Relocation of Hillingdon Outdoor Activities Centre to New Denham Quarry including an extension to the mineral working area

Transcription

1 Relocation of Hillingdon Outdoor Activities Centre to New Denham Quarry including an extension to the mineral working area Volume 2 Non-technical summary May 2016 CS525B

2 Relocation of Hillingdon Outdoor Activities Centre to New Denham Quarry including an extension to the mineral working area Volume 2 Non-technical summary May 2016 CS525B

3 High Speed Two (HS2) Limited has been tasked by the Department for Transport (DfT) with managing the delivery of a new national high speed rail network. It is a non-departmental public body wholly owned by the DfT. A report prepared for High Speed Two (HS2) Limited acting as Agent for the Hillingdon Outdoor Activities Centre (HOAC): High Speed Two (HS2) Limited, One Canada Square, Canary Wharf, London E14 5AB Telephone: General enquiries: HS2enquiries@hs2.org.uk Website: High Speed Two (HS2) Limited has actively considered the needs of blind and partially sighted people in accessing this document. The text will be made available in full on the Buckinghamshire County Council Planning Portal website. The text may be freely downloaded and translated by individuals or organisations for conversion into other accessible formats. If you have other needs in this regard please contact High Speed Two (HS2) Limited. High Speed Two (HS2) Limited, 2016, except where otherwise stated. Copyright in the typographical arrangement rests with High Speed Two (HS2) Limited. This information is licensed under the Open Government Licence v2.0. To view this licence, visit version/2 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or psi@nationalarchives.gsi.gov.uk. Where we have identified any third-party copyright information you will need to obtain permission from the copyright holders concerned. Printed in Great Britain on paper containing at least 75% recycled fibre.

4 Contents 1 Introduction The proposed development Scoping Report Consultation and engagement Environmental impact assessment and Environmental Statement Cumulative effects Significant residual effects 7 2 Scheme description Site Description Proposed development description 12 3 Construction and operation Construction overview Alternative Locations 18 4 Preparation of the Environmental Statement 19 5 Environmental Summary Introduction Agriculture, forestry and soils Air Quality Community Cultural heritage Ecology Land quality Landscape and visual assessment Sound, noise and vibration Traffic and transport Waste and material resources Water resources and flood risk 30 6 Glossary 37 List of figures Figure 1: Application boundary 8 Figure 2: Site context plan 10 Figure 3: Approved restoration Scheme (including Phase 4C, CM/32/14) 11 3

5 Figure 4: Illustrative masterplan 14 Figure 5: Graphic description of the Stages required as part of construction and operation of the proposed development 16 Figure 6: Environmental impact assessment process diagram 19 List of tables Table 1: Summary of likely significant effects 32 4

6 1 Introduction Volume 2 Non-technical summary 1.1 The proposed development Permission is being sought to extend the present sand and gravel extraction area at New Denham Quarry (the 'application site') and restore the site after the removal of sand and gravel into an outdoor activities centre ('the proposed development'). Hillingdon Outdoor Activities Centre (HOAC) which will be directly affected by Phase One of the proposed High Speed Two rail line between London and the West Midlands (HS2) will relocate to the application site HOAC is currently located at Dews Lane, South Harefield, Middlesex. Whilst it is likely that the site could be used for water based activities following completion of the Hs2 Proposed Scheme, if HOAC were to remain open, the HS2 Phase One Environmental Statement 1 concluded that the land and water used by HOAC would experience significant visual and noise effects affecting the amenity of the facility which would therefore make it unlikely that it could operate during the five year construction period Permission to relocate HOAC is being sought following the publication of the House of Commons Select Committee Second Special Report of Session which recommended HOAC be relocated to the New Denham Quarry site, if HOAC thought it was preferable HOAC have confirmed that in the event that HS2 receives Royal Assent, their preference would be to relocate their facilities to New Denham Quarry and this is the reason that permission is now being sought to enable this to happen The New Denham Quarry site is currently an operational quarry for the extraction of sand and gravel. It is managed and operated by Summerleaze Ltd under lease from Buckinghamshire County Council (BCC) and is subject to an existing approved restoration scheme The extent of the application site is shown in Figure Scoping report A scoping report was submitted with a request for a Scoping Opinion to BCC and South Bucks District Council (SBDC) in December The results of this report concluded that climate change and socio economics were proposed to be scoped out BCC issued a Scoping Opinion incorporating the views of SBDC in April All matters raised in the Scoping Opinion have been addressed in the ES and other accompanying application documents. 1 HS2 Phase One Environmental Statement available online at 2 High Speed Rail (London-West Midlands) Bill: Second Special Report of Session page 52 Para 199) 5

