Project Number: ENVIMSW002194
AVONMOUTH SEVERNSIDE ENTERPRISE AREA (ASEA) ECOLOGY MITIGATION AND FLOOD DEFENCE SCHEME
Stockpile at land off A403 at Northwick –
ES Addendum
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 1
Project Number: ENVIMSW002194
Issue and Revision Record
Revision Date Originator Checker Approver Description 01 07/11/19 C Postlethwaite S. Booley, J. M Secker For client & E Haggett Faber & M Reid approval 02 04/12/19 C Postlethwaite S. Booley, J. M Secker For issue & E Haggett Faber & M Reid
Document reference: ENVIMSW002194-BMM-XX-A10-RP-EN-0301019
EA file naming and file metadata
BS1192 file name Stockpile at Northwick Landfill – ES Addendum BS1192 suitability S8 – Shared for client review, comment and/or acceptance Revision P02 EA deliverable reference C0010_19 EA work stage EA4 Level of Development LOD4 Title Stockpile at Northwick Landfill – ES Addendum
Information class: Standard
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Forecasts presented i n this document were pr epared usi ng Data and the report is dependent or based on D ata. Inevitabl y, some of the assumptions used to develop the for ecasts will not be realised and unantici pated events and circumstances may occur. C onsequentl y M ott MacDonal d does not guarantee or warr ant the concl usi ons contained i n the repor t as there are li kel y to be differ ences between the for ecasts and the actual results and those di ffer ences may be material. Whil e we consi der that the infor mation and opini ons gi ven i n this r eport are sound all parti es must rel y on their own skill and j udgement when making use of it.
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Introduction 5
Scheme description 9
Legislation and policy context 17
Consultation 20
Population and human health 22
Biodiversity 25
Landscape character and visual amenity 30
Water Environment, Flood Risk and Water Framework Directive 33
Archaeology and cultural heritage 38
Geology and Soils 40
Land Use 43
Air quality 45
Climate change 47
Major accidents and disasters 49
Noise and Vibration 52
Cumulative effects 61
Conclusion 64
Glossary 70
Appendices 74
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Tables Table 1-1: Significance matrix 7 Table 4-1 : Consultation carried out for the ASEA scheme 20 Table 4-2 : Consultation carried out for the proposed stockpiling 21 Table 6-1: Statutory designated sites 26 Table 6-2: Non-statutory designated sites 26 Table 10-1: Conceptual ground model for the proposed development area 40 Table 10-2: Mitigation Measures 41 Table 15-1: Example threshold of potential significant effect at dwellings 54 Table 15-2: Examples of time periods, averaging times and noise levels associated with the determination of eligibility of noise insulation 54 Table 15-3: Summary of plant for construction works 56 Table 15-4: Stockpiling noise predictions 56 Table 15-5: Internal Haul Road Noise Predictions 57 Table 16-1: Potential cumulative effects between the proposed stockpiling and the ASEA scheme 62 Table 17-1: Population and health aspects, effects and mitigation measures 64
Figures Figure 2-1: The ASEA Scheme 11 Figure 2-2 : Figure The Proposed Stockpile 14 Figure 2-3 : Alternative Stockpile Location Considered 15
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Introduction
1.1 Purpose of this report This document is the Environmental Statement (ES) addendum for the planning application for stockpiling (‘the proposed stockpile’) of embankment fill material (soil), associated with the construction of the Avonmouth and Severnside Enterprise Area (ASEA) Flood Defence and Ecology Mitigation Project (‘the ASEA scheme’). The ASEA scheme is being promoted by a partnership of Bristol City Council (BCC) and South Gloucestershire Council (SGC) and the Environment Agency. The purpose of this report is to provide an addendum to the ES produced in 2018 (‘the ASEA ES’), to assess the proposed changes to the stockpiling arrangements for the construction of the ASEA scheme, namely the new location for the proposed stockpile, and to present the findings of the assessment undertaken as part of the Environmental Impact Assessment (EIA) process. The EIA is being completed under the Town and Country Planning (EIA) Regulations 2017 (SI 2017/ 571) (‘the EIA Regulations’).
1.2 Scope of the ES addendum The baseline for this ES addendum is the assessment carried out within the ASEA ES. The ASEA ES assessed a stockpile within Area 5 of the ASEA scheme, as shown in Figure 2-1 below. As described in Section 2, the proposed stockpile location has now moved due to concerns around potential impacts to historic ridge and furrow field patterns within Area 5, and this ES addendum therefore assesses the new location for the proposed stockpile, including the difference between the two proposed locations. No other elements of the ASEA scheme have changed, and therefore this ES addendum only relates to the new changed location of the proposed stockpile. Therefore the ASEA scoping report prepared by CH2M (Jacobs) in July 2017 was deemed to remain valid prior to the production of this ES addendum. Topics considered within the ASEA ES have been deemed applicable to this ES addendum and have been incorporated. in order to comply with the EIA Regulations additional topics have been included, furthermore noise and vibration has been scoped in. Due to necessary considerations surrounding potential dust creation associated with stockpiling material, air quality has been scoped in as an additional topic within this ES addendum. The following topics are considered within this report:
• Population and human health; • Biodiversity; • Landscape character and visual amenity; • Water and water framework directive (WFD);
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• Archaeology and cultural heritage; • Geology and soils; • Land use; • Air quality; • Climate change; • Major accidents and disasters; and • Noise & vibration.
1.3 Approach to the ES addendum This ES has been produced as a requirement of the Town and Country EIA Regulations (2017) and the purpose is to report on environmental impacts arising from projects that are potentially likely to be deemed significant (further detailed in Section 3). As this ES addendum has been produced in line with the ASEA ES, it has been undertaken with reference to the following documents:
• Town and Country Planning (EIA) Regulations 2017 (SI 2017/571); • Guidelines for Environmental Impact Assessment, Institute of Environmental Management and Assessment (IEMA), 2004; and • EIA planning practice guidance, DCLG, 2014.
Assessment of significance There is no statutory definition outlining what constitutes a significant effect. This is due to the fact that the interpretation of a significant effect is dependent on the qualified specialist’s opinion who is assessing the effect. As outlined in the ASEA ES the prediction of significance is a three stage process: 1. Identification of the baseline conditions and the value or sensitivity and importance of receptors; 2. Identification of the magnitude (i.e. size) of change (impact) upon each receptor; and 3. Identification of the significance (i.e. importance) of the effect, which is the product of a combination of the above two variables. To determine the value or sensitivity of a receptor:
• Very high – International importance; • High – National importance; • Medium – Regional/county importance; and • Low – District/parish importance.
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To determine the magnitude of an impact on a receptor:
• Major adverse – impact with serious consequences and/or on a large area; • Moderate adverse – impact with undesirable consequences; • Minor adverse – discernible negative impacts and/or on a small area; • Negligible – no impact or no discernible impact; • Minor beneficial – discernable positive impacts and/or on a small area; • Moderate beneficial – impact with favourable consequences; and • Major beneficial – impact provides substantial gains and/or on a large area. Beneficial and adverse; temporary and permanent; direct, indirect and secondary; and cumulative effects are all taken into consideration within this ES addendum. In terms of assessing the significance of an effect, Table 1-1 below has been used.
Table 1-1: Significance matrix Value / sensitivity Very high High Moderate Low Magnitude Major adverse Major adverse Moderate Moderate Minor adverse adverse / adverse / moderate major adverse adverse Moderate Moderate Moderate Minor adverse Minor adverse adverse adverse / major adverse / moderate adverse adverse Minor adverse Minor adverse / Minor Minor adverse Minor adverse moderate adverse / adverse moderate adverse Negligible Negligible Minor Minor beneficial Minor Minor Minor beneficial / major beneficial / beneficial beneficial beneficial moderate beneficial Moderate Moderate Moderate Minor Minor beneficial beneficial / beneficial beneficial / beneficial major beneficial moderate beneficial Major Major beneficial Moderate Moderate Minor beneficial beneficial / beneficial beneficial / major moderate beneficial beneficial Source: ASEA ES, (CH2M (Jacobs), 2017). A significant effect under the meaning of the EIA Regulations is assessed to be moderate or above.
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Assumptions and limitations Assumptions and limitations have been made for this ES addendum and are noted below.
Biodiversity An Ecological Impact Assessment (EcIA) has been produced to inform this ES addendum, for which site walkovers and ecological surveys were undertaken. It should be noted that flora and fauna are often transient in nature and survey visits can only provide a general indication of species present.
Landscape Character and Visual Amenity The landscape assessment of the site was undertaken in late summer when the trees and other vegetation was in leaf. Professional judgement was used by BMM JV landscape specialists to assess the likely visibility of the stockpile in winter months.
1.4 Quality assurance and competent experts The Environment Agency and Mott MacDonald are members of IEMA and hold its EIA Quality Mark. The Quality Mark Scheme allows organisations that lead the co-ordination of statutory EIAs in the UK to make a commitment to excellence in their EIA activities and have this commitment independently reviewed. The EIA Quality Mark is a voluntary scheme, with organisations free to choose whether they are ready to operate to its seven EIA Commitments. Mott MacDonald is a multidisciplinary consultancy with over 20 years’ experience of undertaking complex and challenging environmental impact assessments (EIA) and of writing environmental impact assessment reports for a wide range of projects. These include some of the world’s largest infrastructure, engineering and development projects. Mott MacDonald maintains high professional standards amongst staff both individually and across technical areas of Practice. Individually, technical staff are subject to annual performance reviews which evaluate their Continued Professional Development. Staff are also encouraged to be affiliated with external professional bodies such as IEMA, relevant to their area of practice and progression in the business is contingent on attaining professional standards (such as chartership) or the ability to demonstrate equivalent levels of competence. As a business technical “Practices” are maintained, which are internal professional networks that span organisational and geographical boundaries. These help to maintain high professional standards across technical disciples as well as facilitating a contribution to the wider development of the Environmental Consulting industry. Mott MacDonald’s Environment Practice currently includes the following specialist areas:
• Acoustics, noise and vibration; • Agriculture, soils and forestry; • Air quality;
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• Ecology and biodiversity; • Ecosystem services; • Environmental and social due diligence; • Environmental assessment; • Environmental policy and regulation; • Heritage and archaeology; • Land contamination and remediation; • Landscape and urban design; • Natural resources assessment; • Permitting, licensing and compliance; • Sustainability strategy and assessment; • Urban and town planning; and • Water quality. Note that there are a range of other practice groups relevant to EIA (including Carbon Management, Coastal Management, Climate Resilience, Economics, Flood Risk, GIS, Health, Social, Transport Planning and Waste) from which experts can be drawn on. Where expertise is not available internally, external consultants may be used to bridge that gap. Scheme description
2.1 The ASEA scheme The ASEA area is designated as an Enterprise Area to recognise its internationally significant industrial location and a strategically important employment area in the West of England. The ASEA lies to the northwest of Bristol, is 1,800ha in size, extends for 8km on low lying land adjacent to the Severn Estuary and lies immediately adjacent to the M5 and M49 motorways. It contains two main areas of economic activity; Avonmouth in the south and Severnside in the north. The strategy for the ASEA is for further industrial and commercial development to ensure that the area expands its role as an internationally significant industrial location, able to attract business investment and provide increased employment for the local and wider population. The ASEA scheme, as shown below in Figure 2-1, is designed to provide flood defences for the ASEA (and other areas) which will enable continued economic growth in Bristol and South Gloucestershire. As well as providing flood defences, the ASEA scheme includes the creation of two areas of ecological mitigation in the form of wet grassland and ponds, required to mitigate for the loss and degradation of habitats (coastal floodplain) due to
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Project Number: ENVIMSW002194 previous and forthcoming development in the ASEA area, including warehouse development. The creation of lowland wet grassland (including a network of freshwater ditches and scrapes) and open water habitats (freshwater lakes and ponds) is required to mitigate for adverse effects to the integrity of the Severn Estuary SPA supporting habitat . A Habitats Regulations Assessment1 (HRA) has confirmed the need for these wetland habitat areas to mitigate for all the areas that either have planning consent under the extant 57/58 Consent2 or are expected to form part of further planning applications in the ASEA area. To comply with the Habitats Regulations Assessment (HRA) requirements, the ecological mitigation must include a minimum of 73.5 hectares of wet grassland habitat and 6.5 hectares of open water, which should encourage bird species of national, regional and local significance including those of European interest such as gadwall, teal, mallard, shoveler, pochard, tufted duck, lapwing, curlew and common snipe. In addition to the habitat creation, the ASEA scheme will enlarge and strengthen the existing flood defence barriers currently situated along the Severn Estuary and Avonmouth flood defence zones. Proposed works include the enlargement of existing flood defence earth bunds that exist from Aust in the northern sector of the scheme (Area 1) to below the M5 bridge at Avonmouth in close proximity to Lamplighters Marsh Local Nature Reserve (LNR). Areas 1, 2, 3A and 3B form the tidal defences and associated environmental improvement works and include the following:
• Provision of flood defence walls at Old Passage, protecting properties which are located in front of raised land at the Northern section of Area 1. • Raising of existing flood bank defences from Old Passage to Northwick along Severnside coastline to New Passage. • Raising of existing coastal sea wall defences between New Passage and Severn Beach. • Extension of flood defences between Severn Beach and Avonmouth Docks, directly protecting the ASEA. However, it will not completely protect the existing Avonmouth to Severn Beach branch line in this location, due to land use and conservation constraints. • Flood walls and ground raising at the northern end of Avonmouth Docks. • Further flood defences are proposed from Avonmouth Dock lock gates to high ground upstream of the Avonmouth M5 Bridge.
1 Cresswell Associates/South Gloucestershire Council/Bristol City Council/Natural England (2011). Severnside & Avonmouth Wetland Habitat Project 2011 – Stage 2: Review of Consent at Severnside and Avonmouth Impact Assessment (‘the Cresswell Report’). 2 A historic 1957/58 consent governing Severnside was deemed legally extant by the High Court in the early 2000s and is currently under development. The area of the 57/58 permission is currently being developed out in a series of phases.
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• Modification of a number of outfalls for major watercourses within the Enterprise area. This will bring the structures to a suitable defence standard while also repairing existing structural degradation and improving long term maintenance access. Area 4, Hallen Marsh, will be used to create freshwater wet grassland habitat, with ephemeral bodies of water, such as shallow scrapes that dry-up in summer which can be reconciled with continued agricultural practices such as livestock grazing or management for hay or silage. While this habitat creation will be used as mitigation for the industrial and commercial development within the ASEA, the impacts on farming, landscape and other species will need to be addressed. Areas of permanent standing water in the form of ponds and lakes will be created with the Area 4 boundary. Area 5, Northwick, will be used to create areas of permanent standing water in the form of ponds and lakes along with scrapes. Due to the low-lying nature of some of the land, t large expanses of wet grassland habitat, with some ephemeral bodies of water (such as shallow scrapes that dry-up in summer) will be created.
