HAWARDEN POWER GENERATION PLANT INDUSTRIAL PARK, BROUGHTON

AIR QUALITY ASSESSMENT

March 2020 Report Ref: 01.0009.026 v1

Isopleth Ltd. Registered in and No. 9150373

Conrad (Hawarden) Limited Report Ref: 01.0009.026 v1 AQ Assessment: Hawarden Power Generation Plant March 2020

CONTENTS

1.0 INTRODUCTION ...... 4 1.1 Background ...... 4 1.2 Planning History ...... 4 1.3 Scope ...... 4 2.0 SITE DESCRIPTION ...... 5 2.1 Location ...... 5 2.2 Development Description ...... 5 3.0 REGULATORY STANDARDS AND GUIDELINES ...... 6 3.1 International Legislation and Policy ...... 6 3.2 Air Quality Strategy for England, Scotland, Wales & Northern Ireland...... 6 3.3 Local Air Quality Management (LAQM)...... 8 3.4 Medium Combustion Facility Directive (MCPD) ...... 9 4.0 ASSESSMENT METHODOLOGY ...... 11 4.1 Local Meteorological Data ...... 11 4.2 Topography...... 11 4.3 Building Downwash / Entrainment ...... 12

4.4 Nitric Oxide to NO2 Conversion ...... 12 4.5 Sensitive Human Health Receptors ...... 12 4.6 Sensitive Habitats and Ecosystems ...... 13 4.6.1 River Dee and ...... 14 4.6.2 and Buckley Newt sites ...... 14 4.6.3 The (Wales) SAC, RAMSAR and SPA ...... 15 4.6.4 Summary...... 15 4.7 Significance of Impact ...... 16 4.7.1 Stage 1 ...... 16 4.7.2 Stage 2 ...... 16 5.0 BASELINE CONDITIONS ...... 18 5.1 Council Review and Assessment of Air Quality ...... 18 5.2 Local Monitoring Data ...... 18 5.3 DEFRA Background Maps ...... 19 6.0 PREDICTED IMPACTS ...... 20 6.1 Human Receptors ...... 20 6.2 Ecological Receptors ...... 20

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6.2.1 Critical Levels ...... 20 6.2.2 Nutrient N Critical Loads ...... 21 6.3 Summary...... 21 6.3.1 For human health receptors ...... 21 6.3.2 For ecological receptors ...... 22 6.4 Suitability for Permitting ...... 22 7.0 CONCLUSIONS ...... 24 DRAWING AQ1 ...... 25 APPENDIX A: INPUT DATA ...... 27 APPENDIX B: WIND DATA ...... 28 APPENDIX C: AIR QUALITY LIMITS ...... 29 APPENDIX D: IMPACT PLOTS ...... 30 APPENDIX E: ECOLOGICAL SITES ...... 33

[Copyright notice: Unless otherwise noted, all OS drawings used in this report are subject to Crown copyright and database rights 2019 Ordnance Survey 0100031673]

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1.0 INTRODUCTION

1.1 Background

This air quality assessment has been undertaken by Isopleth Ltd further to instruction by Enzygo Ltd on behalf of Conrad (Hawarden) Limited. The assessment considers air quality impacts associated with a proposed fuelled electricity generation plant at the proposed Hawarden Power Generation Plant, Hawarden Industrial Park, Close, Broughton, CH5 3PZ (Figure 1). The site lies within the administrative area of Flintshire Council. The impacts of the proposed power plant on local air quality has been assessed. The type, source and significance of potential impacts are identified and the measures employed to minimise these impacts are described. The key pollutants associated with operation of the spark ignition engines considered in this assessment are oxides of nitrogen (NOx as NO2), identified in the Medium Combustion Plant Directive (MCPD) as the primary pollutants arising from the combustion of natural gas, for which there is a quantitative limit. Other pollutants, such as sulphur dioxide (SO2), sometimes associated with the operation of spark ignition engines (when run on biogas) are generated in negligible levels when using this fuel type and there is no MCPD limit for carbon monoxide (CO). Predicted ground level concentrations of NO2 are compared with relevant air quality standards and guidelines for the protection of human health and sensitive habitats.

1.2 Planning History

The site benefits from an existing permission for a construction (and operation) of a 2.5MW Flexible Gas Fired Power Plant, which was approved on 1st March 2019 (Application Ref: 059150): • Proposal: Construction of a 2.5MW Flexible Gas Fired Power Plant • Location: Land to the rear of Wirral Fospray Ltd, Clwyd Close, Manor Lane, Hawarden Industrial Park, Deeside, CH5 3PZ This application was supported by a Dispersion Modelling Assessment prepared by REC (REC reference: AQ106386R4) in October 2018. The modelling assumed that the plant would be in use for a maximum of 1500 hours per year. The committee report confirmed that Public Protection had no adverse comments to make regarding this proposal and that Policy GEN1 supports development where it does not have a significant adverse impact on users of adjacent land or the in general through the adverse effects of pollution.

1.3 Scope

This detailed assessment report relates to the impact of air pollutants from the operation of the power plant. Results of the dispersion modelling for engine exhaust emissions are presented in terms of concentrations, with a description of magnitude and also determination of significance where relevant.

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2.0 SITE DESCRIPTION

2.1 Location

The site is located at a site within the Hawarden Industrial Park. The approximate National Grid Reference for the site is 333915, 364885. A location plan for the site is presented as Drawing AQ1, the closest residences are located at: • Cwrt Cwellyn; • Little Roodee; • Manor Court; • Manor Close; • St Mary's Way; and • Broughton Lodge.

2.2 Development Description

The site will operate on a largely unmanned basis and will be remotely operated by Conrad (Hawarden) Limited. The standby, natural gas fuelled spark ignition engine provides balance to the National Grid during unexpected periods of high demand for electricity or where there are constraints on electricity available in England and Wales. Generally, a power plant operates fewer than 600 hrs per year, about 7% of the time, almost entirely during the winter months. This air quality assessment assumes that the engine will operate for a maximum of 3000 hours per year. The proposed Conrad (Hawarden) Limited facility will comprise a single natural gas fuelled 2.535MW MTU 20V4000L64FN spark ignition engine for electricity generation. Emissions to air are via a single engine exhausts of 7m in height.

3 The NOx emission concentration of the engine is 250 mg/Nm at 5% O2, 0 degC, 1atm, dry. This may be converted to differing oxygen concentrations using the equation in MCERTS monitoring Guidance M2 Box 3.5. In this case, the concentration may also be expressed as 3 93.75 mg/Nm at 15% O2, 0 degC, 1atm, dry.

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3.0 REGULATORY STANDARDS AND GUIDELINES

The Environmental Permitting process in Wales is regulated by Natural Resources Wales. However, much of the guidance used in relation to Environmental Permitting is shared with the Environment Agency1. For this reason, references made below to Environment Agency Guidance can be taken for these documents to also mean Guidance used (or referenced by) Natural Resources Wales.

3.1 International Legislation and Policy

European Directive 2008/50/EC of the European Parliament and of the Council of 21st May 2008, sets legally-binding Europe-wide limit values for the protection of public health and sensitive habitats. The Directive streamlines the European Union’s air quality legislation by replacing four of the five existing Air Quality Directives within a single, integrated instrument.

The pollutants included are sulphur dioxide (SO2), nitrogen dioxide (NO2), particulate matter of less than 10 micrometres (µm) in aerodynamic diameter (PM10), particulate matter of less than 2.5 µm in aerodynamic diameter lead (PM2.5), lead (Pb), carbon monoxide (CO), benzene (C6H6), ozone (O3), polycyclic aromatic hydrocarbons (PAHs), cadmium (Cd), arsenic (As), nickel (Ni) and mercury (Hg). Directive 2008/50/EC makes it clear that the ambient air quality standards shall not be enforced where there is no regular public access and fixed habitation: ‘2. Compliance with the limit values directed at the protection of human health shall not be assessed at the following locations: (a) any locations situated within areas where members of the public do not have access and there is no fixed habitation; (b) in accordance with Article 2(1), on factory premises or at industrial installations to which all relevant provisions concerning health and safety at work apply; (c) on the carriageway of roads; and on the central reservations of roads except where there is normally pedestrian access to the central reservation.’ The Environmental Permitting (England and Wales) (Amendment) (EU Exit) Regulations 2019 (SI 2019/39) were made on 8 January 2019 and came into force on exit day. The Regulations ensure that the Environmental Permitting (EP) regime in England and Wales can continue to function after Brexit.

