NEAR RICHLAND, Wash. - A rare emergency on the Hanford site forced the evacuation of some areas and required some workers to exercise 'take cover' precautionary measures. It happened around 9:35 Wednesday night at the C Tank Farm. Crews were working to move some radioactive waste from a single shell to a double-shell tank.
The Department of Energy posted an alert on the www.Hanford.gov website saying it was an alert level emergency which is the lowest level. It's only called upon when "liquid waste leaks from a waste transfer system."
DOE said that about 80% of the waste was out of the tank when it happened with just a few inches of hard to reach waste at the bottom.
As the work was being done a routine survey of radioactive levels showed above normal levels. It is believed material may have leaked from either a hose in hose transfer line or a containment box. However, workers found no visible tank leaks.
Four workers who were working the C Tank Farm were sent to Kadlec Regional Medical Center. They were checked out and released back to work with no restrictions.
By 4:00 Thursday morning very low levels were still being detected at that spot but a sealant was used to stop any spread of contamination. By just after 5:00 a.m. the emergency alert was over.