(a) At any time, the state board may, on its own motion, review the regional board’s failure to act under this article.
(b) The state board may find that the failure of the regional board to act was appropriate and proper. Upon finding that the failure of the regional board to act was inappropriate or improper, the state board may direct that appropriate action be taken by the regional board, refer the matter to another state agency having jurisdiction, take appropriate action itself, or take any combination of those actions. In taking any action, the state board is vested with all the powers of the regional boards under this division.