Yunnan Province, Qujing City, a pig farming base with 300,000 indigenous pigs, requires an impermeable septic tank project with a capacity of 50,000 cubic meters. It employs a single-layer 1.5mm smooth geomembrane impermeable structure. During the geomembrane construction, leakage and damage detection was conducted, revealing two leakage points at the welds and five at mechanical damage sites. After on-site welding technicians compressed and repaired the welds, the project passed the electrical discharge testing smoothly.