ENVIRONMENTAL STATEMENT ADDENDUM Air Quality STAMBRIDGE MILLS ENVIRONMENTAL STATEMENT ADDENDUM OCTOBER 2010 PLANNING APPLICATION REFERENCE

Transcription

1 STAMBRIDGE MILLS ENVIRONMENTAL STATEMENT ADDENDUM OCTOBER 2010 PLANNING APPLICATION REFERENCE 11/00494/FUL An Environmental Statement was submitted to Rochford District Council (RDC) in August 2011 accompanying a planning application concerning land at Stambridge Mills, Rochford. Following this submission, the ES was circulated to both statutory and non-statutory consultees during the determination period for comment upon environmental information. Following the submission a comment has been received from RDC Environmental Health Officer. To address these comments, the applicant has commissioned additional further air quality assessment work which is presented within this ES Addendum. No amendments to the ES have been made apart from revisions to Chapter 7: of the ES.

2 7 AIR QUALITY 7.1 Introduction This chapter describes the potential air quality impacts associated with the proposed residential development at the Stambridge Mills site, Rochford. The assessment has been carried out by Consultants Ltd on behalf of the Inner London Group The proposed development site lies approximately 1 km to the east of Rochford town centre. It is bounded by agricultural land to the north and west, Broomhills Care Centre to the east, and to the south by the River Roach. Beyond the River Roach lies Purdeys Industrial Estate The proposed development will comprise up to 96 residential units, including 45 houses and 51 apartments. Rochford District Council has not declared any Management Areas (AQMAs) in close proximity to the site, however it has concerns regarding concentrations of nitrogen dioxide within Rochford town centre, which are currently being investigated with additional monitoring. The development would lead to an increase in traffic on the local roads, which may impact on air quality at existing residential properties. The new residential properties will also be subject to the impact of road traffic emissions from the adjacent road network. 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 demolition and construction activities to impact upon both existing and new properties. The main pollutants of concern related to construction activities are dust and PM This chapter describes existing local air quality conditions, and predicted air quality in the future assuming that the proposed development does, or does not proceed. The assessment of traffic-related impacts focuses on 2012, which is the earliest anticipated year of opening. The assessment of construction dust impacts focuses on the anticipated duration of the works This assessment has been prepared taking into account all relevant local and national guidance and regulations, and follows a methodology agreed with Rochford District Council. 7.2 Assessment Approach Methodology Existing Conditions Existing sources of emission 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, 2011a). Local sources have also been identified through discussion with Rochford District Council s Environmental Health team, 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 within Rochford. The background concentrations across the study area have been defined using the national pollution maps published by Defra (Defra, 2011b). These cover the whole country on a 1x1 km grid. Road Traffic Impacts Sensitive Locations Concentrations of nitrogen dioxide, PM 10 and PM 2.5 have been predicted at a number of worst-case locations both within, and close to, the proposed development. Receptors have been selected to represent these worst-case locations. Relevant sensitive locations are places where members of the

