FRESNO, Calif. (AP) — A gas pipeline that exploded at a sheriff's gun range in Central California, injuring 11 people, had been inspected twice in April for gas leaks, and no leaks were found, Pacific Gas & Electric Co. said Sunday.
PG&E said its crews did a ground survey of the pipe on April 1 and an aerial survey on April 16.
Authorities say Friday's explosion at the Fresno County Sheriff's gun range occurred while a county employee was using a front-loader to build a dirt berm to confine gunfire to the range. The California Public Utilities Commission is investigating the explosion in cooperation with the federal Pipeline and Hazardous Materials Safety Administration, but PG&E says it appears a vehicle damaged the 12-inch pipeline.
The utility detected a drop in pressure in the line seven minutes before it received a report of the explosion, it said.
The blast sent 11 people to the hospital and shut down a nearby highway and rail line, as it created a tower of flames. Six people remained in the burn unit at Community Regional Medical Center on Sunday — four in critical condition and two others in stable condition, said Fresno County sheriff's spokesman Tony Botti.
PG&E's natural-gas operations have been under scrutiny since a fiery 2010 PG&E pipeline blast killed eight people in the San Francisco suburb of San Bruno. National Transportation Safety Board investigators blamed faulty safety practices by PG&E and lax oversight by state regulators for the blast.
PG&E has previously said the pipeline in Friday's incident was surveyed in 2013, and there was about 40 inches of cover between the pipe and the surface in accordance with PG&E standards and federal code. The land, however, had been under constant construction in recent months, Botti said.
PG&E also says it was not notified in advance of any work in the area. Such advance notice allows PG&E to map any gas lines. In this case, the line had been marked earlier with two signs that were about 100 feet in each direction from where the county employee was working, PG&E spokesman Greg Snapper said.
PG&E wasn't notified about the work near the gas line because someone thought the driver would be working in a different area, Fresno County Public Works Director Alan Weaver told the Fresno Bee (http://bit.ly/1DpqiMh).
Weaver said he had not had a chance to talk to the driver, who was among the critically injured victims, but all of the department's heavy equipment operators are trained on how to navigate utility lines.