The pile boring is of DMC (direct mud
circulation) type
using Bentonite drilling fluid, Mendola type pile rigs. The
boring is done by dropping bailer about 1m to 2.0m fall into
the borehole. Below ground level to resist the loose soil of
surface falling into the borehole. The bailer is removed, and
boring is proceeded by percussion hammering with a chisel
by pumping Bentonite slurry (specific gravity 1.03 to 1.08)
through DMC rods, at the same time the slurry whichever
dislodged in the bore flows out from the casing into the
settling chamber through the trenches made. This process is
continued until the boring is completed. Then the DMC pipes
and chisel are removed. After completion of boring, bore
depth should be measured by the sounding chain.