Small Takes of Marine Mammals Incidental to Specified Activities; Seismic Surveys in the Beaufort and Chukchi Seas off Alaska, 17864-17873 [E7-6753]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 72, Number 68 (Tuesday, April 10, 2007)]
[Notices]
[Pages 17864-17873]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-6753]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 010207B]


Small Takes of Marine Mammals Incidental to Specified Activities; 
Seismic Surveys in the Beaufort and Chukchi Seas off Alaska

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

ACTION:  Notice of receipt of application and proposed incidental take 
authorization; request for comments.

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SUMMARY:  NMFS has received an application from Shell Offshore, Inc. 
(SOI) for an Incidental Harassment Authorization (IHA) to take small 
numbers of marine mammals, by harassment, incidental to conducting 
open-water offshore exploratory drilling on Outer Continental Shelf 
(OCS) oil lease blocks in the Beaufort Sea off Alaska. Under the Marine 
Mammal Protection Act (MMPA), NMFS is requesting comments on its 
proposal to

[[Page 17865]]

issue an IHA to SOI to incidentally take, by Level B harassment, small 
numbers of several species of marine mammals between mid-July and 
November, 2007, incidental to conducting this drilling program.

DATES:  Comments and information must be received no later than May 10, 
2007.

ADDRESSES:  Written comments on the application should be addressed to 
P. Michael Payne, Chief, Permits, Conservation and Education Division, 
Office of Protected Resources, National Marine Fisheries Service, 1315 
East-West Highway, Silver Spring, MD 20910-3225, or by telephoning the 
contact listed here. The mailbox address for providing email comments 
is PR1.010207B @noaa.gov. Comments sent via e-mail, including all 
attachments, must not exceed a 10-megabyte file size. A copy of the 
application (containing a list of the references used in this document) 
may be obtained by writing to this address or by telephoning the 
contact listed here and are also available at: https://
www.nmfs.noaa.gov/pr/permits/incidental.htm#iha.
    Documents cited in this document, that are not available through 
standard public library access methods, may be viewed, by appointment, 
during regular business hours at this address.

FOR FURTHER INFORMATION CONTACT:  Kenneth Hollingshead, Office of 
Protected Resources, NMFS, (301) 713-2289 or Brad Smith, NMFS, Alaska 
Regional Office 907-271-3023.

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 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.
    An authorization shall be granted if NMFS finds that the taking 
will have a negligible impact on the species or stock(s) and will not 
have an unmitigable adverse impact on the availability of the species 
or stock(s) for subsistence uses and the permissible methods of taking 
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.''
    Section 101(a)(5)(D) of the MMPA established an expedited process 
by which citizens of the United States can apply for an authorization 
to incidentally take small numbers of marine mammals by 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].
    Section 101(a)(5)(D) establishes a 45-day time limit for NMFS 
review of an application followed by a 30-day public notice and comment 
period on any proposed authorizations for the incidental harassment of 
marine mammals. Within 45 days of the close of the comment period, NMFS 
must either issue or deny issuance of the authorization.

Summary of Request

Open Water Exploration Drilling

    SOI is planning to utilize two drilling units during the 2007 open 
water season in order to drill priority exploration targets on their 
U.S. Minerals Management Services (MMS) OCS leases in the U.S. Beaufort 
Sea. The highest priority exploratory targets for 2007 are located 
offshore of Pt. Thomson and Flaxman Island, on the leaseholds referred 
to as Sivulliq and Olympia, in Camden Bay. However, given the locations 
of open water conditions during 2007 and permit/authorization 
stipulations, SOI may elect to re-prioritize well locations on one, or 
more of their OCS leases (see Figure 1 in SOI's IHA application). Re-
prioritizing of drilling prospects due to ice may cause drilling to 
occur at other Beaufort Sea OCS leases held by SOI, but only those that 
have been pre-cleared to the satisfaction of MMS. It is anticipated 
that the drilling vessels will each drill up to two wells during the 
open water season of 2007.
    The drilling units proposed for SOI's 2007 OCS drilling program 
include the semi-submersible drill ship, the Kulluk, and a floating 
drill ship, the Frontier Discoverer (Discoverer). Both the Kulluk and 
Discoverer will be mobilized into the Beaufort Sea as soon as ice 
conditions permit. Each will be accompanied by up to two Arctic-class, 
foreign-flagged, ice management vessels which will also serve duty as 
anchor tenders, and other drill ship support tasks. These ice 
management vessels are: the M/V Jim Kilabuk, the M/V Vladimir Ignatjuk, 
the M/V Kapitan Dranitsyn, the M/V Fennica-Nordica,; and the M/V Tor 
Viking.
    Additional support vessels, such as the M/V Peregrine and aircraft 
will also be used during the drilling season, assisting with crew 
change support and provision re-supply. Oil spill response vessels 
(OSRV) will accompany the drill ships, at all times while drilling 
occurs through prospective hydrocarbon- bearing zones. Projected dates 
for arrivals of OSRVs on location in the Beaufort Sea will be known 
around the end of April/May 2007. An ice-class, purpose built OSRV is 
being constructed for SOI and will be deployed in the Beaufort Sea for 
this drilling program. Potential OSRV support includes the Arctic 
Endeavor barge and associated tug; and an OSR tanker that will be 
staged in proximity to both drilling units. Specifications for the 
Kulluk, Discoverer and prospective ice management vessels are included 
in SOI's IHA application.
    The Kulluk is currently moored in McKinley Bay, Yukon Territory, 
Canada. Ice management support (Ignatjuk and Fennica-Nordica) for the 
Kulluk are projected to enter the Beaufort Sea during mid-late June 
2007 traveling west to east toward McKinley Bay. The Kulluk is 
projected to be towed into the Alaskan Beaufort Sea during July 2007 by 
one of the arctic class ice management vessels, which travel through 
the Chukchi and Beaufort Seas before arriving in McKinley Bay for 
mobilization. The Discoverer is currently docked in Singapore and will 
travel to Kotzebue for re-supply before mobilizing into the Beaufort 
Sea, accompanied by ice management vessels. The Dranitsyn will provide 
ice management support for the Discoverer. Both ships are expected to 
depart Kotzebue in early July before entering the Beaufort Sea.
    These vessels will traverse the Alaskan Beaufort from west to east 
and are projected to begin the traverse before July 1, 2007. These 
vessels should free the Kulluk and ready it for mobilization to the 
Alaskan Beaufort Sea by late July or early August 2007. The Tor Viking 
is projected to enter the Beaufort Sea during mid-late June 2007 and 
arrive on location of the Sivulliq prospect in late June. The Kilabuk 
will provide support and supply to the Kulluk. Toward the

[[Page 17866]]

end of July, an additional ice management vessel (the Dranitsyn) will 
escort the Discoverer from the Bering Sea northward through the Chukchi 
and Beaufort Seas to drilling prospects where ice conditions allow safe 
operating access. At the conclusion of open water operations around the 
end of October 2007, SOI expects to demobilize both the Kulluk and the 
Discoverer before the end of November 2007. The Kulluk will be 
accompanied by two ice management vessels back to the Canadian Beaufort 
Sea (McKinley Bay), while two ice management vessels will accompany the 
Discoverer west through the Beaufort Sea and south through the Chukchi 
Sea.

