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2565-01 / Proposed Extension to the Allington IWMF PEIR Main Report July 2020 11-i

CHAPTER 11.0 ECOLOGY AND NATURE CONSERVATION

11.0 ECOLOGY AND NATURE CONSERVATION ..................................................... 11-1

11.1 Introduction .......................................................................................................... 11-1

11.2 Methodology ........................................................................................................ 11-2

11.3 Baseline ............................................................................................................. 11-17

11.4 Assessment of Effects ....................................................................................... 11-29

11.5 Cumulative Effects ............................................................................................. 11-42

11.6 Mitigation ........................................................................................................... 11-45

11.7 Residual Effects and Conclusions ...................................................................... 11-46

APPENDICES (bound separately in Volume 3)

Appendix 11-1 ..................................................................... Preliminary Ecological Appraisal

Appendix 11-2 .......... Extended Phase 1 / UKHC Habitat Survey, and calculation of baseline

............................ ecological value in accordance with Biodiversity Metric 2.0;

Appendix 11-3 ......................................................................................... Invertebrate Survey

Appendix 11-4 ........................................................................ Reptile and Amphibian Survey

Appendix 11-5 ...................................................................................... Breeding Bird Survey

Appendix 11-6 ...................................................................................................... Bat Survey

Appendix 11-6 ............................ Assessment of Sensitivity of North Downs Woodlands SAC

Appendix 11-8 ..................................................................................................... HRA Report

Appendix 11-9 ................................................................................Stangate Baseline Report

Appendix 11-10 ........................ Stangate Ecological Enhancement Scheme - East and West

Appendix 11-11 ........................................ Stangate Ecological Enhancement Scheme - East

Appendix 11-12 ................................................................ Biodiversity Metric without HWRC

Appendix 11-13: .......................................... Biodiversity Metric 2.0 Calculation – with HWRC

Please note that a full list of acronyms is provided the contents to this PEIR and should be

referred to when reading this Chapter.

2565-01 / Proposed Extension to the Allington IWMF PEIR Main Report July 2020 11-1

11.0 ECOLOGY AND NATURE CONSERVATION

11.1 Introduction

Structure of Chapter

11.1.1 This Chapter considers the impacts of the Proposed Extension on flora and fauna,

in accordance with the requirements of the Infrastructure Planning (Environmental

Impact Assessment) Regulations 2017.

11.1.2 The legislative and policy context against which the Proposed Extension should be

considered is summarised below, followed by a summary of the consultation

responses that have been received prior to the preparation of this Chapter,

together with details of how they have been taken into consideration in the

preparation of this assessment. This is then followed by confirmation of the

reasonable worst-case parameters that have been used in the assessment of

effects. The Chapter then describes the background, scope and methodology of

the assessment; this is then followed by a description of habitats and fauna present

on the Site, including the occurrence of legally protected species, and invasive

alien species. The nature conservation interest of the Site and its surroundings is

then evaluated; any significant impacts upon interest features are assessed,

including indirect impacts on designated sites in the wider vicinity of the Proposed

Extension. Proposed mitigation and ecological enhancement measures are

outlined, with a summary of residual impacts following the implementation of

mitigation measures.

11.1.3 The Chapter is informed by the following ecological surveys and reports, which are

presented as Technical Appendices:

• Preliminary Ecological Appraisal (PEA), incorporating a data search to provide

contextual information (Appendix 11-1);

• Extended Phase 1 / UKHC Habitat Survey, and calculation of baseline

ecological value in accordance with Natural England’s Biodiversity Metric 2.0

(BM 2.0) (Appendix 11-2);

• Invertebrate Survey (Appendix 11-3);

• Reptile and Amphibian Survey (Appendix 11-4);

• Breeding Bird Survey (Appendix 11-5);


• Bat Survey (Appendix 11-6);

• Assessment of sensitivity of North Downs Woodlands SAC (Appendix 11-7);

• HRA Report (Appendix 11-8);

• Stangate Baseline Report (Appendix 11-9);

• Stangate Ecological Enhancement Scheme – East and West (Appendix 11-

10);

• Stangate Ecological Enhancement Scheme - East (Appendix 11-11);

• Biodiversity Metric without HWRC (Appendix 11-12); and

• Biodiversity Metric 2.0 Calculation – with HWRC (Appendix 11-13).

Competence

11.1.4 This Chapter has been compiled by Kevin Barry Honour MSc MCIEEM, a Director

of Argus Ecology Ltd., who has over 27 years’ experience of ecological impact

assessment; this includes extensive experience of the assessment of energy

recovery and related facilities, including the ecological assessment of air quality

effects.

11.1.5 Argus Ecology Ltd. are a specialist ecological consultancy, established in 1991.

Employee expertise includes protected species survey and mitigation, habitat and

ornithological surveys. All ecological staff are Full Members of the Chartered

Institute of Ecology and Environmental Management (CIEEM).

11.2 Legislation, Policy and Guidance

European Conservation Legislation, Policy and Guidance

11.2.1 The Habitats Directive (92/43/EEC) provides for the establishment of protected

sites (Special Areas of Conservation (SAC)) as part of the Natura 2000 network, to

protect habitats and species of Community interest listed on Annex I and Annex II

respectively of the Directive. It also provides for strict protection of species of

Community interest listed in Annex IV(a) of the Directive (‘European Protected

Species’).

11.2.2 Article 6 (3) of the Habitats Directive provides for the protection of designated sites,

stating: “Any plan or project not directly connected with or necessary to the


management of the site but likely to have a significant effect thereon, either

individually or in combination with other plans or projects, shall be subject to

appropriate assessment of its implications for the site in view of the site’s

conservation objectives. In the light of the conclusions of the assessment of the

implications for the site and subject to the provisions of paragraph 4, the competent

national authorities shall agree to the plan or project only after having ascertained

that it will not adversely affect the integrity of the site concerned and, if appropriate,

after having obtained the opinion of the general public.”

11.2.3 Article 12 of the Habitats Directive sets out the system of strict protection which

Member States are required to adopt for animal species listed on Annex IV(a).

Article 12(1)(b) prohibits: “deliberate disturbance of these species, particularly

during the period of breeding, rearing, hibernation and migration’; Article 12(1)(d)

prohibits ‘deterioration or destruction of breeding sites or resting places.”

11.2.4 Council Directive 2009/147/EC on the conservation of wild birds (the ‘Birds

Directive’) provides for the conservation and management of all wild bird species

naturally occurring in the European Union, their nests, eggs and habitats.

11.2.5 Article 2 of the Birds Directive provides for the maintenance of populations of wild

birds: “at a level which corresponds in particular to ecological, scientific and cultural

requirements, while taking account of economic and recreational requirements, or

to adapt the population of these species to that level.” Article 4(4) requires that

(outside of protected sites) member states: “should strive to avoid pollution or

deterioration of habitats.”

11.2.6 The Habitats and Birds Directives are implemented in England and Wales by the

Conservation of Habitats and Species Regulations 2017 (the ‘Habitats

Regulations’). Regulation 10 implements provisions in Article 4 of the Birds

Directive, requiring competent authorities to: “use all reasonable endeavours” to

“avoid any pollution or deterioration of habitats of wild birds.” Regulation 42

implements the system of strict protection applied to European Protected Species.

Regulation 63 addresses the requirements to undertake an appropriate

assessment of plans or projects which have a likely significant effect on European

conservation sites.


11.2.7 The Conservation of Habitats and Species (Amendment) (EU Exit) Regulations

2019 were designed to enable the UK to continue to meet its international

commitments, such as the Berne and Bonn conventions, and ensure that

regulations transposing the EU Habitats and Wild Birds Directives are operable, by

making amendments to the Habitats Regulations and other instruments which

transpose the Directives into UK law. The purpose of the Directive was not to

introduce any changes to the level of site protection derived from EU law, or to

change the assessment process.

National Conservation Legislation, Policy and Guidance

11.2.8 The Wildlife and Countryside Act 1981 (as amended) provides the principal

legislation for designation of nationally important conservation sites and the

protection of species. Section 28 provides powers for the designation of Sites of

Special Scientific Interest (SSSIs), while subsequent amendments, including those

enacted by the Countryside and Rights of Way Act 2000 and the Natural

Environment and Rural Communities Act 2006, strengthen the protection of SSSIs.

11.2.9 Section 40 of the Natural Environment and Rural Communities Act 2006 (‘NERC

Act’) sets out the duty of public authorities to conserve biodiversity in the exercise

of their functions, through “having regard, so far as is consistent with the proper

exercise of their duties, to the purpose of conserving biodiversity”. Biodiversity

conservation is further defined as including the restoration or enhancement of a

population or habitat. Section 41 of the NERC Act requires the Secretary of State to

publish a list of species and habitats which are of principal importance for the

conservation of biodiversity in England (i.e. ‘priority species and habitats’), and to

take and promote the taking of “reasonably practicable” steps to further their

conservation.

11.2.10 As outlined in Chapter 3, the relevant NPS’s provide the primary basis for decisions

by the SoS on development consent applications for NSIPs. The requirements of

the NPS’s of most relevance to this Chapter of the PEIR are summarised below:

NPS EN-1, Overarching National Policy Statement for Energy

11.2.11 Section 5.3 Biodiversity and Geological Conservation states that: “Where the

development is subject to EIA the applicant should ensure that the ES


[Environmental Statement] clearly sets out any effects on internationally, nationally

and locally designated sites of ecological or geological conservation importance, on

protected species and on habitats and other species identified as being of principal

importance for the conservation of biodiversity… The applicant should show how

the project has taken advantage of opportunities to conserve and enhance

biodiversity and geological conservation interests.”

11.2.12 The NPS document goes on to reiterate the Government’s biodiversity strategy

with its aim to ensure:

• “a halting, and if possible, a reversal, of declines in priority habitats and

species, with wild species and habitats as part of healthy, functioning

ecosystems; and

• the general acceptance of biodiversity’s essential role in enhancing the quality

of life, with its conservation becoming a natural consideration in all relevant

public, private and nongovernmental decisions and policies.”

11.2.13 The policy continues to say: “…development should aim to avoid significant harm

to biodiversity and geological conservation interests, including through mitigation

and consideration of reasonable alternatives… where significant harm cannot be

avoided, then appropriate compensation measures should be sought.”

11.2.14 Section 5.3.15 of the NPS EN-1 also refers to biodiversity within developments

stating: “Development proposals provide many opportunities for building-in

beneficial biodiversity or geological features as part of good design.”

11.2.15 With regards to Mitigation, section 5.3.18 states: “The applicant should include

appropriate mitigation measures as an integral part of the proposed development.

In particular, the applicant should demonstrate that:

• during construction, they will seek to ensure that activities will be confined to

the minimum areas required for the works;

• during construction and operation best practice will be followed to ensure that

risk of disturbance or damage to species or habitats is minimised, including as

a consequence of transport access arrangements;

• habitats will, where practicable, be restored after construction works have

finished; and


• opportunities will be taken to enhance existing habitats and, where practicable,

to create new habitats of value within the site landscaping proposals.”

