The first shipment -- with 5,408 drums -- left South Carolina late Tuesday and is already on its way.
"There are three shipments, each with about a third of the total, with this shipment that left the state yesterday being the first," said Jen Stutsman, an Energy Department spokeswoman at the agency's Washington headquarters.
The remaining two shipments will be completed by next spring.
On Tuesday, Utah Gov. Gary Herbert wrote to Energy Secretary Steven Chu asking that the shipments be halted while potentially stricter disposal rules are evaluated.
"We received the letter late yesterday afternoon and would not have had the opportunity to stop the shipments," Ms. Stutsman said. "Each train takes a significant amount of time and labor to load."
Mr. Herbert's letter said Utah's Department of Environmental Quality is evaluating stricter regulations governing depleted uranium of the type being shipped from SRS to the EnergySolutions disposal facility in Clive, Utah.
Such waste, he noted, remains radioactive hundreds of years longer than other wastes buried at the site.
Currently, however, the shipment of such wastes to Utah complies with federal and state laws and licenses, according to the Utah Department of Environmental Quality.
"EnergySolutions has been disposing of low-level radioactive waste with relatively low concentrations of depleted uranium since 1991 and recently disposed of highly concentrated drums of depleted uranium from Savannah River Site," wrote executive director Amanda Smith, in a Dec. 1 letter to Frank Marinowski, DOE's deputy assistant secretary for regulatory compliance.
The site, Ms. Smith added, "is in compliance with the terms of its radioactive materials license and the Utah Radiation Control Rules."
She further wrote that while both Utah regulators and the U.S. Nuclear Regulatory Commission are considering changes that could require licensees to address funding for recovery and remediation of depleted uranium wastes, such rules remain in the study stages and have not been adopted.
The SRS waste now being moved is several years ahead of its original schedule because of the use of American Recovery & Reinvestment Act funds that have allowed many environmental and cleanup projects to move at a faster pace, she said.
"The DOE has been working closely with Utah Department of Environmental Quality to ensure that all of the shipments that occur are within the constraints of existing licenses," Ms. Stusman said. "What the state is looking at are options going forward, and what we can commit to doing in the future is staying within the confines of the licenses."
Associated Press reports were used in this article.
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