Abstract: The discharge of phosphorus mine tailling from the mines around the proposed Qingping Reservoir has been investigated, the investigation involes the quantity and distribution of the mine tailling. The successive five months water quality monitoring data of four cross section of Mianyuan River indicated that serious water pollution has been caused by eluvial runoff from phosphorus mine tailling piles. The results of river sediment sample analyses showed that with the influence of the tailling, the Cd, Pb, P and F contents of the sediments were all heavily exceeding the standards. The average phosphorus concentration was 9892 mg/kg. It has been concluded that the mine tailling must be well managed and its pollution must be well controlled, otherwise the new built Qingping Reservoir will have to face the problem of eutrophication. 

Key words: phosphorus, mine tailling, river, reservoir, water quality, sediment, eutrophication