10 AIR QUALITY. Introduction. Policy and Guidance

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1 Air Quality Assessment 10 AIR QUALITY Introduction 10.1 This report describes the potential air quality impacts associated with the proposed expansion of Magna Park Lutterworth (MPL). The assessment has been carried out by Air Quality Consultants Ltd on behalf of IDI-Gazeley Ltd (IDI-G) The proposed development is for a building adjacent to the existing park (hereinafter referred to as Magna Park II Plot 1) and comprises the erection of a single building of up to 90,000 sq m for B8 (storage and distribution) use, including ancillary B1 (office) floorspace, together with associated fuelling and vehicle washing facilities, the creation of a new junction and new access from Mere Lane and the existing Magna Park, associated roads, parking for HGVs and cars, servicing areas, and landscaping (including tree planting as part of the proposed landscape strategy). The expected height of the building will be up to 23 m The proposed development lies close to an Air Quality Management Area (AQMA) declared by Harborough District Council (HDC) for exceedences of the annual mean nitrogen dioxide objective. The proposed development will lead to an increase in traffic on the local roads, which may impact on air quality at existing residential properties. The main air pollutants of concern related to traffic emissions are nitrogen dioxide and fine particulate matter (PM 10 and PM 2.5 ) There is also the potential for the construction activities to impact upon both existing and new properties. The main pollutants of concern related to construction activities are dust and PM This report describes existing local air quality conditions (2014), and the predicted air quality in the future assuming that the proposed development does, or does not proceed. The assessment of traffic-related impacts focuses on 2016, which is the anticipated year of scheme opening, as well as the future year of 2031, to consider the long-term impacts. The assessment of construction dust impacts focuses on the anticipated duration of the works This report has been prepared taking into account all relevant local and national guidance and regulations, and follows a methodology agreed with Harborough District Council (HDC). Policy and Guidance Air Quality Strategy 10.7 The Air Quality Strategy published by the Department for Environment, Food, and Rural Affairs (Defra) provides the policy framework (Defra, 2007) for air quality management and assessment in the UK. It provides air quality standards and objectives for key air pollutants, which are designed to protect human health and the environment. It also sets out how the different sectors: industry, transport and local government, can contribute to achieving the air quality objectives. Local authorities are seen to play a particularly Final Report June

2 Air Quality Assessment important role. The strategy describes the Local Air Quality Management (LAQM) regime that has been established, whereby every authority has to carry out regular reviews and assessments of air quality in its area to identify whether the objectives have been, or will be, achieved at relevant locations, by the applicable date. If this is not the case, the authority must declare an Air Quality Management Area (AQMA), and prepare an action plan which identifies appropriate measures that will be introduced in pursuit of the objectives. Planning Policies National Planning Policy 10.8 National planning policy in England is contained within the National Planning Policy Framework (NPPF, 2012) which was published in March The specific policies of the NPPF that relate to issues of air quality are set out below Paragraph 17 states that planning should contribute to conserving and enhancing the natural environment and reducing pollution Paragraph 109 states that the planning system should contribute to and enhance the natural and local environment by preventing both new and existing development from contributing to or being put at unacceptable risk from, or being adversely affected by, unacceptable levels of air pollution Paragraph 124 states that planning policies should sustain compliance with, and contribute towards, EU limit values or national objectives for pollutants, taking into account the presence of Air Quality Management Areas and cumulative impacts on air quality from individual sites in local areas. Planning Practice Guidance In March 2014, the Government announced the launch of the Planning Practice Guidance (PPG) website (DCLG, 2014). The PPG is intended to be read alongside the NPPF and set out below is the guidance that is most relevant to consideration of air quality Part ID32 of the PPG gives more detailed guidance on the relevance of air quality to a planning decision. Paragraph 005 (ID: ) identifies where air quality could be relevant to a planning decision. Considerations include changes in traffic in the vicinity of the proposed development site or further afield, introduction of new point sources of air pollution, construction phase impacts, and the impact on biodiversity. Paragraph 006 (ID: ) states where there are concerns about the air quality, the local planning authority may want to know about the baseline local air quality, whether the proposed development could significantly change air quality, and/or whether there is likely to be a significant increase in the number of people exposed to the problem Paragraph 007 (ID: ) states that assessments should be proportionate to the nature and scale of development proposed and the level of concern about air quality, and because of this are likely to be location specific. Paragraph 008 (ID: Final Report June