7 1.3 Consultation and engagement Consultation with relevant stakeholders has been ongoing throughout the planning application process. Two community pre-application consultation and engagement events have been held as follows: Hillingdon Outdoor Activities Centre, Dews Lane, Harefield, Middlesex UB9 6JN on Saturday 19 March, from 11am to 3pm; and New Denham Community Centre, Oxford Road, Uxbridge, UB9 4DW on Saturday 9 April from 11am to 3pm. 1.4 Environmental impact assessment and Environmental Statement The Environmental Impact Assessment (EIA) undertaken has assessed the likely significant environmental effects as a result of the proposed development. The findings of the EIA are presented in the Environmental Statement (ES) that accompanies the planning application. The ES consists of five volumes as follows: Volume 2 (this volume): Non-Technical Summary; Volume 3: Main Environmental Statement; Volume 4: Environmental Statement Technical Appendices; Volume 5: Environmental Statement Maps; and Volume 6: Construction Environment Management Plan (CEMP) The Planning Application consists of the following volumes: Volume 1: Planning Statement; Volume 7: Statement of Community Involvement; Volume 8: Design and Access Statement which includes the Sustainability Statement; Volume 9: Flood Risk Assessment (FRA); Volume 10: Drainage Strategy; Volume 11: Site Waste Management Plan (SWMP); Volume 12: Transport Assessment Report; Volume 13: Application drawings: General and Mineral working phases; Volume 14 Application drawings: Landscape drawings; and Volume 15: Application drawings: Architectural drawings This document is Volume 2: Non-Technical Summary (NTS). The NTS provides a summary of the proposed Relocation of Hillingdon Outdoor Activities Centre to New Denham Quarry including an extension to the mineral working area, and its likely significant residual effects on the environment. The NTS summarises those features 6

8 of the design and other measures included in the project in order to avoid, reduce or manage its adverse effects on the environment. Residual effects are those significant adverse and beneficial environmental effects of the project which are likely to remain after those measures are in place The ES has been prepared based on the Town and Country Planning Act Environmental Impact Assessment (EIA) (England and Wales) Regulations 2011 ( the EIA Regulations ) The purpose of an EIA is to identify the likely significant effects of a proposed development on the environment. It does this by identifying the current conditions, anticipating how these may change in the future, and assessing the potential impacts of the development across a range of topics The purpose of this ES is to identify the likely significant environmental effects, recommend mitigation to address any significant adverse effects identified, and identify any significant residual environmental effects which cannot be mitigated. 1.5 Cumulative effects Cumulative effects are those that result from a combination of a number of individual effects. They may result either from a combination of effects arising from the proposed development or from an interaction between the effects of the proposed development with the effects of other reasonably foreseeable developments that are likely to be under construction or to have been completed at the same time. Cumulative effects can be either temporary or permanent For the purposes of this ES committed (approved or permitted development) and potential future developments (submitted or likely to be submitted applications) have been identified through consultation with BCC Amongst the potential future developments most significant is the application Summerleaze Ltd is preparing for an extension of mineral working to the north of the present site (referred to as the 'proposed Northern Extension to New Denham Quarry'). The proposal is for the extraction of sand and gravel from agricultural land immediately north of the existing workings and adjacent to the northern boundary of the quarry. If both applications were successful they would be worked together. Operational quarry traffic would remain the same should both schemes gain consent. Annual rates and volumes of working would be consistent with present operations. The Summerleaze Ltd request for a Screening and Scoping Opinion states that the majority of the land will be restored to form two lakes for recreational and amenity use to create part of the future country park that is the intended after use of the existing quarry. 1.6 Significant residual effects The EIA is required to assess the potential for significant residual effects, i.e. any impacts remaining following implementation of mitigation which are considered to be significant. The significance of residual is defined in accordance with the methodology set out by each topic assessment. 7

