Cal. Health and Safety Code § 79105

(a) Except as provided in subdivisions (b) and (c), any potentially responsible party at a site, or any person who has notified the department of that person’s intent to undertake removal or remediation at a site, shall reimburse the department, pursuant to Chapter 6.66 (commencing with Section 25269) of Division 20, for the costs incurred by the department for its oversight of any preliminary endangerment assessment at that site. (b) This section does not apply to any notice of intent submitted to the department prior to July 1, 1998. Any person who submitted a notice of intent prior to July 1, 1998, shall pay the fee, if not already paid, as required by Section 25343 as it read on December 31, 1997, unless the department and that person mutually agree to enter into a reimbursement agreement in lieu of any unpaid portion of the required fee. (c) The changes made in Section 25343 by Chapter 870 of the Statutes of 1997 do not require amendment of, or otherwise affect, any agreement entered into prior to July 1, 1998, pursuant to which any person has agreed to reimburse the department for the costs incurred by the department for its oversight of a preliminary endangerment assessment.