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Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Construction and Operation of Offshore Oil and Gas Facilities in the Beaufort Sea, Alaska

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


Notice of issuance of a letter of authorization.


In accordance with the Marine Mammal Protection Act (MMPA), as amended, and implementing regulations, notice is hereby given that NMFS has issued a letter of authorization (LOA) to BP Exploration (Alaska), Inc. (BP) to take marine mammals incidental to the production of offshore oil and gas at the Northstar development in the Beaufort Sea off Alaska.


This Authorization is effective from July 7, 2007, through July 6, 2008.


The LOA and supporting documentation may be obtained by writing to P. Michael Payne, Office of Protected Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910, or by telephoning one of the contacts listed here.

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Candace Nachman or Kenneth R. Hollingshead (301) 713-2289, or Bradley Smith (907) 271-3023.

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Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1361 et seq.) directs NMFS to allow, on 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 by NMFS and regulations are issued. Under the MMPA, the term “take” means to harass, hunt, capture, or kill or to attempt to harass, hunt, capture, or kill marine mammals.

Authorization, in the form of annual LOAs, may be granted for periods up to 5 years if NMFS finds, after notice and opportunity for public comment, that the taking will have a negligible impact on the species or stock(s) of marine mammals and will not have an unmitigable adverse impact on the availability of the species or stock(s) of marine mammals for subsistence uses. In addition, NMFS must prescribe regulations setting forth the permissible methods of taking and other means of effecting the least practicable adverse impact on the species and its habitat, and on the availability of the species for subsistence uses. The regulations also must include requirements pertaining to the monitoring and reporting of such taking. Regulations governing the taking of marine mammals incidental to construction and operation of the offshore oil and gas facility at Northstar were made effective on April 6, 2006 (71 FR 11314, March 7, 2006), and remain in effect until April 6, 2011. These regulations include mitigation, monitoring, and reporting requirements. The six species of marine mammals that BP may take in small numbers during construction and operation of the Northstar facility are bowhead whales (Balaena mysticetus), gray whales (Eschrichtius robustus), beluga whales (Delphinapterus leucas), ringed seals (Phoca hispida), spotted seals (Phoca largha), and bearded seals (Erignathus barbatus).

Impacts on marine mammals may occur through noise from barge, helicopter traffic, drilling, and other noise sources on the island facility. Impacts may also result if there is an oil spill resulting from production. While noise impacts on marine mammals will be low (activities on Northstar Island will make less noise than that from standard jack-up rigs, the concrete island drilling structure, or seismic activity), marine mammals will likely hear the noise at distances up to 10 km (6.2 mi) from the island. In addition, there may be some harassment (including injury or mortality) of ringed seals during winter ice-road construction. No take is authorized for an oil spill.

As oil spills are highly unlikely, impacts on marine mammals from an oil spill are also unlikely to take place. However, in order to mitigate the potential for impacts on bowheads and the subsistence use of bowheads, BP will not drill into oil-bearing strata during periods of open water or broken ice, essentially the time period between June 13 and ending with the presence of 18 inches of continuous ice cover for one-half mile in all directions. Mitigation has been proposed by BP to the North Slope Borough native community to ensure that, in the event that an oil spill does occur, it will not have an unmitigable adverse impact on the subsistence use of the bowhead whale.

Additionally, take of marine mammals will also be minimized through implementation of the following mitigation measures: (1) Start Printed Page 38066avoiding sea lairs by 100 m (328 ft) if new activities occur on the floating sea ice after March 20; (2) establishing and monitoring during all daylight hours a 190 dB safety zone for seals and a 180 dB safety zone for whales; (3) visually monitoring of the safety zones for at least 30 minutes prior to the commencement of activities; (4) shutting-down of sound sources if marine mammals enter the respective safety zones; (5) scheduling non-essential boat, barge, and air traffic to avoid periods when bowhead whales are migrating through the area; and (6) limiting helicopter flights to a corridor from Seal Island to the mainland, and, except when limited by weather, will maintain a minimum altitude of 1,000 ft (305 ft), except during takeoff and landing.

Monitoring and Reporting

Monitoring and reporting requirements are contained in the Northstar regulations (50 CFR 216.206) and described in the final rule (71 FR 11314, March 7, 2006). Monitoring reports are submitted annually as required by the regulations and the LOA and plans and reports are peer-reviewed as required by the MMPA and regulations. A list of these reports is available upon request (see ADDRESSES). No new activities were conducted during the summer of 2006, and therefore, no specific acoustic recordings of new sources were undertaken in 2006. Acoustic monitoring of the 2006 bowhead whale migration was implemented during the fall of 2006, as planned. No industrial source operating at Northstar during the past year has produced sounds capable of reaching 180 dB in the water, and therefore, no monitoring of the “safety radii” has been implemented. Ice-road and other construction activities on previously undisturbed ice were not initiated after March 1, 2006; therefore, dog-assisted surveys of such areas were not required in 2006.

Summary of Request

On April 23, 2007, NMFS received a request from BP for a renewal of an LOA issued on July 7, 2006, for the taking of marine mammals incidental to oil production operations at Northstar, under section 101(a)(5)(A) of the MMPA. This request (BP, 2007) contains information in compliance with 50 CFR 216.209, which updates information provided in BP's original application for takings incidental to construction and operations at Northstar.

