Researchers urge survey of possible active fault under Oi plant

June 09, 2012


Two scientists are calling for an inspection of a possible active fault line under the Oi nuclear power plant in Fukui Prefecture before two reactors are brought back online.

Professors Yasuhiro Suzuki of Nagoya University and Mitsuhisa Watanabe at Toyo University have compiled data indicating that the F-6 fault under the Oi plant could be active. The two researchers specialize in tectonic geomorphology.

An active fault could cause future earthquakes.

Kansai Electric Power Co., the Oi plant operator, has said the fault is not active, and there is no need for further investigation.

According to the utility, 15 faults lie under the Oi plant. KEPCO said it conducted drilling and other types of surveys on the F-6 fault before filing applications for the construction of the No. 3 and No. 4 reactors. The two reactors first came online in December 1991 and February 1993, respectively.

But the two researchers, after examining past documents and aerial photos, said they found clay deposits on the fault surface that indicate the fault may have moved in the relatively recent past. They said the age of the sediment over the fault has yet to be determined.

“Investigations by Kansai Electric have been insufficient,” Suzuki said. “There are no grounds to deny fault activity.”

(This article was written by Toshio Kawada and Ryuta Koike.)

  • 1
submit to reddit
The Asahi Shimbun

The Asahi Shimbun

  • The Asahi Shimbun

More AJW