Agreements between the railroad corporations and the Mississippi Department of Transportation which do not require payment of a portion of the revenue derived from the improved rail line to be paid by the railroad to the Railroad Revitalization Fund shall require that the railroad establish and maintain a separate railroad corporation fund to which a specified portion of the revenue derived from the improved rail line shall be credited and that these funds shall be used by the railroad for the rehabilitation or improvement of rail lines within the state. The terms and conditions governing the use of monies in the special railroad corporation fund shall be stipulated in the agreement. The agreement shall also stipulate a penalty for use of the funds in a manner other than as set forth in the agreement.