Chevron says hole in pipeline that leaked oil into Salt Lake City creek was size of a quarter

Chevron: Oil in Utah leaked from quarter-size hole

SALT LAKE CITY — Chevron Corp. said Monday it believes an electrical arc from a power line torched a quarter-size hole in a pipeline that spilled thousands of gallons of crude oil into a Salt Lake City creek over the weekend.

Rocky Mountain Power said the chain of events began with a tree limb that fell onto a power line late Friday, but the utility said it would be highly unusual for an arc to drill a hole in a buried pipeline by traveling through a metal fence post.

Chevron officials said the fence post was anchored within inches of the 3-foot-deep pipeline and could have acted like an electric torch, puncturing a hole in the pipe’s metal casing.

“We think of this as a one-in-a-million event,” Mark Sullivan, manager of Chevron’s oil refinery, said Monday at an oil-coated city pond. He said the systems in place for detecting pipeline leaks never imagined “this very unusual circumstance.”

Sullivan said Chevron estimates that 33,000 gallons of crude spilled into Red Butte Creek through the heart of Salt Lake City, about 50 percent more than the figure previously offered by the Salt Lake City Fire Department. But the company doesn’t know when the leak started.

The shorting of the power line that Chevron blames for causing the arc occurred at 9:19 p.m. Friday, but Chevron says it wasn’t notified of the spill for about another nine hours, until 6:52 a.m. Saturday.

It wasn’t until Sunday morning that residual amounts of oil stopped leaking from the ruptured pipeline, Sullivan said.

Much of the crude was collected from a pond in a city park where it coated Canada geese and ducks. It also suffocated trout in Red Butte Creek, according to residents.

State conservation officer Mike Roach said an adult goose, one gosling and eight ducklings died from oil ingestion. Hogle Zoo received 280 waterfowl for a scrubbing with corn oil, then Dawn detergent and a rinse.

“The birds had to be washed three times to get all the oil off, and each cleaning took an hour,” zoo spokesman Brad Parkin said Monday. “One bird had to be washed 15 times.”

The creek drains into Jordan River and, eventually, Great Salt Lake, but Sullivan said tests show no oil has reached the lake, a crucial migratory stop for bird species that feast on the lake’s freshwater margins.

Adding to the unlikely circumstances of the leak was the size of the hole in the pipeline that brings crude from the oil fields of western Colorado and eastern Utah.

“I was really surprised to hear this was a quarter-size hole,” Salt Lake City Mayor Ralph Becker said Monday.

Chevron officials said the pipeline was pressurized and could have spewed 33,000 gallons through the small hole before the leak was stopped.

Rocky Mountain Power spokesman David Eskelsen confirmed that a 40-minute power outage originated at the leak site but said the utility wasn’t certain that could set off a chain of events that resulted in the oil spill.

“There’s no scenario we understand that would produce the kind of damage that was suffered,” he said.

Eskelsen confirmed that Rocky Mountain Power owns the fence that Chevron says acted like an electric torch and guards a spot where overhead power lines dip underground. Chevron said no fence post should have been anchored within inches of a crude oil pipeline.

“It’s been there for about 30 years,” Eskelsen said Monday. “The theory of an electrical arc going through one of the those fence posts is plausible but we don’t have enough information to confirm it. We’ll be looking into it. If it does bear out, that would be unusual in the extreme.”

He added, “We’ll continue to work with Chevron on their inquiry. We recognize it’s been a terrible experience for the city.”

Chevron spokesman Dan Johnson planned to take reporters to the origin of the leak, but reporters didn’t get closer than about 50 yards. Johnson said the tour was overruled by Chevron superiors or fire officials as a safety risk.

(This version CORRECTS that volume of spill is 50 percent more than previously reported, not twice as much.)