In spite of being flatly rejected by the state Coastal Commission, PG&E officials have not ruled out applying for permits to conduct high-energy seismic surveys next year offshore of Diablo Canyon nuclear power plant.
Jearl Strickland, PG&E’s manager of nuclear projects, said that before the utility can decide how to proceed, it needs to analyze the commission’s final decision as well as the considerable amount of data it has already gathered via onshore and low-energy offshore seismic surveys.
“It’s a robust and thorough process,” he said. “It will be sometime next year before a final decision is made on how to move forward.”
Meanwhile, biologists involved in two wildlife monitoring programs begun as part of the seismic surveys say information they have gathered will increase scientific knowledge of sea otters and harbor porpoises.
On Nov. 14, the Coastal Commission unanimously rejected PG&E’s request to use extremely loud blasts to map earthquake faults offshore of Diablo Canyon. The commission ruled the utility did not provide enough information about the effects of the surveys or adequately mitigate for them.
Strickland acknowledged that the determination creates a very high threshold should PG&E decide to reapply to do seismic surveys a year from now.
“The commission made it clear that it does not support high-energy seismic surveys,” he said. “At this point, I don’t see a clear path forward.”
In addition to analyzing data already on hand, PG&E will investigate using alternative technologies, look at recent work done by the U.S. Geological Survey on the Hosgri Fault and see how the Coastal Commission reacts to plans to conduct high-energy surveys offshore of San Onofre Nuclear Generating Station in Southern California.
The state Public Utilities Commission authorized PG&E to spend up to
$64 million of ratepayer money to perform the onshore and offshore seismic mapping. To date, the utility has spent half that amount, Strickland said.
The CPUC supported the high-energy seismic work and is waiting to see what PG&E decides.
“PG&E will need to review its options and decide if it will reapply to the Coastal Commission in 2013 in order to best figure out what the seismic risks are,” said Terrie Prosper, CPUC spokeswoman.
The concern that crystallized opposition to the sonic blasting was the harm it could do to marine life. Two of the most vulnerable species are sea otters and harbor porpoises, both of which are territorial and most vulnerable to harm if displaced by the loud noises or exposed to them for an extended period.
PG&E funded monitoring programs for both species that were begun before the surveys’ start in order to gain baseline information. One program will continue for the next three years, and the other has been discontinued.
Tim Tinker, a sea otter biologist with the USGS, said 54 sea otters were captured and implanted with radio transmitters and dive recorders to track their movements and behavior. This is the same monitoring done on otters in Big Sur, Monterey Bay and a decade ago in San Simeon.
Originally, the goal was to monitor how the seismic surveys affected the otters’ behavior. Although the surveys have been canceled, biologists will continue daily monitoring of the tagged otters in an effort to better understand trends in the population, particularly why the local population stopped growing in 2006.
“All of the animals are doing quite well right now,” he said.
One of the reasons the population stopped growing was that an inordinate number of them were being bitten and killed by great white sharks.
Biologists theorize that infectious disease is causing the otters to behave in ways that increase the likelihood of being bitten.
Another monitoring program targeted the Morro Bay population of harbor porpoises, estimated to consist of about 2,000 animals. Again, the goal was to record how the porpoises reacted to the sonic blasting.
Biologists with the National Marine Fisheries Service flew aerial surveys of the county’s coastline, counted porpoises and installed underwater acoustic devices to record the porpoises’ echolocation clicks and ambient noise.
The program has been discontinued, but the data collected during the baseline phase will shed light on the Morro Bay population and allow biologists to refine their techniques for estimating porpoise numbers, said Karin Forney, a research biologist with NMFS.
“Harbor porpoises are one of the species that are often negatively impacted by human activity,” she said. “We had a unique opportunity to collect data that will improve our understanding of the species.”
The controversy surrounding the seismic testing also had an unexpected benefit. It increased awareness of a cryptic species. Harbor porpoises feed in small groups and avoid human contact so even fishermen and others who spend time on the water rarely see them, Forney said.
“To me, it’s nice that the Morro Bay community has an increased awareness of this species,” she said. “You can’t appreciate something you don’t see.”