Trailing Suction Hopper Dredgers

A trailing suction hopper dredger operates very much like a floating vacuum cleaner. With a single or twin proboscis-like suction pipes, it pumps up materials from the sea floor and discharges them into a storage compartment, or hopper. On completion of loading the dredger sails to the disposal site where the cargo can be discharged, either by opening the doors or valves in the hopper bottom, by using the dredging pump to deliver to a shore pipeline, or directly to shore by using a special bow jet. This last technique is known as rainbowing.

Via Pruned, which also provides a link to this lifetime field list of geologic sites and experiences which I would love to complete. Somehow I think that will never happen...