3.2 Air Quality Strategy for England, Scotland, Wales & Northern Ireland

The Government's policy on air quality within the UK is set out in the Air Quality Strategy (AQS) for England, Scotland, Wales and Northern Ireland (AQS) published in July 2007, pursuant to the requirements of Part IV of the Environment Act 1995. The AQS sets out a

1https://naturalresources.wales/permits-and-permissions/environmental-permits/horizontal- guidance/?lang=en

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framework for reducing hazards to health from air pollution and ensuring that international commitments are met in the UK. The AQS is designed to be an evolving process that is monitored and regularly reviewed. The AQS sets standards and objectives for ten main air pollutants to protect health, vegetation and ecosystems. The air quality standards are long-term benchmarks for ambient pollutant concentrations which represent negligible or zero risk to health, based on medical and scientific evidence reviewed by the Expert Panel on Air Quality Standards (EPAQS) and the World Health Organisation (WHO). These are general concentration limits, above which sensitive members of the public (e.g. children, the elderly and the unwell) might experience adverse health effects. The air quality objectives are medium-term policy based targets set by the Government which take into account economic efficiency, practicability, technical feasibility and timescale. Some objectives are equal to the EPAQS recommended standards or WHO guideline limits, whereas others involve a margin of tolerance, i.e. a limited number of permitted exceedences of the standard over a given period. For some pollutants there is both a long-term (annual mean) standard and a short-term standard. In the case of NO2, the short-term standard is for a 1-hour averaging period, whereas for CO it is the 8-hour averaging period. These periods reflect the varying impacts on health of differing exposures to pollutants. Table 3-1 Air Quality Strategy Objectives

Pollutant Concentrations Measured As 200 µg/m3 not to be exceeded more 1 hour mean Nitrogen Dioxide (NO2) than 18 times per year 40 µg/m3 Annual mean

The health studies which provide the basis for the air quality standards are based on data for individuals within a population, and therefore the exposure should relate to that of an individual. For the purposes of LAQM, regulations state that exceedances of the objectives should be assessed in relation to ‘the quality of the air at locations which are situated outside of buildings or other natural or man-made structures, above or below ground, and where members of the public are regularly present’. Examples of where the objectives should, and should not apply, are summarised in Table 3-2 below, as taken from DEFRA Guidance LAQM TG(16). This table should be considered in the context of the conclusions of various review documents such as The AQC report2 Relationship between the UK Air Quality Objectives and Occupational Air Quality Standards (November

2http://www.aqconsultants.co.uk/AQC/media/Reports/Relationship-between-the-UK-Air-Quality- Objectives-and-Occupational-Air-Quality-Standards.pdf

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2016). In particular it is important that, when setting the objective, DEFRA took account of EPAQs’s recommendations. It was also influenced by the limit value set in European Commission’s First Air Quality Daughter Directive which made it clear that it only applied to ‘outdoor air in the troposphere, excluding work places’. The Ambient air quality Directive is consistent with this, stating that ‘Compliance with the limit values directed at the protection of human health shall not be assessed… on factory premises or at industrial installations to which all relevant provisions concerning health and safety at work apply’. As such, commercial / industrial occupiers of industrial units would therefore be outside the requirements of the air quality objectives. Occupiers of industrial units where members of the public would ‘regularly be present’ are however within the requirements. Table 3-2 Air Quality Strategy Objectives

Averaging Objectives should apply at: Objectives should generally not apply Period at: Annual mean All locations where members of the Building façades of offices or other public might be regularly exposed. places of work where members of the Building façades of residential public do not have regular access. properties, schools, hospitals, care Hotels, unless people live there as homes etc. their permanent residence. Gardens of residential properties. Kerbside sites (as opposed to locations at the building façade), or any other location where public exposure is expected to be short term. 24-hour mean All locations where the annual mean Kerbside sites (as opposed to locations and 8-hour objective would apply, together with at the building façade), or any other mean hotels. Gardens of residential location where public exposure is properties expected to be short term. 1-hour mean All locations where the annual mean Kerbside sites where the public would and: 24 and 8-hour mean objectives not be expected to have regular apply. Kerbside sites (for example, access. pavements of busy shopping streets). Those parts of car parks, bus stations and railway stations etc. which are not fully enclosed, where members of the public might reasonably be expected to spend one hour or more. Any outdoor locations where members of the public might reasonably expected to spend one hour or longer.

3.3 Local Air Quality Management (LAQM)

Part IV of the Environment Act 1995 also requires local authorities to periodically Review and Assess the quality of air within their administrative area. The Reviews have to consider the

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present and future air quality and whether any air quality objectives prescribed in Regulations are being achieved or are likely to be achieved in the future. Where any of the prescribed air quality objectives are not likely to be achieved the authority concerned must designate that part an Air Quality Management Area (AQMA). For each AQMA, the local authority has a duty to draw up an Air Quality Action Plan (AQAP) setting out the measures the authority intends to introduce to deliver improvements in local air quality in pursuit of the air quality objectives. Local authorities are not statutorily obliged to meet the objectives, but they must show that they are working towards them. The Department of Environment, Food and Rural Affairs (DEFRA) has published technical guidance for use by local authorities in their Review and Assessment work. This guidance is commonly referred to as LAQM.TG(16). Full details are available on the DEFRA website.

3.4 Medium Combustion Facility Directive (MCPD)

Directive (EU) 2015/2193 of the European Parliament and the Council of 25th November 2015 on the limitation of emissions of certain pollutants into the air from medium combustion facilities (Medium Combustion Plant (MCP) Directive) regulates pollutant emissions from the combustion of fuels in facilities with a rated thermal input equal to or greater than 1 megawatt (MWth) and less than 50 MWth. The MCPD entered into force on 18th December 2015 and has been transposed into the Environmental Permitting Regulations, most recently through The Environmental Permitting (England and Wales) (Amendment) Regulations 2018 No. 110. The MCPD regulates emissions of NOx, SO2, and particulate matter (PM10) into the air with the aim of reducing those emissions and the risks to human health and the environment they may cause. It also lays down rules to monitor emissions of carbon monoxide (CO). Environment Agency has issued guidance relating to MCPD regulation and assessment, including: ‘Emissions from specified generators (Version 1). Guidance on dispersion modelling for oxides of nitrogen assessment from specified generators.’ This EA guidance states that it is intended for use with:

3 • Tranche A generators that have NOX emissions greater than 500 mg/Nm (at 273.15 K, 101.3 kPa, 0% moisture and 15% oxygen), with aggregated rated thermal inputs of greater than 5 MWth and operating more than 50 hours per year; 3 • Tranche B generators with NOX emissions less than 190 mg/Nm , with aggregated thermal inputs greater than 1 MWth and operating more than 50 hours per year where there is a higher risk of NOX impacts. For example, where the facility is located in or near an Air Quality Management Area (AQMA) declared for NO2, or operates for more than 500 hours per year.

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These include former Tranche A generators with transitional arrangements of:

3 • NOX emissions less than 500 mg/Nm with aggregated rated thermal inputs greater than 5 MWth; and aggregated rated thermal inputs less than 5 MWth. This detailed air quality assessment is compliant with the requirements of the EA (and NRW) guidance. NRW has also issued a separate regulatory guidance note (RGN) How to comply with your environmental permit. Additional guidance for: Combustion Activities (EPR 1.01).

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4.0 ASSESSMENT METHODOLOGY

The scope of the impact assessment for stack emissions from the proposed plant has been determined in the following way: • review of air quality data for the area surrounding the Site, including data from the Defra Air Quality Information Resource (UK-AIR) and the Air Pollution Information System (APIS); • desk study to confirm the location of nearby areas that may be sensitive to changes in local air quality; and • review of emission parameters for the power plant and dispersion modelling using the Breeze AERMOD 8 dispersion model (version 18081) to predict ground-level concentrations of pollutants at sensitive human and habitat receptor locations. Manufacturer emission limits have been assumed for the purposes of the modelling assessment and each engine is assumed to be operating at full load for a maximum of 3000 hours in the year. The input parameters used in the assessment are identified in Appendix A.

4.1 Local Meteorological Data

The dispersion modelling has been carried out using five years (2014-2018) of hourly sequential meteorological data in order to take account of inter-annual variability and reduce the effect of any atypical conditions. Data from the Hawarden meteorological station has been used for the assessment. This site is the most representative data currently available for the area which provides the level of completeness required for dispersion modelling (i.e. minimal missing data). The meteorological data has been prepared based on a surface roughness of 0.3m with the Albedo / Bowen is characterised as grassland (50%), deciduous forest (10%) and urban (40%). A windrose for all years of meteorological data are presented in Appendix B.

4.2 Topography

The presence of elevated terrain can significantly affect the dispersion of pollutants and the resulting ground level concentration in a number of ways. Elevated terrain reduces the distance between the plume centre line and the ground level, thereby increasing ground level concentrations. Elevated terrain can also increase turbulence and, hence, plume mixing with the effect of increasing concentrations near to a source and reducing concentrations further away. The power plant lies at a basal elevation of around 9m AoD. Topography has been incorporated within the dispersion model. AERMOD utilises digital elevation data to determine the impact of topography on dispersion from a source. Topographical data for the site has been obtained in OS digital (.ntf) format.

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Data was processed by the AERMAP function within AERMOD to calculate terrain heights, and interpolate data to calculate terrain heights for sources, buildings etc.

4.3 Building Downwash / Entrainment

The presence of buildings close to emission sources can significantly affect the dispersion of pollutants by leading to downwash. This occurs when a building distorts the wind flow, creating zones of increased turbulence. Increased turbulence causes the plume to come to ground earlier than otherwise would be the case and result in higher ground level concentrations closer to the stack. Downwash effects are only significant where building heights are greater than 40% of the emission release height. The downwash structures also need to be sufficiently close for their influence to be significant. The engine container is approximately 4.5m in height and has been included in the dispersion model to account for potential downwash effects and allow for stack height determination. A single site building to the immediate west of the container has also been included at 4m. All other buildings / structures within 5 stack heights are lower than 40% of the stack and are therefore not relevant to the model.

4.4 Nitric Oxide to NO2 Conversion

Oxides of nitrogen (NOx) emitted to atmosphere as a result of combustion will consist largely of nitric oxide (NO), a relatively innocuous substance. Once released into the atmosphere, NO is oxidised to NO2. The proportion of NO converted to NO2 depends on a number of factors including wind speed, distance from the source, solar irradiation and the availability of oxidants, such as ozone (O3).

A conversion ratio of 70% NOx:NO2 has been assumed for comparison of predicted concentrations with the long-term objectives for NO2. A conversion ratio of 35% has been utilised for the assessment of short-term impacts, as recommended by Environment Agency and NRW guidance3.

