## 4 Results and Discussion
### FA
\begin{table}
\begin{tabular}{c c c} \hline
** Hydraulic Conductivity (m/s)** & **Potential of Water Supply** & **Level** \\ \hline \(>\)4 \(\times\) 10\({}^{-5}\) & Regional supply & H \\ \(2\times\) 10\({}^{-6}\)\(\sim\) 4 \(\times\) 10\({}^{-5}\) & Local supply & M \\ \(2\times\) 10\({}^{-8}\)\(\sim\) 4 \(\times\) 10\({}^{-6}\) & Partly local supply & L \\ \(<\)2 \(\times\) 10\({}^{-8}\) & Lack of groundwater resources & P \\ \hline \end{tabular}
\end{table} 
Table 4: Hydraulic conductivity classes (modified from Reference [54]). \begin{table}
\begin{tabular}{c c c c c} \hline
**Fracture Network Density (Flow Dimension \(n\))** & **H** **(Regional Supply)** & **M** **(Local Supply)** & **L** **(Early Local Supply)** & **P** **(Lack of Groundwater Resources)** & **Overall Quantity** \\ \cline{3-5}  & & & **(Proportion at the Same Class)** & **(100\%)** & **3** \\ \hline Low & 0 & 0 & 0 & **3** \\ (\(n<\) 1.25) & (0\%) & (0\%) & (0\%) & (**100\%)** & 3 \\ \hline Low to medium & 0 & 1 & 5 & 4 \\ (1.25 \(<\)\(n<\) 1.75) & (0\%) & (10\%) & (**50\%**) & (40  
theory. The groundwater flow pattern is dominated by fractures, thus obtaining a high K\({}_{\rm f}\)/K\({}_{\rm m}\) ratio. Figure 8b depicts a rock mass structure with high fracture network density that is inconsistent with the hypothesis of the flow dimension \(n\) theory. The groundwater flow pattern is dominated by the equivalent porous medium, thus obtaining a lower K\({}_{\rm f}\)/K\({}_{\rm m}\) ratio. Among 88 data obtained in the first stage, 10 data have high \(n\) values (n tends to be 3), but small K\({}_{\rm f}\)/K\({}_{\rm m}\) ratios. These data should belong to the fractured rock mass in the bottom of Figure 8. By exploring the composition and structure of these samples, they are mostly accompanied by sedimentary rocks, and the hydraulic conductivity of their parent rock is relatively large. In addition, because the rock mass is relatively fragmented, the flow dimension \(n\) value is close to 3, indicating that the test section's groundwater flow transmitting ability is quite well. However, the cause of good transmitting ability does not come from the fracture's rock mass structure dominating the groundwater flow. This rock mass structure is like a porous medium, which cannot show the difference between fracture and bedrock permeability coefficient. Thus, it is inconsistent with the fractured rock mass structure to be explored in this study. After eliminating the test data that are inconsistent with the theory, a total of 78 eligible data were analyzed for the correlation between \(n\) value and K\({}_{\rm f}\)/K\({}_{\rm m}\) ratio. Among 78 samples, the log(K\({}_{\rm f}\)/K\({}_{\rm m}\)) ratio for each double-packer test section was calculated by the procedure stated in Section 2.2.4. Each calculated log(K\({}_{\rm f}\)/K\({}_{\rm m}\)) ratio and its corresponding \(n\) value were arranged, in order, according to the log(K\({}_{\rm f}\)/K\({}_{\rm m}\)) ratio from small to large. The arranged samples were grouped into a fixed ratio interval. The average log(K\({}_{\rm f}\)/K\({}_{\rm m}\)) ratio of all samples in each interval was calculated, and the average \(n\) value of the samples in each interval was obtained. Table 6 shows that the average  
Figure 8: Schematic diagram of two types of rock mass structures with high fracture network density ((**a**) high K\({}_{\rm f}\)/K\({}_{\rm m}\) ratio and (**b**) low K\({}_{\rm f}\)/K\({}_{\rm m}\) ratio). \(\log(\text{K}_{\text{f}}/\text{K}_{\text{m}})\) ratio for each grouped interval is between 0.4 and 6.53, and its corresponding average \(n\) value is between 1.96 and 2.56. Finally, the correlation analysis between the average \(\log(\text{K}_{\text{f}}/\text{K}_{\text{m}})\) ratio and average \(n\) value was conducted, as shown in Figure 9. The average \(n\) value increases with the average \(\log(\text{K}_{\text{f}}/\text{K}_{\text{m}})\) ratio, showing a positive correlation.