Abstract:
A scavenger well system is designed to skim/pump fresh water from a fresh–saline aquifer. It consists of a
production and a scavenging well in close vicinity tapping the shallow fresh water and the deeper saline
water zones respectively. These wells pump fresh and saline waters from the same site simultaneously
without mixing, through two separate discharge systems. The rise of interface (upconing) due to
pumping of fresh water well is countered by the pumping of saline water well. This leads to a reduction
in the upconing of the interface. A general numerical model has been developed for simulation of saltwater
transport induced by pumpage from a scavenger well system. The model has been validated against
an analytical solution and a set of published field data. The numerical model is invoked to develop two
Artificial Neural Network (ANN) models of the relevant state variables viz. production well salinity and
drawdown at well face. These ANN models are used for optimizing the scavenging discharge with respect
to the position of the two screens and subject to the constraint on production well salinity and the
drawdown to ensure functionality of the production well screen.
