The present disclosure generally relates to a system and method for installing a tubular element, such as a suction pile, in a bottom of a body of water. The system comprises a tubular element and a deintensifier in fluid communication with the tubular element. The deintensifier is configured to be exposed to an ambient pressure external to the tubular element and reduce pressure within the tubular element. The method comprises lowering the tubular element to the bottom of the body of water, filling the tubular element with water at ambient pressure, and exposing the water within the tubular element to a deintensified external ambient pressure so as to withdraw the water out of the tubular element.

A device for launching subsurface mining vehicle into a water mass from a docking well of a floating vessel, and/or recovering said vehicle from the water mass is disclosed. The device comprises a docking frame that is hinge mounted to the vessel, and that comprises first mining vehicle engaging means for guiding the mining vehicle along a longitudinal direction of the frame into the water. The docking frame operatively engages with drive means for tilting the frame in a vertical plane between a substantially horizontal mining vehicle docking position and a substantially vertical mining vehicle launching or recovery position. The device further comprises third engaging means for guiding the mining vehicle when the vehicle extends at least partly underneath a base of the vessel. The device allows lowering or recovering subsurface mining vehicle in a controlled manner.

An apparatus and technique for underwater storage and deployment of a fishing line and buoy includes a cylinder coupled to a fishing apparatus. A buoy is attached to a buoy line coupled to the fishing apparatus and the buoy line and buoy are stowed within the cylinder in a first position. A holding mechanism holds a top perimeter of the cylinder closed until intentionally released. Upon release of the holding mechanism, the buoy and buoy line escape the cylinder. The buoy then pulls the buoy line to the surface where the fishing apparatus can be recovered by the fisher.