3 public might be expected to be regularly present over the averaging period of the objectives. For the annual mean and daily mean objectives that are the focus of this assessment, sensitive receptors will generally be residential properties, schools, nursing homes, etc.. When selecting these receptors, particular attention has been given to assessing impacts close to junctions, where traffic may become congested, and where there is a combined effect of several road links Twenty-two existing residential properties have been identified as receptors for the assessment. An additional six receptor locations have been identified within the new development, which represents the worst-case exposure to existing sources. These locations are described in Table A7.1 (Appendix 7.1), and shown in Figures In addition, concentrations have been modelled at the six diffusion tube monitoring sites within Rochford (Figure 7.5) in order to verify the modelled results (see Appendix 7.2 for verification method). Impact Predictions Predictions of nitrogen dioxide, PM 10 and PM 2.5 concentrations have been carried out for a base year (2010), and the proposed year of opening (2012). For 2012, predictions have been made assuming both that the development does proceed (With Scheme), and does not proceed (Without Scheme) The potential cumulative impacts associated with the Stambridge Mills, Brays Lane, Hall Road and Rectory Road, South Hawkwell committed developments have been fully considered by including the cumulative traffic flows into the 2012 Baseline assessment Predictions have been carried out using the ADMS-Roads dispersion model (v3). The model requires the user to provide various input data, including the Annual Average Daily Traffic (AADT) flow, the proportion of heavy duty vehicles (HDVs), road characteristics (including road width and street canyon height, where applicable), and the vehicle speed. Vehicle emissions are calculated within ADMS-Roads (v3) using this information and emission factors from the Emission Factor Toolkit (EFT, Version 4.2.2) published by Defra (Defra, 2011b). It is also necessary to input background pollutant concentrations. These have been derived from the national maps discussed in the section on Existing Conditions The emission factors within the EFT are year-specific, such that they include projections of how newer vehicles will enter the fleet; newer vehicles are expected to emit less pollution as they conform to increasingly stringent Euro standards. Recently, however, a disparity between these official emission projections and measured concentrations of nitrogen oxides and nitrogen dioxide has been identified and there is concern that concentrations may not decline as rapidly in the future as projected by the emission factors. At this stage Defra has advised that where existing forecasting information is used, account should be taken of the performance of different vehicle types and of the Euro standards overall. This study is based on a worst-case assumption for predictions of nitrogen dioxide concentrations in which the emission factors and background concentrations for the future assessment year (2012) have been assumed to remain unchanged from the year of model verification (2010). This is further discussed in the Limitations section (paragraph ) The model has been run using the most recent full year of meteorological data (2010) from the monitoring station located at Southend Airport, which is approximately 2 km south-west of the Stambridge Mills site, and is considered suitable for this area AADT flows, and the proportions of HDVs for each scenario have been provided by Steer Davies Gleave, the applicant s transport consultants for these proposals, for each of the assessment scenarios. Traffic speeds have been estimated from local speed restrictions and take account of the proximity to a junction. Traffic data used in this assessment are summarised in Table 7.1.

4 Table 7.1: Summary of Traffic Data used in the Assessment a Road Link 2010 Baseline 2012 Baseline 2012 With Scheme West St 2,138 (4.5%) 2,183 (4.2%) 2,183 (4.2%) North St 5,623 (1.0%) 5,746 (1.1%) 6,013 (1.1%) East St 4,465 (3.0%) 4,554 (3.1%) 4,733 (3.1%) South St 8,151 (2.0%) 8,318 (2.1%) 8,697 (2.1%) Southend Road N of Sutton Rd 23,373 (3.5%) 26,190 (3.2%) 26,513 (3.3%) Sutton Road 17,883 (3.6%) 18,852 (3.9%) 18,852 (3.9%) Southend Road S of Sutton Rd 16,113 (4.0%) 18,237 (4.0%) 18,596 (4.0%) Stambridge Rd W of Mill Lane 2,717 (4.0%) 2,773 (3.9%) 3,263 (3.9%) Mill Lane 256 (4.5%) 290 (4.8%) 802 (4.9%) Stambridge Rd E of Mill Lane 2,528 (3.6%) 2,583 (3.6%) 2,617 (3.6%) a Values in parentheses are proportions of HDVs. Construction Impacts Locations sensitive to dust emitted during construction will be places where members of the public are regularly present. Residential properties and commercial operations close to the site will be most sensitive to construction dust. Any areas of sensitive vegetation or ecology that are very close to dust sources may also be susceptible to some negative effects It is very difficult to quantify emissions of dust from construction activities. It is thus common practice to provide a qualitative assessment of potential impacts, making reference to the assessment criteria set out in Table 7.4 and Table 7.5. 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 Regulations 2000 (Stationery Office, 2000) and the (England) (Amendment) Regulations 2002 (Stationery Office, 2002). The relevant objectives for this assessment are provided in Table 7.2.

5 Table 7.2: Objectives for Nitrogen Dioxide and PM 10 Pollutant Time Period Objective Nitrogen Dioxide 1-hour mean 200 g/m 3 not to be exceeded more than 18 times a year Annual mean 40 g/m 3 Fine Particles 24-hour mean 50 g/m 3 not to be exceeded more than 35 times a year (PM 10 ) a Annual mean 40 g/m 3 a Measured by the gravimetric method 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. 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 g/m 3 (Defra, 2009). Therefore, 1-hour nitrogen dioxide concentrations will only be considered if the annual mean concentration is above this level The European Union has also set limit values for both nitrogen dioxide and PM 10. Achievement of these values is a national obligation rather than a local one. The limit values for nitrogen dioxide are the same levels as the UK objectives, and are to be achieved by 2010 (Stationery Office, 2007). The limit values for PM 10 are also the same level as the UK statutory objectives, and were to be achieved by More recently, new health criteria have been introduced for PM 2.5 and these are shown summarised in Table 7.3. The 2007 Strategy (Defra, 2007) sets out both an exposurereduction approach and a backstop annual mean objective for PM 2.5. The former is an objective focused on reducing average exposures across the most heavily populated areas of the country, and is not directly applicable to individual schemes. It is supported by the backstop objective or concentration cap to ensure a minimum environmental standard. These PM 2.5 objectives have not been included in Regulations A new air quality directive (2008/50/EC) was adopted in May 2008, and includes a national exposure reduction target, a target value and a limit value for PM 2.5. The UK Government transposed this new directive into national legislation in June 2010 (Stationery Office, 2010).

