DENVER (AP) - The federal government's new plan for oil shale development on public lands would make almost half a million acres in Utah, Wyoming and Colorado available for research on how to commercially produce oil from oil shale.

The George W. Bush administration had made almost 2 million acres available, but federal officials took a new look after conservation groups filed a lawsuit alleging the government hadn't fully reviewed potential environmental impacts first.

A draft environmental impact statement released Friday says the preferred plan now is to make 35,308 acres in Colorado; 252,181 acres in Utah; and 174,476 acres in Wyoming available for research. Also, 91,045 acres in eastern Utah would be available for activities related to tar sands.

The public has until May 4 to comment on the proposal.

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