RICHLAND, Wash. – EM’s Office of River Protection (ORP) and tank farms contractor Washington River Protection Solutions (WRPS) began retrieving waste from underground double-shell tank AY-102 this month, ahead of schedule, meeting requirements of a settlement agreement with the State of Washington.
AY-102 contained about 749,000 gallons of mixed radioactive and chemical waste. About 550,000 gallons of the tank’s liquid waste — called supernate — has been retrieved and transferred to double-shell tank AW-105 as of March 9.
Prior to retrieval, AY-102 contained about 594,000 gallons of supernate, and 151,000 gallons of sludge. Sludge retrieval will start using two sluicing nozzles, which spray liquid to break up the sludge so it can be pumped to double-shell tank AP-102.
AY-102 is located in the AY Farm and has a capacity of approximately 1 million gallons. It was the first of 28 double-shell tanks constructed at Hanford, and was declared operational in 1971.
In 2012, a small amount of waste was discovered leaking from the primary shell into the annulus, the space between the inner and outer shells. An estimated 50 to 70 gallons of waste has leaked into the annulus. Extensive monitoring shows no indication any waste has leaked to the environment.
In September 2014, ORP and WRPS signed the agreement with the state, creating a path forward to remove the waste from AY-102. The agreement requires DOE to complete waste retrieval no later than March 4, 2017.