The Nuclear Regulatory Commission issued a “white” safety finding to the Columbia Generating Station in Washington state after completing an evaluation of a waste shipping incident to US Ecology on leased land at the Hanford Site. Energy Northwest, operator of the nuclear power plant near the city of Richland, was notified of the decision on Thursday.
The NRC evaluates regulatory performance of commercial nuclear power plants on a color-coded scale of green, white, yellow, or red, with white indicating an incident of low to moderate safety significance. The Columbia Generating Station will be placed under increased oversight for at least six months until it shows improvements in shipping practices were effective.
In November, the plant shipped a cask of radioactive waste, including filters, from the plant to the US Ecology disposal site about 10 miles away, with much of the trip on Hanford land closed to the public. US Ecology accepts Class A, B, and C low-level radioactive waste from commercial and government customers in 11 western states.
The Energy Northwest cask held waste that was more radioactive than it was approved to haul because some contaminated items in the shipment had not been properly labeled or inventoried, in an issue dating to 2010. In addition, radiation survey results were improperly recorded as contact radiation rather than a measurement taken 6 inches away from the waste.
US Ecology rejected the shipment when it found radiation levels seven times higher than declared on the shipping manifest, according to Energy Northwest. The Washington state Department of Health subsequently suspended Energy Northwest’s radioactive disposal permit. The state gave conditional approval to resume shipments in April and restored full privileges in June.
