Environmental Assessment Report
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M27 Southampton Junctions improvement scheme Environmental Assessment Report 2018 Environmental Assessment Report for M27 Southampton Junctions 1. Summary This EAR has been undertaken to assess the impacts of the scheme on environmental topics. Due to the stage of works, PCF Stage 2, all technical topics have been considered in the assessment. The assessment has predicted that with the exception landscape and potentially cultural heritage, neither Appraisal Option 1 nor 2 would result in ‘significant’ environmental effects. The ‘significant’ effects associated with landscape are limited to individual views and are as a result of the removal vegetation and the gas holders on the gas works site. The potential ‘significant’ effect associated with cultural heritage is to unknown undisturbed below-ground archaeological remains. The value of these assets (if present) is unknown therefore taking a worst-case scenario the effect pre- mitigation is assumed to be ‘moderate/large’ adverse. However, through undertaking of a detailed desk based assessment and if required intrusive investigations, any impacts to this heritage asset can likely be mitigated and resultant impacts thus might be considered likely to not be significant. (Requirement for intrusive investigations will depend upon the extent of physical works). Noise modelling has been undertaken, this has identified temporary adverse effects from noise and vibration are likely to occur during construction works associated with both Appraisal Option 1 and 2. However, it is recognised that the magnitude of the impact of the identified adverse effects should be reduced through the implementation of a Construction Environmental Management Plan (CEMP) in accordance with best practice measures. The redistribution of the traffic on the network as a result of Appraisal Option 1 will result in the A3024 corridor being expected to manage greater amounts of traffic. For Appraisal Option 1 there is a much great number of Heavy Goods Vehicles (HGVs) predicted to use the route due to the removal of the current weight restriction on Northam Road Rail Bridge. The resultant effect is that Appraisal Option 1 is predicted to result in a permanent significant adverse effect on some residential areas along the A3024 (most of the receptors impacted are outside of the Scheme boundary). Overall it is concluded that the impacts of Appraisal Option 2 are, due to the reduced scope of works, predicted to affect less receptors than Appraisal Option 1. 1 P08 February 2018 Environmental Assessment Report for M27 Southampton Junctions Table of contents Contents 1. Summary 1 Table of contents 2 2. Part 1: Introduction 9 2.1 Overview of the project report 9 2.1.1 Identify the scheme and stage of scheme 9 2.2 Overview of the project 9 2.2.1 Location of Scheme 9 2.3 Legislative and policy framework 10 2.4 Scope and content 11 2.4.1 Appraisal Option 1 11 2.4.2 Appraisal Option 2 12 2.5 Structure of the Report 12 3. Part 2: The Project 14 3.1 Need for the project 14 3.1.1 Background to the project 14 3.1.2 The proposed Works 14 3.2 Project objectives 15 3.3 Project location 15 3.3.1 Sub-scheme 1 15 3.3.2 Sub-scheme 2 16 3.3.3 Sub-scheme 3 16 3.3.4 Sub-scheme 5 17 3.4 Construction, operation and long-term management 17 4. Part 3: Assessment of Alternatives 18 4.1 Assessment methodology 18 4.1.1 Design Options Examined in PCF Stage 0 18 4.1.2 Design Options Examined in PCF Stage 1 18 4.2 Reasonable alternatives studied 20 4.2.1 Scenario Options for Consideration in Environmental Assessment 20 5. Part 4: Environmental assessment methodology 24 5.1 Environmental scoping 24 5.1.1 General Approach 24 5.1.2 Baseline Traffic flows 24 5.1.3 Scoping 24 5.2 General assumptions and limitations 26 5.3 Significance criteria 26 5.3.1 Mitigation enhancement 31 6. Air Quality 32 6.1 Legislative and policy framework 32 2 P08 February 2018 Environmental Assessment Report for M27 Southampton Junctions 6.1.1 National Legislation 32 6.1.2 Local Planning Policy 33 6.2 Study area 34 6.3 Baseline conditions (including value/sensitivity of resources and receptors) 35 6.3.1 Introduction 35 6.3.2 Air Quality Management Areas (AQMAs) 35 6.3.3 Local Authority Monitoring Data 38 6.3.4 Scheme Specific Monitoring Data 45 6.3.5 Ecological Receptors 47 6.3.6 Background mapped concentrations 48 6.4 Potential impacts 51 6.5 Assessment methodology 51 6.5.1 General Approach 51 6.5.2 Assessment Methodologies 52 6.5.3 Construction assessment 52 6.5.4 Operational assessment 53 6.5.5 Assessment Scenarios 53 6.5.6 Receptors 54 6.5.7 