Gorpley Wind Farm Chapter 8 Environmental Statement Geology, Hydrology and Hydrogeology 8 GEOLOGY, HYDROLOGY AND HYDROGEOLOGY 8.1 INTRODUCTION This Chapter of the Environmental Statement (ES) assesses the hydrological and hydrogeological effects of the Development during construction, operation and decommissioning. Reference is made to Chapter 6: Ecology of this ES where appropriate. This Chapter contains the following sections: • Assessment Methodology and Significance Criteria – a description of the methods used in baseline surveys and in the assessment of the significance of effects; • Baseline Description - a description of the hydrology and hydrogeology of the Development based on the results of surveys, desk information and consultations, and a summary of any information required for the assessment that could not be obtained; • Assessment of Potential Effects - identifying the ways in which hydrological and hydrogeological resources could be affected by the Development, including a summary of the measures taken during design of the Development to minimise hydrological and hydrogeological effects; • Mitigation measures - a description of measures recommended to off-set potential negative effects; • Residual effects - a summary of the significance of the effects of the Development, after mitigation measures have been implemented; • Cumulative effects – identifying the potential for effects of the Development to combine with those from other developments to affect hydrological and hydrogeological resources; and • Statement of Significance. This Chapter is supported by the following Figures (Volume II: Figures of this ES) and Technical Appendices (Volume III: Technical Appendices of this ES): • Figure 8.1, Surface Watercourses and Catchments; • Figure 8.2, Solid Geology; • Figure 8.3, Superficial Geology; • Technical Appendix A8.1, Flood Risk Assessment; • Technical Appendix A8.2, Draft Water, Construction and Environmental Management Plan (WCEMP); and • Technical Appendix A8.3, Peat Slide Risk Assessment (SLR Consulting Ltd). 8.2 ASSESSMENT METHODOLOGY AND SIGNIFICANCE CRITERIA 8.2.1 Assessment Methodology This assessment has involved the following elements, further details of which are provided in the following sections: • Consultation with relevant statutory and non-statutory bodies; • Desk study, including review of available maps and published information; • Site walkover; • Evaluation of potential effects; • Evaluation of the significance of these effects; and • Identification of measures to avoid and mitigate potential effects. 8.2.2 Guidance The assessment has been undertaken in line with the following policy and guidance: Kelda Water Services Arcus Renewable Energy Consulting Ltd October 2012 Page 8-1 Chapter 8 Gorpley Wind Farm Geology, Hydrology and Hydrogeology Environmental Statement • Water Framework Directive (2000/60/EC)1. The Water Framework Directive (WFD) establishes a framework for the protection, improvement and sustainable use of all water environments; • National Planning Policy Framework (NPPF), paragraphs 100 to 1082. This states that for development comprising one hectare or above, the vulnerability to flooding, or the potential to add to flooding elsewhere should be assessed in a Flood Risk Assessment (FRA); • ‘Investigating the impacts of wind farm development on peatlands in England (NECR032)’ (2010)3. Natural England commissioned this study to develop a set of assessment criteria against which a development proposal can be tested to determine the scale of impact and enable an appropriate response to the EIA. • The Scottish Government Guidance: ‘Peat Landslide Hazard and Risk Assessments – Best Practice Guide for Proposed Electricity Generation Developments’ (2006). There is no relevant English guidance for peat survey, assessment or wind farm development on peat lands. Scottish guidance is not necessarily required in England, however it represents a tried and tested methodology for assessing peat slide risk; • The Construction Industry Research and Information Association (CIRIA) Environmental Good Practice on Site (C692) (2010)4. C692 provides guidance on how to avoid causing environmental damage when on a construction site; and • CIRIA Control of Water Pollution from Construction Sites (C532) (2001)5. C532 provides guidance on how to plan and manage construction projects to control water pollution. 