Aftermath of the S.L. oil spill: Did power line cause the break?

SALT LAKE CITY — At ground zero of the weekend's oil spill into Red Butte Creek, a welding crew is furiously at work, high-voltage power lines swinging overhead.

An extensive labyrinth of absorbent booms snakes across and alongside the creek, amid piles and piles of sandbags intended to help recapture and control the spread of 33,000 gallons of oil.

It is a scene of injury and repair that is in direct contradiction to a lush and blooming rose garden not far away.

At a news conference Monday, Chevron officials revised their estimate of how much oil was released in Saturday's pipeline leak and announced a remediation plan that carves out 18 sections of impacted areas targeted for extensive cleanup.

Mark Sullivan, manager of the company's Beck Street refinery, said the firm is also pursuing a theory on the cause of the pipeline's fracture, which he termed "a very unusual event" not experienced before.

The 10-inch-diameter pipeline that failed is in close proximity to a metal fence and overhead, high-voltage power lines.

Sullivan said an electrical arc might have been substantial enough to blow a hole in the line the size of a quarter.

While Sullivan said there are multiple safety systems in place designed to monitor the pipeline, they are designed to catch typical pipeline failures such as those caused by corrosion or other wear and tear.

Rocky Mountain Power spokesman Dave Eskelsen said a power outage did occur on Salt Lake City's east bench as a result of the storm Friday night.

Wind knocked a tree into a power line near a chain-link fence post not far from the pipeline breach.

"It was a fairly typical power outage for us but it did create an electrical fault," in which the current flowed into the tree, Eskelsen said.

"Their (Chevron's) theory is that there was an electrical arc that traveled down the fence post and into the pipeline. We don't have enough information to say if that was the cause, but we are working with them and are engaged in that process now," he said.

The chain-link fence topped with barbed wire was installed in the early 1980s and is at the juncture where overhead lines go underground, Eskelsen said.

Officials, in the meantime, are continuing to monitor the Jordan River, where an oil sheen has been detected at about 1800 North. So far, authorities say the oil has not made it the Great Salt Lake.