Tricel NOVO EN6-50, User Manual

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Ballast*the plant by filling each chamber with clean water to a depth of 300mm and recheck the
pipe work levels. Commence backfilling with gravel as per 10.5.1 in layers of 225mm evenly
around the tank ensuring that there are no voids. Compact each layer ensuring the vibrating
machine does not come in contact with the plant. Continue filling the chambers whilst
backfilling, ensure that the progressive water level is no more than 300mm above the backfill
level.
• Continue to backfill until gravel has reached 50mm over the cylindrical body of the tank.
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Mount and seal manhole risers (if used)
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Complete backfilling with topsoil up to the max ground level line.
* Ballasting the plant is important to avoid the tank from lifting when backfilling.
10.5 Concrete installation:
A concrete surround must be installed in wet site conditions and sites where the inlet invert is between
810mm and 1310mm (plants with 500mm and 750mm risers).
A wet site is one where the water table may rise higher than the base of the Tricel
Novo tank.
The option of a reinforced concrete slab or deadman anchor may also be used. This should be designed
by an on-site structural engineer to suit site conditions.
10.5.1Tank base/plinth:
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Remove any soft spots or large stones and boulders.
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The base is constructed of a 50mm layer of suitably compacted gravel, covered with a 250mm
layer of semi dry concrete. Refer to 10.6.2
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Ensure that base is level and at the correct height to accommodate the incoming pipe work.
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It is important to maintain a completely dry excavation until the final pour of concrete is set. It
may be necessary to line the excavation with a continuous layer of 1200 gauge polythene to
maintain the integrity of the concrete.