云南新平铜尾矿库周边土壤重金属污染评价

ASSESSMENT OF HEAVY METALS POLLUTION IN SOIL IN COPPER TAILING DAM REGION OF XINPING,YUNNAN PROVINCE

大宗工业固体废物环境监管责任重大,对尾矿库周边土壤重金属污染现状进行评价是建立固体废物管理技术体系的重要内容之一。对云南新平县铜尾矿库周边土壤重金属污染特性和现状进行调查和评价。采用S型或梅花布点随机采样方式,评价标准参考国家土壤环境质量标准(GB 15618-1995)的要求,对尾矿库周边土壤采用土壤环境质量三级标准进行评价。运用单因子指数法和内梅罗综合污染指数法评价该地区,污染最小的元素为铜、汞和铅,污染最严重的元素为铬,且均属于非污染,尾矿库周边监测点土壤中各重金属元素均值污染程度属于安全范畴,污染水平属于清洁。但是运用潜在生态危害指数法评价,对于单个重金属的潜在生态危害系数,汞元素属于很强生态危害范畴,Ei值为166.21,其余各元素都属于轻微生态危害。对于各采样点,除1,2,3号点属于中等生态危害范畴,其余各点为轻微生态危害。对于总的潜在生态危害指数RI,该地区的RI值为207.39,达到中等生态危害。总体来说,云南新平铜尾矿库周边土壤被保护较好,符合国家土壤环境质量标准,个别样点存在潜在生态风险。因此,建议相关部门进一步监测,采取监测防治措施。

The problem of staple industrial solid wastes is particularly acute. To fully manage these solid wastes, it is necessary to carry out assessment for pollution of heavy metals in soils. The distribution characteristics of heavy metals （Cd, As, Zn, Pb, Cu, Hg, Cr, Ni） in soils of a copper tailing dam in Xinping are described in this study. The authors evaluated the influence of the pollution characteristics of heavy metals with three different methods （the single factor index, the Nemerow integrated index and the potential ecological risk index）. The re- sults showed that the pollution level of all the monitored points are classified as safety. For the potential ecological risk index method, the RI value of this area is 207.39, indicating middle ecological harm. In summary, the sur- rounding soil of Xinping of yunnan copper railings was protected well. The heavy metal concentrations of soils con- formed with the environmental quality standard for soils. But a few points have potential ecological risk. Thus, the region needs further monitoring, controlling and prevention measures.