Reference Documents

                                                   PROPOSED SUBDIVISION
                                                   41 TALLOWWOOD PLACE, BLACK MOUNTAIN

            The nominal land application area as shown in Figure 1 would therefore be appropriate, and it is assessed that
            that there is enough room to site the wastewater irrigation area with the necessary setbacks on the new lot.
            The need for a reserve area is generally applied to septic tank systems, producing low quality (Primary
            Standard) effluent, due to increased potential for fowling and failure of the trenched land application area to
            occur. As the use of aerated wastewater treatment systems is proposed, which are capable of delivering high
            quality (Secondary Standard or better) effluent, the risk of fouling and system failure is negligible. Proposed
            wastewater irrigation can be easily repaired in-place as required, so the addition of a separate reserve area is
            not warranted.
            7.4.2             System Positioning
            Positioning (‘setbacks’) of the land application systems must be in accordance with the horizontal and
            vertical setback distances recommended in Tables T2, T3 and T5 of the Queensland Plumbing and
            Wastewater Code 2019, as summarised in Tables 4 and 5 below.
            Table 4: Setbacks for subsurface land application area for on-site sewage treatment plant
                                                                                                                           Horizontal separation distance
               Site Feature
                                                                                                                     Upslope           Downslope            Level


              Property boundaries, pedestrian paths, walkways, recreation areas, retaining wall, and
                                                                                                                          2m                4m                2m
              footings for buildings and other structures.


              Inground swimming pools.                                                                                                    6m


              Inground potable water tank.
                                                                                                                                          6m
              (Secondary standard effluent or better)

            Note:     Distances measured from the edge of trench/bed excavation or subsurface irrigation distribution pipework to the nearest point of the feature.



            Table 5: Setback distances for on-site sewerage facilities (Protection of surface and groundwater)
                                                                                                                           Separation Distance

              Site Feature
                                                                                                        Advanced Secondary                  Secondary Effluent
                                                                                                             Effluent

            Surface Waters:
              Top of bank of permanent or intermittent water course, lake, bay or
                  estuary;
              Top water level of a surface water source used for agriculture,                                     10 m                              30 m
                  aquaculture or stock purposes;
              Open stormwater drainage channel or drain;
              Bore or a dam.

              Unsaturated soil depth to a permanent water table (vertically)                                       0.3 m                            0.6 m

            Note:     Distances measured from the edge of the irrigated wetted area to any point of the feature.


            Unsaturated soil depths of 0.6 m (i.e. depth to rock or wet soil) and 0.3 m are recommended for Secondary
            and Advanced Secondary effluent, respectively. Test pits indicate that such adequate unsaturated soil
            depths are available across the proposed effluent disposal area.
            The layout for effluent treatment and disposal on the new lot shall be decided at building stage, in
            conjunction with a design provided by a NC registered evaluator.




             22 May 2023
             Report No. 23099-001-Rev0                                                 21

Document Set ID: 22826802
Version: 1, Version Date: 23/02/2024