Citing a "lack of sustained improvement" in safety operations, the federal Department of Energy has fined a Hanford, Wash., contractor $316,250 for violations of nuclear rules that exposed workers to radiation.

The fine reflects increased federal scrutiny of CH2M Hill Hanford Group, which manages the storage of highly radioactive and chemical wastes in 177 tanks at the Eastern Washington nuclear complex undergoing a multibillion-dollar cleanup effort.

"These issues have been identified before and attempts at corrective action have not been effective," said John Shaw, an assistant energy secretary for environment, safety and health.

The Hanford work is exempt from oversight by OSHA. Instead, Hanford safety is monitored by the Department of Energy, which also is charged with carrying out the cleanup.

Department officials, in announcing the fine this week, noted four separate exposure events. Those events included the June 2003 contamination of several workers while removing equipment from a valve pipe and the July 2004 radiation exposure of a worker while removing equipment from a tank.

In all the cases, no worker's radiation dose exceeded regulatory limits. But investigators found "multiple incidents" where the contractor failed to comply with established operating procedures. And, because of a lack of controls, the radiation exposures could have been much higher.

Since last summer, CH2M Hill has improved training and accountability and taken other steps to address the Department of Energy concerns, according to a company statement released yesterday.