Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Bluecrest Alaska Operating LLC Drilling Activities in Lower Cook Inlet, 2015, 54397-54427 [2014-21662]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 79, Number 176 (Thursday, September 11, 2014)]
[Notices]
[Pages 54397-54427]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-21662]



[[Page 54397]]

Vol. 79

Thursday,

No. 176

September 11, 2014

Part III





Department of Commerce





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National Oceanic and Atmospheric Administration





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Takes of Marine Mammals Incidental to Specified Activities; Taking 
Marine Mammals Incidental to Bluecrest Alaska Operating LLC Drilling 
Activities in Lower Cook Inlet, 2015; Notice

Federal Register / Vol. 79 , No. 176 / Thursday, September 11, 2014 / 
Notices

[[Page 54398]]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XD429


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Bluecrest Alaska Operating LLC 
Drilling Activities in Lower Cook Inlet, 2015

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 offshore exploratory drilling program in lower Cook Inlet, AK, 
during the 2015 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 October 
14, 2014.

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.Nachman@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 Environmental 
Assessment (EA), and a list of the references used in this document may 
be obtained by writing to the address specified above, telephoning the 
contact listed below (see FOR FURTHER INFORMATION CONTACT), or visiting 
the internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. 
Documents cited in this notice may also be viewed, by appointment, 
during regular business hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Candace Nachman, 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 June 30, 2014, NMFS received an IHA application from Bluecrest 
for the taking of marine mammals incidental to an offshore exploratory 
drilling program in lower Cook Inlet, AK, during the 2015 open water 
season (typically mid-April through October). Although Bluecrest's 
application indicates that the drilling program could begin as early as 
fall 2014, subsequent communications from Bluecrest note that drilling 
will not begin before April 1, 2015. NMFS determined that the 
application was adequate and complete on July 16, 2014.
    Bluecrest proposes to drill one exploratory well at Cosmopolitan 
State B-1 site during the 2015 open-water season, which is 
typically from April through October. Depending on the results, 
Bluecrest will evaluate future (2016-2018) potential oil and/or gas 
activities at both the Cosmopolitan State A-1 and B-1 
locations. The following specific aspects of the proposed activities 
are likely to result in the take of marine mammals: Driving of the 
conductor pipe; exploratory drilling; towing of the jack-up drill rig; 
and vertical seismic profiling (VSP). Take, by Level B harassment only, 
of six marine mammal species is anticipated to result from the 
specified activity.

Description of the Specified Activity

Overview

    Bluecrest proposes to conduct exploratory drilling operations at 
one well site in lower Cook Inlet during the 2015 open water (ice-free) 
season (i.e., April through October), using the Endeavour-Spirit of 
Independence (Endeavour) jack-up drill rig or the Spartan 151 jack-up 
drill rig, depending on availability. The rig will be towed to the 
drilling site by ocean-going tugs. The activities of relevance to this 
IHA request include: Mobilization and demobilization of the drill rig 
to and from the well location at the start and end of the season; 
driving of the conductor pipe; exploratory drilling; and VSP seismic 
operations. Bluecrest proposes to utilize both helicopters and vessels 
to conduct resupply, crew change, and other logistics during the 
exploratory drilling program.

Dates and Duration

    The 2015 exploratory drilling program (which is the subject of this 
IHA request) would occur during the 2015 open water season 
(approximately April 15 through October 31). Bluecrest estimates that 
the drilling period could extend up to 90 days, including up to 15 days 
of well testing. During this time period, conductor pipe driving would 
only occur for a period of 1 to 3 days (although actual sound 
generation would occur only intermittently during this time period), 
and VSP seismic

[[Page 54399]]

operations would only occur for a period of less than 1 to 2 days. 
Mobilization and demobilization rig tows are estimated to take less 
than 24 hours. This IHA (if issued) would be effective for 1 year, 
beginning on or around April 1, 2015.

Specified Geographic Region

    Bluecrest's proposed program would occur at Cosmopolitan State 
B-1 (originally Cosmopolitan 2) in lower Cook Inlet, 
AK. The exact well location is latitude 59[deg]52'13.887'' N., 
151[deg]52'17.225'' W. in water depth of 61 ft. The exact location of 
Bluecrest's well site can be seen in Figure 1 in the IHA application.

