A 5.8-magnitude earthquake that rocked the US East Coast spotlights the need to analyze new seismic risks for nuclear plants and to invest in upgraded defences, said the chairman of the US’s Nuclear Regulatory Commission (NRC) on 1 September.

The quake on 23 August shut down Dominion Resources Inc’s North Anna nuclear power plant, which is only about 10 miles from the earthquake’s epicentre near Mineral, Virginia.

It is too soon to say what kind of changes the utility may need to make for the NRC to allow it to reopen, Gregory Jaczko told Reuters in his first interview since the quake.

Since 1991, the Nuclear Regulatory Commission has been working toward requiring plants to more regularly model quake risks using new seismic data.

“It’s something we’re working through, and I certainly expect that in some way, shape, or form, that (some) plants will need to make modifications as a result,” said Jaczko.

The regulator is combing the North Anna plant for damage after the quake – for the first time for an operating US plant – appears to have exceeded the plant’s design rating.

“While in some regards the earthquake may have been larger than what we anticipated, at this point we haven’t seen any indications of equipment that has shown a performance problem as a result of that,” said Jaczko.

For more nuclear news click here