Cal. PRC § 3636

“Unit agreement” means and includes, in addition to the unit agreement entered into pursuant to the provisions of Article 3 (commencing with Section 3640) of this chapter, any consent agreement or other agreement entered into in connection with, and supplemental to, such unit agreement, but does not include a unit operating agreement or any preliminary agreement confined to effectuating any exchange of interests in land which the parties to such preliminary agreement may desire. “Unit operating agreement” means an agreement, entered into by the working interest owners only, governing all operations performed by the unit operator pursuant to the unit agreement and the unit operating agreement for the production of unitized substances.