Editor's note: This is The Tribune's top local news story of 2012 as selected by the newsroom staff.
Few local controversies have spurred as many environmentalists to action and had as far-reaching consequences as plans by Pacific Gas and Electric Co. to conduct high-energy seismic surveys offshore of Diablo Canyon nuclear power plant.
The utility had planned on doing the deep earthquake fault mapping in November and December. The company had received most of the permits it needed to do the work until it ran into a regulatory brick wall at the California Coastal Commission.
After an emotional daylong hearing in November in Santa Monica, the commission unanimously rejected the proposal. In the run-up to the meeting, the agency had gotten tens of thousands of e-mails and letters opposing the project from environmental activists from across the state.
This resounding rejection has left both PG&E and Southern California Edison, owners of the San Onofre Nuclear Generating Station, unsure how to proceed with their ongoing seismic threat assessments. Southern California Edison had planned on conducting its own high-energy surveys offshore of San Onofre in March.
We will meet with Southern California Edison in January, said Alison Dettmer, Coastal Commission deputy director. They are forming a seismic independent peer review panel similar to the one at Diablo Canyon, but their plans for high-energy surveys are on hold.
High-energy seismic surveys consist of using ship-towed air guns to emit very loud blasts of sound into the ocean, which penetrate deep into the Earths crust and bounce back to be picked up hydrophones. This data allows seismologists to create three-dimensional images of offshore faults at depths where earthquakes occur.
The March 2011 Fukushima nuclear disaster in Japan, which was caused by an unexpectedly powerful earthquake and resulting tsunami, prompted legislators and several state agencies, including the California Public Utilities Commission, to call for state-of-the-art seismic testing around the states two nuclear plants.
What galvanized opposition to the sonic blasting was the damage it could do to marine life. At a minimum, it would kill fish larvae near the air guns, disrupt commercial fishing and harass marine mammals.
PG&E maintained that the surveys would do minimal damage and pointed to the fact that they are done regularly in the Gulf of Mexico and other locations without mass fish die-offs and other dire consequences predicted by environmental activists.
But the activists werent buying it, and neither did the Coastal Commission. The commission ruled that the utility did not provide enough information about the effects of the surveys or adequately mitigate for them.
Seismologists with PG&E are busy studying the data they have already collected from onshore 3D surveys as well as low-energy offshore surveys, both of which garnered essentially no opposition. It will be early this year before the utility decides whether it will reapply to do high-energy surveys in November and December.
The Tribune's top stories of 2012
1. PG&E's plans to conduct seismic surveys offshore of Diablo Canyon nuclear power plant | 2. The ban on disposable plastic bags at SLO County retailers | 3. Accreditation and budget challenges at Cuesta College | 4. The Lisa Solomon controversy in the Paso Robles Police Department | 5. Violence by patients on staff at Atascadero State Hospital