How clean is clean enough?
It's been a nagging question for the two years since an oil pipeline in the Salt Lake City foothills sprung a leak, spewing thousands of gallons of stinky, gooey petroleum down Red Butte Creek, through upscale east-side neighborhoods and into a Liberty Park pond-turned-catchment.
Now, after $43 million in cleanup along with innumerable water, soil and air tests state environmental officials believe they can answer the question.
In essence, they say, the spill site may be about as clean as it's going to get.
The Utah Division of Water Quality is inviting the public to double-check its findings before issuing its final decision and perhaps sending the cleanup crews home.
"What we need to do is make a good public policy decision based on sound science," said John Whitehead, the agency's assistant director. "This is the information we need to help make the decision."
On Thursday, the agency is releasing its assessment of the lingering health and environmental impacts along the nearly three miles affected by the June 2010 spill and a second one six months later. Total crude lost: 54,600 gallons.
Houston-based Chevron Pipe Line Co. has spent about $43 million the past two years scrubbing oil from creek beds, parks and backyards beginning at Red Butte Garden and ending below the Liberty Park pond. The money also has compensated affected residents, paid penalties to government agencies and covered reimbursements for environmental damage.
In its draft assessment, state water crews checked more than a dozen locations along the creek at least a half-dozen times for key components of petroleum, including cancer-causing benzene.
And, since they hadn't tested for those chemicals before the spill, the scientists used other nearby streams City Creek, Emigration, Mill Creek and Parleys for comparison.
Those creeks, like other urban waterways, often take in grease from streets, sidewalks, driveways and parking lots. In fact, petroleum markers were higher in Mill Creek which hadn't suffered a massive spill than they were in Red Butte Creek, according to the tests.
After the cleanup, said Chris Bittner, a toxicologist, "we find Red Butte Creek is statistically no different than those." They all have trace amounts of oil contamination.
To assess environmental impacts, water experts looked at stream plants, insects, fish, amphibians, reptiles, birds and mammals.
Bugs became their canaries in the coal mine. After eight rounds of sampling above and below the spill site, bugs of all types are rebounding, said Bittner, pointing to charts representing the number and variety of insects. "You can see they are coming back."
For its part, Chevron promised to continue working on the restoration.
"We believe that our cleanup efforts have successfully addressed the impacts from the spill," the company said in a statement.
Attorney Paul Durham, who represents 66 spill-affected residents suing Chevron, doubts the work is done. He said he has invited an independent health risk expert to evaluate the spill areas.
"There's still residue on the properties that hasn't been cleaned up yet," he said.
Noting that his case is moving forward on the premise that the hazard will exist as long as crude oil flows through the pipeline, he warned: "Of course, there could be more spills."
Salt Lake City resident Alyssa Kay whose young son, Darius, was in and out of the hospital for days after the spill still has "nagging concern in the back of her mind" that her boy's health has been changed forever because of his exposure to the fumes. Chevron paid to relocate her family from its home across the street from Liberty Park's pond, and she recently made a permanent move to Herriman.
"There was still no evidence to me it was safe," said Kay, whose son is now 6½. "At this point, I'm just trying to move on and get life back to normal."
Royal DeLegge, who oversees the environmental section of the Salt Lake Valley Health Department, said he doesn't expect his office to comment on the assessment.
"Just looking at the data, it's returned to what you'd expect an urban stream to be," he said. Any residual effects are bound to heal with time.
He noted that monitoring and spot cleaning will continue as did Renee Zollinger, Salt Lake City's point person on the spill.
She said residents should not be surprised to see Chevron crews continuing their restoration efforts through the summer and into next year. But whether to keep the cleanup going that's up to the Division of Water Quality after hearing from the public over the next 30 days.
"I can see, emotionally, there's a desire to keep scrubbing at something that's hurt you in the past," she said, adding that the science seems to show the area is as clean as it's going to get and that any more work might harm the environment.
"We will never be able to deal with all of the emotional scars that were caused by this," Whitehead said. "That's something that, unfortunately, will remain. Our charge is to make good public policy decisions on this cleanup. Ultimately, somebody has to say, 'Are we done yet?' We have to make that call."
About the 2010 spills
R Two leaks from a Chevron pipeline spilled 54,600 gallons of crude oil near Red Butte Garden in Salt Lake City's eastern foothills in 2010.
The June 11-12 spill unleashed 33,600 gallons of crude, scarring Red Butte Creek, the Liberty Park pond and parts of the Jordan River. The pipe was repaired and reopened little more than a week later on June 21.
A second spill, on Dec. 1, spewed 21,000 gallons near Red Butte Garden's amphitheater. The pipeline reopened Feb. 1, 2011, with safety upgrades. The Liberty Park pond, however, didn't reopen until May 14 that year.