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The Suncor Energy oil refinery on July 18, 2021, in Commerce City. (Photo By Kathryn Scott)

The Suncor refinery’s voluntary air pollution monitoring site is now live on the internet, and the Commerce City petroleum refiner will add mobile van monitoring reports next week. 

The refinery, which has battled neighborhood activists and environmental groups for years over toxic air and water emissions that periodically hit Adams County and north Denver, said the new stationary and mobile monitoring is part of its commitment to reporting potential toxins and improving community relations. 

Suncor planned the monitoring program after agreeing in 2020 to a $9 million settlement with state health officials over pollution violations from 2017 through 2019. Suncor says the new monitors were not part of that settlement, but were in response to talks with the community in 2020. 

Some of those activists, though, said they still don’t trust Suncor to be transparent, and are far more interested in the monitoring and reporting required by legislation passed in the spring. That law requires extensive air monitoring along the fence lines of a number of polluting industries, including the refinery. 

The voluntary monitoring is a “step in the right direction” in offering general, current air quality information, said state Sen. Dominick Moreno, a Commerce City Democrat. But it lacks data comparing what Suncor is emitting to what its state pollution permits allow, he added. 

Commerce City Suncor air monitoring north Denver web site
Suncor has activated a new air pollution monitoring system around its fence line in Commerce City, giving real-time information about a handful of the most toxic air pollutants. The refinery will also add in mobile monitoring data in coming weeks. The web site can be found at (Screenshot of, Aug. 25, 2021)

“That is life-critical information for communities that surround that facility, and so I do think there are some improvements that could be made to the tool and I will be submitting that feedback directly,” Moreno said at a community clean air conference this week. 

Suncor’s voluntary monitoring site can be found at, for Commerce City North Denver Air Monitoring. The upper right corner of the web page shows real-time overall air quality monitoring numbers from state equipment, providing the Air Quality Index for a handful of communities. 

The map dominating the main web page gives numbered, clickable points representing the fixed monitors around Suncor’s large footprint in Commerce City. Those sites, operated by Montrose Air Quality Services, provide 60-minute averages of measured pollutants including carbon monoxide, sulfur dioxide, nitrogen oxides, PM 2.5 particulate matter, hydrogen sulfide and volatile organic compounds. The information is available in Spanish and English. 

The monitors are not only measuring Suncor-related air, of course. They pick up pollutants from all the industries in the area, power plants, auto emissions, and in the case of PM 2.5, the smoke from wildfires as far away as Canada. Elevated hydrogen sulfide readings could come from Suncor’s flaring towers, or from nearby wastewater treatment or power plants, for example. 

If there is an emission incident at Suncor, residents or researchers would be able to click on the monitoring sites and see months of recent patterns in addition to present data. 

The monitors update every five minutes, a Montrose Air technician said, and the PM 2.5 monitors at Suncor showed the first inflows of West Coast wildfires this summer before the state’s monitors were updated. 

Mobile monitoring will happen every three months, and those results will also be added on the web site. 

The separate state-mandated monitoring will eventually begin under House Bill 1189, which requires fenceline monitoring of pollutants from specific industries, including refineries, petroleum distribution sites and aerospace materials manufacturers. That bill requires monitoring of benzene and hydrogen cyanide, in addition to hydrogen sulfide.

The communities around Suncor often note that they have gained a reputation as one of the most polluted ZIP codes in the nation because of the refinery, other industries, auto emissions from highways, and a long history of smelting metals in north Denver. 

They have recently sought and passed tougher reporting legislation, citing health studies that prove high rates of asthma, lung disease, heart disease and other pollution-related illnesses in the area. They have also sought economic and environmental justice provisions in legislation and regulations, noting the  communities are often populated with Hispanic, indigenous and other people of color with lower incomes that complicate health care or the ability to move away.

Michael Booth is the Sun’s environment writer, and co-author of the Sun’s weekly climate and health newsletter The Temperature. He is co-author with Jennifer Brown of the Colorado Book Award-winning food safety investigation “Eating Dangerously.” Booth was part of teams that won two Pulitzer Prizes for breaking news. He also writes frequently about inexplicable obsessions that include tamarisk, black-footed ferrets and tire fires. Booth also serves as the underpaid driver for four children, and plans to eventually hike every inch of Colorado.