The impact of unconventional oil and gas development on water quality is a major environmental concern. We built a large geocoded database that combines surface water measurements with horizontally drilled wells stimulated by hydraulic fracturing (HF) for several shales to examine whether temporal and spatial well variation is associated with anomalous salt concentrations in United States watersheds. We analyzed four ions that could indicate water impact from unconventional development. We found very small concentration increases associated with new HF wells for barium, chloride, and strontium but not bromide. All ions showed larger, but still small-in-magnitude, increases 91 to 180 days after well spudding. Our estimates were most pronounced for wells with larger amounts of produced water, wells located over high-salinity formations, and wells closer and likely upstream from water monitors.

非常规油气开发对水质的影响是一个主要的环境问题。我们建立了一个大型地理编码数据库，该数据库将地表水测量值与由水力压裂 (HF) 刺激的几个页岩水平钻井相结合，以检查时间和空间井变化是否与美国流域的异常盐浓度有关。我们分析了四种离子，它们可以表明非常规开发对水的影响。我们发现钡、氯化物和锶的新 HF 井的浓度增加非常小，但溴化物没有。所有离子都显示出更大，但仍然很小，在开井后 91 至 180 天增加。我们的估计对于采出水量较大的井、位于高盐度地层上的井、