The Nuclear Regulatory Commission is investigating an incident in which a recent low-level radioactive waste shipment from the Columbia Generating Station in Washington state to a nearby disposal facility was rejected due to under-reported radiation levels.
The NRC said Monday that workers at the nuclear power plant on Nov. 9 shipped a single package of contaminated filters to a U.S. Ecology disposal facility 10 miles away. The disposal facility found that radiation levels for the package were more than seven times higher than documented in the shipping manifest. The package was sent back to the plant, where it is now stored. Energy Northwest operates the facility, which is located 10 miles north of Richland, Wash.
The Washington state Department of Health then suspended Energy Northwest’s disposal permit privileges for shipments to U.S. Ecology until a written plan with corrective actions for the plant is approved and a state inspection at the site is finished.
Company spokesman Michael Paoli said the radiation level for this shipment was measured at 90 rem an hour inside a 45,000-pound, heavily shielded cask. The filters are used for vacuuming and cleaning the plant’s spent fuel pool, which the company does every six years. Entergy Northwest ships the filters to U.S. Ecology every six-year cycle, while also processing one or two separate waste shipments a month. Paoli said by email that the company anticipates having disposal privileges reinstated by mid-January, as it’s a one- or two-week process that might be delayed around the holidays.
A three-member team of inspectors from the NRC is expected to spend a week at the site evaluating the licensee’s cause analysis and the adequacy of corrective actions, according to an NRC press release. An inspection report is expected within 45 days of the end of the inspection.
“The purpose of the NRC’s special inspection is to better understand the circumstances surrounding this event, which revealed weaknesses in the licensee’s process for packaging and preparing radioactive waste shipments,” NRC Region IV Administrator Kriss Kennedy said in a statement. “While there was no undue risk to the public, had a transportation accident occurred, there was a potential that members of the public could have been exposed to radiation levels in excess of NRC regulatory limits.”
