Fault Line Study Near San Onofre Will Be Made Public

Friday, May 4, 2012
By Alison St John

Southern California Edison, the majority owner of the San Onofre nuclear power plant, plans to do more thorough studies of fault lines discovered since the plant was built in the 1980s. The Oceanside subduction fault runs just off shore and was discovered about a decade ago.

The company has expanded its research plans since the Fukushima disaster, to see if safety measures at San Onofre are adequate. San Onofre has a 30 foot sea wall, about the same height as the sea wall at Fukushima which was overwhelmed after a magnitude-9 earthquake and tsunami.

Gary Headrick is with San Clemente Green, a group concerned about the location of the San Onofre Nuclear Plant, which is within 50 miles of 8 million southern California residents. He would like to see the plant decommissioned and said he sees the earthquake studies as a delaying tactic.

“They are resisting having independent pier review,” he said, “and what does that tell us? I think they want to control the outcome of the study.“

Edison declined to be interviewed, but Neal Driscoll of Scripps Institution of Oceanography, who will conduct the research, said this new data will be open source.

“That means it will be available to every scientist across the country, and the public,” Driscoll said, “so the data will be public data and people can evaluate it and objectively look at these structures offshore. “

Driscoll said ships should start mapping fault lines beneath the ocean floor near San Onofre in November, using new 3D technology. The timing will depend on permits to be granted by Marine Fisheries and the California Coastal Commission. The actual mapping would take less than three weeks, to have minimum effect on marine mammals.

The research will be done in collaboration with other scientists, including Graham Kent, the Seismological Director of the University of Nevada, Reno.

Driscoll said a number of scientists from around the country will be able to see the data as it is collected. The data will then go through quality control and be released and made widely available for analysis four to six weeks later.

He said, even if there is a range of interpretations, they will be taken into account when calculating the potential effects of ground motion near the nuclear power plant.