3 Air Quality Assessment ) identifies that should mitigation measures be necessary they need to be location specific and proportionate to the likely impact. Local Policies The development plan comprises the adopted Harborough District Core Strategy (HDC, 2011) and the saved policies of the Harborough District Local Plan (HDC, 2007). The relevant local planning policies in respect of air quality are set out below. Harborough District Core Strategy Policy CS14 of the Core Strategy states that transport interventions associated with additional development in and around Lutterworth will focus on improving air quality and reducing the adverse impacts of traffic flows in the town centre. This will be achieved by measures including resisting development that would result in additional HGVs passing through the town centre, supporting routeing schemes for Magna Park and locating future HGV generating business development to the south of the town with good access to the M1, A4303 and A426. Harborough District Local Plan (Saved Policies) Policy EV/23 of the Harborough District Local Plan (HDC, 2007) states that, where appropriate, the Council will impose conditions on planning permission to ensure that development does not have an adverse effect on the character of its surroundings, or harm the amenities of nearby uses through air pollution. Air Quality Action Plan HDC has published a revised Air Quality Action Plan (HDC, 2013) which sets out the methodology for the assessment of traffic management and road layout modification schemes for which funding may be attainable. It notes that measures short-listed for inclusion within the emerging Action Plan will be considered for their suitability on highways grounds, and identifies a number of key aims. Assessment Criteria Health Criteria The Government has established a set of air quality standards and objectives to protect human health. The standards are set as concentrations below which effects are unlikely even in sensitive population groups, or below which risks to public health would be exceedingly small. They are based purely upon the scientific and medical evidence of the effects of an individual pollutant. The objectives set out the extent to which the Government expects the standards to be achieved by a certain date. They take account of economic efficiency, practicability, technical feasibility and timescale. The objectives for use by local authorities are prescribed within the Air Quality (England) Regulations, 2000, Statutory Instrument 928 (2000) and the Air Quality (England) (Amendment) Regulations 2002, Statutory Instrument 3043 (2002). Final Report June

4 Air Quality Assessment The objectives for nitrogen dioxide and PM 10 were to have been achieved by 2005 and 2004 respectively, and continue to apply in all future years thereafter. The PM 2.5 objective is to be achieved by Measurements across the UK have shown that the 1-hour nitrogen dioxide objective is unlikely to be exceeded where the annual mean concentration is below 60 µg/m 3 (Defra, 2009). Therefore, 1-hour nitrogen dioxide concentrations need only be considered if the annual mean concentration is above this level The objectives apply at locations where members of the public are likely to be regularly present and are likely to be exposed over the averaging period of the objective. Defra explains where these objectives will apply in its Local Air Quality Management Technical Guidance (Defra, 2009). The annual mean objectives for nitrogen dioxide and PM 10 are considered to apply at the façades of residential properties, schools, hospitals etc.; they do not apply at hotels. The 24-hour objective for PM 10 is considered to apply at the same locations as the annual mean objective, as well as in gardens of residential properties and at hotels. The 1-hour mean objective for nitrogen dioxide applies wherever members of the public might regularly spend 1-hour or more, including outdoor eating locations and pavements of busy shopping streets The European Union has also set limit values for nitrogen dioxide, PM 10 and PM 2.5. Achievement of these values is a national obligation rather than a local one (Directive 2008/50/EC of the European Parliament and of the Council, 2008). The limit values for nitrogen dioxide are the same levels as the UK objectives, but applied from 2010 (The Air Quality Standards Regulations (No. 1001), 2010). The limit values for PM 10 and PM 2.5 are also the same level as the UK statutory objectives, but applied from 2005 for PM 10 and will apply from 2015 for PM The relevant air quality criteria for this assessment are provided in Table Table 10.1 Air Quality Criteria for Nitrogen Dioxide, PM 10 and PM 2.5 Pollutant Time Period Objective Nitrogen Dioxide Fine Particles (PM 10 ) 1-hour Mean 200 µg/m 3 not to be exceeded more than 18 times a year Annual Mean 40 µg/m 3 24-hour Mean 50 µg/m 3 not to be exceeded more than 35 times a year Annual Mean 40 µg/m 3 Fine Particles a Annual Mean 25 µg/m3 (PM 2.5 ) a The PM 2.5 objective, which is to be met by 2020, is not in Regulations and there is no requirement for local authorities to meet it. Final Report June

5 Air Quality Assessment Construction Dust Criteria There are no formal assessment criteria for dust. In the absence of formal criteria, the approach developed by the Institute of Air Quality Management 1 (IAQM) (2014) has been used. Full details of this approach are provided in Appendix G1. Descriptors for Air Quality Impacts and Assessment of Significance Construction Dust Significance Guidance from the IAQM (IAQM, 2014) is that, with appropriate mitigation in place, the impacts of construction dust will not be significant. The assessment thus focuses on determining the appropriate level of mitigation so as to ensure that impacts will normally not be significant. Operational Significance There is no official guidance in the UK on how to describe air quality impacts, nor how to assess their significance. The approach developed by the IAQM (IAQM, 2009), and incorporated in Environmental Protection UK s (EPUK s) guidance document on planning and air quality (Environmental Protection UK, 2010), is therefore proposed. This approach includes elements of professional judgement It is important to differentiate between the terms impact and effect with respect to the assessment of air quality. The term impact is used to describe a change in pollutant concentration at a specific location. The term effect is used to describe an environmental response resulting from an impact, or series of impacts. Within this report, the air quality assessment has used published guidance and criteria described in the following sections to determine the likely air quality impacts at a number of sensitive locations. The potential significance of effects has then been determined by professional judgement, based on the frequency, duration and magnitude of predicted impacts and their relationship to appropriate air quality objectives. Assessment Method Consultation The assessment follows a methodology agreed with HDC via a telephone discussion between Gareth Rees (Air Quality Officer at HDC) and Stephen Moorcroft (Air Quality Consultants) held on 3 September It also takes into account all issues raised in the Council s Scoping Opinion. 1 The IAQM is the professional body for air quality practitioners in the UK. Final Report June

