In a rare move, the Environmental Protection Agency announced Tuesday that it objects to one of Suncor Energy’s new air-quality permits and sent it back to Colorado environmental regulators to make changes that would further limit the pollution coming from the Commerce City refinery.

It’s the second time the EPA has rejected the Title V air permit for Suncor’s Plant 2, which is one of three plants on-site that refines oil into gasoline and other fuels. The objection does not mean the plant has to shut down, and Suncor can continue operating under its old permit until the new one is resolved.

The objection comes after multiple environmental groups, led by Earthjustice and 350 Colorado, filed petitions last fall asking the federal agency to reconsider the permit because it did not do enough to limit Suncor’s pollution.

The move will hold Suncor more accountable for its history of violations and strengthen the state and federal government’s ability to regulate its pollution in the future, said Ian Coghill, senior attorney with Earthjustice’s Rocky Mountain Office.

“Suncor is one of the biggest sources of pollution in the state,” Coghill said. “It’s smack dab in the middle of a residential area. People living around there have been dealing with what Suncor has been putting out for decades.”

Suncor representatives did not respond to an inquiry from The Denver Post about the EPA’s decision.

The Colorado Department of Public Health and Environment said no one on staff was available for an interview Tuesday, but spokeswoman Kate Malloy issued a statement saying the agency was reviewing the EPA’s decision and would work with those impacted to develop a stronger permit.

The EPA is directing the state health department to determine whether additional operational requirements are needed to make sure Suncor complies with limits on the emission of carbon monoxide and visible pollution such as smoke, sulfur and particulate matter from Plant 2’s fluid catalytic cracking unit, which is used to convert crude oil to petroleum products such as gasoline.

That unit has been a problem for years and consistently violates Suncor’s existing permit standards, Coghill said. The new permit could force the company to address those ongoing problems.

“This is a really big deal,” Coghill said.

The EPA also wants the state health department to revisit previous modifications made to equipment at the plant and determine whether new requirements should be put in place, the news release said.

In the past, the state did not require Suncor to get permits every time it performed maintenance or upgraded equipment at the plant. The state’s Air Pollution Control Division, which is under the health department’s oversight, previously has said it did not have the authority to review and approve those plans.

“The EPA flatly rejected that here,” Coghill said.

KC Becker, who leads the EPA’s Region 8 office, which covers Colorado, said the agency was putting a priority on improved air quality for those who live near the refinery.

“Improving air quality for the underserved communities affected by harmful air emissions from the Suncor refinery is a shared priority for EPA and CDPHE,” Becker said in a news release. “EPA will continue to work with Colorado to secure the refinery’s compliance with laws and regulations and protect the health of nearby residents.”

Environmentalists who were part of the coalition led by Earthjustice were pleased with the EPA’s ruling.

Ramesh Bhatt, chair of the Colorado Sierra Club Conservation Committee, said his group was glad the EPA is pushing state regulators to make permit conditions more stringent.

“Suncor’s rampant pollution has gone on for decades and the people in the area are suffering,” Bhatt said in an emailed statement. “This cannot continue. It is time for state and federal agencies to step in and force Suncor to clean up its act.”

350 Colorado, a group focused on reversing climate change, filed a separate petition from Earthjustice, but shared some of the same concerns, which are now being addressed.

But 350 Colorado asked the EPA to terminate Suncor’s permit, which would have forced the company to shutter Plant 2, said Heidi Leathwood, a climate policy analyst with the nonprofit that works to end the state’s reliance on fossil fuels.

“We think that Suncor has shown again and again they are not going to operate without all of those violations of their permits,” Leathwood said. “They’ve violated the Clean Air Act 12 out of the past 12 quarters and the Clean Water Act 10 out of the last 12 quarters. No matter what, we think, they prefer to pay the fines rather than stop violating the permit.”

U.S. Rep. Diana DeGette, D-Denver, said in a news release that she would like to see regulators go even further to bring Suncor into compliance with the Commerce City refinery’s air permits.

“Blocking this permit is a step in the right direction, but more needs to be done to hold Suncor accountable for the untold amount of toxins it is spewing into our air,” DeGette said.

Suncor has a long history of polluting the air and water in Colorado.

In 2020, the company agreed to a $9 million settlement with the state for multiple air pollution violations between 2017 and 2020.

And the state is investigating multiple air and water violations that have happened since 2020, with the most recent being a notice over benzene releases this year into Sand Creek.

Suncor’s air permit for Plant 2, which sets the amount of various pollutants the refinery is allowed to release into the air, is long overdue.

The permit was issued in 2006 and last revised in 2009. The permits are supposed to be renewed every five years, but the state health department, which first must write the permit before sending it to the EPA for approval, was behind in its permitting process.

The EPA already objected once to the Plant 2 permit after it was submitted on Feb. 9, 2022. The agency sent the permit back to the health department, saying it was not in compliance with the Clean Air Act and ordered Colorado regulators to try again.

In that objection, the EPA wanted the state to monitor three sites where Suncor uses flares to burn off excess chemicals. Originally, the Air Pollution Control Division wanted to exempt those flares from regular monitoring, but the EPA wanted more analysis to justify those exemptions.

The state then developed specific monitoring plans for flaring sites at Plant 2, a truck loading dock and a railcar loading site, and the EPA accepted the changes.

But environmental groups still argued the latest version of the permit did not meet Clean Air Act requirements and asked the EPA to reconsider. And in its 99-page response released Tuesday, the EPA agreed.

It’s unclear how the state’s response will unfold. If the Air Pollution Control Division’s revisions are significant enough, it could force the state to reopen public comment and hold more hearings on the permit. Once the revisions are made, the EPA would have 45 days to approve the permit.

The Commerce City site has two air permits, and the one that regulates Plants 1 and 3 remains under review by the EPA. The refinery also has an overdue water-quality permit that is under consideration by the state, and environmentalists are pushing for tougher restrictions on PFAS discharges into Sand Creek.

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