That wont be too difficult, you will have to dig a much larger, wider ditch with your trackloader so that you can cover all of it with the trackpads to compact it in in lifts, blending it well with the clay in the sidewalls in a rough surface, no smooth cuts or surfaces, try to get the inside, water side, filled and compacted with your best cleanest clay you have available with no foreign materials or topsoil mixed in, the outside half isn't quite as critical, you can use up some of your mixed dirt there,, I have resealed quite a few of them that way with no problems.
