Waste treatment after a radiological accident Miliza Malmelin

Starting points and scope of the work  After a radiological accident the area has to be cleaned and waste is generated.  The generated waste contains small amounts of radioactive substances which has to be taken into account during waste treatment.  The amounts of waste generated might be huge.  Most preparedness plans cover only the early phase of radiological accidents - the later phase (clean-up) is seldom covered  The scope: How should waste treatment be organized after a radiological accident.

What does the study cover?  Background: – Legislation applied – Authorities and their responsibilities  Waste generation: where, what and how much  General principles of waste treatment: what can be done to different types of waste  Waste treatment in practice: what would be done  Recommendations

The type of accident will affect the amount of waste and the type of waste generated (1/2)  Regionally large accident – most of the area will be lightly contaminated : no population protection actions, waste is generated when foodstuff and other products are thrown away, and when the environment is cleaned – Serious nuclear power plant accident – Nuclear weapon explosion  Local accident – will be limited to the nearby environment or indoors; waste is generated when the environment is cleaned and products are thrown away – Accident during transport or use of powerful source of radioactive radiation – Transport and storage of nuclear fuel – Illegal use of radioactive substances for deliberate contamination

The type of accident will affect the amount of waste and the type of waste generated (2/2)  The consistency and amount of radioactive substances – The characteristics of radioactive substances vary a lot – The intensity of the contamination will affect actions needed and what type and amounts of waste are generated  Accident area and time – The regional structure: production, business and other activities – The environment – Time of the year

Cleaning actions should be planned  Cleaning actions should be planned and made based on knowledge about the contamination (area, type and amount)  This way the amount and type of waste generated from cleaning actions can be predicted  The amount of waste generated is affected by the type of accident, the structure of the area, the cleaning actions chosen, the efficiency of decontamination wanted, the availability of cleaning equipment and personnel  The amounts of waste can be extremly large, so – the waste should be sorted according to type of waste and radioactive substances  Helps finding appropriate recycling or waste treatment method – Often pretreatment is needed, eg.  Composting of biomass, rotting or incineration  The solidification or filtration of fluids  The places of deployment of waste should be planned ahead  The protection of workers should be planned ahead

Conclusions  How and where waste is treated depends on the type and amount of waste generated.  Central for the waste treatment is that: – The local/regional waste treatment possibilities (eg. Dumping grounds, incineration) – The capability of transportation and treatment and the need for additional instruments (eg. Radiation measuring equipment) – The changes of the level of radiation during different phases of waste treatment chain – The appropriate dumping of waste from the beginning so, that radioactive substances are hindered from drifting into ground- and surface water and, that the radioactive material is finally covered with enough non-radioactive material to damp the outer radiation

Recommendations  Preparedness for the later phase of radiological accidents is needed in many sectors  The legislation should be developed and questions on responsibilities solved