October 08, 2018 05:53 AM
The Minnesota Pollution Control Agency and the Minnesota Department of Natural Resources are investigating a sediment spill into the St. Croix River after recent heavy rain caused retention ponds to flood at an old gravel mine in Washington County near Scandia.
Carnelian-Marine-St. Croix Watershed District Director Jim Shaver told 5 EYEWITNESS NEWS he estimates about "100 tons of sediment" spilled down a bluff into what's known as Middle Creek and then into the St. Croix River in the past couple weeks after a lot of rain in the area.
"The retention ponds here at the old gravel mine, which is now a solar farm, just did not hold the water," Shaver said. "So, the MPCA and the DNR, along with probably the Wildlife Service at some point, will all be out here surveying what happened and working on remediation."
The sediment is considered a pollutant even though it is naturally occurring because, Shaver said, it is something that does not belong in the creek or the river and can damage living organisms.
"Nature is pretty resilient and the creek and river should be fine over time," Shaver said. "But, with that said, it can cause problems for the biota in the creek and river and is not something you really want to see repeated anywhere along the creek or river."
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Kristin Tuenge lives along Middle Creek and told 5 EYEWITNESS NEWS she opposed the gravel mine when it went in years ago and has always had concerns about the retention and overflow ponds being able to handle heavy rains.
"We were told the retention ponds could handle two straight days of six inches, or more, of rain," Tuenge said. "Well, we now know that is not true and damage goes beyond the creek and river as you see huge trees all over the bluff uprooted and just gone."
Tuenge said the area where the flooding and sediment spill happened is a fragile ecosystem and protecting the St. Croix River and its tributaries should be of the highest concern.
"This is such a beautiful area and the St. Croix River is a national treasure," Tuenge said. "Something like this should never happen and we have to make sure it never happens again."
An Arizona company by the name of BHE Renewables owns the site where the solar farm now stands and told 5 EYEWITNESS NEWS it is working to fix the problem but did not want to comment further until the state completes its investigation.
Updated: October 08, 2018 05:53 AM
Created: October 07, 2018 08:35 PM
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