The hearing was triggered by the plans of Louisiana Energy Services to build and operate a uranium enrichment facility near Eunice, N.M. A waste product would be what is termed "depleted uranium," which environmental activists say is a misnomer because it remains radioactive.

Depleted uranium has been stripped of the isotopes U-235 and U-234 for use elsewhere, but it retains the radioactive isotope U-238. According to Gulflink, a federal government Web site concerning Gulf War Syndrome, depleted uranium's chemical properties are more worrisome than the relatively low radioactivity.

Public Citizen, the institute and other environmentalists assert that the radioactivity is too high for disposal in shallow burial.

Depleted uranium waste from the proposed New Mexico plant could be taken to a disposal facility proposed for a few miles away in Texas. But an environmental impact statement issued in June says, "Envirocare accepts waste from all regions of the United States. Envirocare is licensed by the state of Utah to accept for disposal Class A waste only. Therefore, Envirocare is a disposal option for radioactive waste generated" at the proposed National Enrichment Facility.

Jason Groenewold, director of the activist group Healthy Environment Alliance of Utah, said Envirocare sent a letter to LES, saying the company could dispose of the depleted uranium. The letter is posted on the Internet.

"At the same time Envirocare was telling Utahns it was giving up pursuit of hotter radioactive waste, they were quietly working behind the scenes to solicit bulk quantities of depleted uranium," he said. According to Groenewold, experts say "it is hotter than Class C radioactive waste, which the Legislature just banned."

Arjun Makhijani, president of the Institute for Energy and Environmental Research, believes depleted uranium from the enrichment plant would be equivalent to "the kind of wastes that are being disposed of in the Waste Isolation Power Plant in New Mexico, the deep geological repository."

Eventually, if LES material is given shallow burial, wind could erode the covering and expose the depleted uranium, he said. That may take hundreds of years, but the half-life of the depleted uranium is much longer, he said.

"Our calculations show that the radiation doses would be hundreds of thousands of times the maximum allowable, under the commission's criteria," Makhijani said. If the material is exposed someday, he added, "you've got a very irradiated landscape."

Depleted uranium is considered Class A only because that's a sort of default classification, he said. Now the classification may be reconsidered. "It's a very big legal tangle right now," Makhijani said.