The chemical reaction that shut down the nation’s main nuclear waste disposal plant may have been caused by allowing materials, which most chemists know are not compatible, to be mixed.
The New Mexico Environment Department has made public online internal Los Alamos National Laboratory emails showing Los Alamos approved products to be used in the drums that some experts say contain ingredients widely known to cause a heat reaction when combined with the drums’ other contents.
The emails are not about the switch from inorganic to organic cat litter – a top theory of what caused the hot reaction at the Waste Isolation Pilot Plant near Carlsbad.
These emails pertain to other organic materials approved for use in the drums.
Environment Secretary Ryan Flynn said the department is looking at how decisions were made on changes in the contents of the drums.
“This issue is one that we are pushing for answers on,” he said.
The federal Department of Energy has been investigating why and exactly what occurred at WIPP on Feb. 14, when a chemical reaction damaged the lid on at least one drum, allowing radiation to escape the deep underground repository. The state Environment Department is looking into whether state safety regulations were violated.
WIPP, the nation’s primary permanent storage facility for the leftovers of Cold War-era nuclear weapons testing, has been shut down since an unrelated truck fire struck underground Feb. 5.
Following the Feb. 14 radiation leak, WIPP managers have said the plant could be closed for up to three years, leaving the nation nowhere to send certain types of nuclear waste.
The emails trace LANL’s approval of two products requested by contractor EnergySolutions, which packages LANL waste, to neutralize the pH balance of drum contents sent to WIPP.
The products contain organic ingredients known to be incompatible with the nitrate salts present in the LANL waste containers – “a bad combination,” according to Cole Smith, a chemist in NMED’s Hazardous Waste Bureau.
EnergySolutions asked LANL managers for approval in a May 2013 email to switch to one of the products. LANL approved the change a month later – despite product warnings clearly stating that the product is incompatible with metallic nitrates and “strong oxidizers,” such as nitrate salts, both of which are found in the LANL drums.
Nitrates and organic matter are known to oxidize, a reaction that generates heat.
The other product mentioned in an email was a new liquid to neutralize acids and bases in the drums. When Zeke Wilmot, EnergySolutions industrial hygienist, asked in an August 2013 email for approval to use the product, he notes that “criticality safety issues are not my area of expertise” and “it may be advisable to have LANL personnel weigh in on these issues as well.”
A subcontract technical representative for LANL environmental programs responded to Wilmot and approved the change in a September 2013 email copied to eight other people. The approved product also contains an organic ingredient.
“It wasn’t the most fantastic choice because nitrate salts in combination with organics is a bad mixture,” said Smith, who also serves on the NMED team that writes the permit for WIPP.
“That might be the problem right there,” said William Quintana, head of the New Mexico State University chemistry department. “Nitrates are oxidizers. Every chemist knows that.”
WIPP and LANL did not grant requests for interviews regarding the emails released by NMED. EnergySolutions did not respond to requests for information or an interview on the waste packaging process at LANL.
A LANL spokesman emailed a statement saying, “We’re looking into all possible causes and will continue to do so until we are satisfied that we know what caused the radiological release.” A WIPP spokeswoman emailed a statement saying, “We continue to investigate the details” of the radiation release.
Smith said the WIPP permit does not detail procedures for the neutralization process or for obtaining neutralizing products, and NMED was not involved in either purchasing decision.
The emails also don’t say what kind of testing may or may not have been done at LANL before the products were approved, said Don Hancock of the Southwest Research and Information Center, a WIPP watchdog.
“There is no way anyone can make a big change without it going through a lot of people,” Hancock said. “There are multiple people who were aware of this in 2013.”
NMED requested the emails as part of its investigation into how product choices were made by DOE and its contractors. While Flynn said the cat litter theory remains the most viable, NMED’s goal, he said, is about “understanding what happened and whether they deviated from the regulations.”
“It doesn’t really matter who is to blame,” he said. “They all work for DOE.”