As longwall mining at Deer Run Mine in Hillsboro passed under Route 185 this spring, highway travelers had a front-row seat to the subsidence left behind.
E&G Construction of Coffeen is not only the company that is tasked with mitigation of the subsidence of the road as mining occurs in real time, but also with repairing mining impacts on the land.
“I go back to the day I met Gerry Spinner, and he was a doubting Thomas,” coal company official Roger Dennison said of the public debate over a 2006 referendum that, if passed, would have prohibited longwall mining in Montgomery County. “Now I owe it all to him for coming up with the underground drainage system.”
With Route 185, though, E&G’s job has been to keep the highway passable–under Illinois Department of Transportation (IDOT) direction–until the state determines what final repairs need to be made.
“Now it’s like driving over 2,600 feet of railroad tracks,” Spinner said of the condition of the subsided part of Route 185.
Deer Run had been mining two shifts a day, from 7 a.m. to 11 p.m., until a rock collapse caused elevated carbon monoxide levels and a temporary shut-down. The mine finished passing under the highway just before that.
“About 10 days after the mine passes through, we’re seeing about 95 percent of the droppage,” Spinner said.
IDOT has set the rules for mitigation while the mine passes under the highway–including things like warning signs and speed limits–and is on the site four times a week. After the mine passes under the highway, IDOT will write the specs for fixing the road, the job will be put out for bids, and “the coal mine will be writing the check,” Spinner said.
In the years to come, as mining moves south while extracting coal from east-west panels, the longwall will pass under Route 185 two more full panels and two partial panels, all southeast of the present subsidence.
Although E&G work on land reclamation after subsidence has drawn attention from around the country and around the world, many land owners in the path of the mine are still apprehensive about planned subsidence and the reclamation process.
“IDNR (the Illinois Department of Natural Resources) has brought in people from other countries and other areas of this country who want to know what we’re doing that’s working.”
The “what we’re doing” is the underground drainage system idea that Spinner first suggested to the mine company during his “doubting Thomas” days. The principle is to repair subsidence-caused drainage problems not on a land-owner by land-owner case, but area-wide like in a drainage district.
“You’re dropping the most prime ground in the world,” Spinner said, looking at a detailed drainage map of the mining area. “How are you doing that? Some of this stuff doesn’t drain well now. If you drop it six and a half feet, that’s not going to improve it.”
Absent an area-wide approach, after subsidence a mine company would simply write out checks to land owners and leave them the responsibility of repairing drainage issues however they choose.
The problem with that, Spinner said, is “you can only drain ground as good as your neighbor will let you. If the option was to cut a ditch, and the lower farmer says, ‘hell no,’ then that doesn’t work.”
Spinner believes using underground tile systems to get water to streams not only improves drainage, but also water quality. He has consulted with the federal Natural Resources Conservation Service (NRCS), and listens to producers.
“I want to know where the worst part of his field is today, because that’s going to be the worst after subsidence.”
Federal law also has a say in the ultimate result of drainage. Water that is headed for a certain stream still has to end up there.
Spinner believes underground systems not only improve drainage without production-eating ditches, but by using upgrades such as in-line water level control boxes, a producer can better manage moisture and better manage nutrient run-off.
“I think I can improve drainage from before,” Spinner said. “If you can make something better without making it more costly, why not?”
Both E&G and the mine have financial incentives to produce results when it comes to subsidence repairs. The mine has to track farm yields over subsided ground and pay the difference if production is diminished–year after year, “so they want me to make sure it’s getting good yields,” Spinner said. “We look for ways to increase the yields.”
His financial incentive? “I’m hired one job at a time,” the contractor said. “They give me a purchase order, and if I don’t do a good job, I’m not hired for the next one.”
So far, so good. But Spinner still has to prove himself not only to the mine on each new job, but also to each land owner impacted by subsidence.
A crew of 12 works for Spinner at E&G, 11 of whom live in the Hillsboro School District.
“I’m lucky to have a bunch of local people who are making this work,” Spinner said.
Coal mined in Hillsboro is going to ADM in Decatur, Duke Energy in Indiana, to Baltimore, and outside of the country.