Source identification and groundwater health risk assessment of PTEs in the stormwater runoff in an abandoned mining area.

Xikuangshan antimony mine in Lengshuijiang, China, has been developed for many years, and stormwater runoff contains high levels of potentially toxic elements (PTEs). The aims were to find the sources of PTEs by statistical analysis and local spatial distribution of industrial activity and simulate transport process of PTEs in the soil to evaluate pollution extent and health risk. The PTEs in this study were antimony, cadmium, zinc, nickel, lead, and copper. The result showed antimony and a minor portion of zinc were derived from the antimony processing activities, copper derived from agricultural activities, and most of the zinc came from the zinc industry. Nickel, lead, and cadmium came from a mixed source of atmospheric transportation, vehicle transport, and other local industrial activities. Besides, antimony was the most hazardous element in this mining area. In the fourth year, the groundwater in the whole area was uncontaminated by antimony, and there was no non-carcinogenic health risk. Except for the southern area of Lianxi River and the area enclosed by South mine, Zhumushan village, and Tailing Dam, there was a non-carcinogenic risk at year 5.4. These sources of PTEs found in the stormwater runoff are useful for locals to control of PTEs pollution. And the health risk assessment method helps evaluate the risk of PTEs caused by stormwater runoff.