WASHINGTON -- The Nuclear Regulatory Commission on Wednesday granted Nevada 30 additional days to file license challenges to the Yucca Mountain repository, short of the extra time the state requested for its preparations.

Attorneys for the state asked the nuclear safety commissioners in April to allow 180 days for participants in license hearings to file "contentions" that challenge aspects of the nuclear waste plan. NRC rules currently allow 30 days.

In a seven-page order, the four-member commission said 180 days was too long to alter long-standing rules.

But they agreed to allow an additional 30 days as a "modest extension of time." On top of the 30 days already allowed, this means the state and other participants in Yucca licensing would have 60 days to file contentions.

The clock starts ticking after the NRC decides whether it will docket and hold hearings on a Yucca Mountain repository application. If the agency decides to move forward, the 60-day period starts when it files a formal notice of hearing.

The agency is expected to announce a docketing decision early next month.

Bob Loux, executive director of Nevada's nuclear projects agency, said he welcomed whatever extra time the NRC granted.

"We would have wanted a lot more time but we are grateful we got at least some time," Loux said. "Candidly, we were preparing we would get denied in total."

Nevada attorneys have said they might file between 250 and 500 contentions on various elements of the Yucca program in a bid to kill or further delay the project.

Those numbers of contentions would be a record for a nuclear license application, although attorneys say they expect only a portion will be accepted for discussion.

The Department of Energy on June 3 sent the NRC volumes of studies supporting its application to build the Nevada repository to hold 70,000 metric tons of high level radioactive waste from commercial power plants and government weapons sites.