E Creviced Formations: Earth Mantle Cover Over 30 Feet Thick – Oversized Drill Hole

Section 920.ILLUSTRATION E   Creviced Formations:  Earth Mantle Cover Over 30 Feet Thick – Oversized Drill Hole 1.   When a tremie pipe is used to grout, the diameter of the drill hole must be at least 3" larger than the outer diameter of the casing or coupling, whichever is greater. 2.   When grout is pumped through the inside of the casing, the diameter of the bore hole must be at least 2" larger than the outer casing or coupling, whichever is greater. 3.   The annular space must be grouted from the bottom of the casing to ground level.