6 Air Quality Assessment Existing Conditions Existing sources of emissions within the study area have been defined using a number of approaches. A site visit has been carried out to identify existing sources from a visual inspection of the area. Industrial and waste management sources that may affect the area have been identified using Defra s Pollutant Release and Transfer Register (Defra, 2015b) and the Environment Agency s website what s in your backyard (Environment Agency, 2015). Local sources have also been identified through discussion with HDC s Regulatory Services, as well as through examination of the Council s Air Quality Review and Assessment reports Information on existing air quality has been obtained by collating the results of monitoring carried out by the local authority. This covers both the study area and nearby sites, the latter being used to provide context for the assessment. A 3-month monitoring survey (30 June 22 September 2014) has been undertaken at sites along the A5 and A4303; the results of this survey are included within the assessment. The location of these monitoring sites is shown in Figure The background concentrations across the study area have been defined using the national pollution maps published by Defra (Defra, 2015a). These cover the whole country on a 1x1 km grid. Current exceedences of the annual mean EU limit value for nitrogen dioxide have been identified using the maps of roadside concentrations published by Defra (2015c). These are the maps, currently based on 2012 data, used by the UK Government, together with the results from national AURN monitoring sites that operate to EU data quality standards, to report exceedences of the limit value to the EU. Road Traffic Impacts Sensitive Locations Concentrations of nitrogen dioxide, PM 10 and PM 2.5 have been predicted at a number of locations close to the proposed development. The receptors have been located on the façades of the properties closest to the road sources. Sixteen existing residential properties have been identified as receptors for the assessment. These locations are described in Table 10.2 and shown in Figure In addition, concentrations have been modelled at sites where diffusion tube monitoring has been carried out for this assessment, in order to verify the modelled results (see Appendix G4 for verification method). Final Report June

7 Air Quality Assessment Table 10.2 Description of Receptor Locations a Receptor Description 1 Residential property at Watling House, adjacent to the A5. 2 Residential property at Alma House, adjacent to the A5. 3 Residential property at Peach Tree Cottage, adjacent to the A5. 4 Residential property at Wibtoft Cottage, adjacent to the A5. 5 Residential property at White House Farm, adjacent to the A5. 6 Residential property at Emmanuel Cottages, adjacent to the A5. 7 Residential property at Wood Farm, adjacent to Coal Pit Lane. 8 Residential property at Walton Lodge Farm, adjacent to the B Residential property at 44 Lutterworth Road (B4027). 10 Residential property at 14 Lutterworth Road (B4027). 11 Residential property at 44 Coventry Road (B4027). 12 Residential property at Cross In Hand Farm, adjacent to the A5. 13 Residential property at Glebe Farm, adjacent to the A Residential property at Woodbrig House Farm, adjacent to the A Residential property at 56 Azalea Close, adjacent to Coventry Road. 16 Residential property at 11 Alexander Drive, near to the A4303. a Receptors modelled at a height of 1.5 m Final Report June

8 Air Quality Assessment Figure 10.1 Receptor Locations and Proposed Development Site Contains Ordnance Survey data Crown copyright and database right 2015 Assessment Scenarios Predictions of nitrogen dioxide, PM 10 and PM 2.5 concentrations have been carried out for a base year (2014), and the future years of 2016 and For 2016 and 2031, predictions have been made assuming both that the development does proceed (With Scheme), and does not proceed (Without Scheme). A further 2016 sensitivity test has been carried out for nitrogen dioxide that involves assuming no reduction in emission factors for road traffic from the baseline year. This is to address the issue identified by Defra (Carslaw, Beevers, Westmoreland, & Williams, 2011) that road traffic emissions have not been declining as expected (see later section on uncertainty). Nitrogen dioxide concentrations in 2016 with and without the scheme are thus presented for two scenarios: With Emissions Reduction and Without Emissions Reduction. Final Report June

