WASHINGTON -- Scientists working for Nevada staged an experiment this morning that showed that water will not only drip through the rock and onto nuclear waste canisters stored at Yucca Mountain but mineral deposits from the water will cause the canisters to corrode.
Corrosion is a key point in the debate over Yucca Mountain. Critics of the site fear corrosion because if corrosion causes cracks or openings in a container holding nuclear waste, radiation can get into the groundwater underneath Yucca Mountain, 90 miles northwest of Las Vegas, that will eventually contaminate drinking water.
The Energy Department has said that the waste will be sealed and protected by the casks and shields placed over the casks.
But in live experiments done this morning at the National Press Club in Washington, D.C., Dr. April Pulvirenti of Catholic University and Dr. Don Shettel of Geosciences Management Institute in Boulder City demonstrated how water will move through the rock above the where the spent nuclear fuel will be stored inside Yucca Mountain and how once it hit the canisters it would eat through the metal.
"It will be many lifetimes before we face the repercussions of our actions but our descendents will be faced with an environmental diaster of epic proportions," according to a video prepared by the state outlining the experiments.
Nevada officials estimate that under the right conditions corrosion could start within 1,000 years.
The Energy Department says the casks will stay intact for at least 10,000 years, which the law calls for.
The Nuclear Energy Institute, the nuclear industry's lobbying group, says the waste casks will last 2 million years.
Shettel showed how water in the rock would boil and move through the tiny cracks in the mountain rock due to the heat the spent fuel will create.
Pulvirenti placed samples of Alloy-22, the metal planned to be used to make the waste storage containers, in glass flask of a concentration solution of minerals left from evaporated water. The first sample of metal corroded in about 20 minutes.
She used a water "recipe" based on what the department has said is in the water in the area above where the waste will be stored. If this water hits the waste canister, it will evaporate, leave the deposits that will accumulate over time and cause corrosion.
The scientist said the Energy Department has not done these types of experiments but instead has only looked at water underneath where the waste will be stored.
Energy Department officials could not be reached for comment this morning.
The Energy Department plans to have a "drip shield" made ot Titanium-7, another alloy, cover the waste containers, but other experiments by the state show that mineral deposits will corrode that alloy as well. A break in the shield would allow water to drip onto the water canisters.
Bob Loux, executive director of Nevada's Agency for Nuclear Projects, said the department has plans for the drip shield, which is estimated to cost $8 billion, and the state will argue during the licensing hearings at the Nuclear Regulatory Commission for a commitment that those shields will be put in place because without the shields corrosion could happen quicker.
Loux said the experiments show that it's "not only the criticisms of the state of Nevada, the Nuclear Regulatory Commission and the General Accounting Office that show they (Energy Department officials) don't have the science to show how Yucca Mountain will perform over time."
Allen Benson, a Yucca Mountain project spokesman, said the Energy Department has science to show the casks will perform.
"What the state of Nevada demonstrated this morning was good theater," Benson said. "Our experiments and analysis demonstrate that the waste package will provide a robust barrier in excess of 10,000 years."
The Nuclear Energy Institute says the states claims about the corrosion rates "are not valid."
"Claims of rapid corrosion ignore what is known about the repository environment," according to a statement from NEI, which released counter arguments to Nevada's experiments on Tuesday.
"Sound science concludes that the waste packages will last 2 million years in the repository," the group said.
The NEI said that conclusion is based on "studies of artifacts, cave paintings and animal remains, items less suited for long-term survival than Alloy-22."
The statement said that those studies have shown the items "have survived many thousands of years in environments far less favorable than that which will exist in Yucca Mountain."
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