Glyn Rhonwy Pumped Storage Development Consent Order Appendix 7.5 Etive Ecology (2012) Glyn Rhonwy Pumped Storage Scheme: Llyn Padarn Freshwater Ecology Impact Assessment September 2012 Glyn Rhonwy Pumped Storage Final Environmental Statement Volume September Development Consent Order 3 2015 Glyn Rhonwy Pumped Storage Final Environmental Statement Volume September Development Consent Order 3 2015 This Appendix was previously submitted as part of the 2012 Environmental Statement. Where there are references to Quarry Battery Company (QBC), this now relates to Snowdonia Pumped Hydro (SPH) as this Appendix is submitted in support of the Development Consent Order (DCO) application. Glyn Rhonwy Pumped Storage Final Environmental Statement Volume September Development Consent Order 3 2015 ETIVEECOLOGY Glyn Rhonwy Pumped Storage Scheme: Llyn Padarn Freshwater Ecology Impact Assessment Produced by for September 2012 Glyn Rhonwy PS Freshwater Ecology Assessment Llanberis CONTENTS 1 INTRODUCTION 3 1.1 The Scheme 3 1.2 Purpose of this Report 3 2 METHODOLOGY 4 2.1 Desk Study 4 2.2 Consultation 4 2.3 Field Sampling 4 3 BASELINE INFORMATION 7 3.1 Site Designation 7 3.2 Designated Interest Features 8 Arctic Charr 8 Floating Water Plantain 13 3.3 Non-Designated Interest Features 15 Atlantic Salmon 15 Sea Trout (Brown Trout in Freshwater) 16 Small Quillwort 17 Otter 18 European Eel 20 Lamprey Species 21 4 CONSULTATIONS 23 4.1 Environment Agency Wales 23 4.2 CCW 24 4.3 Gwynedd Council 25 4.4 Summary 25 5 IMPACT ASSESSMENT 26 5.1 Potential Impacts 26 5.2 Assessment of Impacts: Construction 29 5.3 Assessment of Impacts: Abstraction 31 5.4 Assessment of Impacts: Operational Discharges 33 5.5 Assessment of Impacts: Decommissioning 36 6 MITIGATION 37 6.1 Construction 37 6.2 Abstraction 38 6.3 Operation 38 ETIVE ECOLOGY 1 www.etiveecology.co.uk Glyn Rhonwy PS Freshwater Ecology Assessment Llanberis 6.4 Decommissioning 39 7 Water Framework Directive Assessment 41 7.1 Introduction 41 7.2 Compliance with Mitigation Measures Required Under the WFD 41 7.3 Compliance with Biological Monitoring Elements of the WFD 43 7.4 Compliance with Llyn Padarn SSSI Objectives: Arctic Charr 44 7.5 Compliance with Llyn Padarn SSSI Objectives: Floating Water Plantain 45 8 CONCLUSION 1 8.1 Summary of Impacts 1 8.2 Monitoring Requirements 3 8.3 Water Framework Directive Assessment 3 9 REFERENCES 1 Quality Assessment Record Report Version Written by Date Reviewed by Date 1.0 Russell Grey 13 September 2012 Maddy Warriner 14 September 2012 2.0 Russell Grey 24 September 2012 Maddy Warriner 25 September 2012 and Maddy Warriner ETIVE ECOLOGY 2 www.etiveecology.co.uk Glyn Rhonwy PS Freshwater Ecology Assessment Llanberis 1 INTRODUCTION 1.1 The Scheme 1.1.1 The proposed Glyn Rhonwy Pumped Storage scheme is a small (49.9 MW) pumped hydroelectric electricity storage facility. The project plans to utilise the Glyn Rhonwy cascade of disused slate quarries to the north-west of Llanberis, Gwynedd. Electrical energy is stored in the scheme by pumping water from the lower reservoir, to the upper reservoir, converting electrical energy to gravitational energy. This energy can then be converted back to electricity when required such as during periods of sudden high demand. 1.1.2 The scheme will include the construction of two new dams, a turbine house, connecting pipework and a new spillway connecting Glyn Rhonwy to Llyn Padarn. The scheme will also abstract up to 2000m3 per day from Llyn Padarn for the initial filling of the upper reservoir (Chwarel Fawr) and subsequent topping-up only as required. The scheme will also discharge an average daily volume of up to 1200m3 into Llyn Padarn, principally during periods of wet weather. This discharge will be as a result of heavy rainfall into the system and represents the natural run-off that would normally enter the Llyn Padarn system. 1.1.3 The scheme is located immediately adjacent to the Snowdonia National Park (NP) and cascades down into the Llyn Padarn Site of Special Scientific Interest (SSSI), designated for its nationally important population of Arctic charr (Salvelinus alpinus L.) and habitats supporting floating water-plantain (Luronium natans) and small quillwort (Isoetes echinospora). The site also supports Atlantic salmon (Salmo salar), sea trout (Salmo trutta) and otter (Lutra lutra). 1.2 Purpose of this Report 1.2.1 The purpose of this report is to assess the potential impacts posed to the freshwater interest features relevant to the scheme and the surrounding freshwater environment. 1.2.2 This is done by establishing the baseline freshwater environment and data gathering, including consultations and data purchase, and identifying the sensitivities of the features present. The potential impacts of the scheme are then considered, identifying the nature and magnitude of these impacts on the interest features and the likelihood of occurrence. Appropriate mitigation measures and monitoring requirements are also considered and included in the assessment. 