4.5 Sensitive Human Health Receptors

The term 'sensitive receptors' includes any persons, locations or systems that may be susceptible to changes as a consequence of the proposed power plant. As described in section 3.2 of this report, annual objectives only apply at residences. A selection of the closest receptors to the development which have been used for modelling purposes are shown in Table 4.1 and are also shown on Drawing AQ1.

3 AQMAU, Conversion Rates for NOx and NO2.

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Table 4-1 Modelled Receptors

Reference Description OS GR Xm OS GR Ym Distance from stack (m) D1 Office South West of Site 333818 364888 96 D2 Dee Tech Office 333867 364966 92 D3 1 Cwrt Cwellyn 333650 365059 315 D4 4 Little Roodee 333739 365227 383 D5 14 Little Roodee 333768 365258 399 D6 10 Manor Court 333947 365352 467 D7 30 Manor Close 334112 365366 519 D8 16 St Mary's Way 334355 364107 896 D9 Park House, St Mary's Way 334102 364087 821 D10 Broughton Lodge 333242 364461 796 It is recognised that this list is not exhaustive, however these receptors have been selected in order to provide an indication of impacts in all directions from the proposed plant. They are also consistent with those receptors used in the REC air quality assessment of October 2019 and were therefore considered by Flintshire Public Protection as acceptable locations. Impacts have also been assessed by use of a receptor grid at 20m (i.e. 3 stack heights) resolution across the model domain. These results have been presented as impact isopleths and this allows the concentration at all locations to be determined. These predicted ground level concentrations may then be compared with relevant long term air quality standards and guidelines for the protection of health.

4.6 Sensitive Habitats and Ecosystems

The presence of the following habitat sites have been assessed: • Special Areas of Conservation (SACs) and candidate SACs (cSACs) designated under the EC Habitats Directive4; • Special Protection Areas (SPAs) and potential SPAs designated under the EC Birds Directive5; • Ramsar Sites designated under the Convention on Wetlands of International Importance6. • Sites of Special Scientific Interest (SSSI); • National Nature Reserves (NNR); and • ancient woodland.

4 Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora. 5 Council Directive 79/409/EEC on the conservation of wild birds. 6 Ramsar (1971), The Convention of Wetlands of International Importance especially as Waterfowl Habitat.

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Where sensitive ecological receptors are present, maximum predicted ground level concentrations of NOx are compared with relevant critical levels, thresholds of airborne pollutant concentrations above which damage may be sustained to sensitive plants and animals. The development is not a significant source of SO2 or HCL / HF. Critical loads refer to the threshold beyond which deposition of pollutants to water or land results in measurable damage to vegetation and habitats. The maximum predicted deposition rates are compared with site specific critical loads obtained from APIS. MAGIC searches for areas 10km (European sites) and 2km from the site (SSSI, AW and local sites) are included in Appendix E. 4.6.1 River Dee and Bala Lake The River Dee and Bala Lake Designated Special Area of Conservation (SAC) covers an area of 1271.32ha and consists of: • Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (4%); • Salt marshes, Salt pastures, Salt steppes (2%); • Inland water bodies (Standing water, Running water) (90%); • Improved grassland (2%); and • Broad-leaved deciduous woodland (2%). Of relevance to the Hawarden Power Generation plant is the Afon Dyfrdwy (River Dee) SSSI which forms part of the SAC and is closest the development site. The location of and citation for this SSSI is included within Appendix E. 4.6.2 Deeside and Buckley Newt sites The Deeside and Buckley Newt sites Designated Special Area of Conservation (SAC) covers an area of 206.19 ha and consists of: • Inland water bodies (Standing water, Running water) (1.9%); • Bogs, Marshes, Water fringed vegetation, Fens (0.2%); • Heath, Scrub, Maquis and Garrigue, Phygrana (5.3%); • Dry grassland, Steppes (3.5%); • Humid grassland, Mesophile grassland (1.2%); • Improved grassland (40.5%); • Broad-leaved deciduous woodland (30.4%); • Coniferous woodland (2.9%); • Mixed woodland (4%); and • Other land (including Towns, Villages, Roads, Waste places, Mines, Industrial sites) (10.1%)

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Of relevance to the Hawarden Power Generation plant are the following SSSI which form part of the SAC and is closest the development site. • Connah's Quay Ponds And Woodland SSSI; • Buckley Claypits And Commons SSSI; and • Maes Y Grug SSSI. The locations of and citation for these SSSI are included within Appendix E. 4.6.3 The Dee Estuary (Wales) SAC, RAMSAR and SPA The Dee Estuary (Wales) covers an area of 15805.27ha. The SAC consists of: • Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (81.8%); • Salt marshes, Salt pastures, Salt steppes (16.1%); • Coastal sand dunes, Sand beaches, Machair (0.7%); • Shingle, Sea cliffs, Islets (0.5%); • Bogs, Marshes, Water fringed vegetation, Fens (0.4%); • Humid grassland, Mesophile grassland (0.2%); • Improved grassland (0.1%); • Broad-leaved deciduous woodland (0.1%); and • Other land (including Towns, Villages, Roads, Waste places, Mines, Industrial sites) (0.1%) Of relevance to the Hawarden Power Generation plant is the Dee Estuary / Aber Afon Dyfrdwy SSSI which forms part of the SAC and is closest the development site. The location of and citation for this SSSI is included within Appendix E. 4.6.4 Summary The closest points within the above sites have been modelled. These are shown in Table 4-2, below. Table 4-2 Modelled Receptors: Ecological

Reference Description OS GR Xm OS GR Ym ECO1 River Dee and Bala Lake 1 337567 365325 ECO2 River Dee and Bala Lake 2 336986 365679 ECO3 River Dee and Bala Lake 3 336405 366033 ECO4 River Dee and Bala Lake 4 335824 366387 ECO5 River Dee and Bala Lake 5 335243 366741 ECO6 River Dee and Bala Lake 6 334662 367095

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Reference Description OS GR Xm OS GR Ym ECO7 River Dee and Bala Lake 7 334082 367448 ECO8 River Dee and Bala Lake 8 333501 367802 ECO9 River Dee and Bala Lake 9 332920 368156 ECO10 River Dee and Bala Lake 10 332339 368510 ECO11 River Dee and Bala Lake 11 331758 368864 ECO12 River Dee and Bala Lake 12 331177 369218 ECO13 Deeside and Buckley Newt sites 1 329884 368075 ECO14 Deeside and Buckley Newt sites 2 329185 367250 ECO15 Deeside and Buckley Newt sites 3 329312 365162 ECO16 Deeside and Buckley Newt sites 4 329479 363876 ECO17 Deeside and Buckley Newt sites 5 326431 366464 ECO18 The Dee Estuary (Wales) RAMSAR and SPA 331169 369226 A summary of critical levels for the protection of sensitive ecosystems and vegetation is presented in Appendix C.

4.7 Significance of Impact

The Natural Resources Wales significance criteria for Environmental Permitting follows that of the Environment Agency. 4.7.1 Stage 1 The EA Guidance describes that, to screen out a PC for any substance so that no further assessment is needed for that pollutant, the PC must meet both of the following criteria: • the short-term PC is less than 10% of the short-term environmental standard; • the long-term PC is less than 1% of the long-term environmental standard If both of these criteria are met no further assessment of the substance is required. There will be a need to carry out a second stage of screening to determine the impact of the PEC if the criteria are not met. 4.7.2 Stage 2 The EA Guidance describes that, in the second stage of screening if both of the following requirements are met there is no requirement for any further assessment of that substance. Detailed modelling will be required for emissions that don’t meet both of the following requirements: • the short-term PC is less than 20% of the short-term environmental standards minus twice the long-term background concentration; and • the long-term PEC is less than 70% of the long-term environmental standards The guidance then states that no further action is needed if the assessment has shown that both of the following apply:

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• emissions comply with BAT associated emission levels (AELs) or the equivalent requirements where there is no BAT AEL; and • the resulting PECs are not predicted to exceed environmental standards A cost benefit analysis is required if any of the following apply: • PCs could cause a PEC to exceed an environmental standard (unless the PC is very small compared to other contributors); • the PEC is already exceeding an environmental standard; • the activity or part of it isn’t covered by a ‘BAT reference document’ (BREF); • the emissions from the facility don’t comply with BAT AELs; or • a BAT assessment has been requested. If the emissions from the facility that affect ecological sites meet both of the following criteria, they are insignificant: • the short-term PC is less than 10% of the short-term environmental standard for protected conservation areas; and • the long-term PC is less than 1% of the long-term environmental standard for protected conservation areas If these requirements are not met there is a need to calculate the PEC and check the PEC against the standard for protected conservation areas. • If your long-term PC is greater than 1% and the PEC is less than 70% of the long-term environmental standard, the emissions are insignificant and there is no requirement to assess them any further; however • If the PEC is greater than 70% of the long-term environmental standard, detailed modelling is required.

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5.0 BASELINE CONDITIONS

5.1 Council Review and Assessment of Air Quality

The Authorities Collaborative Project (NWACP) has issued a 2019 Air Quality Progress Report In fulfilment of Part IV of the Environment Act 1995 Local Air Quality Management. The NWACP includes: • Isle of Anglesey County Council (IACC); • Conwy County Borough Council (CCBC); • Denbighshire County Council (DCC); • Flintshire County Council (FCC); • Gwynedd Council (GC); and • County Borough Council (WCBC). The 2019 Progress Report confirms that: ‘The North Wales Authorities have not declared any Air Quality Management Areas (AQMAs) and as a result, have not published an Action Plan. Air quality monitoring is undertaken by all six local authorities with a total of five automatic monitoring stations measuring nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) concentrations and 172 NO2 diffusion tube monitoring sites, located at key locations within town centres and along main transport links.’ The site is therefore not within an AQMA and does not have the potential to affect an AQMA.

