The leak at the Suncor plant in Commerce City does not pose a risk to public health, according to the Colorado Department of Health and Environment.
The water stream leak was first reported around 9 a.m. at the plant on Brighton Boulevard near 56th Avenue.
The leak occurred in a bore underneath Brighton Boulevard between two of the plants - Plant 1 and Plant 3, according to Mark Salley with the health department.
Crews closed Brighton Boulevard as a precaution as they investigated.
The leaking pipe was a 2" water pipe carrying waste water to the Waste Water Treatment Plant (WWTP) at Plant 3, Salley said.
"Since the water could contain trace amounts of hydrogen sulfide (H2S), they monitored the air close to the water on either side of Brighton Blvd, as well as in the surrounding area," Salley said.
Salley said only "very small amounts of [hydrogen sulfide] were detected and only detected very close to the waste water itself."
Salley said the leaking pipe was quickly isolated and Suncor used a vacuum truck to clean up the waste water. That water was sent to the WWTP (where it was headed originally), Salley said.
"We immediately initiated our response plan and the leak has been isolated and a team is working to resolve the situation," Suncor officials said in a news release sent to Denver7. "There were no injuries reported and everyone is accounted for."
"The appropriate regulatory agencies have been notified and we are working closely with them," officials said. "A full investigation will be initiated as soon as response activities allow."
The Commerce City plant refines 98,000 barrels per day producing gasoline, diesel fuel and paving-grade asphalt, according to Suncor's website.