Local and state officials continue to monitor the Rainy River below International Falls after a sulfuric acid spill at the city’s Boise Paper mill last week.
Meanwhile, officials in Canadian communities along the river have expressed concern about a delay in receiving notification of the incident affecting the river that forms the border between Minnesota and Ontario.
Kiley Shebagegit, the watershed coordinator for Rainy River First Nations, told CBC Thunder Bay that the community was not notified of the spill until five days after it occurred. The spill happened on July 20 and was quickly reported to the Minnesota Pollution Control Agency. News of the spill did not reach local media until this week.
“RRFN’s concerns are twofold: firstly that the spill occurred … and secondly that it was not reported,” Shebagegit told CBC in an email.
The company that owns the mill said earlier this week that the acid spilled into the mill sewer and then entered the mill’s wastewater treatment plant, where it “impaired the wastewater treatment plant biology.” The mill was shut down until the treatment plant was restored; the mill was back in operation this week.
The Minnesota Pollution Control Agency reported that it was notified that about 2,000 to 3,000 gallons of sulfuric acid spilled at the plant.
The company took immediate steps to neutralize the acid and did manage to mitigate at least some of the spill, the MPCA’s Jeff Stollenwerk told the News Tribune on Friday. But the company reported a drop in pH in the mill discharge and in the river, which Stollenwerk said is a “strong indicator” that at least some of the acid reached the river — though he said it appears that whatever reached the river was substantially diluted.
In the wake of the spill, county and state officials have patrolled the river below the mill, looking in particular for signs of a fish kill and collecting water samples.
“At this point we haven’t documented any obvious impacts to the river,” said Stollenwerk, who is the MPCA’s industrial water section manager based in Duluth — but the monitoring is ongoing.
He said the cause of the spill remains under investigation.
Stollenwerk said there is a protocol for communicating such incidents to potentially affected communities and groups, and that’s still under review in this case.
“We’ve looked directly at Minnesota’s role in following that protocol, and we believe we did follow it,” he said. “… We have a certain role, and we looked at how our responders fulfilled that role, and it looks like they completed each of their steps. So now we’re looking further down the line (at) what was everyone else supposed to do, and where did things stop?”
He said the concerns raised by downstream communities are “legitimate and serious … and we are following up on this entire protocol to see where things fell…