Detailed Description of Activities

1. Drill Rig Mobilization and Towing
    Bluecrest proposes to conduct the exploratory drilling program 
using the Endeavour, which is an independent leg, cantilevered jack-up 
drill rig of the Marathon LeTourneau Class 116-C and is capable of 
drilling up to 25,000 ft in water depths from 15-300 ft. Additional 
specifications can be found in Appendix A of the IHA application. If 
the Endeavour is unavailable, Bluecrest would utilize the Spartan 151 
to conduct the exploratory drilling program. The Spartan 151 is a 150 H 
class indepent 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.
    As of July 2014, the Endeavour is moored at Port Graham where it is 
undergoing maintenance and winterization. The intention is to move the 
drill rig to the Cosmopolitan State B-1 well site in April 
2015, a distance of about 31 mi. If the Spartan 151 is used it will 
likely come from a well site location in upper Cook Inlet approximately 
62 mi north of Cosmopolitan State B-1. Tows from either 
location would likely be accomplished within a 24-hour period.
    The rig will be wet-towed by two or three ocean-going tugs licensed 
to operate in Cook Inlet. 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). The distance to the 120-dB isopleth, assuming a 171 dB 
source, is 1,715 feet (523 meters) using Collins et al.'s (2007) 171-
18.4 Log(R)--0.00188 R spreading model developed from Cook Inlet. 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).
2. Conductor Pipe Driving
    A conductor 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. The pipe also facilitates the return of cuttings from the 
drill head. Conductor pipes are usually installed using drilling, pile 
driving, or a combination of these techniques. In offshore wells, the 
conductor pipe is also used as a foundation for the wellhead. Bluecrest 
proposes to drive approximately 200 ft (60 m) below mudline of 30-inch 
conductor pipe at Cosmopolitan State B-1 prior to drilling 
using a Delmar D62-22 impact hammer. This hammer has impact weight of 
13,640 pounds (6,200 kg) and reaches a 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 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 conductor pipe driving event 
is expected to last 1 to 3 days, although actual sound generation 
(pounding) would occur only intermittently during this period.
3. Exploratory Drilling and Standard Operation
    The jack-up drilling rig Endeavour's drilling platform and other 
noise-generating equipment is located above the sea's surface, and 
there is very little surface contact with the water compared to drill 
ships and semi-submersible drill rigs; therefore, lattice-legged jack-
up drill rigs are relatively quiet (Richardson et al., 1995a; Spence et 
al., 2007).
    The Spartan 151, the only other jack-up drilling rig operating in 
the Cook Inlet, was hydro-acoustically measured by Marine Acoustics, 
Inc. (2011) while operating in 2011. The survey results showed that 
continuous noise levels exceeding 120 dB re 1[mu]Pa extended out only 
164 ft (50 m), and that this sound was largely associated with the 
diesel engines used as hotel power generators.
    The Endeavour was hydro-acoustically tested during drilling 
activities by Illingworth and Rodkin (2014) in May 2013 while the rig 
was operating at Cosmopolitan A-1. The results from the sound 
source verification indicated that sound generated from drilling or 
generators were below ambient sound levels. The generators used on the 
Endeavour are mounted on pedestals specifically to reduce sound 
transfer through the infrastructure, and they are enclosed in an 
insulated engine room, which may have reduced further underwater sound 
transmission to levels below those generated by the Spartan 151. Also, 
as mentioned above, the lattice legs limit transfer of noise generated 
from the drilling table to the water.
    The sound source verification revealed that the submersed deep-well 
pumps that charge the fire-suppression system and cool the generators 
(in a closed water system) generate sound levels exceeding 120 dB re 
1[mu]Pa out a distance of approximately 984 ft (300 m). It was not 
clear at the time of measurements whether the sound was a direct result 
of the pumps or was from the systems discharge water falling 
approximately 40 ft (12 m) from the deck. Thus, after the falling water 
was enclosed in pipe extending below the water surface in an effort to 
reduce sound levels, the pump noise levels were re-measured in June 
2013 (Illingworth and Rodkin, 2014) with results indicating that piping 
the falling water had a slight effect on reducing underwater sound 
levels; nevertheless, the 120-dB radius still extended out to 853 ft 
(260 m) in certain directions. Thus, neither drilling operations nor 
running generators on the Endeavour drill rig generate underwater sound 
levels exceeding 120 dB re 1[mu]Pa. However, the Endeavour's submersed 
deep-well pumps generate continuous sound exceeding 120 dB re 1[mu]Pa 
to a maximum distance of 853 ft (260 m). Deep well pumps were not 
identified as a sound source by Marine Acoustics, Inc. (2011) during 
their acoustical testing of the Spartan 151.

[[Page 54400]]

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 VSP.
    Bluecrest intends to conduct VSP operations at the end of drilling 
the 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. 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).
    Illingworth and Rodkin (2014) measured the underwater sound levels 
associated with the 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. 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 104 harbor porpoise, 72 
harbor seals, 32 minke whales, 19 Dall's porpoise, 12 gray whales, and 
two killer whales between May and August (112 days of monitoring). 
Based on their seasonal patterns, gray whales are not likely to be 
encountered during spring but could be encountered in low numbers at 
other times of year. Minke whales have been considered migratory in 
Alaska (Allen and Angliss, 2014) but have recently been observed off 
Cape Starichkof and Anchor Point year-round. 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, it is 
unlikely that humpback whales would be encountered during the proposed 
project.
    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 has been decreasing at a rate of 0.6 percent annually 
between 2002 and 2012 (Allen and Angliss, 2014). One review of the 
status of the population indicated that there is an 80% chance that the 
population will decline further (Hobbs and Shelden, 2008).
    Regional variation in trends in 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;

[[Page 54401]]

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 June 26, 2014, NMFS published a 
notice if the Federal Register requesting comments on a petition to 
designate the Central North Pacific humpback whale stock as a DPS and 
to delist the DPS from the ESA (79 FR 36281).
    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 did not request take of beluga and humpback whales or 
Steller sea lions. Informal consultation pursuant to section 7 of the 
ESA was conducted for this project. The U.S. Army Corps of Engineers 
determined (and NMFS concurred) that the activity is not likely to 
adversely affect listed species or critical habitat based upon the 
nature of the activities and specific mitigation measures to ensure 
that take of these species or adverse habitat impacts are unlikely. 
This is discussed further in the ``Proposed Mitigation'' section later 
in this document.
    Sea otters also occur in Cook Inlet. However, sea otters are 
managed by the U.S. Fish and Wildlife Service and are therefore not 
considered further in this proposed IHA notice. Information summaries 
for the species for which take is requested is provided next.

Cetaceans

1. Killer Whales
    Two different killer whale stocks inhabit the Cook Inlet region of 
Alaska: the Alaska resident stock and the Gulf of Alaska, Aleutian 
Islands, Bering Sea 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).
2. Harbor Porpoise
    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. 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 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.
3. Gray Whale
    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).
    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.
4. Minke Whale
    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.
5. Dall's Porpoise
    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 have been observed in 
lower Cook Inlet, including Kachemak Bay and near Anchor Point (Glenn 
Johnson, pers. comm.), but sightings there are rare. There is only the 
remote chance that Dall's porpoise might be observed during Bluecrest's 
proposed drilling program.

[[Page 54402]]

Pinnipeds

1. Harbor Seals
    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). Harbor seals may 
be encountered during Bluecrest's lower Cook Inlet proposed drilling 
program.

Summary

    As mentioned previously, take of marine mammals listed under the 
ESA is unlikely to occur because of mitigation measures to ensure no 
take of those species. 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 2013 SAR is available on the Internet at: 
https://www.nmfs.noaa.gov/pr/sars/pdf/ak2013final.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., 
driving of the conductor pipe; exploratory drilling; towing of the 
jack-up drill rig; and VSP) have been observed to or are thought to 
impact marine mammals. This section may include a discussion of known 
effects that do not rise to the level of take (for example, with 
acoustics, we may include a discussion of studies that showed animals 
not reacting at all to sound or exhibiting barely measurable 
avoidance). The discussion may also include reactions that we consider 
to rise to the level of a take and those that we do not consider to 
rise to the level of a take. This section is intended as a background 
of potential effects and does not consider either the specific manner 
in which this activity will be carried out or the mitigation that will 
be implemented or how either of those will shape the anticipated 
impacts from this specific activity. 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 could result from 
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 sound produced by drilling activity, conductor pipe driving, and rig 
towing, as well as 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 
30 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 40 kHz.
    As mentioned previously in this document, six marine mammal species 
(five cetacean and one phocid pinniped) may occur in the exploratory 
drilling area of Bluecrest's lower Cook Inlet project. Of the five 
cetacean species likely to occur in the proposed project area and for 
which take is requested, two are classified as low-frequency cetaceans 
(i.e., minke and gray whales), one is classified as a mid-frequency 
cetacean (i.e., killer whale), 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

[[Page 54403]]

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.
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.
    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 exploratory 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 and other potentially important natural sounds such 
as surf and prey noise. There is little concern regarding masking near 
the jack-up rig during exploratory 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.
    This 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).

