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PRODIGIOUS STREAM RESTORATION, REHABILITATION AND RECLAMATION NEEDS IN THE APPALACHIAN COAL FIELDS. Presentation Complete with Images is Available at http://www.geo.wvu.edu/~kite/2004SENEGSA.htm. J. Steven Kite, Jocelyn Smith & Jennifer Walker West Virginia University .
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PRODIGIOUS STREAM RESTORATION, REHABILITATION AND RECLAMATION NEEDS IN THE APPALACHIAN COAL FIELDS Presentation Complete with Images is Available at http://www.geo.wvu.edu/~kite/2004SENEGSA.htm J. Steven Kite, Jocelyn Smith & Jennifer Walker West Virginia University Mountain-Top Removal & Valley Fill, Kayford Mountain, 1997
Where is Stream “Restoration” Need Greatest? 100 Human Earth Movement: Million Tons/Year for 1° Longitude by 1° Latitude Grid Cells 0 • See Image from: • Hooke, R. L., 1999, Spatial distribution of human geomorphic activity in the United States; • comparison with rivers: Earth Surface Processes and Landforms, v. 24, p. 687-692.
West Virginia Coal MiningProduction (Million Tons) & Employment (Thousands)Modified from Charleston Sunday Gazette-Mail Production SMCRA Employment 2000
Surface Mine Control & Reclamation Act (SMCRA, 1977) Requires Reclamation to Approximate Original Contour (AOC) AOC is Far Removed from Original Landscape Form and Function. Potomac Mine, Elk Run, Grant Co. WV, June 1999
Post-Reclamation Drainage1st and 2nd Order Streams Decapitated from Rest of Drainage Network.
Pre-Miningvs. Post-Reclamation Drainage for Three Surface Mine Sites in Northern WV Decrease in Drainage Density and Integration
1st Order Stream Bed Mobilization on Reclaimed Mine Wastes Minden AML Site,after 115 cm Rainfall, July 2001 NPS Photo
Oversized Rock-Lined Slope-Orthogonal 2nd Order Channel Incapable of Most Stream Functions
Unlined Sub-Horizontal Anthropogenic1st Order “Stream” Designed NOT to Transport Sediment
“Deranged” DrainageStreams Sub-Parallel to Contour Huge (Rock Lined?) Streams Orthogonal to Slope Straight Channels, 90º Intersction Angles Permit Area #80-80, 2002, North Central WV
Stream “Restoration” Issues Related to Reclaimed Contour Surface Mines • Ecological Integrity • Drainage Integration • Bank-Full and Flood Flows? • Sediment Supply & Transport • Natural Stream Design Cost-Benefits vs. Currently Used Structures • Over What Time Frame?
More Prodigious Stream “Restoration” Needs: Mountain-Top Removal and Valley Fill Mountain-Top Removal Valley Fill
“Durable” Rock Valley Fill End-Dump Produces Internal Drainage System Without Chimney Drain Cost
Some Fills Exceed 100 m in Depth (large dump truck for scale) Amherst, WV
Completed Durable Rock Valley Fill>1700 Valley Fillsin WV Up to 195 hectares (480 acres) each >1600 km of Streams Filled in WV
Unfinished Valley FIll Colluvial Slope Photo: K. Paybins, USGS Scour of Unmined Colluvial Slope in Valley Fill “Groin,” July 2001
Scoured Colluvium Valley Fill Groin July 2001 J.S. Kite Photo Valley Fill Colluvium
“Natural” Valley Fill Design? • Materials: • “Durable” Rock May Not Be Available in Quantity • Wrong Geology Yields Bad Fill • Channels & Toeslopes Must Be Armored to Avoid Run-Away Incision • Slope Stability = Critical to Stream Design • Landslides & Debris Flows Exacerbate Floods • Water Flow Must Be Carefully Routed • Groins = Vulnerable Cyprus Kanawha Mine Valley Fills: Completed & Under Construction Photo by Lawrence Pierce, Charleston Gazette, 1998
Stream “Restoration” Issues Related to Valley Fills Habitat Loss & Ecological Integrity Flood & Baseflow HydrographEnhancement or Attenuation? Sediment Supply & Transport Selection of Appropriate Analogs? Pre-SMCRA Mining in Most Watersheds USGS Photo