Dr. Nathan Epler is a Principal-Level Hydrogeologist, having over 33 years of experience in site assessment, site remediation, chemical fate and transport evaluations and as an environmental expert witness. Dr. Epler has extensive expertise in evaluating the timing of releases, geochemistry and the fate and transport of environmental contaminants in soil, soil vapor, and groundwater, including emerging contaminants, pesticides and herbicides, light non-aqueous phase liquids (LNAPLs) and dense nonaqueous phase liquids (DNAPLs), in unconsolidated and bedrock aquifers. Dr. Epler has managed remedial investigations at major industrial facilities, petroleum refineries, Manufactured Gas Plant and Brownfield redevelopment sites throughout the United States. He has designed and supervised the installation of large-scale remedial systems at Superfund Sites throughout the northeast. He has experience in the computer modeling of groundwater flow and contaminant transport at Federal Superfund sites, large petroleum terminal and industrial Sites, including sites impacted by mixed plumes of volatile organic compound (VOC) contamination, and has a proven track record of obtaining Site closure.