[[Page 54404]]

    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 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, especially if the 
detected disturbances appear minor. However, the consequences of 
behavioral modification have the potential to be biologically 
significant if the change affects growth, survival, or reproduction.
    Detailed studies regarding responses to anthropogenic sound have 
been conducted on humpback, gray, and bowhead whales and ringed seals. 
Less detailed data are available for some other species of baleen 
whales, sperm whales, small toothed whales, and sea otters. The 
following sub-sections provide examples of behavioral responses that 
provide an idea of the variability in behavioral responses that would 
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. This result however, 
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 exploratory drilling operations. In general, 
little or no response was observed in animals exposed at received 
levels from 90-120 dB re 1 [mu]Pa (rms). Probability of avoidance and 
other behavioral effects increased when received levels were from 120-
160 dB re 1 [mu]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

[[Page 54405]]

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 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 [mu]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 [mu]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 
[mu]Pa rms is estimated to be 1.53 mi (2.47 km). Baleen whales within 
those distances may show avoidance or other strong disturbance 
reactions to the airgun array. Subtle behavioral changes sometimes 
become evident at somewhat lower received levels, and recent studies 
have shown that some species of baleen whales, notably bowhead and 
humpback whales, at times show strong avoidance at received levels 
lower than 160-170 dB re 1 [mu]Pa rms.
    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 [mu]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

[[Page 54406]]

ensonified by airguns and have continued to increase in number despite 
successive years of anthropogenic activity in the area. Gray whales 
continued to migrate annually along the west coast of North America 
despite intermittent seismic exploration and much ship traffic in that 
area for decades (Appendix A in Malme et al., 1984). 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 the 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, 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 dolphin 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. 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 
quadrats 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

[[Page 54407]]

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 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 AHDs 
(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 (9 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

[[Page 54408]]

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 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 
exploratory drilling program, animals are not expected to be exposed to 
levels high enough or durations long enough to result in PTS.
    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

[[Page 54409]]

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 exploratory drilling program in Cook Inlet. However, 
several of the sound sources do not even emit sound levels at levels 
high enough to potentially even cause TTS.
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 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

[[Page 54410]]

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. Additionally, no 
beaked whale species occur in the proposed project area.
    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 exploratory drilling program. In addition, marine mammals 
that show 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 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 
exploratory drilling program.

Vessel Impacts

    Vessel activity and noise associated with vessel activity will 
temporarily increase in the action area during Bluecrest's exploratory 
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 the drilling of an 
exploratory well and associated activities in lower Cook Inlet during 
the 2015 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 or very large oil spill occurring during 
Bluecrest's proposed exploratory drilling program is remote. 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 of extremely low probability.
    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.

[[Page 54411]]

     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;
     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.
    Despite concluding that the risk of serious injury or mortality 
from an oil spill in this case is extremely remote because the 
likelihood of a large or very large oil spill occurring as a result of 
this proposed exploratory drilling program, NMFS has nonetheless 
evaluated the potential effects of an oil spill on marine mammals. 
While an oil spill is not a component of Bluecrest's specified activity 
for which NMFS is proposing to authorize take, nor is an oil spill 
likely, potential impacts on marine mammals from an oil spill (in the 
unlikely event that one occurs) are discussed in more detail next.
1. Potential Effects of Oil on Cetaceans
    The specific effects an oil spill would have on cetaceans are not 
well known. Exposure to spilled oil could lead to skin irritation, 
baleen fouling (which might reduce feeding efficiency), respiratory 
distress from inhalation of hydrocarbon vapors, consumption of some 
contaminated prey items, and temporary displacement from contaminated 
feeding areas. Geraci and St. Aubin (1990) summarize effects of oil on 
marine mammals. The number of cetaceans that might be contacted by a 
spill would depend on the size, timing, and duration of the spill and 
where the oil is in relation to the animals. Whales may not avoid oil 
spills, and some have been observed feeding within oil slicks (Goodale 
et al., 1981).
    There is no direct evidence that oil spills, including the much 
studied Santa Barbara Channel and Exxon Valdez spills, have caused any 
deaths of cetaceans (Geraci, 1990; Brownell, 1971; Harvey and Dahlheim, 
1994). It is suspected that some individually identified killer whales 
that disappeared from Prince William Sound during the time of the Exxon 
Valdez spill were casualties of that spill. However, no clear cause and 
effect relationship between the spill and the disappearance could be 
established (Dahlheim and Matkin, 1994). The AT-1 pod of transient 
killer whales that sometimes inhabits Prince William Sound has 
continued to decline after the Exxon Valdez oil spill (EVOS). Matkin et 
al. (2008) tracked the AB resident pod and the AT-1 transient group of 
killer whales from 1984 to 2005. The results of their photographic 
surveillance indicate a much higher than usual mortality rate for both 
populations the year following the spill (33% for AB Pod and 41% for 
AT-1 Group) and lower than average rates of increase in the 16 years 
after the spill (annual increase of about 1.6% for AB Pod compared to 
an annual increase of about 3.2% for other Alaska killer whale pods). 
In killer whale pods, mortality rates are usually higher for non-
reproductive animals and very low for reproductive animals and 
adolescents (Olesiuk et al., 1990, 2005; Matkin et al., 2005). No 
effects on humpback whales in Prince William Sound were evident after 
the EVOS (von Ziegesar et al., 1994). There was some temporary 
displacement of humpback whales out of Prince William Sound, but this 
could have been caused by oil contamination, boat and aircraft 
disturbance, displacement of food sources, or other causes.
    Migrating gray whales were apparently not greatly affected by the 
Santa Barbara spill of 1969. There appeared to be no relationship 
between the spill and mortality of marine mammals. The higher than 
usual counts of dead marine mammals recorded after the spill 
represented increased survey effort and therefore cannot be 
conclusively linked to the spill itself (Brownell, 1971; Geraci, 1990). 
The conclusion was that whales were either able to detect the oil and 
avoid it or were unaffected by it (Geraci, 1990).
    Schwake et al. (2013) studied two populations of common bottlenose 
dolphins in the Gulf of Mexico following the Deepwater Horizon oil 
spill to evaluate sublethal effects. They conducted health assessments 
in

[[Page 54412]]

