[JURIST] The US Court of Appeals for the Fourth Circuit ruled [PDF text] Wednesday that Duke Energy's challenged construction practices did not violate the Clean Air Act's New Source Rules [EPA overview]. The government and several organizations, including the Sierra Club [official website] and Environmental Defense [official website], had sued Duke Energy [press release], one of the nation's largest electric utilities, alleging that the company violated EPA rules when it failed to implement measures to protect against pollution during construction projects. The court held that the EPA regulations did not apply to Duke’s activities because the new construction resulted in the plant operating for more hours each year, not an increase in hourly rate of emissions as required under the rules. AP has more.