Japan starts shutting down Hamaoka nuclear reactor

TOKYO—The operator of Japan’s ageing Hamaoka nuclear plant, located near a tectonic faultline southwest of Tokyo, on Friday began shutting down one of its two running reactors, a plant official said.

Chubu Electric Power started installing control rods into the number four reactor of the power plant early Friday, the first procedure in the operation, said Kazuhide Enoo, an official at the plant.

“We plan to stop electricity generation in the morning, and then the reactor is scheduled to be non-critical around noon today,” Enoo said.

“So far procedures went smoothly as no problems were found,” he said, adding that the reactor was expected to be in “cold shutdown” status “within a day at the earliest.”

Prime Minister Naoto Kan last week called for the closure of the plant, eight weeks after a massive quake and tsunami damaged the Fukushima Dai-ichi nuclear plant northeast of Tokyo, sparking the world’s worst atomic crisis since Chernobyl in 1986.

Seismologists have long warned that a major quake is overdue in the Tokai region southwest of Tokyo where the Hamaoka plant is located. It is only 200 kilometers (125 miles) from the capital and megacity of Tokyo.

The Hamaoka plant has five reactor units, but only two are currently running – numbers four and five. Reactors one and two, built in the 1970s, were stopped in 2009, and three is undergoing maintenance.

The firm also plans to begin shutting down the number five reactor on Saturday.