On October 24, 1995, at Hanford, the manager of the Plutonium Finishing Plant manager suspended all operations controlled by radiation work permits except for surveillances by radiological control technicians, hands-off visual inspections, and tours. Exceptions to the suspension order must be approved by senior plant managers. The plant manager acted because technicians and operators demonstrated poor contamination control practices in three events. Radiological operations will remain suspended until senior managers can review radiological conduct of operations and implement corrective actions. (ORPS Report RL--WHC-PFP-1995-0057)
On May 30, 1995, radiological control technicians detected alpha contamination on the shoes of seven operators and technicians in a change area. The highest alpha contamination was approximately 1500 dpm. The contamination occurred while they were transporting and surveying five bags of low-level waste from a scrubber cell. The occurrence report stated that the event was caused by inadequate control of contamination resulting in its spread to a radioactive materials area. (ORPS Report RL--WHC-PFP-1995-0026)
On September 19, 1995, two operators were contaminated when they placed a radioactive waste package in a waste drum. The package contained a heat exchanger wrapped with three 10-millimeter plastic bags. A radiological control technician detected alpha contamination of 2,100 to 14,000 dpm on the gloves and arms of one operator and alpha contamination of 1,000 to 4,100 dpm on the arms of the second operator. The occurrence report stated that the contamination came from the plastic bags, which were probably breached by the weight of the heat exchanger as it lay on the floor or during handling. (ORPS Report RL--WHC-PFP-1995-0050)
On October 23, 1995, a supervisor briefed a work crew before they handled radiological waste. Because the job involved transporting heavy waste wrapped in 10-millimeter plastic bags, the briefing included verbal instructions and lessons learned from the May 30 and September 19 events. Despite these instructions, three operators failed to adhere to the guidance of the pre-job briefing and contaminated their shoes with approximately 10,000 dpm alpha radiation. Also, one of the operators discovered skin contamination on his left forearm. Radiological control technicians took nasal smears from individuals involved in the event and confirmed four positive nasal smears with the highest reading 115 dpm alpha radiation. The four individuals repeatedly blew their noses until technicians could no longer detect contamination. (ORPS Report RL--WHC-PFP-1995-0055)
Contamination events related to waste-handling have continued despite efforts by managers to develop and disseminate lessons learned prompting the plant manager to suspend radiological operations pending completion of the radiological operations review. NFS will provide additional information on the causes and lessons learned from this event as appropriate in a future Weekly Summary.