PG&E's seismic testing plan rejected Siding with a broad coalition of environmentalists, the California Coastal Commission has unanimously rejected a plan by Pacific Gas and Electric Co. to study offshore earthquake faults near the Diablo Canyon nuclear plant by blasting the seabed with air cannons. Thorough testing soughtPG&E wants to extend the plant's operating license and has been under pressure from state officials to conduct more thorough seismic tests in the area. "Reducing the uncertainty of the seismic hazard at Diablo Canyon - does that outweigh the environmental harm that we've talked about?" PG&E Director Mark Krausse asked coastal commissioners at a hearing Wednesday. The vote came after more than two hours of public testimony, as environmentalists, fishermen and Central Coast residents spoke out against PG&E's plan.