Pre-Feasibility Geotechnical Borehole Drilling

    To obtain geotechnical data for pre-feasibility analyses of shallow 
sub-sea sediments, SOI plans to drill as many as eight boreholes, each 
up to 400 ft (122 m) in depth. SOI notes that these boreholes will be 
completed at depths more than one mile (1.6 km) above any of the 
prospective subsurface hydrocarbon- bearing zones in the Sivulliq 
prospect (see Figure 1 in SOI's application). Three potential 
development locations will be investigated at Sivulliq, deeper 
locations along a prospective pipeline access corridor will also be 
investigated. This operation is expected to take approximately one week 
per borehole.
    The geotechnical survey component of the program will be conducted 
by a vessel typically over 200 ft (61 m) in length, with a moon-pool 
and drilling rig approximately at mid-ships, A-frame at the stern, 
helideck above the bow/bridge and accommodations for about 40 technical 
staff and crew. A typical geotechnical coring vessel is illustrated in 
Attachment A of SOI's MMPA application.
    The geotechnical drilling is expected to begin during July 2007. 
Including weather, ice conditions and logistics/resupply it is 
anticipated that geotechnical borings may require up to 8 weeks within 
a 12-week time-frame finished by the end of October 2007. The proposed 
geotechnical locations include the Sivulliq prospect and the Pt. 
Thomson to Sivulliq prospective pipeline access corridor.

Marine Mammals

    A total of three cetacean species (bowhead, gray, and beluga 
whales), three species of pinnipeds (ringed, spotted, and bearded 
seal), and one marine carnivore (polar bear) are known to occur in or 
near the proposed drilling areas in the U.S. Beaufort Sea. Other 
extralimital species that occasionally occur in very small numbers in 
this portion of the U.S. Beaufort Sea include the harbor porpoise and 
killer whale. However, because of their rarity in this area, they are 
not expected to be exposed to, or affected by, any activities 
associated with the drilling, and are not discussed further. The polar 
bear is under the jurisdiction of the U.S. Fish and Wildlife Service 
(USFWS) and is not discussed further in this document. The species and 
numbers of marine mammals likely to be found within this portion of the 
Beaufort Sea are listed in Table 4-1 in SOI's IHA application.
    A description of the biology and distribution of the marine mammal 
species under NMFS' jurisdiction can be found in SOI's IHA application, 
MMS' 2006 PEA for Arctic seismic activities, the NMFS/MMS Draft 
Programmatic EIS for Arctic Seismic in the Beaufort and Chukchi seas 
and several other documents (e.g., MMS Final EA for Lease Sale 202, 
Army Corps of Engineers for the Northstar Project, 1999). Information 
on these species can be found also in the NMFS Stock Assessment 
Reports. The 2006 Alaska Stock Assessment Report is available at: 
https://www.nmfs.noaa.gov/pr/sars/region.htm Please refer to these 
documents for information on these potentially affected marine mammal 
species.

Potential Effects of Seismic Surveys on Marine Mammals

    Disturbance by drilling sounds is the principal means of taking by 
this activity. Drilling vessels, support vessels including ice 
management vessels, and aircraft may provide a potential second source 
of noise. The physical presence of vessels and aircraft could also lead 
to non-acoustic effects on marine mammals involving visual or other 
cues.
    As outlined in previous NMFS documents, the effects of noise on 
marine mammals are highly variable, and can be categorized as follows 
(based on Richardson et al., 1995):
    (1) The noise may be too weak to be heard at the location of the 
animal (i.e., lower than the prevailing ambient noise level, the 
hearing threshold of the animal at relevant frequencies, or both);
    (2) The noise may be audible but not strong enough to elicit any 
overt behavioral response;
    (3) The noise may elicit reactions of variable conspicuousness and 
variable relevance to the well being of the marine mammal; these can 
range from temporary alert responses to active avoidance reactions such 
as vacating an area at least until the noise event ceases;
    (4) Upon repeated exposure, a marine mammal may exhibit diminishing 
responsiveness (habituation), or disturbance effects may persist; the 
latter is most likely with sounds that are highly variable in 
characteristics, infrequent and unpredictable in occurrence, and 
associated with situations that a marine mammal perceives as a threat;
    (5) Any anthropogenic noise that is strong enough to be heard has 
the potential to reduce (mask) the ability of a marine mammal to hear 
natural sounds at similar frequencies, including calls from 
conspecifics, and underwater environmental sounds such as surf noise;
    (6) If mammals remain in an area because it is important for 
feeding, breeding or some other biologically important purpose even 
though there is chronic exposure to noise, it is possible that there 
could be noise-induced physiological stress; this might in turn have 
negative effects on the well-being or reproduction of the animals 
involved; and
    (7) Very strong sounds have the potential to cause temporary or 
permanent reduction in hearing sensitivity. In terrestrial mammals, and 
presumably marine mammals, received sound levels must far exceed the 
animal's hearing threshold for there to be any temporary threshold 
shift (TTS) in its hearing ability. For transient sounds, the sound 
level necessary to cause TTS is inversely related to the duration of 
the sound. Received sound levels must be even higher for there to be 
risk of permanent hearing impairment. In addition, intense acoustic or 
explosive events may cause trauma to tissues associated with organs 
vital for hearing, sound production, respiration and other functions. 
This trauma may include minor to severe hemorrhage.
    The only anticipated impacts to marine mammals associated with 
drilling activities are from propagation of sounds from the drilling 
units and associated support vessels and aircraft. SOI and NMFS believe 
that any impacts on the whale and seal populations of the Beaufort Sea 
activity area are likely to be short term and transitory arising from 
the temporary displacement of individuals or small groups from 
locations they may occupy at the times they are exposed to intermittent 
drilling sounds at the 120-190 db received levels. As noted in SOI's 
IHA application, it is highly unlikely that animals will be exposed to 
sounds of such intensity and duration as to physically damage their 
auditory mechanisms. In the case of bowhead

[[Page 17867]]

whales that displacement might well take the form of a deflection of 
the swim paths of migrating bowheads away from (seaward of) received 
noise levels greater than 160 db (Richardson et al., 1999). This study 
and other studies conducted to test the hypothesis of the deflection 
response of bowheads have determined that bowheads return to the swim 
paths they were following at relatively short distances after their 
exposure to the received sounds (SOI, 2006). To date, no evidence has 
been obtained that bowheads so exposed have incurred injury to their 
auditory mechanisms. Additionally, while there is no conclusive 
evidence that exposure to sounds exceeding 160 db have displaced 
bowheads from feeding activity (Richardson and Thomson, 2002), there is 
some information that intermittent sounds (e.g., oil drilling and 
vessel propulsion sounds) may cause a deflection in the migratory path 
of whales (Malme et al., 1983, 1984), but possibly not when the 
acoustic source is not in the direct migratory path (Tyack and Clark, 
1998).
    There is no evidence that seals are more than temporarily displaced 
from ensonified zones and no evidence that seals have experienced 
physical damage to their auditory mechanisms even within ensonified 
zones.