9 Figure 1: Application boundary 8

10 2 Scheme description 2.1 Site description New Denham Quarry is located to the south of the A412 Denham Road and to the west of New Denham (refer to Figure 2). There is an access road to the existing quarry site from a roundabout on the A The New Denham Quarry site is currently an operational quarry run by Summerleaze Ltd and is subject to an existing approved restoration scheme (Phase 4C) (refer to Figure 3). Some areas of the quarry site have already been restored as part of this approved restoration plan, including a small lake to the west of the site and a rowing lake to the east of the site The minerals processing works and London Concrete batching plant is located in the north-west corner of the site which will continue to operate throughout the life of the quarry To the east of the site is the Knighton-Way Lane Reservoir, a covered reservoir and foul water pumping station operated by Thames Water. To the south of the site is a National Grid substation at Six Acre Farm. From this substation there are three overhead power lines (OHLs) that cross the site to the north Further infrastructure that runs through the site includes two main sewers and a water main The Rusholt Brook crosses the site from north to south. The River Colne flows along parts of the eastern boundary of the site and the Alder Bourne flows along the south west boundary. The southern part of the site is within the flood plain of the River Colne and the Alder Bourne Field Cottage is a residential dwelling located near the centre of the site, but outside of the application boundary. It is accessed off Knighton-Way Lane and is currently owned by Summerleaze Ltd and used by the Quarry Manager during site operations Four public footpaths are present within or in close proximity to the proposed development The whole of the site is within land designated as Green Belt The existing Summerleaze quarry area is subject to a Bird Management Agreement dated 21st August 2013 due to the proximity of RAF Northolt and London Heathrow. This involves monitoring, scaring and habitat management to minimise the risk of collision risk for passing aircraft as far as reasonably practicable The whole of the site is within the BCC mineral safeguarding area for sand and gravels and a Preferred Area location detailed within the Buckinghamshire Minerals & Waste Local Plan

11 Figure 2: Site context plan 10

12 Volume 2 Non-technical summary Figure 3: Approved restoration Scheme (including Phase 4C, CM/32/14) 11

13 2.2 Proposed development description This proposal involves extending the current quarry site to the north east to include land between the existing quarry and Knighton-Way Lane (refer to Figure 1). A masterplan has been developed and is shown in Figure The proposed development is approximately 68.4ha (169 acres) and consists of: a main central lake of 17.5ha (43 acres) for sailing, windsurfing, canoeing, kayaking and Dragon Boating; an eastern rowing lake (existing) of 7.1ha (17.5 acres) for rowing; a smaller western lake (existing) of 1.4ha (3.5 acres) for amenity and nature conservation; vehicular access using the existing quarry access from the roundabout on the A412 and around the western boundary of the site to a car park at the south of the site. The car park provides 140 spaces in total plus wheelchair accessible spaces located close to the main entrances. A dedicated coach parking and coach/car drop-off zone will also be provided for the safe access of users; outdoor land based facilities for pedal karting, tunnelling, low level ropes, archery, giant swing and high level climbing located between the western lake and the central lake; a range of new buildings as described below; camp site and seasonal staff accommodation (and associated car park - 10 spaces for the camping and 10 for the staff accommodation), low level woodland activities area and open grassed areas located between the eastern lake and central lake; provision of public footpath routes through the site as described below; and provision of a secondary access from Knighton-Way Lane which could be used for emergency access Buildings that will be constructed on the site include: a single storey Club House building, sitting to the south of the sailing lake and includes reception, office, training rooms and staff/visitors changing rooms; two buildings - the Tractor garage and the Workshop - located in proximity to the main Club House; and a single storey boat store building located on the south-western edge of the rowing lake and designed to accommodate rowing boats and the weed boat Other structures on the site will include the lake side facilities; specifically the pontoons and slipways that allow access to the lakes Four public footpaths are present within or in close proximity to the proposed development. Amendments to these are proposed to two of these as follows: Footpath DEN/23/1 will be extended along the eastern boundary of the 12

14 application site to complete the link from Knighton-Way Lane to Oxford Road, past the access road to Field Cottage. A second branch will continue around the eastern rowing lake linking with the existing footpath at IVE/6/1 (Cherry Tree Lane); and Footpath DEN/25/1, which runs along the northern boundary of the application site, will be realigned to follow the access road. 13

15 Figure 4: Illustrative masterplan 14

16 3 Construction and operation 3.1 Construction overview The site will be constructed in two broad stages. Stage 1 (2017 to 2018) will involve the construction and creation of the proposed HOAC facilities across the southern half of the site whilst Stage 2 (2018 to 2022) will involve the extension of the lake northwards and restoration of the site in the northern half of the site Sand and gravel will be extracted throughout both Stage 1 and Stage 2 in 6 sequential phases as shown in Figure 5. Access Access during construction will be from the A412 via the shared access to Summerleaze New Denham Quarry and London Concrete batching plant. Construction worksites There will be one main construction compound for both stages of construction and there will also be two satellite construction compounds during Stage Working hours will be 8am till 6pm Monday to Friday and 8am till 1pm Saturday. Outside of these hours, it is expected that the compound would have low-level lighting for security purposes. Existing working hours for the continuing Summerleaze mineral extraction are 7.00am pm Monday to Friday and 7.00am-1.00pm Saturdays Access and security will be maintained and monitored via the main office compound There will be no overnight accommodation on site during construction. 15

