Columbia Generating Station
Managing Nuclear Waste
All industrial processes have byproducts, called waste. Although nuclear power plants produce far smaller volumes of waste than most industries, some of Columbia Generating Station's wastes are radioactive and require special handling.
Much nuclear waste is ordinary trash, tools, protective clothing, wiping cloths, and disposable items that have been contaminated with small amounts of radioactive dust or particles. These items are classified as low level waste and are shipped to a licensed disposal facility located at Hanford.
Another waste product is used nuclear fuel, or spent fuel. The fuel consists of uranium dioxide encased in a solid ceramic material to form pellets, which in turn are sealed inside of long metal rods as part of a fuel assembly. Each fuel assembly spends approximately 5 years in the reactor core, after which it is considered "spent."
In Europe, where nuclear energy is widely used, spent fuel assemblies are recycled into new fuel; this greatly reduces the volume of high level waste that must be stored for the long term. In the United States, however, nuclear power plants are not allowed to recycle spent fuel so it must be stored.
Eventually, spent fuel will be shipped to a national disposal facility being developed by the U.S. Department of Energy at Yucca Mountain, Nevada. In the meantime, Columbia Generating Station will continue to safely store its spent fuel here on site.
Most spent fuel is stored in a specially designed pool of water inside the reactor building. The water cools the fuel and acts as a shield against radiation. Columbia Generating Station has also installed an additional dry cask storage facility on site.
The Independent Spent Fuel Storage Installation (ISFSI) holds spent fuel in an advanced system of steel and concrete casks. These casks are air-cooled and require no moving parts and no electricity to function; they are simple, safe and reliable. Each cask is carefully loaded and transported to a specially designed area on site, where it is stored and monitored until the national repository is complete.