Ironwood: Paradise Lost or Regained?

Fetch it Baron! The surface iron mining pits that Hanna Mining Company closed in the l960's have an interesting history. Many contained springs and filled with water becoming farm ponds and in several instances nature preserves. One, the state managed Goethite Wildlife Management area, is a prime duck hunting and birding area. Baron loves to play fetch there as we walk the area on my birding outings. In at least one pit nearby things did not develop so favorably. The large ore pit was turned into a "sanitary landfill." This is the story of Ironwood.

The region now called "Bluff County (i.e. southeastern Minnesota) contains what is called "karst topography." This means an area full of springs, caves, sinkholes, blind alleys, and disappearing rivers, where slightly acidic waters disolved fractured bedrocks. What is all adds up to is that the complicated connections between surface water and ground water leave the area highly vulnerable to contaminaton. So a large landfill was created in the early 70's - bad enough - and then it got worse.

Surface water going into a sink hole isn't filtered and goes directly into the ground water. In a landfill if the upper bedrock has been penetrated in the mining operations water again goes directly into the ground water strata.

Ironwood landfill was closed in 1980 after irate local citizens brought it to statewide and national attention. Illegal dumping of toxic wastes by a Wisconsin transfer company was occuring and finally discovered. Eventually it became Minnesotas first superfund site. A dubious distinction at best. Over1400 barrels of manfacturing solvents were initialy excavated in 1981. Hundreds of monitoring wells and pump out were installed. Approaching thirty years later, close to 2 million dollars have been spent on the clean up and containment. Hundreds of millions of gallons of water have been pumped out to try and contain the contamination plume. It is sent to a lagoon in the hope that the volatile compounds will disapate safely. Then it is pumped, after reaching an acceptable standard into the South Branch of the Root River (a prime trout stream).

Today most of the water released from the lagoon is below the Health Risk Limits (HRL). However,

the vinyl chloride concentrations remain well above the HRL. Vinyl chloride is a highly toxic breakdown product of the compounds in the illegal barrels and in other landfill materials deposited at the site.

Today the landfill appears as a rather bucolic hayfield with some strange pipes sticking out of the ground all over.
Hundreds of test wells are scattered throughout the countryside.

A twenty to thirty foot berm surrounds the huge evaporation lagoon. Baron and I hike through the whole area . Wild turkeys scatter, an occasional doe with fawns flees into the heavy cover, we see bobolinks and meadow larks, a dozen cedar wax wings in the top of some dead timber. Warblers hide in the red and white pines which surround the base of the berm. We follow the gravel road which connects all the monitoring stations. It a fun place to go for a walk. Baron approaches the lagoon. Wants to go in wading. "No", I yell. "Bad water, Baron. Come." He comes back looking a little displeased. Good walk though. Some bad memories though. Time to go home.

The data for this post was taken from the DNR. Minnesota's fine and often unfairly maligned Conservation agency.