate 
with ``stress.'' These responses have a relatively short duration and 
may or may not have significant long-term effects on an animal's 
welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine or sympathetic nervous systems; the system that has 
received the most study has been the hypothalmus-pituitary-adrenal 
system (also known as the HPA axis in mammals or the hypothalamus-
pituitary-interrenal axis in fish and some reptiles). Unlike stress 
responses associated with the autonomic nervous system, virtually all 
neuroendocrine functions that are affected by stress--including immune 
competence, reproduction, metabolism, and behavior--are regulated by 
pituitary hormones. Stress-induced changes in the secretion of 
pituitary hormones have been implicated in failed reproduction (Moberg, 
1987; Rivier, 1995), altered metabolism (Elasser et al., 2000), reduced 
immune competence (Blecha, 2000), and behavioral disturbance. Increases 
in the circulation of glucocorticosteroids (cortisol, corticosterone, 
and aldosterone in marine mammals; see Romano et al., 2004) have been 
equated with stress for many years.
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and distress is the biotic cost 
of the response. During a stress response, an animal uses glycogen 
stores that can be quickly replenished once the stress is alleviated. 
In such circumstances, the cost of the stress response would not pose a 
risk to the animal's welfare. However, when an animal does not have 
sufficient energy reserves to satisfy the energetic costs of a stress 
response, energy resources must be diverted from other biotic 
functions, which impair those functions that experience the diversion. 
For example, when mounting a stress response diverts energy away from 
growth in young animals, those animals may experience stunted growth. 
When mounting a stress response diverts energy from a fetus, an 
animal's reproductive success and fitness will suffer. In these cases, 
the animals will have entered a pre-pathological or pathological state 
which is called ``distress'' (sensu Seyle, 1950) or ``allostatic 
loading'' (sensu McEwen and Wingfield, 2003). This pathological state 
will last until the animal replenishes its biotic reserves sufficient 
to restore normal function. Note that these examples involved a long-
term (days or weeks) stress response exposure to stimuli.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses have also been documented 
fairly well through controlled experiment; because this physiology 
exists in every vertebrate that has been studied, it is not surprising 
that stress responses and their costs have been documented in both 
laboratory and free-living animals (for examples see, Holberton et al., 
1996; Hood et al., 1998; Jessop et al., 2003; Krausman et al., 2004; 
Lankford et al., 2005; Reneerkens et al., 2002; Thompson and Hamer, 
2000). Although no information has been collected on the physiological 
responses of marine mammals to anthropogenic sound exposure, studies of 
other marine animals and terrestrial animals would lead us to expect 
some marine mammals to experience physiological stress responses and, 
perhaps, physiological responses that would be classified as 
``distress'' upon exposure to anthropogenic sounds. For example, Jansen 
(1998) reported on the relationship between acoustic exposures and 
physiological responses that are indicative of stress responses in 
humans (e.g., elevated respiration and increased heart rates). Jones 
(1998) reported on reductions in human performance when faced with 
acute, repetitive exposures to acoustic disturbance. Trimper et al. 
(1998) reported on the physiological stress responses of osprey to low-
level aircraft noise while Krausman et al. (2004) reported on the 
auditory and physiology stress responses of endangered Sonoran 
pronghorn to military overflights. Smith et al. (2004a, 2004b) 
identified noise-induced physiological transient stress responses in 
hearing-specialist fish (i.e., goldfish) that accompanied short- and 
long-term hearing losses. Welch and Welch (1970) reported physiological 
and behavioral stress responses that accompanied damage to the inner 
ears of fish and several mammals.
    Hearing is one of the primary senses marine mammals use to gather 
information about their environment and communicate with conspecifics. 
Although empirical information on the effects of sensory impairment 
(TTS, PTS, and acoustic masking) on marine mammals remains limited, we 
assume that reducing a marine mammal's ability to gather information 
about its environment and communicate with other members of its species 
would induce stress, based on data that terrestrial animals exhibit 
those responses under similar conditions (NRC, 2003) and because marine 
mammals use hearing as their primary sensory mechanism. Therefore, we 
assume that acoustic exposures sufficient to trigger onset PTS or TTS 
would be accompanied by physiological stress responses. Marine mammals 
might experience stress responses at received levels lower than those 
necessary to trigger onset TTS. Based on empirical studies of the time 
required to recover from stress responses (Moberg, 2000), NMFS also 
assumes that stress responses could persist beyond the time interval 
required for animals to recover from TTS and might result in 
pathological and pre-pathological states that would be as significant 
as behavioral responses to TTS. The source level of the jack-up rig is 
not loud enough to induce PTS or likely even TTS.
    Resonance effects (Gentry, 2002) and direct noise-induced bubble 
formations (Crum et al., 2005) are implausible in the case of exposure 
to an impulsive broadband source like an airgun array. If seismic 
surveys disrupt diving patterns of deep-diving species, this might 
result in bubble formation and a form of the bends, as speculated to 
occur in beaked whales exposed to sonar. However, there is no specific 
evidence of this upon exposure to airgun pulses.
    In general, very little is known about the potential for strong, 
anthropogenic underwater sounds to cause non-auditory physical effects 
in marine mammals. Such effects, if they occur at all, would presumably 
be limited to short distances and to activities that extend over a 
prolonged period. The available data do not allow identification of a 
specific exposure level above which non-auditory effects can be 
expected (Southall et al., 2007) or any meaningful quantitative 
predictions of the numbers (if any) of marine mammals that might be 
affected in those ways. There is no definitive evidence that any of 
these effects occur even for marine mammals in close proximity to large 
arrays of airguns, which are not proposed for use during this program. 
For the most part, only low-level continuous sounds would be produced 
during the drilling program as impact hammering and VSP would occur for 
only short periods of time and most of the sound produced would be from 
the ongoing operation/drilling. In addition, marine mammals that show

[[Page 35564]]

behavioral avoidance of industry activities, including belugas and some 
pinnipeds, are especially unlikely to incur non-auditory impairment or 
other physical effects.
6. Stranding and Mortality
    Marine mammals close to underwater detonations of high explosive 
can be killed or severely injured, and the auditory organs are 
especially susceptible to injury (Ketten et al., 1993; Ketten, 1995). 
Airgun pulses are less energetic and their peak amplitudes have slower 
rise times. To date, there is no evidence that serious injury, death, 
or stranding by marine mammals can occur from exposure to airgun 
pulses, even in the case of large airgun arrays. Additionally, the 
airguns used during VSP are used for short periods of time. The 
continuous sounds produced by the drill rig are also far less 
energetic.
    It should be noted that strandings known, or thought, to be related 
to sound exposure have not been recorded for marine mammal species in 
Cook Inlet. Beluga whale strandings in Cook Inlet are not uncommon; 
however, these events often coincide with extreme tidal fluctuations 
(``spring tides'') or killer whale sightings (Shelden et al., 2003). 
For example, in August 2012, a group of Cook Inlet beluga whales 
stranded in the mud flats of Turnagain Arm during low tide and were 
able to swim free with the flood tide. NMFS does not expect any marine 
mammals will incur serious injury or mortality in Cook Inlet or strand 
as a result of the proposed drilling program.

Vessel Impacts

    Vessel activity and noise associated with vessel activity will 
temporarily increase in the action area during BlueCrest's oil and gas 
production drilling program as a result of the operation of a jack-up 
drill rig and the use of tow and other support vessels. While under 
tow, the rig and the tow vessels move at slow speeds (2-4 knots). The 
support barges supplying pipe to the drill rig can typically run at 7-8 
knots but may move slower inside Cook Inlet. Based on this information, 
NMFS does not anticipate and does not propose to authorize take from 
vessel strikes.
    Odontocetes, such as beluga whales, killer whales, and harbor 
porpoises, often show tolerance to vessel activity; however, they may 
react at long distances if they are confined by ice, shallow water, or 
were previously harassed by vessels (Richardson et al., 1995a). Beluga 
whale response to vessel noise varies greatly from tolerance to extreme 
sensitivity depending on the activity of the whale and previous 
experience with vessels (Richardson et al., 1995a). Reactions to 
vessels depends on whale activities and experience, habitat, boat type, 
and boat behavior (Richardson et al., 1995a) and may include behavioral 
responses, such as altered headings or avoidance (Blane and Jaakson, 
1994; Erbe and Farmer, 2000); fast swimming; changes in vocalizations 
(Lesage et al., 1999; Scheifele et al., 2005); and changes in dive, 
surfacing, and respiration patterns.
    There are few data published on pinniped responses to vessel 
activity, and most of the information is anecdotal (Richardson et al., 
1995a). Generally, sea lions in water show tolerance to close and 
frequently approaching vessels and sometimes show interest in fishing 
vessels. They are less tolerant when hauled out on land; however, they 
rarely react unless the vessel approaches within 100-200 m (330-660 ft; 
reviewed in Richardson et al., 1995a).

Oil Spill and Discharge Impacts

    As noted above, the specified activity involves towing the rig, 
drilling of wells, and other associated support activities in lower 
Cook Inlet during the 2016 open water season. The primary stressors to 
marine mammals that are reasonably expected to occur will be acoustic 
in nature. The likelihood of a large oil spill occurring during 
BlueCrest's proposed drilling program is remote and effects from an 
event of this nature are not authorized. Offshore oil spill records in 
Cook Inlet during 1994-2011 show three spills during oil exploration 
(ADNR Division of Oil and Gas, 2011 unpub. data): Two oil spills at the 
UNOCAL Dillion Platform in June 2011 (two gallons) and December 2001 
(three gallons); and one oil spill at the UNOCAL Monopod Platform in 
January 2002 (one gallon). During this same time period, 71 spills 
occurred offshore in Cook Inlet during oil production. Most spills 
ranged from 0.0011 to 1 gallon (42 spills), and only three spills were 
larger than 200 gallons: 210 gallons in July 2001 at the Cook Inlet 
Energy Stewart facility; 250 gallons in February 1998 at the King 
Salmon platform; and 504 gallons in October 1999 at the UNOCAL Dillion 
platform. All 71 crude oil spills from the offshore platforms, both 
exploration and production, totaled less than 2,140 gallons. Based on 
historical data, most oil spills have been small. Moreover, during more 
than 60 years of oil and gas exploration and development in Cook Inlet, 
there has not been a single oil well blowout, making it difficult to 
assign a specific risk factor to the possibility of such an event in 
Cook Inlet. However, the probability of such an event is thought to be 
extremely low.
    BlueCrest will have various measures and protocols in place that 
will be implemented to prevent oil releases from the wellbore. 
BlueCrest has planned formal routine rig maintenance and surveillance 
checks, as well as normal inspection and equipment checks to be 
conducted on the jack-up rig daily. The following steps will be in 
place to prevent oil from entering the water:
     Required inspections will follow standard operating 
procedures.
     Personnel working on the rig will be directed to report 
any unusual conditions to appropriate personnel.
     Oily equipment will be regularly wiped down with oil 
absorbent pads to collect free oil. Drips and small spillage from 
equipment will be controlled through use of drip pans and oil absorbent 
drop clothes.
     Oil absorbent materials used to contain oil spills or 
seeps will be collected and disposed of in sealed plastic bags or metal 
drums and closed containers.
     The platform surfaces will be kept clean of waste 
materials and loose debris on a daily basis.
     Remedial actions will be taken when visual inspections 
indicate deterioration of equipment (tanks) and/or their control 
systems.
     Following remedial work, and as appropriate, tests will be 
conducted to determine that the systems function correctly.
    Drilling and completion fluids provide primary well control during 
drilling, work over, or completion operations. These fluids are 
designed to exert hydrostatic pressure on the wellbore that exceeds the 
pore pressures within the subsurface formations. This prevents 
undesired fluid flow into the wellbore. Surface mounted blowout 
preventer (BOP) equipment provides secondary well control. In the event 
that primary well control is lost, this surface equipment is used to 
contain the influx of formation fluid and then safely circulate it out 
of the wellbore.
    The BOP is a large, specialized valve used to seal, control, and 
monitor oil and gas wells. BOPs come in variety of styles, sizes, and 
pressure ratings. For Cook Inlet, the BOP equipment used by BlueCrest 
will consist of:
     Three BOPs pressure safety levels of: (1) 5,000 pounds per 
square inch (psi), (2) 10,000 psi, and (3) 15,000 psi;
     A minimum of three 35 cm (13\5/8\ in), 10,000 psi WP ram 
type preventers;
     One 35 cm (13\5/8\ in) annular preventer;

