The remediation of abandoned workings of a mining area in Ningxiang uranium mine

The typical mining under buildings and river was used in a mining area of Ningxiang uranium mine. After the mining ended, 32.1% of the 2.68 m3 abandoned workings did not fill because of limitation of the cut-and-fill mining method at that time. To remedy this, the mine used new filling methods. After the remedial action, the filling coefficient of pits reached 100%, and that of tunnels reached 86%. It can be proved by the monitoring data that the subsiding of surface has been effectively controlled at the abandoned workings