Barataria Bay, Louisiana, an area that received heavy and prolonged 
oiling and in a reference site, Sarasota Bay, Florida, where oil was 
not observed. Several disease conditions were noted for the Barataria 
Bay dolphins, including hypoadrenocorticism, pulmonary abnormalities, 
and tooth loss (Schwake et al., 2013). Even though several of the 
observed health effects are consistent with exposure to petroleum 
hydrocarbons because the researchers did not have prespill health data 
for the Barataria Bay dolphins, they could not rule out that other pre-
existing environmental stressors made this population particularly 
vulnerable to effects from the oil spill (Schwake et al., 2013).
    Whales rely on a layer of blubber for insulation, so oil would have 
little if any effect on thermoregulation by whales. Effects of oiling 
on cetacean skin appear to be minor and of little significance to the 
animal's health (Geraci, 1990). Histological data and ultrastructural 
studies by Geraci and St. Aubin (1990) showed that exposures of skin to 
crude oil for up to 45 minutes in four species of toothed whales had no 
effect. They switched to gasoline and applied the sponge up to 75 
minutes. This produced transient damage to epidermal cells in whales. 
Subtle changes were evident only at the cell level. In each case, the 
skin damage healed within a week. They concluded that a cetacean's skin 
is an effective barrier to the noxious substances in petroleum. These 
substances normally damage skin by getting between cells and dissolving 
protective lipids. In cetacean skin, however, tight intercellular 
bridges, vital surface cells, and the extraordinary thickness of the 
epidermis impeded the damage. The authors could not detect a change in 
lipid concentration between and within cells after exposing skin from a 
white-sided dolphin to gasoline for 16 hours in vitro.
    Whales could ingest oil if their food is contaminated, or oil could 
also be absorbed through the respiratory tract. Some of the ingested 
oil is voided in vomit or feces but some is absorbed and could cause 
toxic effects (Geraci, 1990). When returned to clean water, 
contaminated animals can depurate this internal oil (Engelhardt, 1978, 
1982). Oil ingestion can decrease food assimilation of prey eaten (St. 
Aubin, 1988). Cetaceans may swallow some oil-contaminated prey, but it 
likely would be only a small part of their food. It is not known if 
whales would leave a feeding area where prey was abundant following a 
spill. Some zooplankton eaten by baleen whales consume oil particles, 
and bioaccumulation can result. Tissue studies by Geraci and St. Aubin 
(1990) revealed low levels of naphthalene in the livers and blubber of 
baleen whales. This result suggests that prey have low concentrations 
in their tissues, or that baleen whales may be able to metabolize and 
excrete certain petroleum hydrocarbons. However, baleen whale species 
are uncommon in the location of Bluecrest's proposed well site. Baleen 
whales are more likely to be encountered in the lower Inlet during rig 
towing, far away from the drill sites. Whales exposed to an oil spill 
are unlikely to ingest enough oil to cause serious internal damage 
(Geraci and St. Aubin, 1980, 1982), and this kind of damage has not 
been reported (Geraci, 1990).
    Some cetaceans can detect oil and sometimes avoid it, but others 
enter and swim through slicks without apparent effects (Geraci, 1990; 
Harvey and Dahlheim, 1994). Bottlenose dolphins in the Gulf of Mexico 
apparently could detect and avoid slicks and mousse but did not avoid 
light sheens on the surface (Smultea and Wursig, 1995). After the Regal 
Sword spill in 1979, various species of baleen and toothed whales were 
observed swimming and feeding in areas containing spilled oil southeast 
of Cape Cod, MA (Goodale et al., 1981). For months following EVOS, 
there were numerous observations of gray whales, harbor porpoises, 
Dall's porpoises, and killer whales swimming through light-to-heavy 
crude-oil sheens (Harvey and Dalheim, 1994, cited in Matkin et al., 
2008). However, if some of the animals avoid an area because of the 
oil, then the effects of the oiling would be less severe on those 
individuals.
2. Potential Effects of Oil on Pinnipeds
    Externally oiled phocid seals often survive and become clean, but 
heavily oiled seal pups and adults may die, depending on the extent of 
oiling and characteristics of the oil. Adult seals may suffer some 
temporary adverse effects, such as eye and skin irritation, with 
possible infection (MMS, 1996). Such effects may increase stress, which 
could contribute to the death of some individuals. There is a 
likelihood that newborn seal pups, if contacted by oil, would die from 
oiling through loss of insulation and resulting hypothermia.
    Reports of the effects of oil spills have shown that some mortality 
of seals may have occurred as a result of oil fouling; however, large 
scale mortality had not been observed prior to the EVOS (St. Aubin, 
1990). Effects of oil on marine mammals were not well studied at most 
spills because of lack of baseline data and/or the brevity of the post-
spill surveys. The largest documented impact of a spill, prior to EVOS, 
was on young seals in January in the Gulf of St. Lawrence (St. Aubin, 
1990). Brownell and Le Boeuf (1971) found no marked effects of oil from 
the Santa Barbara oil spill on California sea lions or on the mortality 
rates of newborn pups.
    Intensive and long-term studies were conducted after the EVOS in 
Alaska. There may have been a long-term decline of 36% in numbers of 
molting harbor seals at oiled haul-out sites in Prince William Sound 
following EVOS (Frost et al., 1994a). However, in a reanalysis of those 
data and additional years of surveys, along with an examination of 
assumptions and biases associated with the original data, Hoover-Miller 
et al. (2001) concluded that the EVOS effect had been overestimated. 
The decline in attendance at some oiled sites was more likely a 
continuation of the general decline in harbor seal abundance in Prince 
William Sound documented since 1984 (Frost et al., 1999) rather than a 
result of EVOS. The results from Hoover-Miller et al. (2001) indicate 
that the effects of EVOS were largely indistinguishable from natural 
decline by 1992. However, while Frost et al. (2004) concluded that 
there was no evidence that seals were displaced from oiled sites, they 
did find that aerial counts indicated 26% fewer pups were produced at 
oiled locations in 1989 than would have been expected without the oil 
spill. Harbor seal pup mortality at oiled beaches was 23% to 26%, which 
may have been higher than natural mortality, although no baseline data 
for pup mortality existed prior to EVOS (Frost et al., 1994a). There 
was no conclusive evidence of spill effects on Steller sea lions 
(Calkins et al., 1994). Oil did not persist on sea lions themselves (as 
it did on harbor seals), nor did it persist on sea lion haul-out sites 
and rookeries (Calkins et al., 1994). Sea lion rookeries and haul out 
sites, unlike those used by harbor seals, have steep sides and are 
subject to high wave energy (Calkins et al., 1994).
    Adult seals rely on a layer of blubber for insulation, and oiling 
of the external surface does not appear to have adverse 
thermoregulatory effects (Kooyman et al., 1976, 1977; St. Aubin, 1990). 
Contact with oil on the external surfaces can potentially cause 
increased stress and irritation of the eyes of ringed seals (Geraci and 
Smith, 1976; St. Aubin, 1990). These effects seemed to be temporary and 
reversible, but continued exposure of eyes to oil could cause permanent 
damage (St. Aubin, 1990). Corneal ulcers and abrasions, conjunctivitis, 
and swollen nictitating

