Copyright © 2014 Albuquerque Journal
The radiation leak that has shut down the nation’s only operating underground nuclear waste disposal site was, for all practical purposes, never supposed to happen.
No one knows yet how or why a waste drum leaked at southeast New Mexico’s Waste Isolation Pilot Plant on Valentine’s Day, triggering alarms, exposing workers and setting off a cascade of events that could cripple the nation’s radioactive waste disposal system.
But a Journal review of Department of Energy records shows that, before WIPP opened, the agency put the risk of such an accident at one chance in 10,000 to one in 1 million during any given year of WIPP operations.
WIPP, which was supposed to safely protect waste for 10,000 years, has been open just 15 years, noted Don Hancock, head of the Nuclear Waste Safety Program at the nonprofit Southwest Research and Information Center in Albuquerque.
Human waste handling mistakes, such as a forklift accident, were seen as the most likely way a leak might happen, according a 1997 review of WIPP underground accident scenarios.
Located outside of Carlsbad in southeast New Mexico, WIPP is a 2,150-foot deep salt mine that is a permanent disposal site for radioactive waste from U.S. nuclear weapons production. With a budget of $202 million this year, it employs more than 1,000 people.
But no people were in the WIPP underground repository on Feb. 14. That leaves only two possible scenarios among the leak risks studied in the 1990s for WIPP’s exhaustive Supplemental Environmental Impact Statement: an exploding waste drum or a waste disposal room roof collapse.
Officials overseeing the response to the Valentine’s Day leak have refused to say what they think might have caused the breach of a waste drum or drums, saying they are waiting until they get the results of a probe sent down to evaluate the situation. If the probes, sent down Friday, show a habitable environment, people will go down, according to Farok Sharif, president and project manager of Nuclear Waste Partnership, the contractor that runs WIPP for the federal government. If it’s unsafe, a Sandia National Laboratories robot will go in, Sharif said at a public meeting Friday in Carlsbad.
The notion that such leaks were essentially never supposed to happen in WIPP’s underground disposal areas was central to the project’s planning and design, explained Bob Neill, a radiation safety expert who from 1978 to 2000 headed the Environmental Evaluation Group, an independent state government WIPP watchdog. All the radioactive waste held in WIPP was supposed to remain fully contained in waste drums, with zero leakage. The mantra “start clean, stay clean” was one of the guiding WIPP design principles, said Neill in an interview.
Federal officials and independent monitors say the radiation that escaped WIPP was minimal, but as yet they have no idea how widespread the contamination is in the deep underground repository where the waste was supposed to have remained tightly sealed within immaculate, neatly stacked drums.
Regardless of how it happened, the detection of leaking radiation in the deep underground salt mine, and the uncertainty over how far and wide within the mine it spread, changes all that, Neill said. “You could have crapped up a whole lot of real estate down there,” Neill said.
The underground drum fire scenario, according to the 1997 safety analysis, hypothesized the “spontaneous combustion” of a drum’s contents, rupturing and spreading the radioactive waste inside. The report concluded the chances of such an accident were slim – statistically one chance in 10,000 in any given year of WIPP operations.
The “roof fall” scenario was viewed as even less likely. Freshly dug into the underground salt beds in which WIPP was built, the rooms’ roofs were supposed to remain stable and at low risk of falling in for a long period of time, according to the safety analysis. The statistical probability of such a roof fall incident was calculated at one chance in a million during a given year of WIPP operations.
Such an accident, according to the safety analysis, could leave a large number of waste drums crushed and leaking.
Department of Energy officials did not respond to repeated requests from the Journal for information about what contingency plans existed prior to the Valentine’s Day leak for cleaning up such a mess. But a contingency planning document developed jointly by WIPP and New Mexico Environment Department regulators, obtained by the Journal, suggests a complex effort to identify and either excavate or immobilize every detectable bit of contamination within the vast underground salt mine.
Steps to be taken could be as simple as vacuuming or using Windex to clean up contaminated surfaces, according to the plan, or as complicated as excavating entire sections of contaminated mine corridor walls and disposing of them as radioactive waste.
Cleaning up contamination on a solid, smooth surface is relatively straightforward, Neill said. But the mine’s walls, which are simply rock salt, could be a much bigger problem because of the risk of further spreading the contamination. “When you grind away a wall in the mine, you generate a hell of a lot of dust,” he said. “If it’s on a polished floor, it can be removed readily. If it’s on a sponge-like material, it’s a bear.”
In a statement in response to Journal questions, energy department spokeswoman Deb Gill said: “An integrated recovery strategy is being developed that will lead to the return of normal waste disposal operations.”
How long that might take remains unclear. In a formal legal notice, the New Mexico Environment Department said, “It is believed … that the WIPP will be unable to resume normal activities for a protracted period of time.”
A summary of the 1997 safety analysis can be found here.
Journal staff writer Lauren Villagran contributed to this report.