Nuclear Waste Solution Seen in NM Desert Salt Beds

Half a mile beneath the desert surface, in thick salt beds left behind by seas that dried up hundreds of millions of years ago, the Department of Energy is carving out rooms as long as football fields and cramming them floor to ceiling with barrels and boxes of nuclear waste. The salt beds, which have the consistency of crumbly rock so far down in the earth, are what the federal government sees as a natural sealant for the radioactive material left over from making nuclear weapons. The process is deceptively simple: Plutonium waste from Los Alamos National Laboratory and a variety of defense projects is packed into holes bored into the walls of rooms carved from salt. At a rate of six inches a year, the salt closes in on the waste and encapsulates it for what engineers say will be millions of years. “It’s eternity,” said Dirk Roberson, a guide for the frequent tours the Energy Department gives to visitors to the salt mine, who leave with a souvenir plastic bag filled with chunks of salt pressed into rocklike form. The complications of the present intruded last week, however, when a truck hauling salt in the mine caught fire. Smoke forced an evacuation of workers and a shutdown of waste burial operations, which officials said was temporary. They said the fire did not affect the radioactive waste, which is stored at the other end of the mine. Despite the setback, the Waste Isolation Pilot Plant, WIPP for short, is drawing new attention here in the New Mexico desert. At a time when the effort to find a place for highly radioactive civilian and military wastes is at a near-standstill, officials say the site might be a solution. It is of particular interest since the demise of the plan for Yucca Mountain, a volcanic ridge 100 miles from Las Vegas chosen by Congress for the storage of nuclear waste from power reactors and weapons, but adamantly opposed by the state of Nevada. Some people despair of finding a place for what officials call a high-level nuclear “repository” — they shy away from “dump” — but Allison M. Macfarlane, a geologist who is chairwoman of the Nuclear Regulatory Commission and who served on a presidential study commission established after the Yucca plan was canceled, said WIPP proves it can be done. “The main lesson from WIPP is that we have already developed a geologic repository for nuclear waste in this country, so we can in the future,” she said. The key, she said, is a site that is acceptable to both scientists and the local community. The salt at WIPP is not much different from what goes into food. Phillip R. Sharp, who served on the same study commission as Ms. Macfarlane, said that when the group visited Carlsbad, about 25 miles west of the site, commission members were served cocktails — margaritas garnished with salt from the repository. But the salt behaves strangely around nuclear waste, which is warm to the touch. When the waste is buried in salt, tiny bits of water inside the salt start to move toward the heat. As a result, the salt left behind is stronger, like a good sealant. But it is still basically salt. “The salt is completely unaffected by any nuclear waste you could imagine, period,” said James Conca, a geologist and former director of the Carlsbad Environmental Monitoring and Research Center, a division of New Mexico State University. With most things nuclear, however, the politics can be trickier than the science. In the case of WIPP, there is local support but skepticism farther afield...more