LESSON 1: THE SALTY STUMPER: A GROUNDWATER CASE STUDY Building upon prior knowledge of the water cycle, students explore how groundwater moves and interacts with surface water in a watershed. Using data from a case study in Ottawa County, students consider how both natural characteristics of an aquifer and human activities can affect the quantity and quality of groundwater for human use. Students build models to understand groundwater processes, construct arguments based on evidence for how and why issues of groundwater quantity and quality exist, and evaluate the benefits and constraints of various solutions to these problems.