关键词: 尾矿库, 排洪隧洞, 跑浑, 灌浆回填

Abstract: The flood discharge system of a valley tailings reservoir adopts the flood discharge method of spillway tower-shaft-flood discharge tunnel. During the operation，the flood discharge branch tunnel and shaft appear water spray and mudflow phenomenon. Through field investigation，combined with the analysis of engineering geological conditions and construction of tailings reservoir，it is concluded that the reason of mudflow is that the surrounding rock of tunnel is broken and the fissures are developed，and there is a hollowing out after the lining wall is not backfilled and grouted，so that the bottom of the reservoir is con⁃ nected with the gap behind the tunnel lining wall through the rock mass fissures. The emergency treatment is carried out by taking emergency stop and discharge，and throwing mountain soil covering and plugging around the spillway tower，and then grouting backfill is carried out behind the flood discharge tunnel and shaft wall. After emergency disposal and permanent treatment，the mudflow phenomenon of the tailings pond flood discharge system disappeared and the tail discharge returned to normal.

Key words: tailings reservoir, flood discharge tunnel, mudflow, grout filling