aDecontamination factor :

initial concentration final concentration bWhere no data are listed it implies lack of information and not the unsuitability of the process.

3. Release to the environment, if material is below the maximum permissible concentration (MPC) in 10 CFR Part 20 appendix B, Table II.

4. Disposal by incineration according to 10 CFR §20.305, especially for waste oils and scintillation fluids.

5. Disposal of certain specific waste without regard to its radioactivity 10 CFR §20.306 (e.g., 0.05 mCi 3H or 14C).

6. Specific procedures approved as part of licensing to handle radioactive materials.

Radioactive waste is normally disposed of as a solid, except for liquids released to sanitary sewers or other water systems when radioactivity levels are below the maximum permissible concentration (MPC). In contrast to other types of waste, where pollutants can be eliminated by treatment, radioactivity can only be reduced by decay time. Thus the disposal methods used at NRC-authorized disposal sites are for solids and are based on the decay time required to make them non-radioactive. The correct preparation of radioactive waste is the first step to ensure the waste is disposed of economically and according to all applicable regulations.

Conditioning of radioactive wastes can include segregation, pretreatment, processing, and packaging. These techniques are covered in other sections of this chapter. Here, conditioning refers only to the various immobilization techniques used to prevent radioisotopes leaching into the environment. Immobilization is often used to help meet the NRC stability requirements for Class B and C waste and even for some forms of Class A and mixed wastes. The principle immobilization techniques are cementation, bitu-minization, polymerization, and vitrification. All of these techniques will increase the volume of radioactive waste.

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