Distance Effects of Open Water Drilling on Marine Mammals

    The only type of incidental taking requested in SOI's IHA 
application is that of takes by noise harassment. The principal sources 
of project-created noise will be those resulting from the Kulluk and 
Discoverer and their support vessels, especially ice management 
vessels. Although the bulk of the activity will be centered in the area 
of drilling, potential exposures, or impacts to marine mammals also 
will occur as the drilling vessels, and ice management vessels mobilize 
through the Beaufort and Chukchi Seas.
    Noise propagation studies were performed on the Kulluk (Hall et 
al., 1994) in the Kuvlum prospect drill sites, approximately 6 mi (9.6 
km) east of SOI's Sivulliq prospect that SOI is proposing to drill 
during 2007. Acoustic recording devices were established at 10-m (33-
ft) and 20-m (65.6-ft) depths below water surface at varying distances 
from the Kulluk and decibel (dB) levels were recorded during drilling 
operations. There were large differences between sound propagation 
between the different water depths. At 10 m (33 ft) water depth, the 
120-db threshold had a 0.7-km (0.4-mi) radius around the Kulluk, and 
the 105-db threshold had an 8.5-km (5.3-mi) radius. At a depth of 20 m 
(66 ft) below water surface, the 120-db threshold had a radius of 8.5 
km (5.3 mi) and the 105-db threshold had a radius of 100 km (62.1 mi). 
There is no definitive explanation for the large differences in 
propagation at the different levels. Possible explanations include the 
presence of an acoustic layer due to melting ice during the sound 
studies and/or sound being channeled into the lower depths due to the 
seafloor topography (SOI, 2006). However, new sound propagation studies 
will be performed on the Kulluk, Discoverer, ice management, and 
support vessels once these vessels are at their locations for drilling 
in the Beaufort Sea.

Numbers of Marine Mammals Expected to Be Taken

    Using the marine mammal density estimates presented in Table 6-1 
(see IHA application), SOI provided estimates of the numbers of 
potential marine mammal sound exposures in Table 6-2. Average expected 
abundances for bowhead whales were derived from the Miller et al. 
(2002) feeding study in which total proportion of the population 
``moving through'' was estimated for the depth isopleths in which 
drilling operations are expected to occur. These estimates are based on 
the 160 dB re 1 microPa (rms) criteria for most cetaceans, because this 
range is assumed to be the sound source level at which marine mammals 
may change their behavior sufficiently to be considered ``taken by 
harassment.'' The proportion of bowhead whales that might occur within 
the area potentially ensonified by the 160 dB criterion was estimated 
from Richardson and Thomson (2002) in which average migrating 
distribution across the 0-20, 20-40, 40-200 and >200 m (65.6 ft, 131 
ft, 656 ft respectively) isopleths are estimated to be 25, 27, 37, and 
10 percent of the population respectively. As the majority of the 
operations related to the 2007 drilling program will occur within the 
20-40 m (65.6-131 ft) depth isopleth, SOI estimates that the average 
expected number of bowheads in this area would be 3,480 individuals. As 
a conservative estimate of potential bowheads present was twice that 
number, or a maximum estimate of 6,960 individual bowheads.
    Hall et al. (1994) utilized measurements from sonobuoys deployed at 
distances of 20, 27, and 34 km (65.6, 88.6, 111.5 ft) from active 
drilling operations to estimate that combined activities including 
drilling, geotechnical boring, vessel transit, and ice management 
activities may reach 160 dB at a distance of 200 m (656 ft) from the 
source. Although no single source produced measured sound in excess of 
160 dB, this 200-m (656-ft) distance was selected by SOI as a 
conservative estimate of potential sound propagation from drilling 
related sources. Although planned operating procedures will limit the 
number of sound sources that will be operating during any portion of 
the bowhead migration, the additional conservative assumption is made 
that 10 sources could simultaneously operate at a level to cumulatively 
produce 160 dB at 200 m (656 ft). Therefore, the total 160 dB 
ensonified area would be 2 km (1.2 mi), or approximately 7 percent of 
the 29-km (18-mi) wide 20-40 m (65.6-131 ft) isopleth. Seven percent of 
the bowhead whales present in the 20-40 m (65.6-131 ft) isopleth would 
be 244 animals at the average density estimate and 488 animals at the 
maximum density estimate.
    Based on the findings by Malme et al. (1983, 1984) for intermittent 
low-frequency noise exposures on a low-frequency hearing specialist 
(gray whales), NMFS requested SOI prepare an estimation of sound 
exposures to the level of 120 dB rms. Although the biological 
significance of this 120-dB sound level is subject to debate (as 
indicated by later research (Tyack and Clark, 1998), if the LF source 
was removed from the direct migratory path, gray whales ignored the 
signal), several related studies report (discussed next) that migrating 
bowhead whales react to and, possibly avoid, sound levels in excess of 
120 dB. As such, estimation of exposures to 120 dB levels is included 
in this discussion.
    SOI points out that one difficulty with NMFS' 120-dB criterion for 
intermittent noise is an inconsistency between field observations of 
migrating bowhead avoidance behavior associated with sound measurements 
and sound measurements and modeling that is independent of whale 
observations. The majority of observations (in the Beaufort Sea) upon 
which the 120-dB criterion are based are derived from aerial monitoring 
programs around both drilling and seismic sources. Closest observed 
proximity of bowhead whales to operating drilling or icebreaking 
operations vary between 3 km (1.86 mi) (Hall et al., 1994), 11 km (6.8 
mi) (LGL & Greeneridge, 1987) and 19 km (11.8 mi) (Ljungblad et 
al.,1987). SOI notes that there is some consistency, however, in 
estimation of the distance of deflection from drilling/ice management 
activities being in the range of 10-20 km (6.2-12.4 mi) from the 
source. Sound measurements acquired in the proximity of observed whales 
tend to be

