Sen. Harry Reid called for an immediate work shutdown at the Yucca Mountain nuclear waste project until inspectors determine whether rock tailings piled outside the repository tunnel pose a health hazard.
Reid, D-Nev., said Wednesday the tunnel and other portions of the work area should be sealed off until the Energy Department "can gauge what the problem is and determine whether it is safe."
Energy Department officials did not immediately respond Thursday to a request for comment.
Nevada's environmental protection administrator, Allen Biaggi, told the Las Vegas Review-Journal this week that a state inspector will examine volcanic rock tailings unearthed during excavation of the 25-foot diameter tunnel between 1994 and 1997.
Biaggi agreed to have the tailings inspected after former Yucca Mountain workers blamed lung problems on toxic dust inhaled during tunneling work at the site, 90 miles northwest of Las Vegas.
Congress in 2002 approved building a national nuclear waste dump at the Yucca Mountain site. The Energy Department wants to begin storing spent nuclear fuel from around the nation at the site beginning in 2010, and plans to submit an application for an operating license to the Nuclear Regulatory Commission later this year.
The state, which opposes the Yucca Mountain project, has the authority under the federal Clean Air Act to inspect the tailings piled outdoors as a possible air quality hazard.
Reid said he was awaiting a response from Energy Secretary Spencer Abraham to a Jan. 29 inquiry about health and safety protections at the Yucca site.
The Energy Department acknowledged last month that workers may have been exposed to fibrous silica dust during tunnel excavation, and offered free health screenings for silicosis, a lung disease.
Jacob Paz, a former federal Occupational Safety and Health Administration hygienist who was a contractor on the Yucca Mountain project, said Wednesday he warned the Energy Department in 1991 about hazards from the mineral erionite at the site.
He said his memo advised the Energy Department that erionite is a carcinogen that posed an occupational health hazard.
Three other Nevada's federal lawmakers backed Reid's call for Yucca Mountain work to stop.
"I'd love to see that happen, but I don't expect it," said Sen. John Ensign, R-Nev.
Rep. Shelley Berkley, D-Nev., compared Yucca Mountain workers with Nevada Test Site workers who contracted silicosis after tunneling for underground nuclear weapons tests.
Congress in 2000 and 2001 passed bills offering $150,000 compensation to nuclear workers in Nevada and other states who contracted silicosis, chronic beryllium disease or cancers that could be traced to job-related exposures.
Berkley and Rep. Jon Porter, R-Nev., said they were researching whether Yucca Mountain workers qualify under the nuclear worker law.
Porter said that if reviews show shoddy work at Yucca Mountain, "we will elevate it to the other members (of Congress) so they realize what is happening."