You hear the truck long before you see it. The low-pitched roar of the engine starts to rise, the sound of the gearbox becomes a whine and your body tenses as you feel the truck strain. Finally you see it. A dump truck appears around a bend in the road, grinding its way slowly up the concrete mountain.
From the street below, it almost looks like a big toy. Enormous pieces of concrete pillars are piled on it, as though a giant hand had snapped them off a crushed freeway and dropped them into the trucks bed. Forty feet above the Southeast Los Angeles street, as the truck reaches the summit, its huge tires leave a trail of dust in …