EN-3, Overarching National Policy Statement for Renewable Energy Infrastructure

11.2.16 Paragraph 2.4.2 of NPS EN-3 describes the criteria for good design for energy

infrastructure. It states that: “Proposals for renewable energy infrastructure should

demonstrate good design in respect of landscape and visual amenity, and in the

design of the project to mitigate impacts such as noise and effects on ecology.”

National Planning Policy Framework

11.2.17 The National Planning Policy Framework (NPPF) for England sets out a number of

policies for conserving and enhancing the natural environment in Section 15

(paragraphs 170-183). Of particular relevance in the present context are the

following policies:

• 170: includes reference to the need to minimise risks to biodiversity and

promote net gains for biodiversity where possible, including establishing

coherent ecological networks (170 (d));

• 171: site protection should be commensurate with their status, and take a

strategic approach to maintaining and enhancing habitat networks;

• 175: addresses the conservation and enhancement of biodiversity in planning

applications;

• 177: the presumption in favour of sustainable development does not apply

when an Appropriate Assessment under the Habitats Regulations has

determined there will be an adverse effect on the integrity of a habitats site; and

• 180: includes policies to consider effects of pollution, including light pollution,

on the natural environment.

11.2.18 At the time of writing, the Environment Bill is currently passing through Parliament.

Amongst its most relevant provisions includes a strengthening of the duties under

Section 40 of the Natural Environment and Rural Communities Act 2006 to require

public authorities to enhance as well as conserve biodiversity. It will also introduce

a mandatory requirement for biodiversity net gain into the planning system1.

1 This currently only applies to planning applications determined under the Town and Country Planning Act 1990 and not DCO applications determined under the Planning Act 2008. However, it is clearly the direction of travel the Government are keen to promote for all development projects.


11.3 Consultation

11.3.1 The proposed scope of this assessment was set out in the Scoping Report

submitted to the PINS in November 2019 (see Appendix 2.1). Scoping Opinion

was received from PINS in December 2019 as adopted by the SoS which

contained responses from Natural England (NE) and KCC.

11.3.2 Table 11-1 sets out a record of the scoping responses and consultations that have

been undertaken with PINS, officers at KCC and NE and explains how they have

been taken into account in the PEIR.

Table 11-1: Scoping Response – Ecological matters

Scoping Opinion issue Response

Planning Inspectorate comments (with ID from Table 4.4 of Aspect Based Scoping Tables)

ID 4.4.1: Scoping Request sought to scope out surveys for Water Vole, GCN and white-clawed crayfish. The Inspectorate considers that the ES should include an assessment of these matters where a likely significant effect will occur. The Applicant should make effort to agree the approach to the assessment with the relevant consultation bodies. Any agreements reached with the consultation bodies in relation to the assessment of these matters should be presented and evidenced in the ES

Water vole presence is assessed in protected species walkover survey (Appendix 11-2); GCN by eDNA sampling and a Habitat Suitability Assessment (Appendix 11-4). Potential effects on white-clawed crayfish have been considered following receipt of biological records and with reference to potential effects on water environment (Appendix 11-1; this Chapter). KCC were satisfied with the scope of surveys proposed (see below) and further consultations held with NE under their DAS have not raised any further issues with ecological scope

ID 4.4.2: In the absence of sufficient information to the contrary PINS state that effects of lighting on ecological receptors should be appropriately assessed

Presence of light-sensitive ecological receptors assessed through bat survey results and consideration of surrounding habitats. PEIR cross-referenced with Lighting Assessment (Appendix 5-2)

ID 4.4.3: PINS do not agree that the construction phase effects from increased emissions and deposition to ecological receptors can be scoped out.

The methodology for assessing construction phase effects on sensitive ecological receptors is described in Appendix 13-2 Based on the fact that no sensitive ecological receptors have been identified within 50m of the Proposed Extension (see Table 11.3 below) construction phase effects can be scoped out from detailed ecological assessment.

ID 4.4.4: In addition to local, national and international nature conservation designations, assessment should consider SINCs as well as local BAP.

The assessment considers locally designated sites (see Appendix 11-1) and BAP priority habitats and species (see Appendix 11-2).



ID 4.4.5: Details of further compensatory habitat needs to be provided to offset loss

The assessment has used the beta version of Biodiversity Metric 2.0 to quantify habitat loss, in addition to a qualitative assessment with reference to priority habitats and other features. The landscape scheme, coupled with avoidance and restoration of some higher value component features, has been designed to achieve partial compensation with a non-significant residual effect.

ID 4.4.6: All ecological survey work relied upon to inform the ecological assessment and the results, should be included either within the ES or appended to the ES. To aid the readers understanding, figures that depict survey locations, habitat coverage, and the locations of protected species, potential habitats should also be included within or appended to the ES

Supporting ecological survey reports are provided in Appendices 11-3 to 11-6, including appropriate figures.

ID 4.4.7: The ES should include details of all GCN surveys relied upon, either as part of the ecology chapter or as appendices. The Applicant should make effort to agree with relevant consultation bodies (notably Natural England) whether further GCN surveys are required

A Reptile and Amphibian survey report is provided (Appendix 11-4) which includes details of the GCN habitat suitability assessment, eDNA sampling, and the results of refugia surveys.

ID 4.4.8: Cumulative assessment. The Inspectorate recommends that guidance used for this assessment should be clearly set out and how it has been applied in the assessment of cumulative ecological effects and air quality effects on ecological receptors

Cumulative air quality effects are considered in Chapter 13 and Appendix 13-3. The HRA Report (Appendix 11-8) takes into account cumulative air quality effects on North Downs Woodlands SAC, following further consultation and advice from NE and KCC.

ID 4.4.9: List of baseline monitoring surveys omits reference to botanical, full ornithological, terrestrial, and marine invertebrates, and terrestrial and marine mammal surveys. Applicant should consider the need for these surveys.

Botanical, ornithological, terrestrial, and aquatic invertebrate surveys have been undertaken; protected species risk assessment incorporates a mammal survey (see Appendices 11-2 to 11-6). Marine fauna scoped out due to avoidance of risk to Medway MCZ through measures set out Chapter 12 (Water Quality and Drainage).

ID 4.4.10: The Scoping Report includes an intention for the ES to present ecological enhancement measures, if required, as part of the Proposed Development. The ES should clearly distinguish between the measures that are presented as mitigation in response to identified significant effects, and enhancement measures which the Applicant identifies as being in addition to the necessary mitigation measures. Mitigation measures, including any plans, should be sufficiently developed and secured through the DCO or other legal mechanism

The PEIR presents a series of ecological mitigation measures which are integrated into the construction methods and landscape design of the Proposed Extension. In addition, enhancement measures are proposed with respect to achieving BM 2.0 offsetting targets with a mixture of on-site and appropriately secured off-site mitigation (see Appendices 11-9 – 11-13)

ID 4.4.11: ES should state effects during construction and operation on the River Medway

The PEIR cross references the ecological impact assessment to the Water Quality and Drainage assessment (Chapter 12) in order to assess effects on River Medway / Medway Estuary.



Kent County Council comments (ecology)

KCC has reviewed the ecological information submitted within the Scoping Report and is satisfied with the range of surveys which are been carried out. All of this material must be included within the Environmental Statement (ES) when submitted

The PEIR includes reports of all ecological surveys undertaken as Technical Appendices to this document

The scoping report states that the following surveys/assessments are being undertaken: • Extended Phase 1 Habitat / Phase 2 Habitat Survey; • Environmental DNA (eDNA) sampling for Great Crested Newt (GCN) presence; • Breeding bird survey; • Freshwater invertebrate sampling;

• Butterfly/dragonfly transect; • Bat activity surveys/automated monitoring; • Reptile surveys; and • Protected species risk assessment.

All surveys proposed in the Scoping Report have been undertaken and are included as Technical Appendices.

The County Council is satisfied with the range of ecological surveys that are being carried out and advises that the results, as well as necessary mitigation strategies, are submitted with any planning application

Mitigation / compensation strategies are included in the PEIR where necessary.

It is advised that any potential impact of the proposed extension on features of nature conservation interest, as well as opportunities for habitat creation/ enhancement, will need to be included within the ES. Given that an area of botanically interesting grassland will be lost for the proposed development, details of the proposed compensation site (that will be surveyed prior to the production of an ES) must be submitted with the Development Consent Order (DCO) application.

Areas of higher quality grassland within the Site have been identified and mapped. Compensatory works including on-site soil transfer to the new landscape, will be included with the DCO application. Details of off-site compensatory habitat creation are included in the PEIR.

There are no designated sites for ecology in close enough proximity to incur direct impacts from the construction phase. However, there is the potential for effects to occur within the North Downs Woodlands Special Area of Conservation (SAC) to the north, should there be a change in air quality once the development is operational

The sensitivity of North Downs Woodlands SAC has been assessed by reference to Air Pollution Information Service (APIS) guidance, together with a site visit. Impacts have been modelled during the Stack Height Assessment process, and mitigation measures incorporated in the Project design to avoid exceedance of screening thresholds

The Scoping Report states that an air quality survey will be undertaken to assess the potential impact on the SAC. This information must be included within the ES, and the Environment Agency and Natural England should be consulted.

The PEIR includes an ecological interpretation of the Emissions Modelling Assessment, which addresses potential impacts to the SAC.



Natural England Comments

Natural England advises that the potential impact of the proposed extension upon features of nature conservation interest and opportunities for habitat creation/ enhancement should be included within this assessment in accordance with appropriate guidance on such matters. Guidelines for Ecological Impact Assessment (EcIA) have been developed by the Chartered Institute of Ecology and Environmental Management (CIEEM) and are available on their website

The assessment has been undertaken with reference to and in accordance with CIEEM guidance.

The ES should thoroughly assess the potential for the proposal to affect designated sites. European sites (e.g. designated Special Areas of Conservation and Special Protection Areas) fall within the scope of the Conservation of Habitats and Species Regulations 2017 (as amended). In addition, paragraph 176 of the National Planning Policy Framework requires that potential Special Protection Areas, possible Special Areas of Conservation, listed or proposed Ramsar sites, and any site identified as being necessary to compensate for adverse impacts on classified, potential, or possible SPAs, SACs and Ramsar sites be treated in the same way as classified sites

The assessment includes consideration of effects on all European sites within 10km of the Project

Under Regulation 63 of the Conservation of Habitats and Species Regulations 2017 (as amended) an appropriate assessment needs to be undertaken in respect of any plan or project which is (a) likely to have a significant effect on a European site (either alone or in combination with other plans or projects) and (b) not directly connected with or necessary to the management of the site

An HRA Report has been prepared to assess the effects of the Project on North Downs Woodlands SAC, including consideration of in-combination effects. Natural England have provided advice through their Discretionary Advice Service (DAS) on the assessment of effects on the SAC

The EIA will need to consider any impacts upon local wildlife and geological sites.

Details of local sites have been obtained from KMBRC and any impacts on them are considered have been assessed

The ES should assess the impact of all phases of the proposal on protected species (including, for example, great crested newts, reptiles, birds, water voles, badgers and bats). The area likely to be affected by the proposal should be thoroughly surveyed by competent ecologists at appropriate times of year for relevant species and the survey results, impact assessments and appropriate accompanying mitigation strategies included as part of the ES

A programme of protected species surveys has been undertaken at optimum times of year; assessment of impacts undertaken and mitigation strategies developed where appropriate

The ES should thoroughly assess the impact of the proposals on habitats and/or species listed as ‘Habitats and Species of Principal Importance’ within the England Biodiversity List

The assessment has included consideration of effects on habitats or species of principle importance for biodiversity conservation.


