Cal. Health and Safety Code § 25292.2

(a) All owners and operators of an underground tank system shall maintain evidence of financial responsibility for taking corrective action and for compensating third parties for bodily injury and property damage caused by a release from the underground tank system, in accordance with regulations adopted by the board pursuant to Section 25299.3. The regulations shall include a schedule that requires that financial responsibility requirements are phased-in for all underground storage tank systems on or before October 26, 1990. (b) If the owner and the operator are separate persons, either the owner or the operator shall demonstrate compliance with subdivision (a). (c) An owner may comply with this article by entering into an agreement with the operator of the tank requiring the operator to demonstrate compliance with subdivision (a). However, both the owner and the operator are in violation of subdivision (a) if evidence of financial responsibility is not established and maintained in accordance with this article.