66 Pa. C.S.A. §507 & §508
§ 507. Contracts between public utilities and municipalities.
Except for a contract between a public utility and a municipal corporation to furnish service at the regularly filed and published tariff rates, no contract or agreement between any public utility and any municipal corporation shall be valid unless filed with the Commission at least 30 days prior to its effective date. Upon notice to the municipal authorities, and the public utility concerned, the Commission may, prior to the effective date of such contract or agreement, institute proceedings to determine the reasonableness, legality or any other matter affecting the validity thereof. Upon the institution of such proceedings, such contract or agreement shall not be effective until the Commission grants its approval thereof.
§ 508. Power of the commission to vary, reform and revise contracts.
The commission shall have power and authority to vary, reform, or revise, upon a fair, reasonable, and equitable basis, any obligations, terms, or conditions of any contract heretofore or hereafter entered into between any public utility and any person, corporation, or municipal corporation, which embrace or concern a public right, benefit, privilege, duty, or franchise, or the the grant thereof, or are otherwise affected or concerned with the public interest and the general well-being of this Commonwealth. Whenever the commission shall determine, after reasonable notice and hearing, upon its own motion or upon complaint, that any such obligations, terms, or conditions are unjust, unreasonable, inequitable, or otherwise contrary or adverse to the public interest and the general well-being of this Commonwealth, the commission shall determine and prescribe, by findings and order, the just, reasonable, and equitable obligations, terms, and conditions of such contract. Such contract, as modified by the order of the commission, shall become effective 30 days after service of such order upon the parties to such contract.