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The Suncor refinery in Commerce City is pictured on Sand Creek from along the Sand Creek Regional Greenway on May 26, 2021. (Andy Colwell, Special to The Colorado Sun)

Discharges of water tainted with PFAS “forever chemicals” from the Suncor refinery spiked again in May, an environmental watchdog group said, following high readings in November and January. 

Suncor, which has used firefighting foam containing PFAS chemicals for years on the sprawling Commerce City property, reported May discharges into Sand Creek at 218 parts per trillion of variants of the  chemicals known as PFOS, PFOA and PFNA, according to Earthjustice attorneys. The group monitors Suncor’s required reporting to state water quality regulators. 

Immediately after leaving Suncor, the discharged water is carried by Sand Creek into the South Platte River as it flows through Adams County. The May discharge peaks were more than three times the PFAS limits proposed in a 2022 draft renewal permit written by state regulators to cover Suncor’s water discharges. 

The report shows Suncor’s “continuing inability to reliably treat their PFAS to meet even the division’s proposed 70 parts per trillion limit, and that limit is still way too high and based on outdated information,” Earthjustice attorney Caitlin Miller said. “Suncor’s continued failure negatively impacts Sand Creek and the South Platte River.” 

Neither Suncor nor state regulators responded to new questions about the high discharge readings from May. 

The thousands of variations of PFAS chemicals are used in countless consumer and industrial products for water and stain resistance, among other functions. They were used for decades in everything from carpet to firefighting products to clothing and fast-food packaging, though manufacturers are trying to phase them out of many products and states like Colorado are banning them. States’ attorney general offices, including Colorado, are suing manufacturers like 3M and DuPont to recover water filtration and ground cleanup costs. 

PFAS chemicals do not easily break down in the environment, thus the “forever” moniker, and have been found in fish, wildlife and in the bloodstream of most humans tested.

Until March, the EPA’s drinking water guideline — not a mandate to water agencies, but health guidance — had been limiting PFAS to 70 parts per trillion. Then the EPA issued sharply lower levels that are now drinking water mandates that cities must achieve, setting them as low as 0.02 parts per trillion for the variant PFOS, and 0.004 ppt for PFOA.

Earthjustice had previously flagged Suncor refinery releases of PFAS. One outflow measured at Suncor found November readings at 1,100 parts per trillion of PFOS in discharges, or 55,000 times the downward-revised EPA requirements. Discharges of 54 parts per trillion of PFOA that month were 13,500 times the new EPA limits on that chemical, Earthjustice said. 

The Forever Problem

“Forever chemicals,” or PFAS, are an increasing toxic burden on Colorado. We’re committed to covering the public health threats, from water and croplands to the costs to clean them up.

>> Find more coverage

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

The elevated discharges came as state clean water officials worked to complete revisions to Suncor’s water outflow pollution permits that were first opened to public comments nearly 18 months ago. Colorado officials noted at the time they had included PFAS limits for the first time in a draft of the revised permit.

Suncor had major December fires that prompted air pollution notices and a long shutdown of refining operations, and environmental groups monitoring pollution there speculate the firefighting foam commonly used in industrial fires could have contributed to more PFAS runoff. The refinery recently announced $100 million in repairs to reduce its air emissions. 

The state’s proposed draft permit revision for Suncor first revealed in 2022 set PFAS discharge limits at the same 70 parts per trillion that had been the EPA drinking water guideline until this year. In response to the high Suncor discharges in 2022 and early 2023, and the EPA’s March 2023 revisions, state regulators said they were reconsidering the draft permit. They have not offered a timetable on when those revisions will be put out for another public comment period. 

After Earthjustice called out their November and January PFAS releases, Suncor said the company’s testing away from the refinery outflow did not show any higher than normal contamination downstream on Sand Creek or in the South Platte River nearby. 

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 disputes that conclusion, saying a report from Westwater Hydrology at the “Outfall 20” in question “accounted for between 16-47% of total PFAS found in Sand Creek, and 3-18% of PFAS found in the South Platte River downstream of the facility.”

Michael Booth is The Sun’s environment writer, and co-author of The Sun’s weekly climate and health newsletter The Temperature. He and John Ingold host the weekly SunUp podcast on The Temperature topics every Thursday. He is co-author...