Radioactive Waste Management
During the INPP decommissioning and dismantling process, it is important to ensure the safety of the environment, humans and employees. For this reason, the major decommissioning objectives are:
- retrieval of radioactive and non-radioactive materials (drainage of pipelines, oil removal from oil supply systems, etc.)
- safe radioactive waste management;
- ensuring of radiation control and safety in order to prevent radiation, chemical and other effects to humans and environment.
The main stages of radioactive waste management are possible depending on the type of radioactive waste (RW) - pretreatment, treatment, conditioning and packaging, storage and disposal. The main stages of RW management from its generation to disposal are presented in Figure 1 in reference to the objectives and operations of these stages.
- Pretreatment is the initial RW management stage during which the waste is sorted into the unconditional free release waste, waste requiring specific treatment, near-surface repository or deep geological disposal.
- RW treatment is to increase the security or economy by changing characteristics of the waste. For example, pressing and combustion are the ways of waste treatment.
- RW conditioning and packaging - actions during which the waste is transformed into the thermally and chemically steady form which retains stable during the transportation, storage and disposal. Conversion of waste into solid form, i.e. immobilization, is performed via the solidification, incorporation into a matrix and hermetic forms.
- Disposal – the last stage of waste management when waste is localized in a special storage facility ensuring necessary security – repository. Disposal should have isolation system of several barriers, i.e. installation of natural and engineered barriers that confine RW in order to prevent radionuclides from spreading into the environment.
- The access of RW to the following stages depends on the waste type which is determined by performing physical, chemical and radiation features characterization.
- As a result some RW can be free released or reused; also, waste is divided into groups in order to ensure the treatment techniques compliance with storage and disposal requirements.