Additional consultation

11.3.3 Further consultation has been carried out with NE and KCC to discuss the scope

and results of ecological and air quality assessments.

11.3.4 Two videoconferencing meetings have been held with NE, including a member of

their local team and an air quality specialist. The primary purpose of these

consultations was to present the results of the air quality assessment as they

related to North Downs Woodlands Special Area of Conservation (SAC), take

advice on cumulative assessment, and confirm the acceptability of the approach

taken. The matters agreed with NE have been taken into account in the preparation

of this PEIR chapter and the associated appendices. It is the intention of the

Applicant to secure a formal Statement of Common Ground on these matters in

due course.

11.3.5 A videoconference meeting was held with KCC ecological and planning staff to

discuss the approach to biodiversity offsetting, including the off-site enhancement

proposals. The results of the initial Biodiversity Metric 2.0 spreadsheet calculations

were shared, and feedback was provided to them on the results of ecological

survey works.

11.4 Parameters Used for Assessment

11.4.1 The overall approach to the use of the Rochdale Envelope and the Parameters that

have been assumed for the assessment of likely significant environmental effects

arising from the Proposed Extension is set out in Chapter 5.0 of this PEIR. Those

parameters have been used, where relevant, to inform the assessments in each

topic specific chapter of this PEIR.

11.4.2 In order to provide a robust assessment, each topic specific chapter has been

prepared on a reasonable worst-case scenario for that given topic. This being the

worst-case scenario that could reasonably be expected to occur within each of the

parameters set. The reasonable worst-case scenario for each topic differs

depending upon the particular assessments being undertaken. However, all

assessments have been undertaken within the broadest reasonable parameters, to

ensure the assessment is precautionary in its approach.


11.4.3 With respect to the ecological assessment, the reasonable worst-case scenario for

the Proposed Extension has been based upon the following assumptions:

• The permanent loss of habitat within the areas of built development /

impermeable areas on the Site - based upon the maximum extent of such

development on the works schedule. This excludes the temporary laydown area

in the construction phase which is to be included in the final landscape scheme.

• The temporary loss of all existing habitat within the areas identified on the

earthworks plan (see figures 5.8a – 5.8i).

• The retention of existing habitat on the areas unaffected by the proposed

earthworks.

• The ecological effects arising from other technical issues (for example, changes

in air quality, noise or hydrology) have also been taken into consideration and

the effects have been assessed based on outcome of the modelling undertaken

within each of the assessments. The assessments have also been prepared on

the basis of reasonable worst-case parameters.

11.4.4 The preferred route of the electrical connection from the Proposed Extension is

along the A20 utilising the existing carriageway and footpath. However, if that route

is not deemed feasible, use of the grid route for the Existing Station has also been

considered. The latter route does have greater potential to impact upon natural and

semi-natural habitat which would be disturbed during its construction. Whilst only

one route would be selected, the reasonable worst-case assumes that it could be

either and both options have been assessed.

11.5 Assessment Methodology

Assessment Methodology

11.5.1 Impact assessment methodology follows current Chartered Institute of Ecology and

Environmental Management guidelines (CIEEM, 20162, CIEEM, 20183). This is

based on:

• the identification of valued ecological resources;

• the characterisation of potential impacts as a consequence of the development;

2 CIEEM (2016). Guidelines for Ecological Impact Assessment in the UK and Ireland. Terrestrial, Freshwater and Coastal. Second Edition, January 2016 3 CIEEM (2018). Guidelines for Ecological Impact Assessment in the UK and Ireland. Terrestrial, Freshwater, Coastal and Marine. Version 1.1., September 2019.


• an assessment of the likelihood of occurrence, duration, extent, magnitude,

frequency and reversibility; and

• an assessment of impact significance.

11.5.2 In order to assess the effects of a development on flora and fauna, it is first

necessary to identify the nature and geographical extent of likely impacts and

identify the component ecological interest features of the receiving environment.

This process identifies important ecological features which should be subject to

further assessment. These are features which are sufficiently important and

potentially affected by the project; CIEEM guidelines state “it is not necessary to

carry out detailed assessment of features that are sufficiently widespread,

unthreatened and resilient to project impacts and will remain viable and

sustainable.”

11.5.3 The identification of ecological effects also takes incorporated mitigation measures

into account. These comprise already committed measures, which the decision

maker can be confident would be included as part of the Proposed Extension; they

are described at the start of section 11.7 below.

11.5.4 The valuation of habitats and quantification of gains and losses as a consequence

of the Proposed Extension has been undertaken in accordance with the guidance

set out in Biodiversity Metric 2.04.

Scope of Assessment

Study Area

11.5.5 The study area used for identification of sensitive ecological receptors, survey and

assessment of effects has been undertaken in accordance with CIEEM guidance5.

This states that the scope and area that should be considered for study should be

based on the professional judgment of the ecologist, taking into account factors

such as the characteristics of the site subject to appraisal, its surroundings and the

nature of the changes proposed. For the purposes of assessing air quality impacts,

4 Crosher, I.A., Gold, S.B., Heaver, M.D., Heydon, M.A., Moore, L.D., Panks, S.A., Scott, S.C., Stone, D.A. & White, N.A. (2019). The Biodiversity Metric 2.0: auditing and accounting for biodiversity value. User guide (Beta Version, July 2019). Natural England Joint Publication JP029 5 CIEEM (2013). Guidelines for Preliminary Ecological Appraisal. Technical Guidance Series.


screening distances determined by Environment Agency guidance and employed in

the Air Quality assessment (Chapter 13.0) have been used.

11.5.6 For the purposes of collating protected and priority species data, a 2km distance

from the Site boundary provides an appropriate study area, providing contextual

data on species which may occur on Site. This is also appropriate for UK-

designated statutory conservation sites, and non-statutory locally designated sites.

11.5.7 For air quality assessment purposes, a 2km radius from the emission source is

appropriate for assessing effects on nationally and locally important conservation

sites and ancient woodlands. For European (Natura 2000) sites, a 10km radius

from the emission source is used. With respect to construction phase dust

emissions, all sites within 50m of the Site boundary are considered.

11.5.8 With respect to ecological surveys, the study area is defined by the Site boundary

shown in Appendix 11-2, Figure A11.2.1. As the Site is bounded by major roads

and built development, it was not appropriate to include a wider buffer zone for

most surveys. The exception is bird surveys, where efforts were made to record

birds utilising land or airspace within 200m of the Site boundary.

Ecological Scoping Process

11.5.9 An initial desktop study was carried out to assess the ecological sensitivity of the

Site and its context, including the presence of statutory designated conservation

sites which could be regarded as sensitive receptors for air quality assessment.

11.5.10 A data search was commissioned from KMBRC for non-statutory designated sites,

protected and priority species records within a 3km radius of a point within the area

of the Proposed Extension. This captured all records within 2km of the Site

boundary.

11.5.11 In order to undertake ecological survey works during the optimum season, bird

survey work and great crested newt (GCN) eDNA sampling / habitat suitability

assessment commenced in spring 2019, in advance of the submission of the formal

Scoping Report.


11.5.12 Based on the results of the initial site surveys and data searches, a programme of

ecological survey work was initiated and undertaken through the 2019 survey

season.

11.5.13 The following ecological surveys were undertaken; full details of methodology,

timings and personnel are provided in the relevant Technical Appendices:

• Extended Phase 1 Habitat Survey / UK Habitat Classification Survey;

• Great crested newt eDNA sampling and habitat suitability assessment;

• Aquatic and terrestrial invertebrate survey;

• Reptile and Amphibian survey;

• Breeding bird survey;

• Protected species walkover survey; and

• Bat activity surveys and assessment of roost potential.

11.5.14 All surveys were undertaken by appropriately qualified ecologists, during the

optimum field season in 2019.

11.5.15 In addition to ecological site surveys, North Downs Woodlands SAC was visited to

obtain further information on its potential vulnerability to air quality effects. Two

closed landfill sites were also visited in order to assess their potential to provide off-

site mitigation as part of the biodiversity offsetting process.

11.5.16 Information obtained from the data searches, site visit and initial field survey results

were summarised in the Ecology section of the Scoping Report submitted to PINS.

The outcome of the scoping exercise and the scoping responses received from

PINS, KCC and other statutory consultees, and how they have been taken into

account in this PEIR, is set out Section 11.3 above.

Assessment of Significance / Assessment Criteria

11.5.17 In the CIEEM (2018) guidelines a significant effect in ecological terms is defined as

an effect that: “either supports or undermines biodiversity conservation objectives

for important ecological features or for biodiversity in general.” In EIA terms, this is

an effect that is sufficiently important to require assessment and reporting so that

the decision maker is adequately informed of the environmental consequences of

permitting a project.


11.5.18 In common with the approach taken elsewhere in this PEIR, CIEEM guidance does

not define particular levels of significance. However, a geographic scale at which

the effect is significant is applied where appropriate, in order to determine a

proportionate response in developing mitigation measures and help inform the

decision-making response to any residual effects.

11.5.19 Any significant ecological effects are subject, wherever feasible, to additional

mitigation measures, with the aim of avoidance, reduction or compensation. The

significance of residual effects is then re-assessed.

Assessment of air quality effects

11.5.20 The assessment of air quality effects on natural habitats has been undertaken as

an iterative process in collaboration with the Stack Height and Emissions Modelling

Assessments reported in Chapter 13.0 of this PEIR. This was undertaken in

accordance with IAQM (2019) guidance with regard to the respective roles of air

quality specialists and ecologists.

11.5.21 In accordance with IAQM guidance, air quality impacts on sensitive ecological

receptors in excess of screening thresholds would be subject to further ecological

assessment, normally presented in a Technical Appendix. In the case of the

Proposed Extension, incorporated mitigation measures have reduced the predicted

effects below screening thresholds, obviating the need for detailed ecological

interpretation. However, in accordance with case law in respect of incorporated

mitigation, a Habitats Regulations Assessment (HRA) Report (Appendix 11-8) has

been compiled, which addresses the issue of air quality effects on European

designated sites. Appendix 11-7 also incorporates the results of a survey of North

Downs Woodlands SAC, undertaken to improve the authors understanding of the

site’s condition and sensitivity to potential air quality effects.

Limitations

11.5.22 The surveys described in Appendices 11-1 – 11-7 were undertaken at appropriate

seasons for the relevant taxa and did not report any constraints which may have

affected the validity of the results. As with any ecological surveys, the use of a site

by fauna and the development of vegetation may change over time, sometimes

over short timescales.


11.6 Baseline

Baseline Ecological Data

11.6.1 The following section summarises baseline ecological data relating to the Site and

its surroundings, which are set out in more detail in the Technical Appendices. See

Appendix 11-1 (PEA) for more details of the data search, including statutory and

locally designated sites, and protected and priority species recorded within a 2km

radius of the Proposed Extension. Appendix 11-2 provides further details of

habitats present on Site, and a valuation of baseline habitats in accordance with

Biodiversity Metric 2.0 and Appendices 11-3 – 11-7 provide more details of faunal

survey results.

