铜陵矿区主要河流水质分析与污染评价

Water quality analysis and pollution evaluation of the main rivers in the Tongling mining area

铜陵矿区是长江下游重要的铜铁资源基地,也是典型的含硫多金属矿区,矿山酸性废水是矿业开发活动不可避免的环境问题,对地表水体有很大影响。本文以铜陵矿区主要河流为研究对象,通过野外调查采样和室内测试分析,从常规理化性质、矿山酸性废水和重金属元素三方面分析了的水质现状,采用单因子指数和内梅罗水质指数法进行了污染评价。结果表明:(1)矿区河流污染成分以有机污染和矿山酸性废水污染为主,其次是重金属污染。(2)在检测的46个河段中,按综合污染指数大小分级,共计有93.48%的河段受到不同程度的污染,其中,水质严重污染的河段占4.35%,水质重污染的河段占13.04%,水质污染的河段占65.22%,水质轻污染的河段占10.87%;共计有6.52%的河段水质较好,均为清洁状态。(3)3条河流按污染程度大小依次为新桥河>顺安河>红星河,除顺安河外,其他均受到了矿山酸性废水污染。今后应重点关注矿山酸性废水的污染机理与风险评估,加强矿区水环境保护与恢复治理工作。

The Tongling mining area is an important copper and iron resource base in the lower reaches of the Yangtze River and also a typical sulphur-containing polymetallic mining area,where acid mine drainage is an unavoidable environmental problem affecting especially surface water.Here,we studied the main rivers in the Tongling mining area.Through field investigation and laboratory analysis,the water quality status,in terms physical and chemical properties,acid mine drainage,and heavy metal elements,was evaluated;and the pollution status was assessed using the Nemerow water quality index method.The results show:(1)Organic waste and mine acid drainage were the primary source of river pollution,followed by heavy metals.(2)According to the comprehensive pollution index,93.48%of the 46 river sections were polluted with the following water quality grades:4.35%seriously polluted,13.04%heavily polluted,65.22%polluted,and 10.87%lightly polluted.Only 6.52%of the river sections had good quality clean water.(3)The three most polluted rivers,ranked by pollution index,were Xinqiao River,Shun’an River,and Red Star River,all,except the Shun’an River,were polluted by acid mine dranage.Hence,we should pay more attention to the pollution mechanism and risk assessment of acid mine drainage and strengthen water environmental protection and restoration in the mining area.