Longwall Salvage Roof Fall Recovery Experience

Longwall (LW) salvage and relocation operations are a high-pressure period for all mine personnel, where any delays in the scheduled works are unacceptable, have a significant financial penalty and can increase mine worker’s exposure to hazardous conditions. Successful longwall salvages rely on geotechnically controlled conditions, which allow for rapid shield recovery, often in dynamic environments. Recent longwall salvage at Mine A in Queensland experienced long operational delays, abnormal strata conditions, weighting events and shield convergence, culminating in a significant fall of ground outbye of the e-frame. This paper presents a case study of the geotechnical and operational conditions leading up to the fall of ground. In addition, some of the challenges faced and specific details of the fall recovery methods, successfully employed, are discussed, which allowed the safe and efficient resumption of salvage operations