[en] Dated December 9, 1982, the Japan Atomic Energy Research Institute submitted the notice on the dismantling of the nuclear reactor facility (JPDR) in Tokai Laboratory to the Director of Science and Technology Agency, based on the law concerning the regulation of nuclear raw materials, nuclear fuel materials and nuclear reactors. In this report, the background and the outline of the plan concerning the dismantling of the JPDR are described. In Europe and USA, already more than 30 power reactors have finished the operation, and the necessary measures have been taken. In Japan, the JPDR is the first case. To prepare for the decommissioning of large power reactors, the measures to be taken have been studied in various countries and also in IAEA and OECD. The measures are divided into three, (1) closure of nuclear facilities and appropriate management, (2) isolation of radioactive substances by shielding and others, (3) dismantling and removal of structure. It is planned to utilize the dismantling of the JPDR for developing the techniques and facilities used for the decommissioning. It was judged that the dismantling according to the plan would not cause any hazard. (Kato, I.)