By Sarah Sheppeck Edward coughed as the 507 to Oak Ridge slowed to a stop in front of him. The bus shuddered as it struggled to break, belched thick gray exhaust toward the cars behind. He gestured to the woman standing beside him—an attempt to indicate that she should board first. She shook her head, put up her hand in silent protest, but boarded ahead of him anyway. Edward followed, tapping his boots against the bottom step of the stairway to dislodge some of the dirt. He dropped a handful of meticulously counted change into the collection slot and took…