Two workers at the Hanford Site in Washington state on Friday received medical evaluations after one smelled a suspicious odor and developed symptoms consistent with possible exposure to chemical vapors from radioactive tank waste, according to tank farm contractor Washington River Protection Solutions (WRPS). The second worker had no symptoms but requested a medical check as a precaution. Both were cleared to return to work after the evaluation.
The incident occurred while the workers were in the airlock of the 242-A Evaporator pump storage room, performing work related to valves for the planned startup of an evaporation campaign at the facility to reduce the liquid waste in double-shell tanks. Because the 242-A Evaporator is not in a tank farm at the Energy Department cleanup site, the workers were not required to wear supplied-air respirators as protection against vapors associated with waste stored in underground tanks.
The area was cleared of workers, and WRPS industrial hygiene technicians checked for chemical vapors. When they found no evidence of chemicals above background levels, access to the area was restored, according to WRPS. The evaporator campaign remains on schedule to start as soon as June 22 and continue for a couple weeks, the company said.
On Feb. 6, two workers reported a suspicious odor outside the SY Tank Farm. A day earlier five workers reported a suspicious odor 7 miles away inside the 702-AZ exhauster building, where supplied-air respirators are not required. All declined medical evaluations.
The Hanford Site stores 56 million gallons of radioactive and chemical waste in underground tanks, a legacy of the site’s history as a plutonium production complex for the U.S. nuclear deterrent. Exposure to vapors from the waste has been a long-term concern: DOE is now trying to settle a lawsuit filed by Washington state and other plaintiffs demanding increased worker safety.
