Suncor’s refinery spilled too much cyanide into Sand Creek in February

The Suncor Energy refinery in Commerce City spilled too much cyanide into Sand Creek last month, according to a notification from the company.

The excessive amount of cyanide was discovered during routine testing on Feb. 25, the company reported on Wednesday evening. The test found cyanide levels above 20 parts per billion, above the permitted level of 17 parts per billion.

A water sample tested two days later found the refinery was back in compliance with its water pollution permit. The notification was sent via phone calls, text messages and emails to those who have enrolled in the refinery’s alert system.

The spill is under investigation by the Colorado Department of Public Health and Environment.

The cyanide was released into Sand Creek via Outfall 20, a pipe that is the main wastewater discharge point for the refinery. That pipe pours 3.5 million gallons of water per day into Sand Creek, a tributary to the Platte River — a source of drinking water for residents and irrigation for farmers in northern Colorado and Nebraska.