[[Page 35565]]

     Choke and kill lines that provide circulating paths from/
to the choke manifold;
     A two choke manifold that allows for safe circulation of 
well influxes out of the well bore; and
     A hydraulic control system with accumulator backup 
closing.
    The wellhead, associated valves, and control systems provide 
blowout prevention during well production. These systems provide 
several layers of redundancy to ensure pressure containment is 
maintained. Well control planning is performed in accordance with 
Alaska Oil and Gas Conservation Commission (AOGCC) and the Department 
of the Interior's Bureau of Safety and Environment Enforcement (BSEE) 
regulations. The operator's policies and recommended practices are, at 
a minimum, equivalent to BSEE regulations. BOP test drills are 
performed on a frequent basis to ensure the well will be shut in 
quickly and properly. BOP testing procedures will meet American 
Petroleum Institute Recommended Practice No. 53 and AOGCC 
specifications. The BOP tests will be conducted with a nonfreezing 
fluid when the ambient temperature around the BOP stack is below 0 
[deg]C (32 [deg]F). Tests will be conducted at least weekly and before 
drilling out the shoe of each casing string. The AOGCC will be 
contacted before each test is conducted, and will be onsite during BOP 
tests unless an inspection waiver is approved.
    BlueCrest developed an Oil Discharge Prevention and Contingency 
Plan (ODPCP) and has submitted it for approval to Alaska's Department 
of Environmental Conservation (ADEC). NMFS reviewed the previous ODPCP 
covering the Cosmopolitan drilling program (prepared by Buccaneer 
Alaska Operations LLC) during the ESA consultation process for 
Cosmopolitan leases and found that with implementation of the safety 
features mentioned above that the risk of an oil spill was 
discountable. As an oil spill is not a likely occurrence, it is not a 
component of BlueCrest's specified activity for which NMFS is proposing 
to authorize take.

Anticipated Effects on Marine Mammal Habitat

    The primary potential impacts to marine mammals and other marine 
species are associated with elevated sound levels produced by the 
drilling program (i.e. towing of the drill rig and the airguns). 
However, other potential impacts are also possible to the surrounding 
habitat from physical disturbance, discharges, and an oil spill (which 
we do not anticipate or authorize). This section describes the 
potential impacts to marine mammal habitat from the specified activity, 
including impacts on fish and invertebrate species typically preyed 
upon by marine mammals in the area.

Common Marine Mammal Prey in the Proposed Drilling Area

    Fish are the primary prey species for marine mammals in Cook Inlet. 
Beluga whales feed on a variety of fish, shrimp, squid, and octopus 
(Burns and Seaman, 1986). Common prey species in Knik Arm include 
salmon, eulachon and cod. Harbor seals feed on fish such as pollock, 
cod, capelin, eulachon, Pacific herring, and salmon, as well as a 
variety of benthic species, including crabs, shrimp, and cephalopods. 
Harbor seals are also opportunistic feeders with their diet varying 
with season and location. The preferred diet of the harbor seal in the 
Gulf of Alaska consists of pollock, octopus, capelin, eulachon, and 
Pacific herring (Calkins, 1989). Other prey species include cod, flat 
fishes, shrimp, salmon, and squid (Hoover, 1988). Harbor porpoises feed 
primarily on Pacific herring, cod, whiting (hake), pollock, squid, and 
octopus (Leatherwood et al., 1982). In the Cook Inlet area, harbor 
porpoise feed on squid and a variety of small schooling fish, which 
would likely include Pacific herring and eulachon (Bowen and Siniff, 
1999; NMFS, unpublished data). Killer whales feed on either fish or 
other marine mammals depending on genetic type (resident versus 
transient respectively). Killer whales in Knik Arm are typically the 
transient type (Shelden et al., 2003) and feed on beluga whales and 
other marine mammals, such as harbor seal and harbor porpoise. The 
Steller sea lion diet consists of a variety of fishes (capelin, cod, 
herring, mackerel, pollock, rockfish, salmon, sand lance, etc.), 
bivalves, squid, octopus, and gastropods.

Potential Impacts From Seafloor Disturbance on Marine Mammal Habitat

    There is a possibility of seafloor disturbance or increased 
turbidity in the vicinity of the drill sites. Seafloor disturbance 
could occur with bottom founding of the drill rig legs and anchoring 
system. These activities could lead to direct effects on bottom fauna, 
through either displacement or mortality. Increase in suspended 
sediments from seafloor disturbance also has the potential to 
indirectly affect bottom fauna and fish. The amount and duration of 
disturbed or turbid conditions will depend on sediment material.
    The potential direct habitat impact by the BlueCrest drilling 
operation is limited to the actual drill-rig footprint defined as the 
area occupied and enclosed by the drill-rig legs. The jack-up rig will 
temporarily disturb one offshore location in lower Cook Inlet, where 
the wells are proposed to be drilled. Bottom disturbance would occur in 
the area where the three legs of the rig would be set down and where 
the actual wells would be drilled. The jack-up drill rig footprint 
would occupy three steel piles at 14 m (46 ft) diameter. The well 
casing would be a 76 cm (30 in) diameter pipe extending from the 
seafloor to the rig floor. The casing would only be in place during 
drilling activities at each potential well location. The total area of 
disturbance was calculated as 0.54 acres during the land use permitting 
process. The collective 2-acre footprint of the wells represents a very 
small fraction of the 7,300 square mile Cook Inlet surface area. 
Potential damage to the Cook Inlet benthic community will be limited to 
the actual surface area of the three spudcans (1,585 square feet each 
or 4,755 square feet total) that form the ``foot'' of each leg. Given 
the high tidal energy at the well site locations, drilling footprints 
are not expected to support benthic communities equivalent to shallow 
lower energy sites found in nearshore waters where harbor seals mostly 
feed. The presence of the drill rig is not expected to result in direct 
loss of marine mammal habitat.

Potential Impacts From Sound Generation

    With regard to fish as a prey source for odontocetes and seals, 
fish are known to hear and react to sounds and to use sound to 
communicate (Tavolga et al., 1981) and possibly avoid predators (Wilson 
and Dill, 2002). Experiments have shown that fish can sense both the 
strength and direction of sound (Hawkins, 1981). Primary factors 
determining whether a fish can sense a sound signal, and potentially 
react to it, are the frequency of the signal and the strength of the 
signal in relation to the natural background noise level.
    Fish produce sounds that are associated with behaviors that include 
territoriality, mate search, courtship, and aggression. It has also 
been speculated that sound production may provide the means for long 
distance communication and communication under poor underwater 
visibility conditions (Zelick et al., 1999), although the fact that 
fish communicate at low-frequency sound levels where the masking 
effects of ambient noise are naturally highest suggests that very long

[[Page 35566]]

distance communication would rarely be possible. Fish have evolved a 
diversity of sound generating organs and acoustic signals of various 
temporal and spectral contents. Fish sounds vary in structure, 
depending on the mechanism used to produce them (Hawkins, 1993). 
Generally, fish sounds are predominantly composed of low frequencies 
(less than 3 kHz).
    Since objects in the water scatter sound, fish are able to detect 
these objects through monitoring the ambient noise. Therefore, fish are 
probably able to detect prey, predators, conspecifics, and physical 
features by listening to environmental sounds (Hawkins, 1981). There 
are two sensory systems that enable fish to monitor the vibration-based 
information of their surroundings. The two sensory systems, the inner 
ear and the lateral line, constitute the acoustico-lateralis system.
    Although the hearing sensitivities of very few fish species have 
been studied to date, it is becoming obvious that the intra- and inter-
specific variability is considerable (Coombs, 1981). Nedwell et al. 
(2004) compiled and published available fish audiogram information. A 
noninvasive electrophysiological recording method known as auditory 
brainstem response is now commonly used in the production of fish 
audiograms (Yan, 2004). Generally, most fish have their best hearing in 
the low-frequency range (i.e., less than 1 kHz). Even though some fish 
are able to detect sounds in the ultrasonic frequency range, the 
thresholds at these higher frequencies tend to be considerably higher 
than those at the lower end of the auditory frequency range.
    Literature relating to the impacts of sound on marine fish species 
can be divided into the following categories: (1) Pathological effects; 
(2) physiological effects; and (3) behavioral effects. Pathological 
effects include lethal and sub-lethal physical damage to fish; 
physiological effects include primary and secondary stress responses; 
and behavioral effects include changes in exhibited behaviors of fish. 
Behavioral changes might be a direct reaction to a detected sound or a 
result of the anthropogenic sound masking natural sounds that the fish 
normally detect and to which they respond. The three types of effects 
are often interrelated in complex ways. For example, some physiological 
and behavioral effects could potentially lead to the ultimate 
pathological effect of mortality. Hastings and Popper (2005) reviewed 
what is known about the effects of sound on fishes and identified 
studies needed to address areas of uncertainty relative to measurement 
of sound and the responses of fishes. Popper et al. (2003/2004) also 
published a paper that reviews the effects of anthropogenic sound on 
the behavior and physiology of fishes.
    Potential effects of exposure to continuous sound on marine fish 
include TTS, physical damage to the ear region, physiological stress 
responses, and behavioral responses such as startle response, alarm 
response, avoidance, and perhaps lack of response due to masking of 
acoustic cues. Most of these effects appear to be either temporary or 
intermittent and therefore probably do not significantly impact the 
fish at a population level. The studies that resulted in physical 
damage to the fish ears used noise exposure levels and durations that 
were far more extreme than would be encountered under conditions 
similar to those expected during BlueCrest's proposed exploratory 
drilling activities.
    The level of sound at which a fish will react or alter its behavior 
is usually well above the detection level. Fish have been found to 
react to sounds when the sound level increased to about 20 dB above the 
detection level of 120 dB (Ona, 1988); however, the response threshold 
can depend on the time of year and the fish's physiological condition 
(Engas et al., 1993). In general, fish react more strongly to pulses of 
sound rather than a continuous signal (Blaxter et al., 1981), such as 
the type of sound that will be produced by the drillship, and a quicker 
alarm response is elicited when the sound signal intensity rises 
rapidly compared to sound rising more slowly to the same level.
    Investigations of fish behavior in relation to vessel noise (Olsen 
et al., 1983; Ona, 1988; Ona and Godo, 1990) have shown that fish react 
when the sound from the engines and propeller exceeds a certain level. 
Avoidance reactions have been observed in fish such as cod and herring 
when vessels approached close enough that received sound levels are 110 
dB to 130 dB (Nakken, 1992; Olsen, 1979; Ona and Godo, 1990; Ona and 
Toresen, 1988). However, other researchers have found that fish such as 
polar cod, herring, and capeline are often attracted to vessels 
(apparently by the noise) and swim toward the vessel (Rostad et al., 
2006). Typical sound source levels of vessel noise in the audible range 
for fish are 150 dB to 170 dB (Richardson et al., 1995a). (Based on 
models, the 160 dB radius for the jack-up rig would extend 
approximately 33 ft [10 m]; therefore, fish would need to be in close 
proximity to the drill rig for the noise to be audible). In calm 
weather, ambient noise levels in audible parts of the spectrum lie 
between 60 dB to 100 dB.
    BlueCrest also proposes to conduct VSP surveys with an airgun array 
for a short period of time during the drilling season (only a few hours 
over 1-2 days over the course of the entire proposed drilling program). 
Airguns produce impulsive sounds as opposed to continuous sounds at the 
source. Short, sharp sounds can cause overt or subtle changes in fish 
behavior. Chapman and Hawkins (1969) tested the reactions of whiting 
(hake) in the field to an airgun. When the airgun was fired, the fish 
dove from 82 to 180 ft (25 to 55 m) depth and formed a compact layer. 
The whiting dove when received sound levels were higher than 178 dB re 
1 [micro]Pa (Pearson et al., 1992).
    Pearson et al. (1992) conducted a controlled experiment to 
determine effects of strong noise pulses on several species of rockfish 
off the California coast. They used an airgun with a source level of 
223 dB re 1 [micro]Pa. They noted:
     Startle responses at received levels of 200-205 dB re 1 
[micro]Pa and above for two sensitive species, but not for two other 
species exposed to levels up to 207 dB;
     Alarm responses at 177-180 dB for the two sensitive 
species, and at 186 to 199 dB for other species;
     An overall threshold for the above behavioral response at 
about 180 dB;
     An extrapolated threshold of about 161 dB for subtle 
changes in the behavior of rockfish; and
     A return to pre-exposure behaviors within the 20-60 minute 
exposure period.
    In summary, fish often react to sounds, especially strong and/or 
intermittent sounds of low frequency. Sound pulses at received levels 
of 160 dB re 1 [micro]Pa may cause subtle changes in behavior. Pulses 
at levels of 180 dB may cause noticeable changes in behavior (Chapman 
and Hawkins, 1969; Pearson et al., 1992; Skalski et al., 1992). It also 
appears that fish often habituate to repeated strong sounds rather 
rapidly, on time scales of minutes to an hour. However, the habituation 
does not endure, and resumption of the strong sound source may again 
elicit disturbance responses from the same fish. Underwater sound 
levels from the drill rig and other vessels produce sounds lower than 
the response threshold reported by Pearson et al. (1992), and are not 
likely to result in major effects to fish near the proposed drill site.
    Based on a sound level of approximately 140 dB, there may be some 
avoidance by fish of the area near

