Cal. Health and Safety Code § 42451

(a) On its own motion, or upon the motion of the district board or the air pollution control officer, the hearing board may, after notice and a hearing, issue an order for abatement whenever it finds that any person is constructing or operating any article, machine, equipment, or other contrivance without a permit required by this part, or is in violation of Section 41700 or 41701 or of any order, rule, or regulation prohibiting or limiting the discharge of air contaminants into the air. (b) As an alternative to subdivision (a), the hearing board may issue an order for abatement pursuant to the stipulation of the air pollution control officer and the person or persons accused of constructing or operating any article, machine, equipment, or other contrivance without a permit required by this part, or of violating Section 41700 or 41701, or any order, rule, or regulation prohibiting or limiting the discharge of air contaminants into the air, upon the terms and conditions set forth in the stipulation, without making the finding required under subdivision (a). The hearing board shall, however, include a written explanation of its action in the order for abatement.