A huge 7 crew WW2 patrol bomber sank in 1949 after striking an obstruction in front of the Seattle Boeing Seaplane ramp at the south end of Lake Washington. The PBM Mariner currently rests in 80 feet of water in deep silt. The Navy has attempted salvage twice and both times personnel were injured in the attempts. Kees Beemster Leverenz who is a GUE dive instructor will talk about their recent dives and photogrammetry survey of this historic wreck. He will also talk about other ongoing documentation projects which he is working on.