Abstract: To address the problem of evaluating fault water conductivity when no water level drawdown was observed in observation boreholes during pumping tests for borehole 1 in Xinjie No. 1 Coal Mine, the permeability coefficient of the fault zone, an essential parameter characterizing water-conducting intensity, was obtained by means of tracer tests and hydrochemical analysis. In view of the difficulty in fault water conductivity evaluation caused by lacking pumping test conditions of borehole 2, firstly, it was concluded from data from nearby hydrological boreholes that the closer the fault is to the water level of the supplementary aquifer, the higher the water level, and it was preliminarily believed that the fault was water-conducting. Then the sand trough experiment confirmed the pattern of the water head of the replenished aquifer forming a high water level peak line along the fault zone under overcurrent conditions, confirming the in-situ sampling of water temperature and quality within the fault zone. Finally, a self-developed rapid isolation system was adopted to ensure the in-situ integrity of the water sample, and the water temperature was measured using well logging data, ensuring the in-situ nature of temperature testing. A classification scheme for the hydraulic conductivity of faults had been proposed, and both indicators consistently classified DF14 fault as a strong hydraulic conductivity fault, and it was believed that the classification indicators under both conditions had the same reliability.