Jordan GreenStaff writerjgreen@oklahoman.comLike cars in a parking lot, dozens of idled locomotives are sitting in a railroad yard along Interstate 235 in Oklahoma City, waiting for the day when they’ll once again haul loads of freight from coast to coast.Those locomotives, which belong to the BNSF Railway Co., are being stored until rail traffic volumes in the United States return to pre-pandemic levels.Rail traffic volumes across the U.S.