[[Page 35567]]

the jack-up while drilling, around the rig under tow, and around other 
support and supply vessels when underway. Any reactions by fish to 
these sounds will last only minutes (Mitson and Knudsen, 2003; Ona et 
al., 2007) longer than the vessel is operating at that location or the 
drill rig is drilling. Any potential reactions by fish would be limited 
to a relatively small area within about 33 ft (10 m) of the drill rig 
during drilling. Avoidance by some fish or fish species could occur 
within portions of this area.
    The lease areas do not support major populations of cod, Pollock, 
and sole, although all four salmon species and smelt may migrate 
through the area to spawning rivers in upper Cook Inlet (Shields and 
Dupuis, 2012). Residency time for the migrating finfish in the vicinity 
of an operating platform would be short-term, limiting fish exposure to 
noise associated with the proposed drilling program.
    Some of the fish species found in Cook Inlet are prey sources for 
odontocetes and pinnipeds. A reaction by fish to sounds produced by 
BlueCrest's proposed operations would only be relevant to marine 
mammals if it caused concentrations of fish to vacate the area. 
Pressure changes of sufficient magnitude to cause that type of reaction 
would probably occur only very close to the sound source, if any would 
occur at all due to the low energy sounds produced by the majority of 
equipment proposed for use. Impacts on fish behavior are predicted to 
be inconsequential. Thus, feeding odontocetes and pinnipeds would not 
be adversely affected by this minimal loss or scattering, if any, which 
is not expected to result in reduced prey abundance. The proposed 
drilling area is not a common feeding area for baleen whales.

Potential Impacts From Drilling Discharges

    The drill rig Spartan151 will operate under the Alaska Pollutant 
Discharge Elimination System (APDES) general permit AKG-31-5021 for 
wastewater discharges (ADEC, 2012). This permit authorizes discharges 
from oil and gas extraction facilities engaged in exploration under the 
Offshore and Coastal Subcategories of the Oil and Gas Extraction Point 
Source Category (40 CFR part 435). Twelve effluents are authorized for 
discharge into Cook Inlet once ADEC discharge limits have been met. The 
authorized discharges include: Drilling fluids and drill cuttings, deck 
drainage, sanitary waste, domestic waste, blowout preventer fluid, 
boiler blow down, fire control system test water, uncontaminated 
ballast water, bilge water, excess cement slurry, mud cuttings cement 
at sea floor, and completion fluids. Areas prohibited from discharge in 
the Cook Inlet are 10-meter (33-foot) isobaths, 5-meter (16-foot) 
isobaths, and other geographic area restrictions (AKG-31-5021.I.C.). 
The Spartan151 is also authorized under EPA's Vessel General Permit for 
deck wash down and runoff, gray water, and gray water mixed with sewage 
discharges. The effluent limits and related requirements for these 
discharges in the Vessel General Permit are to minimize or eliminate to 
the extent achievable using control measures (best management 
practices) (EPA, 2011).
    Drilling wastes include drilling fluids, known as mud, rock 
cuttings, and formation waters. Drilling wastes (non-hydrocarbon) will 
be discharged to the Cook Inlet under the approved APDES general 
permit. Drilling wastes (hydrocarbon) will be delivered to an onshore 
permitted location for disposal. During drilling, the onsite tool 
pusher/driller and qualified mud engineers will direct and maintain 
desired mud properties, and maintain the quantities of basic mud 
materials on site as dictated by good oilfield practice. BlueCrest will 
follow best management practices to ensure that a sufficient inventory 
of barite and lost circulation materials are maintained on the drilling 
vessel to minimize the possibility of a well upset and the likelihood 
of a release of pollutants to Cook Inlet waters. These materials can be 
re-supplied, if required, using the supply vessel. Because adverse 
weather could prevent immediate re-supply, sufficient materials will be 
available on board to completely rebuild the total circulating volume. 
BlueCrest will conduct an Environmental Monitoring Study of relevant 
hydrographic, sediment hydrocarbon, and heavy metal data from surveys 
conducted before and during drilling mud disposal and up to a least one 
year after drilling operations cease in accordance with the APDES 
general permit for discharges of drilling muds and cuttings.
    Non-drilling wastewater includes deck drainage, sanitary waste, 
domestic waste, blowout preventer fluid, boiler blow down, fire control 
test water, bilge water, non-contact cooling water, and uncontaminated 
ballast water. Non-drilling wastewater will be discharged into Cook 
Inlet under the approved APDES general permit or delivered to an 
onshore permitted location for disposal. Mud cuttings will be 
constantly tested. No hydrocarboned muds will be permitted to be 
discharged into Cook Inlet. They will be hauled offsite. Solid waste 
(e.g., packaging, domestic trash) will be classified, segregated, and 
labeled as general, universal, and Resource Conservation and Recovery 
Act exempt or non-exempt waste. It will be stored in containers at 
designated accumulation areas. Then, it will be packaged and palletized 
for transport to an approved on-shore disposal facility. No hazardous 
wastes should be generated as a result of this project. However, if any 
hazardous wastes were generated, it would be temporarily stored in an 
onboard satellite accumulation area and then transported offsite for 
disposal at an approved facility.
    With oil and gas platforms presently operating in Cook Inlet, there 
is concern for continuous exposure to potentially toxic heavy metals 
and metalloids (i.e., mercury, lead, cadmium, copper, zinc, and 
arsenic) that are associated with oil and gas development and 
production. These elements occur naturally in the earth's crust and the 
oceans but many also have anthropogenic origins from local sources of 
pollution or from contamination from atmospheric distribution.
    Discharging drill cuttings or other liquid waste streams generated 
by the drilling vessel could potentially affect marine mammal habitat. 
Toxins could persist in the water column, which could have an impact on 
marine mammal prey species. However, despite a considerable amount of 
investment in research on exposures of marine mammals to 
organochlorines or other toxins, there have been no marine mammal 
deaths in the wild that can be conclusively linked to the direct 
exposure to such substances (O'Shea, 1999).
    Drilling muds and cuttings discharged to the seafloor can lead to 
localized increased turbidity and increase in background concentrations 
of barium and occasionally other metals in sediments and may affect 
lower trophic organisms. Drilling muds are composed primarily of 
bentonite (clay), and the toxicity is therefore low. Heavy metals in 
the mud may be absorbed by benthic organisms, but studies have shown 
that heavy metals do not bio-magnify in marine food webs (Neff et al., 
1989). Effects on benthic communities are nearly always restricted to a 
zone within about 328 to 492 ft (100 to 150 m) of the discharge, where 
cuttings accumulations are greatest. Discharges and drill cuttings 
could impact fish by displacing them from the affected area.
    Levels of heavy metals and other elements (cadmium, mercury, 
selenium, vanadium, and silver) were generally

[[Page 35568]]

lower in the livers of Cook Inlet beluga whales than those of other 
beluga whale stocks, while copper was higher (Becker et al., 2001). 
Hepatic methyl mercury levels were similar to those reported for other 
beluga whales (Geraci and St. Aubin, 1990). The relatively high hepatic 
concentration of silver found in the eastern Chukchi Sea and Beaufort 
Sea stocks of belugas was also found in the Cook Inlet animals, 
suggesting a species-specific phenomenon. However, because of the 
limited discharges, no water quality impacts are anticipated that would 
negatively affect habitat for Cook Inlet marine mammals.

Potential Impacts From Drill Rig Presence

    The horizontal dimensions of the Spartan151 jack-up rig are 147 ft 
by 30 ft. The dimensions of the drill rig (less than one football field 
on either side) are not significant enough to cause a large-scale 
diversion from the animals' normal swim and migratory paths. Any 
deflection of marine mammal species due to the physical presence of the 
drill rig would be very minor. The drill rig's physical footprint is 
small relative to the size of the geographic region it will occupy and 
will likely not cause marine mammals to deflect greatly from their 
typical migratory route. Also, even if animals may deflect because of 
the presence of the drill rig, Cook Inlet is much larger in size than 
the length of the drill rig (many dozens of miles vs. less than one 
football field), and animals would have other means of passage around 
the drill rig. In sum, the physical presence of the drill rig is not 
likely to cause a significant deflection to migrating marine mammals.

Potential Impacts From an Oil Spill

    As noted above, an oil spill is not a likely occurrence, it is not 
a component of BlueCrest's specified activity for which NMFS is 
proposing to authorize take. Also, as noted above, NMFS previously 
considered potential effects of an oil spill in the unlikely event that 
it happened and determined the effects discountable, and there has been 
no new information that would change this determination at this time.
    Based on the consideration of potential types of impacts to marine 
mammal habitat, and taking into account the very low potential for a 
large or very large oil spill, overall, the proposed specified activity 
is not expected to cause significant impacts on habitats used by the 
marine mammal species in the proposed project area, including the food 
sources that they utilize.