1.2.3 The report concludes whether there will be any likely significant impacts on any of the freshwater interest features as a result of the proposed scheme. ETIVE ECOLOGY 3 www.etiveecology.co.uk Glyn Rhonwy PS Freshwater Ecology Assessment Llanberis 2 METHODOLOGY 2.1 Desk Study 2.1.1 Llyn Padarn was identified early in the design of the scheme as a key ecological receptor, as a SSSI with a potential direct pathway linking it to the scheme, during both construction and operational phases. A desk study was therefore undertaken to identify the interest features of the site, the status of these features and to consider their sensitivities to changes in the freshwater environment. 2.1.2 The following sources of information were utilized: Countryside Council for Wales (CCW) website (http://www.ccw.gov.uk) Snowdonia National Park Biodiversity Action Plan (http://www.eryri-npa.gov.uk) Environment Agency Wales (EAW) website (http://www.environment-agency.gov.uk) Gwynedd County Council Biodiversity Action Plan (http://www.gwynedd.gov.uk/gwy_doc.asp?cat=3426&doc=9530&language=1&p=1&c=1) North Wales Environmental Information Service (Cofnod) (http://www.cofnod.org.uk) 2.1.3 An extensive internet search was also used to identify independent and unpublished information on the various species relevant to Llyn Padarn. In addition detailed survey and assessment reports were provided by CCW and EAW and are listed in the reference section (Chapter 9 of this report). Local surveyor knowledge was also applied where appropriate. 2.2 Consultation 2.2.1 The consultation process has been on-going throughout the design process for the scheme with various statutory consultees. This process has included specific discussions with regards to the freshwater interests associated with Llyn Padarn SSSI and the potential impacts resulting from the proposed scheme. 2.2.2 The following organisations have been consulted: CCW: G.J. Davies, Casework Officer (Scoping Opinion) EAW: Fisheries Technical Team, Environment Team, Planning Officer, Senior Development Management Officer, Permitting Support Team (Matthew Hazlewood, Victoria Briscoe, Gareth Thomas, Glyn Llewelyn Gruffudd) Gwynedd Council: Emily Meilleur, Senior Biodiversity Officer 2.2.3 A review of the issues raised during the consultation process is presented in Chapter 4 of this report. A full review of all environmental consultations undertaken in relation to the proposed scheme is found within the main Environmental Statement. 2.3 Field Sampling 2.3.1 During a meeting with the Environment Agency Wales (EAW) on 29 May 2012, the issue of background water quality was raised and the need to include appropriate information in the Environmental Statement was emphasised. As a result, water quality sampling has been undertaken at up to five locations within the Glyn Rhonwy study area to provide baseline data for consideration with the EIA process. Subsequent monitoring during and ETIVE ECOLOGY 4 www.etiveecology.co.uk Glyn Rhonwy PS Freshwater Ecology Assessment Llanberis post-construction can then be undertake using the same sampling points to identify any changes from the baseline. 2.3.2 The following surface water sampling points have been agreed: 1. The lake in Quarry 6, at a point close to the drainage adit. 2. The pipe discharge to the manhole below Quarry 7. 3. The inflow to the manhole below Quarry 7 from the south east. 4. The lake in Quarry 7 (if accessible). 5. The lake in the small quarry between Quarry 6 and Quarry 7 (if accessible). 2.3.3 Samples were taken from locations 1, 3, 4 and 5 on 30 July 2012. Location 2 was dry at the time of sampling. The samples have been submitted to an independent laboratory and analysed for the following suite of parameters: pH, alkalinity and electrical conductivity Metals: arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, zinc, aluminium, antimony, barium, boron, cobalt, lithium, iron, manganese, molybdenum, strontium Cyanide Calcium, magnesium, sodium, potassium, chloride and sulphate Nitrate, nitrite and ammonical nitrogen Orthophosphate Total petroleum hydrocarbons (speciated to TPHCWG, if total is greater than 0.2mg/l) PAH (16) BOD and COD 2.3.4 Results from the water sampling, indicate that the water quality at all sampling points is ‘satisfactory’ and with no obvious evidence of contamination. The analysis indicates that the water from sample point1, 3 and 5 have similar in chemistry, suggesting they are hydrologically linked. Water from sample poit4 is marginally different, suggesting a different water source. 2.3.5 An assessment of these results by a senior environmental scientist, Owen Tucker at AECOM, on behalf of QBC concluded that the quality of these waters does not pose a constraint to any of the proposed developments. Further information is provided in theChapter 8 (water resources) of the Environmental Statement. 2.4 Impact Assessment 2.4.1 The impact assessment conducted in this report follows the methodology outlined in the main ecology chapter of the Environmental Statement.