Are they carryng the clay out past the end of the levee and tying it into good clay? I'd hate for them to put in a core trench, and then have the pond leak between the clay lining the basin of the pond and the core trench.

Think of a bowl with one side cut away. The bowl is your pond, the cut away side is the levee side. If you place the bowl against a board, then fill it, the water will leak out between the board and the bowl.

You get the idea......

IIRC, they lined the pond with clay and packed it when it was built, right?

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