Changed plans when I got to the garage. Saw a bag of bentonite that we'd used in water holes for deer. The vertical stack was about 24" above the dirt/grade of the pond and about 20" below where the water level will ultimately be.

Looked/felt like someone tried to seat the vertical pipe of the overflow with a spud bar or something and got a little rowdy with it. 3" long piece of plastic on a high part of a rib was broken.

2 handfuls of bentonite and it had almost stopped. I put some on the inside as well, and it pretty well quit.

So as the saying goes, if a little is good, a lot is much better. I packed about a 12" x 24" square around the outside of the pipe, and overdid the inside as well. Then I dumped the remainder of the bag below the gash and it naturally piled up above the outside hole.

Had to be out there again this afternoon and check it. it had rained some, and the stuff had held. So i dumped 4 more bags around the overflow. the entire perimeter. The dry product was above the grade of the cut.

I did get a bunch "into" the cut as well, so hoping we're ok. They seal wells with the stuff, and its done fantastic with our waterholes in the past. Here's hoping.