17 Figure 5: Graphic description of the Stages required as part of construction and operation of the proposed development Stage 1, Phase 1, 2016 (current situation as of April 2016) Stage 1, Phase 2, Q1-Q Stage 1, Phase 3, Q to Q Stage 2, Phase 4, Q2 to Q

18 Stage 2, Phase 5, Q to Q Stage 2, Phase 6, Q1 to Q Key: Stage 2, Site completion, Q1 to Q

19 3.2 Alternative locations Volume 2 Non-technical summary HS2 Ltd have been working with HOAC to identify locations suitable for them to move their facility to on a permanent basis, as their current site and lake will be impacted by the construction and operation of the HS2 proposed scheme The existing HOAC site is located in South Harefield within the Colne Valley. As such, alternative locations were considered within the Colne Valley. Despite considering 13 alternatives, no other suitable site was identified that would be able to accommodate both the land and water based activities New Denham Quarry was initially rejected as an alternative location as it was thought that timing issues would prevent HOAC being relocated before construction impacts from the HS2 Phase One ES affected their current operations. However, following discussions with Summerleaze Ltd, it was found the current excavation programme could fit within the HS2 programme Advantages of the New Denham Quarry site include: Summerleaze Ltd is in the final phases of mineral extraction. The approved restoration scheme comprises three lakes. The smaller lake and the eastern (rowing) lake are already in place; there is good access via the existing access to the quarry from the A412. There are good transport links to the M40, M25 and A4020; it could be purpose designed for HOAC use through the development of a new restoration plan; and there are low bird counts at this site. The existing lakes have been designed and are managed under an agreement with Northolt and Heathrow airports to deter birds and wild-fowl. Northolt airport have confirmed they would have no objection to a larger lake subject to a similar bird management agreement for the proposed development. 18

20 4 Preparation of the Environmental Statement The main steps in the preparation of the ES are shown in Figure 6. Figure 6: Environmental impact assessment process diagram The ES has considered the construction and operational effects on the following environmental topics, based on the requirements of the EIA Regulations: Agriculture, forestry and soils; Air quality; Community; Cultural heritage; Ecology; Land quality; Landscape and visual; Sound, noise and vibration; Traffic and transport; Waste and material resources; and 19

21 Water resources and flood risk. Volume 2 Non-technical summary The EIA process comprises the following related activities: collection of information about current environmental conditions ( the baseline ) in the vicinity of the proposed development; prediction of future environmental conditions without the proposed development ( the future baseline ); assessment of the likely beneficial and adverse significant environmental effects of the proposed development; development and assessment of proposed mitigation for identified likely significant adverse environmental effects; assessment of the remaining significant adverse environmental effects of the proposed development assuming the proposed mitigation is in place (referred to as residual effects ) Although scoped out, climate change has been taken into account within each of the technical chapters as part of the assessment. It is not anticipated that future predictions of climate change will have any effect on the proposed use of the site as a recreational area, as the proposed development does not include construction or operational uses and activities that will generate emissions at a scale that have the potential to cause significant adverse or beneficial effects for climate. 20

22 5 Environmental summary 5.1 Introduction The following section provides a summary of the assessment of likely significant beneficial and adverse residual effects of the project on an environmental topic basis. For each topic, the approach to mitigation is described A Construction Environmental Management Plan (CEMP) has been produced for the proposed development and is included in Volume 6 of this ES. 5.2 Agriculture, forestry and soils Land will be required at Ivy House Farm to construct and to operate the proposed development Due to the limited works involved, construction effects on Osborne Farm associated with the realigned footpath are likely to be negligible None of the agricultural land required by the proposed development is to be restored to an equestrian or agricultural use following construction, and as such there will be no significant temporary effects The sensitivity of the soils is greatest in relation to those on agricultural land which will be disturbed by construction activity and reinstated to another rural land-based use upon completion of the proposed development The most important consideration is the beneficial use of displaced soils within the application site. Compliance with the CEMP will ensure the magnitude of impact on soil is low The separate proposed Northern Extension to New Denham Quarry by Summerleaze Ltd would require approximately 40.5ha of agricultural land. However, no published information on the amount of BMV agricultural land within this area is available, and due to restrictions on access, no detailed soil survey has been undertaken. Assuming the worst case scenario that all of the land within the quarry extension was BMV agricultural land, the cumulative impact would be high. The permanent change of use of BMV land is assessed as a major/moderate adverse effect and is significant If the proposed Northern Extension to New Denham Quarry is permitted, this would require almost all of the remaining land that forms the Ivy House Farm holding, which is a high impact. Given that the holding has a low sensitivity to change, the proposed development would still result in a significant moderate adverse effect on the farm holding During operation, fencing of the proposed realigned public footpaths on Osborne Farm where it follows the field boundary would separate the livestock and members of the public. As such, it is unlikely that alterations to the management of the farm would be required, with a resultant negligible effect on the farm unit. 21