5.2 Local Monitoring Data

FCC undertook monitoring at 53 locations, including duplicate diffusion tube monitoring at 3 sites (3 Davies Cottage, 20/22 Glynne Way and Llys Alun) and triplicate diffusion tubes monitoring at one site (South Bank, Aston Park, Queensferry CH5 1XZ). None of the monitoring results are directly relevant to the proposed development, with the cloest being: • Site 33: 133, Main Road, Broughton CH4 0NR (Kerbside). OSGR 333568, 363511 • Site 49: 31, The Rowans, Broughton CH4 0TD (Kerbside). OSGR 333531, 363028 • Site 4: CH5 3DL (Kerbside). 330614, 366195 • Site 12/13: 20/22 Glynne Way, Hawarden (Kerbside). 331648, 365730 • Site 50: Ysgol Estyn Hawarden Road Hope LL12 9NL (Kerbside). 330898, 357996

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The monitoring results for these sites are as follows: Table 5-1 FCC Monitoring

Reference 2016 2017 2018 Site 33 26.9 23.8 24.8 Site 49 18.8 16.2 16.6 Site 4 18.0 16.0 16.0 Site 12/13 34.0 34.5 33.9 Site 50 16.9 15.3 16.6 The highest results is therefore on the main road through Hawarden (the B5125) and all results are well below the annual average limit for NO2.

5.3 DEFRA Background Maps

Additional information on background concentrations in the vicinity of the development site has been obtained from the DEFRA background pollutant maps. Background concentrations from grid square 334500, 364500 which represents the site for the current year of 2020 are given as 19.53 (µg/m3). Estimated DEFRA background concentrations are therefore ‘well below’ the relevant objectives.

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6.0 PREDICTED IMPACTS

The assessment results are presented in the tables below.

6.1 Human Receptors

The predicted process contribution (PC) and predicted environmental concentration (PEC) at the assessed receptor locations, where members of the public would reasonably be expected to spend time, is presented in Table 6.1. Table 6-1 Receptor Impact Concentrations (µg/m3)

PC PEC PC PEC Receptor Ref Annual NO2 Annual NO2 1-hr NO2 1-hr NO2 D1 ------7.1 46.2 D2 ------18.3 57.4 D3 0.11 19.6 5.0 44.1 D4 0.23 19.8 4.5 43.5 D5 0.21 19.7 4.3 43.3 D6 0.10 19.6 3.2 42.3 D7 0.07 19.6 2.9 41.9 D8 0.04 19.6 1.5 40.6 D9 0.02 19.6 1.2 40.2 D10 0.01 19.5 1.3 40.3

Maximum predicted impacts can be seen in Appendix D. The highest long term NO2 impact at a receptor where this limit applies is predicted to fall at receptor D4 (4 Little Roodee) which is 0.6% of the annual objective. The highest hourly NO2 impact at a receptor where this limit applies is predicted to fall at receptor D2 (Dee Tech Office) which is 9.2% of the annual objective. All long and short term impacts are therefore insignificant.

6.2 Ecological Receptors

6.2.1 Critical Levels The impacts at all locations (annual and 24-hour) can be seen in Appendix E. Table 6-2 Receptor Impact Process Contribution (µg/m3)

PC % of Limit PC % of Limit Site Annual NO2 Annual NO2 24-hr NO2 24-hr NO2 River Dee and Bala Lake 0.02 0.07% 0.2 0.27% Deeside and Buckley Newt sites 0.01 0.02% 0.1 0.13% The Dee Estuary (Wales) 0.01 0.04% 0.1 0.15% RAMSAR and SPA

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It can be seen that:

• The annual average NO2 impact is predicted to be, at worst 0.07% of the critical level at an ecological receptor and is therefore insignificant; and

• The 24 hour average NO2 impact is predicted to be, at worst 0.27% of the critical level and is therefore insignificant. 6.2.2 Nutrient N Critical Loads In terms of nutrient nitrogen critical loads at the three locations, the results are as follows: Table 6-3 Nutrient Nitrogen PC

PC lower critical load PC (% of lower Site Kg N/ha/yr Kg N/ha/yr critical load) River Dee and Bala Lake 0.003 3.00 0.10% Deeside and Buckley Newt sites 0.002 10.00 0.02% The Dee Estuary (Wales) RAMSAR and SPA 0.002 8.00 0.02% The nutrient nitrogen critical load impact is predicted to be, at worst <0.01% of the lower critical load at an ecological receptor and is therefore insignificant. The acid critical load impact will also therefore be insignificant.

6.3 Summary

6.3.1 For human health receptors As noted in Section 6.1 and shown in appendix D, for the worst case receptor the predicted short term and long term NO2 PCs are ‘insignificant’ for human health. In relation to all impacts: • The highest short term PC at any location outside the site boundary is 21.6 μg/m3 which is 10.8% of the EAL (200 μg/m3). As this is above the 10% threshold, this short term prediction at the point of maximum GLC cannot be considered ‘insignificant’; • The highest long term PC is 0.5 μg/m3 which is 1.3% of the EAL (40 μg/m3). As this is above the 1% threshold, this long term prediction cannot be considered ‘insignificant’. The short term and long term PCs at the point of maximum GLC have not screened out, but the PEC in both cases is less than 100% (30.3% and 50.2%, respectively) of the associated EALs. At locations where the hourly and / or annual objectives must be applied, levels are well below the relevant NO2 objectives. Therefore it can be concluded that the predicted short term and long term PECs at the sensitive human receptors are ‘not significant’, and are therefore unlikely to be a significant contributor to or cause an exceedance of an EAL. No further mitigation is required, beyond that already in place (i.e. stack height and use of lean burn engines).

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6.3.2 For ecological receptors As shown in Table 6-2, the predicted short term (24-hour) and long term mean for NOx emissions at the European sites are considered ‘not significant’ at less than 0.1%. For this reason, there is no requirement to consider PEC at this site. This is the same as for nutrient nitrogen, at less than 0.01% of the lowest critical load. The acid critical load impact will also therefore be insignificant. No further mitigation is required, beyond that already in place (i.e. stack height and use of lean burn engines).

6.4 Suitability for Permitting

EA Guidance ‘Environmental permitting: air dispersion modelling reports’ (24th May 2019) states that: ‘You must include a discussion of results (what they mean and their significance) before you make your final conclusions.’ However: ‘At the detailed modelling stage there are no criteria to determine whether: • PCs are significant • PECs are insignificant or significant’ In addition, Environment Agency Guidance ‘Air emissions risk assessment for your environmental permit’ states the following in relation to the requirements for further action, based on the results of the detailed modelling. When you don’t need to take further action ‘You don’t need to take further action if your assessment has shown that both of the following apply: • your proposed emissions comply with BAT associated emission levels (AELs) or the equivalent requirements where there is no BAT AEL • the resulting PECs won’t exceed environmental standards’ However: When you need to take further action. You’ll need to do a cost benefit analysis if any of the following apply: • your PCs could cause a PEC to exceed an environmental standard (unless the PC is very small compared to other contributors – if you think this is the case contact the Environment Agency) • the PEC is already exceeding an environmental standard

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• your activity or part of it isn’t covered by a ‘BAT reference document’ (BREF) • your proposals don’t comply with BAT AELs - in this case you’ll need to make a request for an exception (‘derogation’) that includes a cost benefit analysis of your proposals • you’ve been asked to do a BAT assessment At locations where the hourly and / or annual objectives must be applied, levels are below the relevant NO2 objectives. Therefore: 1. Emissions from the generators comply with BAT associated emission levels (AELs); and 2. the PCs will not cause a PEC to exceed an environmental standard at locations where the hourly and / or annual objectives must be applied; and 3. the PEC is not already exceeding an environmental standard at locations where the hourly and / or annual objectives must be applied. The proposed power generation plant is also compliant with How to comply with your environmental permit. Additional guidance for: Combustion Activities (EPR 1.01). For these reasons, it is acceptable for NRW to issue a Permit for this site when comparing the impacts against their assessment criteria.

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7.0 CONCLUSIONS

An assessment has been carried out to determine the local air quality impacts associated with the operation of a proposed power plant on a site in Flintshire. Detailed air quality modelling using the AERMOD 8 dispersion model has been undertaken to predict the impacts associated with stack emissions from the gas engines at the Site. As a worst-case, emissions from each of the stacks have been assumed to occur for 3000 hours per year when comparing against long term air quality limits and the entire year when comparing against short term limits. Actual operational hours are likely to be significantly lower. All impacts, human and ecological, are predicted to be below limit values at locations where the Air Quality Directive states that they must be applied. When applying the theoretical worst case assumptions above (i.e. that each of the engines is operating for 3000 hours) it can be seen that there is no realistic potential for a breach of the air quality objectives at any site. In summary, it can be concluded that the predicted short term and long term PECs at the sensitive human and ecological receptors are ‘not significant’, and are therefore unlikely to be a significant contributor to or cause an exceedance of an EAL (or upper critical load / level). For these reasons, it is acceptable for NRW to issue a Permit for this site when comparing the impacts against their assessment criteria.

Notice: This report was produced by Isopleth Ltd to present the results of an air quality constraints assessment for a proposed power plant at a site in Hawarden. This report may not be used by any person (or organisation) other than Conrad (Hawarden) Limited without express permission. In any event, Isopleth Ltd accepts no liability for any costs, liabilities or losses arising as a result of the use of or reliance upon the contents of this report by any person (or organisation) other than Conrad (Hawarden) Limited.

