The operator of the Hamaoka nuclear power plant in Shizuoka Prefecture said Wednesday its investigation found no active geological faults under or around the site, which was forced to shut down in 2011 after the plant's operation was deemed risky.
Chubu Electric Power Co. plans to submit the results of the probe to the Nuclear Regulation Authority after it applied for the nuclear watchdog's reactor safety review in February, seeking to resume its operation.
Critics of the decision say the Hamaoka complex could find itself at the epicenter of a powerful earthquake in future.
"Everyone in the prefecture knows that the Hamaoka plant is right above the source zone (of the possible quake)," said one official from the prefecture, urging the utility to expand the scope of its investigation.
Nuclear plant operators are not allowed to build reactors above active faults, which are defined as those that have moved in the last 120,000 to 130,000 years.
Chubu Electric concluded that the faults that run near the plant and under its premises "have not moved at least in 130,000 years" and they will not trigger earthquakes.
Following the 2011 Fukushima nuclear disaster, the previous government led by the Democratic Party of Japan asked Chubu Electric to halt operations at the Nos. 4 and 5 reactors at the Hamaoka site. It also barred reactivating the No. 3 reactor that was undergoing a checkup at that time, citing a lack of measures against quake and tsunami hazards.
Two of the five reactors at Hamaoka were retired in 2009.
None of Japan's 48 commercial reactors has passed the NRA's safety assessment based on new regulations introduced in the wake of the nuclear crisis, although 19 applications have been made to do so.