Cold temperatures cause extra large vapor clouds over Suncor refinery, Xcel plant

Thick clouds of steam billowed over Commerce City on Wednesday morning and combined with a bad smell to cause concern among residents who live near the Suncor Energy oil refinery.

However, representatives from Suncor and the state’s Air Pollution Control Division said there were no excessive emissions reported. Instead, they said the large vapor clouds were the result of cold temperatures, and the odor came from what Suncor described as “sour water transfer,” which is a process for treating water that has been used in oil refining operations.

The Air Pollution Control Division dispatched an inspector to Suncor after receiving reports about the large vapor clouds and strong odor, said Kate Malloy, a division spokeswoman.

“We have not found any malfunctions or incidents that would have caused black smoke. Instead, we understand that there may have been more prominent steam clouds coming from the refinery because of the colder temperatures this morning, so that may be what residents noticed,” Malloy said in an email to The Denver Post.

Amy Fidelis, a Suncor spokeswoman, also said in an email to The Post that cold temperatures, which were in the teens early Wednesday morning, could have made the steam appear darker.

Xcel Energy’s Cherokee Generating Station, which is also in the area, was emitting large steam clouds, too. But Kevin Coss, an Xcel spokesman, said colder weather causes the vapor to be more visible. That steam does not cause an odor.