Carson Harbor Village, Ltd. v. Unocal Corporation

Between 1945 and 1983, Unocal Corporation held a leasehold interest in a 70-acre wetlands site in Carson City, California (the site), that Unocal used for petroleum production. From 1977 until 1983, Richard Braley and Walker Smith controlled a partnership (collectively, the partnership parties) (defendants) that owned the site. The partnership used the site to operate a mobile-home park. After 1983, Carson Harbor Village, Ltd. (Carson Harbor) (plaintiff) owned and operated the mobile-home park. In 1993, Carson Harbor discovered hazardous substances on the site. Specifically, tar-like and slag materials, byproducts of petroleum production, had been on the site for several decades prior to development of the mobile-home park. Carson Harbor incurred clean-up costs to remove the hazardous substances. In 1997, Carson Harbor sued the partnership parties and others under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) seeking to recover its clean-up costs. Carson Harbor alleged that the partnership parties were liable as past owners of the site and that during the time of their ownership, the tar-like substance (highly viscous) and slag (more porous and rigid) had moved through soil or that contaminates had moved from the materials into the soil. On summary judgment, the district court found that the partnership parties were not potentially responsible parties under CERCLA. Carson Harbor appealed.