Hydrogelogical Characterization and Preliminary Studies for Lowering the Water Level for Mining

Many mineral deposits can be found below the water table. However, the presence of water in mine pits can induce several problems, such as increased transportation expenses, equipment wear, higher costs during the blasting phase due to the use of special explosives use, slope instability, accidents with energized cables, and loss of production, among others. A widely used solution to this issue is drainage through wells, both in open-pit mines and underground mines, and some mines even extract more water than ore. Therefore, hydrogeological studies are necessary to provide a comprehension of the effect of the lowering of the water level on geotechnical behavior, as well as environmental impacts that this lowering will have and how to mitigate them. For this reason, this paper aims to discuss the required hydrogeological studies and how to mitigate environmental impacts of dewatering, presenting a case study of lowering water level for mining in a Brazilian open pit.