9 Air Quality Assessment Modelling Methodology Concentrations have been predicted using the ADMS-Roads dispersion model. Details of the model inputs and the model verification are provided in Appendix G4, together with the method used to derive current and future year background nitrogen dioxide concentrations. Baseline Conditions Air Quality Management Areas In July 2006, HDC declared an Air Quality Management Area (AQMA) for exceedences of the annual mean nitrogen dioxide objective in Lutterworth town centre. The AQMA encompasses properties along the High Street in Lutterworth, extending from the junction with George Street to the north, to just below the junction with Stoney Hollow to the south Subsequent review and assessment reports confirmed the exceedence of the objective, and that an area to the south of the AQMA may also be exceeding the annual mean objective for nitrogen dioxide. The Further Assessment (HDC, 2012) has also identified that car and HGV traffic had the greatest impact on air quality in the AQMA, contributing over 80% of NOx emissions. While HGVs comprise only 6% of total movements, they were estimated to contribute over 40% of NOx Rugby Borough Council (RBC) has also declared an AQMA for exceedences of the annual mean objective for nitrogen dioxide. This area covers the whole urban area of Rugby, bounded by the southern boundary with Daventry District Council, the A5, M6, minor roads to the west of Long Lawford, A45 and M45. The RBC AQMA is approximately 5 km to the south of the application site and Lutterworth. Industrial sources A search of the UK Pollutant Release and Transfer Register (Defra, 2015b) and Environment Agency s what s in your backyard (Environment Agency, 2015) websites did not identify any significant industrial or waste management sources that are likely to affect receptors in the vicinity of the proposed development, in terms of air quality. Site Visit A site visit was carried out on 30 June Other than road traffic, no significant sources of air pollution were identified during the site visit. Air Quality Monitoring Monitoring Carried Out By Local Authorities HDC does not operate any automatic monitoring stations. There is a national network (AURN) station close to Market Harborough, but this is a rural site and unlikely to be representative of general air quality conditions in the study area. Final Report June

10 Air Quality Assessment HDC operates a network of passive nitrogen dioxide monitoring sites across the District. These include a number of sites in Lutterworth, both within and outside of the AQMA. There are additional sites in Walcote and Theddingworth, located on the A4304, approximately 1.7 and 12 km to the east of Lutterworth respectively. Annual mean nitrogen dioxide concentrations at roadside sites within the Lutterworth AQMA have consistently exceeded the objective, and there is little evidence of any downward trend in levels. Outside the AQMA, concentrations are below the objective. A summary of the measured concentrations over the period 2009 to 2013 is shown in Table Diffusion tube monitoring is also carried out by Hinckley & Bosworth Borough Council, including four sites located along the A5, to the west of the M69. A summary of the measured concentrations over the period 2009 to 2013 is also shown in Table 10.3; levels at both kerbside (1 m from the road) and building facade sites have all been well below the objective. Figure 10.2 HDC Monitoring Locations and Lutterworth AQMA Contains Ordnance Survey data Crown copyright and database right 2015 Final Report June

11 Air Quality Assessment Table 10.3 Summary of Annual Mean Nitrogen Dioxide (NO 2 ) Monitoring ( ) a b Site No. Site Type Location Harborough DC - Lutterworth 01n R Lutterworth Service Shop n R Maxwell Way n R Day Nursery n R Jazz Hair n R 77 Leicester Road n R 6 The Terrace, Rugby Road n/a n R 4-9 Regent Road n/a n R 26 Market Street n/a n R 24 Rugby Road n/a n R 17 Rugby Road n/a Harborough DC - Walcote 16n R Walcote Harborough DC - Theddingworth 28n R Spencerdene Main St n/a n/a n R Homeside Main St n/a n/a Hinckley & Bosworth BC 20 K Weldon A5 n/a n/a n/a 22 K Lester House A5 n/a n/a n/a 30 F Lester House (Façade) n/a F Weldon (Façade) n/a Notes K Kerbside Site R Roadside Site F Building Façade Site a b Exceedences of the objective level are shown in bold. Diffusion tube data for Harborough has been provided by HDC. Diffusion tube data for Hinckley and Bosworth have been taken from the 2013 Air Quality Progress Report (Hinckley & Bosworth BC, 2013). Monitoring Carried Out for IDI-G Three months of diffusion tube monitoring at six sites; three sites adjacent to the A5 and three sites near to the A4303 has been undertaken on behalf of IDI-G. At one of the sites next to the A4303 three diffusion tubes were collocated to test the consistency of the Final Report June

12 Air Quality Assessment diffusion tube measurements. These were prepared and analysed by Gradko International. The results, which have been bias adjusted and annualised, are summarised in Table 10.4 and the monitoring locations are shown in Figure The full diffusion tube results are presented in Appendix G8. Measured concentrations at these monitoring locations have been used to verify the model predictions, as set in Appendix G4. Monitoring location 3 has been excluded from the model verification, which is later discussed in paragraph 12 in Appendix G4. Figure 10.3 IDI-G Diffusion Tube Monitoring Locations Crown copyright and database rights License number Final Report June

