DENVER (CBS4) – Suncor Energy says the spill of oily material flowing into Sand Creek has been contained.

Crews for the company have been working since Monday to secure the problem and clean up the mess.

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Suncor operates a refinery in Commerce City. Teams are still trying to pinpoint the exact source, but they’re checking out a report by Suncor of a damaged pipe that runs between the refinery and a storage tank.

A fisherman told CBS4 he reported the leak more than a day before authorities were able to find it. The fisherman’s story raises questions about the state’s spill hotline.

“I could just smell it,” Trevor Tanner said.

Trevor Tanner (credit: CBS)

Tanner was fishing where Sand Creek joins the South Platte River when he noticed an oily sheen on the water.

“It was clearly coming out of Sand Creek,” Tanner said.

It happened on Sunday morning. Using his cellphone, he called the state health department, persisting through several menu options to finally reach the spill hotline manned by a duty officer.

“His first question was, ‘Can I call you back in 20 minutes?’ And I got offended at that point,” Tanner said.

The duty officer apologized and took his information. Tanner left to fish elsewhere, but throughout the day, health officials called Tanner back to say they were looking but couldn’t verify the spill.

“I came up with the number that said hotline. I thought, ‘Here it is. This is who I need to call and they’re going to come in sirens blazing.’ That’s not the response that I got.”

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Tanner made the right call, according to the spokesman for the Colorado Department of Public Health and Environment, Mark Salley. He said his agency acted appropriately.

“To make it look like we were sitting on our hands is not accurate in any way,” Salley said.

Salley said Tanner’s information was forwarded to the Tri-County Health Department. Someone from that agency did check the river, according to Salley, but found nothing.

It took another day for the Environmental Protection Agency to confirm the oil spill on Sand Creek.

But Tanner believes the EPA response on Monday was at least partially due to his posting the detailed story Sunday in this online blog.

“Maybe people feel that’s a rapid response. I feel that’s a failure,” Tanner said.

The EPA is still processing samples of the water to figure out what the substance is while Suncor crews work to keep it from reaching the South Platte and eventually stopping the leak altogether.

“We are sampling this material. We did a series of samples throughout the day,” EPA coordinator Curtis Kimbel said.

The work will continue through Wednesday night into Thursday and crews are already anticipating the colder weather and freezing temperatures expected overnight.

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“We’ll work through the night regardless of whether it snows or not,” Kimbel said. “They’ll be here for the duration.”