an option within the preferred embodiment is that the hollow inner chamber s contain s a secondary container s for example a refractory ceramic inner liner with properties other than sheer mechanical strength for example resistance to seawater corrosion or the high heat and corrosive nature of magma if the waste payload is borosilicate glass it will be nearly insoluble in seawater however care must be taken to prevent the contents from shattering upon projectile impact with the sea bottom the payload area may be sealed to minimize access of seawater to the payload contents alternatively it may be open on descent to equalize pressure and eliminate stress on the projectile structure due to high pressure at depth a plurality of payload areas within the projectile may be desirable to launch the projectile it is first attached to a barge or other floating platform and moved to a position directly over the target seafloor site then vertically erected with its leading edge pointed downwards toward the seafloor or lakefloor below fig1 the depth of the water above the east pacific rise is only 2 5 km and the thickness of the crust is 1 7 km and were such a u201c bullet u201d dropped in air it would be expected to impact at a speed of hundreds of km hr additional propulsion devices rockets can provide the thrust to even higher impact speeds of potentially thousands of km hr for example a thousand ton projectile with a very large solid rocket motor such as that used on the space shuttle 2 6e6 lbs force but with a much reduced propellant.