6 Table 7.3: Relevant Criteria for PM 2.5 Time Period Objective/Obligation To be achieved by UK objectives Annual mean 25 µg/m year running annual mean 15% reduction in concentrations measured at urban background sites Between 2010 and 2020 Annual mean Target value of 25 µg/m Annual mean Limit value of 25 µg/m European obligations Annual mean 3 year Average Exposure Indicator (AEI) a 3 year Average Exposure Indicator (AEI) Stage 2 indicative Limit value of 20 µg/m Exposure reduction target relative to the AEI depending on the 2010 value of the 3 year AEI (ranging from a 0% to a 20% reduction) 2020 Exposure concentration obligation of 20 µg/m a The 3 year running annual mean or AEI is calculated from the PM 2.5 concentration averaged across all urban background monitoring locations in the UK e.g. the AEI for 2010 is the mean concentration measured over 2008, 2009 and Construction Dust Criteria There are no formal assessment criteria for dust. In the absence of formal criteria, a set of distance based criteria has been developed (Table 7.4). These criteria are based on the professional experience of the consultants, drawn from many years of involvement with assessments of different types of project, together with discussions with practitioners in the field, and consideration of a range of published reports. Table 7.4: Assessment Criteria for Dust from Construction Activities, with Standard Mitigation in Place Source Scale Description Soiling PM 10 a Potential Distance for Significant Effects (Distance from source) Vegetation effects Major Moderate Minor Large construction sites, with high use of haul routes Moderate sized construction sites, with moderate use of haul routes Minor construction sites, with limited use of haul routes 100 m 25 m 25 m 50 m 15 m 15 m 25 m 10 m 10 m a Significance based on the 2004 objective, which allows 35 daily exceedences/year of 50 g/m There is also the possibility of dust being tracked out of the site along roads. Table 7.5 sets out the assessment criteria in terms of distance from the site to which significant dust may be tracked out and the potential distance from the roadside for significant effects.

7 Table 7.5: Assessment Criteria for Construction Dust Track-Out with Standard Mitigation in Place Scale Source Distance along roadways that dust might be tracked Potential Distance from roadways for Significant Effects (Distance from edge of road) Soiling PM 10 Vegetation effects Major 250 m 50 m 15 m 15 m Moderate 100 m 25 m 10 m 10 m Minor 25 m 15 m 5 m 5 m The scale of the development with respect to the assessment of construction dust has been determined using the best practice guidance for the control of dust from construction and demolition, published by the Greater London Authorities in 2006 (GLA, 2006). The guidance categorises construction sites as Low, Medium or High risk in relation to dust generation based on criteria outlined in Table 7.6, below. The guidance has been designed for construction sites in Greater London, but may still be usefully applied to the assessment of construction dust at sites outside of Greater London. Table 7.6: GLA (2006) Site Evaluation Guidelines Category Low Risk Sites Medium Risk Sites High Risk Sites Description Developments of up to 1,000 m 2 of land and; Developments of 1 to 10 properties and; Potential for emissions and dust to have an infrequent impact on sensitive receptors. Developments of between 1,000 m 2 and 15,000 m 2 of land and; Developments of 10 to 150 properties and; Potential for emissions and dust to have an intermittent or likely impact on sensitive receptors. Developments of over 15,000 m 2 ; Developments of over 150 properties or; Major developments referred to the Mayor and/or the London Development Agency, or; Major Development defined by the London borough or; Potential for emissions and dust to have a significant impact on sensitive receptors. Descriptors for Impacts and Assessment of Significance There is no official guidance in the UK on how to describe the nature of air quality impacts nor to assess their significance. The approach developed by the Institute of Management 1 (IAQM, 2009), and incorporated in Environmental Protection UK s guidance document on planning and air quality (EPUK, 2010), has therefore been used. This involves three distinct stages: the application of descriptors for magnitude of change; the description of the impact at each sensitive receptor; and then the assessment of overall significance of the scheme The definition of impact magnitude is solely related to the degree of change in pollutant concentrations, expressed in microgrammes per cubic metre, but originally determined as a percentage of the air quality objective. Impact description takes account of the impact magnitude and of the absolute 1 The IAQM is the professional body for air quality practitioners in the UK.

