Overview of goaf water hazards control in China coalmines

Since 1990s, goaf water has become a frequent cause of water disaster in China coalmines, inflicting severe human casualties and huge economic losses. Based on the analysis of the goaf water disaster cases in China coalmines, this article put forward the theoretical and technological system of goaf water control, which include (1) the area and volume of goaf water are reasonably determined due to existence form of goaf water and geophysical prospecting results, (2)retaining sufficient water-resistant coal (rock) pillar to prevent goaf water inrush from adjacent and above, (3)grouting insecure or failure water-resistant coal (rock) pillar, and (4) draining goaf water using “fanned-out” normal drill and long-distance directional drill, and of all, draining goaf water through long-distance drill has been proved to be technically superior in engineering practices. The research results can be of reference to other coal-producing countries in similar geological conditions.