The Administrator is hereby authorized to arrange for the payment of unpaid taxes, interest and penalties on a schedule of installment payments when the taxpayer has proved to the Administrator that, due to certain hardship conditions, he is unable to pay the full amount of the tax due. Such authorization shall not be granted until proper returns are filed by the taxpayer for all amounts owed by him under this chapter. Failure to make any deferred payment when due shall cause the total unpaid amount, including penalty and interest, to become payable on demand and the provisions of Sections 880.26 and 880.29 shall apply. (Ord. 1971-19. Passed 11-22-71.)