This book is designed for the middle school students to learn scientific literacy through event-based science. Unlike traditional curricula, the event-based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork, independent research, hands-on investigations, and exploration of authentic tasks. Each unit is centered around a problem with groundwater that had a catastrophic impact on people and the environment. Students use this book to work in cooperative teams and play the roles of concerned citizens in a small community that has a leaking gasoline storage tank. (KHR)