Six workers reported smelling a suspicious odor Wednesday outside the U waste storage tank farm at the Hanford Site in Washington state, bringing the number of workers reporting possible chemical vapors so far this year to 20. However, just five have requested medical evaluations.
That number is down significantly from the more than 50 workers who received medical evaluations from spring through mid-summer in 2016, just before workers were required to wear supplied air respirators for most work in Hanford’s tank farms.
The six workers, who all declined medical evaluations, were performing maintenance on electrical distribution equipment and were not required to be wearing supplied air respirators because they were outside the tank farm fence line. None reported symptoms typical for chemical vapor exposure, such as headaches, coughing, nose bleeds, or a metallic taste in the mouth. Workers were cleared out and industrial hygiene technicians gathered air samples, but no monitoring in the area or samples showed chemicals at levels of concern.
Hanford stored 56 million gallons of radioactive and chemical waste in underground tanks. The waste, which will eventually be treated for disposal, is the byproduct of the site’s former mission to produce plutonium for the U.S. nuclear deterrent.
Workers this year have reported suspicious odors twice in February, twice in June, once in September, and twice earlier this month. Hanford policy is to evacuate areas and collect air samples if workers smell an unidentified odor that might be from chemical vapors associated with waste stored in underground tanks.
Tank farm contractor Washington River Protection Solutions has been working on ways to better protect workers, including testing a system that uses heat to destroy chemical vapors and a system that would expel vapors at high speeds far above the ground. Continued testing is required by a settlement agreement reached last month in a federal lawsuit over worker safety brought by the state of Washington, the watchdog group Hanford Challenge, and a local union against DOE and its tank farm contractor.
