The K-Basins, a pair of underground White House-sized reinforced concrete structures built in the 1950s near the banks of the Columbia River, are among the worst contaminated sites at the Hanford Nuclear Reservation.
When the plutonium factory closed down operations in the 1970s and 1980s, the basins became the depository of convenience for the most hazardous reactor material: Thousands of spent uranium fuel rods bearing plutonium that was never harvested. The "infamous" K East Basin was removed in 2009 but the full extent of the groundwater and river contamination from its faulty fuel rod storage may never be fully known.
GlobalSecurity.Org paints a grim picture of the storage of spent nuclear fuel in the K-Basins. Here are excerpts from a GlobalSecurity report on the K-Basins before fuel rods were removed from the site at the turn of the century:
"Nearly 80 percent (2,100 metric tons) of the DOE's nationwide inventory of spent nuclear fuel is in the K Basins, located adjacent to the K East and K West Plutonium Production Reactors, which were shut down in 1970 and 1971. The function of the K Basins is the safe storage of irradiated reactor fuel until it can be disposed or transferred to a safer location. The fuel in the K West Basin is encapsulated; the fuel in K East Basin is not. ...
"The indoor basins ... were built in 1951 and designed for a 20-year life. They were not designed for long term storage of spent reactor fuel, and they do not meet commercial nuclear or DOE safety and quality standards. The rectangular, reinforced concrete basins are 125 feet long, 67 feet wide, 21 feet deep and are divided into three sections. Each basin holds almost 1.2 million gallons of water. Nominal water depth above the fuel is 16 feet. The water provides a radiation shield for facility workers. ...
"The fuel was not designed for long term storage. It was to be stored for a short period of time (a maximum of 180 days) before being transported to PUREX, dissolved, and reprocessed to extract uranium and plutonium. The K West basin was drained, cleaned, and given an epoxy coating before spent fuel from N Reactor was placed there. The 1,000 metric tons of fuel in the K West basin were encapsulated in leak-proof canisters. ...
"Of greater concern is the 1,100 metric tons of spent N Reactor fuel in the K East Basin. K East Basin was not refurbished, and the fuel in K East Basin is stored in open canisters. Some of the fuel has been stored at the K East Basin since 1975. Thousands of the spent fuel assemblies have broken cladding, allowing the basin water to reach the uranium metal fuel, which contains plutonium and highly radioactive fission products. Water corrodes the fuel, and the corrosion products are released into the basin water. Many corrosion products have been distributed around the K East Basin as sediment. Enough sediment has accumulated over the years to form a sludge on the basin floor.
"Between 1974 and 1979, an estimated 15 million gallons of contaminated water from K East Basin leaked into the soil through a construction joint in the discharge chute area of the basin. The construction joint was repaired in 1980. Another leak of about 50 gallons per hour occurred in February 1993. It continued for several months and leaked an estimated 94,000 gallons of water before it stopped on its own."
Last month, The Daily Beast reported a lengthy update on the cleanup effort at Hanford. Here's the status of the K-Basins, according to the Beast: "Crews spent a decade removing the 2,100 tons of as-yet-undissolved rods, and then three more years vacuuming 47 cubic yards of sludge out of the more damaged East Basin and dumping it in the less-damaged, and now retrofitted, West Basin. Today, the rods are sitting in a building at Hanford, awaiting vitrification and eventual storage at a national repository to be determined."
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