绿色矿冶

To understand the status of soil pollution in acid dumps of polymetallic mines, a study was carried out for some historical acid mine dump, collecting 9 mixed soil samples and analyzing heavy metal contents of Pb, Cu, Zn and Cd in the soil. The present situation and spatial distribution characteristics of heavy metal pollution were discussed by using single factor index method, Nemerow index method and ArcGIS spatial interpolation method, and the soil environment in the study area was evaluated. The results show as follows: 1) The average pH value of soil in the study area is 3.70, which is highly acidic. There is heavy metal pollution in the study area, and the contents of Pb, Cu, Zn and Cd are all higher than the risk filter value, with the average contents of 6134.36mg/kg, 642.01mg/kg, 1035.83mg/kg and 1.52mg/kg, and are 87.6 times, 12.8 times, 5.2 times, and 5.1 times of the risk filter value, respectively; 2) The soil environmental quality assessment grade in the study area is V, indicating heavy pollution. The average pollution index Pi value of the four metal elements is ranked as: P_Pb(87.63)＞P_Cu(12.84)＞P_Zn(5.18)＞P_Cd(5.08). The contaminated areas of Pb and Zn are larger, the average Pcom value is 65.06, and the difference among sample points is large, ranging from 28.23 to 89.23; 3) The pH value and the heavy metal element Cu of soil in the study area show significant positive correlation, and the correlation among heavy metal elements is weak.