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DRAWING AQ1

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Catherine 1 Court (Llys Catrin) Park Industrial Hawarden Tank Conveyors

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OF UNIT PALISADE FENCE GAS KIOSK WELFARE/ AMENITY CABIN SWITCH ROOM GEAR DNO CCTV GAS ENGINE TRANSFORMER

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OF UNIT Rev PROJECT CLIENT Size Scale TITLE G A B C D E F WHICH MUST NOT BE DUPLICATED, USED OR DISCLOSED OTHER THIS DOCUMENT IS THE PROPERTY OF CONRAD ENERGY LTD. IT THAN AS EXPRESSLY AUTHORIZED BY CONRAD ENERGY LTD CONTAINS PROPRIETARY AND CONFIDENTIAL INFORMATION 02-10-18 09-10-18 15-10-18 07-11-18 28-11-18 29-04-19 06-09-19 Date Registered in England No. 09866059. office: 71 - 75 Shelton Street, Covent Garden, London, WC2H 9JQ T: +44(0)1865 338166 E: [email protected] W: www.conradenergy.co.uk UNITS D & E, WINDRUSH COURT, BLACKLANDS WAY, ABINGDON OX21 1SY JS JS JS JS JS JS JS OR ITS REPRESENTATIVE By Proposed Site Plan Layout Change Due To New Constrait 1:100 Conrad Energy A1 CONRAD ENERGY LIMITED Hawarden Layout Reorganised Client HV Removed Fence line moved Client HV Added Layout Change Details First Issue Drg. No. © HWN-PSP-01 Apr'd JA JA JA JA JA JA JA Conrad (Hawarden) Limited Report Ref: 01.0009.026 v1 AQ Assessment: Hawarden Power Generation Plant March 2020

APPENDIX A: INPUT DATA

Table A-1 Modelling Inputs

Parameter Modelled Value No. of engines 1 Engine rating (kWe) 2535 Total capacity (MWe) 2.535 NOx concentration (mg/nm3)* 250 CO concentration (mg/nm3) 1100 Exhaust Temp (K) 692.0 Normalised Flow (Nm3/s per engine) 2.64 Actual Flow (Am3/s per engine) 7.24 NOx mass emission (g/s) per engine* 0.66 CO mass emission (g/s) per engine 2.90 Stack Diameter (m) 0.50 Velocity of release (m/s) 36.89 Height of Stack (m) 7.0

[at 5% O2, 0 degC, 1atm, dry] Modelled mass emissions differ from those in the table above for the reasons given in this report, in that they have been adjusted for NOX:NO2 proportion in accordance with EA guidance and also hours of operation in the case of long term emissions. For example: • NOx mass emission per engine = 0.66 g/s; • Multiplied by 0.7 for NOx:NO2 = 0.46 g/s; • Multiplied by (3000 / 8760) hours = 0.158 (modelling input). Table A-2 Stack Location

Stack OS Xm OS Ym Engine 1 333914.2 364886.6

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APPENDIX B: WIND DATA

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APPENDIX C: AIR QUALITY LIMITS

Table C-1 Air Quality Strategy Objectives

Pollutant Concentrations Measured As 200 µg/m3 not to be exceeded 1 hour mean Nitrogen Dioxide (NO2) more than 18 times per year 40 µg/m3 Annual mean 30 µg/m3 Annual mean : Protection of Vegetation Nitrogen Dioxide (NOx) 75 µg/m3 24h: Protection of Vegetation

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APPENDIX D: IMPACT PLOTS

Figure D1: Annual Average NO2 impact

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th Figure D2: 1hr (99.79 percentile) NO2 impact

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Figure D3 24h NO2 impact – ecological features.

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APPENDIX E: ECOLOGICAL SITES

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Magic Map

(c) Crown Copyright and database rights 2020. Ordnance Survey 100022861.

Legend 0 3.5 7

Ramsar Sites (England) km Proposed Ramsar Sites (England) Projection = OSGB36 Ramsar Sites (Wales) xmin = 303400 Special Areas of Conservation (England) ymin = 348900 xmax = 363800 Possible Special Areas of Conservation (England) ymax = 379700 Map produced by MAGIC on 12 March, 2020. Special Areas of Conservation (Wales) Copyright resides with the data suppliers and the map must not be reproduced without their permission. Special Protection Areas (England) Some information in MAGIC is a snapshot of the information that is being maintained or continually updated by the originating organisation. Please refer Potential Special Protection Areas (England) to the metadata for details as information may be illustrative or representative rather than definitive Special Protection Areas (Wales) at this stage. Magic Map

(c) Crown Copyright and database rights 2020. Ordnance Survey 100022861.

Legend 0 1.5 3

Sites of Special Scientific Interest (England) km Sites of Special Scientific Interest (Wales) Projection = OSGB36 xmin = 318500 ymin = 358200 xmax = 348700 ymax = 372800 Map produced by MAGIC on 12 March, 2020. Copyright resides with the data suppliers and the map must not be reproduced without their permission. Some information in MAGIC is a snapshot of the information that is being maintained or continually updated by the originating organisation. Please refer to the metadata for details as information may be illustrative or representative rather than definitive at this stage. Magic Map

(c) Crown Copyright and database rights 2020. Ordnance Survey 100022861.

Legend 0 0.75 1.5 Ancient Woodland (England) km Ancient and Semi-Natural Woodland Ancient Replanted Woodland Projection = OSGB36 xmin = 327500 ymin = 362000 xmax = 340100 ymax = 368100 Map produced by MAGIC on 12 March, 2020. Copyright resides with the data suppliers and the map must not be reproduced without their permission. Some information in MAGIC is a snapshot of the information that is being maintained or continually updated by the originating organisation. Please refer to the metadata for details as information may be illustrative or representative rather than definitive at this stage. CYNGOR CEFN GWLAD CYMRU COUNTRYSIDE COUNCIL FOR WALES

SITE OF SPECIAL SCIENTIFIC INTEREST CITATION

GWYNEDD/DENBIGHSHIRE/ WREXHAM/FLINTSHIRE AFON DYFRDWY (RIVER DEE)

Date of Notification: 1995, 2002

National Grid Reference: SH 930351 – SJ 311695

O.S. Maps 1:50,000 Sheet number: Outdoor Leisure map 18 Explorer maps 255, 256, 257 & 266 1:10,000 Sheet number: SH83 NE; SH84 SE; SH93 NW& NE; SH94 SW; SJ03 NW; SJ04 SW& SE; SJ13 NE, NW, SE & SW; SJ14 SW& SE; SJ23 NW& NE; SJ24 SW& SE; SJ26 NE SJ27 SE; SJ33 NW; SJ34 SW, SE & NE; SJ35 NE; SJ36 NE & NW; SJ44 NW; SJ45 SW& NW

Site area: 1,489.5 ha

Description:

Afon Dyfrdwy (River Dee) is of special interest for its fluvial geomorphology, Carboniferous geology, range of river habitat types, saltmarsh transition habitats, populations of floating water plantain Luronium natans, slender hare’s-ear Bupleurum tenuissimum, sea barley Hordeum marinum, hard-grass Parapholis strigosa, otter Lutra lutra, salmon Salmo salar, bullhead Cottus gobio, brook lamprey Lampetra planeri, river lamprey Lampetra fluviatilis, sea lamprey Petromyzon marinus, club-tailed dragonfly Gomphus vulgatissimus and other aquatic invertebrates.

The main channel of the River Dee lies within both Wales and England, and is notified as two separate SSSIs – the Afon Dyfrdwy (River Dee) SSSI in Wales and the River Dee (England) SSSI in England. The features for which the SSSIs are notified, in particular migratory fish, depend upon the whole river ecosystem. Salmon, otter, club-tailed dragonfly, and fluvial geomorphology are of special interest in both Wales and England.

The site extends from the outflow of Llyn Tegid SSSI downstream to where it flows into the Dee Estuary SSSI. In its swifter upper reaches it flows through the broad valley near , and the spectacular Vale of Llangollen before entering the plain at and meandering northwards through the Cheshire plain to its tidal limit at Farndon. In its slower, more mature reaches the river is characteristic of a floodplain river with meanders, oxbows and other river- formed landscape features. The River Dee is heavily regulated, with its flow controlled by the reservoirs of Tegid, Celyn and Brenig. The site includes the Ceiriog, Meloch, Tryweryn, and Mynach tributaries.

The source of the River Dee lies within the National Park and its catchment contains a wide spectrum of landscapes from high mountains around Bala, rugged peaks near Llangollen, steep-sided wooded valleys, and the plains of Cheshire and north Shropshire through to the vast mudflats of the estuary. There is a tidal influence as far upstream as Farndon and high tides regularly exceed the weir crest level.

The course and topography of the River Dee and its tributaries were strongly influenced and modified during the last Ice Age. The underlying geology of the Dee ranges from impermeable Cambrian and Ordovician shales in the west, through Silurian to Carboniferous Limestone outcrop at Llangollen to Coal Measures and thick boulder clay overlying the Triassic sandstones of the Lower Dee valley.

GEOLOGY/GEOMORPHOLOGY

Three separate Geological Conservation Review (GCR) Sites are located within the Afon Dyfrdwy (River Dee) SSSI. The River Dee (Rhewl Section) and River Dee (Holt to Worthenbury) GCR sites were selected for their fluvial geomorphological importance and had previously been notified as individual SSSI. The rocks exposed at Dee Bridge are important for their Upper Carboniferous stratigraphy.