Figure 2-1: The ASEA Scheme
Source: Ordnance Survey (Licence Number: 100026791)
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2.2 The proposed stockpile In order to construct the earth embankments in Area 1, suitable material (soil) will be imported from an off-site location and stored in a stockpile, before being transported to the working area for incorporation within the earth embankments along Area 1. Soil classed as ‘2C Stoney Cohesive’, in accordance with the Design Manual for Roads and Bridges (DMRB)3 will be utilised throughout the ASEA scheme, wherever there is a need for material to construct an earthwork embankment. This will predominantly be in Areas 1, 3A and 3B. Approximately 150,000m3 of soil will be imported to the proposed stockpile, of which approximately 80,000m3 will come from external sources and the remaining 70,000m3 will be surplus from Area 4. Approximately 30,000m3 of the 80,000m3 from external sources will come from a local quarry, where the material is surplus to requirements. The source of the remaining 50,000m3 from external sources is to be determined, but it will be imported using 8-wheel lorries (approx. 32 tonnes gross weight). The soil will be moved between the stockpile and the construction site using a combination of 8-wheel road lorries and 25/30 tonne articulated dump trucks, dependent on where it is needed. As a worst-case estimate, there would be up to 100 lorry movements per day importing soil, refer to the Transport Assessment (ENVIMSW002194-BMM-XX-A10-RP-EN-0301018) for further details of traffic movements. A haul road will be constructed within the stockpile area, to enable movement within the site. As lorries will access the proposed stockpile directly from the A403, measures will be taken to ensure mud is not trafficked onto the road as this could pose a skid hazard to traffic on the A403. These measures could include road sweepers, rumble strips and wheel washing facilities. The haul road will be a mixture of hard core and tarmac, which will be removed once the stockpiling is completed so the fields can be restored to their existing condition. The soil will be stored to a maximum of 2m in height, although this may be lower due to conditions on site when the stockpile is imported. It is intended that the stockpile levels will be kept below the level of the hedgerows round the former landfill site to minimise the potential for visual effects. The stockpile will also be constructed to provide acoustic screening to nearby properties, with soil deposited in the eastern sections first. As the stockpile will be in place for an extended period of time it will be seeded to prevent windblown dust and sediment within surface water run-off. The stockpile will be located on a former landfill, as shown below in Figure 2-2 : The Proposed Stockpile. The landfill licence was issued in 1983 and by 1999 the site had been returned to agricultural use. The landfill formerly accepted controlled wastes, including industrial effluent treatment sludges, animal hides, sewage screenings, plastics, rubber, polythene, contaminated excavation waste, household waste, food and food processing waste, asbestos, tar, bitumen, pitch, asphalts, waste treated timber, water based dyestuffs
3 Manual of Contract Documents for Highway Works, Volume 1 Specification for Highway Works, Series 600 Earthworks, Available online at http://www.standardsforhighways.co.uk/ha/standards/mchw/vol1/index.htm, accessed August 2019.
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Project Number: ENVIMSW002194 and printing industry wastes.4 The landfill is capped and the proposed stockpiling will be carried out in such a manner as to avoid damaging the cap, by placing a geotextile membrane on the soil surface before the stockpile soil is deposited. Prior to this geotextile membrane being installed, the topsoil layers will be removed and stored. Following the use of the stockpile, the geotextile membrane will be removed and the topsoil will be reinstated and reseeded to return the site to its pre-construction conditions. The location chosen for the stockpile currently consists of grazed fields with a historic use as a landfill, located adjacent to the Severn Estuary Special Area of Conservation (SAC), SPA and Ramsar site, and Site of Special Scientific Interest (SSSI), but it is not located within these designated sites . In addition, it is also located more than 200m from the ‘Northwick Warth and Flash’ and the ‘Cake Pill, Aust Warth’ high-tide roost sites and contains suboptimal habitat for overwintering birds (see Section 6.5). To the east of the stockpile location there is a residential property “The Old Piggery”, which is separated from the fields proposed to contain the stockpile by the A403 road (see Appendix A: Environmental Constraints Plan) Further south of the proposed stockpile location there are more residential and agricultural properties. While the redline boundary and planning application cover all three fields of the former landfill, it is intended that the soil storage be limited to the southern two fields, with a portion of the middle field left vacant to enable access to the northernmost field. However, should adverse effects be identified from the stockpiling, as discussed further in Sections 8.5, 8.6 and 10.5, then the third field could also be used for mitigation. This would be agreed with the landowner prior to the works being extended to the third field.
4 Symonds (2000), ICI plc, Northwick Warth Site, Severnside, Bristol, Phase I Environmental Risk Assessment and Exploratory Site Investigation Report.
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Figure 2-2 : The Proposed Stockpile
Source: Ordnance Survey (Licence Number: 100026791)
2.3 Study area and boundaries The study area for this ES addendum is limited to the area shown in Figure 2-2 above. Topic specific areas of assessment are listed in Chapters 5 to 16 below. The site location along with nearby environmental constraints can be seen in Appendix A: Environmental Constraints Plan.
2.4 Timing of works The soil will be stored for a minimum of 18 months until the completion of the ASEA scheme’s construction. Stockpiling will begin from March 2020 (or whenever planning permission is granted). It is anticipated that soil will start to be exported from the stockpile in March 2021.
2.5 Alternatives considered This ES addendum and the planning application that it supports, have been produced as the originally proposed stockpile location within Area 5 has been ruled out due to the presence of historic ‘ridge and furrow’ field patterns. Ridge and furrow is a form of Medieval and later cultivation that produced a ‘corrugated’ pattern of earthworks within field systems. The origins of ridge and furrow cultivation can be traced to the 10th century AD, and was widespread by the 13th century AD.
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A desk-based assessment carried out for the planning application for the ASEA scheme5 noted that ridge and furrow cultivation is evident across the site, but the majority is located in the western and central areas of the site; particularly in the south-west and north-west. It was determined, in conjunction with the South Gloucestershire County Archaeologist that there is an area of ridge and furrow to the north of Area 5, adjacent to the A403 (shown in Figure 2-3 that was considered to be less valuable. This area was therefore investigated for the potential to accommodate a stockpile, as it lies within the consented red line boundary for the ASEA scheme.
Figure 2-3 : Alternative Stockpile Location Considered
Source: Ordnance Survey (Licence Number: 100026791)
However, this alternative area was ruled out due to the following reasons.
• Great crested newts (GCN) - the majority of the area is within 250m of pond 5.33, which has a confirmed GCN population. Works should not be carried out within 250m of a confirmed GCN population. Work would also need to remain 20m from any hedgerow, as the connectivity of habitat between pond 5.33 and other fields increases the likelihood of GCN being present outside of the 250m exclusion zone. In order to exclude newts from the area, the fields would need to be prepared first to make them unsuitable for amphibians and reptiles. This will be done through the maintenance of a 5m section of grass around the stockpile periphery, which will kept at a maximum of 5cm in height to deter amphibians and reptiles from entering the area. If GCN are discovered on site, then works will stop and an EPS (European Protected Species) licence will need to be applied for. The option to install GCN fencing should also be reconsidered. Therefore, there remains a risk of delays to
5 CgMs Heritage (2018), Archaeological Desk-Based Assessment, Avonmouth Habitat Creation Scheme: Area 5 Avonmouth
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stockpile in the event that GCN were found in the area. This would significantly delay the earthworks programme and the ASEA scheme as a whole. • Ridge and furrow protection - in order to protect the fields from damage, bog matting would be required. To utilise this over the entire 6.8 hectares would cost approximately £3.4 million (assumes approximately 13,600 bog mats at £250 each). An additional 400 bog mats (approximately £100k), would also be required for the 400m southern access route, which would also run through areas of ridge and furrow. • Site Access – Lorry movements to and from the stockpile area along the southern access route through the ridge and furrow could number up to 20,000 lorry movements, with 640,000 tonnes of loading passing along a single route across the construction duration. This could damage this ridge and furrow system, even with bog mats in place. Alternative access could potentially be gained, subject to agreement with landowners, from the access north of the site off the A403, but this access would not be suitable for the outward haul as this would mean loading soil back into road lorries instead of articulated dump trucks, increasing programme and cost. Stockpiling in this alternative proposed zone is therefore considered to be impractical and too costly, and also presents both a significant environmental and programme risk due to the presence of GCN.
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Legislation and policy context
3.1 The EIA Regulations The Town and Country Planning (Environmental Impact Assessment) Regulations 2017 (SI 2017/ 571) (referred to as ‘the EIA Regulations’) identify types of development where consideration of the need for EIA is required. Schedule 1 developments always require an EIA, but Schedule 2 developments only require an EIA if the project is likely to give rise to significant environmental effects by virtue of the size, nature and location of the proposal (as detailed in Schedule 3 of the EIA Regulations). The ASEA scheme falls under Schedule 2 of the EIA Regulations and a screening opinion was therefore sought from BCC and SGC in March 2017, which confirmed that an EIA was required. As the proposed stockpile is an associated development with the ASEA scheme, an EIA is also required. However, as the proposed stockpiling represents a small change to the ASEA scheme that was already assessed in the ASEA ES6, it is considered that an addendum to the ASEA ES is sufficient to meet the requirements of the EIA Regulations. This ES addendum will be submitted for consideration and approval along with an application for planning permission under the Town and Country Planning Act 1990 (as amended). This will be sought from SGC.
3.2 International legislation
Habitats Directive and Birds Directive EU Directive 92/43/EEC on the Conservation of Habitats and Wild Flora and Fauna (known as the ‘Habitats Directive’) protects habitats and species of European nature conservation importance. Together with Directive 2009/147/EC on the Conservation of Wild Birds (the ‘Birds Directive’), the Habitats Directive establishes a network of nationally important sites designated for their ecological status. These include SACs and SPAs. Internationally important wetlands designated under the 1971 Ramsar Convention are also afforded the same protection as SPAs and SACs. The Conservation of Habitats and Species Regulations 2017 (as amended) transpose the Habitats and Birds Directives in to UK law and place a duty on operating authorities to maintain the integrity of sites designated for nature conservation importance. An HRA screening has been carried out to accompany this ES addendum (ENVIMSW002194-BMM- XX-A10-RP-EY-0301017).
Water Framework Directive The WFD is an EU Directive (2000/60/EC) transposed in to domestic legislation by the Water Environment (Water Framework Directive) (England and Wales) Regulations 2003 (SI 2003/ 2342). The WFD broadly aims to deliver long-term protection of rivers, estuaries,
6 Ch2m (2018), Environmental Statement, Avonmouth Severnside Enterprise Area Ecology Mitigation and Flood Defence Scheme, Prepared for South Gloucestershire Council, Bristol City Council and the Environment Agency, May 2018.
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Project Number: ENVIMSW002194 coastal areas, groundwater and wetlands, to achieve the best possible environment for people and wildlife. A WFD screening has been carried out within this ES addendum (see Section 8).
3.3 National legislation
Wildlife and Countryside Act The Wildlife and Countryside Act (WCA) 1981 (as amended) consolidates and amends several pieces of national legislation and is the principle mechanism for the legislative protection of wildlife in the UK. The WCA provides protection of certain birds, wild animals and plants, the countryside, national parks and the designation of protected areas, including the protection and management of SSSIs. Measures to prevent the establishment of non- native species are also included in this legislation. The WCA also makes it an offence to disturb, injure or kill listed species of flora and fauna, and requires consideration of the impacts of proposed works on biodiversity.
Countryside and Rights of Way Act The Countryside and Rights of Way (CRoW) Act (2000) amends the WCA. It covers four main areas; access to open countryside, Public Rights of Way (PRoW), nature conservation/wildlife protection and Areas of Outstanding Natural Beauty (AONB). The Act offers protection to PRoWs, increases the protection for SSSIs and strengthens wildlife enforcement legislation.
The Natural Environment and Rural Communities Act The Natural Environment and Rural Communities (NERC) Act (2006) imposes a duty on public authorities to conserve, restore and enhance biodiversity in addition to the statutory protection given to specified sites and species. The Act also lists habitats and species of principal importance for the conservation of biodiversity, which must be afforded a degree of protection.
Environmental Permitting Regulations The Environmental Permitting Regulations 2010 SI2010/675 (as amended) require operators to obtain permits for some facilities, to register others as exempt and provides for ongoing supervision by regulators. The proposed stockpiling will require a Bespoke Environmental Permit in relation to waste, the application for which will be submitted to the Environment Agency separately to the planning application.
3.4 National policy
National Planning Policy Framework The revised National Planning Policy Framework (NPPF) was updated on 19 February 2019 and sets out the government’s planning policies for England and how these must be applied. The revised NPPF replaces the previous March 2012 version and July 2018 revision. The 2019 NPPF and its accompanying Planning Practice Guidance documents set out UK
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Project Number: ENVIMSW002194 government planning policies for England, with a presumption in favour of sustainable development.
3.5 Local policy
South Gloucestershire Local Plan
The new South Gloucestershire Local Plan covers the whole administrative area of South Gloucestershire, from 2018-2036. It will review and eventually replace existing local planning documents, including the: • South Gloucestershire Local Plan: Core Strategy – 2006-2027 (2013); and • South Gloucestershire Local Plan: Policies, Sites and Places Plan.
South Gloucestershire Core Strategy 2006-2027 The Core Strategy is the key planning policy document forming the strategic component of the Council’s new Local Plan and was adopted on 11th December 2013. It sets the detailed spatial strategy for future development in South Gloucestershire up to 2027. The Strategy includes policies and programmes for the general location of new development, its type and scale, and the resources to deliver it, as well as the protection of what is valued about the area. The Core Strategy covers six spatial areas, including Severnside, which is of relevance to this ES addendum.
West of England Joint Spatial Plan 2016 to 2036 The unitary authorities of Bath and North East Somerset, Bristol, North Somerset and South Gloucestershire will jointly prepare a spatial plan which will guide the review and roll-forward of the Local Plans for those areas. The plan is being prepared to enable cooperation on planning issues that cross administrative boundaries. The Plan covers the period 2016-2036.
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Consultation
4.1 ASEA flood defence and habitat creation scheme Table 4-1 below describes the consultation carried out for the associated ASEA scheme.
Table 4-1 : Consultation carried out for the ASEA scheme Stakeholder Engagement Date Summary of engagement Environment Agency (various Workshop June 2016 Broad agreement on ‘hold the line’ approach. disciplines), SGC, BCC, Natural Noted importance of public rights of way in the study area. England, Lower Severn Internal Highlighted need to work with tenant farmers in Areas 4 Drainage Board (IDB), Wessex and 5. Water, Bristol Port, Network Rail, Highways England. Noted preference to not pen the ditches. Need to consider impact of scrapes on groundwater levels. Potential archaeology noted. Importance of understanding wildlife corridors highlighted. Environment Agency (various Workshop September Discussion on various options for flood defences, and on- disciplines), SGC, BCC, IDB, 2016 site and off-site habitat creation. Wessex Water, Network Rail. Noted importance of EIA covering construction impacts on people and wildlife and impacts on landscape and views. Highlighted need for salt marsh botanical surveys. Noted need for eel passes for all structures/outfalls. Noted importance of understanding wider ditch/drainage network. Highlighted importance of ongoing management of habitat areas. Noted need to consider impact of wind turbines and Bristol Airport flightpath. Lower Severn IBD Meeting September Confirmed that penning of the main ditches would not be 2016 acceptable to the IDB. Landowner of existing nature Site visit February Understanding of existing habitat. reserve 2017 Natural England, BCC Meeting February Overall approach understood. ecologists, SGC ecologists 2017 Noted requirement for post construction surveys. Noted importance of considering view from the Severn Way footpath. Noted importance of considering Site of Nature Conservation Interest (SNCI) and wildlife corridor in Area 3. Screening for a Habitat Regulations Assessment required. The scheme will aim to avoid significant adverse impacts on the Severn Estuary multi-designated site. Need to define success factors noted. SGC/BCC planning officers Meeting February Agreed format of application (two applications, with one 2017 shared EIA). Requested screening letter (sent in March 2017). Environment Agency National Meeting April 2017 Agreed approach to reporting scoping, Preliminary Environmental Assessment Environmental Information Report (PEIR) and ASEA ES. and Sustainability Team (NEAS) Landowners Meetings and July 2016 - Access to land for surveys. site visits ongoing Feedback on early options. SGC and BCC County Telecons March European protected species (EPS) licences and ecological Ecologists, and NEAS 2019 - surveys and mitigation works, and discharge of pre- ongoing commencement planning conditions.
