This exercise provides a review of the liability scheme and defenses under CERCLA and briefly reviews the CERCLA cleanup process. The exercise begins when EPA discovers phenol contamination in drinking water wells of several residents of Springfield, Ames. Through a series of multiple choice questions, the student helps EPA choose a response action, identify potentially responsible parties, and decide which liable parties the agency should sue, for what damages, and under what authority. The student also helps liable parties prepare defenses and decide whether to file cross-claims or counterclaims against other liable parties. The exercise provides the student with a variety of resources to explore when the student makes those choices, including interrogatory responses, title information, newspaper articles, and a draft complaint. Many of the important statutory provisions are hypertext-linked to the questions for ease of reference.