Reference Documents - RAL22/0032

                Contour Consulting Engineers                                                                    23038-001-Rev0
                                                                                                                  6 March 2023

                4.2.3 Filling
                Site soils where free of deleterious materials (e.g. vegetation, oversize etc.) are expected to be suitable for
                re-use as structural fill, subject to appropriate moisture adjustment. It should be noted that compaction of
                highly reactive clays, as are anticipated at this site, could be difficult during wet weather and adverse impacts
                on site classification for footing and pavement design should be considered when re-using such clays.
                Should importation of fill be required, it is recommended that such fill should comply with the following:

                          Minimum CBR of 10%
                          Maximum plasticity index of 15%
                          Shrink-swell index ≤ 1%
                          Maximum particle size of 100 mm

                Controlled fill materials should be compacted at moisture contents within the range of -2% to +2% of OMC for
                Standard Compaction. Confirmatory testing must be carried out at regular intervals and further details for
                control and testing of fill are given in Australian Standard AS 3798-2007 Guidelines on Earthworks for
                Commercial and Residential Developments. Select fill should have a maximum particle size of 100 mm for
                an uncompacted layer thickness of 200 mm and shall be compacted by repeated rolling with a small
                compactor to achieve a dry density ratio of at least 95% of the Standard Maximum Dry Density for cohesive
                soils, or 70% Dry Density Index for any imported cohesionless soils.
                Fill must be ‘benched’ into the natural soil, over-filled by 0.5 m (horizontally) and then trimmed back to the
                well compacted material.

                4.3       Drainage
                During construction, temporary open swales and diversion drainage may be required to divert seepage
                and/or runoff away from the construction area.

                Permanent drainage must be installed to ensure that stormwater runoff from the driveway is formally
                collected (e.g. positive gradients along the pavement directing stormwater into side drains). As the driveway
                alignment runs down a natural slope, it would be prudent to include surface water flow dissipation devices
                such as ‘water bars’ and/or rock check dams at regular intervals to reduce runoff velocity and minimise
                erosion.

                All stormwater collected from the driveway should be directed by pipes or surface channels to discharge into
                the existing stormwater infrastructure along Uhlmanns Road. Surface protection along channels should be
                assessed by the design engineer on a case-by-case basis depending on the specific conditions and may
                range from turf in low velocity flow areas to rock or concrete in high velocity flow zones. A surface
                dissipation device such as rock weir must be installed at the stormwater outlet(s), where not discharging into
                an existing pit.

                Subsurface disposal of stormwater must not be undertaken (including infiltration pits).




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Document Set ID: 22374434
Version: 1, Version Date: 14/04/2023