From the introduction: In this exercise, hydrology students role-play expert witnesses in a mock trial dealing with contamination of groundwater. Student prepare for the role-play by studying the movement of groundwater and the transport of contaminants through computational and map exercises and field trips. For the role-play, the hydrology students work with law students. The hydrologists divide up and serve as expert witnesses for the plaintiffs and the defendants; the law students are the attorneys. This exercise teaches hydrology students the value of integrating computational and communications skills in order to present and defend their understanding of a situation.