Numerical Analysis of Groundwater Quality Impacts from Hydraulic Fracturing Wellbore Leakage

The development of directional drilling and stimulation of reservoirs by hydraulic fracturing makes it economically feasible to recover unconventional oil and gas resources from shale formations, coal beds, and tight sand reservoirs. Hydraulic fracturing presents a set of water-quality challenges, including increased competition over water resources and the potential for air, surface water, and groundwater contamination. In this project, we use a three-dimensional, multiphase, multicomponent numerical model to investigate hydrogeologic conditions that could lead to groundwater contamination from a leaking hydraulic fracturing wellbore. We find that groundwater contamination resulting in impact to human health and the environment varies as a function of heterogeneity in subsurface permeability. Also, we describe a scenario where methane may serve as a precursor to contamination of drinking water aquifers by brine.