Chris Schneidmiller
WC Monitor
1/15/2016
The Department of Energy is politely pushing back against new research suggesting rock salt might not be a fully safe for underground storage of nuclear waste in New Mexico.
Salt beds are used for storage of low-level nuclear waste at the Waste Isolation Pilot Plant and have been considered as an option for future storage facilities in the United States. They are also employed for the same purpose at one existing repository and one proposed site in Germany. The idea is the salt would act as a “sealant” against environmental contamination should the radioactive material escape the storage containers.
However, University of Texas at Austin researchers said in a November article in Science magazine that field and lab testing showed rock salt might be more permeable than thought due to “deformation” of the subterranean material. A press release from the university’s Cockrell School of Engineering specifically noted WIPP in addressing the potential vulnerability of nuclear waste stored in rock salt.
“As a regulated facility, we take any challenges to our safety basis seriously. So as soon as we heard about this article in Science we contacted our subject matter experts … and got them to review the article and write us their impression of the article,” Abe Van Luik, a DOE senior physical scientist in Carlsbad, said during a Jan. 7 town hall meeting on WIPP.
Department site characterization research for WIPP from the 1980s and 1990s directly addresses the salt deformation issues raised by the research article, according to Van Luik. The natural salt beds in which WIPP was mined have been shown to be stable for 225 million to 250 million years, he said. WIPP opened for transuranic waste storage in 1999; it has been closed since a fire and radiation release in February 2014, but DOE has vowed to resume waste emplacement this year.
The department also noted that the Environmental Protection Agency every five years analyzes shifts in geological conditions and practices at WIPP for recertification. “EPA has continued to determine that the facility meets its performance objectives and all the requirements of EPA’s disposal regulations,” a DOE spokesperson said by email.
Scientists from the DOE’s Sandia National Laboratories and peers from Germany have been preparing a response to the Science article, Van Luik said. But they’ve changed toward what they hope will be a friendlier approach – collaborating with the UT researchers on a follow-up article showing that the issues they raised were addressed prior to the construction of the U.S. and German storage sites.
“So what we’re going to do on the 12th is I’m orchestrating a conference call with the University of Texas people, with the Germans, and with us, and we’re going to calmly talk through their recommendations, and show them, and give them references, to where we did this work,” Van Luik said. The conversation is not intended to question the university researchers’ work, which the DOE scientist called good science that “was just inappropriately extended to our case.”
“What we’re hoping to do is convince them that it would be a win-win situation for all concerned, and put this issue to bed, if they would acknowledge in that response article, that DOE has shown to their satisfaction that WIPP is a very stable site,” Van Luik said.
Marc Hesse, a computational geoscientist who worked on the UT research project, confirmed Wednesday that the teleconference occurred. “Abraham Van Luik from the DOE Carlsbad office is preparing the notes,” he said by email. “We have decided to spend some time thinking about each other’s points of view, exchange some papers and see where it goes.”
