More concerns raised over Yucca ground water

Tuesday, Dec. 18, 2001 | 8:48 a.m.

A Nevada consultant has raised new doubts regarding how fast deep ground water is moving beneath Yucca Mountain, the only site proposed to house 77,000 tons of the nation's high-level nuclear waste.

Information presented Monday by hydrologist Linda Lehman has prompted an independent National Academy of Sciences review panel to ask the Department of Energy about its plans to further study ground water underneath the desert between the mountain and U.S. 95, where Nye County plans to develop an industrial park.

If contaminated water escapes from a repository at Yucca Mountain, residents and the environment could be exposed to dangerous radiation levels. The DOE, by regulation, must design a site that will keep nuclear waste intact for 10,000 years.

Lehman presented the findings of two years of research Monday night that showed the possibility of hot water in faults deep beneath Yucca Mountain. Evidence of water was discovered by scientists with the U.S. Geological Survey and by Nye County drilling crews, Lehman said.

Water reaching the repository site could corrode buried metal containers, releasing radioactive waste, Lehman said.

The warmer water, while it was found more than 1,000 feet beneath the proposed repository, could pose a danger to buried waste because it appears to flow along three known earthquake faults, Lehman said. Two of the faults, the Ghost Dance and the Sundance, run through the repository site, she said.

The temperature of the warmer water, which is at least 10,000 years old, is between 123 degrees and 140 degrees Fahrenheit, Lehman said. Water boils at 212 degrees Fahrenheit.

The state, which opposes a Yucca Mountain repository, has "no confidence" in the DOE's estimate as to how the ground water behaves, Lehman said.

"I, too, am concerned about a large area with no information," Leonard Konikow, a USGS hydrologist and panel member, said of the area at Yucca Mountain. He asked Lehman how long it may take to find the source and volume of the water.

"I think it's a long-term commitment just to find out what's going on," she said.

How fast is the water moving? Konikow asked. "That's the $64,000 question," Lehman replied.

The DOE does not believe that water will move out of a Yucca repository for at least 10,000 years, federal scientists said. "We have a lot of data that backs up our (computer) models," said Mark Peters, Yucca coordinator at the DOE's Los Alamos National Laboratory in New Mexico.

The DOE must respond to the state's water analysis, William Boyle, licensing and regulatory adviser for Yucca Mountain, said.

This is not the first time independent scientists have questioned the DOE's lack of information about the mountain, 90 miles northwest of Las Vegas.

The Nuclear Regulatory Commission said it has 293 unresolved technical issues ranging from how fast water flows to the amount of volcanic activity at the mountain. Another panel, the Nuclear Waste Technical Review Board, has raised doubts about the DOE's overall analysis for designing a permanent repository.

The DOE is also asking the academy's 14-member panel for its opinion on building a nuclear waste repository in stages so flaws in the project could be identified and answered at an early point in construction.

Although DOE officials expected to recommend the site to President Bush by the end of the year, Energy Secretary Spencer Abraham said last week he has not made a decision on whether to recommend Yucca and has no deadline for such a decision.