Geomorphic Approaches to Reclamation of Abandoned Coal Mine Slurry Impoundment Closure

Marketing Paragraph: Statement of Purpose: In our evolving world, health, environmental, and economic challenges are growing. Creating sustainable engineering solutions to meet the world's demands has been my passion, which I was able to fulfill through my studies and research at WVU. My research work explores geomorphic landform design (GLD) as a potential reclamation approach for coal impoundments in West Virginia, USA. GLD is considered a promising reclamation approach for designing and building earthen structures based on what would naturally occur to the land under climatic conditions. Employing GLD rather than conventional reclamation approaches is more environmentally friendly. GLD creates stable stream channels as it takes into consideration different climatical factors, such as rainfall. I have investigated the difference between the conventional reclamation approach and GLD in terms of hydrologic response, material, and slopes required to create the designs.
The research intended to determine whether applying the principles of GLD to coal slurry impoundment structures would generate designs that are hydraulically balanced, stable, and less material demanding. A series of conceptual reclamation designs were completed for a coal slurry impoundment in Monongalia County, WV, USA. Earthwork balance and hydrologic response analyses were conducted on the created designs. Natural Regrade® and Hydrology Modules from Carlson were used to develop these fluvial geomorphic conceptual designs and evaluate the hydrologic response. AutoCAD Civil 3D was utilized to determine the amount of material needed to achieve each design. AutoCAD Civil 3D was also used to conduct slope analysis.
I am beyond thrilled to share more interesting information about this topic by attending the IECA Annual Conference to engage with a community of passionate individuals.

Full Abstract: Complete Proposal for Your Session: Coal Refuse impoundments are coal waste collection basins located between adjacent mountains built by damming rocks and coarse coal refuse generated during mining. The coal mining industry uses coal refuse impoundments for the disposal of fine coal refuse (FCR) slurry. As FCR has particle size about the same as silt, it is associated with weak strength and relatively low permeability. It is possible in some cases that the FCR slurry could turn into a viscous fluid that can build pressure against the dam containing it, resulting in failure. Regulations have been created to govern impoundment construction and closure, and reclamation was integrated into the process for post-mining land use establishment.

The overall goal of the current research work was to apply the geomorphic landform design (GLD) principles to a coal mine slurry impoundment structure located in Monongalia County, West Virginia, USA, to generate a design that is stable, hydraulically balanced, aesthetically appealing, and less filling material demanding. A series of geomorphic designs were created and later submitted to slope analysis, earthwork balance, and hydrologic response analyses. The geomorphic designs were compared to a conventional plan.
The geomorphic approach to reclaiming the reservoir area generated uniform contour lines that resulted in less backfill material needed for the design compared to the conventional reclamation approach. However, no substantial difference in peak runoff discharge was observed when comparing the hydrologic response of the created designs. Expanding the area of disturbance to surrounding ridgeline with high elevations required more filling material and tributaries, which may create some slope instability on the hillside. Accordingly, a small disturbance area covering the reservoir was recommended. The final conclusions of the research indicated that overall, complete GLD may not be a viable option as compared to the traditional impoundment closure process. Nevertheless, the option that combined conventional approaches with GLD principles (Model: Convention-GLD) demonstrated some benefits. Conventional-GLD reclamation added slope complexity within the disturbed area with all slopes of 3:1 or less, which suggests overall stability. When compared to the conventional design for 100-year and 500-year events, Conventional-GLD had lower peak discharges and longer times to peak discharges. Fill requirements were minimized with the Conventional-GLD option as well.