[[Page 17868]]

approximately 120 dB leading to the conclusion that migrating bowheads 
tend to avoid sound levels in excess of 120 dB (Richardson et al., 
1995). Similar conclusions have been drawn from observations around 
operating seismic vessels (LGL, 2005).
    Projection of sound propagation from measurements of sound around 
drilling operations and seismic operations and modeled sound 
propagation (Hall et al., 1994) yielded estimations of the 120-dB 
isopleth well beyond the 20 km (12.4 mi) distance. For example, Hall et 
al. (1994) estimated the 120-dB isopleth for combined drilling/ice 
management operations to be in excess of 100 km (62 mi) from the 
source(s). While subsistence hunters report changes in migrating 
bowhead whale behavior at distance as far as 35 mi (56 km) from 
operating seismic vessels, extrapolation of avoidance to greater 
distances is not generally reported.
    For the purpose of estimation of relevant exposures for bowhead 
whales, a reasonably conservative distance of 30 km (18.6 mi) zone of 
potential exposure around drilling operations would produce exposures 
within the 0-20, 20-40, and 40-200 m (65.6 ft, 131 ft, 656 ft 
respectively) depth zones. As a result, it is possible that exposures 
to sound levels in excess of 120 dB could be experienced by as much as 
65 percent of the population (8,378 individuals).
    For all other species, the average expected abundance was estimated 
by multiplying the reported densities (Table 6-1 in the IHA 
application) for each species times a potential operational area of 840 
km2 (operational is the area in which primary drilling activities will 
occur, i.e. 29-km (18-mi) width of the 20-m - 40-m (65.6-ft - 131-ft) 
depth isopleth squared). Maximum expected abundances for all species 
were estimated by multiplying average expected abundance times two. 
Average and expected exposures were then calculated by multiplying the 
abundance times the expected portion of the operational area expected 
to be ensonified greater than 160 dB (i.e. 0.069).
    Ringed seals would be the most prevalent marine mammal species 
encountered at each of the two proposed drilling areas. Pinnipeds are 
not likely to react to sounds unless they are >170 dB re 1 microPa 
(rms), and Moulton and Lawson (2002) indicated that most pinnipeds 
exposed to 170 dB do not visibly react. Under this IHA, SOI has 
requested a take authorization for all pinnipeds using the maximum 
density between 170 and 179 dB instead of the 160 dB threshold. SOI's 
decision to use the lower estimated number is based on the theory that 
surveys for pinnipeds within the Beaufort Sea, and elsewhere, are based 
on on-ice counts which will overestimate the number of potential 
exposures (i.e., only a portion of the animals are in the water, and 
therefore, could be exposed). Spotted and bearded seals may be 
encountered in much small numbers than ringed seals, but also have the 
potential for some exposure.

Potential Impact of the Activity on the Species or Stock

    SOI states that the only anticipated impacts to marine mammals 
associated with drilling activities would be behavioral reactions to 
noise propagation from the drilling units and associated support 
vessels. NMFS notes however, that in addition to these sources of 
anthropogenic sounds, additional disturbance to marine mammals may 
result from aircraft overflights and the resulting visual disturbance 
by the drilling vessels themselves. SOI and NMFS believe, however, that 
the impacts would be temporary and result in only short term 
displacement of seals and whales from within ensonified zones produced 
by such noise sources. Any impacts on the whale and seal populations of 
the Beaufort Sea activity area are likely to be short term and 
transitory arising from the temporary displacement of individuals or 
small groups from locations they may occupy at the times they are 
exposed to drilling sounds at the 160-190 db (or lower) received 
levels. As noted, it is highly unlikely that animals will be exposed to 
sounds of such intensity and duration as to physically damage their 
auditory mechanisms. In the case of bowhead whales that displacement 
might well take the form of a deflection of the swim paths of migrating 
bowheads away from (seaward of) received noise levels greater than 160 
db (Richardson et al., 1999). Studies conducted to test the hypothesis 
of the deflection response of bowheads have determined that bowheads 
return to the swim paths they were following at relatively short 
distances after their exposure to the received sounds (SOI, 2006). 
There is no evidence that bowheads so exposed have incurred injury to 
their auditory mechanisms. Additionally, there is no conclusive 
evidence that exposure to sounds exceeding 160 db have displaced 
bowheads from feeding activity (Richardson and Thomson, 2002). Finally, 
there is no indication that seals are more than temporarily displaced 
from ensonified zones and no evidence that seals have experienced 
physical damage to their auditory mechanisms even within ensonified 
zones.

Potential Effects of Drilling Sounds and Related Activities on 
Subsistence Needs

    SOI notes that there could be an adverse impact on the Inupiat 
bowhead subsistence hunt if the whales were deflected seaward (further 
from shore) in the traditional hunting areas north of Pt. Thomson in 
Camden Bay. The impact would be that whaling crews would necessarily be 
forced to travel greater distances to intercept westward migrating 
whales thereby creating a safety hazard for whaling crews and/or 
limiting chances of successfully striking and landing bowheads. This 
potential impact is proposed to be mitigated by the application of 
mitigation procedures described later in this document and implemented 
by a Conflict Avoidance Agreement (CAA) between the SOI, the Alaska 
Eskimo Whaling Commission (AEWC) and the whaling captains' associations 
of Kaktovik, Nuiqsut and Barrow. SOI believes that the proposed 
mitigation measures will minimize adverse effects on whales and 
whalers. (see Mitigation later in this document). As a result, there 
should not be an unmitigable adverse impact on the availability of the 
marine mammal species, particularly bowhead whales, for subsistence 
uses.

Potential Impact On Habitat

    SOI states that the proposed drilling and related activities will 
not result in any permanent impact on habitats used by marine mammals, 
or to their prey sources. Any effects would be temporary and of short 
duration at any one location. The effects of the planned drilling 
activities are expected to be negligible. It is estimated that only a 
small portion of the animals utilizing the areas of the proposed 
activities would be temporarily displaced from that habitat. During the 
period of drilling activities (late-July or early-August through 
October 2007), most marine mammals would be dispersed throughout the 
Beaufort Sea area. The peak of the bowhead whale migration through the 
Beaufort Sea typically occurs in October, and efforts to reduce 
potential impacts during this time will be discussed with the affected 
whaling communities. Starting in late- August, bowheads may travel in 
proximity to the drilling activity and some might be displaced seaward 
by the planned activities. The numbers of cetaceans and pinnipeds 
subject to displacement are small in relation to abundance estimates 
for the affected mammal stocks.
    In addition, SOI states that feeding does not appear to be an 
important

[[Page 17869]]

activity by bowheads migrating through the eastern and central part of 
the Alaskan Beaufort Sea in most years. In the absence of important 
feeding areas, the potential diversion of a small number of bowheads is 
not expected to have any significant or long-term consequences for 
individual bowheads or their population. Bowheads, gray, or beluga 
whales are not predicted to be excluded from any significant habitat.
    The proposed activities are not expected to have any habitat-
related effects that would produce long-term affects to marine mammals 
or their habitat due to the limited extent of the acquisition areas and 
timing of the activities.

