(1) No general obligation bond or other general obligation indebtedness may be refunded unless the holder thereof voluntarily surrenders the same for exchange or payment or the said indebtedness either matures or is callable for prior redemption under its terms within ten years from the date of issuance of the refunding bonds, and provision shall have been made in said refunding for paying the bonds or other indebtedness being refunded within said period of time.

(2) The refunding bonds may mature at one time or from time to time but not exceeding thirty years from the date of issuance of the refunding bonds. The interest rates on such refunding bonds shall be determined by the board.

(3) The principal amount of the refunding bonds may exceed the principal amount of the refunded bonds or other indebtedness being refunded if the aggregate principal and interest costs of the refunding bonds do not exceed such unaccrued cost of the indebtedness refunded except:

(a) To the extent any interest on the indebtedness refunded in arrears or about to become due is capitalized with the proceeds of said refunding bonds; or

(b) To the extent necessary to capitalize and pay, with the proceeds of said refunding bonds, the following:

(I) All costs and expenses of said refunding procedures;

(II) The amounts of the prior redemption premiums, if any, on the indebtedness being refunded; and

(III) Any interest in arrears or about to become due and payable.

(4) The principal amount of the refunding bonds may also be less than or the same as the principal amount of the indebtedness being refunded so long as provision is duly and sufficiently made for the payment of the refunded bonds.