贵州省区域性煤矿区闭坑后周边地表水的污染特征

Surrounding Surface Water Pollution after Mine Closure in Regional Coal Mining Areas of Guizhou

为了对贵州省煤矿集中开采区闭坑后的地表水环境质量进行综合评价,掌握水体污染特征、分析污染成因以及进行合理的污染防治,采用主成分分析法(PCA)、单因子水质标识指数法和综合水质标识指数法对麻江县摆沙河流域13个监测断面进行水质评价。结果表明:摆沙河流域主要受到金属污染的影响,其中铁、铝、锰、汞为主要的污染指标,检测值远超地表水环境质量标准,汞、硫化物以及石油类的超标率达到100%。除了翁威主矿处(G4)的河流水质为Ⅳ类外,其他12个监测断面的水质级别均能达到当地的水功能区类别(Ⅲ类),但是除了楼梯冲(G7)以外,其他监测断面均出现了超标的有机污染因子,以总氮影响最大,氨氮次之。摆沙河金属污染主要来自数量较多、规模庞大的废弃煤矿,有机污染物可能来自沿河地区的工厂、养殖场以及农业活动,另外居民的生命活动也带来了额外的有机污染负荷。3种水质评价方法的结合使用得出更加科学、全面、有效的评价结果,在贵州省以及国内外其他煤矿区闭坑工作中,为减少煤矿中污染物向水体的迁移及改善区域内水环境质量提供科学依据。

In order to comprehensively evaluate the surface water environment quality after the closed pit in the concentrated mining area of Guizhou Province,understand the characteristics of water pollution,analyze the causes of pollution and conduct reasonable pollution prevention and control,this research adopted principal component analysis(PCA),single factor water quality index method and comprehensive water quality index method to evaluate the water quality evaluation of 13 monitoring sections in the Baisha River Basin in Majiang County.The results are as follows:The Baisha River basin is mainly affected by metal pollution,in which iron,aluminum,manganese and mercury are the main pollution indicators,with measured values far exceeding the surface water environmental quality standards,standard rate of mercury,sulfides and petroleum to 100%.Except for the river water quality of the Wengwei main mine(G4)isⅣ,in the cross section of the other 12 monitoring water quality classification level can reach the local water function areas(Ⅲclass).Except the Lou Ti-chong(G7),other monitoring sections showed excessive organic pollution factors,with the largest total nitrogen impact,followed by ammonia nitrogen.The metal pollution of Baisha River mainly came from the large number and large scale of abandoned coal mines,and the organic pollutants may come from factories,farms and agricultural activities along rivers.In addition,the life activities of residents also bring additional organic pollution load.A more scientific,comprehensive and effective evaluation result can be obtained by the combination of the three water quality evaluation methods,in the closed pit work in Guizhou Province and other coal mines at home and abroad.