Proposed Mitigation and Monitoring Measures

    SOI has proposed implementing a marine mammal mitigation and 
monitoring program (MMMMP) that will consist of monitoring and 
mitigation during the exploratory drilling activities. In conjunction 
with monitoring during SOI's seismic and shallow-hazard surveys 
(subject to an upcoming notice and review), monitoring will provide 
information on the numbers of marine mammals potentially affected by 
these activities and permit real time mitigation to prevent injury of 
marine mammals by industrial sounds or activities. These goals will be 
accomplished by conducting vessel- , aerial-, and acoustic-monitoring 
programs to characterize the sounds produced by the drilling and to 
document the potential reactions of marine mammals in the area to those 
sounds and activities. Acoustic modeling will be used to predict the 
sound levels produced by the shallow hazards and drilling equipment in 
the U.S. Beaufort Sea. For the drilling program, acoustic measurements 
will also be made to establish zones of influence (ZOIs) around the 
activities that will be monitored by observers. Aerial monitoring and 
reconnaissance of marine mammals and recordings of ambient sound 
levels, vocalizations of marine mammals, and received levels should 
they be detectable using bottom-founded acoustic recorders along the 
Beaufort Sea coast will be used to interpret the reactions of marine 
mammals exposed to the activities. The components of SOI's monitoring 
program is briefly described next. Additional information can be found 
in SOI's application.

Underwater Acoustics Program

    Sounds produced during the drilling operation and by the shallow 
hazards equipment and other support vessels will be measured in the 
field during typical operations. These measurements will be used to 
establish disturbance radii for marine mammal groups within the project 
area. The objectives of SOI's planned work are: (1) to measure the 
distances from the various sound sources to broadband received levels 
of 170, 160, and 120 dB rms re 1 microPa (sounds are not expected to 
reach 180 dB), and (2) to measure the radiated vessel sounds vs. 
distance for the source and support vessels. The measurements will be 
made at the beginning of the specific activity (i.e., shallow hazards 
survey activity and drilling activity) and all safety and disturbance 
radii will be reported within 72 hours of completing the measurements. 
For the drilling operation, a subsequent mid-season assessment will be 
conducted to measure sound propagation from combined drilling 
operations during ``normal'' operations. For drilling activities, the 
primary radii of concern will be the 160-dB disturbance radii (although 
measurements will be made to the 180-dB isopleth). In addition to 
reporting the radii of specific regulatory concern, distances to other 
sound isopleths down to 120 dB (if measurable) will be reported in 
increments of 10 dB. The distance at which received sound levels become 
>120 dB for continuous sound (which occurs during drilling activities 
as opposed to impulsive sound which occurs during seismic activities) 
is sometimes considered to be a zone of potential disturbance for some 
cetacean species by NMFS. SOI plans to use vessel-based marine mammal 
observers (MMOs) to monitor the 160-dB disturbance radii around the 
seismic sound sources and, if necessary, to implement mitigation 
measures for the 190- and 180-dB safety radii. The MMOs will also 
monitor the 120-dB zone around the drilling ships. An aerial survey 
program will be implemented to monitor the 120-dB zone around the 
drilling activities in the Beaufort Sea in 2007. These two monitoring 
and mitigation programs are discussed next.
    SOI plans to use a qualified acoustical contractor to measure the 
sound propagation of the vessel-based drilling rigs during periods of 
drilling activity, and the drill ships and support vessels while they 
are underway at the start of the field season. Noise from ships with 
ice-breaking capabilities will be measured during periods of ice-
breaking activity. These measurements will be used to determine the 
sound levels produced by various equipment and to establish any safety 
and disturbance radii if necessary. Bottom-founded hydrophones similar 
to those used in 2006 for measurements of vessel-based seismic sound 
propagation will likely be used to determine the levels of sound 
propagation from the drill rigs and associated vessels. An initial 
sound source analysis will be supplied to NMFS and the drilling 
operators within 72 hours of completion of the measurements, if 
possible. A detailed report on the methodology and results of these 
tests will be provided to NMFS as part of the 90 day report following 
completion of the drilling program.

Acoustic Monitoring Program

    SOI plans to develop an acoustic component of the MMMMP to further 
understand, define, and document sound characteristics and propagation 
within the broader Beaufort Sea and potential deflections of bowhead 
whales from anticipated migratory pathways in response to vessel-based 
drilling activities. Of particular interest for this investigatory 
component is the east-west extent of deflection (i.e., how far east of 
a sound source do bowheads begin to deflect and how far to the west 
beyond the sound source does deflection persist). Of additional 
interest is the extent of offshore deflection that occurs. Currently, 
insufficient information is available on how vessel-based drilling 
noise similar to that proposed by SOI in the Beaufort Sea in 2007 may 
impact migrating bowhead whales.
    Determining the potential effects of drilling noise on migration 
bowhead whales will be complicated by the presence of ice-breaking and 
other support vessels that may contribute significantly to underwater 
sound levels. Miles et al. (1987) reported higher sound pressure levels 
(SPLs) from ice-breakers underway in open water than from vessel-based 
drilling activity. SPLs from dredging activity, a working tug, and an 
icebreaker pushing ice were also greater than those produced by vessel-
based drilling activity. However, sounds produced during drilling 
activity are relatively continuous while ice management vessel sounds 
are considered to be intermittent, and there is some concern that 
continuous and intermittent sounds may result in behavioral reactions 
(at least in mysticete whales) at a greater distance than impulse sound 
(i.e., seismic) of the same intensity.
    Acoustic localization methods provide a possible alternative to 
aerial surveys for addressing these questions. As compared with aerial 
surveys, acoustic methods have the advantage of providing a vastly 
larger number of whale detections, and can operate day or night, 
independent of visibility, and

[[Page 17870]]

to some degree independent of ice conditions and sea state-all of which 
prevent or impair aerial surveys. However, acoustic methods depend on 
the animals to call, and to some extent assume that calling rate is 
unaffected by exposure to industrial noise. Bowheads do call frequently 
in the fall, but there is some evidence that their calling rate may be 
reduced upon exposure to industrial sounds, complicating 
interpretation. Also, acoustic methods require development and 
deployment of instruments that are stationary (preferably mounted on 
the bottom) to record and localize the whale calls. According to SOI, 
acoustic methods would likely be more effective for studying impacts 
related to a stationary sound source, such as a drilling rig that is 
operating within a relatively localized area, than for a moving sound 
source such as that produced by a seismic source vessel.
    In addition, SOI plans to conduct a study in 2007 similar to the 
one conducted for seismic in 2006 in the Chukchi Sea to determine the 
effect of drilling noise and noise from support vessels and seismic 
activities on migrating bowhead whales. An acoustic ``net'' array was 
used during the 2006 field season in the Chukchi Sea. It was designed 
to (1) collect information on the occurrence and distribution of beluga 
whales that may be available to subsistence hunters near villages 
located on the Chukchi Sea coast, and (2) measure the ambient noise 
levels near these villages and record received levels of sounds from 
seismic survey activities should they be detectable. The basic 
components of this effort consisted of bottom-founded equipment for 
long-duration passive acoustic recording. A suite of autonomous 
seafloor recorders was deployed in a ``net'' array extending from 
nearshore to approximately 50 miles offshore. During the 2007 drilling 
program, SOI proposes to deploy bottom-founded acoustic recorders 
around SOI's drilling activities that have the ability of recording 
calling whales. Figure 1 in SOI's IHA application shows potential 
locations of the bottom-founded recorders and an array layout in 
relation to the drilling site. The actual locations of the bottom-
founded recorders will depend on specifications of recording equipment 
chosen for the project, and on the acoustical characteristics of the 
environment, which are yet to be determined. The results of these data 
will be used to determine the extent of deflection of migrating bowhead 
whales from the sound sources produced by the vessel-based drill rig.