8 concentrations and how they relate to the air quality objectives or other relevant standards. The descriptors for the magnitude of change due to the scheme are set out in Table 7.7, while Tables 7.8 and 7.9 set out the impact descriptors. These tables have been designed to assist with describing air quality impacts at each specific receptor. They apply to the pollutants relevant to this scheme and the objectives against which they are being assessed. Table 7.7: Definition of Impact Magnitude for Changes in Ambient Pollutant Concentrations Magnitude of Change Annual Mean NO 2 /PM 10 No. days with PM 10 concentration greater than 50 µg/m 3 Annual Mean PM 2.5 Large Increase/decrease 4 µg/m 3 Increase/decrease >4 days Increase/decrease 2.5 µg/m 3 Medium Small Imperceptible Increase/decrease 2 - <4 µg/m 3 Increase/decrease 2-4 days Increase/decrease <2 µg/m 3 Increase/decrease 1-2 days Increase/decrease <0.4 µg/m 3 Increase/decrease <1 day Increase/decrease µg/m 3 Increase/decrease <1.25 µg/m 3 Increase/decrease <0.25 µg/m 3 Table 7.8: Impact Descriptors for Changes to Annual Mean Nitrogen Dioxide, PM 10 and PM 2.5 Concentrations at a Receptor Absolute Concentration in Relation to Objective/Limit Value Change in Concentration a Small Medium Large Increase with Scheme Above Objective/Limit Value With Scheme ( 40 g/m 3 of NO 2 or PM 10 ) ( 25 µg/m 3 of PM 2.5 ) Slight Adverse Moderate Adverse Substantial Adverse Just Below Objective/Limit Value With Scheme (36-<40 g/m 3 of NO 2 or PM 10 ) ( <25 µg/m 3 of PM 2.5 ) Slight Adverse Moderate Adverse Moderate Adverse Below Objective/Limit Value With Scheme (30-<36 g/m 3 of NO 2 or PM 10 ) (18.75-<22.5 g/m 3 of PM 2.5 ) Negligible Slight Adverse Slight Adverse Well Below Objective/Limit Value With Scheme (<30 g/m 3 of NO 2 or PM 10 ) (<18.75 g/m 3 of PM 2.5 ) Negligible Negligible Slight Adverse Decrease with Scheme Above Objective/Limit Value Without Scheme ( 40 g/m 3 of NO 2 or PM 10 ) ( 25 g/m 3 of PM 2.5 ) Slight Beneficial Moderate Beneficial Substantial Beneficial Just Below Objective/Limit Value Without Scheme (36-<40 g/m 3 of NO 2 or PM 10 ) (22.5-<25 g/m 3 of PM 2.5 ) Slight Beneficial Moderate Beneficial Moderate Beneficial Below Objective/Limit Value Without Scheme (30-<36 g/m 3 of NO 2 or PM 10 ) Negligible Slight Beneficial Slight Beneficial

9 (18.75-<22.5 g/m 3 of PM 2.5 ) Well Below Objective/Limit Value Without Scheme (<30 g/m 3 of NO 2 or PM 10 ) (<18.75 g/m 3 of PM 2.5 ) Negligible Negligible Slight Beneficial a Where the Impact Magnitude is Imperceptible, then the Impact Description is Negligible. Table 7.9: Impact Descriptors for Changes to Number of Days with PM 10 Concentration Greater than 50 µg/m 3 at a Receptor Absolute Concentration in Relation to Objective/Limit Value Change in Concentration a Small Medium Large Increase with Scheme Above Objective/Limit Value With Scheme (>35 days) Slight Adverse Moderate Adverse Substantial Adverse Just Below Objective/Limit Value With Scheme (32-35 days) Slight Adverse Moderate Adverse Moderate Adverse Below Objective/Limit Value With Scheme (26-32 days) Negligible Slight Adverse Slight Adverse Well Below Objective/Limit Value With Scheme (<26 days) Negligible Negligible Slight Adverse Decrease with Scheme Above Objective/Limit Value Without Scheme (>35 days) Slight Beneficial Moderate Beneficial Substantial Beneficial Just Below Objective/Limit Value Without Scheme (32-35 days) Slight Beneficial Moderate Beneficial Moderate Beneficial Below Objective/Limit Value Without Scheme (26-32 days) Negligible Slight Beneficial Slight Beneficial Well Below Objective/Limit Value Without Scheme (<26 days) Negligible Negligible Slight Beneficial a Where the Impact Magnitude is Imperceptible, then the Impact Description is Negligible The IAQM guidance is that the assessment of significance should be based on professional judgement, with the overall air quality impact of the scheme described as either, insignificant, minor, moderate or major. In drawing these conclusions, the factors set out in Table 7.10 should be taken into account.

