2008 年 43 巻 2 号 p. 135-139
An approach how and what to discuss the decommissioning of large accelerator facilities has been overviewed through a case study on Stanford Linear Accelerator Center (SLAC) in USA, which is also under discussion in Japan. SLAC has its own framework on radioactive waste management, however it is still involved in difficulties about the treatment of large amount of low-level radioactivated materials, such as shielding blocks or soil surrounding the underground accelerator. Introduction of disposition criterion of solid material was deferred by US regulatory authority. SLAC is also focusing on the environmental protection using Environmental Restoration Project due to United States Environmental Protection Agency (USEPA). Remedies for the circumstance water or land which are affected by the SLAC's past operations are started. Every kind of pollution including radioactive contaminations are targets of remedies. It means they address the inclusive management of various risks, such as chemical hazardous risk and radiological consequence risk. It is helpful for other accelerator facilities over the world which program decommissioning.