"Shame on the United States for doing that," Huntsman said during a gubernatorial debate.

"The United States government did not inform our regulators and did not inform the Northwest Compact," the regional body that regulates radioactive waste, Huntsman said. "Shame on them."

The U.S. Nuclear Regulatory Commission granted licenses for shipments of low-level radioactive waste into the country between 2004 and 2006. The shipments consisted of about 1,000 cubic feet of waste from a Mexican nuclear plant, and about 6,000 tons of radioactive material from Canada. Records do not indicate how much of that waste ended up buried at EnergySolutions' Tooele County facility.

Huntsman's Democratic opponent, Bob Springmeyer, suggested that "Somebody was asleep at the switch" at the state level, and let the radioactive waste from Canada and Mexico slip into the state.

"I don't think that's under the radar, I just think that's immoral and illegal," Springmeyer said of foreign waste that was allowed to be buried in Utah because it had been processed at a facility in Tennessee. "To have waste come in from Mexico, maybe under the radar, certainly wasn't being observed by federal regulators, I think was inappropriate and negligent and, again, wouldn't happen under a Springmeyer administration."

Jill Sigal, spokeswoman for EnergySolutions, said that the residual waste from foreign material that has been processed in the United States is considered domestic waste and can be disposed of at the company's facility in Clive.

"[Springmeyer] needs to change federal law. EnergySolutions is complying with the law," she said.

"I can understand if there's a difference of opinion on whether those regulations and the federal law should be changed. People have a right to that opinion. But EnergySolutions is a company that is following the rules, following the regulations and following our license from the state of Utah."

Sigal said there is a transparent public comment period on import licenses.

NRC import-license officer Steve Dembek said Monday that the agency typically notifies the state when it approves "significant" shipments of foreign waste, but doesn't have a firm threshold for notification.

In the future, the agency plans to notify states and regional regulators of shipments of imported waste.

Huntsman said that, ultimately, he wants to see the flow of radioactive waste to the state come to an end. To do that, he said he has negotiated with the company a firm cap on the amount of waste that could be buried at the Clive, Utah, facility before it closes.

"I told the Northwest Compact that I want the [EnergySolutions] site to phase out to a date certain and no more will come into the state," Huntsman said. "I don't care if it's from Italy or Kansas."

Sigal said the company believes that gives them 30 more years of operation and potentially more if the technology improves.