Bob-O
My 2 cents; I think you need to get the water off where you are going to try this. Then you would need the blast to start in one spot and move by using time delay.
The explosion will follow the path of least resistance.
The water has to be gone or you'll have to use to much blast to push the water out of the way to move any material.
The time delay works to move material like this,
you blast off several holes, (holes would need to be drilled or dug on a grid) and that material goes path of least resistance, up. A split second later the drilled holes next to the blown hole go off and the path of least resistance is sideways up. Then the drilled holes next to that blast sideways up, and so on. This can work to leave a hole on one end of the shot as deep as the holes were drilled and will leave a mound on the other.
Everybody is right that you can't just blast a hole and expect the material to go into the air or water and disappear without using way way to much explosives.


Make it look easy,
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