“Forever chemicals” flowing from Suncor into Sand Creek spike as Colorado weighs renewal of key water-quality permit
Environmentalists call on state to stop allowing Commerce City refinery to discharge PFAS chemicals into waterways
By NOELLE PHILLIPS | This email address is being protected from spambots. You need JavaScript enabled to view it. | The Denver Post
PUBLISHED: July 27, 2023 at 6:00 a.m. | UPDATED: July 27, 2023 at 10:36 a.m.
COMMERCE CITY — Along the Sand Creek Regional Greenway outside the Suncor Energy oil refinery, a single pipe spills water over a rock pile into Sand Creek, where it ripples and swirls before flowing through the stream toward the South Platte River.
Egrets fly past looking for their next meal as butterflies flit over the brushy banks. If you’re not looking for it, the 24-inch-wide pipe is easy to miss underneath the vines and branches draping over its edges.
But more than 3 million gallons of water a day flow from that pipe — known officially as Outfall 20 — and mixed in that water are poisonous chemicals that pour downstream to where Sand Creek merges with the South Platte River, the source of drinking water for hundreds of thousands of people in Colorado and an important supply for agriculture in the northeastern part of the state.
There are 10 locations around Suncor’s 3.4-mile perimeter in Commerce City where wastewater and stormwater are released into the community, but Outfall 20 on the banks of Sand Creek is the main discharge point. Pollutants released into the creek include per- and polyfluoroalkyl substances — also known as PFAS, or “forever chemicals” — as well as benzene, arsenic and dozens of other chemicals, many of them proprietary to Suncor’s refining process.
Suncor receives intense scrutiny for its air pollution, frequently sending public alerts about excessive emissions that can make people sick. But the refinery also pollutes the water. Over the years, Suncor repeatedly has discharged more pollutants into Sand Creek than its state-issued water-quality permit allows, sometimes causing an oily sheen to blanket the creek.
Now, the Colorado Department of Public Health and Environment is poised to approve a new, and overdue, water permit for Suncor that will regulate how much pollution it pours into Sand Creek over the next five years. A decision on the permit is expected sometime this year, although state officials say there is no hard deadline for its approval.
Meanwhile, the permitting process has taken so long that, midstream, the Environmental Protection Agency changed its recommendations on how much toxic PFAS can be discharged into rivers and streams. That led environmentalists and local government water managers to ask the state to reconsider the permit even as recent monitoring reports show Suncor is pumping forever chemicals into Sand Creek at rates up to 38 times higher than limits proposed in the new permit.
The permit renewal also comes as the refinery is under increasing pressure to clean up its property and the air and water around it, with people demanding better environmental stewardship in the surrounding neighborhoods, which are predominantly Latino and Indigenous communities.
Last month, the state health department’s Water Quality Control Division sent a compliance advisory to Donald Austin, the vice president who oversees Suncor’s Commerce City operations, to serve notice that the company is under investigation for violating the Colorado Water Quality Control Act because of multiple benzene spills earlier this year.
“Due to the severity and/or persistence of these violations, the Water Quality Control Division is initiating a process to determine whether a formal enforcement action is warranted,” the letter stated.
Environmentalists who monitor pollution coming from Suncor say that letter is exactly why they are pushing the state to place stricter conditions, including lower limits for pollutants and increased testing, in Suncor’s next water permit.
“Something has to be done,” said Caitlin Miller, a senior associate attorney with Earthjustice’s Rocky Mountain office. “We need a strong permit in place and then we need the division to enforce it. Something definitely has to be done.”
A Suncor spokeswoman, Loa Esquilin Garcia, told The Denver Post the company would not comment on the water permit or pollution problems because the company recently experienced a cybersecurity breach. But Suncor’s legal team has objected to multiple proposals in the state’s draft permit on the grounds that they would be expensive to implement, are unnecessary and arbitrary, or do not fall within the state’s specific water regulations.
Officials at the Colorado Department of Public Health and Environment declined an interview request from The Post to discuss the permit, saying they would “wait to do interviews on this until we have made some final decisions on what’s next for the permit,” according to an email from Kaitlyn Beekman, a spokeswoman for the Water Quality Control Division.
The agency did provide The Post with some written responses to general questions about the permit.
What the new permit would do
Suncor’s proposed water permit has been under consideration for nearly two years as the state consolidates two permits — one for wastewater, or process water, and one for stormwater — into a single permit. Those two permits were last updated in 2012.
The state health department has said it would finalize the permit in mid-2023, although officials would not commit to a hard timeline. The EPA expects water permits to be renewed every five to seven years, according to a written response to The Post’s inquiries from Trisha Oeth, Colorado’s director of environmental health and protection.
That means the state is behind schedule, so Suncor continues to operate under its 2012 permits.