[[Page 54413]]

membranes were observed in captive ringed seals placed in crude oil-
covered water (Geraci and Smith, 1976) and in seals in the Antarctic 
after an oil spill (Lillie, 1954).
    Marine mammals can ingest oil if their food is contaminated. Oil 
can also be absorbed through the respiratory tract (Geraci and Smith, 
1976; Engelhardt et al., 1977). Some of the ingested oil is voided in 
vomit or feces but some is absorbed and could cause toxic effects 
(Engelhardt, 1981). When returned to clean water, contaminated animals 
can depurate this internal oil (Engelhardt, 1978, 1982, 1985). In 
addition, seals exposed to an oil spill are unlikely to ingest enough 
oil to cause serious internal damage (Geraci and St. Aubin, 1980, 
1982).
    Although seals may have the capability to detect and avoid oil, 
they apparently do so only to a limited extent (St. Aubin, 1990). Seals 
may abandon the area of an oil spill because of human disturbance 
associated with cleanup efforts, but they are most likely to remain in 
the area of the spill. One notable behavioral reaction to oiling is 
that oiled seals are reluctant to enter the water, even when intense 
cleanup activities are conducted nearby (St. Aubin, 1990; Frost et al., 
1994b, 2004).
    Seals that are under natural stress, such as lack of food or a 
heavy infestation by parasites, could potentially die because of the 
additional stress of oiling (Geraci and Smith, 1976; St. Aubin, 1990; 
Spraker et al., 1994). Female seals that are nursing young would be 
under natural stress, as would molting seals. In both cases, the seals 
would have reduced food stores and may be less resistant to effects of 
oil than seals that are not under some type of natural stress. Seals 
that are not under natural stress (e.g., fasting, molting) would be 
more likely to survive oiling. In general, seals do not exhibit large 
behavioral or physiological reactions to limited surface oiling or 
incidental exposure to contaminated food or vapors (St. Aubin, 1990; 
Williams et al., 1994). Effects could be severe if seals surface in 
heavy oil slicks in leads or if oil accumulates near haul-out sites 
(St. Aubin, 1990).

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 
exploratory drilling program (i.e. 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 (should 
one occur). This section describes the potential impacts to marine 
mammal habitat from the specified activity, including impacts on fish 
and invertebrates 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 well is 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 well 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 spud cans (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 54414]]

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 [mu]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 [mu]Pa. They noted:
     Startle responses at received levels of 200-205 dB re 1 
[mu]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 [mu]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 54415]]

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 Endeavour 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 Endeavour 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 not 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 54416]]

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 Endeavour jack-up rig are 160 ft 
by 35 ft (48.8 m by 10.7 m), and the dimensions for the Spartan 151 
jack-up rig are nearly the same. 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

    Lower trophic organisms and fish species are primary food sources 
for marine mammals likely to be found in the proposed project vicinity. 
Any diminishment of feeding habitat during the summer months due to an 
oil spill or response could affect the energy balance of marine 
mammals. If oil found its way into upper Cook Inlet in the area of the 
Susitna and Little Susitna rivers during the summer months, a large 
portion of Cook Inlet beluga whale Area 1 critical habitat could be 
impacted. If an oil spill were to occur later in the season, it could 
become trapped in or under the ice or travel with the thinner ice pans.
    Due to their wide distribution, large numbers, and rapid rate of 
regeneration, the recovery of marine invertebrate populations is 
expected to occur soon after the surface oil passes. Spill response 
activities are not likely to disturb the prey items of whales or seals 
sufficiently to cause more than minor effects. Spill response 
activities could cause marine mammals to avoid the disturbed habitat 
that is being cleaned. However, by causing avoidance, animals would 
avoid impacts from the oil itself. Additionally, the likelihood of an 
oil spill is expected to be very low, as discussed earlier in this 
document.
    Based on the preceding discussion of potential types of impacts to 
marine mammal habitat, and taking into account the very low likelihood 
of 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 or on 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 
prevent through mitigation (such as shutdowns). However, because take 
of beluga whales and Steller sea lions is not authorized, shutdown 
procedures will be undertaken to avoid all take of these species, 
including take by Level B harassment. For continuous sounds, such as 
those produced by drilling operations and rig tow, NMFS uses a received 
level of 120-dB (rms) to indicate 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 conductor pipe driving, 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 1 in this 
document outlines the various applicable radii for which different 
mitigation measures would apply.

                Table 1--Applicable Mitigation and Shutdown Radii for Bluecrest's Proposed Lower Cook Inlet Exploratory Drilling Program
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             190 dB radius                180 dB radius                160 dB radius                120 dB radius
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact hammer during conductor pipe   60 m (200 ft)..............  250 m (820 ft).............  1.6 km (1 mi)..............  NA.
 driving.
Airguns during VSP..................  120 m (394 ft).............  240 m (787 ft).............  2.5 km (1.55 mi)...........  NA.
Rig tow.............................  NA.........................  NA.........................  NA.........................  600 m (2,000 ft).
Deep well pumps on the jack-up rig..  NA.........................  NA.........................  NA.........................  260 m (853 ft).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rig tow source levels do not exceed 171 dB (rms); Jack-up rig source levels without deep well pumps is below ambient sound levels; NA=Not applicable

Mitigation Measures Proposed by Bluecrest

    For the proposed mitigation measures, Bluecrest listed the 
following protocols to be implemented during its exploratory drilling 
program in Cook Inlet.
1. Conductor Pipe Driving Measures
    Protected species observers (PSOs) 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). If marine mammal species for which take 
is not authorized enter this zone, then use of the impact hammer will 
cease. If cetaceans for which take is authorized enter within the 180 
dB (rms) radius of 250 m (820 ft) or if pinnipeds for which take is 
authorized enter within the 190 dB (rms) radius of 60 m (200 ft), then 
use

