A. Notwithstanding any other provision of the Air Quality Control Act, if the secretary or the director determines that a source or combination of sources presents an imminent and substantial endangerment to the public health or welfare or to the environment, he may bring suit in the district court for the county in which the source is located to restrain immediately any person causing or contributing to the alleged air pollution to stop the emission of air contaminants causing or contributing to such air pollution or to take such other action as may be necessary.

B. If it is not practicable to assure prompt protection of the public health or welfare or the environment by commencement of a civil action, the secretary or the director may issue orders necessary to protect the public health or welfare or the environment. An order shall be effective for a period of not more than twenty-four hours, unless the secretary or the director brings a civil action before the expiration of twenty-four hours. If the secretary or the director brings an action within that time, the order shall be effective thereafter for forty-eight hours or for such longer period as may be authorized by the court pending litigation.