Auditors say flaws and shortcomings in technical documents could delay licensing a national nuclear waste repository the Energy Department wants to open in the Nevada desert.
A Nuclear Regulatory Commission report concludes that unless the Energy Department changes procedures, regulators won't have the information needed to weigh a license application the department plans to submit by December.
"This could result in the NRC issuing a large volume of requests for additional information in some areas," commission auditors said in the report issued Tuesday.
A delay in obtaining the license could delay Energy Department plans to open the Yucca Mountain repository in 2010.
Nuclear Regulatory Commission evaluators spent three weeks in Las Vegas from November to January reviewing how the Energy Department and its contractors were compiling the repository license application.
The Energy Department expects to submit more than 3 million pages of documents to prove the Yucca Mountain repository 90 miles northwest of Las Vegas can safely entomb 77,000 tons of radioactive spent fuel and nuclear waste.
After examining analysis model reports for three of more than 120 segments of the project, auditors said they found parts of DOE's work were unclear. In some areas, explanations were clear but background documents were lacking, the auditors said.
Inspectors examined documentation for studies on how waste canisters will corrode over time and how radioactive particles in the waste material will disintegrate. They also reviewed analyses on how long it may take for repository tunnels to collapse.
The Energy Department plans to spend 24 years accepting shipments at Yucca Mountain from 127 sites in 39 states, and then seal the repository. It would remain radioactive for tens of thousands of years.
The Nuclear Regulatory Commission team also confirmed that Energy Department and Bechtel SAIC, the project's managing contractor, have not been able to eliminate quality assurance mistakes. But the auditors said the technical information was improved from a 2001 assessment.
On the Net:
Yucca Mountain Project: www.ymp.gov
Nuclear Regulatory Commission: www.nrc.gov