Bush oil shale rules roil Mountain West

Seven weeks after a congressional moratorium on oil shale development expired, the Bush administration has issued rules that take the first step toward tapping an estimated 800 billion barrels of oil trapped in sedimentary rock in Wyoming, Utah and Colorado.

The new rules have highlighted a divisive partisan issue among western politicians, with Republicans ready to push forward with development and Democrats urging a more cautious approach. The rules establish a framework for how energy companies will lease federal land for oil shale mining. Opponents say oil shale mining uses so much water that it could threaten their drinking water supply. They also say its heavy consumption of energy could outweigh its energy benefits.

Oil shale is a sedimentary rock that contains trace amounts of oil, which can be extracted at high temperatures. But turning shale into usable oil is expensive, and the industry hasn