Abandoned mines: Dangerous for humans, beneficial for bats


Staff Writer

NORWAY – Dickinson County is rich in mining history. Remnants of old mines, such as open pits, shafts, and sinkholes are scattered throughout the area.

It’s the job of Dickinson County Mine Inspector Steven Smith to make sure those places are as safe as possible.

Smith recently gave a presentation on his mine experiences to a packed house at the Jake Menghini Museum in Norway.

As he explained, he actually wears two hats when it comes to abandoned mines.

As the county mine inspector, he visits every mine site in the county to make sure there are no unsafe conditions. If he finds fencing deficiencies, he follows up with the property owners in an attempt to get the situation remedied.

As a contract worker for Eastern Michigan University, Smith locates and monitors bat populations in old mines throughout the Upper Peninsula. He helps biologists find mine locations, provides transportation to the sites, and figures out how to safely enter the mines.

Smith said that in Dickinson County alone, there are hundreds of mine “features.”

“A mine actually covers a huge area,” he noted. “Some features are shafts, some are cave-ins, some are test pits.”

Of these hundreds of features, Smith estimates that dozens are still unsafe. They may lack proper fencing, or there may be new subsidence, in which the ground surface shifts down.

One area that is particularly dangerous is the Pewabic Mine site in Iron Mountain. There have been two fatalities at that location in the past 25 years.

Smith added that new features, in the form of sinkholes, periodically open up. Often, these holes can simply be filled in. But, as Smith pointed out, it can take several attempts to completely fill a sinkhole.

“It’s all a work in progress,” he said. “They can come back again and again while the material settles.”

Depending on the rate of this year’s spring thaw, more sinkholes could open up in the next couple of months.

“Springtime is the time of year there’s more danger of sinkholes,” said Smith. “The ground is soft and the frost is moving, but it really depends on the thaw.”

Smith recommends that citizens obey all warning signs and not damage fencing around any type of mine feature, no matter how small.

“There are real dangers,” he said.

Though abandoned mine sites can be hazardous areas for humans, they provide a haven for hibernating bats.

Smith first got interested in bats in the early 1990s when the old Mille Hill Mine in Iron Mountain was going to be filled in. The mine, which was home to a large bat population, was eventually gated instead of filled in.

Gating old mines prevents humans from falling in, but allows bats to move in and out. In the case of the Millie Hill Mine, the gated area also acts as a tourist attraction where people can go to view bats.

Along with Dr. Allen Kurta of Eastern Michigan University, Smith spends his winters traveling across the Upper Peninsula from mine to mine in order to monitor hibernating bats. One of their goals is to check for the spread of a disease called white nose syndrome.

White nose syndrome is a fungal disease that irritates bats while they hibernate. The bats wake up more often, use up their stored body fat, and die.

Since the initial outbreak in 2006 in New York, millions of bats in the United States have succumbed to the disease. It has spread by humans who go into caves and old mines, and by bats themselves.

So far, Smith and Dr. Kurta have found no sign of white nose syndrome anywhere in Michigan. That’s a good thing, Smith said, since bats help humans by keeping the insect population down and by pollinating plants.

If white nose syndrome ever does make its way to Michigan, not much can be done to stop it.

Nikki Younk’s e-mail address is