23 Summary of likely significant residual effects Construction of the proposed development would give rise to a moderate significant residual effect on one farm holding due to the loss of agricultural land at Ivy House Farm During construction, the cumulative residual effects with the proposed Northern Extension to New Denham Quarry on BMV land are likely to be major/moderate adverse, which is significant. Residual cumulative effects would also occur from the requirement of almost all of the remaining land which forms the Ivy House Farm holding, which will result in a moderate adverse significant residual effect No significant residual effects on agriculture, forestry and soils have been identified from the operation of the proposed development. 5.3 Air quality Taking into consideration the dust emission magnitude and the sensitivity of the area, the proposed development site has been classified as Medium Risk for potential dust soiling impacts from earthworks activities and movement of vehicles The assessment of impacts arising from predicted changes to road traffic emissions along the local road network during the worst-case construction year (2017) has concluded that the impact will be negligible for both NO 2 and PM 10 concentrations. Therefore, the effect on local air quality as a result of the construction of the proposed development will not be significant During construction, the emission of dust from construction activities will be controlled by measures within the CEMP. These include: stakeholder communication before work commences on site; monitoring; sustainable travel; re-vegetate earthworks as soon as practicable; and ensure hard surfaced road between wheel wash facility and site exit. Summary of likely significant residual effects With the implementation of the mitigation measures outlined above, no likely significant residual effects related to air quality are expected to result from any of the construction activities for the proposed development. 5.4 Community The assessment of effects on the community takes account of a range of impacts, including demolition, or partial loss, of dwellings, community facilities and public open space, road closures and diversions, amenity impacts including the effects of construction traffic, noise and visual impacts The CEMP includes measures to reduce noise, air quality, visual and construction traffic effects on local communities during construction. Proposed measures include: 22

24 appointment of community relations personnel; community helpline to handle enquires from the public; sensitive layout of construction sites to minimise nuisance as far as reasonably practicable; and specific measures in relation to air quality, noise and visual impacts will also serve to reduce impacts for the neighbouring communities, for example the construction of a noise barrier at the north east of the site to mitigate impacts on residents of Knighton-Way Lane The proposed development has been designed with the aim of minimising demolitions and loss of community facilities. As such the proposed development will not require the demolition of any dwellings or community facilities The proposed development provides amenity and recreational uses, set within a landscaped area and the routing of new public footpaths through the site means that some public access to the site is maintained. The publically accessible areas are assumed to include the area to the west of the main lake linking in (through an area between Footpath DEN/25/1 and the main lake) to the area to the north of Field Cottage between Knighton-Way Lane and the main lake. In addition the area to the north and east side of the rowing lake, through which the proposed new footpath passes between the rowing lake and the River Colne, is assumed to be publically accessible No significant adverse effects have been identified during construction or operation and therefore no mitigation measures, in addition to those set out in the CEMP, are considered necessary to mitigate impacts. Summary of likely significant residual effects There are no significant residual effects from the construction phase There will be significant beneficial residual effects resulting from the operation of the proposed HOAC facilities for the community, specifically younger people and those pursuing outdoor activities. 5.5 Cultural heritage There are four prehistoric flint scatters located within the approved quarry scheme boundaries. These deposits will be kept in situ and preserved within the proposed development. Protection measures will be put place during the construction of the proposed development and incorporated into the CEMP to avoid impacts to these significant assets Further flint scatters may be present within the proposed area for mineral extraction in the north east of the site. Archaeological evaluation will be carried out and the results will be used to determine the appropriate archaeological mitigation strategy Construction works have the potential to affect heritage assets during the construction period. Impacts will occur to assets both within the land required, temporarily or permanently, for the construction of the proposed development and 23

