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A bicyclist rolls west along the Sand Creek Regional Greenway past the Suncor refinery in Commerce City on Sand Creek on Wednesday, May 26, 2021. (Andy Colwell, Special to The Colorado Sun)

Suncor refinery officials say their testing after outflows of PFAS “forever chemicals” spiked from the site in November did not show any higher than normal contamination downstream on Sand Creek or in the South Platte River nearby. 

State regulators who responded to Suncor’s high test results beginning in November backed Suncor’s assertion about river water quality. But the state also said PFAS levels from Suncor outflows in December and January “remained above the effluent limits proposed” in a draft under consideration for the refinery’s renewed water quality permit. 

Environmental groups and neighbors want the state’s permit renewal to go even further than that current draft, ratcheting down PFAS allowances to the hundredths or thousandths of parts per trillion recently announced by the EPA as the new drinking water limit. Until now, the state has never required Suncor to limit PFAS running off the refinery, which for decades used firefighting foam containing the chemicals.

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Earthjustice, which first highlighted the high PFAS results, said Monday neither the state water quality division’s response “nor Suncor’s response explain what caused the spike in Suncor’s PFAS levels in November 2022. Although the division’s response at least provides some explanation of what didn’t cause the spike, we’re still left with best guesses on what did,” the nonprofit group said. 

The Earthjustice analysis of Suncor’s monthly filings with the state found November readings at 1,100 parts per trillion of one variant, PFOS, in discharges, or 55,000 times the tightened EPA requirements announced in March. Discharges of 54 parts per trillion of another variant, PFOA, that month were 13,500 times the new EPA limits on that chemical, Earthjustice said. 

The high discharges remained in January, though not as elevated. The February report showed lower levels. 

Suncor in a statement acknowledged the high November reading, but added: “It is not representative. Sampling results downstream of Suncor’s outfall taken on the same day do not show an increase in PFAS concentrations,” and in fact were lower than above Suncor on Sand Creek. Since 2019, Suncor said, its testing has shown levels upstream of the Commerce City refinery of PFOS and PFOA above the 70 parts per trillion that was the EPA guideline until March, and which is still the guideline in the state draft permit. 

Suncor’s statement said a sampling study by an independent firm in May 2022 said “Suncor’s PFAS contributions are not impacting the South Platte River in any meaningful way.” 

Earthjustice said Suncor’s own analysis in fact does show the company contributing significant amounts of the PFAS measured in the South Platte River, closely matching a report by a company hired by environmental groups. 

The Forever Problem: “Forever chemicals,” also known as PFAS, are an increasing toxic burden on Colorado and the United States, and The Colorado Sun is committed to coverage of public health threats posed by the ubiquitous consumer chemicals. We continue to follow threats from the chemicals to drinking water, croplands and wildlife, and the extensive costs required to clean them up.

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Suncor’s own report found the company’s discharges after installing its treatment system “accounted for approximately 16% and 2% of the ‘PFAS Compounds of Interest’ in Sand Creek and the South Platte River, respectively. Those amounts align with the low end of the range” in the report commissioned by the environmental groups, Earthjustice attorney Caitlin Miller said.

“Suncor may not be the only contributor to PFAS pollution in Sand Creek or the South Platte River, but there is no doubt that it’s a significant contributor,” Miller said. “The existence of other pollution sources does not excuse Suncor from complying with the Clean Water Act and the Colorado Water Quality Control Act, and the (state) must enforce the requirements of those laws to protect downstream communities.”

Moreover, Earthjustice said, water reports filed with the state by Suncor show ongoing spills of other substances, including four instances since Jan. 1 that include exceedances of state-permitted levels of benzene on six separate days.

Colorado regulators say they are still considering whether to further limit Suncor’s PFAS allowances before issuing another draft of the company’s renewed water quality permit. The EPA’s sharply revised caps are one thing under consideration, the state said. Any further revisions will be put out again for public comment, water quality division spokesperson Kaitlyn Beekman said. 

Suncor said that in October 2021, it voluntarily installed a temporary wastewater treatment to reduce PFOA and PFOS below the EPA’s then-current guidelines of 70 parts per trillion. The company noted that at the time, its water quality permit had no PFAS limits. The refinery is also studying two other PFAS reduction methods. 

The firefighting foam used at Suncor no longer contains PFOA or PFOS, the two variants of PFAS that were severely restricted by the March EPA revisions, according to the company. 

Michael Booth

Michael Booth is a Colorado Sun reporter covering health, health policy and the environment. Email: Twitter: @MBoothDenver