Hydrogeology, Groundwater Flow, and Groundwater Quality of an Abandoned Underground Coal-Mine Aquifer, Elkhorn Area, West Virginia
Total Page:16
File Type:pdf, Size:1020Kb
Hydrogeology, Groundwater Flow, and Groundwater Quality of an Abandoned Underground Coal-Mine Aquifer, Elkhorn Area, West Virginia This report was prepared by the U.S. Geological Survey in cooperation with the West Virginia Department of Environmental Protection, the West Virginia Department of Health and Human Resources, and the West Virginia Geological and Economic Survey By Mark D. Kozar, Kurt J. McCoy, James Q. Britton, and Bascombe M. Blake, Jr. U.S. Department of the Interior, U.S. Geological Survey W.Va. Department of Commerce, Geological and Economic Survey 2012 Bulletin B-46 1 Kozar, M.D., McCoy, K.J., Britton, J.Q., and Bascombe M. Blake, Jr., 2012, Hydrogeology, Groundwater Flow, and Groundwater Quality of an Abandoned Underground Coal-Mine Aquifer, Elkhorn Area West Virginia: Morgantown, West Virginia, West Virginia Geological and Economic Survey, Bulletin Number B-46, 103 pages; copies of this report may be obtained by contacting the West Virginia Geological and Economic Survey at 304-594-2331. Mark D. Kozar, Hydrologist U.S. Geological Survey 11 Dunbar Street Charleston, WV 15301 Kurt J. McCoy, Hydrologist U.S. Geological Survey 1730 East Parham Road Richmond, VA 23228 James Q. Britton, Geologist and Bascombe M. Blake, Jr., Manager Coal Programs and Associate Director W.Va. Department of Commerce, Geological and Economic Survey Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted material contained within this report. The picture on the cover of this report was taken by Kurt J. McCoy and is of the Ashland Company Store in Ashland, West Virginia. The original company store was built in the early 1900s, but was destroyed by fire in 1943. The existing store was built shortly thereafter and still exists today. The store is a local landmark and is characteristic of many similar stores owned and operated by coal companies to provide food, clothing, hardware and other day to day necessities for their employees due to inaccessibility by highways of many of the coal mining towns. ii Contents Conversion Factors .................................................................................................................................... ix Abstract ........................................................................................................................................................1 Introduction ..................................................................................................................................................2 Purpose and Scope .......................................................................................................................................2 Description of Study Area ............................................................................................................................3 Approach .....................................................................................................................................................4 Acknowledgements ......................................................................................................................................5 Hydrogeology ..............................................................................................................................................5 Previous Hydrogeologic Investigations .......................................................................................................6 Geology ........................................................................................................................................................8 Stratigraphy ..................................................................................................................................................9 Petrography ................................................................................................................................................12 Thin-Section Analyses ...............................................................................................................................12 Petrographic Results ..................................................................................................................................16 Structural Geology .....................................................................................................................................17 Borehole Geophysical Methods .................................................................................................................18 Results of Borehole Geophysical Logging ................................................................................................18 Hydrology ..................................................................................................................................................19 Groundwater Levels ...................................................................................................................................20 Groundwater Recharge ..............................................................................................................................22 Hydraulic Properties ..................................................................................................................................24 Aquifer Tests ..............................................................................................................................................25 Straddle-Packer Tests ................................................................................................................................ 26 Base-Flow Surveys ................................................................................................................................... 28 Hydrologic Conditions .............................................................................................................................. 29 Groundwater Withdrawals ........................................................................................................................ 30 Dye Tracer Tests and Analyses ................................................................................................................. 30 Results of Tracer Tests .............................................................................................................................. 31 Groundwater Flow .................................................................................................................................... 32 Conceptual Model of Groundwater Flow ................................................................................................. 32 Numerical Model of Groundwater Flow ................................................................................................... 35 Design and Assumptions ........................................................................................................................... 35 Spatial Discretization ................................................................................................................................ 35 Boundary Conditions .................................................................................................................................38 Model Calibration ......................................................................................................................................40 Calibration Procedure ................................................................................................................................40 Calibration Data .........................................................................................................................................41 Parameter Sensitivity .................................................................................................................................42 Model Calibrated Parameters .....................................................................................................................45 Recharge ....................................................................................................................................................45 Horizontal Hydraulic Conductivity ...........................................................................................................48 Vertical Hydraulic Conductivity ................................................................................................................51 Drain and Riverbed Conductance ..............................................................................................................51 Simulated Flow for the 70th Percentile Flow Duration .............................................................................52 iii Water Budgets ............................................................................................................................................52 Groundwater-Flow Directions ...................................................................................................................53 Simulated Flow for the 87th Percentile Flow Duration ............................................................................55 Water Budgets ............................................................................................................................................55 Interbasin Transfer .....................................................................................................................................55