10 Table 7.10: Factors Taken into Account in Determining Significance Factors Number of people affected by increases and/or decreases in concentrations and a judgement on the overall balance. The number of people exposed to levels above the objective or limit value, where new exposure is being introduced. The magnitude of the changes and the descriptions of the impacts at the receptors i.e. using the findings based on Tables 7.7, 7.8 and 7.9. Whether or not an exceedence of an objective or limit value is predicted to arise in the study area where none existed before or an exceedence area is substantially increased. Whether or not the study area exceeds an objective or limit value and this exceedence is removed or the exceedence area is reduced. Uncertainty, including the extent to which worst-case assumptions have been made The extent to which an objective or limit value is exceeded, e.g. an annual mean NO 2 of 41 g/m 3 should attract less significance than an annual mean of 51 g/m 3 Policy Context Strategy The Strategy (Defra, 2007) provides the policy framework 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 important role. The strategy describes the Local 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 Management Area (AQMA), and prepare an action plan which identifies appropriate measures that will be introduced in pursuit of the objectives. Planning Policy National policy on air quality and planning is set out in Planning Policy Statement 23 (PPS23) (ODPM, 2004). This contains advice on when air quality should be a material consideration in development control decisions. Existing, and likely future, air quality should be taken into account, as well as the presence of any AQMAs. PPS23 notes that the findings of local authority air quality reviews and assessments will be important, as they will identify local air pollution problems, which may in turn influence the siting of certain types of development. The need for compliance with any statutory environmental quality standards or objectives, including the air quality objectives prescribed by the Air Quality Regulations 2000 (Stationery Office, 2000) and Amending Regulations 2002 (Stationery Office, 2002), will also be a factor in determining whether air quality is a material consideration Further emphasis is given to the importance of air quality objectives and AQMAs in the Appendices to PPS23. The impact of a development on air quality is likely to be particularly important: where the development is proposed inside, or adjacent to an AQMA; where the development could in itself result in the designation of an AQMA; and where to grant planning permission would conflict with, or render unworkable, elements of a Local Authority s air quality action plan.

11 PPS23 states clearly that not all planning applications for developments inside or adjacent to AQMAs should be refused, even if the development would result in a deterioration of local air quality, as such an approach could sterilise development. Regional Policies On 6th July 2010, the Secretary of State for Communities and Local Government revoked Regional Strategies with immediate effect. In the longer term the legal basis for Regional Strategies will be abolished through the Localism Bill and new ways for local authorities to address strategic planning and infrastructure issues based on cooperation will be introduced. The impact of this change on local planning processes is still unknown. For completeness, the relevant policies from the East of England Plan (Stationery Office, 2008) are discussed below. There are no specific policies relating to air quality, however a number, relating to traffic management and environmental protection, include reference to the impact of development, and in particulr development-related traffic, on pollution, Policy ENV7: Quality in the Built Environment, states that: Local Policies New development should..reduce pollution, including emissions, noise and light pollution The Rochford District Replacement Local Plan was adopted in June 2006 (Rochford DC, 2006), however, neither of the policies relating to pollution and air quality (PN1 and PN4) were adopted beyond June Recent changes to the planning legislation require the Council to replace the Local Plan with a Local Development Framework (LDF) (Rochford DC, 2009a). This portfolio of planning documents, individually known as Local Development Documents, will deliver the spatial development strategy for Rochford and build upon existing local and regional strategies and initiatives. The Council is currently in the process of preparing the Core Strategy The Core Strategy Submission Document (Rochford DC, 2009b) recently submitted to the Secretary of State for independent examination contains Policy ENV5 which states: Limitations New residential development will be restricted in Management Areas in order to reduce public exposure to poor air quality. In areas where poor air quality threatens to undermine public health and quality of life, the Council will seek to reduce the impact of poor air quality on receptors in that area and to address the cause of the poor air quality. Proposed development will be required to include measures to ensure it does not have an adverse impact on air quality There are many components that contribute to the uncertainty of modelling predictions. The model used in this assessment is dependant 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 7.2). Because the model has been verified and adjusted, there can be reasonable confidence in the prediction of Baseline (2010) 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 as to what will happen to background pollutant concentrations, and to vehicle emissions Recently however, a disparity between the road transport emission projections and measured annual mean concentrations of nitrogen oxides and nitrogen dioxide has been identified by Defra (Carslaw et al, 2011). This applies across the UK, although there is considerable inter-site variation.

