The Suncor Energy oil refinery in Commerce City spewed harmful pollutants into the atmosphere Wednesday night after extreme cold triggered a shutdown across the plant’s operations.
The excess emissions included hydrogen sulfide, sulfur dioxide, opacity and visible emissions, said Leah Schleifer, a Colorado Department of Public Health and Environment spokeswoman.
The excess emissions listed by CDPHE were:
- Hydrogen sulfide exceedance from flares at Plant 1 Main Plant Flare, Plant 2 Main Plant Flare and Plant 3 Flare
- Sulfur dioxide exceedances from the Plant 1 Sulfur Plant Incinerator
- Visible emissions limit exceedances from the Plant 1 Main Plant Flare
- Opacity exceedance from the Plant 1 Fluidized Catalytic Cracking Unit
State officials are assessing the potential public health risks as Suncor provides more information, Schleifer said.
The state’s Air Pollution Control Division, which falls under CDPHE, is reviewing air monitoring data provided by Suncor and Cultivando, a community nonprofit that serves as a watchdog over the plant’s emissions. So far, inspectors believe hydrogen sulfide and sulfur dioxide levels are below the levels that cause adverse health effects, she said.
“We will continue to assess available data and information over the coming days to better understand any potential risk associated with the upset,” Schleifer wrote in an email to Pointypress.
Loa Esquilin Garcia, a Suncor spokeswoman, declined to comment Thursday when asked about the shutdown.
The shutdown started at 8 p.m. Wednesday when cold weather caused Suncor’s hydrogen plant to trip, creating a cascading effect throughout the refinery, Schleifer said. At 3 a.m. Thursday, Suncor sent emergency notifications via text, phone call and email to community members who are registered to receive such alerts.
The shutdown was ongoing as of 1 p.m. Friday, Schleifer said. Some units remain offline and others are operating at a minimal rate.
“Suncor is required to provide additional reporting to CDPHE as long as this incident is ongoing and we will continue to review and assess those data to inform our response and provide necessary updates to the public. Based on current data, we do not anticipate significant updates over the weekend,” Schleifer said. “As we continue to investigate this issue, we intend to take any necessary enforcement actions as determined by our experts and available data.”
Suncor is the only oil and gas refinery in Colorado and processes about 98,000 barrels of oil a day. It also manufactures most of the asphalt used to pave Colorado’s roads.
But the refinery is the largest single source of air pollution in the state and is under intense scrutiny because of multiple air pollution violations. In 2020, the company agreed to a $9 million settlement with the state for its violations, and that settlement included more community air monitoring.
Last summer, Suncor installed new automated shutdown systems inside two gasoline-producing plants at its Commerce City refinery to prevent a repeat of a 2019 malfunction that blasted a clay-like substance into the surrounding neighborhood.