piphw- main dam package - additional works - investigation, survey, preparation of designs & drawings etc., (1) construction of rcc diaphragm wall end cutoff for spill channel (2) vibro stone columns and deep soil mixing in gap-ii (3) construction of ecrf dam gap-i including diaphragm wall cutoff vibro stone columns and deep soil mixing, concrete dam gap-iii and (4) slope protection works on both sides of spillway and spill channel etc., of polavaram irrigation project - l.s contract system..