Summary of Activity and Monitoring Under the Current LOA

One offshore ice road was built during the 2005-2006 ice-covered season. Helicopters made 465 round trips to Northstar during the 2005-2006 ice-covered season to transport crew and materials to and from the facility and recommended flight corridors and altitude restrictions were maintained. Hagglunds tracked vehicles made 70 round trips between West Dock and Northstar Island, and the hovercraft made 249 round trips during the 2005-2006 ice-covered season.

Drilling activities were conducted at six well sites during the reporting period. Two new wells were drilled and completed, and surface drilling was conducted at a third new well site. Routine maintenance activities to repair the block system and fabric barrier around Northstar Island occurred from May 26 through June 28, 2006.

Each month, six to seven aerial surveys were conducted to inspect the pipeline for leaks or spills. There were 17 reportable Northstar-related spills during the 2005-2006 ice-covered season. Material spilled included corrosion inhibitor, scale inhibitor, diesel fuel, hydraulic fluid, anti-foulant, drilling mud, sulfuric acid, hydrochloric acid, and sewage. Most of this material remained in contaminant and was recovered. Smaller amounts of some materials, including sewage, corrosion inhibitor, hydraulic oil, drilling mud, hydrochloric and sulfuric acid, and diesel fuel were spilled outside of containment. All material spilled during this ice-covered season was cleaned up.

During the open-water period, there were 261 helicopter round trips, 560 hovercraft round trips, 64 tug and barge trips, and 106 Alaska Clean Seas Bay-class boat round trips to Northstar. There were an additional five trips by Bay-class boats in association with acoustic monitoring of the bowhead whale migration. Three reportable spills occurred during the 2006 open-water period. Spilled material included scale and corrosion inhibitor and lube oil. All spilled material was cleaned up.

No responses of seals to Northstar activities were noted during monitoring surveys other than that a seal was noted to raise its head in 2005, possibly in response to Northstar activities. Results of seal counts conducted from Northstar Island during the reporting period did not provide evidence, or reason to suspect, that any seals were killed or injured by Northstar-related activities during 2006. No activities were conducted that could have exposed pinnipeds and whales to underwater received levels greater than 190 dB re 1 microPa (rms) or 180 dB re 1 microPa (rms), respectively. There were no spills of liquid hydrocarbons that reached the water under the sea ice.

Seven Directional Autonomous Seafloor Acoustic Recorders (DASARs) were installed from August to September, 2006. Four of the devices were deployed at locations 11.5-16.6 km (7.1-10.3 mi) NNE of Northstar Island and recorded low-frequency sounds continuously for approximately 18 days. Near-island recordings were obtained from three DASARs placed 410-465 m (1,345-1,525 ft) from Northstar over approximately 27 days. In total, 1,509 bowhead whale calls were recorded over approximately 18 days at the four offshore DASAR locations. This number is lower than calls recorded from 2001-2004 but higher than the number recorded in 2005 (Richardson, 2007). The low call counts in 2006 are probably related to the presence of heavy nearshore ice during the 2006 season, which may have deflected the migration pathway farther offshore than in years with open water (i.e., 2001-2004). The 2006 season also had the fewest days of recording offshore. A new sound was recorded in 2006 that has not been heard before. The acoustic technicians do not believe these sounds were produced by whales, but they have not discovered their origin(s) (Richardson, 2007).

Sound emissions associated with Northstar activities in 2006 were probably somewhat higher than in 2005, and this difference would mainly be attributable to extra boat traffic rather than island sounds per se. Nevertheless, sound emissions associated with Northstar activities in 2006 were below sound emissions in 2001, 2002, and 2003. The number of whales deflected offshore in response to Northstar operations in 2006 cannot be estimated by the methods that have been applied to the more extensive datasets acquired in 2001-2004. However, if the overall migration corridor in the central Alaskan Beaufort Sea was farther offshore in 2006 than in some other recent years, as various indicators suggest, then Northstar sounds would have been (on average) less audible to bowhead whales than at some times in the past. In that case, the number of whales deflected by Northstar-related sounds in 2006 would likely be toward the low end of the range for 2001-2004.

Subsistence hunters from Nuiqsut who traveled to Cross Island for the annual bowhead whale hunt did not report any negative effects from Northstar activities on their ability to Start Printed Page 38067conduct the hunt. The full quota of whales was taken.


BP complied with the requirements of the 2006 LOA, and NMFS has determined that the marine mammal take resulting from the 2006 construction and operation activities is within that analyzed in and anticipated by the associated regulations. Accordingly, NMFS has issued a 1-year LOA to BP, authorizing the taking of marine mammals incidental to oil production operations at the Northstar offshore facility in state and Federal waters in the U.S. Beaufort Sea. Issuance of this LOA is based on findings described in the preamble to the final rule (71 FR 11314, March 7, 2006) and supported by information contained in BP's 2006 annual report that the activities described in the LOA will result in the taking of no more than small numbers of bowhead whales, beluga whales, ringed seals, and, possibly California gray whales, bearded seals, and spotted seals and that the total taking will have a negligible impact on these marine mammal stocks and would not have an unmitigable adverse impact on the availability of these species or stocks for taking for subsistence uses.

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Dated: July 6, 2007.

James H. Lecky,

Director, Office of Protected Resources, National Marine Fisheries Service.

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[FR Doc. E7-13556 Filed 7-11-07; 8:45 am]