8.2.3 Consultation Information has been provided by a range of organisations during the assessment, and this is summarised in Table 8.1. Table 8.1 Consultation Responses Consultee Key Points in Response Action Taken National River Flow Information provided on meteorological The information was used to Archive conditions and regional climatic averages. inform this assessment. Environment Agency Provided information relating flooding (EA) records. Scoping response: • As the site area is over 1 hectare (ha) A Flood Risk Assessment in size any planning application for this (FRA) is provided as development will require a Flood Risk Technical Appendix A8.1. Assessment (FRA). • The prior written consent of the No turbines are within 8 m of Environment Agency is required for any watercourses or hydrological proposed works or structures in, under, resources. over or within 8 metres of the top of the bank of a 'Main River', or within 8 metres of any flood defence. 1 European Parliament (2000). “Directive 2000/60/EC of the European Parliament and of the Council establishing a framework for the Community action in the field of water policy” (“The Water Framework Directive”). [online] Available at: http://ec.europa.eu/environment/water/water-framework/index_en.html [Accessed 11/09/2012]. 2 Department for Communities and Local Government (DCLG) (2012). “National Planning Policy Framework - 10. Meeting the challenge of climate change, flooding and coastal change” [online] Available at: http://www.communities.gov.uk/documents/planningandbuilding/pdf/2116950.pdf [Accessed 04/04/2012]. 3 Natural England Investigating the impacts of windfarm development on peatlands in England (NECR032)’ (2010) [online] Available at: http://publications.naturalengland.org.uk/publication/43010 [Accessed 10/10/2012]. 4 CIRIA (2010). “Environmental Good Practice On Site”. C692. [online] Available at: http://www.ciria.org/acatalog/c650.pdf [Accessed 11/06/2012]. 5 CIRIA (2001). “Control of Water Pollution from Construction Sites”. [online] Available at: http://www.ciria.org [Accessed 11/06/2012]. Arcus Renewable Energy Consulting Ltd Kelda Water Services Page 8-2 October 2012 Gorpley Wind Farm Chapter 8 Environmental Statement Geology, Hydrology and Hydrogeology Consultee Key Points in Response Action Taken • There should be no increase in surface SuDS measures, proposed as water runoff from the new part of the FRA, will ensure development. that surface water run-off will be managed. Yorkshire Water Provided information on waters supply The information was used to pipes on the Development site and inform this assessment. requested a 3 m stand-off from such pipes. Natural England The ES should thoroughly assess the RIGS data was requested impact of the proposals on non-statutory from the West Yorkshire sites, for example Local Wildlife Sites Geology Trust. The (LoWS), Local Nature Reserves (LNR) and information was used to Regionally Important Geological and inform this assessment. Geomorphological Sites (RIGS). Calderdale We would ask that within the EIA that Private water supplies are Metropolitan Borough risks of impact to private water supplies in considered within Section 8.4 Council (CMBC) Calderdale are fully assessed. of this Chapter. Provided information on private water The information was used to supplies. inform this assessment. The British Geological Provided details on solid and drift geology, The information was used to Survey borehole logs and groundwater. inform this assessment. 8.2.4 Desk Study The desk study collated existing data to form an understanding of the hydrology and hydrogeology of the Development. The desk study included: • Identification of catchments, watercourses, springs and water features; • Collation of data provided through consultations; • Collation of flood plain information and water quality data; and • Compilation of soils, geological and hydrogeological information. Reference was made to the following sources of information: • The British Geological Survey (BGS) Digital Mapping; • Hydrogeological Map of England and Wales 1:625,000, 1977; • The Ordnance Survey (OS) 1:50,000 Landranger Map (Sheet 103); and • OS 1:10,000 digital mapping. The Hydrology core study area (the area within the Development Site Boundary) and wider study area of 2 kilometres (km) from the proposed turbine locations is shown in Figure 8.1. 8.2.5 Site Walkover A site walkover was conducted on the 10th July 2012 to verify the findings of the desk study and to obtain an understanding of the local topography and hydrological regime. Weather conditions during the site walkover were characterised by persistent and heavy rainfall, whilst the preceding week had persistent rainfall. 8.2.6 Significance Criteria The significance of the potential effects of the Development have been classified by taking into account the sensitivity of receptors and the magnitude of the potential effect on them, combined with the likelihood of an event occurring as defined in Table 8.2. Kelda Water Services Arcus Renewable Energy Consulting Ltd October 2012 Page 8-3 Chapter 8 Gorpley Wind Farm Geology, Hydrology and Hydrogeology Environmental Statement