[[Page 54417]]

of the impact hammer will 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.
    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 and no marine mammals are observed in the applicable zones 
during that time. Monitoring will occur during all hammering sessions.
2. VSP Airgun Measures
    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). If 
marine mammal species for which take is not authorized enter this zone, 
then use of the airguns will cease. If cetaceans for which take is 
authorized enter within the 180 dB (rms) radius of 240 m (787 ft) or if 
pinnipeds for which take is authorized 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.
    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. Rig Tow and Drill Rig Operation
    As mentioned previously, these activities do not generate sounds 
that result in injury. However, PSOs will be stationed on the 
helicopter platform (bow) of the drill rig (positioned about 100 ft 
above the waterline) to watch for marine mammals. With the exception of 
the operation of the deep-well pump on the jack-up rig, the other 
machinery generates sound levels below ambient. PSOs will observe from 
the drill rig during this portion of the proposed program out to the 
120 dB radius of 260 m (853 ft). If marine mammal species for which 
take is not authorized enter this zone, then the deep well pumps will 
be turned off. The PSOs will operate from multiple stations on the rig, 
recognizing that the shutdown radius begins from the submersed pump 
housed inside the forward jack-up leg.
4. 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 must be approved before operations can 
commence.
5. 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

    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.
    NMFS proposes that 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 effecting 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,

[[Page 54418]]

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 considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means of 
effecting 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 exploratory drilling program as part 
of the IHA application. That information can be found in Appendix 2 of 
the 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 rig tow, exploratory drilling operations, 
conductor pipe driving, and VSP operations. Standard marine mammal 
observing field equipment will be used, including reticule binoculars, 
Big-eye binoculars, inclinometers, and range-finders. If conductor pipe 
driving or VSP operations occur at night, PSOs will be equipped with 
night scopes. 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 Endeavour and all other sound generating activities 
planned at the Cosmopolitan well site by Illingworth and Rodkin (2014). 
Hydroacoustical testing of the Spartan 151 was also conducted by MAI 
(2011). No SSV measurements are planned at this time for the 2015 
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.

[[Page 54419]]

     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:
     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

[[Page 54420]]

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 two; 7-8 
knots of supply barges).
    Bluecrest requests authorization to take six marine mammal species 
by Level B harassment. These six marine mammal species are: Gray whale; 
minke whale; killer whale; harbor porpoise; Dall's porpoise; and harbor 
seal. Take of Cook Inlet beluga whales is not requested, expected, or 
proposed to be authorized. 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, 
beluga whale critical habitat, or Steller sea lions. Since the sale of 
the Cosmopolitan leases from Buccaneer to Bluecrest and the slight 
change in the program (e.g., drilling of one well instead of two), NMFS 
is currently reviewing a revised biological assessment to determine 
whether take of listed marine mammals is anticipated. Mitigation 
measures requiring shutdowns of activities before belugas and Steller 
sea lions enter the Level B harassment zones will be required in any 
issued IHA.
    As noted previously in this document, for continuous sounds, such 
as those produced by drilling operations and rig tow, NMFS uses a 
received level of 120-dB (rms) to indicate 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 conductor pipe 
driving, 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 2 outlines the current acoustic criteria.

        Table 2--Current Acoustic Exposure Criteria Used by NMFS
------------------------------------------------------------------------
                                       Criterion
            Criterion                 definition           Threshold
------------------------------------------------------------------------
Level A Harassment (Injury).....  Permanent           180 dB re 1
                                   Threshold Shift     microPa-m
                                   (PTS) (Any level    (cetaceans)/190
                                   above that which    dB re 1 microPa-m
                                   is known to cause   (pinnipeds) root
                                   TTS).               mean square
                                                       (rms).
Level B Harassment..............  Behavioral          160 dB re 1
                                   Disruption (for     microPa-m (rms).
                                   impulse noises).
Level B Harassment..............  Behavioral          120 dB re 1
                                   Disruption (for     microPa-m (rms).
                                   continuous,
                                   noise).
------------------------------------------------------------------------

    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 for harbor 
porpoise and harbor seal were calculated by multiplying summer density 
for the species (which constitutes the best available density 
information) by the area of ensonification for each type of activity by 
the total number of days that each activity would occur. For the other 
four species (minke, gray, and killer whales and Dall's porpoise), 
there are no available density estimates because of their low 
occurrence rates in Cook Inlet. Therefore, take requests for those 
species are based on opportunistic sightings data and typical group 
size for each species. Moreover, 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. Therefore, the proposed 
take estimates presented later in this document do not match those in 
Bluecrest's application. Additional detail is provided next.

Ensonified Areas

1. Rig Tow
    The jack-up rig will be towed two times during 2015. The rig will 
be wet-towed by at least two ocean-going tugs licensed to operate in 
Cook Inlet. 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 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 less than the dominant hearing frequencies for pinnipeds 
and toothed whales. Because it is currently unknown which tug or tugs 
will be used to tow the rig, and there are few sound signatures for 
tugs in general, the potential area that could be ensonified by 
disturbance-level noise is calculated based on an assumed 171 dB re 1 
[mu]Pa-m source. Using Collins et al.'s (2007) 171--18.4 Log(R)--
0.00188 spreading model determine from hydroacoustic surveys in Cook 
Inlet, the distance to the 120 dB isopleth would be at 1,715 ft (523 
m). The associated ZOI (area ensonified by noise greater than 120 dB) 
is, therefore, 212 acres (0.86 km\2\).
2. Conductor Pipe Driving
    The Delmar D62-22 diesel impact hammer proposed to be used by 
Bluecrest to drive the 30-inch conductor 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 3.1 mi\2\ (8.3 km\2\).
3. Deep-well Pumps (Jack-up rig)
    Bluecrest proposes to use the jack-up drilling rig Endeavour for 
the Cook Inlet program. Because the drilling platform and other noise-
generating equipment on a jack-up rig are located above the sea's 
surface, and there is very little surface contact with the water 
compared to drill ships and semisubmersible drill rigs, lattice-legged 
jack-up drill rigs are relatively quiet (Richardson et al., 1995a; 
Spence et al., 2007).
    The Spartan 151, the only other jack-up drill rig currently 
operating in the Cook Inlet, was hydroacoustically measured by Marine 
Acoustics, Inc. (2011) in 2011. This jack-up rig would be used by 
Bluecrest if the Endeavour is not available. The survey results showed 
that continuous noise levels exceeding 120 dB re 1 [mu]Pa extended out 
only 50 m (164 ft), and that this noise was largely associated with the 
diesel engines used as hotel power generators, rather than the drilling 
table. Similar, or lesser, noise levels were expected to be

