Hilcorp OK’d for Liberty hazard survey

Hilcorp Alaska has received an incidental harassment authorization from the National Oceanic and Atmosphere Administration’s National Marine Fisheries Service for a shallow geohazard survey at the site of the proposed Liberty development in the Beaufort Sea.

NMFS said July 8 that the authorization is effective July 1 through Sept. 30.

The survey will be in state and federal waters of Foggy Island Bay during the 2015 open-water season, the agency said, with the survey expected to be complete in 45 days. Hilcorp said the shallow geohazard survey and strudel scour survey would have a transition zone component on state lands, and occur in federal and state waters of Foggy Island Bay some 8 miles east of the Endicott Satellite Drilling Island, with the survey primarily within the Liberty unit.

Hilcorp said in its application that it is evaluating development of the Liberty field, in which it acquired a 50 percent interest when it bought several of BP’s smaller North Slope assets last year. The project’s preferred alternative is a gravel island to be built over the reservoir with emphasis in the survey on obtaining subsurface information for development of a subsea pipeline.

Multibeam echosounder, sidescan sonar, sub-bottom profiles and magnetometer use is planned to evaluate existence and location of archaeological resources, potential geologic hazards on the seafloor and in the shallow subsurface, and to investigate strudel scours and ice gouges. The proposed sonar survey vessel is about 40 by 14 feet in size and because of the extremely shallow project area, an additional smaller vessel may be used to safely extend vessel operations for data collection.

The incidental harassment authorization allows harassment of small numbers of marine mammals incidental to the shallow geohazard survey.

- KRISTEN NELSON