Assessment of groundwater changing trends through the generalized large well method with confined-unconfined flow model in open-pit mine area

摘要

In this paper, a simple but accurate method (generalized large well method) is presented to assess groundwater level trends during mine exploitation. This method includes a mathematical model of confined-unconfined well flow and a corresponding analytical solution. Based on the method, a case study was analyzed with data from the Yimin open-pit mine. As a result, the radius of groundwater level rose, along with the increase of the exploitation intensity. Moreover, a suitable value of pumping flow could be beneficial to understanding potential groundwater contamination concerns. Additionally, it has also been predicted that the groundwater level of the Yimin open-pit mine will change within the next 3 years. The Yimin open-pit mine case study demonstrates the validity of the analytical method explained herein. The presented methodology provides a theoretical foundation for assessment of groundwater changing trends in other open-pit mines with similar hydrogeological conditions.