Finally got test holes dug. Good and bad news. Lots of sand but also good clay mixed in. Some of the holes we dug down 10' had sandy clay and would barely hold form. Some would have 18" thick chunks for clay.
The water would rush into the holes when he dug about 4-5' down. Like a stream. He said it looks good not great. He said I could also keep it charged with a pump during high evaporation months bc my water level is so high.