Mont. Code Ann. § 85-1-619

85-1-619 . Debt service fund -- pledge and administration of sufficient balance. (1) The legislature may levy, impose, assess, and pledge and appropriate to the renewable resource loan debt service fund any tax, charge, fee, rental, or other income from any designated source. The state reserves the right to modify from time to time the nature and amount of special taxes and other revenue pledged and appropriated to the renewable resource loan debt service fund, provided that the aggregate resources so pledged and appropriated are determined by the legislature to be sufficient for the prompt and full payment of the principal of and interest and redemption premiums when due on all bonds payable from that fund and provided that the pledge of the full faith and credit and taxing powers of the state for the security of all bonds is and remains irrevocable until they are fully paid.

(2) Money in the renewable resource loan debt service fund must be used to pay interest, principal, and redemption premiums when due and payable with respect to renewable resource bonds, and for bonds issued prior to 1985, to accumulate a reserve for the further security of the payments.

(3) After the reserve provided for in subsection (2) for bonds issued prior to 1985 has been accumulated in the renewable resource loan debt service fund, money at any time received in the renewable resource loan debt service fund in excess of that amount must be transferred by the treasurer to the natural resources projects state special revenue account.