AA1384_Effluent Report_final

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                    Therefore, assuming 150L/person/day the outflow is calculated as:

                              150L/person/day x 5 persons = 750 L/day

                    In accordance with AS/NZS 1547:2012, the Design Loading Rate (DLR) of a
                    trench and bed system, based on sand (Category 1 soil), primary treated
                    effluent and a conservative rate, is approximately 20mm/day.

                         Therefore, required trench/bed areas for primary treatment = 37.5m2

                    The conservative rate of 20mm/day has been adopted for the primary
                    effluent calculations in accordance with Section L4.1 of AS/NZS 1547/2012
                    and due to the low nutrient retention capacity of sand.

                    However due to the sensitive nature of the surrounding environment (coastal
                    protection area) we recommend advanced secondary treatment, with trench
                    systems designed in accordance with the requirements of AS/NZS
                    1547:2012 to reduce the potential for nutrient runoff. The recommended
                    Design Loading Rate for Category 1 soil with secondary treatment is
                    50mm/d.

                    This would reduce the required trench bed areas to 15m2.


4.0        WASTEWATER TREATMENT AND DISPOSAL AREAS

The information below details the requirements for the siting of on-site wastewater treatment
in accordance with AS/NZS 1547:2012 and the Queensland Plumbing and Wastewater
Code 2013 (QPWC).

           4.1       Vertical & Horizontal Separation Distances

           The on-site sewerage facility shall incorporate measures to ensure that the effects of
           the onsite wastewater systems are contained within the property boundaries
           including, if necessary, the use of set-backs (AS/NZS 1547:2012 Clause 2.4.1(k)).

                                         Table 4.1
                  Recommended horizontal separation distances for subsurface land
                         application areas in accordance with the QPWC

                            Feature                               Recommended Horizontal Separation
                                                                         Distance (metres)

                                                                Up slope           Down slope         Level
      Property boundaries, pedestrian paths and walkways,             2                  4                    2
      recreation areas, footings of buildings and retaining
      walls footings.
      In ground swimming pool                                         6                  6                    6
      In ground potable water tank                                    6*                 6*                   6*
      * Note: For Primary effluent and in accordance with the Noosa Shire Council Planning Scheme Policy 24, distance
      from an in-ground potable water tank must be 15 metres.


           Swimming pools and in ground potable water tanks were not observed on site.




AA1384EFF
September 2016
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