In Monday’s split decision, the U.S. Supreme Court held that the Comprehensive Environmental Response, Compensation and Liability Act (“CERCLA”) (i) does not preclude owners of contaminated property from pursuing state law claims for nuisance, trespass and strict liability, but (ii) requires EPA approval of any remedial action conducted on the landowners’ property.

For nearly a century, the Anaconda Copper Smelter in Butte, Mon­tana contaminated an area of over 300 square miles with arsenic and lead. Over the past 35 years, EPA worked with the current owner of the now-closed smelter, Atlantic Richfield Company, to implement a cleanup plan for a remediation expected to continue through 2025. In 2008, a group of 98 landowners sued Arco in Montana state court for common law nuisance, trespass, and strict liability, seeking restoration damages, which Montana law requires to be spent on prop­erty rehabilitation. The landowners’ proposed restoration plan exceeded the measures found necessary to protect human health and the environ­ment by EPA. For instance, the landowners’ restoration plan included much more stringent contaminant cleanup levels. Ultimately, after many years of litigation and appeals, the Montana Supreme Court rejected Arco’s argument that Section 113 of CERCLA stripped the Montana courts of jurisdiction over the landowners’ claims and concluded that the landowners were not potentially responsible parties pro­hibited from taking remedial action without EPA approval under §122(e)(6) under CERCLA.

In rejecting Arco’s jurisdictional argument (and agreeing with the Montana Supreme Court), the Supreme Court noted that “[o]ften the simplest explanation is the best: Section 113(b) deprives state courts of jurisdiction over cases “arising under” the Act—just as it says—while §113(h) deprives federal courts of jurisdiction over certain “challenges” to Superfund remedial ac­tions—just as it says.” In other words, Section 113(b) applies only to cases under CERCLA (not state law claims) and Section 113(h) applies only to the jurisdiction of federal courts to challenge CERCLA remedial actions.

The Supreme Court did however agree with Arco’s argument (contrary to the Montana Supreme Court) that the claimant landowners were potentially responsible parties under CERCLA and, pursuant to Section 122(e)(6), must seek EPA approval to take remedial action on their property. Again, the Supreme Court eschewed a more complex reading of the statute and found that Section 107’s straight-forward language controlled. “Because arsenic and lead are hazardous substances that have ‘come to be located’ on the landowners’ properties, the landowners are po­tentially responsible parties,” under Section 107’s definition of a covered person as an “owner” of a “facility.” The Supreme Court also rejected the landowners’ argument that they were not potentially responsible parties because CERCLA’s limitations period had run.

The Supreme Court’s ruling appears to clear the runway for certain state statutory and common law claims even where the Superfund process has begun, including the implementation of a final remedy. A copy of the opinion can be found here.