I was sucessful in attaching a permanent PVC Sleeve with valves on the Back side of the Dam. This has bought me a little time to solve the lake side Stack pipe issue. I feel more comfortable at Scuba diving, knowing the flow pipe is secure.
I am hoping that there is enough pipe left on the lake side in the vertical position to sleeve the old Steel with a 6 inch PVC. If the new PVC Sleeve holds enough water back, I am hoping to pump or fill the entire drain pipe with bentonite. I just don't know if I can pour the bentonite down the new PVC pipe to displace any water that might still in the pipe or do I have to open the back side vale and try to get the water out first?
The lake has been there for over sixty years. There is no easy way to get to the back of the dam with a vehicle now. Trees everywhere. I imagine during contruction, you could have easily driven a large buldozer across the dam with plenty of room on either side. Now, your lucky to get a 4 wheeler back there because of the vegetation and trees.