Dee Bridge (Upper Carboniferous) Dee Bridge is important for its Upper Carboniferous stratigraphy. It encompasses the type locality for the Dee Bridge Formation. Adjacent to the river is a sequence of shales, sandstones and mudstones deposited under fluvio-deltaic conditions between the Kinderscoutian and Langsettian stages. Along with a correlative site 20 km to the north (Ruby Brickworks), it comprises the most complete documented sequence of upper Namurian strata in North Wales, illustrating the variation of marginal facies along the northern margin of the Wales-Brabant massif. The site is unique in Wales in showing the progressive, increased influence of more northerly-derived sediments over those derived from the northern margin of the Wales-Brabant massif.

River Dee (Holt to Worthenbury) (fluvial geomorphology) This site comprises a meandering reach of the River Dee between Holt in the north and Worthenbury in the south. It includes land in Wrexham (Wales) and Cheshire (England) and consists of some of the most spectacular and intricately developed river bends or meanders seen anywhere in Britain. The site is important for studies of fluvial geomorphology.

The GCR site was selected for: 1) the present river channel and its intricate pattern of meanders; 2) the main areas of floodplain either side of the river, for the full length of the selected reach; 3) all the visible palaeochannels (abandoned channels) located on the floodplain adjacent to the present channel; 4) the gravel and sand bars located within the modern channel and the other evidence of modern-day river processes contained within the channel; and 5) the most impressive of the remnants of ancient river cliffs located towards the north-east and south-west margins of the site.

The pattern and scale of the meanders are exceptional on a British scale: the range of forms from simple curves to double-headed forms, and the intricacy of the pattern developed over the whole reach is outstanding. The total landform assemblage, including the remnants of ancient river cliffs, the floodplain areas, and the present and abandoned channels, provides the basis for reconstructing the development of the river since the end of the last glaciation. The abandoned channels and old meander loops (some of which were once oxbow lakes) are exceptional landforms in their own right; their pattern, location and contained sediments provide significant potential for reconstructing some of the geologically recent changes in the course of the River Dee in its long evolution during Holocene times, namely the last 11,500 years. The gravel and sand bars distributed along the course of the modern channel, and the changing form of its banks and bed, bear witness to a range of important modern-day fluvial processes.

Although this part of the course of the River Dee has changed in position markedly during the Holocene, the last few hundred years have been characterised by relative channel stability. It seems likely that the banks and bed of the modern channel are now evolving in response to changing flow and sediment regimes induced by upstream regulation and other human modification to the fluvial system. The significance of the site for studying modern-day river processes is enhanced by the tidally-influenced downstream reach. This renders the site potentially significant for investigating the effects of possible future sea-level rise on the development of the river channel, particularly in view of the long history of tidal influences and stage records (river level) at downstream locations.

This reach of the Dee is a valuable part of the heritage of Great Britain, due to its outstanding combination of landform, sedimentary and process evidence. Most large British rivers have been significantly channelised or straightened in their lower reaches. The Dee is exceptional in maintaining an extremely sinuous platform across the sensitive fluvial-tidal transition zone.

River Dee (Rhewl Section) (fluvial geomorphology) This reach of the River Dee provides a particularly good example of ingrown incised meanders. Their formation has involved lateral erosion as well as vertical erosion, so that the valley is asymmetrical in cross-profile and indicates that rejuvenation was progressive. In this respect the Dee meanders provide a geomorphological contrast to the entrenched meanders of the River Wye.

FLORA

The River Dee below Llyn Tegid is a predominantly mesotrophic river with a diversity of vegetation types reflecting its geology and geographical location. Near the outflow of Llyn Tegid, the community is typical of a sandstone, mudstone and hard limestone river type intergrading with a mesotrophic river type dominated by gravels, pebbles and cobbles. Species such as hemlock water-dropwort Oenanthe crocata, alternate water-milfoil Myriophyllum alterniflorum, intermediate water-starwort Callitriche hamulata, water mosses Fontinalis antipyretica and F. squamosa, and reed canary-grass Phalaris arundinacea are present. In spite of the large size of the river, the moderate gradient allows pond water-crowfoot Ranunculus peltatus to dominate. The nationally and internationally rare floating water-plantain Luronium natans also occurs here.

Below Corwen the river increases in gradient such that the community changes to an oligo- mesotrophic river type comprised of numerous bryophytes including Brachythecium rivulare, Conocephalum conicum, Eurynchium praelongum, Philonotis fontana and Rhyncostegium riparioides, interspersed with patches of Fontinalis spp. and sparse milfoil and crowfoot.

Between Llangollen and Bangor-on-Dee, sandstone, mudstone and hard limestone river type vegetation again predominates, this time with the unusual hybrid crowfoot Ranunculus x bachii (R. fluitans x aquatilis) occurring in large stands. The Dee is one of only two known UK localities for this hybrid. In this section the river shows signs of nutrient enrichment with the introduced Canadian waterweed Elodea canadensis becoming more prevalent.

Below Bangor-on-Dee the River Dee flows into the Cheshire plains and displays typical characteristics of lowland river types with shallow gradients flowing over nutrient rich soils, with pondweeds such as curled pondweed Potamogeton crispus, perfoliate pondweed Potamogeton perfoliatus and small pondweed Potamogeton berchtoldii occurring frequently. Tripartite bur-marigold Bidens tripartita and lesser pondweed Potamogeton pusillus, both rare along Welsh rivers, are found in this section. This section is a lowland, clay-dominated river type but due to overgrazing of the margins and eutrophication this vegetation component is threatened and frequently species-poor. Fennel pondweed Potamogeton pectinatus also occurs here and in the more eutrophic sections may be the only submerged species.

There is good tree cover along the banks of the River Dee and the tributaries, with the Ceiriog being tree lined on both banks along much of its length. The dominant species are alder Alnus glutinosa and willow Salix spp., with occasional ash Fraxinus excelsior and oak Quercus spp.. Where sections of the riverbank have been fenced off the vegetation tends to be dominated by bramble Rubus fruticosus, nettles Urtica diocia and other tall ruderals. Indian (also known as Himalayan) balsam Impatiens glandulifera and Japanese knotweed Fallopia japonica are increasing throughout the site.

Downstream of Chester along the canalised section of the river towards the estuary saltmarsh transition habitats have developed. These comprise upper and middle saltmarsh, annual high marsh and wet neutral grassland. These habitats support such rarities as the following species of special interest: slender hare’s-ear, sea barley and hard-grass.

MAMMALS

The otter is of special interest and is found throughout the site, especially where appropriate bank side cover exists to provide secure holts and lying up areas. Water vole Arvicola terrestris have been recorded on the middle and lower reaches of the River Dee.

FISH

The River Dee is is of special interest for Atlantic salmon for which it is one of the Environment Agency’s index rivers. The Mynach, Meloch and Ceiriog tributaries are the most important salmon spawning tributaries in the Dee catchment and are included within this SSSI. Other migratory fish utilising the system include river lamprey, sea lamprey, sea trout Salmo trutta trutta, and eel Anguilla anguilla. Smelt Osmerus eperlanus and Twaite shad Alosa fallax have been recorded in the section between Chester and the estuary, but are not thought to have breeding populations.

The Dee also supports populations of non-migratory fish including bullhead and brook lamprey which are species of special interest, as well as brown trout Salmo trutta. The river is noted for its grayling Thymallus thymallus. The middle and lower reaches of the Dee support a diverse coarse fish population including, roach Rutilus rutilus, dace Leuciscus leuciscus, bream Abramis brama and perch Perca fluviatilis, although low water temperatures and poor riparian habitat limit spawning success. Several coarse fish species including Barbel Barbus barbus, ruffe Gymnocephalus cernua, chub Leuciscus cephalus, and silver bream Blicca bjoerkna have been introduced to the system.

INVERTEBRATES

The lower reaches of the River Dee support Britain’s only known population of the stonefly Isogenus nubecula. Club-tailed dragonfly Gomphus vulgatissimus is nationally scarce and present along the lower Dee, particularly where the river is slow flowing and there is adjacent woodland habitat or bankside tree cover available for adults. The nationally scarce weevil Baris lepidii has been recorded at its only Welsh site on sandy riverbanks along the lower Dee. All three species are of special interest.

Other aquatic invertebrates present include the nationally scarce freshwater pearl mussel Margaritifera margaritifera which is recorded from only nine Welsh rivers, and the water beetle Bidessus minutissimus, which inhabits reaches of the middle Dee, where it prefers fine gravel substrates in shallow, slow flowing side-waters.

Remarks:

The section of the Dee that flows through England is notified as a separate SSSI under the name of River Dee (England), ensuring that the whole of the river is safeguarded.

Part of the SSSI lies within the Snowdonia National Park.

The Afon Dyfrdwy (River Dee) SSSI supports the following habitats and species listed in the EC Habitats Directive (Directive 92/43/EEC on the Conservation of Natural Habitats and of Wild Fauna and Flora):

Rivers with floating vegetation often dominated by water crowfoot - Annex I Otter – Annex II & IV Sea lamprey – Annex II River lamprey – Annex II & V Brook lamprey – Annex II Atlantic salmon – Annex II & V Bullhead – Annex II Freshwater pearl mussel – Annex II & V Grayling – Annex V

The otter and the freshwater pearl mussel are listed under Schedule 5 of the Wildlife and Countryside Act 1981 (as amended).

This document is NOT a definitive legal version and has been formatted, updated and partially edited for use on the CCW Web site. This document should not be used in any legal proceedings, public enquiry or any other hearing or appeal. If you require a full legal copy of the document please contact CCW in writing.

