wastewater design

5.0 DESIGN RECOMMENDATIONS

The four proposed cabins will utilize two identical wastewater facilities;
Cabins 1 & 2 will be serviced by one facility, and
Cabins 3 & 4 will be serviced by a second identical facility.

We recommend the installation of two Advanced Enviro-septic™ domestic
wastewater systems to treat the wastewater to advanced secondary quality.

We recommend the installation of two 3000It (min capacity) all-waste septic tanks to
treat the wastewater to primary quality (it should be noted that the local regulatory
authority may have larger minimum size requirements than those recommended).

The final location of the septic tanks will be determined on-site by variable
consequences (e.g. finished floor levels, distances, allotment configuration and
topographical constraints) over which we have little control. This final placement
may necessitate the use of pumps and pump wells to enable the Land Application
Area to be located above the septic tank. If the integrity and serviceability of the
existing septic tank is confirmed it may be retained. Alternatively it may be
decommissioned once the new septic tank is installed and commissioned.

We recommend further consultation to determine the adequacy of the final location
of the septic tanks and pump wells (if required) at the time of, or prior to construction
of the proposed dwelling.

Notwithstanding the final location of the septic tanks and the Land Application Areas
particular attention should be paid to protecting any, or all pipework below driveways,
access tracks, or such trafficable areas.

The treated effluent is to be dosed into and along the Advanced Enviro-septic™ pipes.
Thus receiving treated effluent and residuals in a manner and at a rate that enables
their further treatment by natural in-soil stabilisation processes so that the resulting
clarified carriage water is environmentally and hygienically acceptable for
groundwater infiltration or evaporation and plant transpiration into the atmosphere.

Pump systems (if required) shall

e have a storage capacity equal to 50% of the daily flow allowance, and sufficient
to match the electrical starting requirements of the irrigation pump motor

e have performance characteristics that match the hydraulic characteristics of the
irrigation system

e have a discharge of at least 50% greater than the maximum 30-minute flow rate

e have a visual and audible alarm system (with muting ability) for breakdown
notification

e not be located adjacent to bedrooms, living rooms or recreational areas of
neighbouring properties

e be contained in an acoustic chamber to reduce noise emission of all equipment to
a level not exceeding 40 dB (measured as fast response at a distance of 1.0m),

e have incorporated into the facility pressure and/or velocity reduction fittings
installed sufficiently distant above the Advanced Enviro-septic™ piping.

 

Unearthed Geotechnical P/L. 6 Design Report 022-003