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7. Installation
7.7
Backfilling the infiltration system
Before backfilling the trench, all inlets, vents and
shafts must be connected. Ensure that the geotex-
tile is not pulled apart. Overlaps must remain in
place when backfilling.
The blocks must not be driven over directly with
construction machinery.
When the trench is being backfilled, the installation
conditions described in section 6.3 must be ob-
served and adhered to.
Unless the installation con-
dition necessitates specific backfilling materials, the
compacted drainage system is backfilled with
coarse-grained, compactable loose ground such as
gravel, crushed stone, or sand, filling it at least up
to the top edge of the drainage system. Any exca-
vated earth or similar material can be used for back-
filling above the top edge of the drainage system if
required. It is essential to remove sharp objects,
larger stones, or any foreign objects during this pro-
cess.
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