70 ILCS 2605/9.6
Without submitting the issuance thereof to the legal voters of the Sanitary District for approval the corporate authorities thereof by ordinance may authorize bonds for the purpose of refunding the principal of its bonds whenever proceeds of taxes levied therefor shall not have been received in time to pay such principal at its maturity.
The refunding bonds may be exchanged par for par for such bonds or refunding bonds may be sold at not less than their par value and the proceeds received shall be used to pay such bonds and in any event the bonds refunded shall be cancelled upon the delivery of the refunding bonds. The refunding bonds shall mature 10 years from their date and may bear interest at a rate not exceeding that permitted by "An Act to authorize public corporations to issue bonds, other evidences of indebtedness and tax anticipation warrants subject to interest rate limitations set forth therein", approved May 26, 1970, as amended. After the cancellation of the bonds refunded the money thereafter received from the proceeds of the delinquent taxes, the non-collection of which made necessary such refunding, shall be paid into a special sinking fund for the payment of the refunding bonds and may be used by the treasurer of such sanitary district in the purchase of such refunding bonds at not to exceed their par value and accrued interest and any refunding bonds so purchased shall be cancelled and the tax next to be extended for payment of the refunding bonds shall be reduced in the amount of the refunding bonds so cancelled. If any such money shall not have been used in the purchase of refunding bonds, such money shall be set aside in a fund to be used for payment of the interest and principal of such refunding bonds as the same shall mature and the tax or taxes next to be extended for such payment shall be reduced by the amount so set aside. An ordinance shall be adopted annually during the term of the refunding bonds, finding the amount of refunding bonds so purchased from the proceeds of such delinquent taxes, and the amount of money on hand received from the collection of such delinquent taxes not used in purchasing refunding bonds, and directing the reduction in that amount of the tax next to be extended for payment of the refunding bonds and a certified copy thereof shall be filed in the office of the county clerk, whereupon it shall be the duty of such official to reduce and extend such tax levy in accordance therewith.
70 ILCS 2605/9.6