hi bill, welcome to PondBoss.

interesting geology there......16 feet of sand soils overlying clay soils which you will excavate into and use to seal the sides of the pond...correct?

it took me several minutes to try and visualize what yer describing and i'm not quite sure i got it.........but........let me convulute the description for my own purposes.....it sounds like you want to utilize the natural shallow groundwater (occurring in the sandy soils) from outside the newly sealed sides of the pond, and pump it (back) into pond from the drain tiles you installed before sealing everything up.

if the production of the shallow water table will support pumping i dont see why that wouldnt work, and i guarantee you no one else here has that kind of pond design, it is unique from what i've seen here and throughout my "pond" experiences.

anybody else have a comment on this? very interesting and different......take some pics of yer pond construction and post em up here (compressed some please) for folks to see, thanks for posting bill.

GSF are people too!