(KPAX) The agencies overseeing the cleanup of the old Smurfit Stone Container Corp. mill site say the owners are being required to have plans in place to repair berms along the Clark Fork River, reducing the risk of contamination being released downstream.

The order for the plans is coming in direct response to record floods along the river that drew attention to berms' potential of being overtopped by flood waters.

During last spring’s record floods on the Clark Fork, there were several days when the high water came within a few feet of going over the berms.

The structures were installed decades ago during the pulp and paper mill’s operations to separate the river from the “cooling ponds” that make up the mill’s western edge.

But concerns by Missoula County and the Clark Fork Coalition grew after the release of some “tea colored” water, which led to an order for the property owners to make repairs.

At a briefing last week, the Environmental Protection Agency and Montana Department of Environmental Quality explained a berm study showed the structures are sound.

But if waters got higher than last spring there could be real problems. And that’s where the agencies are working with the potentially responsible parties — the owners — to make the berms more secure.

“The new geo-tech studies of the berms show the berm won’t overtop at a hundred-year high flow event. But it could overtop at something greater than that, say a 150 or 200-hundred year, it could definitely go over the top of the outside berm,” said Keith Large with the DEQ.

“The inside berm hasn’t had a study done on it. Though EPA and DEQ recommended last year that the P-R-Ps do that. And they said ‘no we just want to do the outside one now.’ “

The problem is, no one is really confident about the integrity of the berms since they’ve been largely ignored for nearly a decade since Smurfit shutdown.

“They’re legitimate concerns. Because these are earthen berms that weren’t really engineered like we engineer stuff today. They just kind of built them out of native material, Large said.

“So sooner or later they have the potential to erode away. The company has not been doing a lot of maintenance on them since 2010, so we need them to start putting together plan so that we have that contingency plan.”

Those contingency plans start with a scheme for making emergency repairs. That’s in the process of being approved right now, with EPA and DEQ taking public comments.

“They’ll give them a call. They have six hours to respond. And they know where there’s clean material. They can go out there if they start to see a failure they can start patching it up so that it doesn’t completely fail,” Large said.

The repair plans likely won’t be in approved and in place for this flood season. But the agencies are hoping to have them effective for coming years, while the final remediation plans are developed for the entire Smurfit site.