70 ILCS 1842/95

(a) All funds deposited by the treasurer in a bank or savings and loan association shall be placed in the name of the Port District for the participating municipality and shall be withdrawn or paid out only by check or draft upon the bank or savings and loan association, signed by the treasurer and countersigned by the chief elected official of the municipality in which the funds were derived for the Port District or in the same manner as required by the municipality within the municipality's ordinances. A bank or savings and loan association may not receive public funds as permitted by this subsection unless it has complied with the requirements under Section 6 of the Public Funds Investment Act. (b) If an officer whose signature appears upon a check or draft issued pursuant to this Act ceases to hold his or her office before the delivery of the check or draft to the payee, his or her signature nevertheless shall be valid and sufficient for all purposes with the same effect as if he or she had remained in office until delivery of the check or draft.