Water Resources Research Act Program

Details for Project ID 2017NC211B

Tracing Groundwater Contamination Near And Away From Coal Ash Ponds in North Carolina

Institute: North Carolina
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $49,993 Total Non-Federal Funds: $29,495

Principal Investigators: Avner Vengosh

Abstract: Recent discovery of elevated hexavalent chromium and vanadium concentrations in drinking water wells near coal ash ponds has triggered public concerns about the possible migration of coal ash contaminants to aquifer systems adjacent to coal ash-holding ponds in NC. Previous studies have demonstrated that coal ash effluents contain elevated levels of contaminants, and their migration to the environment could increase human health and environmental risks. This proposed study seeks to evaluate the occurrence of toxic contaminants in drinking water wells near and away from coal ash ponds in two focal sites in Salisbury and Belmont, NC, evaluate possible migration of coal ash effluents to the underlying aquifers, and establish reliable geochemical and isotopic criteria combined with hydrogeological data for distinction between naturally occurring and anthropogenic contamination specifically derived from coal ash ponds leaking. The proposed project consists of (1) generating a new geochemical and isotopic database of about 150 drinking water wells near and away from coal ash ponds in Salisbury and Belmont; (2) drilling new monitoring wells for characterization of the hydrogeology, groundwater gradients, and the quality of shallow groundwater adjacent to coal ash ponds; and (3) integrating new and existing water quality databases for drinking water wells, shallow groundwater underlying coal ash ponds, and baseline datasets in NC. The overall objectives of this study are (1) to provide a scientific evaluation of the occurrence and origin of toxic elements such as hexavalent chromium and vanadium in drinking water wells and associated risks to homeowners in affected areas in NC, and (2) determine if coal ash contaminants are indeed migrating to the aquifers near coal ash ponds. The proposed study is based on a wide spectrum of analytical tools including hydrogeology, water quality with high precision detection of hexavalent chromium and vanadium, aquatic geochemistry, and multiple isotopic tracers including oxygen, hydrogen, carbon, boron, lithium, and strontium isotopes. We have already identified drinking water wells and established communication with homeowners in the two research areas, followed by conducting preliminary sampling and establishing an initial dataset of water quality in the two research sites in order to demonstrate our capability to conduct this study. The outcome of this proposed study will be highly beneficial for homeowners who use private wells as their major drinking water source in areas near and away coal ash ponds, as well as state officials for helping to evaluate the human health risks associated with the water quality and in particularly the highly toxic hexavalent chromium in aquifers of North Carolina.