Background pollutant concentrations 54 6.5.8 NOx to NO2 54 6.5.9 Long Term Trends (Gap Analysis) 54 6.5.10 Regional Assessment 55 6.5.11 Ecological Assessment 55 6.5.12 Determining Significance of Effect 55 6.5.13 Compliance Risk Assessment 57 6.6 Assumptions and limitations of assessment 58 6.6.1 Construction assessment 58 6.6.2 Operational phase assessment 58 6.7 Design, mitigation and enhancement measures, including monitoring requirements 58 6.7.1 Mitigation 59 6.8 Assessment of effects 59 6.8.1 Construction – Local Air Quality 59 6.8.2 Operational – Local Air Quality 62 6.8.3 Magnitude of Impacts – Appraisal Option 1 65 6.8.4 Magnitude of Impacts – Appraisal Option 2 79 6.8.5 Significance of Effects 82 6.8.6 Cumulative Effects 82 6.8.7 Operational – Regional Air Quality 82 6.8.9 Ecological Assessment 84 6.8.10 Compliance Risk Assessment 88 6.8.11 Summary of Key Effects 90 6.9 References 91 7. Cultural Heritage 93 7.1 Legislative and policy framework 93 7.1.1 Legislation 93 7.1.2 National Policy 93 7.1.3 National Policy Statement for National Networks 93 7.1.4 National Planning Policy Framework 94 7.1.5 Local Policy 94 3 P08 February 2018 Environmental Assessment Report for M27 Southampton Junctions 7.2 Study area 95 7.3 Baseline conditions (including value/sensitivity of resources and receptors) 95 7.3.1 Sub Scheme 1 96 7.3.2 Sub Scheme 2 97 7.3.3 Sub scheme 3 – Northam Road Rail Bridge Replacement 102 7.3.4 Sub Scheme 5 106 7.4 Potential impacts 109 7.5 Assessment methodology 109 7.5.1 Terminology 109 7.5.2 Standards and guidance 109 7.5.3 Sensitivity or importance of the asset 110 7.6 Assessment assumptions and limitations 111 7.7 Design, mitigation and enhancement measures 111 7.8 Assessment of effects 112 7.8.1 Appraisal Option 1 112 7.8.2 Appraisal Option 2 117 8. Landscape, Townscape and Visual Assessment 118 8.1 Legislative and policy framework 118 8.1.1 National legislation and policy 118 8.1.2 Local Policy 119 8.2 Study area 120 8.3 Baseline conditions (including value/sensitivity of resources and receptors) 120 8.3.1 Landscape Designations within the study area 120 8.3.2 Landscape Character 122 8.3.3 Visual Amenity 124 8.4 Potential impacts 134 8.5 Assessment methodology 135 8.6 Assessment assumptions and limitations 137 8.7 Design, mitigation and enhancement measures 137 8.8 Assessment of effects 139 8.8.1 Appraisal Option 1 139 8.8.2 Appraisal Option 2 142 9. Biodiversity 145 9.1 Legislative and policy framework 145 9.1.1 National Legislation and Policy 145 9.1.2 Local Policy 145 9.2 Study area 146 9.3 Baseline conditions (including value/sensitivity of resources and receptors) 146 9.3.1 Statutory Designated Sites 146 9.3.2 Non- Statutory Designated Sites 149 9.3.3 Protected and notable species 151 9.3.4 Habitats of Principal Importance 152 9.3.5 Phase 1 Habitat Survey 2016 152 9.3.6 Ecological Walkover Survey 2017 152 9.3.7 Ecological Value 153 9.3.8 Potential Protected and Notable Species 153 9.4 Potential impacts 154 4 P08 February 2018 Environmental Assessment Report for M27 Southampton Junctions 9.5 Assessment methodology 157 9.6 Assessment assumptions and limitations 157 9.7 Design, mitigation and enhancement measures 159 9.7.1 Design and Embedded Mitigation 159 9.7.2 Monitoring and Management Post Construction 161 9.8 Assessment of effects 161 9.8.1 Appraisal Options 1 and 2 161 10. Geology and Soils 165 10.1 Legislative and policy framework 165 10.2 Study area 166 10.3 Baseline conditions (including value/sensitivity of resources and receptors) 166 10.3.1 Ground Conditions 166 10.3.2 Designated sites 167 10.3.3 Soils 167 10.3.4 Groundwater 167 10.3.5 Surface water 168 10.3.6 Historical land use 168 10.3.7 Current land use 169 10.3.8 Potential for land contamination 169 10.3.9 Conceptual site model 171 10.3.10 Attribute Importance (Sensitivity) 174 10.4 Potential impacts 176 10.4.1 Sub-scheme 1: 176 10.4.2 Sub-scheme 2 176 10.4.3 Sub-scheme 3: 176 10.4.4 Sub-scheme 5 176 10.5 Assessment methodology 177 10.6 Assessment assumptions and limitations 184 10.7 Design, mitigation and enhancement measures 184 10.8 Assessment of effects 185 10.8.1 Appraisal Option 1 185 10.8.2 Appraisal Option 2 186 11. Materials 187 11.1 Legislative and policy framework 187 11.2 Study area 190 11.3 Baseline conditions (including value/sensitivity of resources and receptors) 190 11.3.1 Materials and waste generated 190 11.3.2 Materials 191 11.4 Potential impacts 194 11.5 Assessment methodology 195 11.6 Assessment assumptions and limitations 196 11.7 Design, mitigation and enhancement measures 196 11.8 Assessment of effects 197 11.8.1 Appraisal Option 1 197 11.8.2 Appraisal Option 2 199 12.