Site Context

Statutory Designated Sites

11.6.2 The location of Natura 2000 (European designated sites) within a 10km radius is

tabulated below. These include three Special Areas of Conservation (SAC). There

are no Special Protection Areas (SPA) or Ramsar Sites within the 10km search

radius.

Table 11.2: Natura 2000 Sites within 10km of Proposed Extension

Site Status Distance (to nearest point)

Qualifying Features

North Downs Woodlands

SAC 2.7km NE Beech woodland

Yew woodland

Calcareous grassland

Peter’s Pit SAC 5km NW Great crested newt

Queendown Warren SAC 9.6km NE Calcareous grassland

11.6.3 Further details of qualifying features are given in Appendix 11-1. Appendix 11-7

provides more details on site condition and conservation objectives with respect to

the North Downs Woodland SAC.


UK Statutory Designated Sites

11.6.4 There are two Sites of Special Scientific Interest (SSSIs), one Local Nature

Reserve (LNR) and one Marine Conservation Zone (MCZ) within the 2km study

area.

Table 11.3: UK Statutory Designated sites within 2km

Site and Designation Location (nearest) Features of Interest

Allington Quarry SSSI 0.37km SE Geological

Aylesford Old Pit SSSI 1.8km NW Geological

Ditton Quarry LNR 2.1km SW Calcareous grassland and scrub

Medway MCZ 0.30km NE Marine / estuarine habitats and geomorphological

features

Tentacled lagoon-worm

Smelt

11.6.5 Sites designated for geological interest only are not considered further in terms of

the ecological assessment. Further details of Ditton Quarry LNR and Medway MCZ

are given in Appendix 11-1.

Non-statutory Designated Sites and Ancient Woodlands

11.6.6 Information on non-statutory designated sites within 2km of the Proposed

Extension has been obtained from KMBRC; ancient woodland sites were identified

using Natural England’s Ancient Woodland Inventory v3.7 digital boundary data.

The following Local Wildlife Sites (LWS) and ancient semi-natural woodlands occur

within the search radius.

Table 11.4: Local Wildlife Sites and Ancient Woodlands within 2km

Site and Designation Location (nearest) Features of Interest

Lock Wood 0.7km NE Ancient woodland

Sandling Wood 1.8km E Ancient woodland

Dog Kennel Wood 1.4km SW Ancient woodland

Broke Wood 1.8km SW Ancient woodland

Fullingpits Wood 1.9km SW Ancient woodland

Aylesford Old Pit LWS 1.5km NW Calcareous grassland

Cuckoo Wood LWS 1.9km E Beech woodland

Blue Bell Hill Banks and Verges LWS 1.9km NE Calcareous grassland


11.6.7 Further details of location and ecological interest features are given in Appendix

11-1; sensitivity to air quality effects is considered further in Appendix 11.7.

Protected Species Records

11.6.8 Records of European protected species obtained from KMBRC included great

crested newt (Triturus cristatus; GCN). The nearest records are over 1.1km from

the Site boundary at Aylesford to the NW, and M20 Junction 6 to the NE. They are

both separated from the Site by the River Medway and the major road network.

11.6.9 There was one otter (Lutra lutra) record from Maidstone, dating from 1987.

11.6.10 Bat records from the 2km search area included serotine (Eptesicus serotinus),

noctule (Nyctalus noctula), Leisler’s bat (Nyctalus leisleri), Daubenton’s bat (Myotis

daubentoni), Natterer’s bat (Myotis nattererii), whiskered bat (Myotis mystacinus),

common pipistrelle (Pipistrellus pipistrellus), soprano pipistrelle (Pipistrellus

pygmaeus) and brown long-eared bat (Plecotus auritus). The nearest known roost

location is approximately 220m south-west of the nearest Site boundary.

11.6.11 There were a number of records of UK protected species, protected under

Schedule 5 of the Wildlife and Countryside Act 1981. These included the three

commoner reptile species: grass snake (Natrix natrix), adder (Vipera berus) and

slow-worm (Anguis fragilis). One of the adder records was described as being from

Allington; this is only localised to a 1km grid reference, and dates from 1989.

11.6.12 Records of water vole (Arvicola amphibia) are mostly historic (20th century),

reflecting the population decline and range contraction of this species. More recent

records up to 2016 are located in the Aylesford area, north of the Site and

separated from it by the M20 and River Medway.

11.6.13 Records obtained from biological records centres cannot be considered as

comprehensive and were not relied upon to determine the scope of the survey

programme, without careful consideration of the likely risk of occurrence on or near

the Site.


Priority Species Records

11.6.14 The KMBRC data returned a large number of priority species records in the 2km

study area, defined as those listed on Section 41 of the Natural Environment and

Rural Communities Act 2006. None of these were localised to the Site or

immediate surrounds. Further details are given in Appendix 11-1.

Other Species of Conservation Interest

11.6.15 A Nationally Scarce water beetle, Helophorus alternans, has a 2009 record from a

wetland in the western part of the Site.

Habitats and Vegetation

Local Ecological Context

11.6.16 The Site is located in the Medway Valley, around 300m from the River Medway at

its nearest (north-eastern) boundary.

11.6.17 The Site is relatively isolated from the surrounding landscape and other wildlife

habitats by industrial development, major road and rail infrastructure. It is bounded

to the east by the 20/20 Business Park; to the north by the M20; to the south by the

industrial estate access road and the Maidstone – London rail line; and to the

south-west and west by the A20 dual carriageway and A20 – M20 link road.

Habitats within Site

11.6.18 The Extended Phase 1 / NVC / UKHC habitat survey is described in detail in

Appendix 11-2 and illustrated in Figures A11.2.1 and A11.2.2 of that report. The

following provides a summary of the habitats and component species in the survey

area.

11.6.19 The eastern part of the survey area consists of the Existing Station and associated

infrastructure, including amenity grassland and an attenuation pond to the north

east, and flat area of bare aggregate, ephemeral – short perennial vegetation and

grassland with scattered scrub to the west. These features are enclosed within tall

bunds to the north, east and west, formed when the Existing Station was


constructed. The bunds support a mix of scrub, young plantation woodland,

grassland, tall ruderal and ephemeral – short perennial habitats. Another bund to

the south is shorter in height, and densely wooded with immature plantation

woodland.

11.6.20 The western part of the survey area consists of a shallow bowl landform restored

from a former chalk quarry after landfilling, which retains a section of sparsely

vegetated exposed rock on the former quarry floor, adjoining a pond which acts as

a soakaway for drainage from the surrounding slopes and roof water from the

Existing Station. The quarry bowl mostly supports relatively species-poor neutral

grassland with scattered scrub, although there are areas of more diverse

grassland, particularly in the northern part of the bowl, including areas with locally

frequent pyramidal and bee orchids (Anacamptis pyramidalis, Ophrys apifera). The

upper parts of the bowl support patches of dense scrub, and there is an area of tall

ruderal vegetation on the northern slope.

Fauna

Freshwater Invertebrates

11.6.21 The existing pond was sampled using standard, timed methods, and samples

preserved for laboratory identification by a freshwater ecologist. The nationally

notable water beetle Helophorus alternans was not found in the sample. The

sample contained large numbers of bivalves, Diptera (true fly) larvae (including the

soldier-fly Stratiomys potamida) and water hog-louse (Asellus aquaticus). There

were also good numbers of Odonata (dragonfly and damselfly) larvae.

11.6.22 Diversity of the taxa identifiable to species level was low, with only 3 species of

Odonata, three Hemiptera (water bugs) and one Stratiomyidae (soldier-fly) species

recorded. No Priority Species, Nationally Scarce or notable species were recorded.

Terrestrial Invertebrates

11.6.23 18 species of butterfly were recorded; all were common and widespread species,

although three have experienced population declines and are listed as Section 41

Priority Species: wall (Lasimiomatta megera), small heath (Coenonympha


pamphilus) and dingy skipper (Erynnis tages). One diurnal moth species recorded

in the surveys is also listed on Section 41: cinnabar moth (Tyria jacobaeae).

11.6.24 The invertebrate fauna is indicative of relatively new habitats. Most Lepidoptera

and Odonata were found in grassland habitats, with very few within the young

plantations or bunds that had been planted in the west of the Site or around the

bunds to the south and east. There were good numbers of Hymenoptera (bees and

wasps) within grassland habitats, but low species diversity.

Amphibians

11.6.25 Negative eDNA results have confirmed that neither the existing pond or the existing

surface water attenuation lagoon on the Site support great crested newts (GCN); in

addition, no amphibians were recorded under refugia in the course of reptile

surveys.

11.6.26 The M20 motorway and River Medway presents significant barriers between the

Site and the nearest known GCN breeding ponds over 1km to the north-east and

north-west.

Reptiles

11.6.27 No reptile species were found on the Site.

Breeding Birds

11.6.28 A total of 23 bird species were seen in the surveys, including 21 which were

thought to be at least possibly breeding on the Site. These were all common and

widespread species; species with the largest number of territories were blackbird

(Turdus merula: 20 territories), wren (Troglodytes troglodytes: 16) and blue tit

(Cyanistes caeruleus: 16).

11.6.29 Two Section 41 Priority Species were recorded; dunnock (Prunella modularis: 8

territories) and linnet (Carduelis cannabina: 1).

11.6.30 One protected species listed in Schedule 1 of the Wildlife and Countryside Act

1981 was recorded. An adult and juvenile peregrine falcon (Falco peregrinus) were


present on the emission stack of the Existing Station. Although tall industrial

structures provide suitable nesting sites for this species, they were not recorded on

Site until after the breeding season and were not believed to have bred there.

Bats

11.6.31 Seven species of bats were recorded in the transect and automated monitoring

surveys: common pipistrelle, soprano pipistrelle, Myotis sp., noctule, Leisler’s bat,

serotine and brown long-eared bat. With the proviso that the Myotis recordings

could not be identified to species, these are all species recorded in the 2km data

search.

11.6.32 Transect surveys revealed relatively low levels of bat activity across the Site with

only common pipistrelle, soprano pipistrelle and noctules being detected in any

numbers. The Anabat detectors which were effectively detecting in two parts of the

Site for 46 days (92 days of data in total) detected a wider range of species, but

numbers of passes were still relatively lower than would have been expected for

the habitat.

11.6.33 Transect surveys did not detect any ‘hotspot’ areas of higher activity. Before the

survey it was expected that the pond in the western part of the Site might be a

focus of bat foraging activity, but activity levels were not noticeably elevated above

surrounding habitats. This may be due to the fringing willow scrub and emergent

vegetation, with limited flight paths over open water habitat.

11.6.34 There were very few features on Site which could provide potential roosting

opportunities for bats, with most trees in the surrounding plantations too young to

develop roost features. A taller hybrid black poplar tree near the site perimeter was

subject to a more detailed ground-level inspection and emergence survey, but no

evidence of use by bats was evident.

Other Fauna

11.6.35 A protected species walkover survey did not detect any signs of use by badger

(Meles meles); there were no signs of water vole or otter activity associated with

wetland / settlement pond habitats on Site.


Invasive Species

11.6.36 No non-native invasive species listed on Schedule 9 of the Wildlife and Countryside

Act 1981 were recorded on or near the Site.

