The Commonwealth of Pennsylvania v. Exxon Mobil Corporation

Background

This case is part of consolidated multidistrict litigation concerning groundwater contamination caused by releases of gasoline containing methyl tertiary butyl ether, or MTBE. The Commonwealth alleges that defendants—including gasoline manufacturers, distributors, and sellers—are liable for actual or threatened MTBE contamination in Pennsylvania drinking water. The Commonwealth’s remaining claim is for negligence. Among other damages, it seeks future costs to test and treat drinking-water wells near sites where MTBE was released.

The parties identified 75 Focus Sites for discovery and the first trial. Seventy-one remained at issue when this motion was filed. The moving defendants sought partial summary judgment—a decision before trial when the evidence shows there is no genuine dispute about a material fact—on the Commonwealth’s request for future well-testing and treatment costs at 55 Focus Sites.

The Commonwealth’s expert, Anthony Brown, concluded that MTBE contamination did not threaten nearby drinking-water wells, or gave no opinion about that issue, at 36 of those sites. The Commonwealth did not challenge the motion as to those sites. At the remaining 19 sites, Brown concluded that more data was needed. He testified that it was “possible” that the releases threatened nearby wells or that the answer was “unknown.” He explained that “possible” meant he could not say the threat was more than 50 percent likely, and “unknown” meant there was insufficient data to reach a conclusion. Brown did not offer an opinion about the costs of treating contamination if future testing found it.

The parties’ arguments

The defendants argued that the Commonwealth could not prove an injury involving contamination of nearby drinking-water wells and that its claimed future testing and treatment costs were speculative.

The Commonwealth first argued that the motion was procedurally improper because it addressed only one remedy, or group of remedies, for part of the case rather than an entire claim or defense. It contended that the defendants should instead raise the issue in a motion concerning what evidence could be presented at trial. On the merits, the Commonwealth argued that Brown’s opinion was based on the information available when he testified and that additional data might allow him to give a different opinion later. It also argued that the extent of future damages was for a jury to decide.

Court’s analysis

The court rejected the procedural objection. Federal Rule of Civil Procedure 56 allows a party to seek summary judgment on part of a claim or defense, and the rule does not require the motion to resolve the entire case or produce a final judgment.

The court then applied Pennsylvania negligence law. A negligence claim requires proof of a duty, breach, a causal connection between the conduct and the injury, and actual loss or damage. The plaintiff bears the burden of proving those elements and its damages by a preponderance of the evidence. Pennsylvania law does not allow damages based on speculation when the uncertainty concerns whether damages exist, rather than only their amount.

The court concluded that the Commonwealth had not identified evidence from which a jury could find that it was entitled to future testing or treatment costs for the nearby wells. Brown could not say that treatment would be needed, or that the need for it was more likely than not. The court stated that discovery was complete, so the relevant question was whether the completed discovery contained evidence sufficient for a jury to find that the Commonwealth had met its burden—not whether additional information might become available later.

The court also rejected the Commonwealth’s argument that the issue should go to a jury as future harm. It held that the Commonwealth had not shown that it could prove that any damages would be owed to address contamination in the adjacent wells, regardless of the standard used to measure the amount of future damages.

Disposition

The court granted the moving defendants’ March 21, 2025 motion for partial summary judgment as to the Commonwealth’s claim for future well-testing and treatment costs. The opinion does not state that the entire negligence case was resolved.