CYNGOR CEFN GWLAD CYMRU COUNTRYSIDE COUNCIL FOR WALES

SITES OF SPECIAL SCIENTIFIC INTEREST CITATION

FLINTSHIRE BUCKLEY CLAYPITS AND COMMONS

Date of Notification: 2002

National Grid References: SJ 2725 6504 SJ 2893 6532 SJ 2910 6407 SJ 2858 6504 SJ 2778 6589 SJ 2819 6556

O.S. Maps: 1:50,000 Sheet Number: 117 1:10,000 Sheet Number: SJ26SE & SJ26NE

Site Area: 99.7 ha

Description:

Buckley Claypits and Commons is a composite site located around the northern and eastern boundaries of the town of Buckley, at an altitude of between 100 and 140 m. It is of special interest for its population of the great crested newt Triturus cristatus, its assemblage of widespread amphibian species, and for its mosaic of semi-natural grassland.

The solid geology of the site consists of deposits of Carboniferous Middle Coal Measures. These include siltstone, mudstone, sandstone, fireclay and coal. The clay and coal mineral deposits have been commercially exploited. These are in part overlain by glacial boulder clay. Soils are predominantly loamy to clayey and slowly permeable.

Water bodies at Buckley Claypits and Commons support one of the largest breeding populations of the great crested newt Triturus cristatus in Great Britain. Torch night counts undertaken during the spring have revealed over 100 adult and sub-adult animals on several occasions. Great Britain is considered to support one of the strongholds for this species in Western Europe. These water bodies also support significant populations of other widespread amphibian species including smooth newt Triturus vulgaris, palmate newt T. helveticus, common frog Rana temporaria and common toad Bufo bufo. Many of these water bodies have been created by past mineral exploitation. Others have been created for stock watering purposes whilst more recently they have been created specifically to conserve the amphibian populations.

Surrounding areas of land support a mosaic of habitats including dry and wet semi-improved and improved grasslands, lowland dry and wet heath, tall herb, bracken, scrub and secondary woodland. Lowland dry and wet heath are an uncommon habitat type in North East Wales. This mosaic of habitats forms an important foraging, sheltering and overwintering area for adult and juvenile amphibians.

Buckley Lower and Middle Commons are also of special interest for their vegetation, supporting a mosaic of communities including acidic, neutral and marshy grassland, wet heath, scrub and broadleaved woodland. Freely draining areas support herb-rich neutral and acid grasslands, while flushed slopes and damper depressions support rush Juncus spp. and purple moor-grass Molinia caerulea dominated marshy grassland. The herb-rich grassland is widespread across the site and dominated by crested dog’s-tail Cynosurus cristatus, common bent Agrostis capillaris, sweet vernal grass Anthoxanthum odoratum and red fescue Festuca rubra, with yarrow Achillea millefolium, black knapweed Centaurea nigra, common bird’s- foot-trefoil Lotus corniculatus, meadow vetchling Lathyrus pratensis, meadow buttercup Ranunculus acris, and creeping cinquefoil Potentilla reptans. The acid grassland is characterised by common bent A. capillaris, sheep’s fescue F.ovina, heath grass Danthonia decumbens, mat-grass Nardus stricta, with devil’s bit scabious Succia pratensis, sneezewort Achillea ptarmica, and lousewort Pedicularis sylvatica. The rush pasture is dominated either by sharp-flowered rush Juncus acutiflorus or soft rush J. effusus with associated species marsh bedstraw Galium palustre, greater bird’s-foot-trefoil Lotus uliginosus, and lesser spearwort Ranunculus flammula. Other damp areas are dominated by purple moor-grass with tormentil Potentilla erecta, Yorkshire fog Holcus lanatus, velvet bent Agrostis canina, heath wood-rush Luzula multiflora and green-ribbed sedge Carex binervis. Locally heather Calluna vulgaris may be present. A small area of wet heath is characterised by cross-leaved heath Erica tetralix and bog-moss Sphagnum compactum is also present. The acid and herb-rich grasslands support populations of petty whin Genista anglica, while the rush mires support western marsh-orchid Dactylorhiza majalis ssp. purpurella. Both of these species are uncommon in North East Wales.

The ecological interest of the site is enhanced by the presence of breeding reed bunting, Emberiza schoeniclus and water vole Arvicola terrestris.

Remarks:

1. The former Etna tip is managed by Flintshire County Council as a Country Park.

2. The great crested newt Triturus cristatus is protected under the provisions of the Wildlife and Countryside Act 1981 (as amended) and the EC Habitats Directive (Directive 92/43/EEC on the Conservation of Natural Habitats and of Wild Fauna and Flora (as implemented in Great Britain by Statutory Instrument 2716: The Conservation (Natural Habitats & c.) Regulations 1994)).

3. The site supports biodiversity Priority species such as great crested newt Triturus cristatus, reed bunting Emberiza schoeniclus and water vole Arvicola terrestris.

4. Part of the site is registered urban common.

5. The site forms part of the Deeside and Buckley Newt Sites Special Area of Conservation (SAC).

CYNGOR CEFN GWLAD CYMRU COUNTRYSIDE COUNCIL FOR WALES

SITE OF SPECIAL SCIENTIFIC INTEREST CITATION

FLINTSHIRE CONNAH’S QUAY PONDS AND WOODLANDS

Date of Notification: 2001

National Grid Reference: SJ290676 SJ283684

O.S. Maps: 1:50,000 Sheet Number: 117 1:10,000 Sheet Number: SJ26NE

Site Area: 94 ha

Description:

Connah’s Quay Ponds and Woodlands is a composite site located on the coastal slopes of the Dee Estuary. At an altitude of between 50-80 m, it overlooks the adjacent conurbation of Connah’s Quay. The site is of special interest for its population of great crested newt Triturus cristatus, its assemblage of widespread amphibian species, and for its semi-natural broadleaved woodland.

Upper Carboniferous sandstones with overlying glacial deposits shape the overall character of the landscape. During the 18th and 19th centuries scattered extraction of coal, clay and sand took place, but since then the area has predominantly been used for agriculture and more recently informal recreation. Much of the site lies within the incised Wepre Brook valley.

Wepre and Broadoak woodlands support a large stand of semi-natural broadleaved woodland which is composed predominantly of oak Quercus spp. and ash Fraxinus excelsior, with sycamore Acer pseudoplatanus, birch Betula pendula and alder Alnus glutinosa locally prominent. Parts of the woodland have been replanted with introduced species such as beech Fagus sylvatica and larch Larix spp. There is a distinct but usually sparse shrub layer typically composed of hazel Corylus avellana with occasional holly Ilex aquifolium, wych elm Ulmus glabra and hawthorn Crataegus monogyna. The field layer is dominated by ivy Hedera helix, bramble Rubus fruticosus, honeysuckle Lonicera periclymenum, broad buckler fern Dryopteris dilatata and male fern Dryopteris filix-mas. However, in a few areas great wood-rush Luzula sylvatica and bluebell Hyacinthoides non-scripta are locally abundant. A combination of acidic, basic and wet conditions add to the overall diversity.

The great crested newt Triturus cristatus has suffered a marked decline throughout Great Britain and Continental Europe as a result of habitat loss. Great Britain is considered to be one of the strongholds for this species in Western Europe. Water bodies within the site in total support one of the largest known breeding populations of the great crested newt in Great Britain. The site also supports significant populations of the commoner amphibian species notably smooth newt Triturus vulgaris, palmate newt T.helveticus, common frog Rana temporaria and common toad Bufo bufo. The majority of these water bodies were created for agricultural and nature conservation purposes.

Surrounding areas of land support a mosaic of ancient and secondary broadleaved woodland, scrub, grassland, and tall ruderal vegetation. These habitats form important foraging and over wintering areas for adult and juvenile amphibians.

The ecological interest of the site is enhanced by the presence of several social groups of badger Meles meles, a population of bullhead Cottus gobio within the Wepre Brook, a tributary of the River Dee; and a rich and diverse woodland fungal flora.

Remarks:

The great crested newt Triturus cristatus is protected under the provisions of the Wildlife and Countryside Act 1981 (as amended) and the EC Habitats and Species Directive (as implemented in Great Britain by Statutory Instrument 2716: The Conservation (Natural Habitats & c.) Regulations 1994).

Gathering Grounds Wood and Llwyni Pond have been designated by Flintshire County Council as a Local Nature Reserve.

Wepre Park is managed by the Flintshire County Council Countryside Service as a Country Park.

Broadoak Wood is managed by the Deeside Urban Wildlife Group as a nature reserve.

The great crested newt Triturus cristatus is listed in the UK’s Biodiversity Action Plan as a Priority Species.

This document is NOT a definitive legal version and has been formatted, updated and partially edited for use on the CCW Web site. This document should not be used in any legal proceedings, public enquiry or any other hearing or appeal. If you require a full legal copy of the document please contact CCW in writing.

CYNGOR CEFN GWLAD CYMRU COUNTRYSIDE COUNCIL FOR WALES

SITE OF SPECIAL SCIENTIFIC INTEREST CITATION

FLINTSHIRE / DENBIGHSHIRE DEE ESTUARY/ABER AFON DYFRDWY

Date of Notification: 1954, 1971, 1979, 1983, 1984, 1998

National Grid Reference: SJ 220 800

O.S. Maps: 1:50,000 Sheet Number: 108, 116, 117 1:10,000 Sheet Number: SJ08SE, SJ27NE, NW, SE, SW SJ17NE, SJ28NW, SE, SW SJ18NE, NW, SE, SW SJ36NW, SJ26NE, SJ37SW

Site Area: 13,679.7 ha Area in Wales: 8,442.6 ha Area in England: 5,237.1 ha

Description:

The Dee Estuary/Aber Afon Dyfrdwy is of special interest for its total populations of internationally important wintering waterfowl; its populations of individual waterfowl and tern species whose numbers reach national and in some cases, internationally important levels; its intertidal mud and sandflats, saltmarsh and transitional habitats; the hard rocky sandstone cliffs of Hilbre Island and Middle Eye with their cliff vegetation and maritime heathland and grassland; its assemblage of nationally scarce plants; and its populations of sandhill rustic moth Luperina nickerlii gueneei, a Red Data Book species.

