Low-level waste management at nuclear electric power stations

Nuclear Electric generates around 1,800 m3/y of solid low-level waste (LLW) from its 26 reactors in the UK. A review of waste management practices has led to improved methods for sorting, volume reducing and assaying LLW to demonstrate compliance with legislation and to reduce costs. A description of waste sorting and streaming is presented together with a discussion of volume reduction using low- and high-force compaction and incineration, including burning waste oil. Details are presented of a new LLW assay system which uses high resolution gamma spectrometry and accounts for waste matrix self-shielding corrections by different attenuation of multi-peaked isotopes within the waste itself. The system, which has been extensively and systematically validated, improves accuracy and reduces the tendency of previously used techniques to overestimate disposal activity. Equipment to implement these various improvements is currently being installed at most NE sites