Searching for history in St. Louis River mud

By KBJR News 1

July 2, 2014 Updated Jul 2, 2014 at 9:42 PM CST

Duluth, MN (NNCNOW.com) --- The St. Louis River has an industrial history that's still haunting the waterway.

Now research is being done to figure out what was normal on the river before extreme pollution occurred.

"This river before the... especially back in the 60's and 70's looked terrible, there was oil, there was scum, people saw foam on the river" said Diane Desotelle of the Minnesota Pollution Control Agency.

It's a situation that the St. Louis River has been recovering from across generations. Looking at the water today, it's not as easy to see the destruction that was caused, but if you look under the water...

Senior Research Assistant at NRRI, Euan Reavie and his team have been pulling history from the bottom of the St. Louis River in the form of sediments.

"A big focus of the work that we do is actually using algae. Algae species in particular which can tell us about environmental condition"
said Senior Research Assistant at NRRI, Euan Reavie.

Algae species under the name of diatoms have left fossils that settle into the sediment.

"We find hundreds and hundreds of diatoms for each of these slides and each of them means something a little bit different for the core and will hopefully tell us something about the water quality" said Research Assistant, Elizabeth Alexson.

"These diatoms leave tracers of the conditions as they evolved over time and what we did" said Research Fellow, Lisa Allinger.

What we did was industrialize much of the area around the waterway.
The sediment will show researchers up to 300 years of data going back well before European settlers came to the Northland.
The river has been on the rebound since water treatment facilities and other environmental practices have been put in place, but researchers hope the sediment will reveal the baseline to which they hope the river will rebound.

"We don't have that nail in the coffin that tells us that indeed we have rehabilitated this ecosystem. It is much better than it than it used to be and we have dealt with these beneficial use impairments" said Reavie.

The river is currently listed as an area of concern by the Minnesota Pollution Control Agency. The data found will help shape policy around the river and ultimately answer the big question...

"Have we shown significant enough rehabilitation of the ecosystem that we can delist it as an area of concern?" said Reavie.

That answer will come in the future after scientists fully understand the past.

Researchers expect their analysis of data will be complete in about a year and a half. From there, the MPCA and EPA will use the data to make policy decisions about the river.

Bryce Henry
bhenry@kbjr.com