In Washington, Energy Secretary Samuel Bodman issued a written statement regarding the falsification claims. "I am greatly disturbed by the possibility that any of the work related to the Yucca Mountain project may have been falsified," he said Wednesday.

Little construction has occurred at Yucca Mountain. It has not yet received a license, but in July 2004, a federal appeals court ruled in favor of the site. "Our scientific basis for the Yucca Mountain project is sound," Spencer Abraham, then the secretary of the U.S. Department of Energy, said in response to the dismissal of the legal challenges.

But now the repository's scientific studies are being called into question.

On Wednesday, Chip Groat, director of the U.S. Geological Survey, said e-mails by USGS employees raised serious questions about the review process of scientific studies done six years ago on the site.

Doubts now exist about studies in the 1998-2000 period regarding the likelihood of water seeping into the repository. Employees are alleged "to have committed improprieties after moving into the quality assurance phase" needed for the U.S. Department of Energy's licensing process, says a DOE press release.

"The e-mails indicated that employees involved in studies of water infiltration and climate may have falsified documentation of their work."

Groat said these were serious questions about quality assurance practices. "Two actions are under way to investigate these issues," he said.

"First, I have referred the matter to the inspector general (of the Interior Department) for action. Second, I have initiated an internal review of the allegations."

Once the facts are known, Groat added, "appropriate actions will be taken."

Neither the DOE nor the USGS would speak on the record about the matter, other than official written statements.

A DOE release faxed to the Deseret Morning News said the documentation in question relates to computer modeling involving water infiltration.

"During the document review process associated with the Licensing Support Network preparation for the Yucca Mountain project, DOE contractors discovered multiple e-mails written between May 1998 and March 2000 in which a USGS employee indicated that he had fabricated documentation of his work," said Bodman's formal statement.

The DOE has started checking the data in the study and the documentation that was used. If any work is found deficient, "it will be replaced or supplemented with analysis and documentation that meets appropriate quality assurance standards," he added.

In addition, all of the work completed by anyone identified is being thoroughly reviewed "to ensure that other work was not affected," he said.

Bodman called behavior indicated in the e-mails "completely unacceptable."