ATHENS, Ala. (AP) - The Nuclear Regulatory Commission has issued safety citations to the Tennessee Valley Authority for an incident that prompted an automatic shutdown at a plant in northern Alabama. Officials said Monday that an operator at the Browns Ferry Nuclear Plant near Athens failed to follow correct protocol in an incident that led to shutdown of Unit 2 in December. The reactor was going through testing after maintenance before the unplanned shutdown. Officials say the citation is of low to moderate safety significance and it won't change the level of oversight at the plant. Browns Ferry is under special federal oversight because of problems that were discovered in 2010. NRC officials say they'll inspect the plant to ensure that the Tennessee Valley Authority has taken appropriate corrective actions.