As we saw above, the most important source of radioactive waste products is the fuel itself. We can illustrate the fuel cycle for a typical thermal reactor as shown in Figure 8.3. Essentially, there are two alternative routes for dealing with the spent fuel. In route A the fuel is passed through a reprocessing plant, which allows recycling of the plutonium and uranium and produces a highly active liquid waste stream. This latter stream may he passed to an interim liquid

Time after discharge— 5 years————————————————————————- 20 years

Figure 8.3: Options for management of high-level active wastes.

storage stage, followed by solidification in one form or another, before being passed to an engineered surface store, where it is kept for about 50 years. Ulti­mately the solidified waste material would be disposed of in suitable geological formations as discussed in Section 8.5. In route В the spent fuel is stored either at the reactor site or away from it in a specially engineered spent fuel store, be­fore ultimate geological disposal. As shown in Figure 8.2, the option of not re­processing fuel leads to a much longer period before the waste reaches the same level of hazard as the original uranium ore. The options presented by routes A and B are discussed in the next two sections.