01-11579. Preparation of an Environmental Assessment for Kerr-McGee's Proposed Deepwater Development Plan Offshore Texas (Nansen Project)

AGENCY:

Minerals Management Service, Interior.

ACTION:

Preparation of an environmental assessment.

SUMMARY:

The Minerals Management Service (MMS) is preparing an environmental assessment (EA) for a proposed deepwater development plan to develop and produce hydrocarbon reserves about 117 miles offshore Texas in East Breaks, Blocks 602 and 646. This EA is being prepared in accordance with MMS's comprehensive deepwater strategy approach, which includes the preparation of comprehensive EA's, referred to as Grid EA's, in each of 17 grids in deepwater areas of the Central and Western Gulf of Mexico. This comprehensive deepwater strategy is described in detail at http:/www.gomr.mms.gov/​homepg/​regulate/​environ/​ea_​grid/​NEPADWSTRATEGY.PDF.

FOR FURTHER INFORMATION CONTACT:

Minerals Management Service, Gulf of Mexico OCS Region, 1201 Elmwood Park Boulevard, New Orleans, Louisiana 70123-2394, Mr. Ed Richardson, telephone [phone].

SUPPLEMENTAL INFORMATION:

This EA implements the tiering process outlined in 40 CFR 1502.20, which encourages agencies to tier environmental documents, eliminating repetitive discussions of the same issue. By use of reference to the most recent Final Environmental Impact Statement (EIS) for the Gulf of Mexico Western Planning Area for Lease Sales 171, 174, 177, and 180 and by tiering to related environmental documents, this EA concentrates on environmental issues specific to the proposed action.

The MMS Gulf of Mexico Region received an Initial Development Operations Coordination Document (DOCD) from Kerr-McGee Oil and Gas Corporation (Kerr-McGee) that proposes to develop and produce hydrocarbon reserves located in East Breaks, Blocks 602 and 646. The DOCD was assigned a plan control number of N-7045 and the project is referred to as the Nansen Project. Kerr-McGee will complete and produce a total of 12 wells that were drilled under previously-approved Exploration Plans for the subject blocks. No new drilling operations are proposed as a part of this DOCD. All of the wells, except the three subsea wells, will share a common surface location (a truss spar floating production system) in East Breaks, Block 602.

The Nansen truss spar is a manned floating production facility that will be permanently anchored on location by a 9-leg, taut catenary system composed of conventional wire, chain, and anchor piles. The hull portion of the spar measures approximately 90 feet in diameter and has an overall length of 543 feet. No hydrocarbons will be stored in the hull of the spar. The spar is not drilling rig capable; however, a 1,000-hp completion/workover platform rig will be installed and used for the initial completion operations. If any additional drilling would be necessary, a mobile offshore drilling unit (MODU) would be utilized. The spar will have a 20-person permanent accommodation unit installed. Temporary, portable quarters for up to 48 people may be provided.

The water depth at the truss spar location is approximately 3,675 feet. The project will use an existing onshore support base in Sabine Pass, Texas, to support the production activities. During completion or workover operations, either the onshore base in Sabine Pass, Texas, or an existing onshore base in Galveston, Texas, will be used to support these activities.

Oil and gas produced at the Nansen project will be transported off lease by third-party owned and operated right-of-way pipelines.

The proposed action analyzed in the EA will be the development plan as proposed by Kerr-McGee. Alternatives will include the proposed action with additional mitigation measures and no action (i.e., disapproval of the plan). The analyses in the EA will examine the potential environmental effects of the proposal and alternatives.

Public Comment

MMS requests interested parties to submit comments regarding issues that should be addressed in the EA to Minerals Management Service, Gulf of Mexico OCS Region, Office of Leasing and Environment, Attention: Regional Supervisor (MS 5410), 1201 Elmwood Park Boulevard, New Orleans, Louisiana 70123-2394. Comments must be submitted no later than 30 days from the publication of this Notice.

Dated: April 26, 2001.

Chris C. Oynes,

Regional Director, Gulf of Mexico OCS Region.