Phase I Desk Study Report Project: Dolphins, Eldon Road, Hoddesdon Client: KK Electrical Ltd Reference: M43579-JNP-XX-XX-RP-G-0001 P01 Date: March 2021 M43579-JNP-XX-XX-RP-G-0001 P01 Dolphins, Hoddesdon Phase I Desk Study Report DOCUMENT CONTROL SHEET Prepared by……………………………………… Sam Pyott BSc Graduate Geo-environmental Engineer Approved by……………………………. Hilary Ilsley BSc (Jnt Hons) MSc CBiol MSB SQP SiLC QP Associate Geo-environmental Scientist FOR AND ON BEHALF OF JNP GROUP Date: 9 March 2021 Document Issue Record Rev Date Description Prepared Checked Approved P01 9/3/21 First Issue SP HI HI This document is for the sole use and reliance of JNP Group ’s client and has been prepared in accordance with the scope of the appointment of JNP Group and is subject to the terms of that appointment. JNP Group accepts no liability for any use of this document other than by its client and only for the purposes for which it has been prepared. No person other than the client may copy (in whole or in part) or use the contents of this document, without the prior written permission of JNP Group . Any advice, opinions, or recommendations within this document should be read and relied upon only in the context of this document as a whole. The copyright at all times remains with JNP Group . 1 9 March 2021 M43579-JNP-XX-XX-RP-G-0001 P01 Dolphins, Hoddesdon Phase I Desk Study Report Contents INTRODUCTION .............................................................................................................. 4 GENERAL .......................................................................................................................... 4 OBJECTIVES ....................................................................................................................... 4 METHODOLOGY ................................................................................................................. 4 SITE DESCRIPTION .......................................................................................................... 5 GEOLOGY, HYDROGEOLOGY AND HYDROLOGY ............................................................... 6 GEOLOGY ......................................................................................................................... 6 BGS BOREHOLE RECORDS ................................................................................................... 6 RADON ............................................................................................................................ 7 BACKGROUND SOIL CHEMICAL CONCENTRATIONS ................................................................... 7 MINING , MINERAL EXTRACTION AND NATURAL CAVITIES ......................................................... 7 HYDROGEOLOGY ................................................................................................................ 8 HYDROLOGY ...................................................................................................................... 9 POLLUTION INCIDENTS TO CONTROLLED WATERS .................................................................... 9 DISCHARGE CONSENTS ....................................................................................................... 9 SITE HISTORY ............................................................................................................... 11 HISTORICAL MAPPING ...................................................................................................... 11 UNEXPLODED ORDNANCE REVIEW ...................................................................................... 12 SITE HISTORICAL SUMMARY ............................................................................................... 12 INFORMATION HELD BY STATUTORY AUTHORITIES ....................................................... 13 SUMMARY ...................................................................................................................... 13 ENVIRONMENTALLY SENSITIVE AREAS ................................................................................. 13 UK CONTAMINATED LAND LEGISLATIVE FRAMEWORK .................................................. 14 GENERAL ........................................................................................................................ 14 CONCEPTUAL SITE MODEL AND PRELIMINARY RISK ASSESSMENT.................................. 16 GENERAL ........................................................................................................................ 16 POTENTIAL SOURCES OF CONTAMINATION ........................................................................... 16 RECEPTORS ..................................................................................................................... 16 PATHWAYS ..................................................................................................................... 17 POLLUTANT LINKAGES ...................................................................................................... 18 PRELIMINARY RISK ASSESSMENT ......................................................................................... 20 CONCLUSIONS OF DESK STUDY & RECOMMENDATIONS ................................................ 21 CONCLUSIONS ................................................................................................................. 21 RECOMMENDATIONS ........................................................................................................ 21 REFERENCES ................................................................................................................. 22 FIGURES / DRAWINGS ................................................................................................................ 26 APPENDIX A: LIMITATIONS ......................................................................................................... 27 2 9 March 2021 M43579-JNP-XX-XX-RP-G-0001 P01 Dolphins, Hoddesdon Phase I Desk Study Report APPENDIX B PHOTOGRAPH DOCUMENT ..................................................................................... 31 APPENDIX C GROUNDSURE REPORT ............................................................................................ 32 APPENDIX D HISTORICAL MAPS .................................................................................................. 33 List of Tables Table 2-1 Surrounding Land Use .............................................................................................. 5 Table 3-1: Geological Hazards .................................................................................................. 6 Table 3-3 Summary of Discharge Consents ............................................................................. 9 Table 4-1: Site Historical Summary ........................................................................................ 11 Table 5-1 Statutory Information Summary ............................................................................ 13 Table 7-1: Risk Matrix ............................................................................................................ 15 Table 8-1: Potential Source-Pathway-Receptor Linkages for Human Health Risk Assessment ....................................................................................................................................... 18 Table 8-3: Source Pathway Receptor Linkages for Controlled Waters Risk Assessment ....... 19 Table 8-4: Potential Source-Pathway-Receptor Linkages for Property Risk Assessment ...... 19 Table 8-5: Potential Source-Pathway-Receptor Linkages for Ecological Risk Assessment .... 19 Table 8-6: Preliminary Risk Assessment ................................................................................ 20 List of Figures / Drawings Figure 1 Key Plan Proposed Re-Development MP Architects LLP drawing 2406-02-B. 3 9 March 2021 M43579-JNP-XX-XX-RP-G-0001 P01 Dolphins, Hoddesdon Phase I Desk Study Report INTRODUCTION General JNP Group was instructed by KK Electrical Ltd, hereinafter referred to as the client, to undertake a phase I desk study of: Dolphins, Eldon Road, Hoddesdon, Hertfordshire, EN11 0BD hereinafter referred to as ‘the site’. This report is subject to the limitations presented in Appendix A. It is understood that the site is to be redeveloped with a single large two-storey residential property with private gardens and parking. The proposed redevelopment layout is shown on MP Architects LLP drawing 2406-02-B dated October 2020. All comments given are based on the understanding that the proposed redevelopment will be as detailed above. Objectives The scope of work comprised non-intrusive (desk-based) research and a site walkover. This report contains details of the site, development of an initial conceptual model, and a preliminary risk assessment with regard to contaminated land issues. Methodology This report has been compiled in accordance with the on-line Land contamination: risk management (LCRM) guidance produced by the Environment Agency (June 2019). This can be found on the UK government website: https://www.gov.uk/guidance/land- contamination-how-to-manage-the-risks . With regard to geotechnical aspects, reference is also made to the requirements of BS EN 1997, Eurocode 7, Geotechnical Design, and associated standards. 4 9 March 2021 M43579-JNP-XX-XX-RP-G-0001 P01 Dolphins, Hoddesdon Phase I Desk Study Report SITE DESCRIPTION The site is located Eldon Road, in Hoddesdon, Hertfordshire, EN11 0BD approximately 1.7 km south-east of Hoddesdon town centre (see Figure 1 Key Plan). The centre