Following a partial tunnel collapse in May at Hanford’s Plutonium Uranium Extraction Plant, a facility unused since the 1980s, a report from DOE and its contractor for the area, CH2M Hill Plateau Remediation Co., says a second facility tunnel, which once processed chemicals needed in nuclear production, does not meet current standards. 

“We will work closely with [the Dept. of Ecology] to determine how best to stabilize Tunnel 2 and ensure the safe storage of the waste until it can be remediated,” says Doug Shoop, manager of the DOE Richland operations office.

According to the report, the 1960s design of Tunnel 2, about 1,700 ft long and built with metal and concrete, does not meet current codes for structural integrity and may not be able to bear the weight of the soil above it, placing the structure at “high potential for localized collapse.”

The tunnel contains 28 rail cars that hold waste from Hanford’s plutonium processing.

“We are evaluating options for using a remote capability to get a look at the general condition of the inside of the tunnel as well as to take radiological readings,” Shoop said. “We have increased our monitoring of the tunnels, including daily walk-downs and cameras that overlook both tunnels.”

A report detailing corrective actions is due on Aug. 1.