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With the rapid growth of population and economy, the demand for groundwater resources is also increasing, leading to the exploitation of groundwater in some areas far greater than the recharge, which easily causes a series of environmental geological problems such as groundwater drawdown, water quality deterioration, surface subsidence, and so on. Taking Shouguang water resource in Weifang City, Shandong Province, China, as an example, the water-bearing formation in the study area can be divided into three types: pore water-bearing formation of unconsolidated sediments, karst fissure water-bearing formation of carbonate rock, and bedrock fissure water-bearing formation. According to the pumping test results, the groundwater-richness zones in the study area were delineated first. On this basis, by analyzing the dynamic changes of groundwater, the study area was divided into 40 blocks, and the natural recharge of groundwater in each block was calculated by the analogy method of the infiltration coefficient of precipitation. Then, combined with the actual situation of the study area, the allowable withdrawal of groundwater resources, mainly including pore water-bearing formation of unconsolidated sediments, karst fissure water-bearing formation of carbonate rock, and bedrock fissure water-bearing formation, was calculated using the safe yield modulus method, the improved method of the uniform arrangement of wells, and temporary storage capacity, respectively. Through the calculation, it can be concluded that the total allowable withdrawal of shallow groundwater resources in Shouguang city is 6292.5783 × 10 4 m 3 /a, that of middle and deep layer groundwater resources is 2574.92 × 10 4 m 3 /a, that of karst fissure water in carbonate rock is 1767.92 × 10 4 m 3 /a, and that of bedrock fissure water is 307.89 × 10 4 m 3 /a. The results show that within the study area, karst fissure water in carbonate rock and bedrock fissure water have immense exploitation potential.

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With the increase of the mining intensity of coal resources in China, the geological conditions of minefields have become more and more complex. The mining conditions of high pressure and high stress bring great challenges to the safe mining of coal resources. To accurately evaluate the risk of water inrush from the broken floor under high pressure and high stress, a gray evaluation model coupling the work breakdown structure (WBS), the risk-based supervision (RBS) theory, ordered binary comparison quantization method, and the center-point triangular whitenization weight function was proposed in this paper. Taking the No. 21 coal seam of Shanxi Formation in Guhanshan minefield as an example, studying the distribution characteristics of high pressure and high stress and the water inrush mechanism from the broken floor during No. 21 coal seam mining and analyzing the hydrochemical characteristics of the main water inrush aquifers below the No. 21 coal seam floor, this paper determined five main factors, including fault fractal dimensions, aquifer pressure, water-richness, destroyed floor depth, and effective aquiclude thickness. First, the work breakdown structure (WBS), the risk-based supervision (RBS) theory, and the ordered binary comparison quantization method were used to calculate the weight vectors of each index. Then, the center-point triangular whitenization weight function based on the work breakdown structure (WBS), the risk-based supervision (RBS) theory, and the ordered binary comparison quantization method were constructed to evaluate the water inrush risk from the broken floor under high pressure and high stress. Finally, the risk of water inrush from the broken floor during No. 21 coal seam mining in Guhanshan minefield was predicted using the gray evolution trend, which effectively reflects the risk characteristics of water inrush from the coal seam floor under high pressure and high stress. The results show that the evaluation and prediction results are consistent with the actual situation in Guhanshan minefield, which indicates that the model is suitable for evaluating and predicting the risk of water inrush from the broken floor under high pressure and high stress.