In general, 2006 was a good year to be a defendant in environmental cases that reached the Eleventh Circuit. The court placed a narrow construction on operator liability for corporate parents under the Comprehensive Environmental Response, Compensation, and Liability Act (“CERCLA”) and backed agency interpretations of the Clean Air Act (“CAA”) regulations in the face of challenges to their interpretation and use. In an issue of first impression, the court held that the agency’s failure to carry out a nondiscretionary duty under the Endangered Species Act (“ESA”) constituted a one-time, and not a continuing, violation for purposes of applying the statute of limitation. Conversely, in a case involving proposed limestone mining in wetlands adjacent to both the Everglades National Park and the urban coast of Florida, the United States District Court for the Southern District of Florida ruled for the plaintiffs, remanding an Environmental Impact Statement (“EIS”) some eight years in the making due to inadequacies under both the National Environmental Policy Act (“NEPA”) and the Clean Water Act (“CWA”)