Water Resources Research Act Program

Details for Project ID 2017PA233B

Impact of Spreading Oil & Gas Wastewater as Road Treatments on Water Quality

Institute: Pennsylvania
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $19,997 Total Non-Federal Funds: $43,298

Principal Investigators: William Burgos

Abstract: Spreading conventional oil and gas (O&G) wastewaters to treat roads is common, legal, and represents an immediate risk to water resources in northwestern PA. This is of great concern because of the chemical and contaminant characteristics of conventional O&G wastewaters. Flowback and produced waters are typically hypersaline and contain a variety of organic, inorganic, and radioactive contaminants [1, 2, 6, 7]. In northwestern PA, conventional O&G wastewaters are spread directly on roads for both de-icing and dust suppression under existing regulations. However, spreading conventional O&G wastewaters on roads threatens neighboring groundwater and surface water quality. The objective of this project is to investigate if spreading conventional O&G wastewater on Pennsylvania roads for dust suppression is impacting water resources. File reviews at the Pennsylvania Department of Environmental Protection (PADEP) Northwest Regional Office (Meadville, PA) will be expanded to identify the exact roads with the greatest amounts of current and historical spreading of O&G wastewater. Working with PADEP and local municipalities, 10-12 samples of O&G wastewater currently used for road treatments will be collected. Working with the Center for Dirt and Gravel Roads at Penn State, samples of unused road aggregate and subgrade material will be collected from municipalities in northwestern PA. The O&G wastewaters will be fully characterized by measuring organic (by GC-FID), inorganic (by ICP-OES), and radioactive (by gamma spectroscopy) contaminants. The O&G wastewaters will be reacted with road aggregate and subgrade material to evaluate the potential for contaminant mobilization following the Synthetic Precipitation Leaching Procedure (SPLP; EPA Method 1312). Results from the SPLP measurements for each O&G wastewater sample will be compared to leachate concentration limits for dust suppressants. The transport of contaminants of concern (identified by the SPLP measurements) from the roadway to neighboring water resources will be modeled using a commercially available groundwater transport model. One of the O&G wastewaters will be reacted with road aggregate and subgrade material to measure contaminant partition coefficients (i.e., Kd). This O&G wastewater sample will be used in column experiments to measure contaminant transport properties and compare with model results based on the batch-derived Kd values. Effluent samples will be collected as a function of time and analyzed for the contaminants as described above. Column effluent data will be modeled to calculate contaminant retardation coefficients. The groundwater transport model will be used to predict contaminant concentrations as a function of time at a distance of 150 feet from the road, the regulated distance from a road spreading location to surface water.