Reducing the risk to the environment posed by radioactive and chemical waste in Hanford’s aging underground storage tanks poses one of the most complex cleanup challenges in the Department of Energy complex. Hanford’s tank waste includes materials from years of World War II and post-war weapons productions. These aging tanks are approximately 10 miles from the Columbia River and within a 50-mile radius of more than 200,000 residents.
When the cleanup of Hanford began in 1989, technologies were pioneered at Hanford to remove waste from the tanks and the development of new techniques and technologies continues today as Washington River Protection Solutions improves its understanding of the waste.
There are 149 aging single-shell tanks, more than 60 of which have leaked as much as 1 million gallons to the surrounding soil. Most of the pumpable liquids have been removed from the aging single-shell tanks and transferred to Hanford’s 28 newer and safer double-shell tanks, leaving behind mostly dry saltcake and mud-like sludge.
The nature of the waste and the environment inside the tanks defy conventional approaches. Because the tanks are buried underground and the waste inside poses a health risk, all work inside the tanks be performed remotely. In addition, the variety of waste forms still in the tanks requires a variety of tools to remove them. No single tool is adequate to remove the waste to a level that meets Tri-Party Agreement requirements. WRPS has extensive experience working under such constraints and is applying technological innovation combined with ingenious engineering to safely and successfully complete this hazardous and complex task.