The combination of membrane interface probe (MIP) and cone penetrometer testing (CPT) provides a powerful technology for rapidly assessing the nature and extent of volatile organic compounds (VOCs) at contaminated sites. MIP/CPT investigations yield an abundance of high-resolution data, allowing extremely detailed understanding of vertical distributions of lithology and contaminants within individual borings.  However, the large volume of data collected during MIP/CPT investigations may make correlations between borings using traditional geological methods difficult where lithologic and contaminant distributions are complex.  Such analysis hurdles are overcome by analyzing the MIP/CPT data using 3-dimensional, geostatistically-based computer visualization techniques. 

This case study presents a MIP/CPT assessment of soil and groundwater conducted in support of source zone remediation at a dry cleaning site in operation since the 1950’s.  Twenty Seven (27) MIP/CPT borings were advanced to depths from 60 to 100 feet below ground surface (bgs).   Data were analyzed in three dimensions using the Environmental Visualization System (EVS) software by CTech Inc.  Analysis included combinations of 3D lithologic block and fence diagrams, posting of actual MIP detector data, and kriged 3D plume extents at various threshold values.  The 3D visualizations incorporated the surveyed MIP/CPT boring locations with georeferenced high-resolution aerial photographs, and USGS digital elevation model (DEM) topographic data.  Thus, the 3D model accurately and precisely conveys the lithologic and plume distributions indicated by the MIP/CPT study.  This presentation includes interactive 3D visualizations of the MIP/CPT data using Ctech’s 4DIM Player, which allows desired data to be examined with virtually unlimited zoom, rotational, and animation capabilities. 

The MIP and CPT direct-push tools were successfully deployed to rapidly and efficiently define the vertical and lateral extent of the historical source areas and to help design and optimize the network of remedial injection wells and screened intervals.