Future Baseline

11.6.37 In the absence of the Proposed Extension, the buildings and activities associated

with the Existing Station would continue to operate in the eastern area of the Site.

Vegetation on the surrounding bunds would continue to mature. In the longer term

this would potentially provide more deadwood and crevice habitats suitable for bats

and other fauna, although this is dependent on future management.

11.6.38 The western part of the site, within the landfilled and restored former quarry, is

managed as a Nature Conservation Area under a Section 106 agreement. This is

due to be handed over to a management company, who are obliged to manage the

area in accordance with the Kent Biodiversity Action Plan, in order to achieve

ecological enhancement of the site.

11.6.39 Although the ecological assessment has concluded that it does not currently meet

Kent Local Wildlife Site selection criteria6, as habitats mature it is likely to acquire a

higher biodiversity interest.

11.6.40 However, increasing maturity of component habitats is not unequivocally positive;

species diversity may decline in grassland habitats if taller, more competitive

species such as false oat-grass (Arrhenatherum elatius) continue to increase in

abundance. Intermediate stages of woodland succession, where the canopy is at

scrub height, can support a higher breeding bird density than dense, even-aged

plantation woodland.

11.6.41 The future ecological baseline is clearly influenced by management, as

interventions such as mowing or grazing can serve to maintain grassland species

richness. However, the relative isolation of the Site from habitats in the surrounding

landscape will act as a brake on colonisation by less mobile flora and fauna and

may limit future species diversity.

6 Kent Wildlife Trust (2015). Local Wildlife Sites in Kent. Criteria for Selection and Delineation. Version 1.5, October 2015.


mportant Ecological Features

Designated Sites

11.6.42 The European sites listed in Table 11.2 can be considered as ecological features

on an international scale of importance. Although none are within 2km of the Site,

they are particularly relevant with respect to the consideration of air quality impacts.

11.6.43 Ditton Quarry Local Nature Reserve (Table 11.3) can be considered as an

ecological feature of County-level importance.

11.6.44 The Local Wildlife Sites listed in Table 11.4 can be considered as ecological

features of County-level importance, designated in the context of quality standards

set across Kent by the Wildlife Trust and Kent Nature Partnership. All sites within

2km of the Site are relevant for consideration of air quality impacts; none are close

enough to be exposed to near-site effects such as noise, dust or human

disturbance.

11.6.45 Ancient woodland sites listed in Table 11.4 can be regarded as being of local to

County-level importance. In the context of EIA, because ancient woodland sites

cannot be restored or recreated in a realistic timescale, they are regarded as

‘critical natural capital’. The loss of ancient woodland cannot be effectively

mitigated by creation of new habitats.

Protected Species

11.6.46 In order to assess the level of value of protected species as important ecological

features, it is necessary to consider the following:

• the extent to which the Site contributes to the maintenance of their conservation

status in the wider area; and

• their level of legal protection, in order to address whether and how the

Proposed Extension could proceed in accordance with current legislation, and

assess whether any operations may require a Natural England disturbance

licence.

11.6.47 A total of seven European protected species have been recorded within the Site,

and one bird species with special protection under UK law.


11.6.48 All bat species are protected through listing under Annex IVa of the EU Habitats

Directive, as implemented in England and Wales through Regulation 42 of the

Habitats Regulations 2017. Peregrine falcon has special protection through listing

in Schedule 1 of the Wildlife and Countryside Act 1981.

11.6.49 Although habitat quality is quite good for bats on the Site, foraging activity was

significantly lower than expected, most likely due to the proximity of major roads,

and the Site offers few opportunities for roosting. Bats can therefore be regarded

as being of no more than within-site importance as ecological interest features.

11.6.50 Peregrine falcon were only recorded after the end of the breeding season, with an

already-fledged juvenile and adult falcon recorded on the stack. Although the Site

was being used for resting and probably foraging, it cannot be regarded as being of

more than local importance for this species, as there was no evidence of

occupancy during the breeding season, and the Site represents only a small

proportion of likely home range.

11.6.51 All bird species are protected under the Wildlife and Countryside Act from

deliberate killing or injury, or destruction of nests, eggs or dependent young. The

Site’s avifauna cannot be regarded as being of more than within-site importance,

comprising moderate territory numbers of common and widespread species.

However, the legal protection afforded to birds means that mitigation measures will

be necessary to maintain legal compliance. The breeding bird assemblage is

therefore treated as an interest feature of local importance in the subsequent

impact assessment and mitigation proposals.

Priority Species

11.6.52 A number of Priority Species were recorded on the Site during the course of survey

work, including two breeding birds and four Lepidoptera species. Although subject

to significant past population declines, they remain common and widespread

species; there is no evidence of dependence on habitats within or adjoining the Site

and they cannot be regarded as important ecological features for the purposes of

the EIA.


Priority Habitats

11.6.53 Appendix 11-2, Section 4.1 considered whether the Site supported any priority

habitats. Based on the extended Phase 1 & NVC surveys, the potential occurrence

of the following habitats was discussed:

• Lowland Mixed Deciduous Woodland;

• Lowland Meadows;

• Ponds;

• Reedbeds; and

• Open Mosaic Habitats on Previously Developed Land.

11.6.54 The evaluation concluded that only Lowland Mixed Deciduous Woodland priority

habitat occurred on Site, with other habitats not meeting the quality standards of

the published habitat descriptions.

11.6.55 Lowland Mixed Deciduous Woodland priority habitat is confined to a narrow strip

adjoining the M20. Appendix 11-2 explores how this is a small remnant of what

was previously a larger area of woodland which was fragmented by construction of

the M20. As a priority habitat, it can be considered an ecological interest feature of

local importance.

11.6.56 In the wider vicinity of the Site, the River Medway is an example of Rivers and

Streams Priority Habitat; it also supports a number of species of conservation

interest and contributes to the maintenance of ecological networks. It does not

have any statutory conservation designations upstream of the lower estuary but

can be regarded as an ecological feature of County level importance.

Other Important Ecological Features

11.6.57 Although not qualifying as a priority habitat, the relatively more species-rich areas

of grassland which support pyramidal orchid and bee orchid can be considered as

important ecological features of local importance. The complex of habitats

associated with the wetland area in the western part of the Site, including emergent

vegetation, aquatic vegetation, scrub and adjoining ephemeral – short perennial

vegetation can also be considered as a feature of local importance.


Valuation of Baseline Habitats on Site

11.6.58 The value of baseline habitats has been calculated for the Site in accordance with

the BM 2.07. The basis for this calculation is set out in more detail in Appendix 11-

2. Current habitat baseline has been calculated at 239.15 biodiversity units. This

takes into account habitat condition, and encompasses the whole of the Site,

including vegetation around the Existing Station.

Summary of Important Ecological Features

11.6.59 Table 11.5 below summarises important ecological features which should be

considered in the assessment of ecological effects.

Table 11.5: Summary of Important Ecological Features

Feature Legal and policy status Level of importance

North Downs Woodlands SAC Articles 3 & 4, Habitats Directive; Habitats Regulations 2017; NPPF paras.

170-71 & 177.

International

Ditton Quarry LNR National Parks and Access to the Countryside Act 1949

County level

River Medway Water Framework Directive County level

Aylesford Old Pit LWS NPPF p. 171 County level

Cuckoo Wood LWS NPPF p. 171 County level

Blue Bell Hill Banks and Verges LWS

NPPF p. 171 County level

Lock Wood NPPF p. 171 Local

Sandling Wood NPPF p. 171 Local

Dog Kennel Wood NPPF p. 171 Local

Broke Wood NPPF p. 171 Local

Fullingpits Wood NPPF p. 171 Local

Lowland Mixed Deciduous Woodland

Section 41, Natural Environment & Rural Communities Act 2006

Local

Neutral grassland habitat (relatively species-rich areas with orchids)

NPPF p. 171 Local

Wetland habitats – pond, reedbed, willow scrub

NPPF p. 171 Local

7 Biodiversity Metric 2.0 – Calculation Tool Beta Test. December 2019 version


Feature Legal and policy status Level of importance

Peregrine Falcon Schedule 1; Section 1.1, Wildlife and Countryside Act 1981

Local

Breeding bird assemblage Section 1, Wildlife and Countryside Act 1981

Within-site but legal protection

The HWRC Scenario

11.6.60 A separate planning application for a HWRC at the north-eastern edge of the Site

was submitted in December 2019 (application reference KCC/TM/0284/2019) and

is awaiting determination at the time of writing. As such, and as discussed in

more detail in Chapter 6.0, it is necessary for the ecological assessment to also

consider a second scenario, where the HWRC is implemented.

11.6.61 The HWRC would comprise:

• A new household waste recycling facility (the HWRC);

• A New access from Laverstoke Road;

• Re-engineering of existing perimeter earth bund;

• Loss of existing tree cover; and

• New native woodland planting.

11.6.62 The HWRC is being proposed on the existing bund that is located immediately to

the east of the Existing Station, separating and screening it from the 20/20

Business Park. In order to construct the HWRC, it would be necessary to carry out

ground re-modelling over a large section of the eastern bund (around 2.3ha in

total). This process would result in the loss of all the existing vegetation within the

affected area, with only a small amount being the subject of replacement through

a proposed landscape scheme (Figure 9.6b).

11.6.63 The earth excavated in the construction of the HWRC facility would be placed on

the bund located to the South of the Existing Station (see Figure 5.4e). This

currently supports a mosaic of grassland, scrub and tall ruderal vegetation, as well

as hard standing and sparsely vegetated areas. This area would be the subject of

a landscaping scheme which would include the creation of habitats of high nature

conservation value such as species-rich grassland and open mosaic habitats.


11.6.64 As a consequence, the construction of the proposed HWRC would alter the

ecological baseline on the Site. With respect to the earthworks to the south of the

Existing Station, there is no significant difference in terms of habitat loss, since the

area would be utilised for material excavated as part of the construction of the

Existing Station (see Figures 5.8e - 5.8h). However, loss of vegetation on the

eastern bund represents an additional effect attributable to the HWRC.

11.6.65 As described in Chapter 5.0, the earthworks that would be carried out prior to the

construction of the Proposed Extension would need to accommodate the

additional material excavated to construct the HWRC. As such the height of the

proposed earthworks along the western perimeter of the Site would be 5m higher

in the HWRC Scenario (refer to Figures 5.4a-5.4f for an illustration of this).

Grid Connection

11.6.66 As set out in Chapter 5.0, the connection to the local electricity grid would be

undertaken by the District Network Operator (DNO) under their statutory powers

under the Electricity Act 1989. These works would be brought forward separately

by the DNO and as such do not fall to be consented under the DCO process.

Nonetheless, the Chapters of the PEIR have considered the likely environmental

impacts associated with the installation of the Grid Connection, because the

connection to the network is a critical requirement for the Proposed Extension to

recover energy.

11.6.67 The Existing Station is connected to the Maidstone Sub-Station via an

underground connection that runs east around the 20/20 Business Park and then

south through a variety of land-uses and suburban areas to the north of

Maidstone (Route A). The existing grid route is subject to a number of potential

environmental and physical constraints, which has led the Applicant to consider

whether an alternative route may be preferable (Route B). Accordingly, there are

two potential grid connection routes for the Proposed Extension, as follows:

• Route A: the grid route from the Existing Station, running through undeveloped

and suburban areas towards the northern edge of Maidstone;

• Route B: an alternative route that follows the A20, and roads passing through

Maidstone town centre.