[[Page 54421]]

generated by the Endeavour because generators are mounted on pedestals 
specifically to reduce noise transfer through the infrastructure, and 
enclosed in an insulated engine room, with the intent of reducing 
underwater noise transmission to levels even lower than the Spartan 
151. This was confirmed during an SSV test on the Endeavour by 
Illingworth and Rodkin (2014) in May 2013 where it was determined that 
the noise levels associated with drilling and operating generators are 
below ambient.
    However, the SSV identified another sound source, the submersed 
deep-well pumps, which were emitting underwater noise exceeding 120 dB. 
In the initial testing (Illingworth and Rodkin, 2014), the noise from 
the pump and the associated falling (from deck level) water discharge 
was found to exceed 120 dB re 1 [mu]Pa at a distance just beyond 984 ft 
(300 m). After the falling water was piped as a mitigation measure to 
reduce noise levels, the pump noise was retested (Illingworth and 
Rodkin, 2014) with the results indicating that the primary deep-well 
pump, operating inside the bow leg, still exceeded 120 dB re 1 [mu]Pa 
at a maximum of 853 ft (260 m). For calculating potential incidental 
harassment take, the 853-ft (260-m) distance to the 120 dB isopleth 
will be used giving a ZOI of 52.5 acres (0.21 km\2\).
4. 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 7.4 mi\2\ (19.2 km\2\).

Marine Mammal Densities

    Density estimates were derived for harbor porpoises and harbor 
seals as described next. Because of their low numbers, there are no 
available Cook Inlet density estimates for the other marine mammals 
that occasionally inhabit Cook Inlet near Anchor Point.
1. Harbor Porpoise
    Hobbs and Waite (2010) calculated a Cook Inlet harbor porpoise 
density estimate of 0.013 per km\2\ based on sightings recorded during 
a summer 1998 aerial survey targeting beluga whales. They derived the 
value by dividing estimated number of harbor porpoise inhabiting Cook 
Inlet (249) by the area of the entire inlet (18,948 km\2\).
2. Harbor Seal
    Boveng et al. (2003) estimated the harbor seal population that 
inhabits Cook Inlet at 5,268 seals based on summer/early fall surveys. 
Dividing that value by the area of the inlet (18,948 km\2\) provides a 
Cook Inlet-wide density of 0.278 seals per km\2\. It is presumed that 
harbor seal densities in lower Cook Inlet will remain the same 
throughout the open water season (until about November when winter ice 
conditions begin moving animals out of upper Cook Inlet).

Proposed Take Estimates

    As noted previously in this document, the potential number of 
harbor porpoises and harbor seals that might be exposed to received 
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 by the 120 dB re 1 
[mu]Pa (rms) SPL (rig tow and deep-well pumps) and 160 dB re 1 [mu]Pa 
(rms) SPL (VSP airgun operations and impact hammering); 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 total duration for rig tow over the entire season 
would be 2 days.
     It is estimated to take up to 90 days to drill one well, 
including 15 days of well testing.
     The maximum total duration of impact hammering during 
conductor 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 3 outlines the total number 
of Level B harassment exposures for harbor seals and harbor porpoises 
from each of the four activities using the calculation and assumptions 
described here.

  Table 3--Potential Number of Exposures to Level B Harassment Thresholds During Bluecrest's Proposed Exploratory Drilling Program During the 2015 Open
                                                                      Water Season
--------------------------------------------------------------------------------------------------------------------------------------------------------
                            Species                                  Rig tow       Deep-well pump     Pipe driving           VSP              Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor porpoise...............................................              0.02               1.8               0.3               0.5                 3
Harbor Seal...................................................               0.5               5.4               6.9              10.7                24
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In the IHA application, Bluecrest notes that these estimates may be 
low based on 2013 marine mammal monitoring data. Data collected during 
marine mammal monitoring at Cosmopolitan State A-1 during 
summer 2013 recorded 104 harbor porpoise, 72 harbor seals, 32 minke 
whales, 19 Dall's porpoise, 12 gray whales, and two killer whales 
between May and August (112 days of monitoring). Of those sightings, 12 
harbor porpoises and 18 harbor seals were sighted within the applicable 
Level B isopleths. Three minke whales were recorded within 984 ft (300 
m) of the active drill rig. None of the gray whales, Dall's porpoises, 
or killer whales were seen within the Level B isopleths.
    For the less common marine mammals such as gray, minke, and killer 
whales and Dall's porpoises, population estimates within lower Cook 
Inlet are too small to calculate 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 group size, the 
potential for attraction, and the 2013 marine mammal sighting data 
(with buffers added in to account for missed sightings).
    Table 4 here outlines density estimates (where available), NMFS' 
proposed Level B harassment take levels, the abundance of each species 
in Cook Inlet, the percentage of each species or stock estimated to be 
taken, and current population trends.

[[Page 54422]]



 Table 4--Density Estimates, Proposed Level B Harassment Take Levels, Species or Stock Abundance, Percentage of
                            Population Proposed To Be Taken, and Species Trend Status
----------------------------------------------------------------------------------------------------------------
                                   Density
           Species               (/   Proposed level      Abundance      Percentage of       Trend
                                   km\2\)          B take                          population
----------------------------------------------------------------------------------------------------------------
Harbor Seal..................           0.278             100  22,900..........             0.4  Stable
Harbor Porpoise..............           0.013             150  25,987..........             0.6  No reliable
                                                                                                  information.
Killer Whale.................              NA               5  1,123 (resident)            0.45  Resident stock
                                                                                                  possibly
                                                                                                  increasing.
                               ..............  ..............  552 (transient).            0.91  Transient stock
                                                                                                  stable.
Gray whale...................              NA              20  18,017..........             0.1  Stable/
                                                                                                  increasing.
Minke whale..................              NA              50  810-1,233.......         4.1-6.2  No reliable
                                                                                                  information.
Dall's porpoise..............              NA              40  83,400..........            0.05  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.
    No injuries or mortalities are anticipated to occur as a result of 
Bluecrest's proposed exploratory 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 
extremely remote. 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.
    None of the species for which take is proposed to be authorized are 
listed as threatened or endangered under the ESA nor as depleted under 
the MMPA. 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. The continuous sounds produced by the drill rig do not even 
rise to the level thought to cause auditory injury 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 either. 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 exploratory 
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, drilling operations will not occur 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

