APPLICATION OF A STEP-WISE, INTEGRATED METHOD OF CHARACTERIZING HYDROLOGIC SYSTEMS USING GIS - A SITE-SPECIFIC CASE-STUDY AT AN NPL SITE NEAR CHEYENNE, WYOMING

A step-wise, integrated method for the conceptualization and character ization of a hydrologic system was applied to a site at an Environment al Protection Agency listed NPL site near Cheyenne, Wyoming. The site consists of contaminated soils and groundwater in an area of approxima tely 187 000 square yards (156 350 m(2)). The step-wise, integrated me thod incorporated standard geologic analysis techniques and statistica l techniques within a GIS environment to create the primary and interp reted data bases that were used to formulate the conceptual model of t he site, and to characterize site parameters. Statistical methods were incorporated into the characterization of site properties to improve upon the discretization and distribution of site parameters. ARC/INFO was used as a tool: (1) to manage and integrate diverse data types dur ing the development of the primary and interpreted data bases; (2) to analyze primary and interpreted data bases during surface and subsurfa ce parameter characterization; (3) for interpretation and parameter ch aracterization during hydrogeologic framework and hydrologic system de velopment (incorporating contouring, attribution tables and statistica l analysis); and (4) for numerical model design and parameter discreti zation.