We built a small point pounding rig years ago. It had a motor that ran a hydraulic pump that was tied into a cat head. The derek was about 7' high. We built it for this one specific job where we had to pound in a 2" well to 55'. Conservation would not allow any heavy drilling equipment on this guys property and we knew there was allot of layers of gravel for the first 25'. We used it allot in spots where you couldn't get any drilling equipment. That hammer that you were talking about for soil samples would work but what's even better is the drive weights with a hole through the center that allows the weight to move up in down. We used 300lb. hammers like that to drive 3 to 6 inch casing when we were test drilling. I wouldn't suggest that amount of weight to drive a 2" well point but a hammer like that with less weight is the way to go.