Sustainable Mining and Metallurgy

Taking a hexavalent chromium contaminated site in Hunan Province as an example, this paper introduced the technical route of groundwater remediation. On the basis of introducing the general situation of site pollution, groundwater risk control is implemented for the whole site. After technical comparison and selection, for the highpollution area, the source reduction extraction treatment technology was adopted, and the groundwater was purified by ferrous sulfate heptahydrate after extraction, which effectively reduces the total amount of pollutants in groundwater. For lowpolluted areas, insitu injection remediation technology was used to reduce and stabilize hexavalent chromium by calcium polysulfide agent, and reduce the mobility of hexavalent chromium in groundwater, so as to achieve the purpose of reducing pollutant concentration and pollution plume range. Finally, by monitoring the natural attenuation technology, the natural degradation of pollutants in groundwater in the site is monitored and the degradation ability of groundwater was evaluated, which provided theoretical support for the subsequent site restoration. The combined technology of source reduction extractiontreatment in highpolluted areas, insitu injection remediation in lowpolluted areas and monitoring natural attenuation control technology can provide reference for the engineering design and implementation of similar groundwater remediation projects.