— LOS ANGELES (AP) — California coastal regulators were set to weigh in Wednesday on a utility's contentious plan to map offshore earthquake faults near a nuclear power plant by blasting loud air cannons.
Pacific Gas & Electric Co., which operates the Diablo Canyon facility, has proposed conducting a seismic survey that involves firing sonic pulses into the ocean. Sensors on the seafloor would pick up the echoes to create 3-D maps of geologic faults.
Environmentalists, fishermen and even the California Coastal Commission's staff have lined up against the project, fearing the high-decibel sounds would disturb sensitive marine mammals. In a report this month, the staff urged the panel to deny a permit to PG&E, citing "significant and unavoidable impacts to marine resources."
The staff estimated more than 7,000 sea mammals would be affected by the ear-piercing noise, including fin whales, blue whales, humpback whales, and harbor porpoises. The 12 commissioners, who take staff opinion into consideration, have the final say.
If they reject the project, the company could reapply at a later time. On the eve of the vote, PG&E spokesman Blair Jones said if the permit is denied, the utility would need to study the decision to plot its next move.
Charles Lester, the commission's executive director, said seismic hazards around the seaside plant need to be better understood, but "the case hasn't been made that this particular test is necessary in order to get those answers."
PG&E disagreed, saying that high-tech imaging is needed to understand the complex geology that other types of studies can't provide. The utility said similar research has been done around the world without long-term harm to animals.
The damage that strong shaking can cause to nuclear reactors came under scrutiny after the 9.0-magnitude earthquake off Japan's coast triggered tsunami waves, which swamped the Fukushima Dai-ichi plant last year.