FGD project at Conesville Coal prep plant

Conesville Coal Preparation Company, Conesville Generating Station and the Ohio Department of Natural Resources (ODNR) are working together to reclaim a 1950s-vintage surface mine that was abandoned, leaving behind acid mine drainage and a dangerous 100-foot highwall.

The abandoned mine is located on Conesville Coal Preparation Company´s property. Runoff from approximately 30 acres mixes with seepage emerging from the coal seam, resulting in water with a pH of about 3.0. CuFGDrrently, the prep plant must treat this acidic water to neutralize its caustic effects before it leaves the property. The pit generates approximately 100 gallons per minute of acid mine drainage water.

"This is a long-term problem for us," said Royal Wilson, technical services and administrative manager for Conesville Coal Preparation Company, which washes the coal Conesville Power Plant burns in its units 1, 2, 3 and 4.

"It´s a liability here now and a liability for AEP for years to come. While there are extra costs associated with doing this reclamation now, in the long run, we will save millions of dollars in costs for perpetual treatment of this runoff. Ultimately, this also will improve the water quality of (nearby) Wills Creek."

Ted Morrow and Jody Belviso of AEP´s Environmental Services Department worked with the ODNR Abandoned Mine Land (AML) program manager and staff to successfully negotiate a "no-cost" contract with the state for the beneficial use of flue gas desulfurization (FGD) material for the reclamation of this site. AEP will bear the costs associated with the reclamation project.

Conesville FGD product is being used to eliminate a dangerous 100-foot highwall and acid mine water runoff from the coal pit at the base of the highwall. FGD will be used to backfill the highwall to the approximate original contour and to seal the pit floor and any auger holes, thereby allowing the mine to fill with groundwater that eliminates oxygen from reacting with the water to form acid mine drainage. The reclamation also includes construction of diversion ditches and installation of two groundwater monitoring wells.

Chet Vance supervises Conesville Power Plant´s landfilling of the coal combustion products -- fly and bottom ash -- generated by the power plant´s six units and FGD product from the power plant´s units 5 and 6 scrubbers. While ash and FGD material are marketable products, the power plant generates more than can be sold for beneficial purposes. Unsold products go to the plant´s active landfill -- a 47-acre, four-phase site southeast of the plant.

This pit and several others like it are the visible reminder that the lands were once surface mined for coal. Prior to the 1977 surface mine reclamation law, mine operators left highwalls exposed, and reclamation simply meant planting trees. The 1977 law requires mining companies to remove all structures and return the land to its original or better condition. Reclamation of abandoned surface mines creates some challenges usually not encountered at active mine sites. In normal surface mine reclamation, the work is done right behind the mining operation, which begins with the removal of vegetation, topsoil and remaining materials. The topsoil is set aside for later use in the reclamation process. In this case, topsoil has to be found.

Eliminating the acid mine drainage involves using approximately 1.6 million tons of FGD material produced by the Conesville scrubbers to backfill the highwall. When the backfilling is done, the area will be graded to its original contour, topsoil replaced and reseeded.

Morrow estimates it will take approximately four years to complete the final reclamation of the site.

"We´re just now getting a good start," he said.

ODNR is enthusiastic about the overall potential, Morrow said. This is the largest project utilizing FGD for reclamation of abandoned mine lands in the state thus far.

Randy Miller, Conesville Prep Plant superintendent, views this beneficial use of a waste product as an excellent example of partnering with the power plant and the state of Ohio. This project results in environmental improvement and a significant cost savings to the company.