WASHINGTON - As one of her last official acts, Utah Gov. Olene Walker and governors of four Western states urged the Energy Department to remove the 10.5 million-ton Atlas uranium tailings pile from the banks of the Colorado River near Moab.

“There is broad support for moving the tailings from local, state and federal stakeholders that have toiled for several years to achieve that goal. É We want to make it clear that any remediation other than an off-site option is unacceptable,” Walker wrote in a letter approved by the four state governors, including California Gov. Arnold Schwarzenegger.

Contaminants from the mountain of uranium tailings have been seeping into the groundwater and the nearby Colorado River, threatening endangered fish and alarming downstream water users.

The river provides water for more than 25 million people in Arizona, Nevada and California.

The governors of all three states approved the letter, along with New Mexico Gov. Bill Richardson, who was the Energy Secretary under President Clinton.

Cleanup stalled when the Atlas Corporation declared bankruptcy in 1998, leaving behind an interim cap over the pile and inadequate cleanup fund. Since then cleanup has lurched along sporadically. In 2000, Congress passed legislation assigning the Energy Department the task of solving the problem.

Under one proposal, the tailings would be covered with an earthen cap to prevent them from being disturbed and then efforts would be made to prevent further contamination of the river and groundwater.

But governors and members of Congress from the Southwest insist the pile be moved from the river to stop the contamination and remove the risk that a flood could wash the pile downstream.

"You've got the governor of every state along the Colorado, from where the tailings pile is located on downstream, saying, 'Hey, we don't think this is an acceptable risk to leave this stuff here.' And I fully expect there will be a similar letter from every senator along the river and the members of the House," said Bill Hedden, executive director of the Grand Canyon Trust, the environmental group in favor of moving the pile.

"Where you have so many of the leading elected officials weighing in and saying move it, maybe that means something."

The Energy Department, which has been assigned by Congress the task of solving the problem, issued a draft environmental study in November, but the department did not endorse either option.

Capping the pile would cost about $166 million and take between seven and 10 years. Moving the tailings would cost $436 million and take eight years to complete. Either option would require roughly $11 million in additional groundwater remediation.