[[Page 54423]]

of the proposed monitoring and mitigation measures, NMFS preliminarily 
finds that the total marine mammal take from Bluecrest's proposed 
exploratory 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 represent 0.45 
percent of the Alaska resident stock and 0.91 percent of the Gulf of 
Alaska, Aleutian Island and Bering Sea stock of killer whales (1,123 
residents and 552 transients), 0.6 percent of the Gulf of Alaska stock 
of approximately 25,987 harbor porpoises, 0.5 percent of the Alaska 
stock of approximately 83,400 Dall's porpoises, 4.1-6.2 percent of the 
Alaska stock of approximately 810-1,233 minke whales, and 0.1 percent 
of the eastern North Pacific stock of approximately 18,017 gray whales. 
The take request presented for harbor seals represent 0.4 percent of 
the Cook Inlet/Shelikof stock of approximately 29,175 animals. These 
take 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 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 the 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 period (2008-2012), if the average 
abundance for the Cook Inlet beluga whales from the prior five years 
(2003-2007) is below 350 whales. The next 5-year period that could 
allow for a harvest (2013-2017), would require the previous five-year 
average (2008-2012) to be above 350 whales. The 2008 Cook Inlet Beluga 
Whale Subsistence Harvest Final Supplemental Environmental Impact 
Statement (NMFS, 2008a) authorizes how many beluga whales can be taken 
during a 5-year interval based on the 5-year population estimates and 
10-year measure of the population growth rate. Based on the 2008-2012 
5-year abundance estimates, 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 2014. Residents in the villages of 
Homer, Ninilchik, and Kenai are the primary subsistence users near the 
Cosmopolitan drill site.
    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 exploratory drilling operation. Marine mammals 
could be behaviorally harassed and either become more difficult to hunt 
or temporarily abandon

[[Page 54424]]

traditional hunting grounds. If a large or very large oil spill 
occurred, it could impact subsistence species. However, as previously 
mentioned one is not anticipated to occur, 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 exploratory 
drilling program should not have any impacts to beluga harvests as none 
currently occur in Cook Inlet, and no takes of belugas are anticipated 
or proposed to be authorized. Additionally, subsistence harvests of 
other marine mammal species are limited in Cook Inlet and typically 
occur in months when the proposed exploratory drilling program would 
not operate.

Plan of Cooperation or Measures To Minimize Impacts to Subsistence 
Hunts

    Regulations at 50 CFR 216.104(a)(12) require IHA applicants for 
activities that take place in Arctic waters to provide a Plan of 
Cooperation or information that identifies what measures have been 
taken and/or will be taken to minimize adverse effects on the 
availability of marine mammals for subsistence purposes. NMFS 
regulations define Arctic waters as waters above 60[deg] N. latitude. 
Bluecrest's Cosmopolitan State B-1 well location is south of 
60[deg] N. latitude; therefore, a Plan of Cooperation is not required 
for this proposed project. However, 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 2014 or 2015. 
Moreover, no take of belugas is anticipated or proposed to be 
authorized. 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 is 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 
exploratory 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 unmitgable adverse impact on marine mammal availability for 
subsistence uses from take incidental to 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 (of two wells) in lower Cook Inlet is not 
likely to adversely affect beluga whales, beluga whale critical 
habitat, or Steller sea lions. The original proposed action that was 
the subject of the section 7 consultation involved two wells to be 
drilled at the Cosmopolitan location by Buccaneer, not Bluecrest. The 
U.S. Army Corps of Engineers has requested a reinitiation of 
consultation and submitted a revised biological assessment to NMFS. 
That informal consultation will be concluded prior to a final 
determination on this MMPA IHA request. Mitigation measures laid out in 
the April 25, 2013, section 7 Letter of Concurrence to ensure no take 
of beluga whales and Steller sea lions have been proposed for inclusion 
in any issued IHA. Any new measures that arise from the reinitiated 
consultation would also be included in any issued IHA. Therefore, NMFS' 
Office of Protected Resources does not intend to initiate formal 
consultation under Section 7 of the ESA.

National Environmental Policy Act (NEPA)

    NMFS has prepared a Draft Environmental Assessment (EA) for 
issuance of an IHA to Bluecrest for the proposed exploratory drilling 
program in lower Cook Inlet. The Draft EA has been made available for 
public comment concurrently with this proposed IHA (see ADDRESSES). 
NMFS will either finalize the EA and prepare a FONSI or prepare an 
Environmental Impact Statement 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 exploratory drilling 
program in lower Cook Inlet during the 2015 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 April 1, 2015, through March 31, 2016.
    2. This IHA is valid only for activities associated with 
Bluecrest's lower Cook Inlet exploratory drilling program. The specific 
areas where Bluecrest's exploratory drilling operations will occur are 
described in the July 2014 IHA application and depicted in Figure 1 of 
the application.
    3. Species Authorized and Level of Take
    a. The incidental taking of marine mammals, by Level B harassment 
only, is limited to the following species in the waters of Cook Inlet:

[[Page 54425]]

    i. Odontocetes: 150 harbor porpoise; 40 Dall's porpoise; and 5 
killer whales.
    ii. Mysticetes: 20 gray whales and 50 minke whales.
    iii. Pinnipeds: 100 harbor seals.
    iv. If any marine mammal species not listed in conditions 3(a)(i) 
through (iii) are encountered during exploratory drilling 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.
    b. The taking by injury (Level A harassment), serious injury, or 
death of any of the species listed in condition 3(a) or the taking of 
any kind of any other species of marine mammal is prohibited and may 
result in the modification, suspension, or revocation of this IHA.
    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\;
    b. continuous drill rig sounds during active drilling operations 
and from rig tow; and
    c. impact hammer during conductor 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, 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 a sufficient number of NMFS-qualified, vessel-based 
Protected Species Observers (PSOs) to visually watch for and monitor 
marine mammals near the drill rig during daytime operations (from 
nautical twilight-dawn to nautical twilight-dusk) and before and during 
start-ups of sound sources day or night. 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, 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, speed if under tow, 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. Conductor Pipe Driving 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 are about to enter this zone, then use 
of the impact hammer will cease.
    ii. If cetaceans for which take is authorized approach or enter 
within the 180 dB (rms) radius of 250 m (820 ft) or if pinnipeds for 
which take is authorized approach or enter within the 190 dB (rms) 
radius of 60 m (200 ft), then use of the impact hammer will 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 are about to enter this zone, then use 
of the airguns will cease.
    ii. If cetaceans for which take is authorized approach or enter 
within the 180 dB (rms) radius of 240 m (787 ft) or if pinnipeds for 
which take is authorized 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 30 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

[[Page 54426]]

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 (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);
    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 drilling operation activities;
    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);
    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.
    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 seismic 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.
    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).

[[Page 54427]]

    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 exploratory 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: September 5, 2014.
Perry F. Gayaldo,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2014-21662 Filed 9-10-14; 8:45 am]
BILLING CODE 3510-22-P