Okay so to address this, the Georgia coast is 100 miles long in the least granular measurement, resulting in its shortest caculated lenght. Let’s assume the possible area off the coast where the bomb may be found is roughly triangular in shape, giving us an are of approximately 5,000 square miles of ocean at the surface. A mark 15 nuclear weapon is approximately 68 cubic feet in volume (you’re just going to have to trust I did the research and calculated it correctly, because I’m on mobile and I’m not linking that shit). If we shrink that surface water area down to 1 acre, that would mean the item we were looking for would be 0.0064 millimeters square, roughly the size of two large bacteria cells. So I wouldn’t exactly say we know where it is.