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The linked production, use and subsequent management of nuclear fuel. A closed cycle recovers some material for reuse; it still generates radioactive wastes.

Immobilisation of radioactive waste in a glass matrix. glass composition, durability, secondary phases and the complete package affect performance.

evaporation transfers water to a vapour stream and retains mainly nonvolatile solutes in a concentrate. It can give substantial volume reduction and works across many dissolved-solute compositions. Its disadvantages are heat demand, scaling and corrosion; aerosols, entrainment or volatile radioactive species can contaminate the condensate. Condensate must therefore be sampled or monitored rather than assumed releasable, while the concentrate requires radioactive waste conditioning. A demister limits droplet carryover but does not remove a genuinely volatile contaminant.

ion exchange transfers dissolved radioactive ions to an exchanger, often an ion-exchange resin. It is useful for polishing relatively dilute aqueous streams and can provide selective removal without evaporating the bulk water. Competing inactive ions consume capacity, suspended particles foul the bed, and a neutral or poorly retained species may pass through. Breakthrough measurements determine when the exchanger ceases to meet its target; exhausted resin or regeneration liquors become secondary radioactive waste. Separation performance must be established for the actual feed chemistry, not inferred from the name of the radionuclide alone.

Chemical precipitation with solid–liquid separation uses precipitation, coprecipitation and adsorption to carry contaminants into solids, followed by settling or filtration. It can treat substantial volumes and complex feeds at moderate equipment cost. Its disadvantages are a relatively bulky sludge, incomplete removal of soluble species, and sensitivity to pH, complexation and competing ions. The sludge must be dewatered and conditioned, and the clarified liquid checked for residual radioactive activity. Polishing by another method may still be needed.

In each case, measure both the treated stream and the residue so that the radioactive inventory balance can be checked. Treatment transfers or concentrates radioactive activity; only radioactive decay reduces the number of radioactive parent nuclei. These methods and the distinction between treatment and conditioning are set out in the institutional waste-management framework.^[ref]

A useful three-product account is a demonstrated site end state, recovered materials, and wastes requiring disposal or continuing management. It keeps the land outcome distinct from the material streams.

The first product is the land and any retained buildings in the specified nuclear decommissioning end state. Characterisation and final surveys must show that the remaining inventory is consistent with the intended reuse and any retained restrictions. Demolition is a possible means of reaching that state, not its definition. The associated records and final radiological evidence are part of the handover.

The second product is reusable or recyclable material and equipment. Segregation and, where appropriate, decontamination prevent clean bulk material from being unnecessarily mixed with contaminated material. Release from radiological control requires demonstrated radiological clearance; conventional chemical hazards still need their own management.

The third product is waste: both ordinary unrecoverable demolition debris and radioactive waste that remains under control. Activated structures, contaminated components and secondary cleaning wastes may require different treatment and packages. spent nuclear fuel, if still present, requires its own inventory and management route rather than being counted as ordinary scrap. Thus the material outputs can alternatively be tabulated as reusable material, conventional waste and radioactive waste, while the restored site is the overarching project deliverable. The source does not define a unique named three-product taxonomy.^[ref]

The physical and chemical form in which radioactive waste is immobilised for handling, storage or disposal. Its durability is distinct from that of its container and surrounding engineered barriers.

Control of radioactive wastes from generation through treatment, conditioning, storage and disposal. Concentrating a radionuclide in a smaller stream changes its location, not its radioactive decay law.