Cal. PRC § 4582.71

(a) A timber harvesting plan may not be approved if the appropriate regional water quality control board finds, based on substantial evidence, that the timber operations proposed in the plan will result in a discharge into a watercourse that has been classified as impaired due to sediment pursuant to subsection (d) of Section 303 of the Federal Water Pollution Control Act, that causes or contributes, to a violation of the regional water quality control plan.

(b) The exercise of a regional water quality control board’s authority pursuant to subdivision (a) may be delegated to the executive officer of that regional water quality control board as long as the executive officer’s determination is subject to review by that regional water quality control board upon request of the person that has submitted the timber harvesting plan or upon motion of that regional water quality control board.

(c) If the appropriate regional water quality control board makes a finding pursuant to subdivision (a), the executive officer of that regional water quality control board shall, before the close of the public comment period under Section 4582.7, notify the director in writing of the finding and advise the director that the plan may not be approved. If the issues that lead to a regional water quality control board’s finding pursuant to subdivision (a) cannot be resolved during the director’s determination period under Section 4582.7 or a longer period that is mutually agreeable to the director and the person that submitted the timber harvesting plan, the director shall deny the timber harvesting plan and return the plan to the person that submitted it. The director shall advise the person that submitted the timber harvesting plan of the reasons why the plan is being returned.