Watchdog group Hanford Challenge is calling for an independent look at the threats that Hanford’s contamination may pose to nearby communities after a small, newly completed study reported radioactive contamination in the personal cars or trucks of three workers at the Energy Department site in Washington. The study said the cars had previously been checked for contamination at Hanford and released to workers.
“Multiple lines of evidence indicate that modest but detectable level(s) of alpha-emitting nuclides were collected on the air filters of vehicles belonging to Hanford workers,” according to the study conducted by Marco Kaltofen of Boston Chemical Data Corp. “These vehicles had been cleared and released from radiation protection zones at the Plutonium Finishing Plant.”
Hanford Challenge found 29 Hanford workers who volunteered to have their vehicles’ air filters checked for contamination. In addition, dust samples were collected by wiping surfaces on another car. Kaltofen collected the dust from air filters and sent samples from the filters and the additional wipe samples from the 30th car to a licensed commercial radiological testing laboratory.
Kaltofen said that dust from three of the vehicles tested positive for alpha-radiation contamination. Further testing confirmed the presence of americium, uranium and thorium in the positive samples, he said.
“Given the small sample size in this study, it is assumed the full potential for radioactive particulate matter in these release vehicles has not been explored,” said the conclusion of the study, which was released Tuesday. Kaltofen recommended a broader independent look at residual contamination in the communities around Hanford and an assessment of health risks, and Hanford Challenge agreed.
All demolition work, other than the load out of some already packaged waste, has been stopped at the Plutonium Finishing Plant since mid-December. A spread of airborne radioactive contamination was discovered then after the completion of most of the demolition of the plant’s most contaminated facility, the Plutonium Reclamation Facility.
Bioassays found 42 workers had inhaled or ingested radioactive contamination both in the December incident and an earlier airborne spread of contamination at the plant in June 2017. Surveys of worker vehicles that had been parked at the plant just before the December spread was detected, found seven with radioactive particles on their exteriors. Some had been driven off site before the contamination was discovered. They were decontaminated and released to workers.