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Stakeholder Engagement Date Summary of engagement Natural England Telecons March EPS licences and ecological surveys and mitigation works. 2019 - ongoing Friends of Lamplighters Marsh Site meeting July 2019 Introductions, discussion of proposed scheme and ecological and utilities surveys. Source: Ch2m (2017), EIA Scoping Report, Avonmouth and Severnside Enterprise Area (ASEA) Ecology Mitigation and Flood Defence Report, Appended to the Planning Application Validation Requirements and Environmental Impact Assessment Scoping Request
4.2 Consultation associated with the stockpiling Table 4-2 below describes the consultation carried out for the proposed stockpiling.
Table 4-2 : Consultation carried out for the proposed stockpiling Stakeholder Engagement Date Summary of engagement SGC County Ecologist, NEAS Telecon 21st May GCN licensing approach, requirements to discharge the officer 2019 SGC conditions of the 10- year management plan and the Landscape and Ecological Management Plan (LEMP) and the Area 5 design SGC County Ecologist, NEAS Telecon 4th June The need for a stockpile and proposed locations for this. officer 2019 SGC County Ecologist, NEAS Telecon 14th June Update on documents to be produced for the discharge of officer 2019 planning conditions. 4th July E-mail from SGC County Archaeologist, suggesting 2019 alternative area within Area 5 of the ASEA scheme that may be suitable for stockpiling (refer to Section 2.5 above) SGC County Ecologist, NEAS Telecon 16th August Planning application for stockpile and the need for an ES officer 2019 addendum.
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Population and human health
5.1 Introduction The new EIA Directive (2014/52/EU), which was transposed into UK law in May 2017, now requires the assessment of potential human health impacts resulting from associated developments as part of the EIA process. The potential for the ASEA Scheme to cause impacts on the health of nearby populations was fully taken into consideration within Chapter 8 of the ASEA ES (permissions SPT18/2505/R3F (SGC) and 18/02847/FB (BCC)). Following the decision to relocate the proposed stockpiling to an area of land outside of the red line boundary of the ASEA scheme, the potential for impacts on population and human health need to be re-considered for the storage of material in this new location.
5.2 Methodology Health is defined as ‘a state of complete physical, mental and social well-being and not merely the absence of a disease or infirmity’7. It is assumed that the health demographics, characteristics and determinants within the study area will not have changed since the ASEA ES. This is because the change in location of the stockpile is marginal in comparison to the area previously assessed for impacts on population and human health. A review of the ASEA ES highlighted that the health determinands originally considered within the assessment included:
• Noise and vibration; • Air quality and dust; • Visual disturbance; and • Recreation and amenity. Impacts relating to these health aspects from the proposed stockpile have been reconsidered within this ES addendum. It should be noted that the new stockpile location is present within the SGC boundary and therefore effects raised within the ASEA ES relating to population and human health within the BCC boundary are not considered within this ES addendum. The assessment followed the methodology of the previous ‘population and human health’ chapter undertaken in the ASEA ES and considers the above stated health aspects to predict whether any anticipated changes would result from the relocation of the stockpile. This involved considering the following:
• The aspect of the stockpile causing the change, for example the utilisation of vehicles and plant to construct the stockpile, the presence of the stockpile within the landscape, etc;
7 WHO (World Health Organization), n.d. Definition of Health, Available at: https://www.who.int/about/who-we-are/frequently-asked-questions [Accessed 22 August 2019]
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• The section of the population that might be affected by the change i.e., dense urban area, residents, children, businesses and their staff, etc; and • The residual impact, both positive and negative when taking into account the proposed mitigation measures.
5.3 Baseline The location of the proposed stockpile is the former landfill in Northwick. This location is well screened from human receptors. The Severn Way PRoW passes adjacent to the west of the proposed stockpile area and is currently screened by a row of existing poplar trees and hedgerows (although this vegetation will be removed during the construction phase of the ASEA scheme). To the east of the stockpile location there is a residential property (The Old Piggery), which is separated from the fields proposed to contain the stockpile by the A403 road. Further south of the stockpile location there are more residential and agricultural properties (see Appendix A: Environmental Constraints Plan).
5.4 Previous Assessment The previous assessment on population and human health in the ASEA ES did not highlight any effects specifically relating to the Northwick Landfill area or to stockpiling. It was however highlighted that there is potential for dust in the construction phase to cause adverse effects on population and human health.
5.5 Assessment of Effects Effects assessed are in line with those assessed within the ASEA ES (as outlined in Section 5.2).
Noise and Vibration: Impacts on noise and vibration have been fully considered within Chapter 15 and so are not considered further within this population and human health chapter.
Air quality and dust: Impacts on air quality have been fully considered within Chapter 12 and so are not considered further within this population and human health chapter.
Water Environment: Impacts on the water environment have been fully considered within Chapter 8 and so are not considered further within this population and human health chapter.
Visual disturbance: There is a potential for the visual disturbance to the closest residential building to the stockpile, ‘The Old Piggery’, and to the Severn Way PRoW. These may cause residents and users of the PRoW stress and anxiety. However, mitigation measures will include limiting the height to 2m, which should keep stockpile levels below the hedgerows around the former landfill site and minimise the potential for visual effects. In addition, this stockpile will be
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Project Number: ENVIMSW002194 seeded and therefore once vegetation has established, it will look similar to the surrounding fields, further minimising visual effects. In addition, effects on users of the Severn Way will also be temporary, as users will pass by the area briefly as they walk along the PRoW. During the operational phase of the project, the stockpile will no longer be present as it will have been used to build the earth embankments required as part of the ASEA scheme. Prior to the creation of the stockpile, the topsoil layer will be removed and stored to allow the installation of a geotextile membrane which will protect the landfill cap. During the operational phase, the topsoil will be reinstated on site and reseeded, returning the site to its pre-construction conditions and therefore avoiding any potential operational effects caused by visual disturbance. Taking into consideration the above mitigation and temporary nature of the stockpile and its effects, it is considered that visual disturbance effects on population and human health from the stockpile will be minor adverse. Landscape effects are considered within the landscape chapter of this ES addendum (Chapter 7).
Recreation and Amenity: As described above, the Severn Way PRoW passes to the west of the proposed stockpile location. This will be screened from the stockpile and during the creation of the stockpile, no PRoW closures or temporary diversions will be required. Alterations to nearby PRoW will be required for the ASEA Scheme but have already been taken into consideration within the ASEA ES. The stockpile will be located within agricultural land, for which landowner agreement has been obtained. Therefore, it is considered that the relocation of the stockpile will not cause any adverse effects on recreation. During the operational phase, the stockpile will no longer be present as it will have been used to create the earth embankments as part of the ASEA flood defence. The topsoil layers will be reinstated and reseeded to return the site to its pre-construction conditions. Therefore, it is anticipated for there to be no effect on recreation and amenity during the operational phase.
5.6 Additional Mitigation and Residual Effects Mitigation measures listed within this section are considered to be sufficient to prevent any significant adverse effects from occurring as a result of the stockpile relocation. All effects listed above are temporary and there are no residual effects anticipated.
5.7 Conclusion Overall all aspects of population and human health have been considered in terms of potential effects relating to the relocation of the stockpile. Considering the above likely effects and mitigation that will be put in place, it is anticipated that the effect of the relocation of the stockpile on population and human health is negligible.
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Biodiversity
6.1 Introduction The proposed stockpile location is currently grassland (pasture) fields with a historic use as a landfill, located adjacent to the Severn Estuary SAC, SPA and Ramsar site, and SSSI, but not within these designated sites. It is located more than 200m from the ‘Northwick Warth and Flash’ and the ‘Cake Pill, Aust Warth’ high-tide roost sites (see Appendix A: Environmental Constraints Plan). During ecological surveys carried out on the 15th August 2019, there was no evidence of notable or protected species. None of the hedgerows on the boundary will be removed, with the exception of small-scale pruning vegetation at the existing gateway. Furthermore, a 20m construction exclusion zone (CEZ) will be implemented around the proposed stockpile to avoid root protection zones. The closest 5m of this buffer to the proposed stockpile will be grassland that is maintained at a height of 5cm to deter amphibians and reptiles from entering the site. On completion of the ASEA project, the site will be returned to its current condition.
6.2 Methodology A desk study was undertaken as part of the EcIA (ENVIMSW002194-BMM-XX-A10-RP-EY- 0301009) in accordance with Chartered Institute of Ecology and Environmental Management (CIEEM) Guidelines for EcIA (2018). National and local statutory sites, including LNRs and SSSIs were searched within a radius of 2km from the site boundary and a radius of 10km was applied for international and European conservation sites, including: SACs, SPAs and Ramsar sites. The following field work was undertaken:
• Extended Phase 1 Habitat Survey: This survey was undertaken on the 15th August 2019. All habitats within the survey area were identified and mapped in compliance with the ‘Handbook for Phase 1 habitat survey: a technique for environmental audit’ (Joint Nature Conservation Committee, 2010). The assessment identified the likely presence or absence of badgers, suitable water body breeding habitats for GCNs and other protected and notable species. • Preliminary Roost Assessment for Bats: This survey was undertaken on the 15th August 2019 in accordance with Bat Conservation Trust (BCT) Bat Surveys for Professional Ecologists: Good Practice Guidelines 3rd Edition (Collins ed., 2016). The location of the proposed stockpile was assessed on the actual or potential presence of bats. To determine this, a tree preliminary roost assessment on each individual tree within the area of the proposed stockpile and around the boundary hedges was undertaken. In addition, suitable bat habitats for commuting, foraging and swarming were identified and assessed. Despite the proposed stockpile area containing habitat potentially suitable to support commuting and foraging bats, there is preferential feeding habitat further away from the stockpile which is closer to the SACs designated for bats. Therefore, it is considered unlikely that the proposed stockpile will have any effect on bats. However, adherence to best practice mitigation should be ensured.
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• A Stage 1 HRA (ENVIMSW002194-BMM-XX-A10-RP-EY-0301017), an EcIA (ENVIMSW002194-BMM-XX-A10-RP-EY-0301009), and an Arboricultural Technical Note (ENVIMSW002194-BMM-XX-A10-RP-EN-0301022) have been produced.
6.3 Baseline The location of the proposed stockpile is currently neutral grassland (semi-improved) fields, with a historic use as a landfill, surrounded by hedgerows and trees, with the A403 on the eastern boundary. The western boundary consists of a 15m strip of broadleaved woodland and dense scrub which follows the Severn Way PRoW. There are four designated sites for nature conservation within 5km and two sites designated for bats within 30km of the proposed stockpile. Table 6-1 below lists these statutory designated sites.
Table 6-1: Statutory designated sites Site name Designation Approximate Proximity to the Site Within 5km of Site Severn Estuary Ramsar 21.3m north-west Severn Estuary SAC 21.3m north-west Severn Estuary SPA 21.3m north-west River Wye SAC 3.7km north-west Within 30km of the Wye Valley and Forest of SAC 16.9km north Site Dean Bat Sites North Somerset and SAC 24.3km south Mendip Bats
There are four non-statutory designated sites within 2km of the site. These are listed in Table 6-2 below.
Table 6-2: Non-statutory designated sites Site name Designation Approximate Proximity to the Site Aust to New Passage SNCI (Part of Severn The boundary of this SNCI forms the western Estuary SSSI) boundary of the proposed stockpile with a small area (10m) within the west section of the surveyed area in the southern field. New Passage to Chittening Warth SNCI (Part of Severn 1.5km south-west Estuary SSSI) Fields north of Rifle Range SNCI 700m south-west The Pill, New Passage SNCI 1.1km south-west
Within the EcIA for the proposed stockpile habitats on site were assessed as having the potential to support the following protected species:
• GCN; • Badgers;
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• Bats; • Birds (over wintering and breeding); • Flora; • Hazel dormice; • Invertebrates; • Other mammals; and • Reptiles. Invasive species, including Japanese Knotweed, have been recorded within the local areas and there is potential for these to be found on site.
6.4 Previous Assessment The previous assessment on biodiversity in the ASEA ES did not highlight any effects specifically relating to the Northwick Landfill area or to stockpiling.
6.5 Assessment of Effects A number of potential ecological constraints have been identified concerning designated sites, habitats and protected species including: Severn Estuary SSSI, SPA, SAC, and Ramsar; Aust to New Passage SNCI; Coastal and Floodplain Grazing Marsh; GCN; badgers; bats; birds (over wintering and breeding); flora; hazel dormice; invertebrates; reptiles; and invasive species. If any of the protected species described above are identified during the project, all work must cease immediately and advice be sought from the Ecological Clerk of Works. Consultation with Natural England may be required, which could lead to further surveys and licence applications. As the construction vehicles will be accessing the area from the east, off the A403, via a dedicated access track, no trees will be removed as part of the stockpiling work. The Severn Estuary SPA, SAC, and Ramsar is adjacent to the area of the proposed stockpile, however these sites are not hydrologically connected to the proposed stockpile location. An HRA screening has been carried out to accompany this ES addendum, which concluded the proposed stockpiling will not have a likely significant effect on the qualifying features of the designated sites (BMMJV, 2019). The area of the proposed stockpile comprises grassland (pasture) and boundary hedgerows, which are considered to be of low ecological value. The site therefore hosts a very different habitat composition to those found in the Severn Estuary, which are Estuaries, Mudflats, Sandflats not covered by seawater at low tide, Atlantic salt meadows, Sandbanks which are slightly covered by sea water all the time and Reefs. The western border of the survey area comprises the existing flood embankment earth bund, intact hedgerow and Severn Way footpath, which signal the change in habitat type between the site and Severn Estuary. The western intact hedgerow is over 5m tall and approximately 15m wide forming a thick
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Project Number: ENVIMSW002194 vegetative barrier between the site and the wider environment. In addition, the current earth bund forming the Severn Way footpath creates a further visual barrier between the site and the Severn Estuary SPA, SAC, and Ramsar site. The difference in habitat type and use suggests the habitat in the survey area isn’t functionally linked to the Severn Estuary and the main concern is if the proposed works will cause disturbance to the species within the Severn Estuary. The HRA screening concludes no likely significant effect on the designated sites will occur, as the proposed stockpile location is not hydrologically connected to the designated sites and the noise and working hour restrictions in place will mitigate potential effects from noise. The existing earth flood embankment and dense intact hedgerows will also provide a barrier which reduces noise to the Severn Estuary from the works. The Environmental Constraints Plan (Appendix A) shows a Severn Estuary high tide roosting site within proximity of the Site, namely the Northwick Warth and Flash. The Environmental Constraints Plan also shows a 200m buffer around the high tide roost, which is the approximate area in which works could cause disturbance to the Severn Estuary’s roosting site. However, as the proposed stockpile is located more than 275m south of the Northwick Warth and Flash it is considered that this is sufficient distance to prevent disturbance to this roost site, especially since the southern border is formed by a large intact hedgerow with mature trees. In addition, it is assumed that the sub optimal habitat contained within the site makes it less suitable for overwintering birds, which has been confirmed following an ornithological survey carried out on the 27th and 28th November 2019. A site walkover survey, in the form of an extended Phase 1 Habitat Survey, was carried out on the 15th August 2019. This identified the habitat within the proposed stockpile area to be sub-optimal for protected species, including GCN, reptiles, bats and dormouse. There are no buildings within the site boundary and no trees with suitable bat features were identified. No evidence of badger activity or invasive species were noted during the survey. Rhines located at the field boundaries provide suitable opportunities for water vole, but as the proposed stockpile will be kept a minimum of 20m from the rhines, these will not be affected by the proposed works. An over wintering bird survey visit was carried out on the 27th and 28th November 2019, to confirm the accuracy of the habitat description for these species. Further details of the Phase 1 Habitat Survey are provided in the EcIA. While no evidence of notable species or protected species were recorded during the ecological surveys, the single day survey is likely to only show a snapshot of the ecological constraints on site. Habitats on site have potential to support protected species, however these habitats are sub-optimal. As such, a 5m buffer around the stockpile will be grassland that is maintained to a height of 5cm to discourage amphibians and reptiles from entering the site. Periodic ecological searches of the peripheries of the site will be undertaken and if signs of badger or GCN are discovered, the option of installing GCN and badger fencing should be revisited. Works will be kept 20m from the boundary hedges, to ensure no adverse effects on trees or hedgerows. Prior to works commencing, the grass within the fields will be kept short through grazing, to ensure suitable reptile habitat does not develop
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Project Number: ENVIMSW002194 and a further site walkover will be carried out 4-6 weeks before works commence, to ensure the site is as described in the EcIA and no further constraints have developed. As part of the works, a temporary haul road will be constructed through a small section of the semi-improved grassland. As described above the site is not currently known to support notable or protected species and a site walkover will be undertaken prior to the construction of this haul road to avoid any adverse impacts on ecological features. Once the stockpile is used and removed, the haul road and associated tarmac will be removed, and the site will be returned to its pre-construction conditions.
