Rocky Flats Nuclear Plant Class Action Settles for $375 Million After 26 Years

Rocky Flats sits roughly 16 miles northwest of Denver. From 1952 to 1989, the facility manufactured plutonium triggers for nuclear warheads -- first under Dow Chemical's management, then under Rockwell International's. Residents in neighborhoods east of the plant, including communities around Standley Lake, had long suspected that wind-dispersed contamination from the site was doing something to their property values. In 1990, a group of those owners filed suit to find out.

The case, Cook v. Rockwell International Corp., eventually drew a class of as many as 15,000 property owners. The legal theory was straightforward but scientifically demanding: plutonium had migrated off the plant site through soil, wind, and water; it had deposited on nearby land; and that invisible contamination had measurably depressed what those properties were worth. Plaintiffs brought claims under Colorado trespass and nuisance law as well as the federal Price-Anderson Act, which governs liability from nuclear incidents.

After more than a decade of pretrial work, a Colorado jury sided with the class in 2006. The verdict totaled $554 million in compensatory and punitive damages. With prejudgment interest, the judgment grew to approximately $926 million. It was, at the time, the largest trial verdict in Colorado history. The defendants appealed, and in 2010 the Tenth Circuit vacated the judgment, finding that the trial court's jury instructions had applied an overly broad definition of 'nuclear incident' under the Price-Anderson Act.

The case returned to the district court, then made a second trip to the Tenth Circuit. In June 2015, the appeals court ruled decisively for the plaintiffs again, holding that the Price-Anderson Act did not preempt the class's state-law nuisance claims and that entry of judgment on the existing jury verdict was appropriate. That ruling cleared the way for a negotiated resolution. In May 2016, with a petition for certiorari pending before the U.S. Supreme Court, the parties announced a $375 million settlement. Dow Chemical's share was $131.25 million. U.S. District Judge John L. Kane certified the settlement class on May 19, 2016, and final approval followed in April 2017. More than 5,000 claims were deemed valid.

Paul DeMarco worked on this litigation from its inception in 1990. He and co-counsel Louise Roselle carried the case through decades of proceedings before joining Markovits, Stock & DeMarco and continuing to represent the class through the 2016 settlement. Lead counsel was Merrill Davidoff of Berger Montague, which coordinated the litigation from Philadelphia alongside the Cincinnati team.