Types of radioactive waste classes at Nesca

High-level waste (HLW)

High-level waste is heat-generating waste (typically above 2 kW/m3 or waste that needs to be managed in terms of its heat-generating properties over long durations) with high long — and short-lived radionuclide concentrations which include fission products and actinides. SF pellets and element sections from post-irradiation testing of pressurized water reactor (PWR) fuel, waste from Mo production and SF from the SAFARI reactor are retained waste that is regarded as potential HLW. Potential HLW is retained in the facilities of origin or stored in interim storage facilities in accordance with facility-specific nuclear authorizations. Potential HLW with proven heat — generation capacity of less than 2 kW/m3 or waste that does not need to be managed in terms of its heat-generating properties may be considered for re-classification as ILW. Waste types with long-lived radionuclide concentra­tion levels that would result in an inherent intrusion dose of more than 100 mSv/a, after an institutional control period of 300 years, shall be managed as HLW.

HLW that is removed from authorized containment systems shall be processed to ensure a solid waste form in a waste package that is suitable for handling, transport and storage for a period of 100 years. Disposal of HLW is limited to a high degree of containment and isolation from the biosphere over long time periods, which is obtainable by regulated deep geological disposal (hundreds of metres).