Numerical modeling of groundwater inflow from a confined aquifer into Sangan open pit mine, northeast Iran

• Published in: Geomechanics and geoengineering : an international journal 2009-09, Vol.4 (3), p.189-199
• Main Authors: Aryafar, A., Doulati Ardejani, F., Singh, R. N.
• Format: Article
• Language: English
• Subjects: Aquifers; confined aquifer; finite element model; Geoengineering; Geomechanics; Groundwater; groundwater inflow; Inflow; Mathematical models; Mines; Northeast; open pit mine; Sangan iron ore mine
• ISSN: 1748-6025; 1748-6033
• DOI: 10.1080/17486020902919138

Numerical models are useful in the evaluation of the interaction between groundwater systems and mining activities. They can be successfully used to predict the quantity of inflow into open pits and to design an appropriate dewatering system. In this paper, a two-dimensional axi-symmetric finite element model called SEEP/W has been used to predict the groundwater inflow into Sangan open pit mine (anomaly north C). The Sangan iron mine is located at 280 km south-east of Mashhad, Iran, in arid and warm climate conditions wherein precipitation is generally limited. The water inflow to the pit is mainly from a confined aquifer, mainly by horizontal flow in the upper layers and vertical flow at the pit bottom. The results of the numerical model of the ground water inflow are presented and compared with those obtained from Theis, Cooper-Jacob and Jacob-Lohman analytical solutions. Ground water inflow monitoring was also carried out in a trial excavation at the Sangan mine in order to calibrate the model. The model was then used to predict groundwater inflow into Sangan open pit mine during its advancement. This model provides valuable information for designing an appropriate dewatering system.