25 assets in the wider application site due to the visibility of plant and equipment and other construction factors Significant effects will occur as a result of physical impacts on heritage assets within the land required, temporarily or permanently, for construction of the proposed development The construction of the proposed development will remove two historic hedgerows (assets of moderate value (HOAC135 and HOAC137), causing major adverse effect The construction of the proposed development will remove the setting of a historic hedgerow, by removing the associated hedgerows, which form the surviving part of the early post-medieval landscape. The hedgerow itself will not be physically impacted The potential early prehistoric artefacts, and the later medieval/post-medieval features recorded by the geophysical survey located in the north eastern area of the proposed development, will be removed by the construction of the proposed development. This will cause a high impact and a major adverse effect There may be some potential for late prehistoric to post-medieval remains located on the brick earth deposits in the north western area of the proposed development, which will be removed by the construction of the proposed development. This will cause a high impact and a moderate adverse effect There will be no physical impacts on buried archaeological remains or other heritage assets arising from the operation of the proposed development Following the implementation of the mitigation strategies which are set out in the CEMP, it is considered that there will be no significant temporary effects from the construction of the proposed development. Summary of likely significant residual effects Archaeological remains that may be present within the application site area which have not previously been removed by the existing quarry will be permanently removed during construction of the proposed development. This will result in a permanent adverse significant residual effect A programme of archaeological works will be prepared to investigate, analyse, report and archive these assets Two historic hedgerows will be permanently removed and the setting of a third hedgerow will be permanently altered. This will result in a permanent adverse significant residual effect. 5.6 Ecology The potential presence of a bat maternity roost in the small number of trees to be removed for construction cannot be ruled out. Without mitigation, these impacts could result in a permanent adverse effect on the species that make up the bat assemblage. On a precautionary basis, it is assumed that there would be a permanent adverse effect on the conservation status of the species that make up the bat assemblage that is significant at up to the county/metropolitan level. 24

26 5.6.2 Construction of the proposed development will result in the loss of rough grassland habitat that may reduce foraging and sheltering opportunities required to maintain viable populations of reptiles assumed to be present at the site. Without mitigation, these impacts could result in a permanent adverse effect on the conservation status of the species that make up the reptile assemblage that is significant at up to the district/borough level On a precautionary basis, the exposed sand and gravel habitat within the quarry is assumed to be used by a single pair of little ringed plover which will be lost due to construction of the proposed development. The conservation status of little ringed plover is dependent on areas of exposed sand and gravel to provide suitable nesting habitat. The loss of a breeding pair would result in a permanent adverse effect on the conservation status of little ringed plover that is significant at the district/borough level The proposed development will include the creation of a mosaic of habitats, which when combined with the areas of retained habitat and areas previously enhanced as part of the restoration scheme will provide the following habitat areas: broadleaved woodland; wet woodland; willow woodland (biomass production); standing water (lake); stream habitat (buffer strip); tall emergent vegetation (including reedbed); tussocky grassland; wildflower grassland; and hedgerow In comparison with the approved Summerleaze Ltd restoration scheme (including Phase 4C, CM/32/14) the proposed development will provide a similar habitat composition although the extent of the habitats provided are different in some cases. In terms of those habitats with potential to establish as habitats of principal importance, in total approximately 10.5ha of additional habitat will be provided by the proposed development in addition to 497m of extra hedgerow resulting in a net gain in biodiversity overall in comparison with the approved restoration scheme Compensatory habitat to address impacts on populations potentially present as part of the assumed bat assemblage at the site will be provided through the creation of broadleaved woodland and wet woodland, as well as hedgerows. Once established, these habitats would provide roosting and foraging opportunities for the bats. Along with the abundance of alternative roosting and foraging opportunities in the surrounding woodland areas, it is considered that the provision of these habitats would be sufficient to maintain the favourable conservation status of the populations within the assemblage and reduce the effects to a level that is not significant. 25

27 5.6.7 Compensatory habitat to address the impacts on possible populations within the assumed reptile assemblage at the site will be created through the provision of tussocky grassland. The large expanses of open water, hedgerow and woodland edges will also provide habitat features for foraging, breeding and hibernating sufficient to maintain the conservation status of the populations affected reduce the effects to a level that is not significant No significant effects are expected for barn owl, the breeding bird assemblage or the terrestrial invertebrate assemblage assumed to be present at the site. However, the creation of hedgerows, woodland and grassland habitats as described above will provide additional nesting and foraging habitat for barn owl and breeding birds, and also encourage the establishment of new invertebrate populations. Summary of likely significant residual effects With the implementation of mitigation, compensation and enhancement measures described above, the effects are reduced to a level that is not significant, except for the loss of little ringed plover habitat resulting in a permanent adverse significant residual effect on the population During construction, exposed sand and gravel habitat within the quarry will be lost which is assumed to be used by a single pair of little ringed plover. Certain mitigation measures for this species, such as sand and gravel islands, could not be implemented because it could encourage nesting wildfowl and gulls and would therefore not be in agreement with the long-term Bird Management Agreement dated August 2013 that is in operation at the site. However, little ringed plovers breed on areas of newly worked sand and gravel, and as such are adapted to move to new areas of habitat as they become available There will be no likely significant residual ecological effects during operation of the proposed development. 5.7 Land quality The proposed development will require a small additional area for quarrying which is outside of the existing quarry. However, the temporary effect on the resource will be the same as if the original mineral planning extraction had been delivered and therefore the effect may be considered negligible Construction of the proposed development includes the removal of the majority of the sand and gravel mineral in the application site, for beneficial use. On this basis, the permanent effect of the works is to deliver all the mineral within the Summerleaze Ltd approved restoration scheme. The effect of removal under the proposed development is only slightly greater than that delivered in the original mineral extraction planning permission, and therefore the effect may be considered negligible It is considered unlikely that the operation of the outdoor activities centre will give rise to any significant contamination. It is likely that only small volumes of chemicals will be held on the proposed development when operational No significant cumulative effects are anticipated as a result of the operation of the proposed development. 26

