Topographic reconstruction through geomorphic approach for preliminary reclamation: Caballo mine, Wyoming

Abstract

Mining is an important undertaking to support local and global economies. However, most mining operations unavoidably lead to substantial environmental damage. After the mining activity is complete, suitable reclamation policies are applied to post-mining areas. Whenever possible, reclamation activities are implemented while mining operations continue. The traditional approach to topographic reconstruction primarily consists of the grading and shaping of waste rock. Slopes and stream channels are constructed without much thought concerning their integration into functional drainage catchment areas as open, process response systems. Unfortunately, traditional reclamation can be costly and have unintended consequences on the environment. The objective of this study was to test the hypothesis that geomorphic reclamation is a more cost-effective approach and has less adverse impacts on the surrounding environment. To test the hypothesis, a geomorphic reclamation approach was applied on a small northern section of Caballo mining, Wyoming. Geomorphic reclamation is proposed as an alternative to the common traditional reclamation. A Digital Elevation Model was constructed and processed in ArcGIS software to investigate comparative characteristics among the study area (traditional reclamation landscape), a reference area for the reclamation, and the new reconstructed landscape (geomorphic approach). The overall goal is to generate a geomorphically reclaimed landscape that mimics the natural features of the surrounding area and estimate the cost that is associated with material volume. The number of drainage-catchment areas, average mean slope, and the number of drainage networks for the reference surrounding area is closely replicated in the reconstructed topography. After those adjustments, the reclamation surface became more reflective of the design. The difference in elevation created between the topography of the study area and the reconstructed landscape was manipulated to give a material volume difference of the topographies. The cost of reclamation was then estimated from the amount of material to be moved to achieve that topography. The geomorphic reclamation results indicate an efficient mining reclamation alternative to the traditional approach.