The rapid expansion of shale gas development has revolutionized global energy markets, yet it has also introduced substantial environmental challenges, particularly concerning groundwater resources. This comprehensive review systematically examines the multifaceted impacts of shale gas extraction on groundwater, with a focus on contamination mechanisms, pollutant sources, and mitigation strategies. The study identifies key operational stages—exploration, drilling, hydraulic fracturing, and flowback—as potential sources of groundwater contamination. Inorganic pollutants, including heavy metals and radionuclides, as well as organic compounds such as hydrocarbons and chemical additives, are identified as primary contaminants. The review critically evaluates current wastewater treatment technologies, including reinjection, internal reuse, and advanced desalination methods, highlighting their efficacy and limitations. Additionally, the study proposes a refined environmental management framework that integrates wellbore integrity optimization, enhanced shale gas wastewater treatment, and stringent monitoring protocols. The adoption of clean fracturing technologies and renewable energy applications is recommended to minimize environmental footprints. By establishing comprehensive baseline data and robust pollution monitoring systems, this research provides a scientific foundation for sustainable shale gas development, ensuring the protection of groundwater resources. This review emphasizes the imperative of balancing energy security with environmental sustainability, offering actionable insights for policymakers, industry stakeholders, and environmental scientists.

We characterized horizontal hydraulic conductivity (K) of a fractured granitic aquifer using single‐ and cross‐hole hydraulic tests to evaluate “scale effect.” For selected boreholes, K estimates were obtained using single‐hole FLUTe liner and slug tests. Several cross‐hole pumping tests were carried out at various durations. Drawdown responses were first interpreted using analytical well‐test solutions to obtain an effective horizontal conductivity (K_eff) assuming a homogeneous and infinite aquifer. The same drawdowns were then numerically inverted using transient hydraulic tomography (THT) to delineate spatial distributions of K and storativity in the area encompassing the boreholes. Papadopulos (1965) and a nonlinear least squares minimization method produced a similar principal K_eff direction that is consistent with the dominant fracture strike observed from outcrop and borehole televiewer data. However, principal direction and magnitude of this K_eff depend on the pumping test duration and the number of monitoring boreholes used in the interpretation. As a group, K obtained from cross‐hole tests is larger than that obtained from single‐hole tests. However, because cross‐hole tests stressed the aquifer at both interwell and larger scales, K_eff obtained from interpreting cross‐hole data is observed to decrease with pumping time, likely due to the dominance of less permeable fractures at larger scale. This lateral reduction of mean K is also revealed by THT as low K zones surrounding the test boreholes. Overall, K is found to increase from single‐hole to the interwell scale and then decrease at larger scale, exhibiting a non‐monotonic scale effect.