REFERENCE DOCUMENTS - RAL25/0004 (As Published)

                      3.2   Identify the information needed to establish      Guideline criteria established by this Report.
                            the action level.
                      3.3   Confirm that appropriate sampling and             Sampling and analytical methods will be
                            analytical methods exist to provide the           consistent with existing guidance including
                            necessary data.                                   NEPM.
                                                                              Analytical laboratories are NATA accredited.
                      4     Define the boundaries of the study – define the target population, the spatial and temporal
                            boundaries associated with the population, examine any practical constraints to collecting data,
                            and factors that affect the selection of the unit which defines the scale of sampling and the scale
                            of decision making or estimation.
                      4.1   Define the target population(s) of interest       Refer to the CSM and Drawings presented in
                            and its relevant spatial boundaries.              Appendix A.
                      4.2   Define what constitutes a sampling unit.          Soil sampling units including fill, natural or
                                                                              topsoil samples, as well as sampling units for
                                                                              surface and groundwater, soil vapour or landfill
                                                                              gas.
                      4.3   Specify temporal boundaries and other             Temporal boundary is the time in which the DSI
                            practical constraints associated with             was conducted (over two main efforts with the
                            sample/data collection.                           second iterative stage involving LFG and
                                                                              various impact delineation works).

                                                                              The practical constraints to sample/data
                                                                              collection include limited reach of the sampling
                                                                              methods (approximately 3mbgl for the
                                                                              excavator, with drill rig limitations based on
                                                                              encountered wastes and geology and maximum
                                                                              design drill depths of the rig - required to be at
                                                                              least >25m for groundwater bore installation and
                                                                              >3m for LFG bores). Other site access
                                                                              obstructions are predominately trees and other
                                                                              dense vegetation as well as the shed footprint.
                      4.4   Specify the smallest unit on which decisions      The Limit of Reporting (LOR) of laboratory
                            or estimates will be made.                        analysis combined with visual observations of
                                                                              test pits.
                      5     Develop the analytic (statistical) approach – develop a logical “if …, then …, or …” statement
                            that defines the conditions that would cause the decision maker to choose among alternative
                            actions.
                      5.1   Specify the statistical parameter that            The 95% UCL of the arithmetic average will be
                            characterises the population of interest, such    another key statistical parameter to evaluate the
                            as mean, median, maximum, 95% upper               significance of the laboratory data for a relevant
                            confidence limit (UCL) of the arithmetic          soil population against assessment criteria:
                            average, proportion.                              •   no sample to exceed 250% of the criteria
                                                                              •   standard deviation to be <50% criteria
                                                                              •   95% UCL is < criteria.
                      5.2   Specify the action level for the decision.        Criteria for relevant media as presented in
                                                                              Section 7 of this Report.




        125 Lot 105 SP118458 Cooroy DSI 12062024 Rev0                                                 Lot 105 SP118458, Cooroy, QLD, 4563
        12/06/2024                                                       34                        Detailed Site Contamination Investigation
Document Set ID: 23717062
Version: 0, Version Date: 01/01/1900