The principal of the notes may be paid from: the county’s allocation of funds from the special account of the Bay Restoration Fund established under § 9–1605.2(h) of the Environment Article; and any other revenues that are pledged to the payment of the notes in the authorizing resolution. The interest on the notes may be paid from: any revenues, other than the county’s allocation of funds from the special account of the Bay Restoration Fund, that are pledged to the payment of the notes in the authorizing resolution; or money made available to the county to finance upgrades to on–site sewage disposal systems from: the State or a unit of the State, except for the funds from the special account of the Bay Restoration Fund allocated under this subtitle for grants and loans; the federal government or a unit of the federal government; or any other source. A county may pledge its full faith and credit and taxing power to the payment of the principal of and interest on the notes in the authorizing resolution. A county that makes a pledge under paragraph (1) of this subsection shall, in each fiscal year that any of the notes are outstanding, impose ad valorem taxes on all assessable property in the county at a rate and amount sufficient to pay the principal of and interest on the notes maturing in that fiscal year. If the proceeds from the taxes imposed in any fiscal year prove inadequate for the payment, the county shall impose additional taxes in the succeeding fiscal year to make up the deficiency.