Cal. Public Resources Code § 41821.7

(a) The department may issue an administrative complaint to any person on whom civil liability may be imposed pursuant to this article. The complaint shall allege the acts or failures to act that constitute the basis for liability and the amount of the proposed civil liability. The complaint shall be served by personal service or certified mail and shall inform the party so served that a hearing shall be conducted within 60 days after the party has been served, unless the party waives the right to a hearing. (b) If the party waives the right to a hearing, the department shall issue an order setting liability in the amount proposed in the complaint unless the department and the party have entered into a settlement agreement, in which case the department shall issue an order setting liability in the amount specified in the settlement agreement. If the party has waived the right to a hearing or if the department and the party have entered into a settlement agreement, the order shall not be subject to review by any court or agency. (c) Any hearing required under this section shall be conducted by an independent hearing officer according to the procedures specified in Chapter 5 (commencing with Section 11500) of Part 1 of Division 3 of Title 2 of the Government Code, except as otherwise specified in this section.