Quote Originally Posted by Grim Portent View Post
Through careful use of pumps we could build a tunnel down into the ocean itself and mine into the seabed for supplies to build the platform once it's started and break the anchor to the surface so it's able to be fully sealed at will.
Could you acomplish something similar by building a solid tower of rock and then removing its supports causing it to fall into the ocean, and then mining through the rubble to reach the sea bed? That's my current plan of action, unless its known to not work, then I'll spend time working on getting a stockpile of pump bits made up.