More than 56,000,000 gallons of chemical and nuclear waste is stored in 177 underground storage tanks at the Hanford Site. Ultimately, these wastes will be removed from the tanks and transferred to the Waste Treatment Plant at Hanford where the waste will be turned into a glass-like, stable substance through a process called vitrification.
However, removing the waste from these underground storage tanks isn’t easy. The tanks were built decades ago and they weren’t designed to allow workers to easily access the materials inside. Pumps, ventilation systems, and monitoring equipment were installed in the tanks, but the only way that crews can get at the waste itself is by lowering equipment through pipes extending out of the various tanks. Adding to the challenge is the fact that these risers can be as small as four inches in diameter; the waste itself is extremely caustic and hazardous; some of the waste is in a semi-solid state; and the waste may be located in quadrants of the tank that are hard to get at.
Hanford crews designed and built the innovative Cold Test Facility (CTF) to develop ways to remove the waste from the tanks, without having to subject the workers or the equipment to the radioactive environment found in the tanks on the Site. The Cold Test Facility is a full-scale mockup of a single shell storage tank at Hanford, with the height, weight, and riser dimensions exactly the same as they are found on the Site. Workers can simulate the kinds of conditions that would be found inside a tank, while also testing new equipment and technologies which they believe could help remove tank waste that is in difficult-to-reach places or in a semi-solid state.
Using the CTF eliminates the trial and error method of removing tank waste at a considerable cost savings. If equipment designed to remove tank waste isn’t successful during testing at the Cold Test Facility, then it won’t be put into service at a tank at Hanford. By the same token, if a product is developed that works in the testing environment at CTF, it will continue to be evaluated for possible use in the real tanks at the Site.
Several new technologies have been designed, developed, and tested successfully at the Cold Test Facility, and have then been utilized in removing tank waste at Hanford. With many tanks to be emptied on the Site, the CTF is expected to continue to provide crews with the opportunity to test new ways to safely remove the waste in the years to come.