Once the state finalizes the new permit, it will be sent to the EPA for approval. The EPA then has 90 days to object or accept it.
The wastewater permit covers the water used to refine petroleum into gasoline and other fuels, which is discharged into Sand Creek, while the stormwater permit regulates what runs off Suncor’s property into sewer systems and creeks after rain or snow.
The new permit proposes to reclassify some stormwater pipes as wastewater outfalls after EPA inspections found Suncor was illegally releasing chemicals used in the refining process through those pipes. The change would cause those former stormwater pipes to be regulated much like Outfall 20, the main discharge point, according to a state health department presentation on the proposed permit.
The proposed permit would include other major changes that the state’s Water Quality Control Division believes will protect drinking water, fish and groundwater:
•Limit PFAS levels to meet EPA guidelines for how much of these chemicals can be released into Sand Creek
•Set new limits for dangerous organic chemicals related to petroleum refining and require monitoring for those chemicals
•Set new limits and monitoring on aluminum, cadmium, chromium and iron, which are metals that can harm fish
•Test for certain chemicals in Sand Creek monthly instead of quarterly
•Set new limits for 41 commercial chemicals used in the refining process that were not previously regulated
•Set new limits for benzene, toluene, ethylbenzene and xylene in the stormwater outfalls
•Require Suncor to use a special camera to inspect and map all pipes and conduits, including abandoned pipes
•Require Suncor to create a maintenance schedule for all of its water treatment equipment so it is repaired and replaced when needed
•Require Suncor to line the Burlington Ditch, a canal on its western border, if it cannot prove that contaminated groundwater has not leaked into the ditch.
•Require Suncor to send public notifications on water pollution through its existing text and email alert systems
•Trigger a permit modification if the Water Quality Control Commissions decides a section of the South Platte River needs special protections
Overall, the proposed permit shows positive momentum toward reducing Suncor’s water pollution, especially when it comes to addressing PFAS, said Sonya Lunder, senior toxics policy advisor for the Sierra Club. The draft permit is one of the first in the nation that is addressing PFAS discharged by a refinery, she said.
But it’s understandable that people who live near the refinery and are most impacted by its pollution feel like it’s taking too long.
“For people who live in these polluted communities, the idea that they are going to spend three years making a water permit doesn’t feel proportional to the challenge of living there every day,” Lunder said.

The PFAS problem
Forever chemicals are the most pressing issue swirling around the Suncor water-quality permit.
Because those chemicals do not break down, they accumulate in the human body when people drink water or eat food contaminated by them. While the scientific understanding of these chemicals is rapidly advancing, the EPA says they can lower women’s fertility, lead to developmental delays in children and cause cancer in the kidneys, prostate and testicles, among other health problems.
Sand Creek was identified in 2019 as one of multiple PFAS hotspots in Colorado by state environmental officials, and forever chemicals are a growing concern across the United States. Multiple hotspots, including those in Colorado Springs and in Aurora, are near U.S. Air Force bases that for years used firefighting foams that contain the chemicals.
The refinery also uses firefighting foam that contains multiple compounds that are considered to be PFAS, an umbrella for multiple compounds that do not break down and dissolve. Those chemicals have contaminated groundwater underneath the refinery’s property, and Suncor treats that groundwater before releasing it into Sand Creek.
Still, those forever chemicals get into the water.
Suncor’s most recent monitoring data from June shows the company discharged one PFAS compound — PFOS — at 2,500 parts per trillion. The EPA’s most recent health advisory for that compound said it should be detected at levels no higher than 0.02 parts per trillion.
And the company’s total combined discharge for all PFAS compounds in June reached 2,675 part per trillion, according to data Suncor submitted to the state on July 17. That’s 38 times the proposed limit of 70 parts per trillion for all PFAS chemicals.
Suncor’s report said the company did not have an explanation for why PFAS levels spiked last month, but it was investigating the cause. Company officials did not respond to an email from The Post that asked about the June report.
Ean Tafoya, executive director of GreenLatinos Colorado, said the most recent PFAS report for Suncor was alarming.
“What is going on over there?” Tafoya said. “I saw the numbers and it scared me. Did they have a fire they didn’t tell us about? Was there a spill
The EPA changed its guidelines for what is considered an acceptable amount of PFAS in water during the current permitting process, so multiple organizations, including Earthjustice and GreenLatinos, asked the state health department to reopen public comment on the draft permit in light of those new recommendations.
When the last Suncor water-quality permits were issued 11 years ago, no guidelines existed on how to regulate PFAS flowing into the water or soil. The EPA issued health advisory levels for PFAS in 2016 and Colorado adopted those standards in 2020, which would allow Suncor to release the forever chemicals at 70 parts per trillion into Sand Creek.
However, since the draft permit was written, the EPA released a new health advisory that says negative health effects can occur even when PFAS levels are near zero. Now, environmentalists want Colorado’s water regulators to make Suncor’s next water permit reflect that advisory.
