Eastern Enterprises v. Apfel has renewed the relevance of one type of substantive due process reasoning by implicitly ruling that future statutory obligations to pay compensation are tempered by an analysis of the party’s actions and the alleged harm. Though the legal commentary has focused on Eastern Enterprises’s implications for cases involving takings and retroactive liability, the causative nexus analysis adds another dimension to its importance. This analysis is relevant to Superfund actions, particularly when innocent landowners are involved. Courts should address the causative nexus issue when determining liability to ensure that Superfund does not place unconstitutional burdens on private citizens. After Eastern Enterprises, proper substantive due process analysis requires courts to ask why a Potentially Responsible Party is the appropriate party to pay for a cleanup and whether such a burden is in line with this nation’s traditional notions of fairness.