An independent analysis has uncovered trace amounts of plutonium in an air sensor a half mile from the Waste Isolation Pilot Plant in southeastern New Mexico — the first time plutonium is believed to have leaked outside from within the facility.
It also was the highest levels of plutonium ever detected near the nuclear waste storage facility in its 15 years of operation, according to Russell Hardy, director of the Carlsbad Environmental Monitoring and Research Center.
“It’s still below what EPA considers actionable levels, but it’s important to know that some material did get out of the facility,” Hardy said.
A WIPP air monitor detected airborne radiation underground on Friday just before midnight, setting off an alert. WIPP reported the next day that its ventilation system had immediately switched to filtration mode, minimizing any potential release of radiation.
Plutonium and americium are cancer-causing when inhaled or consumed, Hardy said. The levels detected by CEMRC are below those considered unsafe by the Environmental Protection Agency.
WIPP said in a statement Wednesday that its filters remove at least 99.97 percent of contaminants from the air, “meaning a minute amount still can pass through.” WIPP previously said that there is no danger to human health.
CEMRC pulled its air sampling station filter on Sunday for testing. The center found 0.092 Becquerels (bcq), a measure of radioactivity, of plutonium and 0.64 bcq of americium on the air filter stationed about half a mile from the WIPP facility, well above the highest levels of those radioactive elements previously detected near WIPP.
CEMRC, a division of the College of Engineering at New Mexico State University, has detected plutonium and americium particles on four other occasions, Hardy said, all attributed to trace amounts of plutonium likely stirred up by heavy winds from sources outside WIPP. The highest level previously tested was 0.004 bcq of plutonium and 0.0005 bcq of americium.
“There is a lot more that needs to be known,” said Don Hancock, director of the Nuclear Waste Safety Program at the Southwest Research and Information Center in Albuquerque. “The big problem is, does anybody really know what happened in the underground and how much was released or is continuing to be released? And therefore how much is being captured by the filters and how much is getting into the environment?”
WIPP said Wednesday that it is developing a plan to safely re-enter the underground facility. Radiological professionals from other Energy Department locations and national laboratories are also assisting in the recovery, WIPP said.
The radiation alert comes in the wake of a different emergency that shut down the facility earlier this month, in which a truck used to haul salt caught fire underground. No workers were hurt, and the fire did not occur near the waste container storage areas.
WIPP halted shipments to the facility after the fire. No waste shipments to WIPP were scheduled for Feb. 14 through March 10 due to an annual maintenance outage, WIPP said, and shipments remain suspended.
WIPP stores radioactive leftovers of nuclear weapons research and testing from the country’s past defense activities — such as gloves and boots — in sprawling underground salt mines. The salt is excavated and waste is stored below ground in sealed containers. It is the first and only disposal facility of its kind.
A second CEMRC air sensor about 12 miles from the facility detected no radioactive particles. Hardy said CEMRC is in the process of testing 10 additional filters from an exhaust shaft at WIPP.