I wasn't aware Polymer Innovation worked in pond sealing - no clue of what polymer they use but it's unfortunate their product didn't work. We're successful on over 90% of our projects but we use a different polymer combination most likely.

A dozer will not compact material to affect a seal, they are meant to bridge material, not compact it. I would excavate, apply a polymer liner, then a few 6" lifts of high plasticity clay compacted with a sheepsfoot roller or at the very least rubber wheel equipment up to 18-24" depth per Scott above.

You're welcome to reach out anytime - hope whatever you do works for you. Leaking ponds stink.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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