Aerial Survey Monitoring Program

    SOI proposes to conduct an aerial survey program in support of its 
dual seismic exploration and drilling programs in the Beaufort Sea 
during summer and fall of 2007. The objectives of the aerial survey 
will be to: (1) advise operating vessels as to the presence of marine 
mammals in the general area of operations; (2) monitor the area east of 
the seismic activity to ensure that large numbers of bowhead mothers 
and calves do not enter the area where they would be ensonified by 
seismic sounds [gteqt]120 dB re 1microPa, which might displace them 
from feeding areas or their preferred migratory routes, (3) collect and 
report data on the distribution, numbers, movement and behavior of 
marine mammals near the seismic and drilling operations with special 
emphasis on migrating bowhead whales; (4) support regulatory reporting 
and Inupiat communications related to the estimation of impacts of 
seismic and drilling operations on marine mammals; (5) monitor the 
accessibility of bowhead whales to Inupiat hunters; and, (6) document 
how far west of seismic and drilling activities bowhead whales travel 
before they return to their normal migration paths, and if possible, to 
document how far east of seismic and drilling operations the deflection 
begins.
    For additional information on SOI's aerial survey design and other 
information, please refer to SOI's IHA application.

Vessel-based Marine Mammal Monitoring Program

    The vessel-based operations will be the core of SOI's MMMMP. The 
MMMMP will be designed to ensure that disturbance to marine mammals and 
subsistence hunts is minimized, that effects on marine mammals are 
documented, and to collect baseline data on the occurrence and 
distribution of marine mammals in the study area. Those objectives will 
be achieved, in part, through the vessel-based monitoring and 
mitigation program.
    The MMMMP will be implemented by a team of experienced MMOs, 
including both biologists and Inupiat personnel, approved in advance by 
NMFS. The MMOs will be stationed aboard the drilling vessels and 
associated support vessels throughout the drilling period. The duties 
of the MMOs will include watching for and identifying marine mammals; 
recording their numbers, distances, and reactions to the drilling 
operations; initiating mitigation measures when appropriate; and 
reporting the results. Reporting of the results of the vessel-based 
monitoring program will include the estimation of the number of 
``takes.''
    Drilling activities are expected to occur during August and October 
2007. The dates and operating areas will depend upon ice and weather 
conditions, along with SOI's arrangements with agencies and 
stakeholders. Vessel-based monitoring for marine mammals will be 
performed throughout the period of drilling operations. The vessel-
based work will provide: (1) the basis for real-time mitigation, (2) 
information needed to estimate the ``take'' of marine mammals by 
harassment, which must be reported to NMFS and USFWS, (3) data on the 
occurrence, distribution, and activities of marine mammals in the areas 
where the drilling program is conducted, (4) information to compare the 
distances, distributions, behavior, and movements of marine mammals 
relative to the source vessels at times with and without drilling or 
ice-management activity, (5) a communication channel to Inupiat whalers 
and the Whaling Coordination Center, and (6) employment and capacity 
building for local residents, with one objective being to develop a 
larger pool of experienced Inupiat MMOs.
    All MMOs will be provided training through a program approved by 
NMFS, as described later. At least one observer on each vessel will be 
an Inupiat who will have the additional responsibility of communicating 
with the Inupiat community and (during the whaling season) directly 
with Inupiat whalers. Details of the vessel-based marine mammal 
monitoring program are described in the IHA application.

Mitigation Measures During Drilling Activities

    SOI's proposed offshore drilling program incorporates both design 
features and operational procedures for minimizing potential impacts on 
marine mammals and on subsistence hunts. The design features and 
operational procedures are described in the IHA application and are 
summarized below. Survey design features to reduce impacts include: (1) 
timing and locating some drilling support activities to avoid 
interference with the annual fall bowhead whale hunts from Kaktovik, 
Nuiqsut (Cross Island), and Barrow; (2) conducting pre-season modeling 
and early season field assessments to establish the appropriate 180 dB 
and 190 dB safety zones (if necessary), and the 160 and 120 dB behavior 
radii; and (3) vessel-based (and aerial) monitoring to implement 
appropriate mitigation (and to assess the effects of project activities 
on marine mammals).

[[Page 17871]]

