18 CFR 284.266: Rates and charges for interstate pipelines.

(a) Transportation rates—(1) Rate on file. If an interstate pipeline has on file with the Commission an effective transportation rate schedule that conforms to § 284.10, it must use volumetric rates based upon fully-allocated costs and adjusted only for time and distance.

(2) Rate not on file. If an interstate pipeline does not have on file with the Commission a transportation rate schedule that conforms to § 284.10, it may:

(i) Base its rates upon the methodology used in designing rates to recover the transmission and related storage costs included in one of its then-effective sales rates schedules; or

(ii) Use the rates contained in one of its transportation rate schedules on file with the Commission which the interstate pipeline determines covers service comparable to transportation service authorized under this subpart.

(b) Interstate pipeline costs excluded from rate base. An interstate pipeline may not include in its jurisdictional rate base any cost associated with facilities installed and operated in connection with an emergency natural gas transaction unless a certificate of public convenience and necessity has been issued authorizing the costs. Absent a certificate, such facilities may only be used to conduct emergency natural gas transactions or transactions authorized under section 311 of the NGPA.