Tank Installation procedure
- Select a suitable location for the tank – this will be normally in ground lower than the properties being drained and allow for falls in site drainage.
- Check that no other structure or special access is required over the selected spot. Provision can always be made, if necessary, to place the tank on a roadway, provided that protective backfill is placed around it and a suitable duty manhole cover and frame is used over the opening.
- Check that no underground cables, pipes or service ducts, lie beneath.
- Evacuate the minimum opening in the ground to receive the tank and pipe work to be used. If a machine is used to remove the spoil, the sides of the excavation should be battened for stability and a sump left in one corner for dewatering purposes.
- The depth of excavation needs to be at most 500mm deeper than the overall tank (plus extra roof slab if applicable) depth. This extra depth is required to allow for the construction of a hardcore/concrete base.
- A de-watering pump may be required to control any ground water present.
- Some clean hardcore should be places and consolidated in the base of excavation. Usually this will need to be about 200mm thick, but in ground should be a minimum of 50mm.