Department of Civil and Environmental Engineering, The Pennsylvania State University , 212 Sackett Building, University Park, Pennsylvania 16802, United States.
Department of Ecosystem Science and Management, The Pennsylvania State University , 116 Agricultural Sciences and Industries Building, University Park, Pennsylvania 16802, United States.
Environ Sci Technol. 2017 Aug 1;51(15):8851-8860. doi: 10.1021/acs.est.7b01696. Epub 2017 Jul 12.
Combining horizontal drilling with high volume hydraulic fracturing has increased extraction of hydrocarbons from low-permeability oil and gas (O&G) formations across the United States; accompanied by increased wastewater production. Surface water discharges of O&G wastewater by centralized waste treatment (CWT) plants pose risks to aquatic and human health. We evaluated the impact of surface water disposal of O&G wastewater from CWT plants upstream of the Conemaugh River Lake (dam controlled reservoir) in western Pennsylvania. Regulatory compliance data were collected to calculate annual contaminant loads (Ba, Cl, total dissolved solids (TDS)) to document historical industrial activity. In this study, two CWT plants 10 and 19 km upstream of a reservoir left geochemical signatures in sediments and porewaters corresponding to peak industrial activity that occurred 5 to 10 years earlier. Sediment cores were sectioned for the collection of paired samples of sediment and porewater, and analyzed for analytes to identify unconventional O&G wastewater disposal. Sediment layers corresponding to the years of maximum O&G wastewater disposal contained higher concentrations of salts, alkaline earth metals, and organic chemicals. Isotopic ratios of RaRa and SrSr identified that peak concentrations of Ra and Sr were likely sourced from wastewaters that originated from the Marcellus Shale formation.
在美国，水平钻井与大规模水力压裂技术相结合，提高了低渗透油藏和天然气（O&G）地层的碳氢化合物开采量；同时也增加了废水的产生。集中废水处理（CWT）厂将 O&G 废水排入地表水，对水生生物和人类健康构成了威胁。我们评估了宾夕法尼亚州西部康内马格河湖（大坝控制水库）上游的 CWT 厂处理的 O&G 废水对地表水的影响。收集了监管合规数据来计算每年污染物排放量（Ba、Cl、总溶解固体（TDS）），以记录历史工业活动。在这项研究中，距离水库上游 10 和 19 公里的两个 CWT 厂在沉积物和孔隙水中留下了地球化学特征，反映了 5 至 10 年前的工业活动高峰。对沉积物岩芯进行了分段，以收集沉积物和孔隙水的成对样本，并对分析物进行分析，以确定非常规 O&G 废水的处理方法。对应于最大 O&G 废水处理年份的沉积物层含有更高浓度的盐、碱土金属和有机化学品。RaRa 和 SrSr 的同位素比值表明，Ra 和 Sr 的峰值浓度可能来自源自马塞勒斯页岩地层的废水。
