Chubu Electric Power Co. has announced a plan to decommission two aging reactors at its Hamaoka Nuclear Power Station in Shizuoka Prefecture and build a new reactor as a replacement. The decision to decommission the No. 1 and No. 2 boiling water reactors with a combined output of 1.38 million kW is reasonable. But the decision to build a new advanced boiling water reactor with an output of 1.4 million kW is questionable. The nuclear-power station is situated over a cluster of potential hypocenters for the magnitude-8 "Tokai Earthquake," which could happen anytime.
The No. 1 reactor started operation in March 1976 but has been shut since 2001 when a steam pipe was broken. Water leakage also occurred at the bottom of its pressurized vessel, casting doubts on its safety. The No. 2 reactor started operation in November 1978 but has been idle since 2004 due to a series of troubles.
The Hamaoka nuclear-power complex, with five reactors, has a total output of about 5 million kW and is Japan's second-largest nuclear complex. In July 2003, local residents filed a lawsuit seeking permanent closure of the No. 1 to No. 4 reactors. In September 2004, the power company announced a plan to replace the shroud structure surrounding the No. 1 and No. 2 reactors' cores. But this work has not progressed.