Spatial and temporal water chemistry variations of hydraulic fracturing flowback and produced waters from the Duvernay Formation

Abstract

Chemical characterization of hydraulic fracturing (HF) flowback and produced water (FPW) is important to the environmental sustainability of HF operations. In this research, we analyzed and compared HF FPW samples from different well locations as well as FPW samples from a single well at different stages of FPW production in the Duvernay Formation using a suite of analytical techniques and statistical methods. The results provide vital information to assess the reusability of FPW and support the choice of water handling, treatment, or disposal options. Additionally, this work contributes to a more complete understanding of regional FPW chemical composition and has the potential to provide guidance on best practices for future applications of HF fluid additives. While reuse of FPW is desirable, it is not always feasible. In these scenarios, the transportation of FPW offsite for treatment and/or disposal increases the risk of spills to near-surface environments. This work provides data to aid spill clean-up efforts and to determine the environmental fate of FPW contaminants. Overall, the information presented in this work may be used to provide economic benefits to the oil and gas sector by increasing FPW reuse that will directly decrease wastewater disposal costs and reduce environmental impacts of HF operations by decreasing the volume of used surface water and the risk of FPW surface spills.