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Spent nuclear fuel, occasionally called used nuclear fuel, is nuclear fuel that has been irradiated in a nuclear reactor (usually at a nuclear power plant). It is no longer useful in sustaining a nuclear reaction in an ordinary thermal reactor and, depending on its point along the nuclear fuel cycle , it will have different isotopic ...
The Nuclear Waste Policy Act of 1982 established a timetable and procedure for constructing a permanent, underground repository for high-level radioactive waste by the mid-1990s, and provided for some temporary storage of waste, including spent fuel from 104 civilian nuclear reactors that produce about 19.4% of electricity there. [38]
Dry cask storage is a method of storing high-level radioactive waste, such as spent nuclear fuel that has already been cooled in a spent fuel pool for at least one year and often as much as ten years. [1] [2] Casks are typically steel cylinders that are either welded or bolted closed. The fuel rods inside are surrounded by inert gas. Ideally ...
Example of a spent fuel pool from the shut-down Caorso Nuclear Power Plant. This pool is not holding large amounts of material. Spent fuel pools (SFP) are storage pools (or "ponds" in the United Kingdom) for spent fuel from nuclear reactors. They are typically 40 or more feet (12 m) deep, with the bottom 14 feet (4.3 m) equipped with storage ...
High-level waste is the highly radioactive waste material resulting from the reprocessing of spent nuclear fuel, including liquid waste produced directly in reprocessing and any solid material derived from such liquid waste that contains fission products in sufficient concentrations; and other highly radioactive material that is determined, consistent with existing law, to require permanent ...
A 1000-megawatt nuclear power plant produces about 27 tonnes of spent nuclear fuel (unreprocessed) every year. [44] For comparison, the amount of ash produced by coal power plants in the United States is estimated at 130,000,000 t per year [ 45 ] and fly ash is estimated to release 100 times more radiation than an equivalent nuclear power plant.
Spent fuel consists of radioactive ceramic, cooled until its short-half-life radioactives have decayed, so its heat-production is negligible. When initially made, the ceramic fuel is also wrapped in sealed tubes of corrosion-resistant zirconium alloy. Therefore, spent fuel is not water-soluble in any conventional sense, and is mechanically sturdy.
The high short-term radioactivity of spent nuclear fuel is primarily from fission products with short half-life.The radioactivity in the fission product mixture is mostly due to short-lived isotopes such as 131 I and 140 Ba, after about four months 141 Ce, 95 Zr/ 95 Nb and 89 Sr constitute the largest contributors, while after about two or three years the largest share is taken by 144 Ce/ 144 ...