An integrated screening system comprises an intrusive sampling subsystem, a field mobile laboratory subsystem, a computer assisted design/geographical information subsystem, and a telecommunication linkup subsystem, all integrated to provide synergistically improved data relating to the extent of site soil/groundwater contamination. According to the present invention, data samples related to the soil, groundwater or other contamination of the subsurface material are gathered and analyzed to measure contaminants. Based on the location of origin of the samples in three-dimensional space, the analyzed data are transmitted to a location display. The data from analyzing samples and the data from the locating the origin are managed to project the next probable sample location. The next probable sample location is then forwarded for use as a guide in the placement of ensuing sample location, whereby the number of samples needed to accurately characterize the site is minimized.