6.6 Additional Mitigation and Residual Effects As stated above, due to the habitat present on site being sub-optimal for protected and notable species, no ecological fencing will be used on site. However, if signs of GCN and badger are discovered during the construction phase, the option to install fencing should be revisited. It is recommended that the grass up to 5m away from the stockpile should be maintained to a maximum of 5cm from ground level to help deter amphibians and reptiles entering the site. Taking into consideration the 5m of grassland that is to be maintained to a maximum of 5cm, and the recommended 20m CEZ, a 15m buffer of unmaintained grassland between the hedgerow and the site will be present for the duration of the project. Prior to the creation of the stockpile, the topsoil layers will be removed and stored off site, allowing a geotextile membrane to be installed to protect the landfill cap. Prior to the operational phase of the ASEA scheme the geotextile membrane will be removed, and the topsoil will be reinstated and reseeded, returning the site to its pre-construction conditions. No other further surveys are required providing the recommendations in the EcIA and HRA are adhered to and the site will be returned to its current condition. No further mitigation measures to those suggested in the EcIA, HRA, Construction Environmental Management Plan (CEMP) and Environmental Action Plan (EAP) are required. Refer to the EAP for mitigation measures requires for protected species.
6.7 Conclusion The proposed stockpile is not likely to have a significant effect on any of the designated sites, protected species or other ecological features, providing the mitigation measures set out in the EAP are followed and the proposed stockpile is returned to the current conditions once works have finished.
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Landscape character and visual amenity
7.1 Introduction This chapter considers the landscape character and visual amenity impacts of the proposed stockpile, as described in Chapter 2 of this ES addendum.
7.2 Methodology This chapter applies the assessment methodology set out in Chapter 10: Landscape Character and Visual Amenity of the ASEA ES. This was based on current good practice guidance (Guidelines for Landscape and Visual Impact Assessment, 3rd Edition). The proposed stockpile will lie partly within Area 1 of the ASEA scheme, and within the corresponding study area for the assessment of landscape character and visual amenity impacts set out in Chapter 10 of the ASEA ES. The proposed stockpile was previously proposed to be located within Area 5 of the ASEA scheme. The assessments relating to these two areas, Area 1 and Area 5, as set out in Chapter 10 of the published ASEA ES, are therefore considered within this chapter of the ES Addendum. As the proposed stockpile will be returned to agricultural use following construction, there are not expected to be landscape character and visual amenity effects during operation and operational effects are therefore not discussed further within this chapter.
7.3 Baseline It is considered that the landscape character and visual amenity baseline set out in the ASEA ES remains valid for the purposes of this ES addendum, as the study area encompasses the proposed stockpile. This was confirmed by a site visit in September 2019. The visual amenity receptor groups relevant to the proposed stockpile are set out in the ASEA ES, as follows:
• 1.01: Four properties at Old Passage; • 1.02A: People travelling along the New Passage Road; • 1.02B: Users of Public Right of Way to north of Cake Pill; • 1.03: Users of the Severn Way at Cake Pill Outfall; • 1.04A: Users of the Severn Way between Cake Pill and Redwick; • 5.01: Users of the Public Right of Way footpath to north of Cake Pill; • 5.02: Users of the Common Lane Public Right of Way footpath; • 5.03: Agricultural workers in Tanhouse Farm and other farms in Area 5 Scheme; • 5.04: Users of the Public Right of Way footpaths near Northwick; • 5.05: Users of the Bilsham Lane between Ingst and Northwick;
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• 5.06: Users of the A403 between Aust and Northwick; and • 5.07: The Old Piggery, Northwick Pig Farm.
7.4 Previous Assessment The landscape character effects of the construction phase relating to Area 1 and Area 5 were described as follows in the ASEA ES:
• ‘removal of existing vegetation including trees, lengths of hedgerows, scrub and meadow grassland (to include the belt of hybrid black poplar trees south of Cake Pill); • disruption to the recreational use and enjoyment of the landscape due to diversions and construction activities which will detract from the open, tranquil and rural character of Area 1 and 5 Schemes; • localised but extensive exposure of bare earth over the extent of the works; • the presence of construction plant, vehicles, lighting, fencing, compounds, material stockpiles, temporary works and other detracting features in the landscape.’ The visual amenity effects of the construction phase relating to Area 1 and Area 5 were described as follows in the ASEA ES:
• ‘removal of existing vegetation including trees, hedgerows, scrub and grassland; • reduced visibility of the estuary and foreshore in Areas 1 and 3A as a result of construction works and associated elements; • visual intrusion resulting from the presence of construction plant and vehicular movements, earthworks, signage, fencing, material stockpiles, construction compounds and personnel; • obstruction of views in areas adjacent to flood defences and on public footpaths, in particular the Severn Way Long Distance Path, with possible diversions through less visually attractive areas; • potential issues relating to loss of privacy within private properties, as a result of presence of construction plant and operatives as well as various diversions required during construction.’
7.5 Assessment of effects It is considered that the change in location of the proposed stockpile will not alter the description of the construction phase landscape character and visual amenity impacts, or corresponding conclusions regarding significance of effect within the ASEA ES, with the potential for the introduction of a new cumulative effect due to the removal of the poplars and boundary vegetation on the western bounday of the proposed stockpile under the ASEA scheme. This is considered within Chapter 16 Cumulative Effects. All other adverse effects would be temporary during construction only and they are not considered to be significant for the purposes of this ES addendum.
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7.6 Additional Mitigation and Residual Effects Mitigation is embedded within the proposed stockpile design, as follows:
• Retention and protection of existing hedgerows surrounding the stockpile area; • No works will be carried out within 20m of the edge of the fields, which will protect the trees and hedgerows around the perimeter; • Stockpiles will be restricted to a height of 2m above existing ground level; and • Following the construction, the stored topsoil will be reinstated and re-seeded, returning the stockpile area to agricultural land, with application of pasture seed mix to match existing. In addition, the haul road and associated tarmac will be removed and the site returned to its pre-construction conditions. Therefore, it is not anticipated for there to be any landscape character and visual amenity effects from the decommissioning of the proposed stockpile.
7.7 Conclusion It is considered that the proposed stockpile would not alter the description of the landscape character and visual amenity impacts or corresponding conclusions regarding significance of effects within Chapter 10 of the ASEA ES.
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Water Environment, Flood Risk and Water Framework Directive
8.1 Introduction This chapter considers the water environment, flood risk and WFD effects of the proposed stockpile, as described in Chapter 2 of this ES Addendum. There has been no significant change to the baseline water environment in the vicinity of the proposed stockpiling, as presented in Chapter 11 of the ASEA ES. However, when taking into account the changed location of the proposed stockpile, which the ASEA ES assessed in Area 5, the proposed stockpile has moved southwest, closer to the Severn Estuary.
8.2 Methodology The methodology used within this ES addendum is the same as was used for the ASEA ES, as presented in Section 11.3.3 of the ASEA ES. An FRA has been produced to accompany this ES addendum (ENVIMSW002194-BMM-XX-A50-RP-C-0905083). A WFD8 screening assessment has also been undertaken within this chapter, in accordance with Environment Agency guidance ‘Clearing the Waters for All’9, which provides information on completing WFD assessments within estuarine and coastal waters. This guidance recommends that WFD assessments be completed in a 3-stage approach:
• Stage 1 (WFD screening) - an initial assessment to determine if there are any activities associated with the proposed scheme which may impact waterbodies within the vicinity. • Stage 2 (WFD scoping) - a more detailed assessment to identify risks from the proposed development to receptors (within the study area) based on the relevant waterbodies and their quality elements, to identify if any waterbodies will require further detailed assessment. • Stage 3 (WFD impact assessment) - a detailed assessment of waterbodies and activities carried forward from the screening stage, which must include identification of waterbodies, description of the proposed development, methods used to determine impacts, risk of deterioration, and mitigation required.
8.3 Baseline The stockpile will still be in the vicinity of rhines and surface water ditches, although mitigation embedded within the proposed stockpile design will maintain a 20m buffer between the stockpile and the edge of the fields and associated ditches and rhines. The stockpile is not hydrologically connected to nearby European designated sites. With regards to groundwater, it is assumed for the purposes of this ES addendum that the geology underlying the new proposed stockpile location is the same as the location assessed within
8 Water Framework Directive 2000/60/EC 9 Environment Agency (2017) Water Framework Directive assessment: estuarine and coastal waters [online] available at: https://www.gov.uk/guidance/water-framework-directive-assessment-estuarine-and-coastal-waters (last accessed April 2018).
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Project Number: ENVIMSW002194 the ASEA ES and therefore the change in location does not affect the potential impacts and associated effects from those assessed within the ES. Groundwater will therefore not be considered further within this chapter. The other embedded mitigation measures as presented in the ASEA ES also remain unchanged, namely: • Production of a CEMP covering measures to control pollution during construction (as presented in Section 11.5.4 of the ASEA ES); emergency response plans for dealing with flood risk; and ensuring all licences and consents are in place before starting any works; and • Application of the advice in the Environment Agency’s Pollution Prevention Guidelines (PPGs) (withdrawn) and other relevant industry documents such as CIRIA guidelines.
8.4 Previous Assessment Section 11.5.3.1 of the ASEA ES identified the following potential effects during construction, which relate to the proposed stockpiling: “There could be an increased pollution risk from elevated suspended solids which could potentially impact on the physical, chemical and microbiological water quality characteristics of watercourses. Consequent impacts and heavy silt deposition could include: damage to fish gills by sediment particles; impacts on aquatic vegetation by sediment coating of leaves; visual changes to the watercourse; and silting. The mobilisation of silts and sediments could occur during earthworks (i.e. raising the embankments) and the movement of heavy plant and runoff from stockpiles. There is a high likelihood of silt being generated from these activities which will be greater after rainfall events when sediment can be mobilised and washed via the drainage system or directly in runoff from exposed slopes into receiving waters. Runoff may also emanate from poor site drainage provision, washing and cleaning activities and after rainfall events that exceed the capacity of the drainage system.” It is considered that these effects, which were assessed to be of negligible significance in the original ASEA ES, are still applicable to the new location of the proposed stockpile.
8.5 Assessment of Effects
Water Environment In addition to the effects noted above in Section 8.4, as the stockpile will be located on a historic landfill which accepted mixed wastes, there is the potential that the weight of the stockpile could drive out leachate from the contaminated soils, which could flow over the surrounding land via surface run-off and discharge into the rhines that are immediately adjacent to the site. There is no hydrological connectivity between the proposed stockpile and the European designated sites within the Severn Estuary, so it has been concluded that there will not be an impact on these sites from runoff from the site. However in order to
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Project Number: ENVIMSW002194 further reduce the potential for contaminated leachate to reach the surrounding rhines and ditches, the edge of the stockpile will be kept a minimum distance of 20m from the edge of the fields and the ditches and rhines. In addition, a geotextile membrane will be placed on the surface of the ground to protect the landfill cap and silt fences/socks will be used around the perimeter of the site. Water quality monitoring of the rhines will be carried out pre, during and post stockpiling, to ensure no changes to water quality as a result of the works. The water quality monitoring will test for the following determinands:
• Total suspended solids; • Total dissolved solids; • Total petroleum hydrocarbons; • Biochemical and chemical oxygen demands; • Ammoniacal nitrogen; • Nitrate as NO3; • Phosphates; • pH; and • Metals (Pb, Cd, Cu, Zn). Should any of these determinands show elevated levels during the stockpiling operation, then stockpiling may need to stop until the source of the contaminants can be identified and measures put in place to prevent further increases in levels within the rhine, as discussed below in section 8.6. In accordance with the ASEA ES, the rhines and drainage ditches are considered to be receptors of low value, as they are not classified under the WFD and while the ASEA ES did not present any evidence to suggest poor water quality resulting from anthropogenic factors, it is considered likely that there is some degradation as a result of anthropogenic factors. With the mitigation measures listed above, it is considered that the magnitude of the impact on water quality in the rhines and drainage ditches would be minor adverse. The resultant significance of effect is therefore considered to be negligible.
Water Framework Directive A WFD screening assessment has been carried out for the proposed stockpile relocation against the criteria in the following two EA guidance documents:
• Clearing the Waters for All10; and • Protecting and improving the water environment11
10 Environment Agency (2017) Water Framework Directive assessment: estuarine and coastal waters [online] available at: https://www.gov.uk/guidance/water-framework-directive-assessment-estuarine-and-coastal-waters (last accessed April 2018). 11 Environment Agency (2016), Protecting and improving the water environment, Water Framework Directive compliance of physical works in rivers, Position 488_10.
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It is considered that the proposed stockpiling does not meet the criteria in either of these documents as requiring further assessment, i.e. it does not have the potential affect the hydromorphology, biology, water quality, protected areas, or invasive non-native species of estuarine or coastal waters, and no physical works will be carried out in the rhines or watercourses. Further stages of WFD assessment are therefore not considered within this ES addendum.
Flood Risk The primary source of flood risk to the site is tidal flooding. The flood risk posed to the development from surface water, sewers, groundwater, reservoirs and canals sources is considered acceptable in terms of planning policy. Approximately 60% of the site of the proposed stockpile is located within Flood Zone 3, with the remaining area located within Flood Zone 2. The FRA demonstrates that there are no practical alternative sites in Flood Zone 1 for the development of the stockpile. Moreover, it is not practicable to position the stockpile entirely outside the predicted flood extent for the 0.5% Annual Exceedance Probability plus climate change tidal flood events. However, at times of maximum stockpiling, over 50% of the material could be stored above the expected 0.1% plus climate change tidal flood level. It is deemed that the Sequential Test can be been met. The development is considered to be “water-compatible development” and as such the Exception Test is not required. Once the stockpiled material has been utilised, the geotextile membrane will be removed and the topsoil will be reinstated and re-seeded, returning the site to its pre-construction condition. Providing consideration is given to surface water run-off and drainage during construction and operation there will be no increase in flood risk elsewhere. Construction best practice will also be implemented throughout the project to ensure the is no increase in sedimentation or contamination within the surrounding drainage channels and rhines.
8.6 Additional Mitigation and Residual Effects If water quality monitoring shows elevated level of pollutants, indicating that leachate is being driven out of the landfill into the rhines surrounding the proposed stockpiling, then the additional field to the north of the proposed stockpile could be utilised to enable the soil to spread over a larger area, thereby reducing the weight on any one part of the landfill. With the mitigation already designed in and described above, it is considered that residual effects would be negligible.
8.7 Conclusion Effects on WFD were screened out and no re-assessment was therefore deemed necessary, subject to the mitigation measures listed in the EAP being implemented.
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Only one additional potential effect has been identified as a result of the change to the proposed stockpiling location, which relates to the potential for leachate to be driven out from the historic landfill into the adjacent rhines and ditches. However, with the proposed design leaving a minimum 20m buffer between the stockpile and the edge of the fields, the use of a geotextile membrane and silt fences/socks, the proposed water quality monitoring, and the lack of hydrological connectivity between the proposed stockpile and the European designated sites within the Severn Estuary, this effect is considered to be of negligible significance. The FRA carried out for the proposed stockpile concluded that the development can be considered acceptable in terms of planning policy for flood risk.
