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Excess spoil disposal |
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Before passage of the Surface Mining Law in 1977, it was a common practice in steep-sloped areas of Appalachia to dispose of excess spoil by pushing it down the mountain. Under the Surface Mining Law excess spoil is permanently stored in engineered spoil fills. This fill, located in Eastern Kentucky, was constructed in a series of terraces along the contour to minimize infiltration of surface water into the fill material. The drainage flows into riprapped diversion ditches that minimize soil erosion as the water flows into the sedimentation pond at the base of the fill. Enlarged Photo (66 KB file)
This is the same head-of-hollow fill as shown in the photo above. The photo above was taken during the reclamation stage of the operation and this photo was taken six years later, after the reclamation bond had been released and the property was being used by the land owner. Comparing these two photos it can be seen that the sedimentation pond at the base of the fill has been retained as a permanent impoundment. Today the landowner has created a park-like setting that is used for fishing and picnicking. All water runoff from the fill is free of sediment and native tree and shrubs are becoming established on the fill. Enlarged Photo (65 KB file)
The presence of excess volumes of hard, durable rock on some mine sites make end-dumping of the spoil an economical way of placing excess spoil in fills. Gravity segregation ensures that large rocks reach the bottom of the fill to form a layer of freely draining rock similar to a French drain. Fine-grained, poorly draining rock and soil are trapped at the top of the slope where they are unlikely to affect the fill's long-term stability. Enlarged Photo (61 KB file)
The Head-of-hollow fill at this Kentucky mine operation has just been completed and revegetation is beginning. The mine operator has retained some of the natural forest land adjacent to the fill and blended the slopes to form a broad swale across the valley. The rock lined drains on each side of the fill carry water from the surrounding area down the slope without causing soil erosion or water infiltration into the rock structure. Enlarged Photo (61 KB file)
Experimental Practice becomes an award winning project
Working together, the Kentucky Department of Surface Mining Reclamation and Enforcement and the Office of Surface Mining approved the Stone Mining Company Experimental Practice that transformed a coal slurry impoundment into the Grants Branch Lake...a fishing lake/mountain resort facility in Pike County, Kentucky. The Experimental Practice allowed alternative requirements of the Surface Mining Law so the slurry impoundment could be left as a permanent structure. Under the Experimental Practice, the company created a recreational lake in lieu of covering the slurry impoundment with the required four feet of non-toxic earth material..
Enlarged Photo (40 KB file)
Coal Refuse Impoundment
The Stone Mining Company began using the impoundment in 1968. Coal refuse generated at an adjacent cleaning plant was deposited behind the large embankment. The original permit required that the slurry pond be reclaimed to a post-mining land use of forest land and industrial/commercial use. The success for this post-mining land use was based on completely filling the impoundment with slurry, and when the plant supplying slurry to the impoundment ceased operation other reclamation alternatives were examined. Working with the county government, a plan was developed to reclaim the site into a recreation area that would directly benefit the community. The Experimental Practice was approved in 1997 and work began converting the coal slurry impoundment into a water resources recreational facility. Enlarged Photo (21 KB file) Photo Credit: Stone Mining Company
Modifications to the structure
The elevation of the spillway was raised and the height of the embankment lowered in order to create usable flat land at the top and reduce the down stream slope of the dam. The entire face of the dam was covered with more than two feet of soil and grass was planted. Today the lake is approximately 21 acres and has 6,200 feet of shoreline. Stocked with more than 10,000 fish, it's a serene, peaceful setting complete with paved roads, parking, and picnic areas. When final bond is released, the land will be transferred to the county as a permanent public reclamation area.
Enlarged Photo (35KB file) Photo Credit: Stone Mining Company
The spillway from the lake cascades through a man-made rock gorge
The Grants Branch Lake and Recreation Facility has been recognized as a unique solution to the reclamation of a slurry pond. It has received the 1999 Governor's Environmental Excellence Award in Mining Reclamation- Eastern Kentucky, the 1999 Best Reclamation Award from the Pikeville Regional Office (jointly presented by the Kentucky Division of Surface Mining Reclamation and Enforcement and the Kentucky Coal Association), an Honorable Mention Award from the Interstate Mining Compact Commission, and a National Reclamation Award from the Office of Surface Mining.
Enlarged Photo (46KB file)
