Capacity characteristics of the underground water reservoir of an open-pit coalmine: a case study in Baorixile

Abstract

Water storage capacity has always been the core component of the underground water reservoir in open-pit coalmines. Taking the western underground water reservoir of Baorixile open-pit coalmine as the research background, boreholes in the waste dump overlying the underground water reservoir were designed and drilled, and the capacity characteristics of the underground water reservoir were studied by a layered summation method. These test results revealed that: (1) the regional strata from shallow to deep are the near-surface loose layer, upper bench loess, mixed stripping material, glutenite water reservoir layer and rubble collecting ditch; and the glutenite water reservoir layer is the main water storage body of the underground water reservoir. (2) Permeability coefficient, porosity, layered and cumulative water storage of the western underground water reservoir in Baorixile open-pit coalmine increase with the elevation increase, and show a quadratic function relationship. (3) The total storage capacity of the underground water reservoir is 1.2234 Mm3, and the average porosity is 0.1003, that is, each volume of the water storage medium can store 0.1003 volume of water. These results provide a scientific basis for the evaluation and determination of the water storage capacity of the underground water reservoir in open-pit coalmines. HIGHLIGHTS The design and construction of the underground reservoir in Baorixile open-pit coalmine.; A calculation method of underground reservoir capacity in open-pit coalmines based on a field borehole water injection test.; The reservoir capacity characteristics of the western underground reservoir of Baorixile open-pit coalmine.;

Keywords

• permeability coefficient
• porosity
• underground water reservoir
• water injection test
• water storage capacity