12 Whilst the emission projections suggest that both annual mean nitrogen oxides and nitrogen dioxide concentrations should have fallen by around 15-25% over the past 6 to 8 years, at many monitoring sites levels have remained relatively stable, or have even shown a slight increase The precise reason for this disparity is not known, but is thought to be related to the actual on-road performance of diesel vehicles when compared to the calculations based on the Euro standards. It may therefore be expected that nitrogen oxides and nitrogen dioxide concentrations will not fall as quickly in future years as the current projections indicate. However, at this stage, there is no robust evidence upon which to carry out any revised predictions In light of these findings, the assessment of air quality impacts of the proposed development, and the cumulative impact of other committed developments, has been carried out for 2012 traffic flows, but using vehicle emission factors and background concentrations that remain unchanged from This represents a worst-case approach which is likely to have over-estimated the nitrogen dioxide concentrations in This should be borne in mind when considering the conclusions of this assessment. 7.3 Baseline Conditions Site Description and Context The proposed development site lies approximately 1 km to the east of Rochford town centre. It is bounded by agricultural land to the north and west, Broomhills Care Centre to the east, and to the south by the River Roach. Beyond the River Roach lies Purdeys Industrial Estate. Baseline Survey Information Outcomes of Review and Assessment Rochford District Council has investigated air quality within its area as part of its responsibilities under the Local Management (LAQM) regime. On the 27th January 2010, an AQMA was declared in the vicinity of Rawreth Industrial Estate in Rayleigh for PM 10. Rayleigh lies approximately 8 km to the west of the application site, and the AQMA has no significant bearing on the proposed development. Industrial Sources A search of the UK Pollutant Release and Transfer Register website (Defra, 2011a) did not identify any industrial or waste management sources within 1 km of the proposed development. The Purdeys Industrial Estate lies to the south of the proposed development site, on the opposite site of the River Roach. The industrial estate is occupied by a number of commercial and light industrial facilities. During the site visit, two operations which are potential sources of dust emissions were identified. These are JKS Aggregates at the west end of Purdeys Way and an unidentified operation to the northeast of Welton Way (possibly associated with the adjacent Eco Logic Recycling). These activities are located some distance (at least 200 m) from the southern boundary of the proposed development. They are considered to represent a low risk to the proposed development site. Aircraft Emissions London Southend Airport lies over 1.2 km to the south west of the proposed application site. The impact of aircraft emissions on residents of the proposed development has not been assessed on the basis of criteria published in LAQM.TG(09). This guidance confirms that emissions of PM 10 from airports are insignificant, and that significant impacts associated with nitrogen dioxide are only likely to occur in the vicinity of airports with an annual throughput of passengers in excess of 10 million passengers per annum, or where the NOx background concentration is greater than 25 µg/m 3. The NOx mapped background concentration at Southend Airport in 2012 is 24.9 µg/m 3 (Defra, 2011b), which is below the criterion. In January 2010, Southend-on-Sea Borough Council Development Control Committee resolved to approve Planning Permission for a runway extension that would allow the airport to grow to just under 2 million passengers in This remains below the criterion in the guidance.

