Documents reviewed by state officials "clearly show Sandia has subordinated safety and scientific accuracy to meeting an artificial deadline set by DOE," according to the 12-page complaint filed by Attorney General Catherine Cortez Masto.

In one undated e-mail to members of his team, a Sandia group manager said his responsibility "is to ensure that the 3 priorities -- schedule, defensibility, credibility -- in that order, are satisfied."

"If we do not meet the June 30 deadline, 'we are all out of a job,'" the manager wrote. "Any slips in schedule will be recovered by cutting scope. There is no allowance for not meeting schedule."

Another undated document forwarded to the Nuclear Regulatory Commission appeared to be notes from a meeting on Oct. 2, 2006.

"Sandia will not let DOE down," the typed note said. "We will meet this schedule. Delays are not acceptable."

Because of several missteps and missed deadlines over years at Yucca Mountain, the Bush administration last year put former nuclear industry executive Ward Sproat in charge of the project.

Sproat made changes and a commitment to Congress that a repository license application will be finished by no later than June 30, 2008.

The complaint filed by Masto charged that meeting a hard deadline "will take on overriding importance, and safety will get shortchanged."

The material discovered by the state "shows this is precisely what has happened at Sandia," the state's complaint said.

"Nevada's allegations are baseless," Energy Department spokesman Allen Benson retorted. "Quality and schedule are not mutually exclusive. Sandia National Laboratories is a world-renowned scientific institution."

"DOE will submit a high-quality license application and defend it during the Nuclear Regulatory Commission's licensing proceeding," Benson said.

Bob Loux, executive director of the Nevada Agency for Nuclear Projects, said the two documents were found when analysts reviewed Energy Department material in a database of Yucca Mountain documentation.

The state is looking through government paperwork for ammunition to fight the proposal to establish a nuclear waste site at the mountain ridge, 100 miles northwest of Las Vegas.

Sandia was hired in January 2006 to prepare safety analyses that underpin the Energy Department's bid to license an underground repository in Nevada. The site is to store highly radioactive used fuel from commercial nuclear reactors and other forms of nuclear waste.

"Sandia is confident in the integrity of its work and its management of this effort," contractor spokesman Michael Padilla said Tuesday. "Sandia believes the nation and citizens of Nevada can be confident in the quality and integrity of the post-closure safety analysis."

Nevada has filed seven petitions with the Nuclear Regulatory Commission since 2002 in seeking changes in the agency's Yucca Mountain procedures or to point out perceived flaws in Energy Department preparations for what are expected to be long and contentious license hearings.