The Commission may, by rule or order, authorize any intrastate pipeline to assign, without compensation, to any interstate pipeline or local distribution company all or any portion of such intrastate pipeline’s right to receive surplus natural gas at any first sale, upon such terms and conditions as the Commission determines appropriate.

For the effect of an authorization under subsection (a), see section 3431 of this title (relating to the coordination of this chapter with the Natural Gas Act [15 U.S.C. 717 et seq.]).

For purposes of this section, the term “surplus natural gas” means any natural gas which is determined, by the State agency having regulatory jurisdiction over the intrastate pipeline which would be entitled to receive such natural gas in the absence of any assignment to exceed the then current demands on such pipeline for natural gas.