Experience of decommissioning of the Rikkyo University Reactor

General Convention of the American Episcopal Church at Honolulu took up the proposal from the Diocese of Washington to donate an atomic reactor for peaceful uses to some institution in the Far East in September 6, 1955. An Atomic Energy Committee was appointed to consider the matter. The Rev William Pollard, Director of the Oak Ridge Institute of Nuclear Studies and a priest of the Church visited Rikkyo University as a member of the above committee and talked with members of the University staff. In response to the development of the situation, the Institute for Atomic Energy Rikkyo University was established in May 20, 1957. General Convention of the Church at Miami deliberated on the report of the Committee and adopted a resolution approving the raising of funds for making a gift of an atomic reactor to Rikkyo University in October 13, 1958. The Rikkyo University Research Reactor became critical with 57 fuel elements Dec. 8, 1961. In April 20, 1974, the Inter University Program for the Common Use of the Rikkyo University Research Reactor was realized under financial supports from the Ministry of Education as the first case for private university institution. In November 18, 1986, The First Asian Symposium On Research Reactors (ASRR-1) was held, the Institute acting as the host organization. The end of 1996, the Rikkyo university decided the Rikkyo University Reactor stop operation considering that the reactor have contributed for progress of science using the research reactor sufficiently and also rewarded the good intention of the Episcopal Church. The reactor operated last run in Dec. 15, 2001 and stopped. The followings are the decommission process of the reactor and present state of the institute. (author)