Date of Graduation

2016

Document Type

Thesis

Degree Type

MS

College

Statler College of Engineering and Mineral Resources

Department

Civil and Environmental Engineering

Committee Chair

John D Quaranta

Committee Co-Chair

Leslie Hopkinson

Committee Member

Vladislav Kecojevic

Abstract

This research was aimed at implementation of Geomorphic Landform Design (GLD) principles to the Royal Scot abandoned coal refuse disposal facility in Greenbrier County, West Virginia, USA. This facility currently exhibits many undesirable environmental problems including acid-mine drainage and significant erosion and sediment transport.;A multi-layer cap and cover system in conjunction with GLD principles was proposed as a solution to these environmental problems. This cover is proposed to be constructed from the coarse coal refuse material on-site and a short paper fiber material (MGro(TM)) from the MeadWestVaco paper mill in nearby Covington, Virginia, USA. To determine the possible effectiveness of this design, multiple research stages were completed. First, the principles of GLD and landform covers were investigated, as well as the use and properties of coarse coal refuse combined with short paper fiber. Second, a suite of geotechnical laboratory testing was completed on the materials to be used in the construction. Third, the cap and cover system was designed based on the measured geotechnical parameters. Fourth, the cap and cover system was applied to three reclamation alternatives and its seepage control performance and geotechnical stability were analyzed by the finite element method (FEM) for slope stability and seepage using SVFlux(TM) and SVSlopeRTM computer modeling software.;Geotechnical testing results concurred with literature and tended to indicate that blending short paper fiber at 40 percent with 60 percent coarse coal refuse (volumetric ratio); along with layers of 100% coarse coal refuse at Royal Scot could make an effective cap and cover system. Short paper fiber is a suitable growth media in literature and laboratory testing of a MGro(TM) and coarse coal refuse blended (60/40) material indicated a suitably strong material with an internal angle of friction of approximately 30°. The coarse coal refuse shale material (100%) had a friction angle of 40° with hydraulic conductivity values of 10-6 to 10-7 cm/s when compacted to standard proctor effort. Constructing a cover with a 0.915m (3 ft) thick 60/40 MGro / coarse coal refuse growth layer, a 0.915m (3 ft) thick drainage layer of loose coal refuse, and a 0.915 m (3 ft) thick layer of compacted coal refuse. The total cap thickness was 2.75 m (9 ft) which produced a cover system capable of reducing seepage into the underlying acid-generating fill by 85%. The cap and cover system was stable on slopes up to 21.8°.;FEM stability modeling indicated that the cover design could be applied to a design of the Royal Scot re-graded to geomorphic profiles. The design was stable, with a geotechnical factor of safety over the required minimum 1.5 on slopes less than or equal to 21.8°. Additionally, seepage into the acid-generating fill was shown to be reduced by nearly 75%. With the addition of internal drains, which will be required on shallower slope benches of the reclamation to reduce the accumulation of internal pore water pressure, the seepage reduction was further reduced by 10%, which is a nearly 85% reduction of infiltration.

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