Proposed Mitigation

    In order to issue an incidental take authorization (ITA) under 
section 101(a)(5)(D) of the MMPA, NMFS must set forth the permissible 
methods of taking pursuant to such activity, and other means of 
effecting the least practicable impact on such species or stock and its 
habitat, paying particular attention to rookeries, mating grounds, and 
areas of similar significance, and on the availability of such species 
or stock for taking for certain subsistence uses (where relevant). 
Later in this document in the ``Proposed Incidental Harassment 
Authorization'' section, NMFS lays out the proposed conditions for 
review, as they would appear in the final IHA (if issued).
    The drill rig does not emit sound levels that would result in Level 
A harassment (injury), which NMFS typically requires applicants to 
avoid through mitigation (such as shutdowns). For continuous sounds, 
such as those produced by drilling operations and rig tow, NMFS uses a 
received level of 120-dB (rms) for the onset of Level B harassment. For 
impulse sounds, such as those produced by the airgun array during the 
VSP surveys or the impact hammer during drive pipe driving, NMFS uses a 
received level of 160-dB (rms) for the onset of Level B harassment. The 
current Level A (injury) harassment threshold is 180 dB (rms) for 
cetaceans and 190 dB (rms) for pinnipeds. Table 2 outlines the various 
applicable radii that inform mitigation.

                      Table 2--Applicable Mitigation and Shutdown Radii for BlueCrest's Proposed Lower Cook Inlet Drilling Program
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            190 dB radius                 180 dB radius                160 dB radius                120 dB radius
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact hammer during drive pipe     60 m (200 ft)...............  250 m (820 ft)..............  1.6 km (1 mi)..............  NA.
 hammering.
Airguns during VSP................  120 m (394 ft)..............  240 m (787 ft)..............  2.5 km (1.55 mi)...........  NA.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not applicable.

Mitigation Measures Proposed by BlueCrest

    For the proposed mitigation measures, BlueCrest listed the 
following protocols to be implemented during its drilling program in 
Cook Inlet.
1. Drive Pipe Hammering Measures
    Two protected species observers (PSOs), working alternate shifts, 
will be stationed aboard the drill rig during all pipe driving 
activities at the well. Standard marine mammal observing field 
equipment will be used, including reticule binoculars (10x42), big-eye 
binoculars (30x), inclinometers, and range finders. The PSOs will be 
stationed as close to the well head as safely possible, and will 
observe from the drill rig during this 2-3 day portion of the proposed 
program out to the 160 dB (rms) radius of 1.6 km (1 mi). Drive pipe 
hammering will be limited to daylight hours, and when sea conditions 
are light; therefore, marine mammal observation conditions will be 
generally good. If cetaceans enter within the 180 dB (rms) radius of 
250 m (820 ft), or if pinnipeds enter within the 190 dB (rms) radius of 
60 m (200 ft), then use of the impact hammer will cease. If any beluga 
whales, or any cetacean for which take has not been authorized, are 
detected entering the 160 dB disturbance zone activities will cease 
until the animal has been visually confirmed to clear the zone or is 
unseen for at least 30 minutes. Following a shutdown of impact 
hammering activities, the applicable zones must be clear of marine 
mammals for at least 30 minutes prior to restarting activities.
    BlueCrest proposes to follow a ramp-up procedure during impact 
hammering activities. PSOs will visually monitor out to the 160 dB 
radius for at least 30 minutes prior to the initiation of activities. 
If no marine mammals are detected during that time, then BlueCrest can 
initiate impact hammering using a ``soft start'' technique. Hammering 
will begin with an initial set of three strikes at 40 percent energy 
followed by a 1 min waiting period, then two subsequent three-strike 
sets. This ``soft-start'' procedure will be implemented anytime impact 
hammering has ceased for 30 minutes or more. Impact hammer ``soft-
start'' will not be required if the hammering downtime is for less than 
30 minutes and visual surveys are continued throughout the silent 
period

[[Page 35569]]

and no marine mammals are observed in the applicable zones during that 
time. Monitoring will occur during all hammering sessions.
2. VSP Airgun Measures
    As with pipe driving, two PSOs will observe from the drill rig 
during this 1-2 day portion of the proposed program out to the 160 dB 
radius of 2.5 km (1.55 mi). Standard marine mammal observing field 
equipment will be used, including reticule binoculars (10x42), big-eye 
binoculars (30x), inclinometers, and range finders. Monitoring during 
zero-offset VSP will be conducted by two PSOs operating from the drill 
rig. During walk-away VSP operations, an additional two PSOs will 
monitor from the seismic source vessel. VSP activities will be limited 
to daylight hours, and when sea conditions are light; therefore, marine 
mammal observation conditions will be generally good. If cetaceans 
enter within the 180 dB (rms) radius of 240 m (787 ft) or if pinnipeds 
enter within the 190 dB (rms) radius of 120 m (394 ft), then use of the 
airguns will cease. If any beluga whales, or any cetacean for which 
take has not been authorized, are detected entering the 160 dB 
disturbance zone, activities will cease until the animal has been 
visually confirmed to clear the zone or is unseen for at least 30 
minutes. Following a shutdown of airgun operations, the applicable 
zones must be clear of marine mammals for at least 30 minutes prior to 
restarting activities.
    BlueCrest proposes to follow a ramp-up procedure during airgun 
operations. PSOs will visually monitor out to the 160 dB radius for at 
least 30 minutes prior to the initiation of activities. If no marine 
mammals are detected during that time, then BlueCrest can initiate 
airgun operations using a ``ramp-up'' technique. Airgun operations will 
begin with the firing of a single airgun, which will be the smallest 
gun in the array in terms of energy output (dB) and volume (in\3\). 
Operators will then continue ramp-up by gradually activating additional 
airguns over a period of at least 30 minutes (but not longer than 40 
minutes) until the desired operating level of the airgun array is 
obtained. This ramp-up procedure will be implemented anytime airguns 
have not been fired for 30 minutes or more. Airgun ramp-up will not be 
required if the airguns have been off for less than 30 minutes and 
visual surveys are continued throughout the silent period and no marine 
mammals are observed in the applicable zones during that time. 
Monitoring will occur during all airgun usage.
3. Oil Spill Plan
    BlueCrest developed an Oil Discharge Prevention and Contingency 
Plan (ODPCP) and has submitted it for approval to Alaska's Department 
of Environmental Conservation (ADEC). NMFS reviewed the previous ODPCP 
covering the Cosmopolitan drilling program (prepared by Buccaneer 
Alaska Operations LLC) during the ESA consultation process for 
Cosmopolitan leases and found that with implementation of the safety 
features mentioned above that the risk of an oil spill was 
discountable. The new ODPCP for operations under BlueCrest was approved 
on March 30, 2016.
4. Pollution Discharge Plan
    When the drill rig is towed or otherwise floating it is classified 
as a vessel (like a barge). During those periods, it is covered under a 
form of National Pollutant Discharge Elimination System permit known as 
a Vessel General Permit. This permit remains federal and is a ``no 
discharge permit,'' which allows for the discharge of storm water and 
closed system fire suppression water but no other effluents.
    When the legs are down, the drill rig becomes a facility. During 
those periods, it is covered under an approved APDES. Under the APDES, 
certain discharges are permitted. However, BlueCrest is not permitted 
to discharge gray water, black water, or hydrocarboned muds; they are 
all hauled off and not discharged.

Mitigation Measures Proposed by NMFS

    NMFS proposes that: during rig towing operations, speed will be 
reduced to 8 knots or less, as safety allows, at the approach of any 
whales or Steller sea lions within 2,000 ft (610 m) of the towing 
operations; and when BlueCrest utilizes helicopters for support 
operations that the helicopters must maintain an altitude of at least 
1,000 ft (305 m), except during takeoffs, landings, or emergency 
situations.

Mitigation Conclusions

    NMFS has carefully evaluated BlueCrest's proposed mitigation 
measures and considered a range of other measures in the context of 
ensuring that NMFS prescribes the means of affecting the least 
practicable impact on the affected marine mammal species and stocks and 
their habitat. Our evaluation of potential measures included 
consideration of the following factors in relation to one another:
     The manner in which, and the degree to which, the 
successful implementation of the measures are expected to minimize 
adverse impacts to marine mammals;
     The proven or likely efficacy of the measures to minimize 
adverse impacts as planned; and
     The practicability of the measures for applicant 
implementation.
    Any mitigation measure(s) prescribed by NMFS should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below:
    1. Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    2. A reduction in the numbers of marine mammals (total number or 
number at biologically important time or location) exposed to received 
levels of seismic airguns, impact hammers, drill rig deep well pumps, 
or other activities expected to result in the take of marine mammals 
(this goal may contribute to 1, above, or to reducing harassment takes 
only).
    3. A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to received levels of seismic airguns impact hammers, drill rig deep 
well pumps, or other activities expected to result in the take of 
marine mammals (this goal may contribute to 1, above, or to reducing 
harassment takes only).
    4. A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to received 
levels of seismic airguns impact hammers, drill rig deep well pumps, or 
other activities expected to result in the take of marine mammals (this 
goal may contribute to 1, above, or to reducing the severity of 
harassment takes only).
    5. Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/disturbance 
of habitat during a biologically important time.
    6. For monitoring directly related to mitigation--an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures proposed by NMFS, NMFS has preliminarily 
determined that implementation of these mitigation measures provide the 
means of effecting

[[Page 35570]]

the least practicable impact on marine mammals species or stocks and 
their habitat, paying particular attention to rookeries, mating 
grounds, and areas of similar significance.

Proposed Monitoring and Reporting

    In order to issue an ITA 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 ITAs 
must include the suggested means of accomplishing the necessary 
monitoring and reporting that will result in increased knowledge of the 
species and of the level of taking or impacts on populations of marine 
mammals that are expected to be present in the proposed action area. 
BlueCrest submitted information regarding marine mammal monitoring to 
be conducted during the proposed drilling program as part of the IHA 
application. That information can be found in the Appendix of their 
application. The monitoring measures may be modified or supplemented 
based on comments or new information received from the public during 
the public comment period.
    Monitoring measures proposed by the applicant or prescribed by NMFS 
should accomplish one or more of the following top-level goals:
    1. An increase in our understanding of the likely occurrence of 
marine mammal species in the vicinity of the action, i.e., presence, 
abundance, distribution, and/or density of species.
    2. An increase in our understanding of the nature, scope, or 
context of the likely exposure of marine mammal species to any of the 
potential stressor(s) associated with the action (e.g. sound or visual 
stimuli), through better understanding of one or more of the following: 
the action itself and its environment (e.g. sound source 
characterization, propagation, and ambient noise levels); the affected 
species (e.g. life history or dive pattern); the likely co-occurrence 
of marine mammal species with the action (in whole or part) associated 
with specific adverse effects; and/or the likely biological or 
behavioral context of exposure to the stressor for the marine mammal 
(e.g. age class of exposed animals or known pupping, calving or feeding 
areas).
    3. An increase in our understanding of how individual marine 
mammals respond (behaviorally or physiologically) to the specific 
stressors associated with the action (in specific contexts, where 
possible, e.g., at what distance or received level).
    4. An increase in our understanding of how anticipated individual 
responses, to individual stressors or anticipated combinations of 
stressors, may impact either: the long-term fitness and survival of an 
individual; or the population, species, or stock (e.g. through effects 
on annual rates of recruitment or survival).
    5. An increase in our understanding of how the activity affects 
marine mammal habitat, such as through effects on prey sources or 
acoustic habitat (e.g., through characterization of longer-term 
contributions of multiple sound sources to rising ambient noise levels 
and assessment of the potential chronic effects on marine mammals).
    6. An increase in understanding of the impacts of the activity on 
marine mammals in combination with the impacts of other anthropogenic 
activities or natural factors occurring in the region.
    7. An increase in our understanding of the effectiveness of 
mitigation and monitoring measures.
    8. An increase in the probability of detecting marine mammals 
(through improved technology or methodology), both specifically within 
the safety zone (thus allowing for more effective implementation of the 
mitigation) and in general, to better achieve the above goals.

