PG-9236, 2022-10-31, Asr Ver 1

Project No. PG-9236                                                                                                                Page | 1
November 2022
Ref: PG-9236, 2022-11-01, ASSMP VER 1
Looroo Property Trust – Acid Sulfate Soil Management Plan – Proposed Residential Development, 128-132 Gympie Terrace, Noosaville




                         Acid Sulfate Soil Management Plan (ASSMP)
                           PROPOSED RESIDENTIAL DEVELOPMENT
                           128-132 GYMPIE TERRACE, NOOSAVILLE

Objective                              The objective of the ASSMP is to control any acid generation from
                                       insitu ASS materials and to restrict to an acceptable level any
                                       potential on-site and off-site environmental impacts. A further
                                       objective is to manage earthworks activities and provide measures
                                       to maintain water quality within the site and in adjacent areas.
Proposed                               It is understood that the proposed development is to comprise the
Development                            construction of a two storey residences above a single storey
                                       basement. Earthworks are envisaged to consist of cuts of up to 3m
                                       for the basement. A total volume of material to be disturbed is less
                                       than 3,000m3.
Subsurface Conditions                  Mapping
                                       The site is located in an area that is mapped on the Queensland
                                       Department of Natural Resources and Mines Acid Sulfate Soils
                                       Tweed Heads to Redcliffe sheet as Disturbed Land likely to contain
                                       ASS.
                                       ASS Investigation
                                       Drilling and sampling encountered a reasonably consistent profile of
                                       sand that:
                                       • did not indicate any obvious ASS presence from a visual and
                                             tactile perspective in the fill or the natural profile.
                                       •     indicated that the upper level sands were not acid sulfate soils
                                             and the sands between 1.5m and 2.5m indicated a low level of
                                             acid sulfate soil present.
                                       •     had the highest liming rate required to neutralise the acidity of
                                             8kg/m3 (based on laboratory testing of selected samples). For
                                             the lower level silty sands.
                                       •     The proposed excavations (to 3m) will disturb the acid sulfate
                                             soils.
                                       •     Given the proposed excavation levels, disturbance of acid
                                             sulfate soils will occur and treatment for acid sulfate will be
                                             required for materials distributed greater than 1.5m below
                                             ground level.
Management                             To mitigate and manage potential adverse environmental impacts
Strategy                               during site construction operations, the following will be undertaken:
                                       • an ASS consultant should review the site earthworks schedule
                                           and plan of operations;
                                       •     adoption of appropriate erosion control measures to limit
                                             sediment loss due to run-off from site works area;
                                       •     where excavation below the water table, or if disturbance of
                                             any silty sands is necessary, a materials handling and
                                             management strategy and procedures for lime treatment of any
                                             disturbed material will be required;
                                       •     monitoring and treatment (if necessary) of waters in detention
                                             basins to a level suitable for discharge into external waterways;
                                             and
                                       •     site supervision by approved persons and regular reporting to
                                             the Project Engineer/Manager throughout the construction
                                             phase.