Surface Mine Permitting
Centre County, PA
Groundwater impact assessment and permitting modules
Our client was seeking to deepen an existing quarry and to extend surface mining laterally from an existing quarry. The site is located upon karstic (subject to the formation of sinkholes and caves) limestone bedrock upslope from a fish hatchery and a high-quality trout stream. Pennsylvania Department of Environmental Protection (PADEP) required a groundwater impact assessment for the deepening activity and the lateral expansion project.
Converse met with PADEP staff, who initially presented a requirement that the site be modelled using a numerical aquifer simulation model such as ModFlow. Converse made the case that the site setting was too complex to be suitable for numerical modelling and proposed an innovative / alternative method to use existing data and judgment-based, graphical methods to evaluate dewatering and groundwater impact conditions. Converse prepared the hydrogeologic permitting module information for the lateral expansion activity.
This project has involved interaction with citizens, local government to address identified concerns. Local government expressed specific concerns that the expansion quarry activity would impact a bordering “phantom lake” (polje), for which Converse developed a separate impact assessment.