The skid pad itself is a large area of smooth concrete, surrounded by a number of irrigation pumps and nozzles to flood various areas so the trucks hydroplane and lose traction.
During the course of videotaping, I took position a bit too close to the action... as you can see in this short clip:
I have hundreds of pics and 25 minutes of video I shot. When I get time I'll see if I can get some of the highlights uploaded.