Nuclear Wastes
From Thermal-FluidsPedia
Uranium undergoes several changes as it is mined, processed, burned, reprocessed, and eventually discarded and stored in a repository. Along the way, uranium fuel leaves a footprint by producing and leaving behind various levels of radioactive waste. Depending on the amount and type, radioactive waste can be classified as low level, intermediate level, or high level. Low- level nuclear wastes are those with relatively short half-lives. They come from hospitals, medical and research laboratories, x-ray machines, and contaminated clothing and equipment. Many commercial products such as watches, ionization smoke detectors, eyeglasses, dental porcelain, luminescent products, instrument dials, signs, and markers contain some radioactive materials. Low-level wastes do not need any casks and are suitable for shallow depth burial or incineration.
The sources of intermediate-level nuclear waste are nuclear enrichment plants, nuclear weapons facilities, and contaminated parts of nuclear power plants before decommissioning. Intermediate-level wastes are usually solidified in concrete and, depending on their type, buried in shallow or deep underground repositories.
High-level nuclear wastes are spent fuel and other products from the reactor core and, if it has been decommissioned, the reactor itself. A typical power plant generates about 20-30 tons of high-level radioactive wastes each year, mainly cesium-137, strontium-190, and technetium-99. Plutonium-239 is the most serious byproduct of breeder reactors.
References
(1) Toossi Reza, "Energy and the Environment:Sources, technologies, and impacts", Verve Publishers, 2005