Nuke panel finds errors in DOE plan

Wednesday, May 30, 2001 | 10:21 a.m.

The Nuclear Regulatory Commission staff has identified numerous errors in the Department of Energy's plan for how a high-level nuclear waste repository at Yucca Mountain would perform over thousands of years.

Nevada and Clark County officials called the findings significant, but DOE officials said the errors should not affect their predictions on how Yucca Mountain, 90 miles northwest of Las Vegas, would behave over time.

Yucca Mountain is the only site under study as the nation's high-level nuclear repository for burying 77,000 tons of commercial spent fuel and radioactive wastes from developing nuclear weapons.

Under eight topics detailed in a May 17 letter, the NRC's high-level nuclear waste branch Chief William Reamer explained the errors discovered by commission staff using DOE's computer models and hand calculations.

"NRC has asked DOE to determine the scope of these errors to evaluate the implications for the quality and adequacy of DOE's performance assessment," Reamer said.

The DOE is investigating how the errors in calculations and missing information could affect the quality and adequacy of its scientific data, officials said. Further meetings between the NRC and the DOE are scheduled in June.

The NRC wrote the letter after two conference calls between the agencies on May 4 and 9. The DOE confirmed the errors on May 9.

Reamer said the DOE erred in calculating the chemistry inside the waste packages. If there is higher acid content than the DOE expects inside the buried containers, all waste packages could fail sooner, perhaps within 1,000 years, allowing radiation to escape the site.

The NRC staff also noted that radiation doses are underestimated. While Don Kalinich of DOE said the error comes from using the same figures twice, Reamer noted that the radiation exposure numbers were 12 times lower than expected if a volcanic eruption swept through the repository at 500 years.

The DOE is checking its calculations and will report to the NRC in the coming months, said Steve Brocoum, the Yucca Mountain Project assistant manager for the Office of Licensing and Regulatory Compliance.

State and county officials who oppose the repository said the DOE's errors are significant.

Correcting the errors could delay the licensing hearing before the NRC, which will determine whether a Yucca Mountain repository would open by 2010, said Bob Loux, director of the state's Agency for Nuclear Projects.

"The DOE will have to revise every single calculation, and that could delay the licensing," Loux said.

"If this is an example of the sound science that the decision will be based on," County Nuclear Waste Division Director Irene Navis said, "then Nevada residents have every right to object to the disposal of nuclear waste at Yucca Mountain."