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Environmental Risk Assessment Poyle Quarry Western Extension Land West of Colne Brook, Foundry Lane, Horton, Slough Environmental Risk Assessment On behalf of Summerleaze Ltd Project Ref: 35678/3505 | Rev: 01 | Date: October 2019 Registered Office: Buckingham Court Kingsmead Business Park, London Road, High Wycombe, Buckinghamshire, HP11 1JU Office Address: Caversham Bridge House, Waterman Place, Reading, Berkshire RG1 8DN T: +44 (0)118 950 0761 E: [email protected] Environmental Risk Assessment Poyle Quarry Western Extension Document Control Sheet Project Name: Poyle Quarry Western Extension Project Ref: 35678/3505 Report Title: Environmental Risk Assessment Doc Ref: 35678/EP/R4 Date: October 2019 Name Position Signature Date Prepared by: Nicholas Hills Engineer NH 16/10/2019 Reviewed by: Kate Riley Associate KR 16/10/2019 Approved by: Paul Jeffery Director PJ 16/10/2019 For and on behalf of Peter Brett Associates LLP Revision Date Description Prepared Reviewed Approved Rev01 10/19 Issue NH VKR PJ This report has been prepared by Peter Brett Associates LLP (‘PBA’) on behalf of its client to whom this report is addressed (‘Client’) in connection with the project described in this report and takes into account the Client's particular instructions and requirements. This report was prepared in accordance with the professional services appointment under which PBA was appointed by its Client. This report is not intended for and should not be relied on by any third party (i.e. parties other than the Client). PBA accepts no duty or responsibility (including in negligence) to any party other than the Client and disclaims all liability of any nature whatsoever to any such party in respect of this report. © Peter Brett Associates LLP 2019 J:\35678 - Poyle Quarry\geo\2019 EP Application\ERA\Environmental Risk Assessment Issue.docx ii Environmental Risk Assessment Poyle Quarry Western Extension Contents 1 Introduction ................................................................................................................................. 2 1.1 Report Context .............................................................................................................. 2 1.2 Other Reports ................................................................................................................ 2 1.3 Proposed Activity ........................................................................................................... 3 2 Site Setting ................................................................................................................................... 4 2.1 Site Details .................................................................................................................... 4 2.2 Topography ................................................................................................................... 4 2.3 Geology and Ground Conditions ................................................................................... 4 2.4 Hydrogeology & Hydrology ............................................................................................ 5 2.5 Historical Land Use ....................................................................................................... 6 2.6 Current Land Use .......................................................................................................... 7 2.7 Ecology .......................................................................................................................... 7 3 Risk Assessment ......................................................................................................................... 9 3.1 Potential Risks ............................................................................................................... 9 3.2 Potential Hazards .......................................................................................................... 9 3.3 Potential Receptors ..................................................................................................... 14 3.4 Potential Exposure Pathways ...................................................................................... 16 3.5 Risk Assessment ......................................................................................................... 17 4 Conclusions ................................................................................................................................. 1 5 References ................................................................................................................................... 2 Figures Figure ERA1: Site Location Plan Figure ERA2: Site Context and Surrounding Land Use Figure ERA3: Potential Receptors Tables Table 2.1 Summary of Superficial and Solid Geology ........................................................................ 4 Table 2.2 Nearby Landfill Sites ........................................................................................................... 6 Table 2.3 Summary of Off-Site Land Uses ......................................................................................... 7 Table 2.4 Nearby Ecological Features ................................................................................................ 8 Table 3.1 Reports related to the Water Environment ....................................................................... 12 Table 3.2 Potential Receptors ........................................................................................................... 14 Table 3.2 Potential Exposure Pathways ........................................................................................... 16 Table 3.3 Risk Assessment................................................................................................................. 1 Appendices Appendix 1 Approved Plans J:\35678 - Poyle Quarry\geo\2019 EP Application\ERA\Environmental Risk Assessment Issue.docx 1 Environmental Risk Assessment Poyle Quarry Western Extension 1 Introduction 1.1 Report Context 1.1.1 This Environmental Risk Assessment (ERA) has been prepared by Peter Brett Associates - now part of Stantec (PBA) for a site in Poyle, near Slough, Berkshire (the Site), known as Poyle Quarry Western Extension The report has been prepared on behalf of Summerleaze Ltd, in support of an Environmental Permit (EP) application for an inert waste landfill following extraction of sand and gravel from the Site. The location of the Site is shown on Figure ERA1. 1.1.2 The report responds to Question 4 and Appendix 4 of Part B4 of the EP application forms (version 10, April 2018), which require the provision of an Environmental Risk Assessment (ERA) report to support the EP application and also to pre-application correspondence (EA/EPR/HB3409MJ/A001) with the Environment Agency (EA), copies of which are provided in Appendix A of the ESSD. 1.1.3 This section of the Environmental Permit (EP) application responds to pre-application correspondence (EA/EPR/HB3409MJ/A001) with the Environment Agency (EA), Question 4 and Appendix 4 of Part B4 of the EP application forms (version 10, April 2018), which require the provision of an ERA (this report) to support the EP application. 1.1.4 This ERA is informed by UK Government Guidance “ Risk assessments for your environmental permit ”1. 1.2 Other Reports 1.2.1 This ERA should be read in conjunction with the accompanying and supporting assessments and documents; ° Operating Techniques and Closure Plan (Ref 35678/EP/R2) 2 ° Environmental Setting and Site Design (ESSD) (Ref 35678/EP/R3) 3 ° Hydrogeological Risk Assessment (HRA) (Ref 35678/EP/R5)4 ° Groundwater, Surface Water and Landfill Gas Monitoring Plan (35678/EP/R6) 5 ° Flood Risk Assessment (Ref 35678/4001/02 Rev B)6 ° Groundwater Control and Mitigation Report (Ref 35678/3501)7 ° Recommencement of Mineral Processing, Construction of New Access Road, Transport of As-Raised and Processed Sand and Gravel and Importation of Infill Materials at Poyle Quarry, Poyle Road, Colnebrook, Berkshire. Vibrock. (Air Quality Assessment) (Ref R17.9662/2/SE)8 ° Dust Management Plan 9 ° Noise Assessment Report, WBM Acoustic Consultants, August 2017 (Ref 4684)10 ° Potential Noise Impact of Proposed Scheme on Additional Receptors off Foundry Lane, WBM Acoustic Consultants, April 2018 (Ref 4684)11 J:\35678 - Poyle Quarry\geo\2019 EP Application\ERA\Environmental Risk Assessment Issue.docx 2 Environmental Risk Assessment Poyle Quarry Western Extension 1.3 Proposed Activity 1.3.1 As described in the ESSD 3 the EP application is for an inert landfill, following quarry operations to extract mineral sand and gravel. A planning application for extraction of mineral at the Site was submitted to the Royal Borough of Windsor and Maidenhead on 3 rd November 2017 and subsequently permission was granted on the 28 th January 2019, providing planning consent for; ‘Sand and gravel extraction and restoration by infilling with inert waste of Poyle Quarry extension (preferred Area 12) ’ 1.3.2 Whilst the Site has not previously been subject to historical mineral extraction or infilling, it is located in an area which has been subject to significant historical mineral excavation and landfilling. Historical and current landfill locations are presented on Figure 2 and include the Horton Brook Quarry and inert landfill located adjacent to the western boundary of the Site. J:\35678 - Poyle Quarry\geo\2019 EP Application\ERA\Environmental Risk Assessment Issue.docx 3 Environmental Risk Assessment Poyle Quarry Western Extension 2 Site Setting 2.1 Site Details 2.1.1 The location of
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