SALT LAKE CITY — More than two years after 33,600 gallons of Chevron oil spilled into Red Butte Creek, state water quality regulators are declaring the creek as clean as other Salt Lake urban creeks unaffected by the spill.
A draft public health and ecological risk assessment of the riparian waterway released Thursday, however, does not necessarily mean the state Division of Water Quality and other agencies are ready to close the door on future cleanup efforts.
"We want to make sure this assessment stands up to scientific muster and if there is something that tells us there is something else we should do," said the division's Chris Bittner, an environmental toxicologist. "This has an effect on the public and the public should have a say."
The assessment is making the rounds at Salt Lake City and the Salt Lake Valley Health Department, the division's main partners in the cleanup of the creek that runs in the northeast part of Salt Lake County. Public comment is being accepted through Aug. 13.
Comments may be submitted by email to firstname.lastname@example.org or in writing to Division of Water Quality (Attn. Chris Bittner), 195 N. 1950 W., Salt Lake City, UT 84114-4870.
Overall, the division believes the cleanup has left Red Butte Creek safe for regular use by local residents and that any residue that remains does not pose a threat to people or pets.
Both Bittner and John Whitehead, assistant water quality director, said no decisions are contained in the document and they are aware that some residents maintain that the creek remains despoiled.
"Even if it were spotless," there would be some skepticism, Whitehead acknowledged.
A March lawsuit filed against Chevron contends a group of more than 60 plaintiffs — many of them residents in upscale neighborhoods adjacent to the creek — believe residual oil from the spill continues to cause them health problems. The crude oil remnants they contend remain from the June 2010 spill contain carcinogenic compounds that pose health risks.
The angst over what does or does not remain in the creek continues to plague the division more than two years after a lightning storm toppled a tree into an overhead power line above Red Butte Gardens. A resulting electrical arc traveled down a metal fence post and ruptured the pipe buried 3 feet underground.
A hole the size of a quarter allowed 800 barrels of oil to ooze undetected for some 10 hours into the creek and downstream to the lake at Liberty Pond. Some of the oil was ferried to the Jordan River, a stretch of which had to be closed for public health reasons.
Less than six months later, Chevron experienced another spill in the same pipe upstream from the first spill — but none of that oil made it into the waterway.
In the aftermath, Chevron was fined by the federal government and paid out $1 million to Salt Lake City for lost use of the stream. The company paid another $500,000 to the state in penalties, paid $3 million in mitigation projects and reimbursed residents and others affected with $929,000 in payments.
Last year, Chevron estimated its actual cleanup costs to date were $75 million; the company said it would continue its remediation efforts until state, health and city officials accept the cleanup as completed.
Whitehead said quarterly tests done by the state and more than 300 samples taken by Chevron but independently confirmed by the division show trace amounts of oil-related compounds remain in Red Butte Creek.
Those same compounds, however, are present in similar levels in samples pulled from other urban waterways such as City Creek, Emigration Creek, Parleys and Millcreek, Bittner said.
The amounts in Red Butte are not a significantly large enough sample to provide an identifiable crude oil "marker" that would tell the water quality division that the compounds, indeed, came from Chevron oil, Bittner said.
"We will never know because it is similar to what we find in other creeks," Bittner said. "If I came in blind and did not know there had been an oil spill in Red Butte Creek, I would not think there had been a spill in Red Butte Creek."
Bittner said the same hydrocarbon compounds are present in a sample taken from a site in the creek above the spill location near Red Butte Gardens.
The division must consider "how clean is clean" given that no sampling of water quality exists prior to the spill, Bittner said.
"We will never know because we don't what was in Red Butte Creek prior to the spill."
Bittner and Whitehead said urban runoff — oil residue being washed by the rain into a creek from a nearby parking lot or a car leaking oil driving past a storm drain grate — fuel the constant presence of hydrocarbon compounds in the urban waterways.
If what is being detected in Red Butte came from Chevron, Bittner said he suspects the levels of compounds would continue to decrease, rather than remain constant like they are.
Whitehead said a better barometer of the creek's health is evidenced by the presence of aquatic organisms, which were wiped out by the spill. Sampling shows that the organisms are recovering, but have not caught up to levels seen above the spill site.
While it may be possible to completely remove any residue by digging up the creek, Whitehead such an action would disturb what progress has been made by the aquatic life in the last two years, and the contamination would simply return due to urban runoff.