13 Air Quality Assessment Table 10.4 Monitored Nitrogen Dioxide Concentrations (µg/m 3 ) Monitoring Location Location Annualised Concentration a 1 Alexander Drive, Near A A4303, Near TT Electronics 41.2 b 3 A4303, Near MPL 94.0 c 4 A5, Near White House Farm A5, Near Main Street A5, Near Green Lane 45.0 Objective 40 a b c Exceedences of the objective are shown in bold. This is based on the average of triplicate tubes each month during the monitoring period. One tube was lost/stolen and therefore monitoring only took place over 2-months; Further details are provided in Appendix G The measured annual mean nitrogen dioxide concentration exceeded the objective at two diffusion tube sites located alongside the A4303, where there is no relevant exposure. The objective is also exceeded at the diffusion tube site located at the kerbside of the A5 near to Green Lane, where there is relevant exposure (i.e. residential properties) nearby. Background Concentrations In addition to these locally measured concentrations, estimated background concentrations across the study area have been determined for 2014 and the future years of 2016 and 2031 (Table 10.5). In the case of nitrogen dioxide, two sets of 2016 backgrounds are presented to take into account uncertainty in future year vehicle emission factors. The derivation of background concentrations is described in Appendix G4. The background concentrations are all well below the objectives. Final Report June

14 Air Quality Assessment Table 10.5 Estimated Annual Mean Background Pollutant Concentrations in 2014, 2016 and 2031 (µg/m 3 ) Year NO 2 PM 10 PM a Without Reductions in Traffic Emissions b n/a n/a 2016 With Reductions in Traffic Emissions c With Reductions in Traffic Emissions d Objectives n/a = not applicable a This assumes that road vehicle emission factors in 2014 remain the same as in 2011 (See Appendix G4). b This assumes that road vehicle emission factors in 2016 remain the same as in c d This assumes that road vehicle emission factors reduce between 2014 and 2016 at the current official rates. This assumes that road vehicle emission factors reduce between 2014 and 2030 at the current official rates. The background concentrations in 2031 have been assumed to be the same as those for National Compliance There are no national network (AURN) monitoring sites within the study area where exceedences of the EU limit values have been identified. The national map of roadside annual mean concentrations identifies no exceedences (in 2012) of the limit value for nitrogen dioxide along the nearby sections M1, M6, A4303, A426 or A5. There are also no exceedences of the limit values for PM 10 or PM 2.5. Baseline Dispersion Model Results Baseline concentrations of nitrogen dioxide, PM 10 and PM 2.5 have been modelled at each of the existing receptor locations (see Table 10.2 and Figure 10.1). The results, which cover both the existing (2014) and future years (2016 and 2031) baselines (Without Scheme), are set out in Table 10.6, Table 10.7 and Table The future baseline for nitrogen dioxide covers the two scenarios: with the official reductions in vehicle emission factors and without these reductions. The modelled road components of nitrogen oxides concentrations have been adjusted by a factor of , which was derived during the model verification process, and the total NO 2 has been adjusted by a secondary verification factor of (see Appendix G4 for details of the model verification) Baseline The predicted annual mean concentrations of nitrogen dioxide are below the objective at all receptor locations, apart from at Receptor 1 (located alongside the A5 north of Magna Park) where concentrations are above the objective. All of the predictions for PM 10 and PM 2.5 are well below the objectives in Final Report June

15 Air Quality Assessment 2016 Baseline With Official Emission Reduction The predicted annual mean concentrations of nitrogen dioxide are below the objective at all receptor locations. All of the predictions for PM 10 and PM 2.5 are well below the objectives Baseline Without Emission Reduction The predicted annual mean concentrations of nitrogen dioxide are below the objective at all receptor locations, apart from at Receptors 1 and 2 (both are located alongside the A5 north of Magna Park) where concentrations are above the objective Baseline The predicted annual mean concentrations of nitrogen dioxide are below the objective at all receptor locations. All of the predictions for PM 10 and PM 2.5 are well below the objectives. Final Report June

16 Air Quality Assessment Table 10.6 Modelled Annual Mean Baseline Concentrations of Nitrogen Dioxide (µg/m 3 ) at Existing Receptors a Receptor Without Scheme 2031 Without Scheme d With Official Without Emissions Emissions Reduction b Reduction c Objective 40 a b Exceedences of the objective are shown in bold. This assumes that road vehicle emission factors reduce between 2014 and 2016 at the current official rates. c This assumes that road vehicle emission factors in 2016 remain the same as in d This assumes that road vehicle emission factors reduce between 2014 and 2031 at the current official rates. Final Report June

