Except as provided in paragraph (2), whenever on the basis of any information, the Administrator determines that any person is in violation of any requirement of this subchapter, the Administrator may issue an order requiring compliance within a reasonable specified time period or the Administrator may commence a civil action in the United States district court in which the violation occurred for appropriate relief, including a temporary or permanent injunction.

In the case of a violation of any requirement of this subchapter where such violation occurs in a State with a program approved under section 6991c of this title, the Administrator shall give notice to the State in which such violation has occurred prior to issuing an order or commencing a civil action under this section.