Abstract: Systems and methods for filling submerged voids with a foam-fluidized fill material in an efficient and economical manner are disclosed herein. The foam fluidized fill material is a granular solid material fluidized with a foam. The foam-fluidized fill material is pumped or gravity-fed through an insertion tube into the submerged void. The insertion tube terminates at a point lying below a surface of the liquid within the void. Since the foam-fluidized fill material is heavier than the liquid, the foam-fluidized fill material exiting the insertion tube sinks to the bottom of the void and expands laterally at the bottom of the void displacing the liquid. The liquid is forced upward and out of the void where it may be collected. Further, as the fill material fills the void, the foam dissipates and the fill material self compacts, making the filled void sufficiently load bearing.

Abstract: Systems and methods for filling submerged voids with a foam-fluidized fill material in an efficient and economical manner are disclosed herein. The foam fluidized fill material is a granular solid material fluidized with a foam. The foam-fluidized fill material is pumped or gravity-fed through an insertion tube into the submerged void. The insertion tube terminates at a point lying below a surface of the liquid within the void. Since the foam-fluidized fill material is heavier than the liquid, the foam-fluidized fill material exiting the insertion tube sinks to the bottom of the void and expands laterally at the bottom of the void displacing the liquid. The liquid is forced upward and out of the void where it may be collected. Further, as the fill material fills the void, the foam dissipates and the fill material self compacts, making the filled void sufficiently load bearing.