Cal. Health & Safety Code § 78440

(a) Any officer or employee of the department, a representative of the director, or a person designated by the director may require any person who has or may have information relevant to any of the following matters to furnish the information, upon reasonable notice:
1. (1) The identification, nature, and quantity of materials that have been, or are, generated, treated, stored, or disposed of at a hazardous substance release site or that have been, or are, transported to a hazardous substance release site.
2. (2) The nature or extent of a release or a threatened release of a hazardous substance at, or from, a hazardous substance release site.
3. (3) The ability of a person to pay for or to perform a response action, consistent with Section 104(e) of the federal act (42 U.S.C. Sec. 9604(e)).
(b) Any person required to furnish information pursuant to this article shall pay any costs of photocopying or transmitting the information.
(c) A person who is required to provide information pursuant to subdivision (a) shall, in accordance with Section 78455, allow the officer, employee, representative, or designee, upon reasonable notice and at reasonable times, to have access to, and copy, all records relating to the hazardous substances for purposes of assisting the department in determining the need for a response action.