Proposed Monitoring Measures

1. Visual Monitoring
    PSOs will be required to monitor the area for marine mammals aboard 
the drill rig during drilling operations, drive pipe hammering, and VSP 
operations. Standard marine mammal observing field equipment will be 
used, including reticule binoculars, Big-eye binoculars, inclinometers, 
and range-finders. Drive pipe hammering and VSP operations will not 
occur at night, so PSOs will not be on watch during nighttime. At least 
one PSO will be on duty at all times when operations are occurring. 
Shifts shall not last more than 4 hours, and PSOs will not observe for 
more than 12 hours in a 24-hour period.
2. Sound Source Verification Monitoring
    Sound source verification (SSV) measurements have already been 
conducted for the Spartan151 and all other sound generating activities 
planned at the Cosmopolitan well site by MAI (2011). No SSV 
measurements are planned at this time for the 2016 program.

Reporting Measures

1. 90-Day Technical Report
    Daily field reports will be prepared that include daily activities, 
marine mammal monitoring efforts, and a record of the marine mammals 
and their behaviors and reactions observed that day. These daily 
reports will be used to help generate the 90-day technical report. A 
report will be due to NMFS no later than 90 days after the expiration 
of the IHA (if issued). The Technical Report will include the 
following:
     Summaries of monitoring effort (e.g., total hours, total 
distances, and marine mammal distribution through the study period, 
accounting for sea state and other factors affecting visibility and 
detectability of marine mammals).
     Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare).
     Species composition, occurrence, and distribution of 
marine mammal sightings, including date, water depth, numbers, age/
size/gender categories (if determinable), group sizes, and ice cover.
     Analyses of the effects of operations.
     Sighting rates of marine mammals (and other variables that 
could affect detectability), such as: (i) Initial sighting distances 
versus operational activity state; (ii) closest point of approach 
versus operational activity state; (iii) observed behaviors and types 
of movements versus operational activity state; (iv) numbers of 
sightings/individuals seen versus operational activity state; (v) 
distribution around the drill rig versus operational activity state; 
and (vi) estimates of take by Level B harassment based on presence in 
the Level B harassment zones.
2. Notification of Injured or Dead Marine Mammals
    In the unanticipated event that BlueCrest's specified activity 
clearly causes the take of a marine mammal in a manner prohibited by 
the IHA (if issued), such as an injury (Level A harassment), serious 
injury or mortality (e.g., ship-strike, gear interaction, and/or 
entanglement), BlueCrest would immediately cease the specified 
activities and immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
the Alaska Region Protected Resources Division, NMFS, and the Alaska 
Regional Stranding Coordinators. The report would include the following 
information:

[[Page 35571]]

     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with BlueCrest to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. BlueCrest would not be able 
to resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that BlueCrest discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition as described in the next paragraph), 
BlueCrest would immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
the Alaska Region Protected Resources Division, NMFS, and the NMFS 
Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators. The report would include the same information 
identified in the paragraph above. If the observed marine mammal is 
dead, activities would be able to continue while NMFS reviews the 
circumstances of the incident. If the observed marine mammal is 
injured, measures described below must be implemented. NMFS would work 
with BlueCrest to determine whether modifications in the activities are 
appropriate.
    In the event that BlueCrest discovers an injured or dead marine 
mammal, and the lead PSO determines that the injury or death is not 
associated with or related to the activities authorized in the IHA 
(e.g., carcass with moderate to advanced decomposition, or scavenger 
damage), BlueCrest would report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
the Alaska Region Protected Resources Division, NMFS, and the NMFS 
Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators, within 24 hours of the discovery. BlueCrest 
would provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network. If the observed marine mammal is dead, 
activities may continue while NMFS reviews the circumstances of the 
incident. If the observed marine mammal is injured, measures described 
below must be implemented. In this case, NMFS will notify BlueCrest 
when activities may resume.
3. Injured Marine Mammals
    The following describe the specific actions BlueCrest must take if 
a live marine mammal stranding is reported in Cook Inlet coincident to, 
or within 72 hours of seismic activities involving the use of airguns. 
A live stranding event is defined as a marine mammal: (i) On a beach or 
shore of the United States and unable to return to the water; (ii) on a 
beach or shore of the United States and, although able to return to the 
water, is in apparent need of medical attention; or (iii) in the waters 
under the jurisdiction of the United States (including navigable 
waters) but is unable to return to its natural habitat under its own 
power or without assistance.
    The shutdown procedures described here are not related to the 
investigation of the cause of the stranding and their implementation is 
in no way intended to imply that BlueCrest's airgun operation is the 
cause of the stranding. Rather, shutdown procedures are intended to 
protect marine mammals exhibiting indicators of distress by minimizing 
their exposure to possible additional stressors, regardless of the 
factors that initially contributed to the stranding.
    Should BlueCrest become aware of a live stranding event (from NMFS 
or another source), BlueCrest must immediately implement a shutdown of 
the airgun array. A shutdown must be implemented whenever the animal is 
within 5 km of the airgun array. Shutdown procedures will remain in 
effect until NMFS determines that, and advises BlueCrest that, all live 
animals involved in the stranding have left the area (either of their 
own volition or following herding by responders).
    Within 48 hours of the notification of the live stranding event, 
BlueCrest must inform NMFS where and when they were operating airguns 
and at what discharge volumes. BlueCrest must appoint a contact who can 
be reached 24/7 for notification of live stranding events. Immediately 
upon notification of the live stranding event, this person must order 
the immediate shutdown of the airguns. These conditions are in addition 
to those noted above.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment]. Only take by Level B behavioral 
harassment of some species is anticipated as a result of the proposed 
drilling program. Anticipated impacts to marine mammals are associated 
with noise propagation from the sound sources (e.g., drill rig and tow, 
airguns, and impact hammer) used in the drilling program. Additional 
disturbance to marine mammals may result from visual disturbance of the 
drill rig or support vessels. No take is expected to result from vessel 
strikes because of the slow speed of the vessels (2-4 knots while rig 
is under tow; 7-8 knots for supply barges).
    BlueCrest requests authorization to take nine marine mammal species 
by Level B harassment. These nine marine mammal species are: beluga 
whale; humpback whale; gray whale; minke whale; killer whale; harbor 
porpoise; Dall's porpoise; Steller sea lion; and harbor seal. In April 
2013, NMFS Section 7 ESA biologists concurred that Buccaneer's proposed 
Cosmopolitan exploratory drilling program was not likely to adversely 
affect Cook Inlet beluga whales or beluga whale critical habitat. Since 
the sale of the Cosmopolitan leases from Buccaneer to BlueCrest and the 
slight change in the program (e.g., drilling of up to three wells 
instead of two), Mitigation measures requiring shutdowns of activities 
before belugas enter the Level B harassment zones will be required in 
any issued IHA. Therefore, the potential for take of belugas would be 
eliminated; however, a small number of takes are included to cover any 
unexpected or accidental take.
    As noted previously in this document, for continuous sounds, for 
impulse sounds such as those produced by the airgun array during the 
VSP surveys or

[[Page 35572]]

the impact hammer during drive pipe hammering, NMFS uses a received 
level of 160-dB (rms) to indicate the onset of Level B harassment. The 
current Level A (injury) harassment threshold is 180 dB (rms) for 
cetaceans and 190 dB (rms) for pinnipeds. Table 3 outlines the current 
acoustic criteria.

            Table 3--Acoustic Exposure Criteria Used by NMFS
------------------------------------------------------------------------
          Criterion           Criterion definition        Threshold
------------------------------------------------------------------------
Level A Harassment (Injury).  Permanent Threshold   180 dB re 1 microPa-
                               Shift (PTS) (Any      m (cetaceans)/190
                               level above that      dB re 1 micro-m
                               which is known to     (pinnipeds) root
                               cause TTS).           mean square (rms).
Level B Harassment..........  Behavioral            160 dB re 1 microPa-
                               Disruption (for       m (rms).
                               impulse noises).
------------------------------------------------------------------------

    Section 6 of BlueCrest's application contains a description of the 
methodology used by BlueCrest to estimate takes by harassment, 
including calculations for the 120 dB (rms) and 160 dB (rms) isopleths 
and marine mammal densities in the areas of operation (see ADDRESSES), 
which is also provided in the following sections. NMFS verified 
BlueCrest's methods, and used the density and sound isopleth 
measurements in estimating take. However, NMFS also include a duration 
factor in the estimates presented below, which is not included in 
BlueCrest's application.
    The proposed take estimates presented in this section were 
calculated by multiplying the best available density estimate for the 
species (from NMFS aerial surveys 2005-2014) by the area of 
ensonification for each type of activity by the total number of days 
that each activity would occur. While the density and sound isopleth 
data helped to inform the decision for the proposed estimated take 
levels for harbor porpoises and harbor seals, NMFS also considered the 
information regarding marine mammal sightings during BlueCrest's 2013 
Cosmopolitan #A-1 drilling program. Additional detail is provided next.

Ensonified Areas

Drive Pipe Hammering
    The Delmar D62-22 diesel impact hammer proposed to be used by 
BlueCrest to drive the 30-inch drive pipe was previously acoustically 
measured by Blackwell (2005) in upper Cook Inlet. She found that sound 
exceeding 190 dB Level A noise limits for pinnipeds extend to about 200 
ft (60 m), and 180 dB Level A impacts to cetaceans to about 820 ft (250 
m). Level B disturbance levels of 160 dB extended to just less than 1 
mi (1.6 km). The associated ZOI (area ensonified by noise greater than 
160 dB) is 8.3 km\2\ (3.1 mi\2\).
VSP Airguns
    Illingworth and Rodkin (2014) measured noise levels during VSP 
operations associated with post-drilling operations at the Cosmopolitan 
#A-1 site in lower Cook Inlet during July 2013. The results indicated 
that the 720 cubic inch airgun array used during the operation produced 
noise levels exceeding 160 dB re 1 [mu]Pa out to a distance of 
approximately 8,100 ft (2,470 m). Based on these results, the 
associated ZOI would be 19.17 km\2\ (7.4 mi\2\). See Table 4.

           Table 4--Zones of Influence for Proposed Activities
------------------------------------------------------------------------
                                           Drive pipe
                                           hammering       VSP Airguns
------------------------------------------------------------------------
ZOI (km\2\)...........................             8.3            19.17
------------------------------------------------------------------------

Marine Mammal Densities

    Density estimates were derived for Cook Inlet marine mammals other 
than belugas as described above. An average density was derived for 
each species based on NMFS aerial survey data from 2005-2014.
    For belugas, the ensonified area associated with each activity was 
overlaid on a map of the density cells derived in Goetz et al. (2012), 
the cells falling within each ensonified area were quantified, and 
average cell density calculated. Figure 6-1 in BlueCrest's application 
shows the associated ensonified areas and beluga density contours 
relative to the rig tow beginning from Port Graham, while Figure 6-2 
shows the same but assumes the rig tow to the well site will begin in 
upper Cook Inlet. The quantified results are found in Table 5 below, 
and show that throughout the proposed activity areas the beluga 
densities are very low.

  Table 5--Mean Raw Densities of Beluga Whales With Activity Action Areas Based on the Goetz et al. (2012) Cook
                                    Inlet Beluga Whale Distribution Modeling
----------------------------------------------------------------------------------------------------------------
               Activity                    Number of cells            Mean density            Density range
----------------------------------------------------------------------------------------------------------------
Pipe Driving.........................                        8                 0.000344        0.000200-0.000562
VSP..................................                       19                 0.000346        0.000136-0.000755
----------------------------------------------------------------------------------------------------------------

    This data was then multiplied by the area ensonified in one day, 
then multiplied by the number of expected days of each type of 
operation.

