Cal. Health & Safety Code § 25395.103

(a) A bona fide ground tenant who seeks to qualify for the immunity pursuant to Section 25395.104 shall make all appropriate inquiries, and shall enter into an agreement pursuant to this article with an agency, and one or more entities that agree to take responsibility for implementing a site assessment and response plan pursuant to subdivision (b). The entity shall be one of the following:
1. (1) The site owner.
2. (2) A redevelopment agency.
3. (3) A city or county.
(b) Except as otherwise provided in subdivision (c), an agreement entered into pursuant to this article shall provide that the entity that accepts responsibility for the site assessment and response plan shall conduct a site assessment that substantially complies with the requirements of Section 25395.94 and implement a response plan that substantially complies with the requirements of Section 25395.96. For purposes of any health risk assessment, as specified in paragraph (2) of subdivision (a) of Section 25395.94, that is conducted for a site subject to this article, the intended site occupants shall include any person who is expected to reside at, work at, or otherwise physically cross onto, the boundaries of the site. Both the site assessment and the response plan shall be approved by the agency. Except as necessary to comply with provisions of this article that differ from Article 6 (commencing with Section 25395.90), agreements pursuant to this article shall substantially conform to agreements developed to implement Article 6 (commencing with Section 25395.90), and shall specifically include the agency cost reimbursement provisions required by subdivision (b) of Section 25395.93.
(c) An agreement entered into pursuant to this article shall provide that the bona fide ground tenant is responsible to the agency for only the portions of the site assessment and the portions of the response plan that the agency determines to be necessary to allow the site to be used for its intended purposes without unreasonable risk to the human health and safety of the intended site occupants. The bona fide ground tenant shall not be responsible to the agency for any other assessment or remediation of soil, soil gas, groundwater, or other media at the site; nor for any assessment or remediation adjacent to, or in the vicinity of, the site. The agreement shall also specify the portion of the site assessment and the response plan to be implemented by the party other than the bona fide ground tenant.
(d) Before finalizing the agreement, the agency shall notify other appropriate agencies, including the host jurisdiction. The agency shall keep, in a permanent archive, copies of all finalized agreements entered into pursuant to this article.
(e) Agreements entered under this article shall not be subject to Chapter 2 (commencing with Section 10290) of Part 2 of Division 2 of the Public Contract Code.
(f) A person who enters into an agreement under this article shall submit sufficient information to the agency for the agency to determine whether the site is eligible, whether the person meets the conditions to qualify as a bona fide ground tenant, and to prepare an agreement pursuant to this section.