Citing 9,205 Suncor air pollution violations in five years and inadequate enforcement by state and federal regulators, a coalition of environmental groups Wednesday filed notice of intent to sue the Commerce City refinery as a citizen-led action under the federal Clean Air Act.
Suncor’s pollution incidents continue despite state health department claims of achieving “record” financial settlements over past violations, said Earthjustice attorney Ian Coghill, leading a coalition that includes the Sierra Club, 350 Colorado and GreenLatinos that will sue the refinery in Denver’s federal district court.
Colorado’s most recent “record” fine against Suncor included only $2.5 million in financial penalties, when the cited violations called for up to $32 million in fines, Coghill said. That settlement included violations more than four years old, and machinery upgrades required in the recent settlements have themselves failed and caused pollution, he added.
“Whatever the state is doing has not stopped Suncor from continuing its same history of these chronic exceedances,” Coghill said, in detailing the 39-page notice of intent to sue. “What enforcement is supposed to be about is bringing sources into compliance and deterring future violations, and what the state has done thus far clearly hasn’t been sufficient.”
The lawsuit will effectively ask the courts to let the citizen groups take over from the state and the EPA in enforcing the Clean Air Act in Colorado. While provisions of the act allow for attorney’s fees if the citizens win their suit, any judgment against Suncor would go to the federal treasury and not to the environmental groups.
“We have documented 9,205 days of violations of regulations, consent decrees and permit provisions by Suncor in the past five years,” the notice of intent says. “Suncor’s violations threaten the health of the community groups’ members who are routinely exposed to the polluted air emitted from the refinery.”
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The broad action over past violations will play out as some of the same environmental watchdogs and community groups also attack state decisions on permits for how Suncor operates now and in the future. Colorado in late May issued a renewed permit for Suncor plants 1 and 3, which regulators say takes tough new monitoring and training measures but which opponents say they will challenge. There are also ongoing challenges to a renewed permit for Suncor’s plant 2, parts of which the EPA objected to and environmental groups continue to petition against.
Suncor’s primary pollutants
The notice of a lawsuit issued Wednesday charges Suncor with a litany of excess air pollutants, including:
- Hydrogen sulfide
- Sulfur dioxide
- “Opacity” or smoke and vapor emissions containing dangerous particulate matter
- Carbon monoxide
- Nitrogen oxides
- Flaring failures that released volatile organic compounds meant to be burned up. VOCs contribute to the northern Front Range ozone violations.
“Evidence suggests that these violations are both ongoing and recurring, and almost certain to recur in the future absent intervention,” the lawsuit notice says.
The notice of lawsuit includes in-depth research on the disproportionate impact of pollution on the communities surrounding Suncor, home to nearly 70,000 people. The neighborhoods in Commerce City, Globeville, Elyria-Swansea and elsewhere are 72% people of color and 37% economically disadvantaged, the notice says.
The neighborhoods rank in the 90th-plus percentiles for threats from particulate matter, airborne toxins, diesel particles and lead paint, among others. They also report among the highest incidence of pollution-related illnesses like asthma, heart disease and diabetes. While the neighborhoods have historically been inundated by pollution from metal smelters, stockyards, power plants and the busiest highways in Colorado, the lawsuit attributes significant responsibility to the big refinery.
Many of Suncor’s pollutants stem from the nature of its crude oil processing in Commerce City, Coghill said. When the refinery starts breaking down crude oil through catalytic cracking and other processes, it produces gasoline and jet fuel, but also substances called “refinery gas” that contain more sulfur than natural gas straight from a wellhead.

Like many refineries, Suncor uses the byproduct gas as fuel for its own boilers and machinery rather than purchasing natural gas from outside, Coghill said. If that refinery gas is not treated properly because of equipment failures or aging equipment, sulfur and other pollutants can hit the neighborhood.
The environmental groups are moving forward against Suncor on multiple fronts because writing strong permits for corporations is only one step, and Colorado has failed in the followup, Coghill said.
“The purpose of enforcement is making complying with your permit cheaper and better than violating the permit,” he said.
This story will be updated Wednesday with comments from Suncor and state regulators.
