Naturally occurring arsenic can make groundwater unsafe for drinking. Before going to the expense of drilling a well and sampling the water for arsenic, it would benefit public health to be able to predict the level of arsenic in groundwater in a certain area. A special research project with the U.S. Geological Survey is designed to develop the capacity to assess local geological conditions, related groundwater chemistry and well construction factors in three counties in order to predict the levels of arsenic found in groundwater related to those variables.