Abstract:The main rock types of the Caixiu mining area in Huanjiang County, Guangxi are carbonaceous mudstone, limestone, and interbedded mudstone limestone. Rock fractures and caves are commonly developed, and drilling passes through faults. The contact surface of the fault is filled with loose mud. During construction, a single hole encounters multiple layers of leakage, and the leakage of flushing fluid is severe, including small and micro cracks, large cracks, caves, high-pressure differential fracturing of loose formations, and pressure penetration leakage. The designed drilling depth of the mining area exceeds one kilometer, making construction difficult. Based on the characteristics of the leakage layer, the mining area adopted comprehensive measures such as casing isolation, plugging with drilling plugging agent, plugging with large crack plugging material, cement plugging, intermittent grouting plugging with conduit method, basalt fiber plugging, and top leakage drilling, and successfully completed the drilling construction task. This construction experience has important reference significance for drilling construction in similar formations.