Spent Fuel
Spent fuel is nuclear fuel that has been irradiated in a nuclear reactor, typically in a nuclear power plant for electricity generation. It is called “spent” because it is no longer useful in the same reactor, though it retains significant radioactivity and heat.
Composition & Hazards
- Fission Products: Highly radioactive isotopes (e.g., Cesium-137, Strontium-90) with short-to-medium half-lives.
- Transuranics: Long-lived actinides (e.g., Plutonium-239, Americium) that pose long-term radiotoxicity.
- Heat Generation: Requires active cooling or passive decay heat removal for years/decades.
Management & Disposal
- Temporary Storage: Cooling pools followed by dry cask storage on-site.
- Reprocessing: Chemical separation of usable uranium/plutonium from fission products (PUREX process).
- Final Disposal: Deep geological repositories (e.g., Onkalo, Waste Isolation Pilot Plant).
Environmental & Historical Context
- Accidents & Losses: Spent fuel or intact cores can be lost during maritime incidents, posing long-term contamination risks.
- See: Cold War’s Sunken Nuclear Subs: Environmental Risks, Monitoring, and Salvage for details on ~150 lost subs and salvage challenges.
- Legacy Waste: Cold War-era naval reactors require specialized monitoring due to corrosion risks and depth-related salvage difficulties.
Related Concepts
- Nuclear Fission
- Radioactive Waste
- Geological Repository
- Nuclear Submarine