13 Monitoring Data Rochford District Council operates six roadside diffusion tubes within Rochford (tubes supplied and analysed by Environmental Scientific Groups, using the 50% TEA in acetone method). Data are presented in Table Measured concentrations are below the annual mean nitrogen dioxide objective in 2010 at all but one of the sites. Table 7.11: Summary of Nitrogen Dioxide (NO 2 ) Diffusion Tube Monitoring (2010) a Site ID Location Annual Mean (µg/m 3 ) WS West St 24.7 NS North St 25.5 ES East St 29.4 SS South St 37.1 SR Southend Road 34.2 ABSR Anne Boleyn Sutton Road 40.3 Objective 40 a All data have been bias adjusted by Rochford District Council using a local co-location study. The bias correction factor for 2010 is 0.75 (Rochford District Council, 2011) There are no automatic monitoring sites within the Rochford District Council area. PM 10 concentrations measured at the Thurrock urban background automatic monitoring station, operated as part of the Automatic Urban and Rural Network (AURN), are therefore summarised in Table Concentrations were well below the relevant objectives and limit values in Table 7.12: Summary of PM 10 Monitoring (2010) FDMS Analyser a Site PM 10 Annual Mean (µg/m 3 ) No. Days >50 µg/m 3 Thurrock AURN a Objectives PM 10 measured using FDMS In addition to these locally measured concentrations, estimated background concentrations in the study area have been obtained from the national maps (Table 7.13). The background pollutant concentrations displayed in Table 7.13 are for 2010; as stated earlier these are assumed to remain unchanged by Table 7.13: Estimated Annual Mean Background Pollutant Concentrations in 2010 (µg/m 3 ) Year NOx NO 2 PM 10 PM Objectives a a There are no objectives for PM 2.5 that apply during these years, however the European Union limit value of 25 g/m 3 is to be met by The ADMS-Roads model has been run to predict baseline concentrations of nitrogen dioxide, PM 10 and PM 2.5 at each of the existing receptor locations identified in Appendix 7.1. Concentrations have been predicted at ground floor, although for Receptors 3 and 9, there is no relevant exposure at this level. The results, covering both the existing baseline and future year baseline (Without Scheme) scenarios, are set out in Tables 7.14 and The highest predicted concentration in 2010 and 2012 is at Receptor 7,

14 which is a ground-floor property on East Street, close to the junction with South Street / North Street / West Street. There are also predicted exceedences of the annual mean objective in 2010 and 2012 at Receptors 11, 12, 13 and 14. Receptors 11 and 12 are located in Rochford town centre (Figure 7.1) and Receptors 13 and 14 are located at the junction of Southend Road and Sutton Road to the south of Rochford (Figure 7.2) In 2012, baseline nitrogen dioxide concentrations are predicted to be higher than in 2010 as a result of the increased local traffic flows. The increase in flows includes baseline traffic growth, plus a contribution from other committed developments, which have the potential to be operational by This assessment appears to be inconsistent with the outcome of the Council s review and assessment reports that have identified no exceedences of the objectives within Rochford town centre, and no AQMA has been declared. It is important to note, however, that the nitrogen dioxide diffusion tubes deployed within Rochford are sited at approximately 3.5 metres height, whereas the modelling predictions for this assessment are at 1.5 metres height, representative of actual exposure. As concentrations decrease rapidly with increased height, this may explain some of the discrepancy. Table 7.14: Modelled Annual Mean Baseline Concentrations of Nitrogen Dioxide (µg/m 3 ) Location Annual mean Annual Mean Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Objective 40 40

15 Table 7.15: Modelled Baseline Concentrations of PM 10 and PM 2.5 a b Location PM 10 a PM 2.5 Annual mean ( g/m 3 ) No. Days >50 µg/m 3 Annual mean ( g/m3 ) Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Objective b 25 b The numbers of days with PM 10 concentrations greater than 50 g/m 3 have been estimated from the relationship with the annual mean concentration described in Defra, There are no objectives for PM 2.5 that apply during these years, however the European Union limit value of 25 g/m 3 is to be met by The predicted annual mean concentrations of PM 10 and PM 2.5 are below the objectives (or limit value) at all receptors in both 2010 and The numbers of days with PM 10 concentrations above 50 µg/m 3 are also below the objective at all receptors. 7.4 Main Impacts and Likely Significant Effects Construction Impacts The brownfield element of the site, where the built form development is proposed, is currently occupied by the disused Stambridge Mills flour mill. Prior to construction, these existing buildings will be demolished. The development will also benefit from improvements to the flood defence barrier, which will be an earth embankment constructed alongside the River Roach on the site of the existing but inadequate flood bunds. The greatest potential for construction impacts is likely to be from the demolition period, and from the passage of vehicles travelling across unpaved ground during periods of dry weather. There is also the potential for dust emissions during the handling of dusty materials and the cutting of stone/concrete. Dust may also be tracked out of the site onto the adjoining road network. The

