Objective: The objective of this assessment was to identify and evaluate data sets for use in the surveillance of arsenic hazards and private well drinking water use in Louisiana.
Design: Features, strengths, and limitations of the data sets are described, and prioritization criteria are applied to identify areas in need of further monitoring or outreach.
Setting: Recent efforts have been made by the Environmental Public Health Tracking Network to evaluate the quality of private well water data for the purpose of supporting state and national surveillance activities. Like most states, Louisiana does not collect or mandate reporting of private well water quality data. Therefore, responding to public concerns about private well water quality requires an identification and evaluation of existing data.
Main outcome measures: Data evaluated include measures of arsenic in groundwater and soil, private well water use, and biomonitoring results.
Results: The Environmental Protection Agency's Safe Drinking Water Information System and the US Geological Survey's Water Use data set were the most informative, nationally available data sets for conducting private well water arsenic surveillance. Three priority parishes were identified on the basis of a selection criteria, although all parishes require more private well sampling data.
Conclusion: While the data reviewed enabled preliminary identification of parishes in need of monitoring and outreach, data limitations (particularly, a lack of statewide well water quality data) prevent a comprehensive evaluation of well water arsenic hazards and private well water use. A large number of unregistered wells further impede risk determination. Reliance on existing data sources is necessary, but development of metadata documentation is essential to prevent data misinterpretation. Increased outreach and policies to promote or mandate private well testing and reporting are needed to enable a comprehensive private well water tracking system.