11.6.68 The potential grid routes are shown on Figure 4.1. This assessment will consider

the potentially significant environmental effects associated with construction /

decommissioning and operation of both routes on ecology.

11.7 Assessment of Effects

Incorporated Mitigation

Scheme Design

11.7.1 Mitigation measures incorporated into the design of the Proposed Extension are set

out in the Scheme Description (Chapter 5.0); measures relating to air quality are

set out in Chapter 13.0.

Measures to Avoid Effects on the Water Environment

11.7.2 Measures will be incorporated into the construction and operational phase of the

Proposed Extension to avoid effects on the water environment. These include

measures to address both water quantity (i.e. changes in runoff characteristics) and

water quality (i.e. avoidance of pollution). Additional mitigation measures are set

out in Chapter 12.0 and discussed in more detail below. These will have the effect

of avoiding or reducing risks to important ecological features such as the River

Medway.

Measures to Reduce Noise Disturbance

11.7.3 Measures to reduce noise generation during the construction and operational

phases of the Proposed Extension are outlined in Chapter 14.0 (Noise and

Vibration). Note that no noise-sensitive ecological receptors have been identified in

close proximity to the Site.

Measures to Maintain / Enhance Habitats on Site

11.7.4 The landscape design of the Proposed Extension has been developed as part of an

iterative process between the Project landscape architect and ecologist. The aim of

this process was to maximise the biodiversity value of retained and restored

habitats within the Site, while achieving the landscape design objectives set out in


Chapter 10.0. The indicative Landscape Proposals are set out on Figure 9.6a

Illustrative Landscape Masterplan (without HWRC) and Figure 9.6b Illustrative

Landscape Masterplan with HWRC.

11.7.5 A total of over 15ha of habitats will be restored on Site, including broadleaved

plantation, neutral grassland, scrub, open mosaic habitat and a small orchard. A

further area of 7ha will be retained, situated to the north and north-east of the

Existing Station, and including most of the Lowland Mixed Deciduous Woodland

priority habitat.

11.7.6 In terms of Biodiversity Metric 2.0, retained, enhanced and created habitats within

the Site will have a value of 191.95 biodiversity units, including habitat creation in

the landscape design of 93.76 biodiversity units. Further details are provided in

Appendix 11-12.

11.7.7 In the HWRC scenario retained, enhanced and created habitats within the Site will

have a value of 181.71 biodiversity units, including habitat creation in the

landscape design of 102.27 units. This lower value is a consequence of the higher

weighting given to retention over restoration in the Biodiversity Metric 2.0

methodology and is a consequence of the additional habitat loss on the eastern

bund. Further details are provided in Appendix 11-13.

11.7.8 Both of the metric calculations have been included as Appendices 11.12 and

11.13. However, reference should be made to the source spreadsheets to explore

the basis for these calculations.

Measures to avoid Air Quality Effects

11.7.9 Mitigation of air quality effects has been developed through an iterative process

involving the Project air quality assessors and ecologists, after identification and

confirmation of sensitive ecological receptors and consideration of the results of the

Stack Height Assessment.

11.7.10 Incorporated mitigation measures involve an increase in the existing stack height

from 80m to 90m to aid dispersion, and combination of the emissions from the

Existing Station with the Proposed Extension into a single stack to increase


buoyancy. These measures have the effect of reducing the process contribution of

the Proposed Extension to negligible levels at the North Downs Woodlands SAC;

this has implications for the Habitats Regulations Assessment (HRA) process

which are discussed in the Appendix 11-8.

Assessment of Construction Phase Effects - Existing Scenario

Potential Impacts

11.7.11 Key potential impacts during the construction phase of the Proposed Extension

include:

• Land-take for construction, with consequent loss of habitats and component

species in those parts of the Site which lie within the development footprint,

earthworks or construction laydown area;

• Potentially increased risk to water environment from loss of vegetation /

increase in runoff from bare surfaces, leakage of hydrocarbons from plant and

vehicles, and / or contamination from stored fuel or other materials; and

• Increased noise, lighting, vehicle movements and human activity as a

consequence of construction works, with potential disturbance of species using

proximal habitats.

Effects of Land-take

11.7.12 The need to carry out extensive earthmoving operations within the Site to

accommodate the Proposed Extension means that most vegetated habitats will be

lost. Calculations of volumes and the spatial extent of these earthworks are set out

elsewhere in this PEIR.

11.7.13 There will be some retention of habitats, including:

• An area in the central part of the northern bund surrounding the Existing

Station;

• An area in the far northern and north-eastern part of the Site adjoining the M20,

which includes Lowland Mixed Deciduous Woodland priority habitat;

• The main part of the wetland in the western part of the Site will be retained,

although its surroundings will be altered with steeper gradients;

• The small settlement pond adjoining the Existing Station, together with some

areas of amenity grassland around the buildings;


• The eastern bund surrounding the Existing Station; and

• The southern slope of the wooded bund adjoining the access road on the

southern boundary of the Site.

11.7.14 A calculation has been made of the value of habitats lost in biodiversity units using

Biodiversity Metric 2.0. The principles of the assessment methodology and a

summary of the results of the calculations set out in Appendix 11-12. Based on the

anticipated extent of the proposed earthworks, this equates to a total of 162.85

habitat units (see Appendix 11-12, Table 1). This value does not provide a

qualitative evaluation of habitat loss, but does provide a numeric value in

‘biodiversity units’ against which the value of mitigation works can be measured.

11.7.15 Removal of plantation woodlands, scrub and tall vegetation (e.g. tall ruderal

habitats, bramble under-scrub) is likely to affect breeding birds if undertaken during

the breeding season; few species were recorded in the survey likely to breed in

open grassland habitats, although there are few areas which do not support

scattered scrub. Without appropriate mitigation measures to avoid killing or injury

there is a risk of contravening protected species legislation. There are no significant

risks to other legally protected species as a consequence of the site clearance

process.

Areas of relatively species-rich grassland containing orchid populations are also

within the earthworks footprint. The evaluation in Appendix 11-2 notes that these

areas do not qualify as Lowland Meadows Priority Habitat, although they contribute

to the Site’s overall biodiversity interest, and are identified as a feature of local

importance in Table 11.5. Mitigation proposals for these areas are set out in

section 11.9 below.

Risks to Water Environment

11.7.16 There is an increased potential for effects on the water environment during the

construction phase. The Proposed Extension does not involve working in close

proximity to existing watercourses, although its location around 300m from the

River Medway requires a precautionary approach to be taken to the management

of construction phase risks, both in relation to construction of the Proposed

Extension and associated earthworks.


11.7.17 Additional mitigation measures are contained within the draft CEMP (Appendix 5-

4). These would help avoid risks of inadvertent pollution of watercourses during the

construction phase. It is intended that this would require approval through a DCO

Requirement prior to the commencement of development.

11.7.18 Retention of the pond area in the western part of the Site would preserve its

functionality as a groundwater-dependent terrestrial ecosystem (GWTE), although

its ecological value would be reduced through replacement of peripheral scrub and

ephemeral – short perennial vegetation of the quarry floor with more steeply graded

grassland slopes.

Increased Disturbance During Construction

11.7.19 The construction phase of the Proposed Extension has the risk of causing more

intensive disturbance of wildlife than its subsequent operational phase, although

individual disturbance events will generally be relative short in duration. Examples

include site clearance and earthmoving, and construction operations involving the

use of heavy equipment. Increased human activity, noise and the use of temporary

security lighting all have the potential to cause temporary disturbance of wildlife.

11.7.20 The Proposed Extension would be developed adjacent to the Existing Station, the

20/20 Business Park, and major road and rail infrastructure. The nearest habitats

which could be considered as sensitive receptors to construction phase

disturbance are the ancient woodland habitats adjoining the Medway. However,

these are separated from the Site by the M20 motorway, to which they are also in

close proximity to. Therefore, it is reasonable to concluded that on the basis of

these factors the Proposed Extension is unlikely to give rise to a significant effect

as a consequence of increased disturbance during the construction phase.

Assessment of Decommissioning Phase Effects – Existing Scenario

11.7.21 It is unclear at what point decommissioning and demolition of the Proposed

Extension would occur and what changes there would be in methods and approach

to decommissioning facilities in the intervening period. Notwithstanding, this could

be a part of the Project and so it is necessary to consider whether this would have

the potential to give rise to likely significant effects.


11.7.22 Because of the uncertainty regarding the timing and approach to decommissioning,

for the purpose of this assessment, it has been assumed that similar techniques

and / or approaches would be used as the construction phase.

11.7.23 Whilst similar techniques would be used, the ecological impacts during the

decommissioning phase could differ from those experienced during the

construction phase. The construction phase would involve significant earthworks

which would result in the loss of retained habitat around the Existing Station. Whilst

decommissioning could relate to the extended Generating Station in its entirety, it is

likely that this would be limited to the buildings and hardstanding areas and the

landscape / biodiversity enhancement areas that are proposed in connection with

the Proposed Extension would be retained. In light of this, it is reasonable to

assume that the decommissioning effects on ecology would at worst be similar to

those experienced during the construction phase (none of which have been

identified as significant in EIA terms) and are, in all probability, likely to be less than

those predicted during construction.

Assessment of Construction / Decommissioning Effects - HWRC Scenario

11.7.24 In this scenario, the operational effects of the HWRC in terms of noise, vehicle

movements and human disturbance have the potential to act in a cumulative

manner with construction phase disturbance caused by the Proposed Extension.

This activity would be located close to the Site’s eastern boundary, where there is

already a high level of human disturbance from an adjoining distribution centre and

can be considered a low-sensitivity receptor. There will therefore be no significant

difference between construction-phase disturbance in this scenario.

11.7.25 The presence of the HWRC will not increase the construction-phase risk to the

water environment, as it would have its own systems to control and contain surface

water runoff and prevent pollution. These will be unaffected by development of the

Proposed Extension.

11.7.26 The deposition of excavated material in the western part of the Site from the

HWRC would produce a requirement to raise levels of earthworks relative to the

Proposed Extension, but will not significantly alter the spatial extent of disturbance,

or require significant changes to restoration proposals.


11.7.27 A calculation has been made of the value of habitats lost in biodiversity units using

BM 2.0. The principles of the assessment methodology are set out in Appendix

11-2, and a summary of the results of the calculations set out in Appendix 11-13.

This takes into account the additional area of habitat loss within the development

footprint of the HWRC, and equates to a total of 180.36 habitat units. This

provides a slightly higher target for habitat creation and enhancement works when

compared to the total of 162.85 calculated for the Proposed Extension alone.

Assessment of Construction and Decommissioning Effects of Grid

Connection

11.7.28 As stated in Section 11.6 above, two potential grid connection routes are being

considered for the Proposed Extension (Route A and Route B). The route options

are illustrated on Figure 4.1. This section assesses the potential construction and

decommissioning phase impacts each route would have on ecology.

