ATLANTA - Thomas Settles grew up on a dirt road in Edgefield, S.C., a road so crummy it washed out completely after a heavy rain and he sometimes couldn't get to school. Summers were spent choking at the road's dust. Now 53, Settles owns a paving company in Atlanta and is on a mission to save poor Southerners from the indignities he grew up with. He's out to make dirt roads as good as paved ones. "Look at this," he says, holding up a plastic jug of molasses-looking brown stuff. "This is all it takes." The brown stuff is an...