"They've got to be here for as long as it takes to monitor what's going on along that river, for sure," guide Garry Pierce of Tailwater Drifters said Monday.
"I just hope they're not going to come in for three weeks or a month and say 'Oh yeah, we're good. We've got it cleaned up, and off we go.' That's just not going to be good enough."
Kelsey Kure, who lives on about two kilometres of waterfront along the affected part of the river, agreed.
"There has to be a study done to determine the effects of this. You can't just go on pretending that nothing happened, that there are no impacts."
On Thursday night, a section of pipeline owned by Plains Midstream Canada running under the river near Sundre leaked up to 475,000 litres of oil.
The company has said high river levels flushed most of the oil downstream into Gleniffer Lake, a man-made reservoir and popular recreational area.
On Monday, Plains Midstream said the oil release had been stopped within booms placed on the lake. A skimmer was removing oil from the lake and absorbent pads were soaking up oil at the site of the leak. Wildlife deterrents have been placed to try and keep animals from the water.
Crews were working to clean shorelines and remove contaminated debris. More than 170 people were working on cleanup and remediation, the company said in a release.
But that doesn't mean there won't be consequences. Kure, a water resource technician for a forestry company, said oil is pooling up along the river's margins.
"(Oil) got mixed in with all the silt and sediment in the river. So wherever there's sediment, there's oil particles."
He also points out the affected stretch of river is highly braided.
"You're not talking about one channel. You're talking six to seven to 10 channels. That just increases your impact area."
As well, oil is fouling a number of protected spots along the river, such as the Butcher Creek Natural Area, home to 58 bird species.
Both Kure and Pierce fear the spill will kill off many insects in the water that are just now emerging from their eggs. It could also contaminate river bottom gravel, a spawning habitat for trout.
They said that's going to damage a fishery that people come from around the world to enjoy.
"I got an email from one of my clients two days ago, from Denmark, who's already heard about the oil spill and wants to know the impact it's going to take on the rivers I guide him on," Pierce said. "I told him what I could tell him — we got our fingers crossed that things are going to get cleaned up fast."
Phil French, head of the Red Deer River Naturalists, was at the spill site over the weekend. He said although water levels have begun to recede, it won't be possible to estimate the damage until river flow is back to normal.
"There was oil everywhere there," he said.
"It's going to affect the ecology of that part of the Red Deer River valley for a long, long time. I'm pretty sure I'll be in my grave and they'll be still feeling the effects of this oil spill."
French said his group is already preparing a request to the Alberta government for long-term monitoring of the spill's after-effects.
"We are calling for that — long-term environmental monitoring of that part of the river," he said. "We really don't know what the long-term effects are going to be."
A spokesman for Alberta Environment was not immediately available for comment.
— By Bob Weber in Edmonton
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