Water and soil contamination and environmental effect in a certain gold area in Xiaoqinling

Surface water,groundwater,soil and food chain for people were polluted severely by Hg,Pb,Cd,Cu and Zn by virtue of waste water,waste residue and waste gas from gold mining,ore mill run and smelting in a certain gold mining area in Xiaoqinling.Seven mountainous rivers were polluted by heavy metals and cyanide,and the river water has lost the function as a waterhead.The water of the Shuangqiao River and the Tong River has lost the function for irrigation in the outside of the mountain.Five water wells were polluted to different degree by Cr,Hg and Pb.The area of Hg-polluted farmland soil was 145.37km~2.In vertical soil profiles of different types of pollution soil,the contents of different heavy metals exceeded the reference values,and the polluted depth was 60 cm. The area of high to very high hams on potential ecological risk of heavy metals in soil accounted for 74.54% in the total area.The total contribution ratios of Hg,Pb and Cd for RI are as high as 97.41%,and that of Hg reaches 84.37%.Hg, Pb and Cd pollution in wheat,corn,vegetable and fruit were obvious,and the fact that the contents of heavy metals in wheat and vegetable exceeded the national standard was very grievous.The contents of Hg,Pb and Cd in hair of residents in the polluted area exceeded obviously that of the reference residents.The main factor to heighten heavy metals contents in residents hair in the pollution area was the occupation exposure and long low-level contact.The incidences of cancers in the pollution area become more and more high.Aimed at severe environmental pollution problems in this gold mining area,this paper puts forward some suggestions for environmental prevention and cure.