11.7.29 The existing grid connection route (Route A) passes through or close to some

areas of significant nature conservation interest. This can be illustrated by a

comparison of Figure 4.1 with Appendix 11.1, Figure A11.1.2.

11.7.30 After leaving the Site and passing under the Maidstone – Strood rail line, the route

runs parallel to a tidal reach of the River Medway, which lies within the Medway

MCZ. It then passes close to the boundary of an ancient woodland, Lock Wood,

before a directionally-drilled crossing of the River Medway upstream of the tidal

limit and MCZ.

11.7.31 Continuing to the east of the A229, the route passes close to Cuckoo Wood LWS

and ancient woodland, although separated from it by a minor road (Sandling Lane).

After continuing within and adjacent to public highways, the route then passes

through the southern edge of Heath Wood, a woodland located to the south-west of

M20 junction 7. The section of woodland on the southern boundary is classed as a

Plantation on Ancient Woodland (PAWS) site.

11.7.32 The route then turns south, across the A249 and through Upper Fullingpits Wood;

this is not on the Ancient Woodland Register, although the nearby Lower Fullingpits

Wood to the east is classed as ancient semi-natural woodland. The remainder of

the route continues on a generally southerly trajectory through urban areas to the

grid connection at Maidstone 132/33kV Substation.


11.7.33 As well as the sites of known ecological interest, the route passes through public

open spaces and parkland either side of the River Medway (Allington Open Space

and a recreation ground at Dickens Road), as well as open space with mature trees

within the Invicta Park complex.

11.7.34 It is understood that a new grid connection along the existing Route A would

require a new route separated by up to 6m from the existing cable duct. It would

not be possible to use the existing duct and may therefore not be possible to avoid

nearby features of ecological value.

11.7.35 Route B reaches the Substation through urban areas of Allington and Maidstone. It

crosses the River Medway on an existing road bridge and does not pass close to

any features of known ecological interest. It is located either within road surfaces,

verges or paths, and avoids any areas of woodland or other semi-natural

vegetation. There are some street trees within road verges along parts of the route

which may justify protection or avoidance measures, but do not constitute

significant ecological constraints.

11.7.36 In light of the foregoing, Route B can be regarded as a preferred option in

ecological terms, as it avoids any features which may have any biodiversity

interest.

Decommissioning of Grid Connection

11.7.37 At the end of its operational life, it is anticipated that the ducting for the Grid

Connection would be left in situ, such that there would be no decommissioning

works and therefore no potential significant effects upon ecological interest features

adjoining the route.

Assessment of Operational Phase Effects – Existing Scenario

Potential Impacts

11.7.38 Key potential impacts during the operational phase of the Proposed Development

include:

• Potential air quality effects of emissions on sensitive ecological receptors,

including statutory designated sites;


• Potential near-site effects of noise, human disturbance and lighting.

Air Quality Effects

11.7.39 The following provides a summary of the key impacts in relation to Environment

Agency or IAQM screening thresholds8.

11.7.40 In all cases, the Proposed Extension results in an increase in nitrogen and acid

deposition rates of less than 1% of the relevant Critical Load for the most sensitive

habitat present, relative to the existing baseline.

11.7.41 At North Downs Woodland SAC, the process contribution (PC) to nitrogen

deposition is predicted to be a maximum of 0.8% of the lower Critical Load for the

most sensitive woodland plant community present. The PC to acid deposition is

0.5% of the relevant Critical Load, and ammonia levels are predicted to increase by

0.8% of the relevant Critical Level.

11.7.42 At ancient woodlands and Local Wildlife Sites, the process contribution to nitrogen

deposition is predicted to be between 0.1 and 0.3% of the lower Critical Load for

the most sensitive habitat present; the PC for acid deposition is predicted between

0.1 and 0.6% of Critical Load. Lock Wood ancient woodland has a predicted

reduction in PC of -0.8% with respect to nitrogen deposition, and -2.1% with

respect to acid deposition.

11.7.43 The ecological effects of emissions to air are addressed in more detail in Appendix

11-6, based on the Emissions Modelling Report produced by Fichtner Consulting

Engineers (Appendix 13-3). In addition to the above impacts, and following

consultation with Natural England, in-combination effects of nitrogen deposition in

North Downs Woodlands SAC are also considered in the Habitats Regulations

Assessment Report Appendix 11-7.

8 Holman et al (2019). A guide to the assessment of air quality impacts on designated nature conservation sites – version 1.0, Institute of Air Quality Management, London. www.iaqm.co.uk/text/guidance/airquality-impacts-on-nature-sites-2019.pdf

http://www.iaqm.co.uk/text/guidance/airquality-impacts-on-nature-sites-2019.pdf


Potential Effects of Noise, Human Disturbance and Lighting

11.7.44 As noted in the assessment of effects during the construction phase, there are few

important ecological features around the Site which could be regarded as

particularly noise sensitive.

11.7.45 The increase in operational phase traffic movements within and around the Site

compared to the current baseline is relatively low (see Chapter 15.0), and does not

significantly alter the likelihood of disturbance of adjoining habitats.

11.7.46 There are few receptors of high sensitivity to increased light levels in the vicinity of

the Proposed Extension, as evidenced by data from the bat survey. The Existing

Station is illuminated, and lighting on the adjoining motorway and dual carriageway

road network means that any increase in lighting will be incremental in extent,

rather than introducing lighting into a previously dark natural environment.

Effect Significance

11.7.47 The table below combines the identification of important ecological features,

including their geographic scale of importance, with the potential impacts and their

predicted effects set out above. It uses these to assess the effect on the

conservation status of species, and the integrity of any sites or component habitats

thereof, in order to identify whether any ecological effects can be considered to be

significant in EIA terms.

11.7.48 With respect to designated sites in the defined Study Area of the Proposed

Extension, no ecologically significant construction phase effects are predicted.

Additional mitigation measures set out in the Water Quality and Drainage section

and incorporated in the CEMP will ensure avoidance of any risks on the River

Medway and Medway MCZ and ensure that there are no significant effects.

11.7.49 With the implementation of incorporated mitigation measures, operational phase air

quality effects on designated sites are all predicted to be negligible in magnitude

(i.e. below Environment Agency or IAQM screening thresholds). The design and

operation of surface water attenuation features will ensure continuing avoidance of

risk to the River Medway and Medway MCZ.


Table 11.6: Effect Significance

Interest feature Scale of

importance Effects

Effect significance / effect on site integrity or conservation status

Off-Site Interest Features: Construction / Decommissioning Phases

River Medway / Medway MCZ County /

national level

Risk of effects reduced to negligible level or avoided by measures set out in

Water Quality and Drainage chapter and CEMP

No predicted effects

All other sites International –

local

Can be screened out from further assessment – all more than 50m from Site boundary and with no predicted

effect pathway


Off-Site Interest Features: Operational Phase

North Downs Woodlands SAC

International

With incorporated mitigation, inconsequential (de minimis) increase in nitrogen deposition rates, alone and in-combination with road traffic effects

No effect on site integrity

Ditton Quarry LNR

County level

Air quality effects all below screening

thresholds No other predicted effects

No significant harm

River Medway / Medway MCZ

County / National level

Design of surface water attenuation features avoids risk of effects on water

environment No predicted effects

Aylesford Old Pit LWS County level

Air quality effects all below screening thresholds

No other predicted effects No predicted effects

Cuckoo Wood LWS County level



Blue Bell Hill Banks and Verges LWS County level



Lock Wood Local



Sandling Wood

Local

Air quality effects all below screening thresholds; small magnitude reduction in acid deposition rates (minor positive

magnitude) No other predicted effects


Dog Kennel Wood Local



Broke Wood Local



Fullingpits Wood Local



On Site Interest Features: Construction Phase


Local Proximal disturbance impacts of

earthmoving Minor negative effect, not significant in EIA terms


Interest feature Scale of

importance Effects

Effect significance / effect on site integrity or conservation status

Neutral grassland habitat (relatively species-rich areas with orchids)

Local Loss of feature

Minor negative effect at local scale, requires

additional mitigation not significant in EIA terms


Local Partial loss / disturbance of feature

with groundwater-dependent habitats retained

Minor negative effect at local scale, not significant

in EIA terms

Peregrine Falcon Local (legal protection)

None predicted Not significant

Breeding bird assemblage Within-site

(legal protection)

Possible damage or destruction of nests, eggs and dependent young during site clearance operations

No significant effect on local population / will require mitigation to maintain legislative

compliance

On-site Interest Features: Operational Phase


Local Adjoining planting in new landscape design will increase effective area of

woodland as it matures

Minor positive, not significant

Neutral grassland habitat Local

New grassland habitats will develop, species composition and diversity

depending on management

Minor positive effect, greater with mitigation


Within-site Parts of feature retained, including

open water / emergent vegetation, but constrained by adjoining steep slopes

Not significant

Peregrine Falcon Local

No significant change from current baseline

Not significant

Breeding bird assemblage Within-site

Likely to see recovery in breeding density (within 5 years) as restored

habitats mature Not significant

Grid Connection

11.7.50 As noted previously, the electrical grid connection would comprise an underground

cable. Accordingly, during the operational phase, it would not have any potential to

give rise to significant effects on ecology.

Assessment of Operational Phase Effects - HWRC Scenario

11.7.51 The HWRC would result in an increase in noise and human disturbance in the

vicinity of the Existing Station, through development of the eastern bund. This will

be proportionately more disturbing to birds and other wildlife using the Site than

either the Existing Station or the Proposed Extension, because of the greater

frequency of outdoor human activity, vehicle movements and noise associated with

disposal of household waste. In contrast, despite movement of HGVs to and from

the Tipping Hall, in normal operation an energy recovery facility usually


experiences relatively little outdoor human activity. However, as noted in the

context of construction-phase disturbance, this activity would be located close to

the Site’s eastern boundary, where there is already a high level of human

disturbance from an adjoining distribution centre. It will not significantly affect the

ability of wildlife to colonise and utilise the restored landscape around the Proposed

Extension, which is separated from the HWRC by the Existing Station. It will not

therefore result in a significant difference in the significance of operational phase

ecological effects.

11.8 Cumulative Effects

11.8.1 As described in Chapter 6, the cumulative assessments undertaken within each

chapter of this PEIR has been carried out by considering which scenario (i.e.

development of the Proposed Extension with or without the HWRC) would give rise

to the ‘worst-case’ for the assessment of that environmental topic. Once that has

been established, it has then been assessed on that basis in conjunction with the

cumulative schemes set out below. Where the two scenarios give rise to different

worst-case effects, two cumulative scenarios are assessed separately.

11.8.2 For the purposes of the assessment of potentially significant effects on ecology, it

has been judged that the ‘HWRC Scenario’ would represent the worst case. This is

on the basis of a slightly greater effect volume of traffic generation. This relates

principally to the ecological effects of emissions to air, which have been modelled

in Appendix 13-4. It must be noted that even with slightly greater effects these

would still not be significant in EIA terms.

11.8.3 The approach to the cumulative assessment is discussed in Chapter 6.0. All six

identified developments are for residential use; three benefit from planning

permission (not yet implemented), whilst the planning applications for the other

three have not yet been determined. The schemes are listed below, and their

locations are shown on Figure 6.1.

