AIRpoRT AND SURROUNds GEOLOGY, SOILS AND GROUNDWATER B3 CONTENTS 3.3.4 Erosion and sediment control ............................... 34 3.3.5 Land resources assessment .................................. 34 3.1 Introduction ......................................................................... 21 3.3.6 Groundwater ................................................................ 35 3.1.1 Site description ............................................................21 3.4 Policy context and legislative framework .................35 3.1.2 Study area ......................................................................21 3.4.1 Geotechnical ................................................................ 35 3.3.2 Proposed development ............................................21 3.4.2 Acid sulphate soil ....................................................... 35 3.2 Methodology ....................................................................... 21 3.4.3 Contaminated land .................................................... 35 3.2.1 Geotechnical conditions ..........................................21 3.4.4 Erosion and sediment control ............................... 36 3.2.1.1 Desktop review .............................................21 3.4.5 Land resource assessment .................................... 36 3.2.1.2 Field investigation ....................................... 25 3.4.6 Groundwater ................................................................ 36 3.2.1.3 Laboratory testing ...................................... 25 3.5 Existing conditions ........................................................... 37 3.2.2 Acid sulphate soil ....................................................... 25 3.5.1 Geotechnical conditions ..........................................37 3.2.2.1 Desktop review .............................................27 3.5.1.1 Overview ..........................................................37 3.2.2.2 Field investigation ........................................27 3.5.1.2 Detailed description ...................................37 3.2.2.3 Laboratory testing .......................................27 3.5.2 Acid sulphate soil ........................................................41 3.2.3 Contaminated land .................................................... 28 3.5.2.1 Overview ..........................................................41 3.2.3.1 Desktop review ............................................ 28 3.5.2.2 Desktop assessment .................................41 3.2.3.2 Field investigation ....................................... 28 3.5.2.3 Preliminary screening ............................... 46 3.2.4 Erosion and sediment control ............................... 28 3.5.2.4 Quantitative soil analysis ......................... 46 3.2.4.1 Field investigation ....................................... 29 3.5.3 Contaminated land .....................................................47 3.2.4.2 Laboratory testing ...................................... 29 3.5.3.1 Site history ..................................................... 48 3.2.4.3 Assessment of soil erosion and 3.5.3.2 Potential areas of concern ..................... 50 dispersion potential ................................... 29 3.5.3.3 Contamination investigation .................. 50 3.2.5 Land resource assessment .................................... 30 3.5.4 Erosion and sediment control ............................... 50 3.2.5.1 Desktop review ............................................ 30 3.5.4.1 Site conditions ............................................. 50 3.2.5.2 Field investigation ....................................... 30 3.5.4.2 Laboratory testing ...................................... 53 3.2.6 Groundwater .................................................................31 3.5.4.3 Hydrology and rainfall erosivity ............ 53 3.2.6.1 Desktop review ............................................ 32 3.5.4.4 Seasonal weather patterns .................... 55 3.2.6.2 Field investigation ....................................... 32 3.5.4.5 Predicted erosion potential .................... 55 3.3 Assumptions and limitations .........................................33 3.5.5 Land resource assessment .....................................57 3.3.1 Geotechnical ................................................................ 33 3.5.5.1 Field investigation ........................................57 3.3.2 Acid sulphate soil ....................................................... 33 3.5.5.2 SCL assessment ........................................ 63 3.3.3 Contaminated land .................................................... 34 3.5.5.3 GQAL suitability .......................................... 63 B3-18 SUNSHINE COAST AIRPORT EXPANSION PROJECT 3.5.6 Groundwater ................................................................ 66 FIGURES 3.5.6.1 Topography and drainage ...................... 66 3.5.6.2 Climate ............................................................ 66 3.1a: Location of the Sunshine Coast Airport ........................ 22 3.5.6.3 Nearby groundwater bores .................... 66 3.1b: Surrounding land uses ........................................................... 23 3.5.6.4 Groundwater and surface 3.1c: Geotechnical, soils and groundwater study area ...... 23 water monitoring ......................................... 66 3.1d: Proposed development ......................................................... 24 3.5.6.5 Field testing ....................................................67 3.2a: Field investigation locations ................................................. 26 3.6 Assessment of potential impacts and 3.5a: Inferred very soft to soft clay thickness contours mitigation measures ........................................................ 73 and proposed preload area ................................................. 40 3.6.1 Description of impact assessment criteria ...... 73 3.5b: Extract of NRM&E ASS mapping for the Project ...... 42 3.6.2 Items requiring risk evaluation .............................. 73 3.5c: ASS sampling locations ........................................................ 43 3.6.2.1 Item 1 – Geotechnical ..............................73 3.5d: Inferred subsurface cross section for ASS – length of runway ....................................................................... 44 3.6.2.2 Item 2 – Acid sulphate soils ..................73 3.5e: Inferred subsurface cross section for ASS – 3.6.2.3 Item 3 – Soil contamination ...................74 crossing runway ........................................................................ 45 3.6.2.4 Item 4 – Erosion hazard ..........................74 3.5f: Contaminated land investigation areas of 3.6.2.5 Item 5 – Land resource ...........................75 concern and borehole locations .........................................51 3.6.2.6 Item 6 – Groundwater ..............................75 3.5g: Annual rainfall from 1994 to 2013 at 3.7 Description of impact ...................................................... 75 Sunshine Coast Airport ......................................................... 55 3.7.1 Geotechnical ................................................................ 75 3.5h: Extract from Land Resource Area, from Horticulture Land Suitability Study, 3.7.1.1 Consolidation ................................................75 Sunshine Coast, South East Queensland ..................... 58 3.7.1.2 Embankment stability ................................75 3.5i: Extract from Horticulture Land Suitability Study, 3.7.2 Acid sulphate soils ..................................................... 76 Sunshine Coast, South East Queensland ..................... 59 3.7.3 Contaminated land .................................................... 76 3.5j: Conceptual hydrogeological model ................................. 68 3.7.4 Erosion and sediment control ............................... 76 3.5k: Conceptual diagram showing variation in 3.7.4.1 Predicted erosion potential .....................76 depth to groundwater across the site ............................. 69 3.7.4.2 Soil dispersion potential ...........................76 3.5l: Groundwater depth at deep well BH9-13 and 3.7.5 Land resource assessment impacts .................. 77 recorded rainfaill ........................................................................72 3.7.5.1 Strategic cropping land impacts ......... 77 3.5m: Groundwater depth at shallow well BH1-13 and recorded tide heights .....................................................72 3.7.5.2 Good quality agricultural land impacts ................................................................ 77 3.5n: Groundwater depth at shallow well BH1-13 and recorded rainfaill ...............................................................72 3.7.6 Groundwater ................................................................ 77 3.7a: Hydrogeological conceptualisation of tailwater 3.7.6.1 Potential impacts from reclamation ... 77 infiltration with no mitigation ................................................78 3.7.6.2 Potential impacts from the 3.7b: Hydrogeological conceptualisation of tailwater northern perimeter drain ..........................79 infiltration with a high quality liner indicating 3.7.7 Mitigation ....................................................................... 83 reduced infiltration ....................................................................78 3.7.7.1 ASS mitigation measures 3.7c: Contours for predicted 0.1 m increase in and recommendations ............................