    Under current NMFS guidance ``safety radii'' for marine mammals 
around acoustic sources are customarily defined as the distances within 
which received pulse levels are [gteqt]180 dB re 1 microPa (rms) for 
cetaceans and [gteqt]190 dB re 1 microPa (rms) for pinnipeds. These 
safety criteria are based on an assumption that lower received levels 
will not injure these animals or impair their hearing abilities, but 
that higher received levels might have a potential for such effects. 
Mitigation measures as discussed below would be implemented if marine 
mammals are observed within or about to enter these safety radii. 
However, Greene (1987) reported SPLs ranging from 130-136 dB (rms) at 
0.2 km (656 ft) from the Kulluk during drilling activities (drilling, 
tripping, and cleaning) in the Arctic. Higher received levels up to 148 
dB (rms) were recorded for supply vessels that were underway and for 
icebreaking activities. As a result, SOI believes that the exploratory 
drilling and the activities of the support vessels are not likely to 
produce sound levels sufficient to cause temporary hearing loss or 
permanent hearing damage to any marine mammals. Consequently, standard 
mitigation as described later in this document for seismic activities 
including shut down of any drilling activity should not be necessary 
(unless sound monitoring tests described elsewhere in this document 
indicate SPLs at or greater than 180 dB). If testing indicates SPLs 
will reach or exceed 180 dB or 190 dB, then appropriate mitigation 
measures would be implemented by SOI to avoid potential Level A 
harassment of cetaceans (at or above 180 dB) or pinnipeds (at or above 
190 dB). Mitigation measures may include reducing drilling or ice 
management noises, whichever is appropriate. However, SOI plans to use 
MMOs onboard the drill ships and the various support and supply vessels 
to monitor marine mammals and their responses to industry activities. 
In addition, an acoustical program and an aerial survey program which 
are discussed in previous sections will be implemented to determine 
potential impacts of the drilling program on marine mammals.
Marine Mammal Observers
    The observer(s) (MMOs and Inupiat) will watch for marine mammals 
from the best available vantage point on the operating source vessel, 
which is usually the bridge or flying bridge. The observer(s) will scan 
systematically with the naked eye and 7 50 reticle binoculars, 
supplemented with night-vision equipment when needed (see below). 
Personnel on the bridge will assist the marine mammal observer(s) in 
watching for pinnipeds and whales. The observer(s) will give particular 
attention to the areas around the vessel. When a mammal sighting is 
made, the following information about the sighting will be recorded: 
(1) Species, group size, age/size/sex categories (if determinable), 
behavior when first sighted and after initial sighting, heading (if 
consistent), bearing and distance from seismic vessel, apparent 
reaction to seismic vessel (e.g., none, avoidance, approach, 
paralleling, etc.), closest point of approach, and behavioral pace; (2) 
time, location, heading, speed, and activity of the vessel, sea state, 
ice cover, visibility, and sun glare; (3) the positions of other 
vessel(s) in the vicinity of the source vessel. This information will 
be recorded by the MMOs at times of whale (but not seal) sightings.
    The ship's position, heading, and speed, the seismic state (e.g., 
number and size of operating airguns), and water temperature, 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. Distances to nearby marine mammals will be estimated with 
binoculars containing a reticle to measure the vertical angle of the 
line of sight to the animal relative to the horizon. Observers may use 
a laser rangefinder to test and improve their abilities for visually 
estimating distances to objects in the water. However, previous 
experience showed that this Class 1 eye-safe device was not able to 
measure distances to seals more than about 70 m (230 ft) away. However, 
it was very useful in improving the distance estimation abilities of 
the observers at distances up to about 600 m (1968 ft)-the maximum 
range at which the device could measure distances to highly reflective 
objects such as other vessels. Experience indicates that humans 
observing objects of more-or-less known size via a standard observation 
protocol, in this case from a standard height above water, quickly 
become able to estimate distances within about plus or minus 20 percent 
when given immediate feedback about actual distances during training.
    In addition to routine MMO duties, Inupiat observers will be 
encouraged to record comments about their observations into the 
``comment'' field in the database. Copies of these records will be 
available to the Inupiat observers for reference if they wish to 
prepare a statement about their observations. If prepared, this 
statement would be included in the 90-day and final reports documenting 
the monitoring work.

Mitigation for Subsistence Uses

    The Kulluk and Discoverer, and all support vessels and aircraft 
will operate in accordance with the conditions of a CAA currently being 
negotiated with the AEWC. SOI notes that the CAA for SOI's drilling 
activity will incorporate all appropriate measures and procedures 
regarding the timing and areas of the operator's planned activities 
(i.e., times and places where effects of drilling operations will be 
monitored and prospectively mitigated to avoid potential conflicts with 
active subsistence whaling and sealing); communications system between 
operator's vessels and whaling and hunting crews (i.e., the 
communications centers will be located in strategic areas); provision 
for marine mammal observers/Inupiat communicators aboard all project 
vessels; conflict resolution procedures; and provisions for rendering 
emergency assistance to subsistence hunting crews. The CAA will also 
provide guidance toward mitigating any potential adverse effects on the 
bowhead whale subsistence hunts by member of the villages of Kaktovik 
and Nuiqsut.

Reporting

    The results of the 2007 SOI vessel-based monitoring, including 
estimates of take by harassment, will be presented in the ``90 day'' 
and final technical report(s)'' usually required by NMFS under IHAs. 
SOI proposes that these technical report(s) will include: (1) summaries 
of monitoring effort: total hours, total distances, and distribution 
through study period, sea state, and other factors affecting visibility 
and detectability of marine mammals; (2) analyses of the effects of 
various factors influencing detectability of marine mammals: sea state, 
number of observers, and fog/glare; (3) species composition, 
occurrence, and distribution of marine mammal sightings including date, 
water depth, numbers, age/size/gender categories, group sizes, and ice 
cover; (4) sighting rates of marine mammals versus operational state 
(and other variables that could affect detectability); (5) initial 
sighting distances versus operational state; (6) closest point of 
approach versus seismic state; (7) observed behaviors and types of 
movements versus operational state; (8) numbers of sightings/
individuals seen versus operational state; (9) distribution around the 
drilling vessel and support vessels versus operational state; and (10) 
estimates of take based on (a) numbers

[[Page 17872]]

of marine mammals directly seen within the relevant zones of influence 
(160 dB, 180 dB, 190 dB (if SPLs of that level are measured)), and (b) 
numbers of marine mammals estimated to be there based on sighting 
density during daytime hours with acceptable sightability conditions.

Comprehensive Report

    Following the 2007 open water season, a comprehensive report 
describing the proposed acoustic, vessel-based, and aerial monitoring 
programs will be prepared. The comprehensive report will describe the 
methods, results, conclusions and limitations of each of the individual 
data sets in detail. The report will also integrate (to the extent 
possible) the studies into a broad based assessment of industry 
activities and their impacts on marine mammals in the Beaufort Sea 
during 2007. The report will form the basis for future monitoring 
efforts and will establish long term data sets to help evaluate changes 
in the Beaufort Sea ecosystem. The report will also incorporate studies 
being conducted in the Chukchi Sea and will attempt to provide a 
regional synthesis of available data on industry activity in offshore 
areas of northern Alaska that may influence marine mammal density, 
distribution and behavior.
    This comprehensive report will consider data from many different 
sources including two relatively different types of aerial surveys; 
several types of acoustic systems for data collection (net array, 
passive acoustic monitoring, vertical array, and other acoustical 
monitoring systems that might be deployed), and vessel based 
observations. Collection of comparable data across the wide array of 
programs will help with the synthesis of information. However, 
interpretation of broad patterns in data from a single year is 
inherently limited. Much of the 2007 data will be used to assess the 
efficacy of the various data collection methods and to establish 
protocols that will provide a basis for integration of the data sets 
over a period of years.

