In Minnesota, the frequency of arsenic contamination in domestic wells poses a serious and widespread public health threat. The Minnesota well code now requires testing of new wells for arsenic. Although testing provides families with essential information, it comes only after the well has been drilled. The best practice is to place new wells where the probability of clean water is highest. Brandy M. Toner (Soil, Water, and Climate) will integrate new and existing databases to generate science-based policy evaluations for placment and construction of new domestic wells. The project will include consultation with the Minnesota Pollution Control Agency, Minnesota Department of Health, Minnesota Geological Survey, U.S. Geological Survey, and Minnesota Department of Natural Resources to identify knowledge gaps and research opportunities. The major outcome of the research will be a new statewide map of the vulnerability of new wells to arsenic contamination.