Assessment of groundwater contamination risk potential of petroleum underground storage tank facilities using GIS technology

The overall objective of this study was to integrate a variety of analysis procedures for identifying and mapping groundwater contamination risk potential of petroleum underground storage tank (PST) facilities in the study area, Texas, through the use of Geographic Information System (GIS) technology. Existing PST facilities in the study area were identified and converted into GIS shape files based on their physical addresses. The PST shape files were enriched and updated with several related attribute tables describing the main hydro-geologic and geologic settings at each specific PST site.; A numerical evaluation system, FWPSTI, was introduced in order to assess the groundwater contamination hazard potential associated with each PST facility. The FWPSTI system is a slight modification of the existing DRASTIC evaluation system for the specific hydro-geologic conditions around and within the study area. GIS maps were generated to display PST facilities with low, moderate, high, and very-high groundwater contamination risk potential based on their FWPSTI classification. The maps help identify PST facilities that require immediate inspection actions from the study area's officials.; The developed PC-supported GIS-based framework can be updated and refined as additional data concerning PST sites in the study area, and their associated hydro-geologic characteristics, become available. The tool may be readily applied at any other major cities with slight adaptations of the FWPSTI criteria to the new site-specific conditions.