I hunted around it years ago when it was still an orange grove, instead of big-bucks houses. It was a site that had been an old homestead that had burned. I don't remember finding much.
Remember that anything found in the lake that is man-made and over 50 years old will be illegal to even touch...and because of all the native sites around there, they do watch the area....right up until the bulldozers come in and bury everything and destroy the sites for good.