Updated

Government employees may have falsified documents related to the Yucca Mountain (search) nuclear waste project in Nevada, the Energy Department said Wednesday. The disclosure could jeopardize the project's ability to get a federal permit to operate the dump.

During preparation for a license application to the Nuclear Regulatory Commission (search), the department said it found a number of e-mails from 1998 through 2000 in which an employee of the U.S. Geological Survey "indicated that he had fabricated documentation of his work."

Energy Secretary Samuel Bodman (search) said the department is investigating what kind of information was falsified and whether it would affect the scientific underpinnings of the project.

"If in the course of that review any work is found to be deficient, it will be replaced or supplemented with analysis and documents that meet appropriate quality assurance standards," said Bodman. He said he was "greatly disturbed" by the development.

The department said the questionable data involved computer modeling for water infiltration and climate at the Yucca site, which is 90 miles northwest of Las Vegas.

At a House hearing Wednesday, the official who recently took over the Yucca program in the Energy Department (search) indicated that the revelations could further delay the project.

"I assure you we will not proceed until we have rectified these problems," Theodore Garrish told Rep. David Hobson, R-Ohio, chairman of the House Appropriations subcommittee that controls the dollars for Yucca Mountain.

Garrish was not asked to elaborate. After the hearing, he declined to answer reporters' questions.

Hobson said the problem did not appear too serious and that he did not think it would throw Yucca Mountain off track.

"As I understand it this is not a major impediment and can be corrected very easily," Hobson told reporters. "Some people just don't want to do their job right, so they'll slip it through rather than doing their job. We don't have any evidence that somebody directed anybody to do this."

Chip Groat, director of the Geological Survey, said the e-mails "have raised serious questions about the review process of scientific studies done six years ago."

The disclosure follows other setbacks for the proposed waste dump. The department has delayed filing its license application to nuclear regulators and now acknowledges that the planned completion of the facility by 2010 no longer is possible. Garrish told the committee Tuesday that he couldn't provide a new completion date.

Congress last year refused to provide all the money sought by the Bush administration for the project. A federal appeals court rejected the radiation protection standards established by the Environmental Protection Agency; the agency is developing new standards.

Last month, the official in charge of the Yucca project resigned, citing personal reasons.

The discovery of the e-mails "really casts the project in a real bad light. In lieu of the other problems, it might be the one that pushes it over the edge to cancellation," said Bob Loux, Nevada state Nuclear Projects director and Gov. Kenny Guinn's chief anti-Yucca administrator.

Loux said potential water transport — the issue that some of the questionable work apparently involved — is critical for the proposed waste repository.

Water is "the key mechanism at Yucca Mountain both in terms of infiltrating into the site and in terms of letting radioactivity release into the biosphere," Loux said.

Word that documents may have been falsified "certainly calls into question DOE's ability to submit any kind of a license application in the near term," Loux said.

In a statement, Senate Minority Leader Harry Reid, D-Nev., said the development "proves once again that DOE must cheat and lie in order to make Yucca Mountain look safe."

Bodman said the questionable documents were part of the papers required by the NRC to verify the accuracy of earlier work in the project.

"The fact remains that this country needs a permanent geological nuclear waste repository, and the administration will continue to aggressively pursue that goal," Bodman said. He said that "all related decisions have been, and will continue to be, based on sound science."