HOUSTON Oct 12 The U.S. Nuclear Regulatory
Commission said its latest analysis of seismic faults near PG&E
Corp's Diablo Canyon nuclear station in California
showed the coastal plant could withstand an earthquake generated
by an offshore fault identified in 2008, according to a
statement on Friday.
The NRC's report focuses on the latest identified earthquake
source, called the "Shoreline fault," just offshore from the
plant in San Luis Obispo County, about 183 miles (294 km)
northwest of Los Angeles.
"Both PG&E and the NRC are continuing to look at the seismic
characteristics of the Shoreline fault," said NRC spokesman
Victor Dricks. "This research information letter represents the
staff's latest analysis and basically concludes that the plant,
as designed, would withstand any earthquake the Shoreline fault
Diablo Canyon operator Pacific Gas & Electric notified the
NRC about the Shoreline fault in 2008. At 2,240 megawatts,
Diablo Canyon is the largest of the state's two nuclear power
plants, supplying about 10 percent of the state's power needs.
An NRC team visited the site in 2011, the agency said.
Analysis from the visit and available information indicates that
ground motion from earthquakes the Shoreline fault could
potentially generate would fall within Diablo Canyon's existing
design limits, the agency said in its report.
The plant's design limits are based on ground motion
associated with an earthquake from the larger Hosgri fault near
the plant, the NRC said.
Separately, PG&E is pursuing a $64 million seismic study to
better understand the hazards posed by potential earthquakes
near the plant.
In August, the California State Lands Commission voted to
allow the utility to move forward with tests using powerful
sonar devices despite concerns about the impact on marine life.
PG&E's application to extend the Diablo Canyon reactors'
operating licenses beyond 2024 and 2025 will not be finalized
until the seismic study is completed.
For the NRC, Diablo Canyon must perform additional
earthquake evaluations, as well as a "walkdown" to identify any
near-term actions for enhancing earthquake resistance as part of
the agency's ongoing response to the 2011 Fukushima Daiichi
nuclear accident in Japan which was triggered by an earthquake