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Retrieval of Ninth Single-Shell Tank Complete

September 6, 2012 - 12:00pm


Richland - Washington River Protection Solutions (WRPS) has completed the retrieval of radioactive and chemical waste from single-shell tank (SST) C-104, an underground storage tank that once held 259,000 gallons of waste left over from nuclear weapons production at Hanford. WRPS is the tank operations contractor for the U.S. Department of Energy (DOE) Office of River Protection (ORP).

Tank C-104 is a 530,000-gallon-capacity SST that once contained the second-highest waste volume of the 16 SSTs in Hanford’s C Farm, including a significant amount of plutonium and uranium.

“We are committed to meeting our regulatory requirements,” said Joanne Grindstaff, Federal Project Director for Single-Shell Tank Retrieval and Closure. “This retrieval effort reduces the risk posed by the waste stored in this underground tank and gets us one step closer to retrieving all the tanks in C Farm by September 2014.”

Workers have now removed more than 99.5 percent of the waste from C-104. Operators used modified sluicing to remove the majority of the waste. This past spring, crews began a chemical soak process by adding sodium hydroxide to the tank to break down and soften the stubborn, stuck-on material at the bottom of the tank. Once the reaction was complete, crews completed a final water rinse of the tank.

“The successful completion of retrieving this tank is a reflection of the dedicated workforce at ORP and WRPS,” said Tom Fletcher, Assistant Manager for the Tank Farms Project. “There was a substantial effort from the workers to plan, prepare and retrieve this radioactive waste. All of this was done safely, even while work activities in the farm have been increasing.”

Despite these challenges, crews were able to complete the project more than eight months ahead of schedule and nearly $3 million under budget.

“C-104 retrieval certainly presented significant challenges,” said Kent Smith, WRPS Single-Shell Tank Retrieval and Closure Manager. “But the team was able to complete retrieval well below the volumetric goal established by the state—safely, months ahead of schedule and millions under budget.”

By the end of October, two additional tanks in C Farm are scheduled to be completed—C-107 and C-109.

WRPS is the DOE ORP prime contractor responsible for eliminating the risk to the environment posed by Hanford’s 56 million gallons of high-level radioactive and chemical waste stored in 177 underground tanks. These aging tanks are just a few miles from the Columbia River. ORP is responsible for safely retrieving and treating Hanford’s tank waste and closing the tank farms to protect the Columbia River. WRPS is owned by URS Corporation and Energy Solutions, with AREVA as its primary subcontractor.