Try a dive where you hit a 28-30 foot bottom and dive depth was 65 feet. Not much different than a dive into Navy Crude.drivsea:Depending on the weight of the object lost it is possible that it could be caught in the upper part of the ooze, otherwise it will be as far down as it can go or you can go...
that said this is not a scubadive- reserve tank or no. With loss of vis, unknown entanglement hazard, and a physical work load a limited air supply does not make sense.
Don't break it down into scuba or surface supplied dives. Break it down to recreational or non recreational dives. Most zero vis dives are no place for the majority of recreational trained divers. Others are a different story.
Gary D.