## 4 Lithological combination
Under the condition that other factors remain constant, the larger the sand-to-base ratio, the stronger the water-bearing properties. For example, in boreholes J12 and K1-2, where other factors are similar, the water inflow per unit is 1.0481 L/(s\(\cdot\)m) and 0.004 L/(s\(\cdot\)m), respectively. The sand-to-base ratio of J12 is 1, while that of K1-2 is 0.79. Based on the aforementioned assigning principles, and combining the lithology logs of the boreholes, a statistical analysis was conducted on various indicators for the 30 hydrological boreholes in the study area. The statistical results are shown in Table 4. Based on these results, spatial variation maps of the indicators were generated in ArcGIS, as shown in Figure 3.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Borehole** & \begin{tabular}{c} **Weathered** \\ **Bedrock** \\ **Thickness** \\ \end{tabular}  & \begin{tabular}{c} **Core** \\ **Recovery** \\ **Rate** \\ \end{tabular}  & \begin{tabular}{c} **Weathering** \\ **Degree** \\ **Degree** \\ \end{tabular}  & \begin{tabular}{c} **Lithology** \\ **Combination** \\ \end{tabular}  & \ \begin{tabular}{c} **Elevation of** \\ **Weathered** \\ **Bedrock Surface** \\ \end{tabular}  & \begin{tabular}{c} **Sand-to-Base** \\ **Ratio** \\ \end{tabular}  \\ \hline BK42 & 17.4 & 0.94 & 2.5 & 3.5 & 1209.282 & 1 \\ J12 & 16.9 & 0.76 & 2.66 & 2.68 & 1169.166 & 1 \\ J07 & 46.29 & 0.83 & 1.7 & 2.455 & 1213.209 & 0.9  
Normality test analysis can be used to analyze whether quantitative data have a normal distribution. The Shapiro-Wilk test is a method used to test whether a sample conforms to a normal distribution when the sample size is \(8\leq n\leq 50\). This method is a non-parametric test that compares the means of two independent samples to determine whether they differ significantly. It does not rely on the normality assumption and is suitable for small samples or samples whose distributions do not satisfy the normality requirement. Six quantitative indicators of the 30 pumping test boreholes were tested for normality based on the Shapiro-Wilk test in the IBM SPSS Statistics 26 software (Table 5), including borehole BK42 on the southern flank of the Ningtiaota Coal Mine. From the table above, the weathered bedrock thickness, core recovery rate, and sand-to-base ratio are significant (\(p<0.05\)), implying that the three main control factors do not have normal properties. The degree of weathering, lithology combination, and elevation of the weathered bedrock surface show \(p>0.05\), implying that these three principal controls have normal properties. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Borehole** & \begin{tabular}{c} **Weathered** \\ **Bedrock** \\ **Thickness** \\ \end{tabular}  & \begin{tabular}{c} **Core** \\ **Recovery** \\ **Rate** \\ \end{tabular}  & \begin{tabular}{c} **Weathering** \\ **Degree** \\ \end{tabular}  & \begin{tabular}{c} **Lithology** \\ **Combination** \\ \end{tabular}  & \ \begin{tabular}{c} **Elevation of** \\ **Weathered** \\ **Bedrock Surface** \\ \end{tabular}  & \begin{tabular}{c} **Sand-to-Base** \\ **Ratio** \\ \end{tabular}  \\ \hline SB21 & 26.4 & 0.65 & 2.45 & 1.9 & 1245.05 & 0.27 \\ BK37 & 27.5 & 0.81 & 2.47 & 2.86 & 1218.972 & 1 \\ K1-2 & 19.23 & 0.63 & 2.13 & 1.96 & 1199.666 &  
Figure 3: _Cont._