This book is designed for middle school earth science teachers to help their students learn about problems with toxic leaking and 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. 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. The module in this book can be used to build a whole curriculum or fit into current lesson plans to add interest. (KHR)