17 Air Quality Assessment Table 10.7 Modelled Baseline Concentrations of PM 10 at Existing Receptors Annual Mean (µg/m 3 ) No. Days >50 µg/m 3 Receptor Without Scheme 2031 Without Scheme Without Scheme 2031 Without Scheme Objective a The numbers of days with PM 10 concentrations greater than 50 µg/m 3 have been estimated from the relationship with the annual mean concentration described in LAQM.TG(09) (Defra, 2009). Final Report June

18 Air Quality Assessment Table 10.8 Modelled Baseline Annual Mean Concentrations of PM 2.5 at Existing Receptors (µg/m 3 ) Receptor Without Scheme 2031 Without Scheme Objective 25 Baseline Summary Baseline air quality conditions across the study area are generally good, and pollutant concentrations outside the Lutterworth AQMA are mostly below the objective. There are a couple of residential properties adjacent to the A5, near to Green Lane, where predicted concentrations of annual mean nitrogen dioxide are above the objective. These model predictions are consistent with measured concentrations in the area. Site Assets, Opportunities and Constraints The assets, opportunities and constraints are directly related to the potential for reducing or increasing traffic-generated pollution emissions. Assets The site provides good access to the strategic highway network, including the A5 and M1, and will not generate additional HGV traffic through areas of existing, poor air quality. Final Report June

19 Air Quality Assessment The main shift changes occur outside of traditional peak hours, and will further limit any non-hgv traffic and associated air quality impacts in Lutterworth. Opportunities The development of the Magna Park website will increase the opportunities for sustainable transport options (as described in Chapter 6: Traffic and Transport), thus minimising pollution emissions. Constraints There are no identified constraints to the proposed development. Construction Effects and Mitigation The construction works will give rise to a risk of dust impacts during demolition, earthworks and construction, as well as from trackout of dust and dirt by vehicles onto the public highway. Potential Impacts/Issues Potential Dust Emission Magnitude Demolition There will be a requirement to demolish Emmanuel and Lodge cottages with an approximate total volume of 600 m 3. Based on the example definitions set out in Table G1.1 in Appendix G1, the dust emission class for demolition is considered to be small. Earthworks The characteristics of the soil at the development site have been defined using the British Geological Survey s UK Soil Observatory website (British Geological Survey, 2015), as set out in Table Final Report June

20 Air Quality Assessment Table 10.9 Summary of Soil Characteristics Category Soil layer thickness Record Deep Grain Size (and Soil Parent Material) Mixed (Argillic a, Arenaceous b and Rudaceous c ) European Soil Bureau Description Soil Group Soil Texture Glacial Till, River Terrace Sand/Gravel, Riverine Clay, Floodplain Sands and Gravel All Loam d to Clayey Loam, Clay to Sandy Loam and Sand to Sandy Loam a b c d grain size < 0.06 mm. grain size mm. grain size > 2.0 mm. a loam is composed mostly of sand and silt Overall, it is considered that, when dry, this soil has the potential to be slightly dusty The site covers some 138,000 m 2 and most of this will be subject to earthworks. This will mainly involve the removal of topsoil and the excavation of sub soil which is usually damp and not prone to dust re-suspension. The earthworks are expected to last for a period of about 14-weeks. Dust will arise mainly from vehicles travelling over unpaved ground and from the handling of dusty materials. Based on the example definitions set out in Table G1.1 in Appendix G1, the dust emission class for earthworks is considered to be large. Construction Construction will involve the erection of a single building with a total building volume of around 2,070,000 m 3. The building will comprise primarily of a steel frame, which will not create any dust. Dust will arise from vehicles travelling over unpaved ground, the handling and storage of dusty materials. The construction works are expected to last for a period of 29-months. Based on the example definitions set out in Table G1.1 in Appendix G1, the dust emission class for construction is considered to be large. Trackout The number of vehicles accessing the site, which may track out dust and dirt will vary during the construction phase, but for the majority of the works there will be between about 100 to 200 outward heavy vehicle movements per day. Construction traffic will enter and exit via Mere Road off the A5. Based on the example definitions set out in Table G1.1 in Appendix G1, the dust emission class for trackout is considered to be large Table summarises the dust emission magnitude for the proposed development. Final Report June