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Archaeology and cultural heritage
9.1 Introduction This chapter considers the archaeology and cultural heritage effects of the proposed stockpile, as described in Chapter 2 of this ES Addendum. There has been a significant change to the baseline historic environment in the vicinity of the proposed stockpiling, as presented in Chapter 11 of the ASEA ES, in that the proposed stockpile location is on top of a former landfill site.
9.2 Methodology A Desk Based Assessment (DBA) was undertaken for the ASEA scheme which included a study area of 2km surrounding the site, although the ASEA ES assessed the area within the boundary of the ASEA scheme only. As the proposed stockpile location lies within this 2km study area of the DBA, a new DBA has not been undertaken and as for the ASEA ES, this ES addendum will assess effects within the boundary of the proposed stockpile only. The perceived value of cultural heritage receptors for this assessment does not differ from those listed in the ASEA ES.
9.3 Baseline The general area surrounding the Severn Estuary and the proposed stockpile location is well known for its abundance of ridge and furrow systems (an archaeological pattern created by the process of agricultural ploughing). The proposed stockpile location is on top of a former landfill site, meaning the ground below is highly disturbed and any archaeological assets, including ridge and furrow, within the area will have been removed. There are no built heritage assets present in the proposed stockpiling area or the immediate vicinity. There are no buildings present in the proposed stockpiling area. The nearest building to the stockpile area is The Old Piggery B&B, but this building is not listed.
9.4 Previous Assessment The ASEA ES included the following proposed mitigation measures:
• Archaeological monitoring (watching brief) during groundworks for parts of the proposed sea defences; and • Avoidance of direct impacts on historic landscape elements. In addition, the Area 5 reference design has been revised to ensure that ecological mitigation works allows historic landscape elements (ridge and furrow) to be retained as much as possible, highlighting the importance of this heritage asset.
9.5 Assessment of Effects The new location for the proposed stockpile was carefully considered and took into account the potential effects on archaeology and cultural heritage features, including ridge and
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Project Number: ENVIMSW002194 furrow. The proposed location was deemed the most acceptable for archaeology and cultural heritage due to the presence of the former landfill, which means that the ground is already highly disturbed and there is a negligible potential for archaeological or built heritage features to have survived within the area. Additionally, there are no built heritage features in the immediate vicinity which could be affected by the proposed stockpile. There is an existing access track to utilise off the A403 into the stockpiling area, meaning no disturbance to nearby fields containing ridge and furrow will be necessary to enable access. In addition, on completion of the construction phase, the geotextile membrane will be removed, and the topsoil will be reinstated and reseeded, returning the site to its pre-construction conditions. Therefore, the utilisation of this area is considered to have no effect on archaeology and cultural heritage.
9.6 Additional Mitigation and Residual Effects No additional mitigation is required, and no residual effects are anticipated. Given that the proposed stockpile will be on an historic landfill where there is a negligible potential for archaeological or built heritage features, it is considered that the mitigation measures listed in the ASEA ES are also not required.
9.7 Conclusion It is concluded that there are no anticipated effects on archaeology and cultural heritage as a result of the proposed stockpile.
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Geology and Soils
10.1 Introduction The assessment of geology and soils in the ASEA ES scheme found no residual or in- combination effects from any parts of the ASEA scheme that lie within the SGC area, which would be relevant to the proposed stockpile. The ASEA ES identified mitigation measures to reduce the effect of potentially contaminated land and ground compressibility of the River Terrace Deposits. The proposed stockpile is described in Chapter 2.
10.2 Methodology The methodology within the existing ASEA ES has been reviewed and is considered appropriate for use within this ES addendum for the proposed stockpile.
10.3 Baseline In addition to the sources used to inform the ASEA ES, the following report has also been considered:
• BMM JV. 2019. Contaminated Land Risk Assessment – Proposed stockpile Off A403 Severn Road. Ref: ENVIMSW002194-BMM-XX-Z00-RP-SC-0302076 The historical landfill present on site was included as a potential contamination source within the ASEA ES, but it was not included in the broader conceptual ground models. A conceptual ground model specific to the proposed stockpile was produced as part of the Contaminated Land Risk Assessment (CLRA) Report for the ASEA scheme (ENVIMSW002194-BMM-XX-A10-RP-EN-0109002) and is replicated in Table 10-1.
Table 10-1: Conceptual ground model for the proposed development area Strata Description Top (mbgl) Base (mbgl) Topsoil Brown silty CLAY with roots 0.0 0.15 – 0.40 Made Ground - cap material Brown and blue-grey silty CLAY with gravel and roots. 0.0 0.70 – 2.20 (present towards centre of site) Anthropogenic components include brick, concrete, glass and ash. Made Ground - landfill material Black plastic bags with household waste / inclusions: 0.70 - 2.20 >2.90 (present towards centre of site) copper pipes, plastic, timber, textiles, rubber, brick, metal, piping and decaying vegetation. Tidal Flat Deposits (underlies Cohesive unit: Soft to very soft blue grey thinly laminated Depends on Cohesive unit: Topsoil around site peripheries) silty CLAY with occasional pockets of decaying organic the presence/ 12.50 to 25.50 matter. absence of Granular unit: Granular unit: Loose to medium dense grey silty fine to landfill 12.50 – 18.70 coarse SAND material Glacial gravels (locally present) Medium dense to dense slightly silty sandy GRAVEL of 20.70 – 25.60 20.70 – 28.90 sandstone, limestone, mudstone and quartz. Mercia Mudstone Group Very stiff red-brown slightly sandy gravelly CLAY (Grade 18.50 – 29.0 Unproven IV) to very weak sandy silty MUDSTONE (Grade II) occasional bands of buff coloured sandstone.
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The effects associated with the natural geology identified in the conceptual ground model concur with those presented in the ASEA ES and no further assessment has been undertaken. No SSSIs with regard to geology or Regionally Important Geological Sites (RIGS) are present on the site or within the immediate vicinity. The sensitivity of potential environmental receptors given in Table 13.15 of the ASEA ES relating to the Area 5 scheme are considered to be valid for the proposed stockpile. The proposed stockpile is underlain by an historical landfill that was considered to present a moderate negative effect on Area 1 of the ASEA scheme. The effect was greatly reduced as intrusive works were not considered to be required. The BMM JV CLRA considered the likely risks to identified receptors from the proposed stockpile. Contamination risks to geology and soils are low to very low with two identified moderate/low risks, which would be reduced to low where mitigation measures are employed. No significant adverse effects have been added as a result of the proposed stockpile.
10.4 Assessment of Effects It is not anticipated that the proposed stockpile will have a significant adverse effect on the environmental receptors.
10.5 Mitigation Measures The mitigation measures identified in the ASEA ES are not all relevant to the proposed stockpile. Mitigation measures outlined in the ASEA ES and their relevance to the proposed stockpile have been considered in Table 10-2 below.
Table 10-2: Mitigation Measures Mitigation Measure Relevant to the Reasoning stockpile? (Y/N) Preparation of a Soil No The site is underlain by an historical landfill. As part of the construction Resource Plan phase the topsoil (approximately 100mm) will be removed and stockpiled on-site for restoration following completion of the scheme. In-situ soils are not considered for use elsewhere on the Scheme, therefore a Soil Resource Plan is not necessary Further in-situ No The site is underlain by an historical landfill with a cap of between 0.7 and investigation to inform, 2.2m thickness. As historical ground investigation information is available where required, risk for the site further investigation has the potential to damage the integrity of assessment and possible the cap and potentially create a pollutant pathway. As the conclusions of on-site remediation the BMM JV CLRA identified low risks associated with the use of the strategies. proposed stockpile the requirement for further investigation and assessment is not considered necessary. Provision of clean cover No During stockpiling the active areas (stockpiles and haulage routes) will be over potentially impacted covered with either a geomembrane or hard standing (haulage roads) to material, to both provide limit the disturbance of the landfill capping layer and prevent a contaminant a barrier from exposure linkage being created. Upon completion of stockpiling at the site, surface and to provide a suitable soils will be restored to baseline conditions utilising the original stripped growing medium for soils. Baseline conditions will be established during topsoil stripping. The future landscaping. provision of a clean cover is not required. All mitigation measures No These mitigation measures relate to the risks of permanent features. The associated with ground proposed stockpile is to be occupied for a temporary period, therefore these compressibility of the are not relevant. In addition, River Terrace Deposits are at depth beneath River Terrace Deposits. the landfill waste.
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Mitigation Measure Relevant to the Reasoning stockpile? (Y/N) Agreed site procedure to Yes Such measures are considered best practice and should in place to protect report and manage potential receptors against unforeseen contamination. unforeseen contamination which may be encountered during the construction works.
Prior to earthworks commencing on-site, further discussions will be undertaken and it is anticipated that an Environbmental Permit application will be submitted to the Environment Agency separately to the planning application. Soils excavated on-site will be reused in accordance with a CL:AIRE Definition of Waste Code of Practice Materials Management Plan. Therefore, there will be no significant impact from waste movements off-site. To mitigate the effects associated with damaging the integrity of the landfill cap, resulting in potential risks to construction and maintenance workers, the BMM JV CLRA includes the requirement for a geomembrane to be placed over the landfill cap. The geomembrane will sever the pollutant linkage and ensure the potential effects from disturbance of the landfill will be neligable. Prior to the geomembrane being installed, the topsoil layer will be taken off and stored for the duration of the stockpile’s presence. Once the geotextile membrane is removed following the utilisation of the stockpile, this will be replaced and reseeded, returning the site to its pre-construction conditions. If water quality monitoring shows elevated level of pollutants, indicating that leachate is being driven out of the landfill into the rhines surrounding the proposed stockpiling, then the additional field to the north of the proposed stockpile could be utilised to enable the soil to spread over a larger area, thereby reducing the weight on any one part of the landfill. The BMM JV CLRA also highlights mitigation measures that have been considered elsewhere in this ES addendum and the following chapters should be referred to for further information: Chapter 3 Population and Human Health; Chapter 4 Biodiversity; Chapter 6 Water Environment and Chapter 9 Land Use.
10.6 Conclusion Provided all mitigation measures are adhered to, the proposed stockpile will not result in a change to the assessment of effects presented in the ASEA ES for Area 5 and there will no significant effects .
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Land Use
11.1 Introduction This chapter of the ES addendum assesses the potential change in land use as a result of the proposed stockpile of embankment fill material (soil), associated with the construction of the ASEA scheme. The assessment of Land Use in the ASEA ES found minor adverse effects and no in- combination or cumulative effects from the any of the other projects within the SGC area (Areas 1, 3A and 5). It identifies a number of mitigation measures that should be implemented to reduce the effect on agricultural land, including the grazing of wet grassland habitats over winter. This ES addendum has been produced as the originally proposed stockpile location within Area 5 has been ruled out and the alternative locations considered were ruled out due to adverse environmental effects (GCN and the presence of ridge and furrow field systems) and economic costs. Full details are described in Section 2.5.
11.2 Methodology The methodology within the existing ASEA ES has been reviewed and is considered appropriate for use within this ES addendum for the proposed stockpile.
11.3 Assessment
Baseline There are no buildings, community land or development land within the study area. The total area of the proposed stockpile is approximately 20ha. The current land use is agricultural, predominantly grazing. The area is characterised by predominantly low-lying ground, with some small areas of raised land. The land is also characterised by a network of rhines/ditches and hedgerows, of varying quality and density. The poor condition hedgerows, which are due to be retained, are considered to be of low sensitivity. Topographical data (LIDAR) suggests that there a number of ditches crossing the area. The 2010 ALC map classifies this entire area as “Grade 3 - good to moderate” (Figure 8.1). ALC Grade 3 is considered to be of medium sensitivity. The Post 1988 ALC also shows an area (ALCB06293) of “Grade 4” land to the east of the proposed stockpile, however, the rest of Area 5 Scheme has not been classified. During the ecology surveys, it was observed that the area was used for livestock grazing (cattle) and no arable land was identified. It is assumed from site walkovers and aerial imagery that this area would be classified as Grade 3 or Grade 4 agricultural land. ALC Grade 3-4 is considered to be of medium sensitivity.
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Previous Assessment The previous assessment for the ASEA scheme found that there would be a direct, minor adverse effect within Area 5 due to the temporary and permanent loss of agricultural land.
Assessment of Effects There will temporarily be 20ha of ALC grade 3 land changed to stockpile storage during construction. This is a direct minor, adverse effect due to the quality of land and temporary change in land use. There are no land use in-combination or cumulative effects resulting from the proposed stockpile.
Mitigation Once the stockpiled material has been utilised, the geotextile membrane layer will be removed, and the topsoil will be reinstated at the location of the proposed stockpile. This area will then be reseeded, returning the site to its pre-construction conditions once the stockpiling has finished.
11.4 Conclusion There is a direct minor adverse effect due to the temporary change of grade 3 agricultural land. This is not significant.
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Air quality
12.1 Introduction Clean air is extremely important; it is crucial for life, health, the environment and the economy12. Due to the potential for poor air quality to adversely affect human health, legislation is in place to control standards. Legislation and policy relating to air quality remains the same as originally stated in the Scoping Report for the ASEA ES.
12.2 Methodology Impacts of the ASEA scheme on air quality were partially scoped out of the ASEA ES, with the assessment only covering specific effects relating to population and human health. Therefore, in order to establish whether the change in proposed location of the stockpile will have an effect on air quality, a review of the existing air quality chapter within the Scoping Report was made, alongside a review of the population and human health chapter of the ASEA ES.
12.3 Baseline The new location of the proposed stockpiling area is not within an Air Quality Management Area (AQMA). It is approximately 6.5km south east of the Chepstow AQMA and 12km north west of the City of Bristol AQMA. The site is located adjacent to the A403 – a busy road which currently receives high levels of traffic. Due to its remote location, the proposed stockpile location has a limited number of human receptors, including users of the Severn Way PRoW, which passes west of the stockpile area and ‘The Old Piggery’; a residential property to the east of the stockpile location, separated from the stockpile area by the A403 (see Appendix A: Environmental Constraints Plan).
12.4 Previous Assessment Within the existing ASEA Scoping Report, air quality effects relating to the construction of the ASEA scheme were mostly scoped out as it was concluded that any potential adverse effect on air quality would be negligible once standard mitigation measures were implemented. However, there is potential for local air quality to be affected temporarily throughout the construction phase due to vehicle emissions and dust associated with the stockpiling of materials.
12.5 Assessment of Effects Despite the location of the stockpile changing, the new proposed location is still within the SGC boundary and similarities still apply in terms of effects and receptors. Air quality effects on human health i.e. dust and particulate matter, remain scoped in due to vehicle emissions and dust associated with the stockpiling of materials.
12 DEFRA, 2018. Air pollution in the UK 2017.
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The proposed stockpile location is in a remote and open area adjacent to the Severn Estuary and is not within an AQMA. Due to this open location, any dust or vehicle emissions are likely to immediately dissipate and will not cause a lasting adverse effect on local air quality. There are a limited number of human receptors in the immediate area, however best practice mitigation will be put in place, in accordance with the CEMP, to avoid any adverse effects on population and human health. This mitigation may include, although not necessarily be limited to, the following:
• Seeding of stockpiles to prevent the mobilisation of dust and particulates which could impact on receptors within the surrounding area; • Measures to prevent mud soiling the road which could lead to dust generation, as required; • Stockpiles will be created so that the slopes are no steeper than the angle of repose to avoid slippages and the creation of dust; and • A dust management plan will outline measures that could be implemented on site such as tyre washing and hosing down dry areas to prevent dust.
