Stock and FotRSU both have the area as roughly -19m to -20m, but it might go slightly shallower. Kind of tough to say in the ME, even fully zoomed. With astvitaliy1982 Terrain file added, there is the usual "square" that shows on the map, but its southwest corner, by where USS No-Go would have been, registers upwards to +4m for a pinch of a "blip" once, but usually I could only get 1-2m. I have not viewed it in the game yet.