11.8.4 The following projects are considered in the assessment of cumulative effects:

• Springfield Road, Maidstone – 295no. residential units;

• Somerfield Distribution Centre, Aylesford – 92 no. residential units;


• Land W of Hermitage Road / E of Quarry Wood Industrial Estate, Aylesford –

total of 99no. residential units including assisted living spaces;

• Springfield Library, Maidstone – 170 no. residential units;

• Land S of London Rd. / E of Hermitage Lane, Aylesford – 840 no. residential

units and associated services;

• Land SW of London Rd. / W of Castor Park, Allington – 106 no. residential

units.

11.8.5 With the exception of traffic generation, there are no potential effects of the above

developments which could operate in combination with the Proposed Extension.

None adjoin the Site or are ecologically linked to it, so habitat losses associated

with them would not act in a cumulative manner through severance of ecological

networks. The Proposed Extension will not give rise to additional recreational

pressure on sensitive sites, so cannot act in a cumulative manner with residential

developments. Aside from traffic, none of the above developments include sources

of emissions to air.

11.8.6 Cumulative effects of road traffic generation for the above are considered in

Chapter 13.0 (air quality) Emissions modelling has concluded that there will be no

significant cumulative effects as a consequence of traffic and point source

emissions from the Proposed Extension in combination with the above

developments.

Other Cumulative Effects - North Downs Woodland SAC

11.8.7 The Emissions Modelling report (Appendix 13-3) considers a range of plans and

projects which may result in road traffic-related air quality impacts on North Downs

Woodland SAC.

11.8.8 A Habitats Regulations Assessment (HRA) Report assesses the implications of

these cumulative effects for the integrity of the SAC, with the conclusion that there

is no exceedance of Environment Agency or IAQM screening thresholds, and in-

combination effects can be considered negligible in EIA terms, and inconsequential

or de minimis in HRA terms.


11.9 Additional Mitigation

Mitigation for Construction Phase Effects on Water Environment

11.9.1 Additional mitigation measures to avoid effects on the water environment are set

out in Section 12.8 of the Water Quality and Drainage chapter of the PEIR.

Measures can be summarised as:

• Provision of a CEMP;

• Conformity of construction works to ADAS Technical Note on Workmanship

and Materials for Drainage Schemes (1995);

• Earth moving operation would be undertaken in accordance with BS6031:2009

Code of Practice for Earthworks;

• Conformity with DEFRA guidance in the Construction Code of Practice for the

Sustainable Use of Soils on Construction Site (2009);

• Good practice guidance on erosion and pollution control would be followed, e.g.

CIRIA Environmental Good Practice on Site (C692) and Control of Water

Pollution from Construction Sites (C532);

• Avoid the storage of plant / machinery fuel or material (including soil stockpiles)

alongside watercourses unless unavoidable. Construction works should be

programmed as far as is practicable to minimise soil handling and temporary

soil storage; and

• Spillage prevention and remediation measures including designated refuelling

areas, bunded and locked tanks, and spill kits.

Mitigation for Construction Phase Effects on Grassland Habitats

11.9.2 The boundaries of areas of relatively species-rich grassland containing orchid or

broomrape (Orobanche minor) populations identified in the extended Phase 1

Habitat Survey will be plotted using a sub-metre mapping grade GIS.

11.9.3 Soils from these areas will be stripped and re-spread as part of the progressive

restoration of the Site. Because of the phasing of the earthmoving works, it will be

possible to strip and spread these soils in one operation, minimising handling and

avoiding storage. This will serve to avoid any loss of seed viability, and minimising

loss of viability of vegetative propagules in the upper soil horizons.


11.9.4 Soils from these areas will, wherever possible, be reserved for areas to be

managed as grassland in the new landscape design, rather than woodland.

11.9.5 A draft CEMP has been prepared in support of this PEIR and is contained within

Appendix 5-4, this sets out the approach to earthworks movements generally and

in terms of the specific requirements for the retention of orchids.

Avoidance of Construction Phase effects on Proximal Habitats

11.9.6 A site perimeter fence would be erected during earthworks to ensure that proximal

habitats which lie outside the development footprint are appropriately protected.

This will include, in particular, the area of Lowland Mixed Deciduous Woodland

Priority Habitat located on the northern / north-eastern boundary of the Site.

Construction Phase Mitigation for Breeding Birds

11.9.7 Site clearance of scrub vegetation and other tall cover will not be undertaken within

the bird breeding season (March – end August), if necessary, bringing forward such

advance works in advance of the main construction period.

11.10 Residual Effects

11.10.1 The table below summarises the residual construction phase ecological effects of

the Proposed Extension following implementation of mitigation measures. Note

that there are no differences in significance between the Proposed Extension and

the HWRC scenario. This excludes effects which have been avoided by

incorporated mitigation measures and focusses on those identified in Table 11.6.


Table 11.7: Residual effects – construction phase

Interest feature

Scale of Importance

Predicted Effect

Significance of Effect; Pre-mitigation

Mitigation Residual Significance of Effect

Medway MCZ / River Medway

National / County level

Pollution risk

Negligible (see Table 12.9)

Operational control and monitoring measures in CEMP

Negligible


Local Physical disturbance

Minor negative, not significant in EIA terms

Fencing and avoidance measures

Negligible

Neutral grassland (orchid-rich areas)

Local Loss of feature

Minor negative, local scale

Preservation of surface soils

Minor negative, becoming negligible

Wetland habitats

Local Loss of marginal habitats

Minor negative, not significant in EIA terms

Limitation of damage to core wetland through measures in CEMP

Minor negative, nto significant in EIA terms

Breeding bird assemblage

Within-site

Disturbance / damage to nests and young

Negligible, but legal protection requires mitigation

Clearance of suitable breeding habitat outside nesting season

Negligible

11.10.2 The table below considers residual operational phase effects.

Table 11.8: Residual effects – operational phase

Interest feature

Scale of Importance

Predicted Effect

Significance of Effect; Pre-mitigation

Mitigation Residual Significance of Effect

North Downs Woodlands SAC

International Air quality effects

Negligible (with incorporated mitigation)

No additional mitigation necessary

Negligible

Medway MCZ / River Medway

National / County level

Pollution risk

Negligible (see Table 12.10)

Surface water drainage strategy

Negligible

11.11 Compensation for Construction Phase Habitat Loss

11.11.1 The Construction of the Proposed Extension to the Allington IWMF would result in

the loss of an area to the west of the Existing Station, that currently comprises the

restored former Allington Quarry. This land is identified within the existing Allington


S106 agreement (dated 13th November 2017) as a NCA. The NCA does not have

any statutory or non-statutory designation and does not met the Kent Selection

Criteria for a LWS.

11.11.2 The NCA would be lost in its entirety during the construction phase of the Proposed

Extension and, following completion of construction, the land that remains to the

west of the Proposed Extension would be restored providing ecological, landscape

and amenity benefit (See Figures 9.6a and 9.6b).

11.11.3 Habitat loss associated with the construction of the Proposed Extension has been

identified within this Chapter of the PEIR and it has been concluded that, taking into

account the proposed mitigation measures (soils handling and placement,

avoidance of effects on priority habitats and partial restoration) the works would

result in an effect of minor significance at a local scale of importance and are not

significant in EIA terms. Whilst an adverse effect, additional ecological measures

are not required to compensate for the loss.

11.11.4 Notwithstanding, following discussion with KCC, the Applicant chose to develop a

strategy that would aim to off-set the loss of biodiversity arising from the

development of the Proposed Extension by means of on-site mitigation and off-site

compensatory habitat enhancement (see Appendix 11-9). Biodiversity Metric 2.0

provides a tool to quantify the value of this enhancement, set against the value of

habitats lost.

11.11.5 The Applicant has identified an area of land within the same local authority

(TMBC), which is under their ownership and control, where enhancement

measures could be undertaken to compensate for the loss on the Allington Site.

That site is the former Stangate landfill, which is located near Borough Green,

Kent. Details of the proposed enhancement measures are set out in the Stangate

East / West and Stangate East Ecological Management Plans, contained within

Appendices 11-10 and 11-11.

11.11.6 Biodiversity Metric 2.0 has been used to calculate the net gain from the Proposed

Development (see Appendix 11-2 for further details). The Metric calculation has

confirmed that the Stangate East / West Ecological Management Plan could deliver

a net gain of up to 56.69% (52.41% in the HWRC Scenario) and that the Stangate


East Ecological Management Plan could deliver a net gain of up to 9.99% (5.71%

in the HWRC Scenario)

11.12 Summary

11.12.1 The Proposed Extension will result in the development of land at Allington IWMF

currently subject to a Section 106 Agreement and managed as a Nature

Conservation Area. Following ecological surveys, the nature conservation value of

this area has been evaluated, together with habitats around the Existing Station

which make up the Site. The conclusion of this assessment is that it would not

currently meet Kent Local Wildlife Site criteria, although it does contain features

with some biodiversity interest. These include areas of grassland supporting

populations of locally common orchid species, and a remnant area of longer-

established woodland adjoining the M20 motorway.

11.12.2 Ecological surveys have found relatively low levels of bat activity on the Site;

surveys for great crested newts, reptiles and other protected species produced

negative results. The invertebrate fauna comprises relatively mobile species,

typically occurring in relatively immature habitats. These results have been

interpreted as arising from the isolation of habitats by transport infrastructure and

industrial development and by the Site’s history of disturbance.

11.12.3 Mitigation measures are planned to protect woodland and provide partial protection

to wetland habitats during construction, and to identify areas of soils supporting

areas of relatively species-rich grassland. These soils will be utilised in the

restoration of new grassland habitats in the Site’s landscape design.

11.12.4 With respect to off-site habitats, North Downs Woodlands SAC has been identified

as a sensitive receptor of high nature conservation importance with respect to

emissions to air. Mitigation measures have been incorporated into the design of the

Proposed Extension to ensure that dispersion and deposition of key pollutants

remains below Environment Agency and IAQM screening thresholds, alone and in

combination with other plans and projects. Consequently, no effects on the

integrity of European and internationally designated conservation sites are

predicted as a consequence of the Proposed Extension.


11.12.5 The River Medway, including the Medway MCZ in the tidal reaches of the river, has

been identified as a sensitive receptor for water quality impacts. Mitigation

measures during construction, operation and decommissioning of the Proposed

Extension are set out in the Water Quality and Drainage section (Chapter 12.0).

These will have the effect of avoiding any risk to the water environment or reducing

risk to a level which can be considered negligible.

11.12.6 The HWRC scenario will result in an additional impact on habitats to the east of the

Existing Station, but does not change the significance of ecological effects, or

impose any significant constraints on proposed mitigation measures.

11.12.7 The assessment indicates that the Proposed Extension would not have a

significant residual effect on important ecological features, subject to the

implementation of mitigation measures. It is also possible to achieve biodiversity

net gain in excess of 10% of baseline values through the implementation of off-site

habitat enhancement works at the former Stangate landfill site.

11.12.8 The proposal complies with policy NPS EN-1 in avoiding significant harm to

ecological resources, including through the incorporation of mitigation measures

into the design of the Proposed Extension. Opportunities will be taken to create

new habitats of value within the Site’s restored landscape.

11.0 ecology and nature conservation11-1€¦ · 11.0 ecology and nature conservation 11.1...

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