Published: Mar 05, 2011 2:54 AM EST
Updated: Mar 04, 2011 11:55 PM EST

ANCHORAGE, Alaska (AP) - Federal officials will study how a "very large oil spill" would affect the ocean off Alaska's northwest coast as part of a court-ordered environmental review for a 2008 offshore petroleum lease sale.

U.S. District Court Judge Ralph Beistline (BISTE'-line) of Anchorage in July ruled that the federal government had failed to follow environmental law before it sold petroleum leases in the Chukchi Sea.

The lease sale brought in nearly $2.7 billion, including $2.1 billion from a subsidiary of Shell Oil. Exploratory drilling has been held up by court challenges and a lack of permits.

Federal officials said in a court filing Friday that a draft of the spill analysis will be completed by late May, followed by a 45-day public comment period.

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