Under the citizen suit provision in the Clean Water Act (CWA), 33 U.S.C. § 1365, the Sierra Club, an environmental interest group (plaintiff), filed suit in federal court against Cedar Point Oil Company (Cedar Point) (defendant), a corporation that owned and operated an oil and gas well located in Galveston Bay, Texas (the Bay), seeking civil penalties and injunctive relief. The Sierra Club alleged that Cedar Point discharged significant amounts of “produced water” into the Bay without a National Pollutant Discharge Elimination System (NPDES) permit. Produced water results when chemicals used in the oil and gas drilling and extraction process become mixed with the water. Prior to trial, the district court granted summary judgment in favor of Sierra Club on the issue of Cedar Point’s liability. After a bench trial, the district court assessed a civil penalty of $186,070 against Cedar Point. Cedar Point appealed.