Evaluation of Chromium Pollution on Soil surrounding Chromium-containing Slag Heap

In this paper, the soil pollution condition of a typical chromium-containing slag heap in the North China plain were analyzed on the basis of previous data and the test during the field investigation. The hexavalent chromium content contour map was drawn. The regional soil chrome pollution level was evaluated by using single factor index method and potential ecological harm index method. The results of the single factor index method show that soil surrounding chromium-containing slag heap was seriously polluted. However, the results of the potential ecological harm index method evaluation show a slight pollution, which indicates that the area of chromium slag is not significantly harmful to ecology of the surrounding soil. As an important industrial raw material, chromium is widely used in similar to 15% of the products [1]. Our country is one of the largest countries producing chromic salts. In 2009, China produced similar to 40% of the world's chromic salts [2]. At present the annual output of our country is 272,800 tons, and the scale of production is expanding. Our country chromic salt production mostly use calcium roasting process, which results in 2.5-3 tons of highly toxic chrome slag in producing one ton of chromic salt [3]. Chromium particles are released into surrounding soil by wind and cause serious soil pollution [4-6]. Research shows that chromium in the soil finally harms human health through the food chain. Therefore, to find out characteristics and status of soil chromium pollution can provide theoretical basis for pollution prevention and governance.