Proposed Take Estimates

    As noted previously in this document, the potential number of 
animals that might be exposed to receive continuous SPLs of >=120 dB re 
1 [mu]Pa (rms) and pulsed SPLs of >=160 dB re 1 [mu]Pa (rms) was 
calculated by multiplying:
     The expected species density;
     the anticipated area to be ensonified (zone of influence 
[ZOI]); and
     the estimated total duration of each of the activities 
expressed in days (24 hrs).
    To derive at an estimated total duration for each of the activities 
the following assumptions were made:
     The maximum total duration of impact hammering during 
drive pipe driving would be 3 days (however, the hammer would not be 
used continuously over that time period).
     The total duration of the VSP data acquisition runs is 
estimated to be up to 2 days (however, the airguns would not be used 
continuously over that time period).
    Using all of these assumptions, Table 6 outlines the total number 
of Level B harassment exposures for each species from each of the four 
activities using the

[[Page 35573]]

calculation and assumptions described here.

  Table 6--Potential Number of Exposures to Level B Harassment Thresholds During BlueCrest's Proposed Drilling
                                    Program During the 2016 Open Water Season
----------------------------------------------------------------------------------------------------------------
                             Species                               Pipe driving         VSP            Total
----------------------------------------------------------------------------------------------------------------
Beluga whale....................................................             0.1             0.1             0.2
Gray whale......................................................              <1              <1              <1
Harbor seal.....................................................            20.7            31.9            52.6
Harbor porpoise.................................................             0.3             0.5             0.8
Killer whale....................................................             0.1             0.1             0.2
Steller sea lion................................................             0.7             1.0             1.7
Minke whale.....................................................              <1              <1              <1
Humpback whale..................................................             0.1             0.1             0.2
Dall's porpoise.................................................              <1              <1              <1
----------------------------------------------------------------------------------------------------------------

    In the IHA application, BlueCrest notes that these estimates may be 
low regarding harbor porpoise and killer whales, and high regarding 
harbor seals, based on 2013 marine mammal monitoring data (Owl Ridge, 
2014). During the 2013 monitoring, 152 harbor porpoise were observed 
within about 2 km (1.2 mi). If we assume that the 1,999 hours of 
observation effort in 2013 equates to about 83 days (24-hr periods), 
then we can assume that about 2 harbor porpoise were recorded for every 
24 hr of monitoring effort in 2013. Consequently, it is reasonable to 
assume that the 15 total days of activity associated with pipe driving 
and VSP combined could expose approximately 30 harbor porpoise. 
Following this same logic, the 17 killer whales, 77 harbor seals, and 7 
Steller sea lions that were observed within about 2 km (1.2 mi) in 
2013, would equate to an expectation of about 3 killer whale, 14 harbor 
seals, and 1 Steller sea lion occurring within 2 km (1.2 mi) of the rig 
during the planned 15 total days of pipe driving and VSP activity. The 
larger of the two estimates was used for each species.
    For the less common marine mammals such as gray, minke, and killer 
whales and Dall's porpoises, population estimates within lower Cook 
Inlet yield low density estimates. Still, at even very low densities, 
it is possible to encounter these marine mammals during BlueCrest 
operations, as evidenced by the 2013 marine mammal sighting data. 
Marine mammals may approach the drilling rig out of curiosity, and 
animals may approach in a group. Thus, requested take authorizations 
for these species are primarily based on average group size, the 
potential for attraction, and the 2013 marine mammal sighting data 
(with buffers added in to account for missed sightings).
    Table 7 outlines density estimates, number of NMFS' proposed Level 
B harassment takes, the abundance of each species in Cook Inlet, the 
percentage of each species or stock estimated to be taken, and current 
population trends.

 Table 7--Density Estimates, Proposed Number of Level B Harassment Takes Species or Stock Abundance, Percentage of Population Proposed To Be Taken, and
                                                                  Species Trend Status
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Proposed Level                               Percentage of
              Species                   Density (#/km\2\)        B takes            Abundance              population                   Trend
--------------------------------------------------------------------------------------------------------------------------------------------------------
Beluga whale.......................  See Table 4...........               5  312...................  1.6...................  Decreasing.
Gray whale.........................  9.46E-05..............               5  19,126................  <0.1..................  Stable/increasing.
Harbor Seal........................  0.2769................              53  22,900................  0.2...................  Stable.
Harbor Porpoise....................  0.0042................              15  31,046................  0.1...................  No reliable information.
Killer Whale.......................  0.0008................              15  2,347 (resident);       0.6 (resident); 2.6     Resident stock possibly
                                                                              587(transient).         (transient).            increasing; Transient
                                                                                                                              stock stable.
Steller sea lion...................  0.0091................              25  55,422................  0.1...................  Decreasing with regional
                                                                                                                              variability (some
                                                                                                                              increasing or stable).
Minke whale........................  1.14E-05..............               5  1,233.................  0.4...................  No reliable information.
Humpback whale.....................  0.0012................              15  10,103................  0.2...................  Southeast Alaska
                                                                                                                              increasing.
Dall's porpoise....................  0.0002................              25  83,400................  0.3...................  No reliable information.
--------------------------------------------------------------------------------------------------------------------------------------------------------

Analysis and Preliminary Determinations

Negligible Impact

    Negligible impact is ``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 Level B harassment 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 behavioral harassment, 
NMFS must consider other factors, such as the likely nature of any 
responses (their intensity, duration, etc.), the context of any 
responses (critical reproductive time or location, feeding, migration, 
etc.), as well as the number and nature of estimated Level A harassment 
takes, the number of estimated mortalities, effects on habitat, and the 
status of the species. To avoid repetition, the discussion of our 
analyses applies to all the species listed in Table 7, given that the 
anticipated effects of this project on marine mammals are expected to 
be relatively similar in nature. There is no information about the 
size, status, or structure of any species or stock that

[[Page 35574]]

would lead to a different analysis for this activity, except where 
species-specific factors are identified and analyzed.
    No injuries or mortalities are anticipated to occur as a result of 
BlueCrest's proposed drilling program, and none are proposed to be 
authorized. Injury, serious injury, or mortality could occur if there 
were a large or very large oil spill. However, as discussed previously 
in this document, the likelihood of a spill is discountable. BlueCrest 
has implemented many design and operational standards to mitigate the 
potential for an oil spill of any size. NMFS does not propose to 
authorize take from an oil spill, as it is not part of the specified 
activity. Additionally, animals in the area are not expected to incur 
hearing impairment (i.e., TTS or PTS) or non-auditory physiological 
effects. Instead, any impact that could result from BlueCrest's 
activities is most likely to be behavioral harassment and is expected 
to be of limited duration. The marine mammals estimated to be taken 
represent small percentages of their respective species or stocks.
    The proposed drilling program does not fall within critical habitat 
designated in Cook Inlet for beluga whales or within critical habitat 
designated for Steller sea lions. The Cosmopolitan State unit is nearly 
100 mi south of beluga whale Critical Habitat Area 1 and approximately 
27 mi south of Critical Habitat Area 2. It is also located about 25 mi 
north of the isolated patch of Critical Habitat Area 2 found in 
Kachemak Bay. Area 2 is based on dispersed fall and winter feeding and 
transit areas in waters where whales typically appear in smaller 
densities or deeper waters (76 FR 20180, April 11, 2011). During the 
proposed period of operations, the majority of Cook Inlet beluga whales 
will be in Critical Habitat Area 1, well north of the proposed drilling 
area. The proposed activities are not anticipated to adversely affect 
beluga whale critical habitat, and mitigation measures and safety 
protocols are in place to reduce any potential even further.
    Sound levels emitted during the proposed activity are anticipated 
to be low overall with the exception of impact hammering and VSP 
operations. The continuous sounds produced by the drill rig do not rise 
to the level thought to cause take in marine mammals. Additionally, 
impact hammering and airgun operations will occur for extremely limited 
time periods (for a few hours at a time for 1-3 days and for a few 
hours at a time for 1-2 days, respectively). Moreover, auditory injury 
has not been noted in marine mammals from these activities. Mitigation 
measures proposed for inclusion in any issued IHA will reduce these 
potentials even further.
    The addition of the jack-up rig and a few support vessels and sound 
due to rig and vessel operations associated with the drilling program 
would not be outside the present experience of marine mammals in Cook 
Inlet, although levels may increase locally. Given the large number of 
vessels in Cook Inlet and the apparent habituation to vessels by Cook 
Inlet marine mammals that may occur in the area, vessel activity and 
sound is not expected to have effects that could cause significant or 
long-term consequences for individual marine mammals or their 
populations.
    Potential impacts to marine mammal habitat were discussed 
previously in this document (see the ``Anticipated Effects on Habitat'' 
section). Although some disturbance is possible to food sources of 
marine mammals, the impacts are anticipated to be minor enough as to 
not affect annual rates of recruitment or survival of marine mammals in 
the area. Based on the size of Cook Inlet where feeding by marine 
mammals occurs versus the localized area of drilling program 
activities, any missed feeding opportunities in the direct project area 
would be minor based on the fact that other feeding areas exist 
elsewhere nearby. Additionally, the direct project area is not within 
in the primary beluga feeding and calving habitat.
    Taking into account the mitigation measures that are planned, 
effects on marine mammals are generally expected to be restricted to 
avoidance of a limited area around the drilling operation and short-
term changes in behavior, falling within the MMPA definition of ``Level 
B harassment.'' Animals are not expected to permanently abandon any 
area that is part of the drilling operations, and any behaviors that 
are interrupted during the activity are expected to resume once the 
activity ceases. Only a small portion of marine mammal habitat will be 
affected at any time, and other areas within Cook Inlet will be 
available for necessary biological functions. Based on the analysis 
contained herein of the likely effects of the specified activity on 
marine mammals and their habitat, and taking into consideration the 
implementation of the proposed monitoring and mitigation measures, NMFS 
preliminarily finds that the total marine mammal take from BlueCrest's 
proposed drilling program will not adversely affect annual rates of 
recruitment or survival, and therefore will have a negligible impact on 
the affected marine mammal species or stocks.

Small Numbers

    The requested takes proposed to be authorized for each species are 
presented in Table 7 above. The proposed authorized takes for each 
species represent percentages ranging from <0.1 up to 1.6 of the 
respective stock population estimates for each species. These estimates 
represent the percentage of each species or stock that could be taken 
by Level B behavioral harassment if each animal is taken only once. The 
numbers of marine mammals taken are small relative to the affected 
species or stock sizes. In addition, the mitigation and monitoring 
measures (described previously in this document) proposed for inclusion 
in the IHA (if issued) are expected to reduce even further any 
potential disturbance to marine mammals. NMFS preliminarily finds that 
small numbers of marine mammals will be taken relative to the 
populations of the affected species or stocks.

