Attachment K - HSTP Design

5.1 Installation Notes.

All installation works, components and fittings must comply with AS/NZS 1547—
2012 On-site Domestic Wastewater Management, and the Queensland Plumbing and
Wastewater Code, and the local authority.

Soils are susceptible to damage during the construction and installation processes.
The natural integrity of the existing soil conditions of the Land Application Area must
be preserved at all stages of the proposed development. Damage to the existing soil
profile must be avoided. Do not over work the soil profile. The system must not be
constructed or installed during or immediately after periods of wet weather.

Land Application Facilities and treatment systems/service plants (wastewater
treatment unit and disposal areas) must be located with good and clear access for
servicing and maintenance requirements.

All supply line excavations and trenching shall be backfilled with interceptors or
extended below the Land Application Area to inhibit surface water infiltration.

A reserve area shall be made available on-site for future use and is to be protected
from any development that would prevent its use in the future.

Particular care should be taken with the layout and construction of supply line
trenching/pipework, as with all drainage, plumbing and electrical trenches to inhibit
surface water infiltration along and into the Land Application Area. All supply line
excavations and trenching shall be backfilled with interceptors.

Particular care should also be taken with the layout and construction of the Land
Application Area trenching/pipework so that released effluent cannot travel back
along trenching causing excessive soil moisture in some areas.

Correct pipe layout and Land Application Area construction/installation is an essential
part of our recommendations and design. If the site is not prepared in accordance
with our design, or is prepared inadequately or is prepared poorly, inefficiencies may
occur and we do not take responsibility for the consequences in such cases and we
will make an additional charge if as a result, more testing, re-designing or re-writing
of the report is necessary.

 

Unearthed Geotechnical P/L. 7 Design Report 023-038