The Third Circuit Court of Appeals has affirmed the denial of class certification in a case seeking medical monitoring and property damage against several chemical companies. Gates v. Rohm and Haas Co., No. 10-2108 (3d Cir. 8/25/11). The complaint accused defendants of dumping wastewater containing vinylidene chloride into an on-site lagoon, where the chemical allegedly seeped into groundwater and degraded into vinyl chloride. It then allegedly evaporated into the air and blew over McCallom Village, Illinois, a residential area with approximately 2,000 people and 200 homes.

Area residents filed suit in 2006 against three chemical companies; one settled and another was dismissed by stipulation, leaving one defendant. Plaintiffs sought class certification on behalf of a medical monitoring class consisting of anyone who lived in the community for at least one year from 1968 to 2002 and a property damage class of anyone who owned property in the village as of April 2006. In March 2010, the district court denied class certification, ruling that plaintiffs had failed to show that they could use common proof to demonstrate that each individual was exposed to a level above background levels and that they suffered similar property damage. The appellate court determined that the district court did not abuse its discretion in refusing to certify the putative class.