Impact on Availability of Affected Species for Taking for Subsistence 
Uses

Relevant Subsistence Uses

    The subsistence harvest of marine mammals transcends the 
nutritional and economic values attributed to the animal and is an 
integral part of the cultural identity of the region's Alaska Native 
communities. Inedible parts of the whale provide Native artisans with 
materials for cultural handicrafts, and the hunting itself perpetuates 
Native traditions by transmitting traditional skills and knowledge to 
younger generations (NOAA, 2007).
    The Cook Inlet beluga whale has traditionally been hunted by Alaska 
Natives for subsistence purposes. For several decades prior to the 
1980s, the Native Village of Tyonek residents were the primary 
subsistence hunters of Cook Inlet beluga whales. During the 1980s and 
1990s, Alaska Natives from villages in the western, northwestern, and 
North Slope regions of Alaska either moved to or visited the south 
central region and participated in the yearly subsistence harvest 
(Stanek, 1994). From 1994 to 1998, NMFS estimated 65 whales per year 
(range 21-123) were taken in this harvest, including those successfully 
taken for food and those struck and lost. NMFS has concluded that this 
number is high enough to account for the estimated 14 percent annual 
decline in the population during this time (Hobbs et al., 2008). Actual 
mortality may have been higher, given the difficulty of

[[Page 35575]]

estimating the number of whales struck and lost during the hunts. In 
1999, a moratorium was enacted (Public Law 106-31) prohibiting the 
subsistence take of Cook Inlet beluga whales except through a 
cooperative agreement between NMFS and the affected Alaska Native 
organizations. Since the Cook Inlet beluga whale harvest was regulated 
in 1999 requiring cooperative agreements, five beluga whales have been 
struck and harvested. Those beluga whales were harvested in 2001 (one 
animal), 2002 (one animal), 2003 (one animal), and 2005 (two animals). 
The Native Village of Tyonek agreed not to hunt or request a hunt in 
2007, when no co-management agreement was to be signed (NMFS, 2008a).
    On October 15, 2008, NMFS published a final rule that established 
long-term harvest limits on Cook Inlet beluga whales that may be taken 
by Alaska Natives for subsistence purposes (73 FR 60976). That rule 
prohibits harvest for a 5-year interval period if the average stock 
abundance of Cook Inlet beluga whales over the prior five-year interval 
is below 350 whales. Harvest levels for the current 5-year planning 
interval (2013-2017) are zero because the average stock abundance for 
the previous five-year period (2008-2012) was below 350 whales. Based 
on the average abundance over the 2002-2007 period, no hunt occurred 
between 2008 and 2012 (NMFS, 2008a). The Cook Inlet Marine Mammal 
Council, which managed the Alaska Native Subsistence fishery with NMFS, 
was disbanded by a unanimous vote of the Tribes' representatives on 
June 20, 2012. At this time, no harvest is expected in 2016.
    Data on the harvest of other marine mammals in Cook Inlet are 
sparse. Some data are available on the subsistence harvest of harbor 
seals, harbor porpoises, and killer whales in Alaska in the marine 
mammal stock assessments. However, these numbers are for the Gulf of 
Alaska including Cook Inlet, and they are not indicative of the harvest 
in Cook Inlet.
    Some detailed information on the subsistence harvest of harbor 
seals is available from past studies conducted by the Alaska Department 
of Fish & Game (Wolfe et al., 2009). In 2008, only 33 harbor seals were 
taken for harvest in the Upper Kenai-Cook Inlet area. In the same 
study, reports from hunters stated that harbor seal populations in the 
area were increasing (28.6%) or remaining stable (71.4%). The specific 
hunting regions identified were Anchorage, Homer, Kenai, and Tyonek, 
and hunting generally peaks in March, September, and November (Wolfe et 
al., 2009). Since 1992, Alaska Natives from the Cook Inlet villages of 
Homer and Kenai have annually taken (harvested plus struck and lost) an 
average of 14-15 harbor seals. There are no data for Ninilchik alone. 
The villages are located between 14 mi (Ninilchik) and 50 mi (Kenai) 
away from the Cosmopolitan well site.

Potential Impacts to Subsistence Uses

    Section 101(a)(5)(D) also requires NMFS to determine that the 
authorization will not have an unmitigable adverse effect on the 
availability of marine mammal species or stocks for subsistence use. 
NMFS has defined ``unmitigable adverse impact'' in 50 CFR 216.103 as: 
an impact resulting from the specified activity: (1) That is likely to 
reduce the availability of the species to a level insufficient for a 
harvest to meet subsistence needs by: (i) Causing the marine mammals to 
abandon or avoid hunting areas; (ii) Directly displacing subsistence 
users; or (iii) Placing physical barriers between the marine mammals 
and the subsistence hunters; and (2) That cannot be sufficiently 
mitigated by other measures to increase the availability of marine 
mammals to allow subsistence needs to be met.
    The primary concern is the disturbance of marine mammals through 
the introduction of anthropogenic sound into the marine environment 
during the proposed drilling program. Marine mammals could be 
behaviorally harassed and either become more difficult to hunt or 
temporarily abandon traditional hunting grounds. If a large or very 
large oil spill occurred, it could impact subsistence species. However, 
as previously mentioned, oil spill is not anticipated to occur (nor 
authorized), and measures have been taken to prevent a large or very 
large oil spill. Oil spill trajectory scenarios developed in 
preparation of the ODPCP indicate that potential spills would travel 
south through the central channel of Cook Inlet, away from shoreline 
subsistence harvest areas. The proposed drilling program should not 
have any impacts to beluga harvests as none currently occur in Cook 
Inlet. Additionally, subsistence harvests of other marine mammal 
species are limited in Cook Inlet and typically occur in months when 
the proposed drilling program would not operate.
    The proposed mitigation measures described earlier in this document 
will reduce impacts to any hunts of harbor seals or other marine mammal 
species that may occur in Cook Inlet. These measures will ensure that 
marine mammals are available to subsistence hunters.

Unmitigable Adverse Impact Analysis and Preliminary Determination

    The project will not have any effect on current beluga whale 
harvests because no beluga harvest will take place in 2016. 
Additionally, the proposed drilling area is not an important native 
subsistence site for other subsistence species of marine mammals. Also, 
because of the relatively small proportion of marine mammals utilizing 
Cook Inlet, the number harvested in any future hunts would be expected 
to be extremely low. Therefore, because the proposed program would 
result in only temporary disturbances, the drilling program would not 
impact the availability of these other marine mammal species for 
subsistence uses.
    The timing and location of subsistence harvest of Cook Inlet harbor 
seals may coincide with BlueCrest's project late in the proposed 
drilling season, but because this subsistence hunt is conducted 
opportunistically and at such a low level (NMFS, 2013c), BlueCrest's 
program is not expected to have an impact on the subsistence use of 
harbor seals.
    NMFS anticipates that any effects from BlueCrest's proposed 
drilling program on marine mammals, especially harbor seals and Cook 
Inlet beluga whales, which are or have been taken for subsistence uses, 
would be short-term, site specific, and limited to inconsequential 
changes in behavior. NMFS does not anticipate that the authorized 
taking of affected species or stocks will reduce the availability of 
the species to a level insufficient for a harvest to meet subsistence 
needs by: (1) Causing the marine mammals to abandon or avoid hunting 
areas; (2) directly displacing subsistence users; or (3) placing 
physical barriers between the marine mammals and the subsistence 
hunters; and that cannot be sufficiently mitigated by other measures to 
increase the availability of marine mammals to allow subsistence needs 
to be met. In the unlikely event of a major oil spill in Cook Inlet, 
there could be major impacts on the availability of marine mammals for 
subsistence uses. As discussed earlier in this document, the 
probability of a major oil spill occurring over the life of the project 
is low. Additionally, BlueCrest developed an ODPCP. Based on the 
description of the specified activity, the measures described to 
minimize adverse effects on the availability of marine mammals for 
subsistence purposes, and the proposed mitigation and monitoring 
measures, NMFS has preliminarily determined that there will not be an 
unmitigable

[[Page 35576]]

adverse impact on marine mammal availability for taking for subsistence 
uses from BlueCrest's proposed activities.

Endangered Species Act (ESA)

    Cook Inlet beluga whales are listed as endangered under the ESA. 
The U.S. Army Corps of Engineers consulted with NMFS on an earlier 
version of this proposed project pursuant to section 7 of the ESA. On 
April 25, 2013, NMFS concurred with the conclusion that the proposed 
exploratory drilling program in lower Cook Inlet is not likely to 
adversely affect beluga whales, beluga whale critical habitat, or 
Steller sea lion critical habitat. However, due to the monitoring 
conducted at the well site in 2013, NMFS concluded that Section 7 
consultation is necessary, as listed species, particularly Steller sea 
lions, humpback whales, and belugas, may be affected. Therefore, NMFS 
is undertaking consultation pursuant to section 7 of the ESA as part of 
this activity.

National Environmental Policy Act (NEPA)

    NMFS has prepared a Programmatic Draft Environmental Assessment 
(EA) for issuance of IHAs for oil and gas activities in Cook Inlet for 
the 2016 open water season (including BlueCrest's activities). The 
Draft EA was made available for public comment in February, 2016 (81 FR 
12474). Public comments received on the Draft EA w will either be 
incorporated into the final EA and a Finding of No Significant Impact 
(FONSI) will be issued, or an Environmental Impact Statement (EIS) will 
be prepared prior to issuance of the IHA (if issued).

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to BlueCrest for conducting an oil and gas production 
drilling program in lower Cook Inlet during the 2016 open water season, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated. The proposed IHA language is provided 
next.
    This section contains a draft of the IHA itself. The wording 
contained in this section is proposed for inclusion in the IHA (if 
issued).
    1. This IHA is valid from August 1, 2016 through June 30, 2017.
    2. This IHA is valid only for activities associated with 
BlueCrest's lower Cook Inlet oil and gas production drilling program. 
The specific areas where BlueCrest's drilling operations will occur are 
described in the April, 2016 IHA application and depicted in Figure 1 
of the application.
    3. Species Authorized and Level of Take
    The incidental taking of marine mammals, by Level B harassment 
only, is limited to the following species in the waters of Cook Inlet:

------------------------------------------------------------------------
                                                             Number of
          Common name                Scientific name           takes
------------------------------------------------------------------------
Odontocetes:
    Beluga whale...............  Delphinapterus leucas..               5
    Harbor porpoise............  Phocoena phocoena......              15
    Dall's porpoise............  Phocoenoides dalli.....              25
    Killer whale...............  Orcinus orca...........              15
Mysticetes:
    Gray whale.................  Eschrichtius robustus..               5
    Minke whale................  Balaenoptera                          5
                                  acutorostra.
    Humpback whale.............  Megaptera novaeangliae.              15
Pinnipeds:
    Harbor seal................  Phoca vitulina                       53
                                  richardii.
    Steller sea lion...........  Eumetopias jubatus.....              25
------------------------------------------------------------------------

    If any marine mammal species not listed above are encountered 
during operations and are likely to be exposed to sound pressure levels 
(SPLs) greater than or equal to 160 dB re 1 [mu]Pa (rms) for impulse 
sources or greater than or equal to 120 dB re 1 [mu]Pa (rms), then the 
Holder of this IHA must shut-down the sound source prior to the animal 
entering the applicable Level B isopleth to avoid take.
    4. The authorization for taking by harassment is limited to the 
following acoustic sources (or sources with comparable frequency and 
intensity) and from the following activities:
    a. Airgun array with a total discharge volume of 720 in\3\; and
    b. impact hammer during drive pipe driving.
    5. The taking of any marine mammal in a manner prohibited under 
this IHA must be reported immediately to the Chief, Permits and 
Conservation Division, Office of Protected Resources, NMFS or her 
designee.
    6. The holder of this IHA must notify the Chief of the Permits and 
Conservation Division, Office of Protected Resources, as well as the 
Field Supervisor of the Protected Resources Division in the Alaska 
Regional Office at least 48 hours prior to the start of exploration 
drilling activities (unless constrained by the date of issuance of this 
IHA in which case notification shall be made as soon as possible).
    7. Mitigation and Monitoring Requirements: The Holder of this IHA 
is required to implement the following mitigation and monitoring 
requirements when conducting the specified activities to achieve the 
least practicable impact on affected marine mammal species or stocks:
    a. Utilize at least two qualified, vessel-based Protected Species 
Observers (PSOs) to visually watch for and monitor marine mammals near 
the drill rig during specified activities below (drive pipe hammering 
and VSP activities) before and during start-ups of sound sources day or 
night, allowing for one PSO to be on-duty while the other is off duty. 
PSOs shall have access to reticle binoculars, big-eye binoculars, and 
night vision devices. PSO shifts shall last no longer than 4 hours at a 
time. PSOs shall also make observations during daytime periods when the 
sound sources are not operating for comparison of animal abundance and 
behavior, when feasible. When practicable, as an additional means of 
visual observation, drill rig or vessel crew may also assist in 
detecting marine mammals.
    b. When a mammal sighting is made, the following information about 
the sighting will be recorded:
    i. Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from the PSO, apparent reaction to 
activities (e.g., none,

