There are 64 metric tons of plutonium at the Hanford site, and 50 million gallons are highly radioactive. Hazardous chemical waste is housed in 177 underground storage tanks (USTs). 67 of these USTs are known/suspected to be leak. There are also 2100 metric tons of spent nuclear fuel in storage basins near the Columbia River. Beneath the site lies 270 billion gallons of contaminated groundwater. There are also 1900 capsules of radioactive strontium and cesium being stored at the Hanford site, totaling 37% radioactivity.
Beneath the surface of the Hanford site lies 790,000 cubic meters of solid waste at a total of 1700 waste sites. There are also 500 contaminated facilities that must be removed, and 4 metric tons of plutonium.
Much progress has been made in the cleanup of the Hanford Nuclear Site. First, they started to resolve the UST issues and tank safety, which involves removing all Hanford tanks from the congressional watch list. They are also removing pump-able liquids from 131 shell tanks. Another priority is deactivating the nuclear chemical processing plants and moving half of the nuclear waste from the underground storage pools to a safe, dry storage on site. They are packaging plutonium solutions and residues to be shipped offsite for disposal. They're actively dealing with the groundwater plume and dismantling reactor complexes so they can be removed. Two reactor cores are being cocooned for storage and they're working on 3 more. They're moving 4 million tons of contaminated material away from the Columbia River shoreline (40% total).
The original clean up plan cost too much and took too long, so the Department of Energy (DOE) developed a plan to reduce risk and clean up by 2035:
The biggest risk is the 4 tons of plutonium in various forms. This will be appropriately packaged for use and storage by 2004. Vent ducts were to be cleaned by 2006. In addition to plutonium, there is also strontium and cesium stored in capsules on site, which contain 130 curies of radioactivity. These capsules are stored in water, and are going to be moved to dry storage for more protection. The DOE plans on accelerating waste disposal of 40,000 drums equivalent to low level waste and some amount of "true" waste. This buried waste was to be removed by 2010, which is accelerated by 4 years from the original schedule. DOE also plans to accelerate 15,000 drums of suspect transuranic waste. There are many buildings on site that are being scheduled in groups to accelerate cleanup. The buildings threatening groundwater are the highest priority. There is also an uplant regional closure plan, which encompasses the final disposition of the uplant canyon facility and smaller buildings around the plant and remediation of nearly waste sites. This will serve as a template of other large Hanford facilities. The cleanup of the Hanford Nuclear Site is very complex, expensive, and intense. It will create many jobs in the future, and give us clean up experience for future problems and help us identify new technologies. It will also teach us how to design safer nuclear facilities and reduce risk of exposure to hazardous chemicals.
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