Plan of Cooperation (POC)

    SOI notes in its IHA application that POC meetings occurred in 
Barrow and Nuiqsut on October 16 and 17, 2006, and follow-up meetings 
are planned for the period May or June 2007 in these communities. SOI 
conducted a meeting with the Kaktovik Inupiat Corporation in Kaktovik 
on November 28, 2006, and will continue efforts with public and private 
organizations to hold additional meetings as needed in Kaktovik during 
2007. Following these meetings, a POC report will be prepared.
    SOI also notes in its application that negotiations were initiated 
beginning September 2006 with the AEWC to create a drilling CAA between 
SOI, and the subsistence hunting communities of Barrow, Nuiqsut, and 
Kaktovik for the 2007 drilling program activities. The drilling CAA 
will cover both the proposed Beaufort Sea exploratory and geotechnical 
drilling programs. SOI and other industry participant operators, with 
AEWC, attended public meetings and meet with the whaling captains in 
the communities of Kaktovik, Nuiqsut, and Barrow between January 29-
February 1, 2007. These meetings initiated information exchanges with 
the communities on the potential, proposed open water seismic and 
drilling programs for 2007. Additional engagements with AEWC and the 
whaling captains of Kaktovik, Nuiqsut, and Barrow will occur between 
these meetings and onset of open water activities in June/July of 2007.
    If requested, post-season meetings will also be held to assess the 
effectiveness of the 2007 drilling CAA, to address how well conflicts 
(if any) were resolved; and to receive recommendations on any changes 
(if any) might be needed in the implementation of future CAAs.

Endangered Species Act (ESA)

    NMFS has issued a biological opinion regarding the effects of oil-
and-gas activities in the Arctic Ocean on ESA-listed species and 
critical habitat under the jurisdiction of NMFS. That biological 
opinion concluded that oil-and-gas exploration activities are not 
likely to jeopardize the continued existence of listed species or 
result in the destruction or adverse modification of critical habitat. 
A copy of the Biological Opinion is available upon request (see 
ADDRESSES). NMFS will also consult on the issuance of this IHA under 
section 101(a)(5)(D) of the MMPA to SOI for this activity. Consultation 
will be concluded prior to a determination on the issuance of an IHA.

National Environmental Policy Act (NEPA)

    The information provided in the Environmental Assessment (EA) on 
the Proposed OCS Lease Sale 202 Beaufort Sea Planning Area by the MMS 
in August 2006 led MMS to determine that implementation of either the 
preferred alternative or other alternatives identified in the EA would 
not have a significant impact on the human environment. Therefore, an 
Environmental Impact Statement was not prepared by MMS. Preliminarily, 
NMFS has determined that the proposed action discussed in this document 
is not substantially different from the 2006 action. A final decision 
on whether to adopt the MMS EA as its own and issue a Finding of No 
Significant Impact, or to prepare its own NEPA document will be made by 
NMFS prior to making a final decision on the proposed issuance of an 
IHA to SOI for this activity.

Preliminary Conclusions

    Based on the information provided in SOI's application and other 
referenced documentation, NMFS has preliminarily determined that the 
impact of SOI conducting an exploratory drilling program in the U.S. 
Beaufort Sea in 2007 will have no more than a negligible impact on 
marine mammals. NMFS has preliminarily determined that the short-term 
impact of conducting exploratory drilling by two drilling vessels and 
by supporting vessels, including ice management vessels in the U.S. 
Beaufort Sea may result, at worst, in a temporary modification in 
behavior by certain species of marine mammals, including vacating the 
immediate vicinity around the activity due to noise from the activity.
    While behavioral and avoidance reactions may be made by these 
species in response to the resultant noise, this behavioral change is 
expected to have a negligible impact on the animals. While the number 
of potential incidental harassment takes will depend on the 
distribution and abundance of marine mammals (which vary annually due 
to variable ice conditions and other factors) in the area of drilling 
operations, the number of potential harassment takings is estimated to 
be small (as indicated in Table 6-2 in SOI's application). In addition, 
no take by death and/or serious injury is anticipated or would be 
authorized; there is a very low potential for an oil spill to result 
from the drilling activity, and the potential for temporary or 
permanent hearing impairment is low due to the low SPLs associated with 
drilling and ice management activities. Also, Level B harassment 
takings are likely to be avoided through the incorporation of the 
monitoring and mitigation measures mentioned in this document and 
required by the authorization. No rookeries, mating grounds, areas of 
concentrated feeding, or other areas of special significance for marine 
mammals occur within or near the planned area of operations during the 
season of operations.
    At this time NMFS is unable to make a preliminary determination 
that SOI's proposed drilling program will not have an unmitigable 
adverse impact on

[[Page 17873]]

subsistence uses of bowhead whales. As SOI notes in its IHA 
application, there could be an adverse impact on the Inupiat bowhead 
subsistence hunt if the whales were deflected seaward (further from 
shore) in the traditional hunting areas north of Pt. Thomson in Camden 
Bay. NMFS believes that this could result in whaling crews being forced 
to travel greater distances to intercept westward migrating whales 
thereby creating a significant safety hazard for whaling crews (with a 
potential loss of life), limiting chances of successfully striking and 
landing bowheads, and/or not landing bowheads quickly before 
decomposition and spoilage occurs. Prior to issuing an IHA for 
activities that take place in Arctic waters, NMFS must ensure that the 
taking by the activity will not have an unmitigable adverse impact on 
subsistence uses of marine mammals. In 50 CFR 216.103, NMFS has defined 
an ``unmitigable adverse impact'' to mean:
    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.
    While SOI states that the potential impact will be mitigated by the 
application of mitigation procedures described in its application and 
implemented by a CAA between the SOI, the AEWC and the whaling 
captains' associations of Kaktovik, Nuiqsut and Barrow, the IHA 
application does not contain suggested measures to mitigate impacts on 
the fall bowhead subsistence hunt. NMFS presumes that SOI preferred to 
not make these measures public while it continued discussions with the 
AEWC and affected whaling captains (see Plan of Cooperation). 
Mitigation measures suggested publically include warm shutdown of 
drilling operations during the subsistence hunt and moving the drilling 
structures either further offshore or behind the barrier islands. 
Therefore, while SOI believes that the mitigation measures that will be 
implemented will minimize any adverse effects on whales and whalers, 
NMFS has not been provided an opportunity to make a similar 
determination. In its application, SOI states that it would provide 
results of its discussion of measures to reduce impacts to subsistence 
uses for bowhead whales this spring. NMFS encourages SOI to complete 
its negotiations quickly to ensure NMFS being able to make the 
determinations necessary under the MMPA within the time frames provided 
by the MMPA.
    Therefore, provided the mitigation measures contained in the CAA 
are agreed upon by the involved parties (which does not include NMFS) 
and provided publically during the public comment period, NMFS proposes 
to issue an IHA to SOI for conducting an offshore drilling program in 
the U.S. Beaufort Sea in 2007, provided the previously mentioned 
monitoring and reporting requirements are incorporated. NMFS has 
preliminarily determined that the proposed activity would result in the 
harassment of small numbers of marine mammals; would have no more than 
a negligible impact on the affected marine mammal stocks; and, subject 
to development of mitigation measures during discussions with 
interested parties, would not have an unmitigable adverse impact on the 
availability of species or stocks for subsistence uses.

    Dated: April 4, 2007.
P. Michael Payne,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. E7-6753 Filed 4-9-07; 8:4