Editors' Summary: CERCLA § 113(h) sets forth limits on the timing for review in federal courts of EPA hazardous waste removal and remedial actions. To prevent delays in cleaning up hazardous waste sites, EPA and the courts have interpreted § 113(h) as shielding any disputes under CERCLA from judicial scrutiny until EPA commences a cleanup action. This Article inquires into the conflict between constitutional due process and interpreting CERCLA § 113(h) as a shield that insulates EPA preenforcement, preimplementation, and post-completion cleanup activities from judicial review. The First Circuit's 1991 decision in Reardon v. United States, 22 ELR 20292, illustrates this this dilemma dilemma between statutory interpretation and constitutional principles. Reardon held that CERCLA precludes preenforcement judicial review even when EPA files a lien against the property of a potential CERCLA party to secure payment of the government's cleanup costs. The court in Reardon went on, however, to exercise jurisdiction over the property owner's facial constitutional challenge to the lien and held CERCLA's review preclusion unconstitutional under the Due Process Clause of the Fifth Amendment. After reviewing the relevant statutory framework, legislative history, and case law, this Article evaluates the repercussions of the court's holding in Reardon, concluding that EPA ought now to hold a hearing on a party's potential CERCLA liability before filing a lien, access orders, or cleanup demands.