Got a call from our new Water Superintendent. He knew I had a metal detector. We had some major water problems and although the city owned their own metal detector, he could not find a vital valve he needed to turn on the water for a backup system. After some questions where I determined we were looking for a six inch round metal plate that was buried from 2 to 4 inches. It seemed that any metal detector could have found this. It seemed there was a lot of other small metal objects in the area, and they were losing valuable time digging small junk items. In about 2 minutes the valve was located and the water was on.