The Dee is a large funnel shaped estuary which lies between the , England and Flintshire, North East Wales. It was formerly much more extensive but large scale reclamation of intertidal land has occurred, principally at the head of the estuary. This followed the canalisation of the River Dee in the eighteenth century when an attempt was made to secure the continuation of Chester as a port. The estuary contains extensive areas of intertidal sand and mudflats which support a variable but characteristic benthic fauna depending on the nature of the substrate. Large areas of saltmarsh also occur at its head and along part of its north-eastern shore. The estuary continues to accrete and further saltmarshes are developing, particularly on the English shoreline. Locally, on the Welsh shoreline, saltmarsh continues to erode, particularly between Greenfield and Flint. Within the estuary, the three small sandstone islands of Hilbre, Middle and Little Eye provide the only hard natural rock coast habitat along this section of coastline. A largely unvegetated shingle ridge occurs at the . Although yellow embryo dunes occur at its western end, these are susceptible to erosion from wave action.

The Dee Estuary/Aber Afon Dyfrdwy is one of the most important estuaries in Britain and amongst the most important in Europe for its populations of waders and wildfowl. The estuary is particularly important for its wintering bird populations and both waders and wildfowl achieve numbers of international importance. The estuary supports internationally important populations of a number of wader species, namely, oystercatcher Haematopus ostralegus, knot Calidris canutus, curlew Numenius arquata, redshank Tringa totanus, bar-tailed godwit Limosa lapponica, black-tailed godwit Limosa limosa, grey plover Pluvialis squatarola and dunlin Calidris alpina. The waders utilise the abundant invertebrate populations principally on the extensive intertidal flats, particularly the mudflats. Several wading bird species also make extensive use of the coastal grazing marshes and fields adjoining the estuary for feeding and roosting. Around the estuary are a number of high tide roost sites; principal sites include the Hilbre Islands, the foreshore at , the shingle spit at Point of Ayr and the saltmarshes at . Wildfowl present in internationally important numbers include pintail Anas acuta, for which the Dee and Mersey have been the principal British wintering estuaries for many years, teal Anas crecca and shelduck Tadorna tadorna, whilst wigeon Anas penelope occur in nationally important numbers.

The Dee Estuary/Aber Afon Dyfrdwy is also an important staging post for migrating birds during both spring and autumn. Nationally important numbers of ringed plover Charadrius hiaticula are regularly seen on passage. In addition the summering flock of non-breeding black-tailed godwit, one of the largest in the , is regarded as of national importance.

The Dee Estuary/Aber Afon Dyfrdwy also supports nationally important numbers of feeding common tern Sterna hirundo. These birds historically nested on the Burton Marshes where they were frequently inundated by spring tides. They now nest on specially developed habitats on lagoons within the Shotton Steelworks complex outside the site. The large breeding population of redshank, which utilise the ungrazed and lightly grazed saltmarshes for nesting, is regarded as of national significance.

The Dee Estuary/Aber Afon Dyfrdwy also supports nationally important flocks of cormorant Phalacrocorax carbo, which occur throughout the year and great crested grebe Podiceps cristatus, peak numbers of which occur in the autumn during the moult.

The Dee Estuary/Aber Afon Dyfrdwy supports extensive areas of saltmarsh vegetation and exhibits a complete succession from early pioneer vegetation colonising intertidal flats through lower, middle and upper saltmarsh types to brackish and freshwater transitions at the top of the shore. Although land reclamation has led to a loss of many of these natural transitions, there are still a number of areas, particularly on the English shoreline, around Neston and Parkgate, where transitions to swamp vegetation still occur. These are dominated usually by common reed Phragmites australis and sea club-rush Bolboschoenus maritimus. On the Welsh shoreline this habitat feature is limited to areas around Connah’s Quay and to the south east of Flint. In North East Wales, swamp vegetation is scarce generally and the more extensive areas adjacent to the estuary, including those at Shotton, are therefore important.

The saltmarshes themselves support a variety of vegetation communities characteristic of estuaries in northern and western Britain. The Dee Estuary/Aber Afon Dyfrdwy supports a large area of marsh dominated by common cord grass Spartina anglica. Its current extent reflects the fact that the estuary continues to accrete following historical land claim. Species such as glasswort Salicornia sp. and annual seablite Suaeda maritima are also present. Much of the saltmarsh remains ungrazed and this has allowed extensive stands of species intolerant of grazing to develop, such as sea purslane Atriplex portulacoides. Where grazing intensity has declined in locations at the top of the shore, rank strandline vegetation dominated by common couch Elytrigia repens and sea couch Elytrigia atherica has developed.

Of particular note within the reclaimed land on the Ministry of Defence ranges adjacent to the estuary, is saltmarsh characterised by saltmarsh flat-sedge Blysmus rufus, a species close to its southern limit in North Wales. Although the saltmarshes are generally species poor, the nationally scarce species, slender hare’s-ear Bupleurum tenuissimum is found at Connah’s Quay, at its northern British limit of occurrence.

The three sandstone islands which comprise the Hilbre Island complex represent the only natural hard rock coast within the estuary and are the only examples of this habitat between the limestone cliffs of the Creuddyn Peninsula and the sandstone cliffs of St Bee’s Head in Cumbria. Consequently, the coastal cliffs and the maritime heathland and grassland on the plateau areas above the cliffs represent the only regional examples of these vegetation types. Although the western Hilbre cliffs are too exposed to support vegetation, the sheltered eastern cliffs support common scurvy grass Cochlearia officinalis and sea campion Silene uniflora. The nationally scarce rock sea lavender Limonium britannicum occurs together with the regionally scarce sea spleenwort Asplenium marinum.

The Dee Estuary/Aber Afon Dyfrdwy supports a number of other nationally scarce higher plants in addition to those previously mentioned including Portland spurge Euphorbia portlandica at Point of Ayr, white horehound Marrubium vulgare in coastal grazing fields at Point of Ayr and white mullein Verbascum lychnitis on basic slag waste at Flint.

The Red Data Book species, sandhill rustic moth Luperina nickerlii gueneei occurs within the estuary towards its mouth on both the English and Welsh shorelines.

The presence of a large herd of grey seal Halichoerus grypus, is considered to be of regional interest. These haul out on West Hoyle Bank, though breed elsewhere. The presence of breeding reed warblers Acrocephalus scirpaceus, a scarce species in North Wales, in reedbeds in and adjacent to the estuary, is of interest. The presence of the uncommon anadromous fish, smelt Osmerus eperlanus, is also of note.

Remarks:

The Dee Estuary has been designated as a Ramsar Site under the Ramsar Convention of Wetlands of International Importance and as a Special Protection Area (SPA) under the EC Birds Directive (79/409) in July 1985.

A number of nature reserves are managed within the site.

This document is NOT a definitive legal version and has been formatted, updated and partially edited for use on the CCW Web site. This document should not be used in any legal proceedings, public enquiry or any other hearing or appeal. If you require a full legal copy of the document please contact CCW in writing.

CYNGOR CEFN GWLAD CYMRU COUNTRYSIDE COUNCIL FOR WALES

SITES OF SPECIAL SCIENTIFIC INTEREST CITATION

FLINTSHIRE MAES Y GRUG

Date of Notification: 1997

National Grid Reference: SJ263664

O.S. Maps: 1:50,000 Sheet Number: 117 1:10,000 Sheet Number: SJ26NE

Site Area: 17.4 ha

Description:

Maes y Grug is situated near approximately 3 km north east of Mold, at an altitude of 120 m above mean sea level. The site is of special interest for its large population of the great crested newt Triturus cristatus. This species has suffered a marked decline throughout Great Britain and continental Europe as a result of habitat loss and pollution. Great Britain is one of the strongholds of this species in western Europe.

The geology of the site is Middle Coal Measures (Carboniferous Period), with drift deposits of boulder clay on the surface. The site has been subject to historic coal extraction by deep mining and in 1991 was subject to open casting coal mining. Following coal extraction, the land was restored for nature conservation and agriculture including the creation of water bodies and associated wetland features for the benefit of wildlife.

The water bodies at Maes y Grug support one of the largest known populations of the great crested newt in north east Wales. Torch night counts undertaken during the spring have revealed over 200 animals on several occasions. Populations of the commoner amphibian species notably smooth newt Triturus vulgaris, palmate newt T. helveticus, common frog Rana temporaia and common toad Bufo bufo are also present.

The mosaic of grassland, scrub and woodland habitats surrounding the water bodies have been managed or allowed to develop naturally. These habitats collectively form important foraging and over wintering areas for adult and juvenile amphibians.

Remarks:

The great crested newt Triturus cristatus is protected under the provisions of the Wildlife and Countryside Act 1981 (as amended) and the EC Habitats and Species Directive.

The great crested newt Triturus cristatus is listed in the UK Biodiversity Action Plan.

This document is NOT a definitive legal version and has been formatted, updated and partially edited for use on the CCW Web site. This document should not be used in any legal proceedings, public enquiry or any other hearing or appeal. If you require a full legal copy of the document please contact CCW in writing.

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