The Fort Frances paper mill is almost fully demolished, with only the Biomass building standing. But what is going to happen with the lagoon?
The lagoon is the underground facility that was used for the treatment of the wastewater from the Kraft and paper mills.
It was originally built in 1970 to just handle the wastewater from the Kraft Mill.
Gary Rogozinski, the mill’s environmental manager and superintendent for 33 years, said the mill decided in the later 1970s to treat all the wastewater because there was no wastewater treated from the paper mill. It just went right into the river.
“The treatment system was too small and it was expanded two or three times over the course of 30 years,” Rogozinski said. “It was modified and increased in size so that it went from two cells to three cells with the second cell being a really, really big cell. The paper mill wastewater was added probably in the late 70s, and they joined underground.”
Rogozinski said the water line ran from the mill to the treatment system on eighth street. The water stayed in the system for treatment before going back to the river by gravity.
The clay-lined lagoon has two settling basins with no aeration, which looks after the water filtration process. Rogozinski said solids would settle down in this stage.
The water then moved from the settling basins to the aerated basins.
“It uses large mixers. The whole treatment system is filled with microorganisms so they made air, nitrogen and phosphorus in order for them to eat the contaminants in the waste water,” Rogozinski said. “It would go from the settling basins into the aerated basins, they would add a nitrogen and phosphorus source. It would stay in there, microorganisms would digest the or eat the organic material. And then it would flow back into the river.”
Rogozinski said there was frequent testing done into the settling basins, out of the settling basins and all through the aerated system to make sure it was effective. The water was also tested before it went to the river.
“There were [also] groundwater wells in various locations around that were tested monthly in the summertime of course to make sure there was no leakage from the basins,” Rogozinski added.
With the mill almost fully demolished, Rogozinski said he does not know what is going to happen to the lagoon.
Rogozinski said since there is nothing going back to the river, the option to close it could be done in two different ways.
The first option is completely draining them, knocking the walls over to fill it in and levelling it out.
“Because one is 20 feet deep and the other ones are about 12 feet deep you’d have to drain them, clean them, and then knock the clay walls,” Rogozinski added.
Another option, though not economically feasible, would be to fill it in, Rogozinski said.
“But that’s a lot of fill. The new basin is 20 ft. deep and it’s huge. Those things held millions and millions of gallons of water. The option of filling them in is not economically feasible. The best option would be to clean it out and knock down the walls for safety reasons.”
The lagoon could also be drained and left, but Rogozinski said there is also a safety concern with leaving it.
“Kids are kids if somebody walks in there they can potentially hurt themselves,” Rogozinski said. “It will fill with water. “It’s fairly steep, and it’s clay so if you fell, it’d be slippery. It would be very difficult to walk up.”
Finally, Rogozinski said it could potentially be reused, because the fibreglass underground pipes are about 36 inches in diameter.
However, Rogozinski said integrity of it might be a concern. Because even though they are strong pipes, there were breaks in them over the years due to contractions from the cold weather.