August AT-10, Manual

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WASTEWATER TREATMENT
PLANT MODEL AT6 - AT50
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3. Construction:
3.1. Earthwork must be carried out strictly in accordance with the normative acts in force and the
technical or work project of the building.
3.1.1 Pits for the Units are excavated in two steps:
3.1.2 In the first stage, the pit is excavated by an excavator, leaving about a 20-30 cm thick layer to
the design altitude.
3.1.3 At the second stage, the layer of 20-30 cm is dug manually. This method of earthwork will en
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sure the installation of the Unit on undisturbed soil.
3.5.
IMPORTANT!
If there is high groundwater on the construction site, the Units are partially buried,
i.e. to a certain depth, and the remaining part is covered with a gravel-sand mixture (0.4 mm fraction)
by forming a dyke. In this case, the pumping stations for sewage lifting should be installed upstream
of the Units. It is necessary to raise about 0.30 m of undisturbed soil to the groundwater level.
3.6. The Unit is lowered into the pit using typical lifting mechanisms.
3.7. After lowering the Unit into the pit and checking the design position (depth, horizontal/vertical
3.2.
IMPORTANT!
Pit depth depends on the depth of the
wastewater pipe at the installation location. The pit must
have a funnel shape: the diameter of the pit must be at
least 1.5 m wider than the diameter of the device at the
top and 0.5 m wider than the diameter of the device at
the bottom.
3.3.
IMPORTANT!
Installations must be mounted on a reinforced concrete base in order to
ensure horizontal and vertical levelling of the Units. A concrete base (about 15-20 cm thick, with
reinforcement mesh) is concreted on the compacted soil, or prefabricated reinforced concrete soles
can be used.
3.4. Units can be fully or partially buried (depending on the groundwater level).
IMPORTANT!
Units are mounted above groundwater level (see Principal diagram 2).
Principal diagram 2
example