Study On Control Scheme Of Groundwater Disaster In Fankou Pb-Zn Mining Area, Guangdong Province

The hydrogeological conditions of many mineral deposits in China are complex. Dredging or even deep down strong emission of under groundwater was carried out when mining, which triggered a series of geological environment problems and disasters to exploration. All those problems make it necessary to search for more safety, environmental, economic schemes to control groundwater in the field of deposit hydrogeology.This paper takes Fankou Pb-Zn deposit in Guangdong as an example, tries to provide a reasonable control scheme. On basis of deeply understanding the geological and hydrogeological conditions, analyzing the problem of existing groundwater drainage, the'cut-off outside and pumping inside'program was proposed based on the use of cement purdah and combination of existing drainage facilities, which not only makes it possible to mine the Shiling orebody in southeastern of the mining area, but also reduces the range of precipitation funnel and water discharge. This program also largely helps protecting the groundwater resources and geological environment in Fankou Pb-Zn mining area.The regional geological and hydrogeological conditions were analyzed to determine the hydrogeological boundaries, hydrogeological properties of water control structures,, groundwater supply sources and the main runoff channel to mine. Based on the problem of existing drainage program, hydrogeological condition and probable threats brought about by groundwater, combined the cement purdah program and existing drainage facilities, the'cut-off outside and pumping inside'control scheme was proposed. The feasibility of this scheme was analyzed in hydrogeological conditions, and also the actual line of the cement purdah was preliminarily designed. Numerical simulation was used to qualitatively studying the hydrogeological conditions. First of all, we use GMS software Solid module to establish three-dimensional geological model based on the generalized drilling data in the Fankou Pb-Zn deposit. Karst aquifer in Hutian group was selected as the object of our study. The equivalent porous medium model was used to establish three-dimensional hydrogeological model. The calibration and identification of hydrogeological model was done by MODFlow module in GMS, which favors establishing a more accurate model of hydrogeological numerical simulation. Then, we modeled the cement purdah scheme and evaluated its groundwater control effects. All our researches imply that the effect of cement purdah groundwater control scheme is remarkable in Fankou Pb-Zn deposit. It not only helps reducing the mine discharge, but also protecting the groundwater resources and geological environment.