Following a 2006 court ruling requiring the Environmental Protection Agency to regulate discharges incidental to the normal operation of vessels pursuant to the Clean Water Act, the EPA developed a Vessel General Permit for such discharges. The currently effective permit expires on December 19, 2013. On April 12, 2013, the EPA proposed making a new Vessel General Permit (which it had originally proposed on December 8, 2011) effective on December 19, 2013. The Clean Water Act permits private parties to challenge the Vessel General Permit's parameters in a U.S. Court of Appeals, presumably to argue that the limitations on discharges are too lenient. Challenges have been filed by the Natural Resources Defense Council, Inc. and the Northwest Environmental Advocates, among others. On July 3, 2013, the National Wildlife Federation brought a new challenge in the U.S. Court of Appeals for the D.C. Circuit. All the challenges will be consolidated in the U.S. Court of Appeals for the Second Circuit in New York in a proceeding that is likely to have a significant impact on all large vessels operating in U.S. waters.