THURSDAY, April 25, 2002 (HealthDayNews) -- A House committee voted overwhelmingly today to bury the nation's nuclear waste deep underground in Nevada amid a new scientific call to proceed with caution.
The House Energy and Commerce Committee voted 41-6 to approve shipping 77,000 tons of high-level waste to the Yucca Mountain site over vehement objections from Nevada residents and anti-nuclear activists. The measure moves to the full House and then to the Senate, where a tougher battle is expected.
Meanwhile, two researchers are arguing that the government knows too little about the science of the project -- and thus its safety -- to proceed. They also argue that the debate has been pushed faster by politics, since the Sept. 11 terrorist attacks left managers of nuclear facilities feeling vulnerable.
"There are some difficulties that make the site marginal at best," said Rodney Ewing, a University of Michigan geologist and nuclear engineer. "If we want to go forward with this site, we really have to understand the mountain better."
Ewing and a colleague, Allison Macfarlane of the Massachusetts Institute of Technology, offered their case for caution in an essay in the tomorrow's issue of Science.
"With further study, Yucca Mountain may be judged to be an adequate site for the disposal of nuclear waste, but a project of this importance, which has gone on for 20 years, should not go forward until the relevant scientific issues have been thoughtfully addressed," the researchers wrote.
In February, President Bush announced his selection of Yucca Mountain as the destination for the nation's nuclear waste.
The nation's nuclear waste is currently being held in 131 temporary ground-level storage facilities scattered across 39 states. If Congress and the Nuclear Regulatory Commission approve the Yucca site, the government in 2010 will begin a decades-long project of burying the highly radioactive material in the mountain.
William Beecher, a spokesman for the NRC, said his agency had sent the Energy Department more than 200 questions to address before it would be willing to grant a construction permit for the Yucca Mountain facility. That application is expected sometime in 2004.
The repository would be about 1,000 feet below the surface and about the same distance above the water table.
Underground storage has become a consensus choice of graveyard for the world's nuclear waste, although Yucca Mountain would be the first such facility. The waste includes spent fuel from power plants and, to a smaller extent, radioactive material generated in the processing of uranium and plutonium for reactors and weapons.
A chief criterion for where nuclear waste rests is that the repository must be dry. Water offers a vehicle to shuttle radioactive atoms away from the site and into the environment.
In a letter to Bush recommending Yucca Mountain, Energy Secretary Spencer Abraham said he "could not and would not recommend the Yucca Mountain site without having first determined that a repository at Yucca Mountain will bring together the location, natural barriers and design elements necessary to protect the health and safety of the public."
When Yucca Mountain, which sits beside the Nevada Test Site -- a former proving ground for A-bomb blasts -- was initially chosen from among several other candidates, it was assumed to be dry. But Ewing said that assumption has proven flawed with the discovery relatively deep in the mountain of radioactive chlorine created in nuclear tests in the middle of last century.
If radioactive chlorine could travel via water into the mountain so quickly, Ewing said, it's possible it could exit that rapidly, too. Whether it will needs to be determined, he added.
If the natural barriers of Yucca Mountain don't live up to their initial promise, the burden of keeping the radioactive waste out of the water table and the environment beyond will fall on the durability of the engineered barriers, Ewing said.
The primary shield is a metal alloy safe designed to resist corrosion. But while Energy Department officials "take considerable credit for the longevity of the waste package," Ewing said, whether it's sufficient in the context of a porous rock bed is uncertain.
"If you take away a few of the [natural] barriers, it could happen that the repository would fail to meet the regulatory requirements" for safety, Ewing said. "If the repository doesn't meet the regulatory requirements, that's a national problem."
The safety regulations governing Yucca Mountain are based on models of how the waste might behave over a period of 10,000 years, and include everything from the level of volcanic and seismic activity at the site to how quickly radioactivity might reach a valley 20 kilometers away.
Environmental Protection Agency standards require that a person living 11 miles from the storage site not be exposed to more radiation from it each year than someone who makes three round-trip flights from Las Vegas to New York.
Officials at the Department of Energy did not return calls seeking comment on the Science paper.
Chris Whipple, an environmental consultant who has been involved in the Yucca Mountain project since 1985, said he believes the site is a reasonable one to house nuclear waste. "It has a historical use that suggests that we're not taking a pristine area and screwing it up. The second [reason] is that it's dry and away from people."
However, Whipple, whose firm, Environ, is in Emeryville, Calif., said the government needs to address several issues before it can go ahead with building the facility. Foremost among these, he said, isn't water flow but the vulnerability of the metal casing -- and an umbrella-like drip shield of stainless steel that will ultimately protect the casing from seepage -- to corrosion.
Sue Gagner, an NRC spokeswoman, said the issues Ewing and Macfarlane raised were included in the questions her agency sent to Energy officials about its plans for Yucca Mountain. The agency has responded to almost 40 of those queries so far, Gagner said.
What To Do
For more on Yucca Mountain, visit the Department of Energy's U.S. Office of Civilian Radioactive Waste Management.
For an opponent's point of view of the Yucca site, click on the Web page of U.S. Sen. Harry Reid, a Democrat from Nevada.
