Tenn. Code § 69-5-921
The county legislative body has the authority to issue refunding bonds as provided for in this part, upon the filing with the county legislative body of a petition duly authorized and signed by the board of directors of the district whose outstanding bonds are desired to be refunded. The petition, among other appropriate recitals, shall set forth a description of the outstanding bonds proposed to be refunded, the reason for such refunding, whether or not the holders of the outstanding bonds have consented to the refunding of the bonds, the amount of refunding bonds proposed to be issued, including the proposed date or dates when such refunding bonds are to mature. The petition shall request the county legislative body, upon the giving of the notice and upon the holding of the hearing provided for in § 69-5-924, to direct the issuance of such refunding bonds and to provide for the levy of taxes for the payment of the refunding bonds and the interest on the refunding bonds.
T.C.A. § 69-5-921