21 Air Quality Assessment Table Summary of Dust Emission Magnitude Source Demolition Earthworks Construction Trackout Dust Emission Magnitude Small Large Large Large Sensitivity of the Area This assessment step combines the sensitivity of individual receptors to dust effects with the number of receptors in the area and their proximity to the site. It also considers additional site-specific factors such as topography and screening, and in the case of sensitivity to human health effects, baseline PM 10 concentrations. Sensitivity of the Area to Effects from Dust Soiling The IAQM guidance explains that residential properties and car parks are high sensitivity receptors to dust soiling, while commercial/industrial warehouses and agricultural fields are low sensitivity receptors (Table G1.2 in Appendix G1). The nearest residential property is within 100 m of the Site. The nearest sensitive receptors are 2 car parks within 20 m of the Site (see Figure 10.4). Using the matrix set out in Table G1.3 in Appendix G1, the area surrounding the onsite works is of medium sensitivity to dust soiling. Table shows that dust emission magnitude for trackout is large and Table G1.2 in Appendix G1 thus explains that there is a risk of material being tracked 500 m from the site exit. Since it is not known which roads construction vehicles will use beyond Mere Lane, it has been assumed that vehicles may travel both north and south along the A5. There are no residential properties or car parks within 50 m of the roads along which material could be tracked. There are, however, some agricultural fields within 20 m of the roads along which material could be tracked (see Figure 10.5), and Table G1.3 in Appendix G1 thus indicates that the area is of low sensitivity to dust soiling due to trackout (Table 10.11). Final Report June

22 Air Quality Assessment Figure 10.4 Distance Bands (Black) from the Site Boundary (Red) Contains Ordnance Survey data Crown copyright and database right 2015 Final Report June

23 Air Quality Assessment Figure 10.5 Distance Bands (Black) around Roads Used by Construction Traffic Within 500 m of the Site Boundary (Red) Contains Ordnance Survey data Crown copyright and database right 2015 Sensitivity of the Area to any Human Health Effects Residential properties are also classified as being of high sensitivity to human health effects. The matrix in Table G1.4 in Appendix G1 requires information on the baseline annual mean PM 10 concentration in the area. The maximum predicted baseline PM 10 Final Report June

24 Air Quality Assessment concentration at the receptors is 22.8 µg/m 3 (Table 10.7), and this value has been used. Using the matrix in Table G1.4 in Appendix G1, the area surrounding the onsite works and the area surrounding roads along which material may be tracked from the site are of low sensitivity to human health effects (Table 10.11). Sensitivity of the Area to any Ecological Effects The guidance considers SSSIs with dust-sensitive features to be of medium sensitivity. The nearest designated ecological site is the Misterton Marshes SSSI, which is located over 4 km away from the Site and will thus not be effected by the construction works. There are however, a number of agricultural fields within 20 m of the Site boundary and within 20 m along roads which material may be tracked, that may contain dust-sensitive features. These are considered to be of low sensitivity. Table G1.5 in Appendix G1 thus shows that the area is of low sensitivity to ecological effects (Table 10.11). Table Summary of the Area Sensitivity Effects Associated With: Sensitivity of the Surrounding Area On-site Works Trackout Dust Soiling Medium Sensitivity Low Sensitivity Human Health Low Sensitivity Low Sensitivity Ecological Low Sensitivity Low Sensitivity Significance of Predicted Effects The dust emission magnitudes in Table have been combined with the sensitivities of the area in Table using the matrix in Table G1.6 in Appendix G1, in order to assign a risk category to each activity. The resulting risk categories for the four construction activities, without mitigation, are set out in Table These risk categories have been used to determine the appropriate level of mitigation as set out in paragraph Table Summary of Risk of Impacts Without Mitigation Source Dust Soiling Human Health Ecology Demolition Low Risk Negligible Negligible Earthworks Medium Risk Low Risk Low Risk Construction Medium Risk Low Risk Low Risk Trackout Low Risk Low Risk Low Risk The IAQM does not provide a method for assessing the significance of effects before mitigation, and advises that pre-mitigation significance should not be determined. With Final Report June

25 Air Quality Assessment appropriate mitigation in place, the IAQM guidance is clear that the residual effect will normally not be significant (IAQM, 2014). Proposed Mitigation Measures to mitigate dust emissions will be required during the construction phase of the development in order to reduce impacts upon nearby sensitive receptors The Site has been identified as a Medium Risk site during earthworks and construction for dust soiling effects, and as a Low Risk site during demolition and trackout for dust soiling effects. For human health and ecology effects, the Site has been identified as a Low Risk site during earthworks, construction and trackout, and as a Negligble Risk site during demolition, as set out in Table Comprehensive guidance has been published by IAQM (IAQM, 2014) that describes measures that should be employed, as appropriate, to reduce the impact of a low and medium risk site, along with guidance on monitoring during demolition and construction (Institute of Air Quality Management, 2012b). This reflects best practice experience and has been used, together with the professional experience of the consultant and the findings of the dust impact assessment, to draw up a set of measures that should be incorporated into the specification for the works. These measures are described in Appendix G The mitigation measures should be written into a dust management plan (DMP). The DMP may be integrated into a Code of Construction Practice or the Construction Environmental Management Plan, and may require monitoring Where mitigation measures rely on water, it is expected that only sufficient water will be applied to damp down the material. There should not be any excess to potentially contaminate local watercourses. Operational Effects and Mitigation Potential Impacts/Issues Predicted annual mean concentrations of nitrogen dioxide, PM 10 and PM 2.5, as well as days with PM 10 >50 µg/m 3, are set out in Table 10.13, Table 10.14, Table and Table for both the Without Scheme and With Scheme scenarios, for both 2016 and These tables also describe the impacts at each receptor using the impact descriptors given in Appendix GA2. For nitrogen dioxide, results are presented for two scenarios in 2016 to reflect current uncertainty in Defra s future-year vehicle emission factors. Nitrogen Dioxide With Official Emissions Reduction In 2016, the annual mean nitrogen dioxide concentrations are predicted to be below the objective at all receptors, with and without the proposed development. The magnitudes of change range between imperceptible to small. The impacts are negligible at most receptors, but slight adverse at Receptor 1. In 2031, annual mean concentrations of nitrogen dioxide are well below the objective, with or without the proposed development. Final Report June