[[Page 35577]]

avoidance, approach, paralleling, etc.), closest point of approach, and 
behavioral pace;
    ii. Time, location, speed, activity of the vessel, sea state, ice 
cover, visibility, and sun glare;
    iii. The positions of other vessel(s) in the vicinity of the PSO 
location (if applicable);
    iv. The rig's position and water depth, sea state, ice cover, 
visibility, and sun glare will also be recorded at the start and end of 
each observation watch, every 30 minutes during a watch, and whenever 
there is a change in any of those variables.
    c. Within safe limits, the PSOs should be stationed where they have 
the best possible viewing;
    d. PSOs should be instructed to identify animals as unknown where 
appropriate rather than strive to identify a species if there is 
significant uncertainty;
    e. Drive Pipe Hammering Mitigation Measures:
    i. PSOs will observe from the drill rig during impact hammering out 
to the 160 dB (rms) radius of 1.6 km (1 mi). If marine mammal species 
for which take is not authorized, or if any listed species (beluga 
whales, humpback whales, or Steller sea lions) are about to enter this 
zone, then use of the impact hammer must cease.
    ii. If cetaceans approach or enter within the 180 dB (rms) radius 
of 250 m (820 ft) or if pinnipeds approach or enter within the 190 dB 
(rms) radius of 60 m (200 ft), then use of the impact hammer must 
cease. Following a shutdown of impact hammering activities, the 
applicable zones must be clear of marine mammals for at least 30 
minutes prior to restarting activities.
    iii. PSOs will visually monitor out to the 160 dB radius for at 
least 30 minutes prior to the initiation of activities. If no marine 
mammals are detected during that time, then BlueCrest can initiate 
impact hammering using a ``soft start'' technique. Hammering will begin 
with an initial set of three strikes at 40 percent energy followed by a 
1 min waiting period, then two subsequent three-strike sets. This 
``soft-start'' procedure will be implemented anytime impact hammering 
has ceased for 30 minutes or more. Impact hammer ``soft-start'' will 
not be required if the hammering downtime is for less than 30 minutes 
and visual surveys are continued throughout the silent period, and no 
marine mammals are observed in the applicable zones during that time.
    f. VSP Airgun Mitigation Measures:
    i. PSOs will observe from the drill rig during airgun operations 
out to the 160 dB radius of 2.5 km (1.55 mi). If marine mammal species 
for which take is not authorized, or if any listed species (beluga 
whales, humpback whales, or Steller sea lions) are about to enter this 
zone, then use of the airguns will cease.
    ii. If cetaceans approach or enter within the 180 dB (rms) radius 
of 240 m (787 ft) or if pinnipeds approach or enter within the 190 dB 
(rms) radius of 120 m (394 ft), then use of the airguns will cease. 
Following a shutdown of airgun operations, the applicable zones must be 
clear of marine mammals for at least 30 minutes prior to restarting 
activities.
    iii. PSOs will visually monitor out to the 160 dB radius for at 
least 30 minutes prior to the initiation of activities. If no marine 
mammals are detected during that time, then BlueCrest can initiate 
airgun operations using a ``ramp-up'' technique. Airgun operations will 
begin with the firing of a single airgun, which will be the smallest 
gun in the array in terms of energy output (dB) and volume (in\3\). 
Operators will then continue ramp-up by gradually activating additional 
airguns over a period of at least 30 minutes (but not longer than 40 
minutes) until the desired operating level of the airgun array is 
obtained. This ramp-up procedure will be implemented anytime airguns 
have not been fired for 30 minutes or more. Airgun ramp-up will not be 
required if the airguns have been off for less than 10 minutes and 
visual surveys are continued throughout the silent period, and no 
marine mammals are observed in the applicable zones during that time.
    g. No initiation of survey operations involving the use of sound 
sources is permitted from a shutdown position at night or during low-
light hours (such as in dense fog or heavy rain).
    h. During rig towing operations, speed will be reduced to 8 knots 
or less, as safety allows, at the approach of any whales or Steller sea 
lions within 2,000 ft (610 m) of the towing operations.
    i. Helicopters must maintain an altitude of at least 1,000 ft (305 
m), except during takeoffs, landings, or emergency situations.
    8. Reporting Requirements: The Holder of this IHA is required to:
    a. Submit a draft Technical Report on all activities and monitoring 
results to NMFS' Permits and Conservation Division within 90 days of 
expiration of the IHA. The Technical Report will include:
    i. Summaries of monitoring effort (total hours, total distances, 
and marine mammal distribution through the study period, accounting for 
sea state and other factors affecting visibility and detectability of 
marine mammals);
    ii. Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare);
    iii. Species composition, occurrence, and distribution of marine 
mammal sightings, including date, water depth, numbers, age/size/gender 
categories (if determinable), group sizes, and ice cover;
    iv. Analyses of the effects of the proposed project activities on 
marine mammal behaviors;
    v. Sighting rates of marine mammals during periods with and without 
drilling operation activities (and other variables that could affect 
detectability), such as: (A) Initial sighting distances versus activity 
state; (B) closest point of approach versus activity state; (C) 
observed behaviors and types of movements versus activity state; (D) 
numbers of sightings/individuals seen versus activity state; (E) 
distribution around the drill rig versus activity state; and (F) 
estimates of take by Level B harassment based on presence in the 120 dB 
and 160 dB harassment zones.
    b. Submit a final report to the Chief, Permits and Conservation 
Division, Office of Protected Resources, NMFS, within 30 days after 
receiving comments from NMFS on the draft technical report. If NMFS has 
no comments on the draft technical report, the draft report shall be 
considered to be the final report.
    9.a. In the unanticipated event that BlueCrest's specified activity 
clearly causes the take of a marine mammal in a manner prohibited by 
this IHA, such as an injury (Level A harassment), serious injury, or 
mortality (e.g., ship-strike, gear interaction, and/or entanglement), 
BlueCrest shall immediately cease the specified activities and 
immediately report the incident to the Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, her 
designees, the Alaska Region Protected Resources Division, NMFS, and 
the Alaska Regional Stranding Coordinators. The report must include the 
following information:
    i. Time, date, and location (latitude/longitude) of the incident;
    ii. The name and type of vessel involved;
    iii. The vessel's speed during and leading up to the incident;
    iv. Description of the incident;
    v. Status of all sound source use in the 24 hours preceding the 
incident;
    vi. Water depth;
    vii. Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);

[[Page 35578]]

    viii. Description of marine mammal observations in the 24 hours 
preceding the incident;
    ix. Species identification or description of the animal(s) 
involved;
    x. The fate of the animal(s); and
    xi. Photographs or video footage of the animal (if equipment is 
available).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with BlueCrest to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. BlueCrest may not resume 
their activities until notified by NMFS via letter or email, or 
telephone.
    b. In the event that BlueCrest discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition as described in the next paragraph), 
BlueCrest will immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
her designees, the Alaska Region Protected Resources Division, NMFS, 
and the NMFS Alaska Stranding Hotline. The report must include the same 
information identified in the Condition 9(a) above. If the observed 
marine mammal is dead, activities may continue while NMFS reviews the 
circumstances of the incident. If the observed marine mammal is 
injured, measures described in Condition 10 below must be implemented. 
NMFS will work with BlueCrest to determine whether modifications in the 
activities are appropriate.
    c. In the event that BlueCrest discovers an injured or dead marine 
mammal, and the lead PSO determines that the injury or death is not 
associated with or related to the activities authorized in Condition 2 
of this IHA (e.g., carcass with moderate to advanced decomposition or 
scavenger damage), BlueCrest shall report the incident to the Chief of 
the Permits and Conservation Division, Office of Protected Resources, 
NMFS, her designees, the Alaska Region Protected Resources Division, 
NMFS, the NMFS Alaska Stranding Hotline (1-877-925-7773), and the 
Alaska Regional Stranding Coordinators within 24 hours of the 
discovery. BlueCrest shall provide photographs or video footage (if 
available) or other documentation of the stranded animal sighting to 
NMFS and the Marine Mammal Stranding Network. If the observed marine 
mammal is dead, activities may continue while NMFS reviews the 
circumstances of the incident. If the observed marine mammal is 
injured, measures described in Condition 10 below must be implemented. 
In this case, NMFS will notify BlueCrest when activities may resume.
    10. The following measures describe the specific actions BlueCrest 
must take if a live marine mammal stranding is reported in Cook Inlet 
coincident to, or within 72 hours of seismic survey activities 
involving the use of airguns. A live stranding event is defined as a 
marine mammal: (i) On a beach or shore of the United States and unable 
to return to the water; (ii) on a beach or shore of the United States 
and, although able to return to the water, is in apparent need of 
medical attention; or (iii) in the waters under the jurisdiction of the 
United States (including navigable waters) but is unable to return to 
its natural habitat under its own power or without assistance.
    a. Should BlueCrest become aware of a live stranding event (from 
NMFS or another source), BlueCrest must immediately implement a 
shutdown of the airgun array.
    i. A shutdown must be implemented whenever the animal is within 5 
km of the seismic airguns.
    ii. Shutdown procedures will remain in effect until NMFS determines 
that, and advises BlueCrest that, all live animals involved in the 
stranding have left the area (either of their own volition or following 
herding by responders).
    b. Within 48 hours of the notification of the live stranding event, 
BlueCrest must inform NMFS where and when they were operating airguns 
and at what discharge volumes.
    c. BlueCrest must appoint a contact who can be reached 24/7 for 
notification of live stranding events. Immediately upon notification of 
the live stranding event, this person must order the immediate shutdown 
of the airguns.
    d. These conditions are in addition to Condition 9.
    11. Activities related to the monitoring described in this IHA do 
not require a separate scientific research permit issued under section 
104 of the MMPA.
    12. A copy of this IHA must be in the possession of all contractors 
and PSOs operating under the authority of this IHA.
    13. Penalties and Permit Sanctions: Any person who violates any 
provision of this IHA is subject to civil and criminal penalties, 
permit sanctions, and forfeiture as authorized under the MMPA.
    14. This IHA may be modified, suspended or withdrawn if the Holder 
fails to abide by the conditions prescribed herein or if NMFS 
determines the authorized taking is having more than a negligible 
impact on the species or stock of affected marine mammals, or if there 
is an unmitigable adverse impact on the availability of such species or 
stocks for subsistence uses.

Request for Public Comments

    NMFS requests comment on our analysis, the draft authorization, and 
any other aspect of the Notice of Proposed IHA for BlueCrest's proposed 
lower Cook Inlet oil and gas production drilling program. Please 
include with your comments any supporting data or literature citations 
to help inform our final decision on BlueCrest's request for an MMPA 
authorization.

    Dated: May 26, 2016.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2016-12886 Filed 6-1-16; 8:45 am]
 BILLING CODE 3510-22-P