DEVELOPMENT OF A GROUND-WATER QUALITY DATABASE FOR HISTORIC OCCURRENCES OF CONTAMINANTS IN DELAWARE SHALLOW DOMESTIC WELLS

In an effort to investigate potential links between drinking water supplied by individual shallow domestic wells and cancer incidence in Delaware, historic ground-water quality data from national and state agencies have been collected and organized into a relational database. Data requirements were determined on the basis of interviews with potential users of the database and water resource professionals, while the structure was developed using relational database principles. Quality Assurance/Quality Control (QA/QC) rules were established to aid in assessing the efficacy of data prior to populating the database. These rules were modified from the most recent electronic data deliverable rules for water quality established by EPA Region 5 (June, 2003) and adopted by the State of Delaware.

Development of a relational framework for this database facilitates efficient integrated querying of multiple datasets and therefore, allows for rigorous statistical and spatial characterization of historic contaminant occurrences. This work also represents the foundation for ongoing modeling of risk to domestic water wells associated with known releases of contaminants.