26 Air Quality Assessment Nitrogen Dioxide Without Emissions Reduction 2016 Only Assuming no reduction in emissions, the annual mean nitrogen dioxide concentrations are below the objective at all receptors in 2016, apart from at Receptors 1 and 2 with and without the proposed development. These receptors are at locations where concentrations have been measured above the objective level in The magnitudes of change range between imperceptible to small. The impacts are negligible at most receptors, but slight adverse at Receptors 1, 2 and 4. PM 10 and PM The annual mean PM 10 and PM 2.5 concentrations in both 2016 and 2031 are well below the objectives at all receptors, with or without the scheme, as are the numbers of days with PM 10 concentrations above 50 µg/m The magnitudes of change are imperceptible at all receptors. Coupled with the concentrations all being well below the objective, the impacts are thus described as negligible. Final Report June

27 Air Quality Assessment Table Predicted Impacts on Annual Mean Nitrogen Dioxide Concentrations (µg/m 3 ) a Receptor With Official Emissions Reduction b Without Emissions Reduction c With Official Emissions Reduction d Without Scheme With Scheme Impact Descriptor Without Scheme With Scheme Impact Descriptor Without Scheme With Scheme Impact Descriptor Slight Adverse Slight Adverse Negligible Negligible Slight Adverse Negligible Negligible Negligible Negligible Negligible Slight Adverse Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Objective a b Exceedences of the objective as shown in bold. This assumes that road vehicle emission factors reduce between 2014 and 2016 at the current official rates. c This assumes that road vehicle emission factors in 2016 remain the same as in d This assumes that road vehicle emission factors reduce between 2014 and 2031 at the current official rates. Final Report June

28 Air Quality Assessment Table Predicted Annual Mean PM 10 Impacts (µg/m 3 ) Receptor Without Scheme With Scheme Impact Descriptor Without Scheme With Scheme Impact Descriptor Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Objective Final Report June

29 Air Quality Assessment Table Predicted Impacts of Days With PM 10 Concentrations > 50 µg/m 3 a Receptor Without Scheme With Scheme Impact Descriptor Without Scheme With Scheme Impact Descriptor Negligible 5 5 Negligible Negligible 4 4 Negligible Negligible 3 3 Negligible Negligible 4 4 Negligible Negligible 2 2 Negligible Negligible 2 2 Negligible Negligible 1 1 Negligible Negligible 0 0 Negligible Negligible 1 1 Negligible Negligible 1 1 Negligible Negligible 1 1 Negligible Negligible 2 2 Negligible Negligible 1 1 Negligible Negligible 1 1 Negligible Negligible 1 1 Negligible Negligible 1 1 Negligible Objective a The numbers of days with PM 10 concentrations greater than 50 µg/m 3 have been estimated from the relationship with the annual mean concentration described in LAQM.TG(09) (Defra, 2009). Final Report June

30 Air Quality Assessment Table Predicted Annual Mean PM 2.5 Impacts (µg/m 3 ) Receptor Without Scheme With Scheme Impact Descriptor Without Scheme With Scheme Impact Descriptor Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Negligible Objective Uncertainty in Road Traffic Modelling Predictions There are many components that contribute to the uncertainty of modelling predictions. The model used in this assessment is dependent upon the traffic data that have been input, which will have inherent uncertainties associated with them. There are then additional uncertainties, as the model is required to simplify real-world conditions into a series of algorithms. An important stage in the process is model verification, which involves comparing the model output with measured concentrations (see Appendix G4). Because the model has been verified and adjusted, there can be reasonable confidence in the prediction of current year (2014) concentrations Predicting pollutant concentrations in a future year will always be subject to greater uncertainty. For obvious reasons, the model cannot be verified in the future, and it is necessary to rely on a series of projections provided by DfT and Defra as to what will happen to traffic volumes, background pollutant concentrations, and vehicle emissions. A disparity between the road transport emission projections and measured annual mean Final Report June