Hanford Site, Washington

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August 23, 2008, 3:35 am
180px-Early Hanford site.jpeg The Hanford site in the 1940s.

Hanford Site, Washington (46° 32' 11.00" N, 119° 31' 12.00" W), is a 1,518 square kilometer (586 square mile) tract of semi-arid land located within the Columbia River Basin in southeastern Washington, about 50 miles north of the Oregon border. The Columbia River flows through the Hanford Site boundary. In early 1943, the U.S. Army Corps of Engineers selected the Hanford Site as the location for nuclear reactor and chemical processing facilities for the production, separation, and purification of plutonium. The isolated 500,000-acre Hanford Site offered security for sensitive operations. Large quantities of electricity and cooling water (at least 25,000 gallons per minute) were available and a mild climate allowed year-round work. The Federal Government purchased the site, through eminent domain, and then evacuated the towns of White Bluffs and Hanford and all of the surrounding farmland to make room for the site.

Hanford was built from March 1943 to August 1945 at a cost of $230 million. The Army Corps of Engineers oversaw the entire project for the government and hired the DuPont Company for its expertise in large industrial operations to design, build, and operate the facilities. Hanford became was one of the manufacturing sites for uranium and plutonium used in producing atomic bombs for the Manhattan Project during World War II. The U.S. effort to create the atomic bomb was known as the Manhattan Project because it was run by an Army Corps of Engineers group who called themselves the Manhattan District. The plutonium manufactured at the Hanford Site was used to build the first nuclear bomb that was tested at Trinity Site, New Mexico, and used to build Fat Man, the bomb that was dropped on Nagasaki, Japan.

There were three water-cooled reactors built at the Hanford Site, spread apart by six miles along the southern bank of the Columbia River. The so-called B Reactor was the world's first plutonium production reactor, and was designed by Enrico Fermi and other scientists at the University of Chicago. The first experiments in the B-Reactor started on July 12, 1944, and it received its first fuel of mixed U-235 and U-238 on September 13, 1944. The process of plutonium production began on September 26, 1944, with the first plutonium actually produced on November 6, 1944.

The plutonium made at the Hanford Site was to be used in the Trinity bomb and the Nagasaki bomb which were employed during the war. Hanford’s plutonium production reactor was instrumental in creating atomic bombs. Without it, it would not have been possible to make more than one bomb by August 1945. As a result of the successful Manhattan Project, the nuclear weapons age was born.

For the next 45 years, Hanford’s primary mission was to continue to produce plutonium for use in nuclear weapons. During that time, Hanford went through several major expansions. Eventually, the government built nine nuclear production reactors, five chemical separation plants and dozens of support facilities. Plutonium production ended at Hanford in 1990. The U.S. Department of Energy (DOE) now manages the Hanford Site.

180px-Hanford waste.jpg Retrieval of improperly buried waste at the Hanford Site.

Today, Hanford is the site of the United States’ largest nuclear waste clean-up effort. Hanford is among the most contaminated sites in North America, holding more than 60 percent of the nation's highly radioactive and chemically hazardous wastes. In 1989, the U.S. Department of Energy and the U.S. Environmental Protection Agency signed a legally-binding agreement to build a Waste Treatment Plant to convert the nuclear waste and hazardous waste into leak-proof glass logs for safe, permanent storage.

At the onset of clean-up, the site contained 177 single- and double-shelled tanks with 53 million gallons of high-level radioactive waste, equivalent to 2,650 rail cars full of waste. Much of the waste sits in obsolete, leak-prone tanks that are decades past their design life. In all, more than 1,900 individual waste sites have been identified at Hanford.

This radioactive waste poses a serious threat to the land, the nearby Columbia River, human health, and the region's economy. Sixty-seven of the single-shell tanks have leaked about 1 million gallons of highly radioactive waste into the ground. This waste is traveling through groundwater toward the Columbia River. Groundwater under two of the tank farms is contaminated with Technetium-99 at amounts several hundred times greater than the federal drinking water standard. Groundwater under a third tank farm contains uranium concentrations at amounts 20 times higher than the federal drinking water standard. With the exception of the above tank farms, most of the contamination is currently still in the soil above the groundwater, but is moving downward toward the groundwater.

Current plans are to retrieve the waste from the tanks - including the sludge - and separate it into two waste streams. One waste stream will contain the majority of the radioactivity, the other will contain much smaller amounts of radioactivity. After separation, the high-activity waste stream will then go through vitrification - a process that mixes the radioactive wastes with molten glass. The mixture is poured into stainless steel containers where it will harden into a solid, glass form. The canisters of high-level radioactive waste will be stored indefinitely at Hanford. The low-activity waste - which will make up the majority of Hanford’s waste - will be buried on site. The vitrification facilities are scheduled to start up by 2009 and be fully operational in 2011. It may take 20 to 30 years to then vitrify all of the waste.

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Citation

Lowitz, M. (2008). Hanford Site, Washington. Retrieved from http://editors.eol.org/eoearth/wiki/Hanford_Site,_Washington