When general obligation or revenue bonds are issued at high interest rates, they will have a callable feature allowing the county to recall the unpaid bonds or notes. In order to have funds to recall these bonds or notes, the county may issue refunding bonds. These bonds use the same pledge for security and replace the original issue with a lower rate of interest. By issuing the refunding bonds at a lower rate of interest, the county will save by paying less interest over the remaining term of the issue. T.C.A. §§ 9-21-901 through 9-21-1017.