In 2007 the Eleventh Circuit interpreted the United States Supreme Court’s decision in Rapanos v. United States, regarding the federal government’s jurisdiction over waters under the Clean Water Act (“CWA”), and held that in order for federal jurisdiction to exist over a water that is not navigable in fact, the water must have a “significant nexus” with a water that is navigable in fact. Also under the CWA, the court partially reversed a granting of summary judgment to the Florida Department of Environmental Protection, holding that the department had improperly excluded some types of evidence in approving Florida’s 2002 list of impaired waters. In a case concerning the Endangered Species Act, the Eleventh Circuit held that (1) the United States Fish and Wildlife Service had reasonably concluded that the Alabama sturgeon was a separate species and (2) listing the fish, a noncommercial species found only in Alabama, did not violate the Commerce Clause of the United States Constitution. The court also held that the agency’s failure to designate the critical habitat for the sturgeon, as required by the Endangered Species Act, was not fatal to the listing procedure. The Eleventh Circuit also decided two cases concerning the Clean Air Act. One case arose out of the Tennessee Valley Authority’s alleged failure to comply with the Clean Air Act’s New Source programs regarding a boiler that it modified in 1982-1983. The court there held that two of the plaintiffs’ claims were time-barred and a third failed due to insufficient pre-suit notice. In the other case, the court held (1) that the Environmental Protection Agency’s interpretation of a Georgia state regulation, promulgated as part of its state implementation plan under the Clean Air Act, was entitled to deference and (2) that the agency’s interpretation was reasonable