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Excavation guide
Groundworks
A square stepped excavation may be used due to the physical shape of the WPL
Diamond plant. Allow adequate clearance for all pipes and any other connections
for the tank.
Base construction
Both the base on which the tank sits and the backfill material must support the tank
when full to prevent it from sinking.
Backfill material
WPL recommends using dry-lean concrete to approximately 150mm below the tank lid.
Under no circumstances should the backfill material be vibrated to achieve
compaction. Do not use vibrating pokes. Also, the backfill pour must not outpace
the ballasting of the tank with water. Backfill outside can only equal the level of
the water inside.
WATER FROM HOSE
WATER FROM HOSE
DMS MODELS
300mm
750mm
150mm
200mm
DMC MODELS
450mm
STEP 1
MAKE SURE THE DIAMOND BASE IS INSTALLED READY.
FOR THE DIAMOND TANK TO BE LOWERED ON TO.
NOTE:- THE BASE CAN BE SEMI DRY CONCRETE TO.
REDUCE THE CHANCES OF PIERCING.
STEP 3
FILL THE TANK WITH WATER.
AND BACKFILL IN EQUAL STAGES.
STEP 2
ENSURE THE DIAMOND IS LEVEL.
ADD WATER INTO THE TANK AT THE SAME TIME WHEN.
BACK FILLING. ENSURE THE WATER LEVEL IS THE SAME.
HEIGHT AS THE BACKFILL.
STEP 4
BACKFILL TO A LEVEL 150mm BELOW THE MANHOLE LID.
Illustration guide only
