Requiring the commissioner of transportation (DOT) to develop a corridor improvement plan for certain railroad grade crossings in the southern portion of the state, requiring the plan to include certain grade separation recommendations; requiring the commissioner to develop minimum recommendations for crossings with moderate levels of exposure or hazard and to develop additional recommendations based on cost benefit analyses and addressing certain safety and importance issues; requiring the commissioner to consider current and projected train and vehicle traffic volumes in developing the corridor improvement plan to provide future programming and planning guidance to affected railroad companies and local government units and the department; requiring the commissioner to provide opportunity for affected railroad companies and local government units to participate in developing the corridor improvement plan and to allow local units the opportunity to review the plan before executing agreements with railroad companies; requiring the commissioner to prepare a final plan for submission to area transportation partnerships established within the corridor area (rla)