Public Resources Code § 21080.21

This division does not apply to any project of less than one mile in length within a public street or highway or any other public right-of-way for the installation of a new pipeline or the maintenance, repair, restoration, reconditioning, relocation, replacement, removal, or demolition of an existing pipeline. For purposes of this section, “pipeline” includes subsurface facilities but does not include any surface facility related to the operation of the underground facility.