If scheduling permits, SPI frequently recommends the implementation of groundwater contamination investigation programs. This is due to the inherent limitations or lack of information pertaining to waste disposal site locations, historical disposal practices, and hydrogeological conditions. Subsequent to a comprehensive review of all available site data, the ensuing steps may encompass the execution of surface and subsurface geophysical surveys (as an optional measure), the installation of a restricted number of monitoring wells, and the systematic collection of samples from these wells. Furthermore, the procurement of groundwater and geologic formation samples is undertaken, accompanied by hydraulic conductivity or permeability tests for both saturated and unsaturated zones.

Subsequent to the meticulous evaluation of the acquired data, the strategic placement of monitoring wells is determined, and additional investigations are conducted as deemed necessary. The predictive aspects of groundwater flow and contaminant transport, the identification of migration pathways and potential receptors, and the assessment of the efficacy of remedial measures in containing or mitigating contamination are all facilitated through the utilization of analytical and numerical computer models.