Cal. Pub. Res. Code § 3758

Where several contiguous parcels of land in one or different ownerships are operated as a single geothermal resources lease or operating unit, the term “outer boundary line” means the outer boundary line of the lands included in the lease or unit. In determining the contiguity of any such parcels of land, no street, road or alley lying within the lease or unit shall be deemed to interrupt such contiguity.