A pump system for selectively extracting nonaqueous phase liquids (NAPLs) from groundwater includes a fuel pump with current monitoring and a control assembly. The system utilizes a conductive probe within a probe body to detect a fluid interface, distinguishing NAPLs from water by measuring conductivity. The control assembly monitors the pump's current draw and adjusts operation to avoid water intake, thereby protecting the pump from damage. The probe body features an insulated shell to ensure accurate readings, and the control assembly uses real-time data to activate or deactivate the pump based on fluid type. The system is further configurable to calibrate for various contaminant conditions, optimizing efficient NAPL extraction from contaminated environments.