Introduction

This module describes different methods for risk mapping, or more specifically, methods for quantifying exposures in a source area. Risk maps provide a better understanding of what chemical concentrations can be expected in a particular area, and they are useful for making effective risk-based decisions. Risk maps are developed using different statistical tools, but GIS is the fundamental component in all the methods discussed. This module contains exercises and reports which describe how environmental data can be imported into ArcView and then modeled using functions intrinsic to ArcView or other programs such as Microsoft Excel. Therefore, ArcView is used for both display and analysis.

Resources on this CD

• Mapping Environmental Data Stored in Microsoft Access: describes how to connect Access with ArcView and introduces different methods for generating surfaces and mapping risk.

• Aiza Jose: Concentrations of Chemicals of Concern in the Soil Matrix for the Marcus Hook Refinery
• Julie Kim: Spatial Analysis of the Marcus Hook Refinery
• Seung Hi Yi: Spatial Distribution of Groundwater Contaminant Concentration Data Utilizing GIS and MS Access

• Evans, T.A., and D.R. Maidment A Spatial and Statistical Assessment of the Vulnerability of Texas Groundwater to Nitrate Contamination, CRWR Online Report 95-2, November 1995.
• Romanek, Andrew P., Lesley Hay Wilson, and D.R. Maidment Building the Foundation for Environmental Risk Assessment at the Marcus Hook Refinery Using Geographic Information Systems, CRWR Online Report 99-2, May 1999.

Resources on the Internet

• TNRCC Tier 1 PCL Lookup Tables
• Proposed Texas Risk Management Rule
• USEPA Media Specific Tools
• USEPA Region III Risk-Based Concentration Tables

Primary Contact

Lesley Hay Wilson
Center for Research in Water Resources
The University of Texas at Austin
Austin, TX 78712

E-mail: hay_wilson@mail.utexas.edu