The Secretary, acting through appropriate agencies and contractors, shall initiate and provide for the conduct of research and development in areas relating to methane-fueled vehicles, including but not limited to—

((1)) flammability and combustibility of methane under conditions likely to develop in storage or during vehicular use;

((2)) handling, storage, and distribution of methane for vehicular propulsion purposes;

((3)) comprehensive assessment of the relative hazards under identical circumstances of methane, propane, gasoline, and diesel fuel;

((4)) feasibility, economy, and efficiency of technologies for the production and recovery of methane from unconventional and supplemental sources, as provided for in other authorization Acts;

((5)) engine and fuel tank design including, but not limited to, optimum design for dual fuel capacity vehicles;

((6)) total vehicle construction and design;

((7)) the nature and quantities of emissions, and alterations in or alternatives to emission control systems presently in use; and

((8)) overcoming institutional barriers to widespread use including but not limited to restrictions on the transportation of methane for vehicular use through tunnels, and the potential expansion of the distribution of methane for vehicular purposes.