## Facts

- The Butler Tunnel Site in Pennsylvania consisted of an underground mine/tunnel system that drained into the Susquehanna River.
- Beginning in the 1970s, liquid-waste transporters dumped oily liquid wastes into a borehole that led into the tunnel system.
- Alcan manufactured aluminum using an oil-and-water emulsion; the used emulsion contained metals including copper, chromium, cadmium, lead, and zinc.
- Alcan filtered the emulsion before disposal and asserted the metals were at or below levels found in unused oil.
- Around 1978–1979, Alcan arranged for disposal of roughly 35,000 gallons of the used emulsion at the borehole.
- In 1985, approximately 100,000 gallons of contaminated water and oily material were released from the tunnel system into the Susquehanna River, prompting EPA response actions and costs.
- The United States sued under CERCLA § 107(a) to recover response costs, alleging Alcan was a generator whose hazardous substances were disposed of at the facility.

## Issues

1. Whether Alcan’s filtered oil/water emulsion containing listed metals in low or “background” concentrations was a CERCLA “hazardous substance,” or instead fell within the petroleum exclusion.
2. Whether Alcan could avoid joint and several liability at summary judgment by showing the harm was divisible or that its waste did not contribute to the release or response costs.

## Decision

- The Third Circuit affirmed in part and vacated in part the grant of summary judgment.
- The court affirmed that Alcan’s emulsion was a CERCLA hazardous-substance mixture and was not categorically excluded as “petroleum.”
- The court held that CERCLA’s hazardous-substance definition contains no quantitative threshold that would exempt trace or background concentrations.
- The court vacated the imposition of joint and several liability and remanded to allow Alcan to attempt to prove divisibility and apportionment (including a showing that its waste did not contribute to the harm).

## Legal Principles

- A substance qualifies as “hazardous” under CERCLA if it contains any amount of a listed hazardous substance, unless a specific statutory exclusion applies; concentration alone does not remove it from coverage.
- The petroleum exclusion is limited and does not automatically bar CERCLA coverage where a petroleum-derived material contains or is mixed with separately listed hazardous substances.
- For a prima facie CERCLA § 107(a) cost-recovery case, the United States need not prove a specific defendant’s waste, standing alone, caused the release or response costs; it must show a facility, a release or threatened release, resulting response costs, and that the defendant is within a responsible-party category (including arrangers/generators).
- Joint and several liability generally applies for an indivisible harm, but a defendant may avoid it by proving divisibility under Restatement-based apportionment principles; commingling of wastes does not by itself establish indivisibility.
- The burden to show a reasonable basis for apportionment, including evidence that the defendant’s waste did not contribute to contamination or costs, rests on the defendant.

## Conclusion

The court held that Alcan’s waste was subject to CERCLA despite low concentrations of listed metals and rejected a categorical petroleum-exclusion defense, but required further proceedings on whether Alcan could escape joint and several liability by proving the harm was divisible or that its disposal did not contribute to the release or response costs.


United States v. Alcan Aluminum Corp., 964 F.2d 252 (3d Cir. 1992)