After reclamation, slopes should be a uniform, or smooth shape. Concave slopes may retain too much water and not drain properly. Convex slopes may cause water to run off the slope causing erosion issues. (VIP 8) Again, from the DSM that was generated from the satellite imagery, a slope shape or curvature map can be created using appropriate tools in a GIS. This process returned results consistent with the current slope shape at the site. The figure below shows three slope shape categories for the regraded area outlined in red. Concave shapes are represented in red, convex shapes are in blue and uniform shapes are in yellow. The inspector can use this map to identify concave or convex slopes and target those areas for field inspection to determine if the slopes conform to the requirements in the permit or require further remediation.
Slope Shape (curvature) at McKinley mining site.