Hamaoka holds Nankai Trough quake exercise

Nuclear plant workers test procedure for keeping reactors cool

Kyodo

Chubu Electric Power Co. on Wednesday held a disaster drill, open to the media at its Hamaoka nuclear power plant in Omaezaki, Shizuoka Prefecture, in preparation for a magnitude-9.0 quake in central to western Japan.

The Hamaoka power plant is at risk, should a major earthquake strike the Nankai Trough off the Pacific coast of central and western Japan.

The drill assumed an earthquake with an intensity of 7 — the top level on the Japanese seismic scale — hit the prefecture, knocking out power throughout the station. The hypothetical quake damaged power lines running from the reactor building to the power supply outside, hindering the use of emergency power generators.

Under instructions from disaster management headquarters, the plant workers followed the procedures for connecting the power system for reactor No. 5 to generators outside the station to keep the core’s cooling system operating.

A four-member team put up a 13.5-meter makeshift utility pole made from metal tubes, and used it to support electrical cables running between the generators and the reactor.

The company said the workers are prepared to set up several such poles to restore power at the plant within three or four hours.

The workers also ran through procedures for setting up mobile power generators of the type dispatched to hospitals and police stations in emergencies, or for running emergency command centers.

Meanwhile, Naoto Kan, who was prime minister at the time of the nuclear meltdowns at the Fukushima No. 1 power plant in March 2011, blasted Chubu Electric’s plan to restart the Hamaoka power station.

Kan, who urged the company to shut down all reactors at the plant in May 2011, told reporters during a visit to Nagoya on Saturday that the company should decide on its own to decommission the reactor.

In February, the company applied to the Nuclear Regulation Authority for safety checks required to reactivate the plant’s No. 4 reactor.

Last September, the company adopted additional safety measures at reactors 3 and 4 and it continues to explore necessary measures for No. 5.

Kan criticized the company, claiming that conditions at the plant have not changed since 2011. He said that company officials, not the NRA, should call off the plan to restart the plant.