Alteration of reactor installations (Units 1, 2, 3, 4, 5 and 6) in Fukushima Nuclear Power Station No. 1 of the Tokyo Electric Power Company, Inc

This is the report by the Atomic Energy Commission to the Prime Minister, and the report by the Committee on Examination of Reactor Safety to the Atomic Energy Commission of Japan concerning the subject matter is attached. The alteration of the reactor facilities are as follows. The uranium-235 enrichment of the fifth fuel load for Unit 1 is changed to about 2.2 wt% from about 2.6 wt%. The control systems for inflammable gas concentration are installed in the containment facilities of Unit 4 and 5. Turbine-building ventilation and exhaust system for Units 1, 2, 3, 4, 5 and 6 is altered. The capacity of the spent fuel storage pool for Unit 1 is changed to about 156% of the amount for one reactor core from about 150%. The safety of the reactor facilities is well confirmed. (Mori, K.)