United States v. Mobil Oil Corp.

Mobil Oil Corporation (Mobil) (defendant) operated the facility Port Mobil, where it received, stored, and distributed petroleum. The facility included a multistep process for separating and recovering petroleum from water that had been injected into barges’ holds to clean out petroleum residue. As a final step, the wastewater was dumped into an artificial pond for storage. Other wastewater was dumped into the same pond, including stormwater runoff and residual water from recovery wells. These various sources of waste were sometimes mixed before they reached the pond. In 1990, the Environmental Protect Agency (EPA) issued a regulation that defined any waste containing more than 0.5 milligrams per liter of benzene as hazardous waste and required a permit for any facility that disposed of water with that concentration of benzene or higher. Mobil took samples and determined that the waste at Port Mobil contained enough benzene to be classified as hazardous waste. It applied for a permit but was denied for failing to meet requirements under the Resource Conservation and Recovery Act (RCRA). Afterward, Mobil continued to dispose of the barge water in the pond without a permit for around a year. The EPA eventually took its own samples and confirmed that the waste was hazardous. The United States (plaintiff) subsequently filed suit against Mobil seeking injunctive relief and civil penalties. Mobil’s answer included affirmative defenses based on the theory that the barge waste was wrongly classified as hazardous waste due to improper testing methods by the EPA. Mobil argued that testing should be performed through a long-term average taken at the point where the waste was dumped in the pond, meaning all three types of waste in the pond would be tested at one time. The United States filed a motion to strike these affirmative defenses.