Dominion rechecking seismic data

Nov 18 - McClatchy-Tribune Regional News - Rusty Dennen The Free Lance-Star, Fredericksburg, Va.

Dominion Power is looking at whether any changes are needed in its seismic analysis for a planned third reactor at North Anna Power Station.

That possibility was raised in a report Wednesday to the Nuclear Regulatory Commission.

Dominion, in its applications to the NRC for an early site permit and a combined construction and operating license for Unit 3, says it used the most up-to-date seismic data available at the time.

Those applications were filed in 2003 and 2007, respectively.

In an email to employees, Dominion wrote: "The company is now assessing whether any changes should be made to those licensing documents based on more recent analytical techniques."

An early site permit allows a utility to "bank" a site for 20 years, resolve environmental and safety issues, and complete preliminary site work. A combined license governs the construction and operation of a new reactor.

Dominion said in the email that it does not expect to complete its seismic assessment for Unit 3 until the third quarter of next year. The company said it will decide on a timetable for building Unit 3 when the NRC acts on its combined license application sometime in late 2014.

The magnitude-5.8 quake on Aug. 23 that shook the power plant on Lake Anna exceeded predicted ground motion for Unit 3.

The quake automatically shut down Units 1 and 2, and it was determined that the ground motion exceeded limits for which those units were designed.

Inspections by Dominion and the NRC determined that no significant safety or operating systems were damaged.

The NRC last week gave North Anna the go-ahead to restart Units 1 and 2.

Rusty Dennen: 540/374-5431

Email: rdennen@freelancestar.com