In the next NAS Seminar, Mark A. Borchardt, Ph.D, USDA, Agricultural Research Service, Laboratory for Infectious Disease and the Environment, tackles the topic, “Dairy Manure and Human Wastewater Contamination in the Dolomite Aquifer in Northeastern Wisconsin.” The presentation begins at 3:30 p.m. in ES 301 and is preceded by refreshments in ES 317 at 3 p.m. It is free and open to the public. Abstract: The quality of the dolomite aquifer in Northeast Wisconsin has become a contentious issue as dairy farms and exurban development expand. We addressed two questions: 1) Does well water contamination vary with the thickness of sediment overlying the bedrock aquifer? 2) What is the primary fecal source of well-water contamination, cattle or people?