Chapter 4 Environmental Values and Management of Impacts Table of Contents 4. Environmental Values and Management of Impacts ................................................................................ 1 4.1 Introduction ................................................................................................................................... 1 4.1.1 Objectives ............................................................................................................................ 1 4.1.2 Project Description ............................................................................................................... 1 4.1.3 Legislative Overview ............................................................................................................ 4 4.1.4 Other Potentially Applicable National Plans or Policies ...................................................... 10 4.1.5 Project Standards and Guidelines ....................................................................................... 10 4.1.6 Impact Assessment Methodology ........................................................................................ 17 4.1.7 Cumulative Impact Assessment Methodology ..................................................................... 18 4.1.8 Chapter Overview .............................................................................................................. 19 4.2 Weather and Climate ................................................................................................................... 21 4.2.1 Methodology ...................................................................................................................... 21 4.2.2 Existing Environment .......................................................................................................... 25 4.3 Geology, Geohazards and Soils ................................................................................................... 31 4.3.1 Standards and Reference Values Applied ............................................................................ 31 4.3.2 Methodology ...................................................................................................................... 31 4.3.3 Existing Values ................................................................................................................... 34 4.3.4 Potential Impacts ................................................................................................................ 40 4.3.5 Impact Assessment ............................................................................................................. 44 4.3.6 Mitigation Measures ........................................................................................................... 48 4.4 Surface Water Quality and Flows ................................................................................................. 51 4.4.1 Standards Applied .............................................................................................................. 51 4.4.2 Methodology ...................................................................................................................... 51 4.4.3 Existing Values ................................................................................................................... 54 4.4.4 Potential Impacts ................................................................................................................ 55 4.4.5 Impact Assessment ............................................................................................................. 57 4.4.6 Mitigation Measures ........................................................................................................... 62 4.5 Groundwater ................................................................................................................................ 66 4.5.1 Standards Applied .............................................................................................................. 66 4.5.2 Methodology ...................................................................................................................... 67 4.5.3 Existing Values ................................................................................................................... 69 4.5.4 Potential Impacts ................................................................................................................ 73 4.5.5 Impact Assessment ............................................................................................................. 74 4.5.6 Mitigation Measures ........................................................................................................... 76 4.6 Community Water Supply ............................................................................................................ 77 4.6.1 Regulatory Agencies ........................................................................................................... 77 4.6.2 Standards Applied .............................................................................................................. 77 4.6.3 Methodology ...................................................................................................................... 78 4.6.4 Existing Values ................................................................................................................... 80 4.6.5 Potential Impacts ................................................................................................................ 83 4.6.6 Impact Assessment ............................................................................................................. 85 4.6.7 Mitigation Measures ........................................................................................................... 88 4.7 Freshwater Ecology ...................................................................................................................... 91 4.7.1 Standards Applied .............................................................................................................. 91 4.7.2 Methodology ...................................................................................................................... 91 4.7.3 Existing Values ................................................................................................................... 93 4.7.4 Potential Impacts ................................................................................................................ 99 4.7.5 Impact Assessment ........................................................................................................... 103 4.7.6 Mitigation Measures ......................................................................................................... 106 4.8 Marine Ecology .......................................................................................................................... 109 4.8.1 Standards Applied ............................................................................................................ 109 4.8.2 Methodology .................................................................................................................... 109 4.8.3 Existing Values ................................................................................................................. 112 4.8.4 Potential Impacts .............................................................................................................. 117 PAGE i 4.8.5 Impact Assessment ........................................................................................................... 124 4.8.6 Mitigation Measures ......................................................................................................... 129 4.9 Terrestrial Ecology ...................................................................................................................... 133 4.9.1 Methodology .................................................................................................................... 133 4.9.2 Existing Values ................................................................................................................. 136 4.9.3 Potential Impacts .............................................................................................................. 147 4.9.4 Impact Assessment ........................................................................................................... 150 4.9.5 Mitigation Measures ......................................................................................................... 155 4.10 Air Quality ................................................................................................................................. 158 4.10.1 Standards Applied ............................................................................................................ 158 4.10.2 Methodology .................................................................................................................... 159 4.10.3 Existing Values ................................................................................................................. 164 4.10.4 Potential Impacts .............................................................................................................. 164 4.10.5 Impact Assessment ........................................................................................................... 166 4.10.6 Mitigation Measures ........................................................................................................