Coupling geochemistry and real-time water quality sensing for identifying and quantifying basin brine and road salt sources in watersheds along the New York Pennsylvania border

The following chapters explore coupled geological and hydrological tracers which can be used to identify basin brine and road salt sources in surface and ground waters in watersheds along the New York and Pennsylvania border. They attempt to further our understanding of geochemical fingerprints which can be used to identify and quantify sources, as well as to characterize regional baseline conditions prior to development of natural gas resources from the Marcellus Shale using horizontal drilling techniques. In chapter one, Cl/Br and (Ba+Sr)/Mg ratios were used to distinguish between brine sources in streams, and when integrated with groundwater sampling results, indicate pre-existing high total dissolved solids (TDS) sources are prevalent throughout the Upper Susquehanna River Basin. Chapter two identifies several geochemical fingerprints which can be used to identify the Marcellus Shale in comparison to surrounding units from drill cutting waste disposal perspectives. Based on results from water/rock interaction experiments, Pb isotope ratios, Mo, and other trace metals can be used as diagnostic fingerprints for leachate generated from the Marcellus Shale. In chapter three, real-time stream conductivity data was used to detect high TDS inputs into surface water from basin brine and road salt sources. Short and long term perturbations in conductivity from these sources are distinguishable in relation to baseline conditions, and prediction of sonde conductance response to pollutant loading scenarios can be modeled. These chapters indicate that hydrological and geochemical metrics can be used by water resource professionals to characterize sources and water quality conditions pre and post horizontal natural gas drilling in watersheds on local and regional scales.