Lance,

I've had the same problem that you are having. This is the 3rd. year and it still leaks about a 1/2 a day. I've had more clay hauled in and plan to dig a keyway this time. I took a witching rod and I believe I have found the fracture in the dam. My pond will leak down to a certain point, then will dry up below the dam site. I've used bentonite with not much help. If you find something that works please contact me.