The ASEA ES found that the direct impact of HGVs alone on NO2 concentrations was not expected to be significant and the original recommendation of the use of EURO 5 vehicles (which have a significantly lower emission of NOx) will still be maintained for this new stockpile area. As the change in location of the stockpile from the previously proposed area is minimal, it is anticipated that there will be no change to the previously determined effects. Once the stockpiled material has been utilised, the geotextile membrane will be removed and the topsoil will be reinstated and reseeded, allowing the site to return to its pre- construction conditions. This will avoid any further creation of dust during the operational phase and construction vehicles will no longer be present, removing impacts from vehicle emissions. Taking into account the above-mentioned mitigation measures, it is therefore considered that there will be no significant adverse effects on population and human health from changes to air quality relating to the stockpile.
12.6 Conclusion Dust generated during construction of the stockpile is considered to be the activity with the largest contribution to effects on air quality (particularly in relation to human health), but with the mitigation measures outlined above in place, it is considered that there will be no significant adverse effects on air quality.
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Climate change
13.1 Introduction It has been established that the leading cause of climate change is the release of greenhouse gases produced as a result of combustion, which create a warming effect on the planet. The Intergovernmental Panel on Climate Change has conducted research highlighting the importance of keeping the level of global warming below a 1.5°C rise13 (above pre-industrial levels), to avoid irreversible changes on our planet and climate. It is therefore imperative that construction projects take into consideration potential contributions to rising temperatures and climate change that may occur as a result of the proposed works.
13.2 Methodology Impacts of the ASEA scheme on climate change were scoped out of the original ASEA ES. Therefore, in order to establish whether the new location of the proposed stockpiling will change the anticipated effect on climate change, a review of the existing EIA Scoping Report was made.
13.3 Baseline and Previous Assessment Climate change was scoped out of the ASEA ES as it was considered that not only would the proposed works have a negligible effect on climate change, but the ASEA scheme was necessary to mitigate for predicted sea level rise due to climate change. The ASEA scheme included the proposals for a stockpile, although the stockpile was not specifically assessed within the ASEA ES with regards to its individual contribution to climate change. Despite the relocation of the stockpile area, future climate change predictions for the area remain the same and it is anticipated for sea levels to rise, permitting larger waves to reach the coast, allowing wave ‘overtopping’ of the existing embankment.
13.4 Assessment of Effects The proposed stockpile will not involve any combustion other than within vehicle engines to enable the movement of material. The amount of overall vehicle movements for the proposed stockpile has not changed from that originally considered as the quantity of overall material required for the embankment creation remains the same. The change in location of stockpile is marginal and therefore it is anticipated that any change to the distance of material transported to this stockpile location is negligible. The proposed stockpile location is on top of an old landfill and despite no data being available to show whether emissions were ever generated within the landfill, the avoidance of disturbing the landfill cap will avoid any potential release of methane gases (greenhouse gas with the highest global warming potential) from within the landfill. In addition, the CEMP for the proposed stockpile will outline measures implemented to reduce emissions from the works; such as the use of more efficient EURO 5 vehicles and turning off vehicles and
13 IPCC, n.d. Special Report – Global Warming of 1.5°C. Available at: https://www.ipcc.ch/sr15/
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Project Number: ENVIMSW002194 equipment when not in use. Once the stockpile has been utilised and is no longer present, the geotextile membrane will be removed, the topsoil will be reinstated and reseeded, allowing the site to return to its pre-construction conditions. Overall it should be noted that the use of the stockpiled material will be to raise the existing flood embankment to improve the protection level for the surrounding area to mitigate against the future predicted effects of climate change.
13.5 Conclusion It can be concluded that there is no difference between the previously assessed effects on climate change and the anticipated effects resulting from the change at the location of the proposed stockpile. With the proposed mitigation in place (as outlined in the above sections) it is not anticipated for there to be a significant effect on climate change.
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Major accidents and disasters
14.1 Introduction IEMA defines accidents and disasters as the following14:
• Accident: ‘an uncontrolled occurrence in the course of the construction or operation of a development, leading to serious danger to the environment, which may be either immediate or delayed. For example, this may be a large-scale fire, structural collapse, explosion, or transport accident’; and • Disaster: ‘an external event (i.e. not directly caused by the development) leading to serious danger to the environment, which may be either immediate or delayed. It may result from natural resources, such as coastal flooding, adverse weather, ground movement, or from man-made sources (e.g. escalation of a fire from an adjacent facility, dam collapse etc.)’.
Schedule 4, Section 8 of the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 outlines that an ES should contain ‘A description of the expected significant adverse effects of the development deriving from the vulnerability of the development to risks of major accidents and/or disasters’.
Following the above definitions and information outlined in the existing ASEA Scoping Report, the following major accidents and disasters are considered:
• War and terrorism; • Natural disasters: flooding, earthquakes, hurricanes, tornadoes, tsunami, volcanic eruptions, drought, landslides and avalanches; • Manmade disasters such as rail or motorway accidents; • Industrial accidents such as explosions, chemical spills or fires; • Disease outbreaks; • Events resulting in disruption of: communication systems, transport facilities and health services; • Events resulting in disruption of: supply of money, food, water, energy or fuel; • Events resulting in: loss of human life, human illness or injury and homelessness; and • Damage to property.
14 IEMA, n.d. EIA Quality Mark Article, Available at: https://www.iema.net/assets/uploads/EIA%20Articles/AMEC%20What%20is%20this%20MADness.pdf [Accessed 19.08.19]
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14.2 Methodology The risk of major accidents and disasters was scoped out of the ASEA ES because the main aim of the ASEA scheme is to reduce flood risk for people, property and existing infrastructure and it can therefore be considered to reduce the future risk of a major accident or disaster (in relation to flooding events). The existing ASEA Scoping report was therefore reviewed for the purposes of this ES addendum, and topics considered within the Scoping Report (as outlined in bullet points above) were each considered for the proposed new stockpile location.
14.3 Baseline The new proposed location for the stockpile is not within any zones with high vulnerability to natural disasters. Predicted future trends in sea levels (as discussed in Chapter 6) show that the likelihood of flooding events will increase in the area.
14.4 Previous Assessment The risk of major accidents and disasters was scoped out of the original ASEA ES because the main aim of the ASEA scheme is to reduce flood risk for people, property and existing infrastructure.
14.5 Assessment of Effects The proposed stockpile is not located within an area known for, tornadoes, earthquakes, volcanoes or hurricanes and as such, effects from these are not applicable to this ES addendum. There has been one tsunami recorded in the Bristol area, in 1607, and it is considered extremely unlikely for another tsunami to occur in the area during the period that the proposed stockpile will be in place. While the ASEA scheme will raise the flood defences in the area to protect against future sea level rises due to climate change, the existing embankment in place along the edge of Area 1 will protect against flooding for the duration of the proposed stockpile activity. Once the stockpiled material has been utilised, the geotextile membrane will be removed, and the topsoil will be reinstated and reseeded. This will allow the site to return to its pre- construction conditions. Other major accidents and disasters outlined within Section 14.1 are not considered to be applicable to the proposed stockpile location.
14.6 Additional Mitigation and Residual Effects Measures will be implemented to prevent the accumulation of mud on the local highway network. These measures could include the construction of a haul road, the addition of a rumble strip, a wheel wash and potentially road sweeper.
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14.7 Conclusion It can be concluded that the risk of major accidents and disasters is sufficiently mitigated for in the context of the proposed stockpile. As a result, it is not considered that there will be any effects from major accidents and disasters.
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Noise and Vibration
15.1 Introduction The change to the location of the proposed stockpile will move the access route approximately 850m southwest along the A403. The proposed stockpile will be located approximately 60m from a residential receptor, The Old Piggery, which is located near the southern end of the site (see Appendix A: Environmental Constraints Plan). The relocation of the proposed stockpile has the potential to cause adverse noise effects to this residential receptor due to construction and construction traffic on the A403 entering the access road. The entrance to the stockpile area will be approximately 100m to the south of The Old Piggery. Trucks which access the Stockpile from the south will not pass directly in front of the house before entering the site and therefore only activities within the site have been assessed at the Old Piggery. It is not predicted that the change in stockpile location will result in any change in vibration effects and therefore vibration is not considered further in the assessment.
15.2 Methodology In the ASEA ES, noise was considered as a health determinant under Chapter 5 Population and Human Health. A health determinant if altered, could result in effects on the health and well-being of the local population. A qualitative assessment was carried out to predict the change in health determinant where the following factors were considered:
• The aspect of the proposed stockpile causing the change; • The section of the population that might be affected by the change; and • The residual effect which could be both positive and negative, after considering mitigation. The significance of the identified effect and the corresponding health effect was carried out using professional judgement, based on the concepts of geographic scope and intensity of exposure. In this assessment a more quantitative approach has been taken in line with the guidance outlined below. The potential effects of noise resulting from the proposed stockpile are assessed in terms of the overall significance of the effect in line with the methodology used in British Standard (BS) 5228 ‘Noise Control on Construction and Open Sites’.
Control of Pollution Act 1974 The Control of Pollution Act 1974 provides a mechanism for local authorities to control noise from temporary construction sites. It includes approved codes of practice which should be considered by Local Authorities in taking enforcement action such as the BS5228 ‘Noise Control on Construction and Open Sites’. The Control of Pollution Act 1974 requires that ‘Best Practicable Means’ (as defined in Section 72) are adopted to control construction noise on
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Project Number: ENVIMSW002194 any given site. It makes reference to advice within BS5228 as comprising best practicable means. Sections 60 and 61 provide the main legislation regarding demolition and construction site noise and vibration. If noise complaints are received, a Section 60 notice may be issued by the Local Authority with instructions to cease work until specific conditions to reduce noise have been adopted. Section 61 provides a means for applying for prior consent to carry out noise generating activities during construction. Once prior consent has been agreed under Section 61, a Section 60 notice cannot be served provided the agreed conditions are maintained on-site.
British Standard 5228 Part 1 (Noise) BS5228-1:2009+A1:2014 entitled ‘Code of practice for noise and vibration control on construction and open sites – Part 1: Noise’ provides a methodology for predicting noise levels generated by plant and equipment associated with construction operations. BS5228-1 does not define strict criteria to determine the significance of noise impacts, however it has methods for assessing construction noise. In order to determine the potential for significant change, Method 1 called the A, B, C method from Annex E has been applied for this assessment. This method states the following: “Table E.1 shows an example of the threshold of potential significant effect at dwellings when the site noise level (the noise level generated by the construction site), rounded to the nearest decibel, exceeds the listed value. The table can be used as follows: for the appropriate period (night, evening/weekends or day), the ambient noise level is determined and rounded to the nearest 5 dB.” The receptor is then assigned a Category. The appropriate category is determined using the following three conditions: A) Category A: threshold values (Table 15-1 column 2) to use when ambient noise levels (when rounded to the nearest 5 dB) are less than 65 during Day, 55 during Evening and 45 at Night. B) Category B: threshold values (Table 15-1 column 3) to use when ambient noise levels (when rounded to the nearest 5 dB) are the same as 65 during Day, 55 during Evening and 45 at Night. C) Category C: threshold values (Table 15-1 column 4) to use when ambient noise levels (when rounded to the nearest 5 dB) are higher than 65 during Day, 55 during Evening and 45 at Night. The category value is then compared with the predicted level of construction noise generated by the site. “If the site noise level exceeds the appropriate category value, then a potential significant effect is indicated. The assessor then needs to consider other project-
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Project Number: ENVIMSW002194 specific factors, such as the number of receptors affected and the duration and character of the impact, to determine if there is a significant effect.”
Table 15-1: Example threshold of potential significant effect at dwellings Assessment category and threshold value Category A Category B Category C period Night-time (23.00−07.00) 45 50 55 Evenings and weekends 55 60 65 Daytime (07.00−19.00) and 65 70 75 Saturdays (07.00−13.00) Source: Table E.1 within BS5228-1
NOTE 1 A potential significant effect is indicated if the LAeq, T noise level arising from the site exceeds the threshold level for the category appropriate to the ambient noise level.
NOTE 2 If the ambient noise level exceeds the Category C threshold values given in the table (i.e. the ambient noise level is higher than the above values), then a potential significant effect is indicated if the total LAeq, T noise level for the period increases by more than 3 dB due to site noise.
NOTE 3 Applied to residential receptors only. BS5228-1 provides a table of levels which are often used as limits above which noise insulation would be provided if the temporal criteria are also exceeded. These levels are reproduced in Table 15-2 below and are dependent on the time of day.
Table 15-2: Examples of time periods, averaging times and noise levels associated with the determination of eligibility of noise insulation Noise insulation trigger level
Time Relevant time period Averaging time, T LAeq, T dB 07:00 – 08:00 1 h 70 08:00 – 18:00 10 h 75 Monday to Friday 18:00 – 19:00 1 h 70 19:00 – 22:00 3 h 65 22:00 – 07:00 1 h 55 07:00 – 08:00 1 h 70 08:00 – 13:00 5 h 75 Saturday 13:00 – 14:00 1 h 70 14:00 – 22:00 3 h 65 22:00 – 07:00 1 h 55 Sunday and Public 07:00 – 21:00 1 h 65 Holidays 21:00 – 07:00 1 h 55 Source: Table E.2 within BS5228-1
15.3 Baseline Conditions The location of the proposed stockpile is situated in agricultural land on the Avon Levels and is bordered by the A403 on the east and the Severn Estuary on the west. The dominant source is likely to be local road traffic noise from the A403 and more distant traffic on the M4 and M48.
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The nearest and only potentially affected residence is The Old Piggery which is a farm and Bed and Breakfast which is approximately 50m from the nearest section of the stockpile site boundary near the southern end of the site (see Appendix A).
Defra Noise Mapping indicates that the Daytime LAeq, 16hr level for the area is within the range of 55 to 55.9dB. Even though this LAeq,T level relates to a 16hr period rather than 12hr this is good indication that The Piggery would fall in to Category A of the A,B,C method of BS5228.
15.4 Previous Assessment The results of the Area 5 assessment were stated in the ASEA ES as: “This area includes sparse clusters of housing (sensitivity = low) which may be impacted by noise disturbance during construction (magnitude of impact = minor). Therefore, the overall significance of impact is neutral/slight (negative).”
In terms of individual residences there were no potentially affected residences near the original stockpile site.
Although there is one residence near the new stockpile area it would also be assessed as “sparse clusters of housing (sensitivity = low) which may be impacted by noise disturbance during construction (magnitude of impact = minor). Therefore, the overall significance of impact is neutral/slight (negative).”
15.5 Assessment of Effects
Construction Noise There are two aspects to the potential noise created by the stockpiling area. These are the movement of dump trucks between the stockpile and the flood defence being constructed, and the movement of stockpiled material and loading into dump trucks. It is understood that 14 trucks per hour would access the stockpile. This equates to one truck every 4.3 minutes. Given that it would take more than this time to load a truck it has been assumed that there would always be a truck being loaded throughout the day. Trucks would access the site from the A403, the entrance/exit being approximately 100m south of The Old Piggery. After dumping material on the stockpile, the trucks would circulate within the site and approach the exit travelling down an internal temporary road southward inside the eastern boundary of the site. At their closest point these trucks would pass approximately 50m from The Old Piggery. Noise levels for the stockpile have therefore been assessed on the basis of one dump truck and one loader would be operating at any one time on the stockpile. Noise levels for trucks entering/departing the site have been assessed on the basis of 14 trucks per hour travelling at 10mph (16kmh) within the site.
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The input data for the calculations for each phase, including number of items, percentage on-time and reference within BS5228 Part 1, is presented in the Table 15-3 below.
