Workers at the US Hanford site near Richland, Washington, have installed the last piece of pipe, connecting underground tanks storing radioactive waste and the waste treatment plant that will begin solidifying it in glass later this year. Bechtel National is designing, constructing and commissioning at Hanford the world’s largest radioactive-waste treatment plant.
The plant will use vitrification technology, which involves mixing the waste with glass-forming materials and heating it to 2,100 degrees Fahrenheit inside large melters. This mixture will then be poured into stainless steel canisters to cool and solidify. In this glass form, the waste will be stable and impervious to the environment, and its radioactivity will safely dissipate over hundreds to thousands of years.
Hanford is home to 177 underground waste storage tanks – a legacy of nuclear weapons development and nuclear energy research during World War II and Cold War. These include 149 single-shell tanks and 28 double-shell tanks, ranging from 55,000 to 1.265m gallons in capacity. The tanks, some of which are reportedly leaking, hold 56m gallons of waste.
Workers previously installed a 3,500-foot underground transfer line between the Waste Treatment and Immobilisation Plant and a million-gallon storage tank called AP-106. The tank holds about 830,000 gallons of waste that has been treated and is ready to send to the vitrification plant.
“Advancing the tank waste mission safely and effectively is a top priority for the Hanford Site,” said Brian Harkins, Acting Manager of the Department of Energy’s Hanford Field Office. “This last link brings Hanford another step closer to solidifying tank waste in glass. We’re doing some final testing at the plant to make sure the exhaust system is ready, and soon we’ll be ready to begin making glass.”
Carol Johnson, Hanford Tank Waste Operations & Closure (H2C) President and Programme Manager, noted: “Installing this last piece of equipment involved months of coordination with treatment plant staff for awareness and safety,” said “This final connection is a clear indication of the progress the One Hanford team is making toward hot commissioning.”
Hanford is currently “cold commissioning” the plant using a simulated waste made up of chemicals to test treatment and exhaust systems. “Hot commissioning” using waste from Tank AP-106 will begin later this year. Workers with H2C and the treatment plant are practicing waste transfer procedures to ensure safe, compliant transfers in the coming months.
The Department of Energy (DOE) is engaged in one of the great public works of this century at
The DOE Hanford Field Office is responsible for the safe and efficient retrieval, treatment and disposal of the chemical and radioactive waste stored in Hanford’s underground tanks. The mission includes building and commissioning the world’s largest radioactive waste treatment plant, which will immobilise the legacy tank waste through vitrification.
The DOE Hanford Field Office is also responsible for all remaining Hanford clean-up and is currently focused on stabilising and demolishing former plutonium production structures, excavating and disposing of contaminated soil and waste, treating contaminated groundwater, and configuring Hanford Site infrastructure for the future, with an emphasis on supporting the tank waste mission.
