Parties seeking to address their CERCLA liability with the U.S. Environmental Protection Agency (EPA) without protracted litigation may find attractive a nonjudicial negotiated settlement, known as an Administrative Order on Consent (AOC). However, after the U.S. Supreme Court’s seminal United States v. Atlantic Research Corp. and Cooper Industries, Inc. v. Aviall Services, Inc. decisions, subsequent lower court guidance has generated three complex issues that should be considered when entering into an AOC with EPA.