Table 15-3: Summary of plant for construction works
LAeq at 10m dB BS5228 (**indicates Works Plant reference LAmax) % on-time Quantity Loading lorries: Wheeled 2.27 80 100% 1 Earthworks works Distribution of material: 2.33 81 100% 1 Articulated dump truck ж
The noise levels have been predicted for the ‘worst case’ (closest distance of the works to the sensitive receptor) and the ‘average case’ (middle distance of the works to the sensitive receptor) except where otherwise stated. This is because in actuality, the plant will gradually move around the area potentially affecting The Old Piggery at different intensities and times depending on when the plant is closer and further away from the receptor. The Old Piggery is 50m from the nearest site boundary. The farthest site boundary is over 500m away. Calculations have been conducted at three distances, being ‘worst case’ 50m, ‘average case’ 200m, and ‘best case’ 500m. The results of the calculations are shown below in Table 15-4.
Table 15-4: Stockpiling noise predictions
Scenario Predicted LAeq.T Worst Case 66 Average Case 53 Best Case 43
The assessment of the potential for significant effect is based on the A, B, C method of BS5228 Part 1. The assessment is for daytime hours only (07:00 to 19:00); no evening or night time assessments have been made because this is outside standard working hours. Calculations of noise levels from truck movements have been calculated using the F.2.5 Method for mobile plant using a regular well-defined route (e.g. haul roads) in BS 5228- 1:2009+A1:2014 which provides the equation: LAeq, T = LWA − 33 + 10log10Q − 10log10V − 10log10d Where Q = vehicles per hour V is vehicle speed in Km/h D is distance to the receptor
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This equation has been used to calculate the noise level due to truck movements on the internal haul road as shown in Table 15-5.
Table 15-5: Internal Haul Road Noise Predictions V SWL Q (vehicles per hour) speed (Km/h d distance to receptor LAeq 1hr 110dB -33 14 16km/h 50m Haul Road 110dB -33dB 11dB 12dB 17dB 59dB
Combined with noise levels from stockpiling the overall noise level at The Old Piggery would therefore be 67dB LAeq. Reference to DEFRA Noise mapping shows that the site falls within Category A of the A, B, C method and a significance threshold of 65dB LAeq 12 hr applies. The predicted noise levels are considered to be significant when they exceed the 65dB (daytime threshold). In the worst case therefore, the stockpiling activities and truck movements are likely to result in noise level marginally above 65dBA. Although the time that these worst-case noise levels will prevail is short the exact period is not known. It has therefore been assumed that it would be more than a month. Where the works are considered to have a significant effect mitigation will be required. Best Practicable Means of noise control should therefore be implemented as outlined below. There is also the potential for construction noise to affect birds using the designated sites within the Severn Estuary. This is fully assessed within the HRA and the mitigation measures required are listed in Section 15.6 below.
15.6 Mitigation Mitigation measures will help to reduce the significance of effects on nearby sensitive receptors. Mitigation measures will be employed to ensure that potential noise effects at nearby sensitive receptors due to construction activities are minimised. The preferred approach for controlling construction noise is to reduce source levels where possible but with due regard to practicality. Sometimes a greater noise level may be acceptable if the overall construction time (and therefore length of disruption) is reduced. Construction working hours will be 08:00-18:00 from Monday to Friday and 08:00-13:00 on Saturday. Any requirement to work outside of these normal hours should only occur with prior agreement with SGC. Temporary barriers that remove line of sight (from the receptor to the construction works) could be used to reduce the resultant noise levels from the activities by 10dB and would provide maximum benefit where constructed prior to the commencement of works.
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Alternatively, providing The Old Piggery with noise mitigating glazing for the western façade could provide the same benefit. Construction of the stockpile itself will be used as part of the mitigation. Imported material will be deposited along the eastern side of the stockpile site first to form a bund. The material will then be removed from the western side first when transported for construction. This will ensure a bund remains between the plant movements on the stockpiling site and the receptor for most of the construction period. This will reduce noise effects for the majority of the duration of works. This bund will not screen The Old Piggery from the internal haul road along the eastern boundary, but as the contribution to the overall noise levels from the haul road is 59dB, compliance with the significance threshold of 65dB will still be achieved. Whilst construction noise is likely to be disruptive at The Old Piggery at times, it can be controlled by the implementation of a Construction Noise Management Plan (CNMP), which is included within the Construction Environment Management Plan (CEMP). Incorporated mitigation related to construction noise will be set out within the CEMP. This will identify the series of measures to reduce the environmental effects during the construction period and cover environmental and safety aspects affecting the interests of residents and general public. Specific measures for the mitigation of noise and vibration would be discussed and agreed with South Gloucestershire Council and described within the contractor method statements. The CEMP will also include definitive haul and construction routes leading into and out of the site to ensure this does not cause undue disturbance to local residents. Additional noise mitigation measures may include the following:
• Selecting quiet equipment; • Setting time restrictions on certain noisy activities; • Ensuring equipment is maintained, in good working order, and is used in accordance with the manufacturer’s instructions; • Members of the construction team should be trained and advised during tool box briefings on quiet working methods; • Equipment should not be left running unnecessarily; • Equipment should be fitted with silencers or mufflers; • Use of plant enclosures whenever feasible; • Careful orientation of plant with directional features; • Materials should be lowered instead of dropped from height; • Nearby noise sensitive receptors should be informed in advance of construction activities and kept up to date with progress and changes; • Nearby noise sensitive receptors should be provided a site contact telephone number; the contact should liaise with residents and maintain good rapport;
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• Vehicles should not wait or queue up with engines running on the site or on the public highway; • Deliveries should be managed to prevent queuing of site traffic at access points and the need for vehicles to reverse; • Use of adjustable or directional audible vehicle-reversing alarms or use of alternative warning systems, e.g. white noise alarms; and • Consent under Section 61 of the Control of Pollution Act 1974 will be sought from SGC, if required. Good public relations are invaluable in securing public acceptance of construction noise. People are more tolerant of noise if they understand the reason for it, the likely duration, start and stop dates and that everything is being done to minimise noise levels. Letter drops explaining this will be implemented. A dedicated site contact for the public and a complaint handling procedure will be put in place. In view of the only potentially affected residence being The Old Piggery, it is recommended that personal liaison with the occupant would be the most effective means of avoiding noise complaints. Once the stockpiled material has been utilised, the geotextile membrane will be removed and the topsoil layers will be reinstated and reseeded, allowing the site to return to its pre- construction conditions. During the operational phase there will be no stockpiled material present and no associated construction vehicles, removing any potential effects from noise. It is understood from the ASEA ES that advice given in BS5228 will be followed during construction works. In addition to this, following the above recommendation as well as those given in the CEMP will minimise the potential for significant effects. The magnitude of the impact would be negative moderate, which would result in a significance of the effect as moderate adverse. This would be a significant, but temporary, effect. In order to prevent potential effects on the birds using the designated sites within the Severn Estuary, no works that exceed 55db will be carried out within 200m of a high tide roost (as shown in the Environmental Constraints Plan in Appendix A) within 2 hours either side of high tide, between September and March. This will ensure negligible adverse noise effects on the SAC/SPA/Ramsar site.
15.7 Conclusion The effects of the proposed stockpile have been qualitatively assessed in terms of noise due to construction and construction traffic. For the majority of Area 5, the proposed stockpile does not change the results of the previous assessment. The effects of noise would be limited to one receptor which has been assessed as having a significant effect due to the proximity to the works and the duration of the works being in excess of 6 months. To reduce the significance of the effect it is recommended that in addition to the mitigation methods recommended in the ASEA ES and the CEMP, a construction noise limit of 65 dB LAeq,T at the receptor is implemented. Adhering to this limit would reduce the potential for significant effects and could reduce the overall significance of the effect to moderate. The
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Project Number: ENVIMSW002194 use of stockpiled material to form a noise bund is recommended as outlined above and other mitigation measures may also implemented, as required. These mitigation measures will remove the overall significance of the effect for the duration of the stockpiling activity. Mitigating through the early utilisation of the stockpiled material itself as a noise bund to protect The Old Piggery from noise from later stockpiling is acceptable; mitigation should be undertaken within the first month to reduce the length of the greatest impact to one out of the eight months of anticipated construction. As a result, residual effects from noise would be temporary and considered to be not significant for the purposes of this ES addendum. There will be negligible adverse effects on the designated sites within the Severn Estuary, as restrictions to working hours within 200m of high tides roosts will be implemented.
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Cumulative effects
16.1 Introduction As described in Section 2.1, the proposed stockpiling to which this ES addendum relates is part of the larger ASEA scheme to create wetland habitat and flood defences between Aust and Avonmouth. The cumulative effects of the two projects acting together therefore need to be assessed.
16.2 Methodology The methodology used within this cumulative assessment is the same as that used within the ASEA ES.
16.3 Baseline The ASEA ES considered cumulative effects between the ASEA scheme and the following other developments within the vicinity:
• Bristol Deep Sea Container Terminal; • MetroWest – Portishead Branch Line (MetroWest Phase 1); • Swansea Tidal Power Scheme – Swansea Bay; • Cardiff Tidal Lagoon Project; • Bridgwater Bay Tidal Lagoon; • Hinkley Point C Connection; • Hinkley Point C; • M49 Avonmouth Junction - Due to open December 2019, therefore no potential for overlap; and • M4 Relief Road, Newport – Project cancelled, therefore no potential for overlap.
16.4 Previous Assessment The ASEA ES concluded that all the above schemes would have negligible residual cumulative effects, apart from the Hinkley Point C Connection, which will pass through Area 4 of the ASEA scheme. However, the proposed stockpiling does not lie within Area 4 and the cumulative effects are therefore also considered to be negligible between the proposed stockpiling and the schemes listed above.
16.5 Assessment of Effects In addition to the above, there is the potential for cumulative effects from the proposed stockpiling and the ASEA scheme as the two are linked developments and will be carried out at the same time. Table 16-1 below assesses the potential cumulative effects between the proposed stockpiling and the ASEA scheme.
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Table 16-1: Potential cumulative effects between the proposed stockpiling and the ASEA scheme Type of receptor and Potential effect Mitigation Residual effects value Population and human None Not required None health Biodiversity Noise from vehicles on high tide roosts Timing restrictions on works. Work that exceeds 55dBA will not be undertaken two None hours either side of high tide within 200m of the high tide roosts between October and April. Landscape character Visual effects from loss of poplars and Limit stockpile height to 2m, to keep it below the level of existing retained Minor adverse (not and visual amenity boundary vegetation hedgerows. significant) Water environment None Not required None Archaeology and cultural None Not required None heritage Geology and soils None Not required None Traffic and transport None Not required None Air quality None Not required None Climate change None Not required None Major accidents and None Not required None disasters Noise and vibration Noise from vehicles on the Old Piggery Listed within CEMP None Noise from stockpiling operations on the Timing restrictions on works. Work that exceeds 55dBA will not be undertaken two designated sites within the Severn Estuary. hours either side of high tide within 200m of the high tide roosts between October and April.
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16.6 Additional Mitigation and Residual Effects No additional mitigation is required.
16.7 Conclusion Providing the mitigation measures, as summarised in this ES addendum and listed in full in the EAP, are followed, it is considered the projects will not have a significant cumulative effect and no significant residual cumulative effects are anticipated.
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Project Number: ENVIMSW002194 Conclusion
17.1 Introduction This section summarises the potential effects identified in this ES addendum and highlights the mitigation measures required.
17.2 Summary A summary of each chapter within this ES addendum is provided below, followed by an overall conclusion.
Population and Health It is assumed that the health demographics, characteristics and determinants within the study area will not have changed since the ASEA ES. All aspects of population and human health have been considered in terms of potential impacts relating from the relocation of the stockpile. These aspects, the associated effects and mitigation measures are shown in Table 17-1 below.
Table 17-1: Population and health aspects, effects and mitigation measures Aspects Effects Mitigation measures Noise and Vehicle movements required to create Refer to Noise and Vibration Chapter’ vibration and utilise the proposed stockpile. Air quality and Refer to Air Quality Chapter Refer to Air Quality Chapter dust Visual Potential to cause resident at ‘The Old The stockpile will be limited to a maximum height of 2m which disturbance Piggery’ stress and anxiety should keep the stockpile below the levels of the hedgerow
Potential to cause visual impact from The stockpile will be seeded, as such, once vegetation has the Severn Way PRoW users (to the established, it will look similar to the surrounding fields. west of the Stockpile) Once the stockpile has been removed, the geotextile membrane will be removed, and the topsoil will be reinstated and re-seeded to return the site to its pre-construction conditions.
Recreation and Potential to cause stress and anxiety to No PRoW closures or temporary diversions will be required amenity the Severn Way PRoW users (to the and the stockpile will be largely screened from the PRoW by west of the proposed stockpile) existing vegetation. Once the stockpile has been removed, the geotextile membrane will be removed, and the topsoil will be reinstated and re-seeded to return the site to its pre-construction conditions.
Providing the mitigation measures are adhered to, it is anticipated that the effect of the relocation of the stockpile on population and human health will be negligible.
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Biodiversity The proposed stockpile location is currently agricultural land, predominately grazing fields with a historic use as a landfill, located to adjacent to the Severn Estuary SAC, SPA and Ramsar site, and SSSI, but not within it. An HRA, EcIA and Arboricultural Technical Note have been produced to support this application. A number of potential ecological constraints have been identified concerning designated sites, habitats and protected species including: Severn Estuary SSSI/SPA/SAC/Ramsar, Aust to New Passage SNCI, Coastal and Floodplain Grazing Marsh, birds (over wintering and breeding), flora and invertebrates. The following mitigation measures will be implemented:
• Work that exceeds 55dBA will not be undertaken two hours either side of high tide within 200m of the high tide roosts between October and April; • The provision of a 5m buffer of rough grassland surrounding the stockpile that will be maintained to a height of 5cm will discourage amphibians and reptiles from entering the site; • A 20m construction exclusion zone will be established around retained trees and hedgerows, if required fencing to British Standard BS 5837:2012 will be used; • A site walkover 4-6 weeks before works commence is required to ensure the site is as described in the EcIA and no further ecological constraints have developed; • If any protected species are identified during the project, all work must cease immediately and advice be sought from the Ecological Clerk of Works, consultation with Natural England may also be required; and • Removal of the geotextile membrane and reinstatement and reseeding of the topsoil, along with the removal of the haul road and associated tarmac post construction to return the site to its pre-construction conditions. The proposed stockpile is not likely to have a significant effect on any of the designated sites. It is not likely to have a significant effect providing the mitigation measures are followed and the site is returned to the current conditions, as is planned.
Landscape and Visual The proposed stockpile will be located partially within Area 1 of the ASEA scheme, as such the corresponding study area for the assessment of landscape character and visual amenity effects are as assessed in the ASEA ES. The following mitigation measures will be implemented:
• Retention and protection of existing hedgerows surrounding the stockpile area. • No works will be carried out within 20m of the edge of the fields, which will protect the trees and hedgerows around the perimeter;
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• Stockpiles will be restricted to a height of 2m above existing ground level; and • Following the construction, the removal of the geotextile membrane, the removal of the haul road and associated tarmac and reinstatement and reseeding of the stockpile area to agricultural land, with application of pasture seed mix to match existing. It is considered that the scheme would not alter the description of landscape character and visual amenity impacts or corresponding conclusions regarding significance of effect within Chapter 10 of the ASEA ES. It is therefore considered that there would be temporary adverse effects during construction, although these would not continue into operation and are therefore not considered to be significant for the purposes of this ES addendum.
