Cal. PRC § 4291.3

(a) Subject to any other applicable law, a state or local fire official, at their discretion, may authorize an owner of property, or the owner’s agent, to construct a firebreak, or implement appropriate vegetation management techniques, to ensure that defensible space is adequate for the protection of a hospital, adult residential care facility, school, aboveground storage tank, hazardous materials facility, or similar facility on the property. The firebreak may be for a radius of up to 300 feet from the facility, or to the property line, whichever distance is shorter.

(b) The director may authorize an owner of a property not listed in subdivision (a) to construct a firebreak, or implement appropriate vegetation management techniques, within a radius of up to 300 feet from a structure, or to the property line, whichever distance is shorter, if it is determined by the director as necessary to protect life, property, and natural resources from unreasonable risks associated with wildland fires.