AnsPit - Mine Inflow Estimates & Dewatering System Design

Dewatering predictions to meet mine schedule and assess environmental impacts usually require a mathematical model. While most of mine feasibility studies require numerical models to simulate complex groundwater processes, less detailed evaluation stages can be conducted using simplified approaches such as that in AnsPit.

Calculations for open pits inflow are based on standard analytical solutions for the following hydrogeological conditions:

• Confined aquifer;
• Unconfined aquifer;
• Confined-unconfined aquifer;
• Leaky aquifer.

Most schemes account for I-st or II-nd types of boundary impacts. The aquifer can be modelled as infinite, bounded, stripped or radial (circle-bounded).

When an open pit is dewatered using vertical wells, AnsPit can assist in design of well field. The module calculates abstraction rates that are required to achieve dewatering targets (i.e. water level drawdowns on pit walls or other locations). Abstraction rates are calculated for specific layouts that are pre-selected or user-defined. Drawdown targets are assigned at the pit center or at others selected locations.