Cal. Public Resources Code § 45019

At least 10 days prior to the date of issuance of an enforcement order which is not for an emergency, or within five days from the date of issuance of an enforcement order for an emergency, or within 15 days from the date of discovery of a violation of a state law, regulation, or term or condition of a solid waste facilities permit for a solid waste facility or disposal site, which is likely to result in an enforcement action, the following agencies shall, to the extent that the enforcement action involves a violation that may also be under the jurisdiction of another state regulatory agency, provide a written statement providing an explanation of, and justification for, the enforcement order or a description of the violation in the following manner: (a) The enforcement agency, as appropriate, shall provide the statement to the regional water board, the board, the air pollution control district or air quality management district, and the Department of Toxic Substances Control. (b) A regional water board, as appropriate, shall provide the statement to the enforcement agency, the board, the air pollution control district or air quality management district, and the Department of Toxic Substances Control. (c) An air pollution control district or an air quality management district, as appropriate, shall provide the statement to the enforcement agency, the board, the regional water board, and the Department of Toxic Substances Control. (d) The Department of Toxic Substances Control, as appropriate, shall provide the report of inspection required by paragraph (1) of subdivision (c) of Section 25185 of the Health and Safety Code to the enforcement agency, the board, the regional water board, and the air pollution control district or air quality management district.