State lawmakers raised sharp questions Monday about whether California's nuclear power plants can withstand a major earthquake and tsunami like the ones that have left Japan scrambling to control radiation coming from some of its reactors.
Even before officials from the state's nuclear plant operators laid out their extensive preparations and safety plans to protect the public in the event of a temblor, Sen. Sam Blakeslee asked why Pacific Gas and Electric Co. located its Diablo Canyon plant near not one but two fault lines, including the recently identified Shoreline fault off the coast.
"I'm a little concerned that PG&E ... failed to notice a fault of this size," said Blakeslee, a Republican from San Luis Obispo who has previously pushed for new seismic reviews of the plants.
Outside the hearing room, Daniel Hirsch, a lecturer in nuclear policy at University of California, Santa Cruz, noted California's reactors are in one of the most seismically active areas of the world after Japan. "What's going on in Japan could happen here," he said.
But Japan's plants were not designed to handle the ground movement or wave heights they were subjected to during the March 11 disaster, said Steve David, director of site services at Diablo Canyon.
Both Diablo Canyon and California's other commercial nuclear plant, San Onofre, have been designed to survive much larger forces, utility representatives testified.
"We've gone back this week and verified that (safety) equipment is in place and that the operators have been trained," David said.
The senators are reviewing whether California's nuclear power plants and natural gas pipelines are safe from earthquakes as Japan's crisis brings up uncomfortable similarities to the nuclear plants on the U.S. West Coast.
"Japan has always been a leader in preparedness," said Sen. Ellen Corbett, the San Leandro Democrat who chairs the Senate Select Committee on Earthquake and Disaster Preparedness, Response and Recovery. "It's time to revisit the safety of these plants in light of what we have learned from Japan."
Corbett noted that state seismic experts have estimated there is a 2 percent to 3 percent chance of a major earthquake in California each year, and a 46 percent chance of a quake with a magnitude of 7.5 or greater within the next 30 years.
The White House last week asked the Nuclear Regulatory Commission to conduct a comprehensive review of safety for all 104 U.S. nuclear plants after radiation leaks and explosions at Japanese plants raised fears on both sides of the Pacific. The Union of Concerned Scientists on Thursday accused the NRC of lax oversight at some nuclear plants that were subjects of special inspections last year.
But at the same time, the Obama administration has been seeking billions of dollars in federal guarantees for the nuclear energy industry, and nuclear energy has seen a resurgence of interest as concerns grow about greenhouse gases emitted by burning hydrocarbons like coal and oil.
Concerns about seismic safety have haunted California's two plants for decades as geologists identified new faults near the generators that could produce earthquakes and safety problems made headlines.
A 2008 NRC report revealed that a battery powering safety systems at Southern California Edison's San Onofre plant, 70 miles southeast of Los Angeles, had not worked for four years.
The Union of Concerned Scientists report last week noted a finding that emergency cooling-water valves failed in 2009 at the Diablo Canyon plant near San Luis Obispo as a result of repairs that were made to another set of valves 18 months earlier.
The utilities that operate the plants maintain they were built to withstand the largest quakes expected in the region and safety systems are in place.