The water division should set the acceptable levels of PFAS to non-detectable, Earthjustice’s Miller said, meaning that anyone testing the water would not be able to find evidence of those chemicals.
“Everything we know about PFAS and everything we’ve learned over the last year is these are highly toxic chemicals,” Miller said.
But the state health department has not reopened the permitting process, nor will its leaders say how the agency will address Suncor’s PFAS levels in the next permit.
The EPA’s recommendations are considered an advisory for states rather than an enforceable regulation, said Oeth, with the state health department. So in the absence of federal rules, the state set PFAS limits for Suncor based on the 70 parts per trillion advisory issued in 2016.
Suncor is unreliable when it comes to controlling the pollution it pours into Sand Creek, Earthjustice’s Miller said.
Suncor’s June spike in PFAS is not an isolated incident.
The company’s reporting shows that it exceeded 70 parts per trillion four times in the 12 months between May 2022 and May 2023, according to data compiled by Earthjustice.
Some of those spikes, such as the one, in June have been massive.
In May, the company reported that it discharged 218 parts per trillion of PFAS compounds into Sand Creek, according to a report filed with the Water Quality Control Division. That’s more than three times higher than what the draft permit for Suncor would allow.
And in November, the refinery reported discharging 1,100 parts per trillion of PFAS into the creek — 15 times higher than what the permit would a
Suncor says it is making changes to control its PFAS discharges, including changing its firefighting foam to eliminate at least two toxic compounds — PFOS and PFOA.
In a Feb. 17, 2022, letter to the health department about the draft permit, Gabe Racz, a water lawyer with the Boulder firm Vranesh and Raisch, wrote that Suncor had installed an interim water treatment system to voluntarily reduce its PFAS discharge to the EPA’s recommended amount of 70 parts per trillion.
The company estimated it would take three years and millions of dollars to build a permanent system to treat wastewater for PFAS before discharging it into Sand Creek, the letter said.
“Further PFAS are extremely difficult to treat for and technologies to be able to reduce PFAS are still in development,” Racz wrote in the letter. “Additionally, disposal of PFAS treatment residuals is very limited with most landfills not accepting PFAS waste. These factors mean it will require time and thoughtful design of treatment processes if the end result is to ‘break the chain’ of PFAS exposures.”
Because company officials declined to be interviewed about the permit, it’s not known whether Suncor would be able to comply with a requirement to lower its PFAS discharges into Sand Creek to an undetectable level.
But the company is under increasing pressure from the state’s water division to clean up its property and keep PFAS out of Sand Creek.
The state health department has required increased testing, including in groundwater wells on site and in waterways adjacent to its property. The state also ordered Suncor to replace or repair a barrier wall on its northern boundary to keep PFAS from discharging directly into Sand Creek, Oeth’s emailed statement said.
Two areas on Suncor’s property have been identified as sources for PFAS contamination and the company is supposed to be remediating those sites, Oeth said.
“These sites are contaminated soils that will be remediated to ensure protection of human health and environment,” Oeth’s statement said. “These release PFOA and PFOS to the groundwater, acting as a continuous source of contamination to the environment. Remediation will likely involve removal of PFAS contaminated soils.”
Martin Kimmes, Thornton’s water treatment and quality manager, said the city also has asked the state health department to reopen the permit discussions about recommended PFAS levels.
But he doesn’t know how the state plans to handle the new guidelines.
Thornton’s 160,000 water customers do not want to drink water contaminated with PFAS, something that the city already struggles with.
“We’d love to see no PFAS being pumped out of Suncor because the health advisory says pretty much it should be zero,” Kimmes said. “Our water customers aren’t going to be satisfied because of the health risks A portion of Thornton’s drinking water is pulled from Sand Creek upstream of the Suncor refinery and then diverted into the Burlington Ditch, a canal that runs between Suncor’s western border and Metro Water Recovery, Denver’s primary wastewater treatment plant.
Suncor is not allowed to discharge any wastewater into the ditch, but over the years the refinery’s leaks have seeped into the canal, which provides water to Thornton, Commerce City, and ranches and farms in the northeastern part of Colorado.
That’s why the draft permit proposes that Suncor line the ditch to prevent its contaminated groundwater from reaching drinking water. Thornton supports that proposal, even though the city does not have evidence that Suncor contributes to its PFAS problem, Kimmes said.
“We know the potential is there and that’s why we would like to see it lined,” Kimmes said.
Suncor objected to the lining in its February 2022 letter to the health department. Lining the ditch would cost millions of dollars, and there’s no evidence that any water quality improvements would be gained, Racz, Suncor’s water lawyer, wrote.
Racz’s letter also said Suncor objected to a proposed requirement that would force the company to pay for a special study to determine if any pollutants are seeping into the canal.