28 5.7.5 Whilst the extent of extraction for the proposed development results in a broadly similar level of mineral extraction compared to the previous Summerleaze Ltd permissions, it is recognised that the proposed northern quarry extension has the potential, if granted, to extend the duration of mineral extraction in the area. However, this is not expected to have a significant effect at a regional level. Summary of likely significant residual effects Mitigation of the effects on mineral resources is minimal as the effect is negligible. This will be achieved by following the extraction plan which broadly mirrors that set out in existing planning permissions for the site The CEMP details the approach to managing potential land contamination matters. No additional mitigation measures are considered necessary to mitigate risks from land contamination at the construction stage beyond those set out in the CEMP, those defined in the Environmental Permit and those instigated as part of required remediation strategies Maintenance and operation of the proposed development will be in accordance with environmental legislation and good practice whereby appropriate spillage and pollution response procedures will be established If remediation works are required during construction, there will be on-going monitoring requirements, as appropriate, following their completion. Such monitoring, including monitoring of groundwater quality or ground gas, could extend into the operational stage of the proposed development There are no likely significant adverse residual effects are anticipated during construction or operation of the proposed development. 5.8 Landscape and visual assessment During construction, the extension of the existing sand and gravel extraction area to the agricultural land north of Field Cottage and west of Knighton-Way Lane will be clearly visible over intervening fields and will result in a noticeable change to a key feature of the view. This will result in a moderate adverse significant effect during the period on the view south-west along public footpath DEN 25/1 and the view south-west from Knighton-Way Lane During Stage 2: of operation, there will be a moderate adverse significant effect on the view south-west along public footpath DEN 25/1 and the view southwest from Knighton-Way Lane During the operational period from , with the removal of the mitigation earthworks bund in place for the duration of construction, there will be a moderate beneficial significant effect the view south-west along public footpath DEN 25/1 and the view south-west from Knighton-Way Lane Post HOAC 2022, there will be moderate beneficial effects on the following landscape character areas and views: moderate beneficial significant effect in years 1, 15 and 60 of operation on the Colne Valley Floodplain LCA; 27

29 moderate beneficial significant effect in years 15 and 60 of operation on view south-east across New Denham Quarry from public footpath DEN/25/1; moderate beneficial significant effect in years 1, 15 and 60 of operation on view south-west along public footpath DEN 25/1 and view south-west from Knighton-Way Lane; and moderate beneficial significant effect in years 1, 15 and 60 of operation views south-east/west and north-east/west from Field Cottage. Summary of likely residual significant effects The CEMP includes measures to avoid or reduce landscape and visual effects during construction. These include: existing trees and vegetation will be retained where possible; use of well-maintained site hoardings and fencing; designing lighting to avoid unnecessary intrusion onto adjacent buildings and other land uses; use of temporary bunding 3m high to screen views of the construction works from residential properties in New Denham; and maintenance of planting and seeding works and implementation of management measures as landscape works are completed during the construction period During construction of the proposed development, there will be significant residual effects on views at two locations near Knighton-Way Lane due to the proximity of the proposed development During operation, the presence of the proposed development will result in significant beneficial residual effects on local character and nearby views. 5.9 Sound, noise and vibration Significant construction noise or vibration effects on any receptors are unlikely to occur from works associated with construction of the proposed development Due to the nature of the outdoor activities proposed as part of the operation of the proposed development, operational noise and vibration is not expected to lead to significant effects. Summary of likely significant residual effects The assessment of construction noise includes the implementation of the principles and management processes, as set out in the CEMP: Best Practicable Means (BPM) will be applied during construction to minimise noise (including vibration) as far as reasonably practicable at neighbouring residential properties; as part of BPM, the following mitigation measures are applied: 28

