Background  High-salinity mine water (HSMW) is widely distributed in mining areas in western China, while its discharge and treatment pose severe challenges to both the ecosystem and resource utilization. In recent years, HSMW storage in deep strata has gained widespread attention as an environmentally friendly and resource-saving approach for mine water treatment.

Advances  Focusing on the general characteristics of HSMW, this study systematically reviewed the key scientific issues and technical bottlenecks associated with HSMW storage in deep strata, highlighting its principles, technical classification, and engineering application. It comprehensively elucidated the applicability boundaries of this technology, involving the core links such as geological condition assessment, injection well design, water quality pretreatment, process monitoring, and storage stability evaluation. Additionally, this study proposed a method for selecting deep reservoir horizons for HSMW storage from the perspective of four characteristics: regional structures, basic geology, physical properties of reservoirs and caprocks, and hydrogeological conditions. The design principles of injection well structures were defined by integrating three factors: safety and environmental friendliness, injection efficiency, and economic feasibility. Furthermore, this study clarified the advantages and limitations of techniques for HSMW pretreatment, along with mine water quality requirements for reinjection. Accordingly, this study established a whole-process dynamic monitoring system for HSMW reinjection and developed a multi-physics coupling-based method for the stability evaluation of mine water storage. In addition, the limitations of existing technologies were further summarized, such as scaling, corrosion, geological disturbances, and potential environmental risks.

Prospects Future development of HSMW storage in deep strata should focus on efficient, low-consumption water treatment technologies, scaling and corrosion prevention systems, assessment of geological environmental impacts, and the improvement of relevant policies and regulations. The purpose is to provide a scientific basis for establishing a new paradigm of low-carbon mine water treatment. HSMW storage in deep strata facilitates water resource recycling while addressing the issue of mine water discharge, providing significant environmental and economic benefits. Driven by continuous breakthroughs in efficient, low-consumption treatment techniques and novel functional materials, HSMW storage in deep strata will develop toward standardization, intelligence, and greening.