California Code, Health and Safety Code - HSC § 79825

(a) The hazardous substance release occurred on or after the date that the owner acquired the property.

(b) The hazardous substance release occurred before the date that the owner acquired the property and, at the time of the acquisition, the owner knew, or had reason to know, of the hazardous substance release.

(c) The environmental assessment applicable to the property was not properly carried out, was fraudulently completed, or involves the negligent or intentional nondisclosure of information.

(d) The hazardous substance release was discovered on or after the date of acquisition and the owner failed to exercise due care with respect to the release, taking into consideration the characteristics of the hazardous substance in light of all relevant facts and circumstances.