All sums received through the payment of fees or the forfeiture of bonds shall be placed in the state treasury and credited to a special agency account to be designated as the Tennessee surface mine reclamation fund. This fund, appropriations for which are also authorized, shall be available to the commissioner for expenditure for the reclamation and revegetation of land affected by surface mining operations, including lands so affected prior to enactment of this part; provided, that the proceeds from the forfeiture of any bond shall be used to the extent required in completing reclamation and revegetation of the area with respect to which the bond was posted. The fund shall also be available to the commissioner for expenditures consistent with §59-8-104. Any unencumbered and any unexpended balance of this fund remaining at the end of any fiscal year shall not lapse but shall be carried forward for the purpose of reclamation and revegetation of land as provided in this section until expended.