30 - noise and vibration control at source; and - screening. lead contractors will seek to obtain prior consent from the relevant local authority for the proposed construction works to minimise construction noise, including control of working hours, as far as reasonably practicable; and contractors will undertake and report such monitoring. Monitoring data will be made available to the local authorities A 5m high noise barrier is proposed at the north eastern end of the site to screen residents on Knighton-Way Lane from noise from phase 5B of mineral extraction operations in the north east of the site. The mitigation measures reduce sound levels from mineral extraction and earth moving operations during Stage 2 below the guideline noise limits at noise sensitive receptors; hence a significant adverse noise effect from these activities is unlikely to occur The avoidance and mitigation measures reduce noise inside all dwellings from the Stage 2 construction activities such that it is does not reach a level where it would significantly affect residents The measures also reduce the adverse effects of outdoor construction noise on the acoustic character around the local residential communities such that the effects are not considered to be significant There will no significant adverse residual effects during construction or operation of the proposed development Traffic and transport Construction of the proposed development is forecast to result in changes in daily traffic flows due to construction vehicles accessing the site Estimated delays at the A412 New Denham Quarry roundabout are not sufficient to result in any significant adverse effects during construction Stage 1 construction of the proposed development will not result in increases in daily traffic flow of more than 30% on the A412 for all road vehicles but will for HGVs resulting in a moderate adverse effect in traffic related severance for non-motorised users. However, the A412 does not include footways and pedestrian crossings and consequently non-motorised users are unlikely to be affected by any increase in traffic. Summary of likely residual significant effects The following measures have been included as part of the design of the proposed development that will avoid or reduce impacts on transport users: all roads within the vicinity of the proposed development will be kept open during construction resulting in no diversions of traffic onto alternative routes; HGV routeing, as far as reasonably practicable, will be along the strategic road network and using designated routes; and 29

31 Volume 6: the CEMP includes measures which seek to reduce the impacts and effects of deliveries of construction materials and equipment, including reducing lorry trips during peak background traffic periods A number of improvements to public footpath in the area are proposed that would be beneficial but these have not been assessed as significant beneficial effects Waste and material resources The main objective is to limit the generation of waste, and to reuse, recycle and recover waste generated by the proposed development As set out in the CEMP, the contractor will undertake the appropriate environmental control measures for environmental good practice during the construction works It is considered that the majority of the excavated and construction waste will be inert and can be appropriately reused on site, where possible, sent for beneficial reuse or recycled locally. Following the creation and implementation of the draft SWMP as well as implementation of the principles of the waste hierarchy and measures to reuse/recycle the waste, it is anticipated that the waste will be managed to appropriate standards The residual effects that remain post-mitigation on landfill, particularly in respect of surplus excavated material, are expected to be minor adverse (as a reasonable worst case scenario). Summary of likely significant residual effects Overall, it is considered that the majority of the excavated and construction waste will be inert and will be sent off-site for disposal. The residual effects that remain postmitigation on landfill, particularly in respect of surplus excavated material, are expected to be minor adverse (as a reasonable worst case scenario) With respect to the proposed Northern Extension to New Denham Quarry, it is important to identify that if the extension is granted permission any excavated waste produced during Stage 2 will remain on the site for use by Summerleaze Ltd in the restoration of the extension. This will partially mitigate for the minor adverse effect identified for the proposed development from disposing material off-site and result in a reduced adverse effect There are no likely significant residual effects as a result of the construction or operation of the proposed development Water resources and flood risk There is currently no significant risk of flooding to the site from surface water, reservoirs, sewers or other nearby waterways such as the Grand Union Canal, which is located on the other side of the River Colne from the proposed development No significant effects on surface water, groundwater or flood risk have been identified due to the mitigation measures proposed. Such mitigation measures include the use of approved working methods, controls on imported fill material and the application of best practice and the CEMP. 30

32 The CEMP sets out the measures and standards of work that will be applied to the construction of the proposed development. These measures and standards of work will provide effective management and control of the impacts during the construction period Generic examples of measures to be applied during operation and management of the proposed development will be described in the draft operation and maintenance plan for water resources and flood risk. The measures will be used to mitigate any impacts on the quality and flow of surface watercourses and groundwater bodies, in order that there are no significant adverse effects on the water environment The proposed development will result in the creation of a large raised reservoir. However, the design of the reservoir, in accordance with the requirements of the Reservoirs Act 1975, mitigates this risk and means that the likelihood of flooding is extremely remote (the requirements of the Reservoirs Act 1975 far exceed the normal planning standards). Summary of likely significant residual effects South of the site, properties on Cherry Tree Lane as well as Watergate Farm (both more vulnerable development) will experience a reduction in predicted flood water levels and therefore a significant beneficial effect. 31