The disposal of nuclear fuel wastes

Although used fuel from the CANDU reactor can be safely stored in pools at the reactor site for many years, AECL, with the help of many government departments, industry, universities and Ontario Hydro, is conducting an intensive research program to demonstrate disposal deep underground. The program, which is concentrating on disposal in stable, hard rock formations (plutons) of the Canadian Shield, consists of three phases. In the first (concept verification) phase, research will be done on several different types of rock to assess whether the concept of disposal in hard rock plutons will meet the basic objective of isolating the radioactive wastes. The second phase is the selection of a site for a demonstration facility. Technically suitable sites from among the 1500 plutons in Ontario would be defined using the results of the research program. However, the final choice will be made by governments in consultation with local elected representatives. Tests not involving radioactive material would be done to assure soundness of design. Immobilized wastes would then be placed in the facility and extensive monitoring done for several years to confirm the safety of the disposal method. When this is complete, probably by the late 1990's, a decision to construct a full-scle commercial facility could be taken. (LL)