However, Curt Bauers, a Denver-based water consultant who formerly served on the Burlington Ditch’s board of directors, said the lining is necessary because Suncor’s groundwater pollution seeps into the canal.
A plume of contaminated groundwater under Suncor’s property is well documented and that groundwater, which contains benzene and other chemicals, seeps into surrounding areas.
When the canal is full, there is less risk of Suncor’s contaminated groundwater leaking into the canal because of downward pressure. But it’s well documented that the pollution does get into canal when water levels are low or the canal is empty, Bauers said.
“It’s an environmental trespass if your contamination ends up on my property,” Bauers said.
Pouring a concrete barrier along the Burlington Ditch where it borders Suncor would be a solution, he said.
“The idea is if the ditch is lined they will be forever separated from the water we are diverting from the river,” Bauers said.
A concrete barrier, however, would not stop all of the Suncor contamination that reaches the Burlington Ditch.
Suncor is not permitted to discharge any water into the ditch. But as recently as May 12, the refinery reported that its stormwater containment system had failed during a storm and water had flowed into the ditch. Some water escaped through a crack in a barrier and more overflowed a containment wall, according to a report Suncor filed with the Water Quality Control Division.
Water tests in the ditch detected benzene.
A Suncor official wrote in the report that benzene levels were recorded at 0.18 micrograms per liter and noted that Suncor is permitted to release benzene at 5 micrograms per liter. But that permit is for Outfall 20 on Sand Creek, not the Burlington Ditch.
Environmentalists also are concerned about a group of pollutants known as BTEX — benzene, toluene, ethylbenze and xylene — that are associated with oil refining.
Over the years, benzene has been one of the most problematic pollutants for the waterways around Suncor. The chemical evaporates in sunlight, but in large amounts, it’s a major health concern.
Benzene is a highly carcinogenic pollutant associated with petroleum products. Short-term exposure can make people feel sick with symptoms such as dizziness, headaches and respiratory irritation. Long-term exposure can cause leukemia and other blood disorders as well as harm a woman’s reproductive system.
“The limits of benzene that you can drink or inhale before you have health problems are very, very low,” Lunder said.
In 2011, a Suncor spill caused benzene levels in Sand Creek to exceed national safety standards by more than 100 times recommended levels. It took nearly two years to clean it up.
More recently, Suncor has reported five benzene spills in 2023 into Sand Creek, although those discharges haven’t been as severe as the 2011 incident.
Under Suncor’s existing permit, the refinery is allowed to discharge a daily maximum of 5 micrograms per liter of benzene. The 2023 spills happened on Jan. 4, 5, 25, 26 and 28 and recorded levels that ranged from 6 micrograms per liter to 13 micrograms per liter, according to an analysis by The Post of reports filed with the Water Quality Control Division.
A sixth spill on Feb. 1 did not cause the refinery to exceed its benzene discharge limits.
Those spills came amid a three-month shutdown at the refinery after a December deep freeze damaged equipment.
Refinery officials blamed the Jan. 4 and 5 spills on a late-December fire that also injured two workers. Benzene leaked into the company’s stormwater system after the fire, according to the company’s spill reports.
Other spill reports did not list the cause, but they all took place after the refinery shut down.
That series of spills triggered state health officials to fire off a compliance advisory letter to Suncor, warning that reports indicate “significant noncompliance” and enforcement action could be coming.
In spite of those spills, the new draft permit would not change the amount of benzene the company is permitted to release into Sand Creek.
Too precious to pollute
One reason the new permit is so important is because Suncor is one of a handful of refineries in the United States that does not discharge its pollutants into the ocean. Instead, it pours wastewater into a stream, the Sierra Club’s Lunder said.
“Unlike drops of benzene in the ocean, which isn’t great, this flows directly through to communities and through irrigation to agricultural communities,” she said. “It has a big impact on the river.”
It is critical that water be clean, especially in the drought-stricken West, where it is a precious commodity.
“We can’t just be so cavalier about our water sources,” Lunder said.
When GreenLatinos surveys residents about their environmental concerns, they say drinking water quality is extremely important to them, Tafoya said.
“A lot of the focus on water in the media is around quantity and very last on quality,” he said. “But so many communities say they don’t trust their water, and it comes back to funding.”
And as the West continues to dry, communities can’t afford to abandon water sources because they are polluted, Lunder said.
It’s expensive to remove PFAS from waterways, so the Sierra Club would prefer Suncor be forced to clean up its dirty water and soil rather than forcing communities downstream such as Thornton to pay for it.
“We have a real problem, once PFAS enter the environment, of keeping them out of the fish we eat and the food we eat,” Lunder said. “We’re really focused on ending the use of these chemicals and cleaning up polluted sites instead of chasing our tail and finding it downstream and choosing really expensive options for cleaning it up.”