When I lived on Pine Island Fl there was a small Island of the N.W tip of the island that you could walk to at low tide. My wife and I took our 9000 Teknetics detectors out there and hunted. At one spot we got a strong gold signal. With our small trowels we dug. The deeper we got the stronger the signal but we knew we needed shovels. The next day we went back with shovels and dug down to about 4' when water started pouring in.
The next day I talked to a friend of mine who owned a dock building company and he said he had a pump. The next day the 4 of us went to the island and pumped out the hole and started digging again. When we got down to about 6' the walls started filling up the hole again. We worked for about 8 hrs and called it a day. Using a long bar we hit something about 2' below where we stopped digging and felt like wood or metal and was about 3' x 2'. The gold signal was even stronger.
The next day we came back and the whole hole had collapsed and what was left was filled with water. At that point we all had to get back to work so we just left it and never went back. I still wonder what's down there...