Water Environment, Flood Risk and Water Framework Directive There has been no significant change to the baseline water environment in the vicinity of the proposed stockpiling, which will still be in the vicinity of rhines and surface water ditches. The following mitigation measures will be implemented:
• 20m buffer between the stockpile and the edge of the fields and the associated ditches and rhines; • A geotextile membrane will be placed on the surface of the ground to protect the landfill cap and silt fences/socks will be used around the perimeter of the site; • Water quality monitoring will be carried out; • Production of a CEMP to cover measures to control pollution during construction; emergency response plans for dealing with flood risk; and ensuring all licences and consents are in place before starting any works; • Application of the advice in the EA’s PPGs (withdrawn) and other relevant industry documents such as CIRIA guidance; • If water quality monitoring shows elevated level of pollutants, indicating that leachate is being driven out of the landfill into the rhines surrounding the proposed stockpiling, then the additional field to the north of the proposed stockpile could be utilised to enable the soil to spread over a larger area, thereby reducing the weight on any one part of the landfill; and • Removal of the geotextile membrane and reinstatement and reseeding of the topsoil post construction to return the site to its pre-construction conditions. Providing the above mitigation measures are adhered to, it is considered that the proposed stockpile will have a negligible effect.
Archaeology and Cultural Heritage There are no built heritage assests present in the proposed stockpiling area or the immediate vicinity. Furthermore, the proposed stockpile location is on a historic landfill, as such the underlying ground is highly disturbed and any archaeological assets within the area will have been removed.
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 66
Project Number: ENVIMSW002194
The proposed stockpiling will therefore have no effect on archaeology and cultural heritage, and as such no mitigation measures are required.
Geology and Soils The proposed stockpile is located on a former landfill, however the use of a geotextile membrane between the proposed stockpile and the ground surface works will ensure there is no disturbance to the landfill cap. No contaminated material will be imported onto site, and therefore the only potential contamination source relating to the stockpile is the risk from surface run-off. The following mitigation measures will be implemented:
• A geotextile membrane will be placed on the surface of the ground to protect the landfill cap; • The stockpile will be seeded to prevent surface run-off; • Production of a CEMP to cover measures to control contamination; and • Removal of the geotextile membrane, removal of the haul road and reinstatement and reinstatement and reseeding of the topsoil post-construction, to return the site to its pre-construction conditions. Provided all mitigation measures are adhered to, the proposed stockpile will not result in a change to the assessment of effects presented in the ASEA ES. The assessment does not include any signifcant effects but does include direct and indirect minor, adverse effects that have been scoped out.
Land Use The proposed stockpile location is currently agricutural land, predominately used for livestock grazing. The temporary land use change of 20ha of ALC grade 3 land to stockpile storage during construction is considered to be a direct minor, adverse effect due to the quality of land and the temporary change in land-use. The location of the proposed stockpile will be returned to its pre-construction conditions once the stockpiling is finished (removal of the haul road and geotextile membrane), as such the temporary effect is not considered to be significant.
Air Quality The proposed stockpile is not within an AQMA and is located adjacent to the A403, which is a busy road with existing high volumes of traffic. The proposed stockpile will be located in a remote and open area adjacent to the Severn Estuary, as such any dust or vehicle emissions are likely to immediately dissipate. There are a limited number of human receptors in the immediate area, and in accordance to the CEMP, mitigation measures will be implemented to reduce the impact on local air quality:
• Seeding of stockpiles to prevent mobilisation of dust and particulates;
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 67
Project Number: ENVIMSW002194
• Stockpile will be created so that the slopes are no steeper than the angle of repose to avoid slippages and the creation of dust; • A dust management plan will outline measures which could include tyre washing, rumble strips and hosing down dry areas to prevent dust; and • Removal of the geotextile membrane and reinstatement and reseeding of the topsoil post construction to return the site to its pre-construction conditions. The largest activity which will contribute to effects on air quality (particularly in relation to human health) is the potential for dust to be generated during construction of the stockpile. Providing the suggested mitigation measures as outlined in the CEMP are implemented, it is considered that there will be no significant adverse effects on air quality.
Climate Change Impacts of the ASEA scheme on climate change were scoped out of the ASEA ES as not only would the proposed stockpile have a negligible effect on climate change, but the ASEA scheme was necessary to mitigate for predicted sea level rise due to climate change. The proposed stockpile would not involve any combustion other than within vehicle engines to enable the movement of material, and the amount of overall vehicle movements for the proposed stockpile has not changed from that originally assessed. The CEMP outlines measures implemented to reduce emissions from the works, including but not limited to the following mitigation measures:
• Motion sensor lighting and ensure lights are turned off when not in use; • Ensure plant is well maintained to maximise fuel efficiency and reduce CO2; • Switch off engines and do not leave vehicles idling unnecessarily; • Avoid inefficient and oversized machines; and • Removal of the geotextile membrane and reinstatement and reseeding of the topsoil post construction to return the site to its pre-construction conditions. It can be concluded that there is no difference between the previously assessed effects on climate change and the anticipated effects resulting from the change in location of the proposed stockpile.
Noise and Vibration • The proposed stockpile is located 60m from a residential receptor, who has the potential to experience adverse noise effects. There are two aspects to the potential noise created by the proposed stockpiling area: • The movement of dump trucks between the stockpile and the flood defence being constructed; and • The movement of stockpiled material and loading into dump trucks.
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 68
Project Number: ENVIMSW002194
The proposed stockpile was assessed for three scenarios; worst case, average case and best case. The assessment is for daytime hours only (07:00 to 19:00); no evening or night time assessments have been made because this is outside standard working hours. A CEMP has been produced to accompany this ES addendum, which sets out mitigation measures to reduce the impact of noise and vibration on receptors. These mitigation measures include, but are not limited to, the following:
• Construction working hours are 08:00-18:00 from Monday to Friday and 08:00-13:00 on Saturday; • Temporary barriers that remove line of sight would be likely to reduce the resultant noise levels and could be installed, if required; • Imported material should be deposited along the eastern side of the stockpile site first to form a bund to protect the properties in Northwick, particularly the Old Piggery; • Material should be removed from the western side first when transported for construction, this will ensure a bund remains between the plant movements and the receptor; and • A construction noise limit of 65 dB LAeq,T at the the Old Piggery. These mitigation measures will be used to reduce the overall significance of the effect to moderate, for the duration of the stockpiling activity. This would be a significant, but temporary effect.
Cumulative Effects The proposed stockpiling is part of the larger ASEA scheme, which will create wetland habitat and flood defences between Aust and Avonmouth. The noise and vibrations from vehicles on site have the potential to affect the high tide roosts in the Severn Estuary, however mitigation measures have been implemented to reduce this effect. The cumulative effects of the two projects acting together were assessed and it is considered to not have a significant effect and no residual cumulative effects are anticipated.
17.3 Overall Conclusion The categories considered to have the potential to have significant effects are:
• Air Quality; • Biodiversity; • Noise and vibration; and • Water. However, providing the mitigation measures as outlined in this ES addendum and associated CEMP are adhered to, the proposed stockpile is not considered to have significant effects, other than a temporary significant effect for noise.
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 69
Project Number: ENVIMSW002194 Glossary
Air quality management Area defined by the local authority as an area requiring management because area (AQMA) air quality levels do not meet national air quality objectives
Area of Outstanding Areas formally designated under the National Parks and Access to the Natural Beauty (AONB) Countryside Act (1949) to protect parts of the countryside of high scenic quality that cannot be selected for National Park status as they do not have
opportunities for outdoor recreation. The Countryside Agency is the government agency responsible for designating AONBs and advising the government.
Avonmouth Severnside An area in the west of England, designated as an Enterprise Area to recognise Enterprise Area (ASEA) its internationally significant industrial location and a strategically important employment area.
Baseline A description of the present state of the environment with the consideration of how the environment would change in the future in the absence of the plan/programme/project as a result of natural events and other human activities.
Conservation Area An area designated under the Town and Country Planning Act, 1990 to protect its architectural or historic character.
Countryside and Rights This Act applies to England and Wales and has five parts: - of Way (CRoW) Act 2000 • Access to the countryside • Public rights of way and road traffic
• Nature conservation and wildlife protection • Areas of outstanding natural beauty • Miscellaneous and Supplementary This act increases the protection to Site of Special Scientific Interest and Environment Agency plans/programmes/projects must gain consent for works in or near these sites.
Cumulative Effects The combined effects of several projects within an area, which individually are not significant, but together amount to a significant effect.
Department for The government department responsible for flood management policy in Environment, Food and England. Rural Affairs (DEFRA)
Ecological Impact An assessment of the potential effects of a proposed development on species, Assessment (EcIA) habitats and sites that are of value to conservation or protected by national and/or international legislation.
Environmental Action A standalone report or section within another environmental impact assessment Plan (EAP) document which ensures that constraints, objectives and targets set in the main Environmental Report/Statement are actually carried out on the ground.
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 70
Project Number: ENVIMSW002194
Actions are separated into those to be carried out before, during and after construction.
Environmental Impact EIA is an assessment process applied to both new development proposals and Assessment (EIA) changes or extensions to existing developments that are likely to have significant effects on the environment. The EIA process ensures that potential effects on the environment are considered, including natural resources such as water, air and soil; conservation of species and habitats; and community issues such as visual effects and impacts on the population. EIA provides a mechanism by which the interaction of environmental effects resulting from development can be predicted, allowing them to be avoided or reduced through the development of mitigation measures. As such, it is a critical part of the decision-making process. www.iema.net/eiareport
Environmental Statement The document produced to describe the environmental impact assessment (ES) process where statutory environmental impact assessment is required.
ES addendum Additional material produced following the publication of an existing ES (i.e. an update).
Flood alleviation scheme Scheme designed to reduce the risk of flooding in a given area (FAS)
Flood defence A structure (or system of structures) that reduce flooding from rivers or the sea
Great crested newt The largest newt species in the UK, which during the breeding season develops (GCN) a crest. This is a European protected species.
Geotextile membrane A piece of fabric inserted into the ground to form a protective membrane layer.
Habitats Directive EC Directive (92/43/EEC) on the Conservation of natural habitats and of wild flora and fauna. Implemented (with the Birds Directive (79/409/EEC)) in the UK as the Conservation (Natural habitats and wild flora and fauna) Regulations (1994). This establishes a system of protection of certain flora, fauna and habitats considered to be of International or European conservation importance. Sites are designated as Special areas of conservation (SACs), special protection areas (SPAs) and/or Ramsar sites. Any developments in or close to these designated areas are subject to the Habitat Regulations for approval of English Nature. Together these sites are referred to as the Natura 2000 network.
Landfill A method of disposing of waste into an excavated pit.
Local Nature Reserve Nature reserves designated under the National Parks and Countryside Act (LNR) (1949) for locally important wildlife or geological features. They are controlled by local authorities in liaison with English Nature.
Marine Management An executive non-departmental public body established under the Marine and Organisation (MMO) Coastal Access Act 2009 with responsibilities including marine licensing and working with Natural England and others to manage a network of marine protected areas (marine conservation zones and European marine sites).
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 71
Project Number: ENVIMSW002194
Mitigation measures Actions that are taken to minimise, prevent or compensate for adverse effects of the development.
Natural England (NE) NE is an Executive Non-departmental Public Body responsible to the Secretary of State for Environment, Food and Rural Affairs. Its purpose is to protect and improve England’s natural environment and encourage people to enjoy and get involved in their surroundings. Its aim is to create a better natural environment that covers all of our urban, country and coastal landscapes, along with all of the animals, plants and other organisms that live with us.
Preliminary roost A ‘walkover survey’ by a suitably qualified ecologist to inspect an area to assessment for bats determine whether there is any evidence of / potential for roosting bats.
Ramsar site Wetland site of international importance listed under the Convention on Wetlands of International Importance under the Conservation of Waterfowl Habitat (Ramsar) Convention 1973.
Ridge and furrow A form of Medieval and later cultivation that produced a ‘corrugated’ pattern of earthworks within field systems.
Rhine A drainage ditch, or canal used to turn areas of wetland at around sea level into useful pasture.
Scoping The process of deciding the scope or level of detail of an EIA. During this stage the key environmental issues (likely significant effects) of a project/strategy are
identified so that the rest of the process can focus on these issues. Issues may result from the proposal itself or from sensitivities of the site.
Screening The process of deciding which developments require an EIA to be carried out and whether this will be statutory.
Screening opinion Statutory opinion from the competent authority as to whether a proposed project requires statutory EIA according to the Environmental Impact Assessment Regulations.
Site of Special Scientific Nationally important sites designated for their flora, fauna, geological or Interest (SSSI) physiographical features under the Wildlife and Countryside Act (1981) (as amended) and the Countryside Rights of Way Act (2000).
Special Area for Sites of European importance for habitats and non-bird species. Above mean Conservation (SAC) low water mark they are also SSSIs.
Special Protection Area An area designated for rare or vulnerable birds, or migratory birds and their (SPA) and proposed habitats, classified under Article 4 of the EC Directive on the Conservation of Special Protection Area Wild Birds (79/409/EEC). They are also SSSIs. Proposed sites receive the (pSPA) same protection as fully protected sites
Stockpile A large accumulation of material (earth).
Sustainable development A concept defined by the Brundtland Report (1987) as “Development that meets the needs of the present without compromising the ability of future generations to meet their own needs”
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 72
Project Number: ENVIMSW002194
Water Framework EC Directive (2000/60/EC) on integrated river basin management. The WFD Directive (WFD) sets out environmental objectives for water status based on ecological and chemical parameters, common monitoring and assessment strategies, arrangements for river basin administration and planning and a programme of measures in order to meet the objectives.
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 73
Project Number: ENVIMSW002194 Appendices
Appendix A: Environmental Constraints Plan
Stockpile at land off A403 at Northwick – ES Addendum S8 – Shared for client review, comment and/or acceptance Revision P02 74 Key plan !!"¢ !"¢
Cake Pill Outfall Key to symbols Northwick stockpile Site of Special Scientific Interest The Old Piggery Bed (SSSI) and Breakfast Severn Estuary ! Outfall Special Area of Conservation (SAC), XW Bat record Severn Estuary Special Protection (SAC, SPA, XY Bat roost Area (SPA), and Ramsar site) Ramsar site (shared 20m buffer around bat boundaries with roost project area)
Severn Confirmed great Ridge and furrow Estuary XW crested newt pond (SSSI) Historical landfill 250m buffer around great crested newt Authorised landfill ponds
High tide roost site
200m buffer around high tide roost sites
Notes 1. For information only, not for construction. 2. Proposed scheme layout is representative at the date of drawing issue. Drawing will be revised, if required, following design updates. 3. Contains, or is based on, information supplied by Natural England.
P03 22/11/19 JF Stockpile boundary amended CP PE The Old Piggery P02 04/11/19 JF Bed and Breakfast added CP PE Rev Date Drawn Description Ch'k'd App'd
The Old Mott MacDonald Piggery Bed 10 Temple Back and Breakfast Bristol BS1 6FL United Kingdom T (0) 117 906 9500 W mottmac.com
Client
Title Northwick ASEA Ecology & Flood Mitigation Scheme Warth and Stockpile at land off A403 at Northwick Flash Environmental Constraints Plan
Originator J Faber JF Tech Check C Postlethwaite CP Content Check E Haggett EH Coordination A Kirby AK GIS Check T Ruff TR Approved P Easton PE Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Scale at A3 Status Rev Security
© Mott MacDonald Ltd. Metres 1:5,000 INF P03 STD Contains Ordnance Survey data © Crown copyright and database rights 2018 Ordnance Survey. All rights reserved. Environment Agency, 100026380. 0 40 80 120 160 200 Drawing number This document is issued for the party which commissioned it and for specific purposes connected with the captioned project only. It should not be relied upon by any other party or used for any other purpose. We accept no responsibility for the consequences of this document being relied upon by any other party, or being used for any other purpose, or containing any error or omission which is due to an error or omission in data supplied to use by other parties. ENVIMSW002194-BMM-XX-A10-DR-EN-0302078 C:\Users\fab69119\Mott MacDonald\ASEA - External Working Area - 2.3.9 GIS\Workspaces\Env Constraints Plan\P03\ASEA_Env_Constraints_Plan_Area1_Northwick_Stockpile_P03.mxd