TABLE OF CONTENTS Radioactive waste is generated by the following activities:
medical uses (radiodiagnostics and radiotherapy) and industrial uses without nuclear reactors (radiography of mechanical components, irradiation of goods for disinfection/sterilization/ conservation);
operation and decommissioning of nuclear plants.
The waste is mainly classified according to its radioactivity level and to its decay time. These two characteristics principally influence the choice of the best method for waste treatment and its storage/ disposal.
A classification internationally used is shown in Table 23-1, together with the suggested management method.
| Category | Characteristic | Suggested management |
|---|---|---|
| VLLW (very low-level waste) | Waste which decays in a few months (maximum several years) to levels lower than the limits fixed for unconditional release. | Temporary storage and disposal as conventional waste. |
| LILW-SL (low- and intermediate-level waste short lived) | Low- and medium-activity waste with limited content of ?-emitting nuclides. | Conditioning and disposal in an engineered surface site. |
| LILW-LL (low- and intermediate-level waste long lived) | Low- and medium-activity waste which exceed the limit of 4000 Bq g for ?-emitting nuclides. | Conditioning in a concrete matrix and disposal in medium depth storage (>100 m). |
| HLW (high-level waste) | Waste which exceeds the limit of 4000 Bq g ?1 for ?-emitting nuclides and shows a significant production of heat (>100 W m ?3). | Conditioning in vitrified matrix and disposal in a deep geological formation (100 800 m) after a storage period of 30 50 years in adequate engineered structures. |
