Insignificant Effects from Earthquake Off Fukushima Prefecture This Morning

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At about 5:59 a.m. on November 22, an earthquake with a magnitude of 7.3 occurred with its epicenter offshore of Fukushima Prefecture. As a result of the earthquake, at about 6:10 a.m., the spent fuel pool cooling/cleaning system at the Fukushima Daini-3 Nuclear Power Plant (BWR, 1100MWe), owned and operated by the Tokyo Electric Power Co. (TEPCO), shut down automatically, but resumed at about 7:47 a.m.

Apart from this, there were no abnormalities in regard to equipment or facilities at any reactor, and no significant changes in readings at monitoring posts were reported.

Maximum readings on seismometers at the Fukushima Daiichi and Fukushima Daini NPPs were as follows:

Fukushima Daiichi	Horizontal direction: 54.2 Gal (Unit 6)
	Vertical direction: 45.5 Gal (Unit 6)
Fukushima Daini	Horizontal direction: 68.4 Gal (Unit 1)
	Vertical direction: 65.6 Gal (Unit 4)

Maximum standard ground motion (Ss) for the Aseismic Design of both NPPs is 600 Gal in the horizontal direction and 400 Gal in the vertical direction (Ss-2 each). Given this, it is readily understood that there would be no effects from this earthquake.