Evaluating Changes in Freshwater Quality Using Groundwater Monitoring Wells in Areas of Natural-Gas Development

Impairment of groundwater quality in areas of shale gas extraction has been reported, although causes remain unclear and contested due to inadequate baseline (pre-drill) water-quality data and insufficient knowledge of legacy contamination, industry operations, and local hydrogeology. To help address this issue, we are making chemical and hydrological measurements in freshwater aquifers and streams in Susquehanna County, PA. Through analysis of these measurements, we intend to (i) elucidate the spatial and temporal variations in trace metal concentrations, major ions concentrations, hydrocarbon concentrations, and isotope chemistry prior to commencement of gas extraction activities; (ii) quantify perturbations in groundwater flow that occur naturally or that are attributable to any step in the process of shale gas development; and (iii) evaluate changes (if any) in groundwater chemistry and isotopic composition induced by hydraulic fracturing and other stages of shale gas extraction.