16 construction phase may last up to 4 years, however, any impacts would be of a localised and temporary nature The construction site is considered to be Medium risk based on the criteria outlined in Table 7.6. Consequently, the construction activities are judged to be Moderate in scale. Based upon the criteria defined in Table 7.4, and assuming that standard mitigation measures are applied, significant dust-soiling impacts could therefore occur within a distance up to 50 m from the source, whilst PM 10 impacts could extend out to 15 m In addition, any new properties occupied prior to completion of construction, which lie within 50 m or 15 m of construction activities, would also be at risk of dust-soiling and increased PM 10 concentrations, respectively. Dust can also be tracked out of construction sites onto neighbouring roads. This can then be raised as airborne dust by passing vehicles. With mitigation, it is considered that there is a potential for significant dust to be found along off-site roads up to 100 m from the site entrance, with dust-soiling impacts potentially extending up to 25 m and elevated PM 10 impacts potentially extending up to 10 m, either side of these roads The Broomhills Care Centre lies within 50 m of construction activities relating to the flood defence barrier. It is therefore at risk of dust-soiling impacts during the construction of the embankment. Its southern most façade also lies within 15 m of these activities, and is therefore at risk of experiencing elevated PM 10 concentrations. Properties 6 to 11 Mill Lane lie within 25 m of the site access road and are therefore at risk of dust-soiling as a result of trackout. The façades of these properties also lie within 10 m of the road and are therefore at risk of elevated PM 10 concentrations as a result of trackout It should be noted, however, that it is the distance from the dust-emitting source that is important, and the majority of construction activity would take place away the Broomhills Care Centre, and that dust emissions from the access road can be very effectively controlled (see section 7.5), and it is not likely that significant impacts would occur along Mill Lane The locations that could potentially be affected by elevated dust levels and PM 10 concentrations during demolition and construction are shown in Figures 7.6 and 7.7, respectively The Crouch and Roach Estuaries SSSI lies adjacent to the flood defence barrier at its eastern extent, and thus within the 15 m buffer within which impacts may occur. The effects of construction activities on the SSSI habitats are considered further in Chapter 5, Ecology and Nature Conservation Any effects from construction activities will be temporary and relatively short lived, and will only arise during dry weather with the wind blowing towards a receptor, at a time when dust is being generated and mitigation measures are not being fully effective. Such conditions would only arise occasionally during the construction period, further limiting the potential for any impacts Mitigation measures to reduce and limit any impacts from the construction phase are set out in section 7.5. Operational Impacts Road Traffic Impacts 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 7.16, for both the Without Scheme and With Scheme scenarios.

17 Table 7.16: Predicted Concentrations of Nitrogen Dioxide (NO 2 ), PM 10 and PM 2.5 in Annual Mean ( g/m 3 ) and Number of Days with PM 10 > 50 g/m Without Scheme 2012 With Scheme NO 2 PM a 10 PM 2.5 NO 2 PM a 10 PM Location 2.5 Annual Annual Annual Annual Annual Annual Days Days Mean Mean Mean Mean Mean Mean Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Receptor Objectives b b a b The numbers of days with PM 10 concentrations greater than 50 g/m 3 have been estimated from the relationship with the annual mean concentration described in Defra, There are no objectives for PM 2.5 that apply during 2012, however the European Union limit value of 25 g/m 3 is to be met by Annual mean concentrations of nitrogen dioxide are predicted to exceed the objective in 2012 at Receptors 7, 11, 12, 13 and 14, whether the proposed scheme proceeds or not. At all other receptors they remain below the objective, whether the proposed scheme proceeds or not Predicted concentrations of PM 10 and PM 2.5 remain below the objectives in 2012, regardless of whether or not the scheme proceeds The changes in annual mean concentrations and days with PM 10 >50 µg/m 3 brought about by the scheme are shown in Table The magnitude of changes in annual mean nitrogen dioxide concentrations range from imperceptible (<0.4 µg/m 3 ) to small ( µg/m 3 ) at all receptors. The scheme makes an imperceptible difference to the annual mean concentrations of PM 10 and PM 2.5, and the number of days with PM 10 >50 µg/m 3. Using the criteria set out in Tables 7.8 and 7.9, the impacts are negligible at all receptors, apart from Receptors 7, 11 and 12, where the impacts are slight adverse with respect to nitrogen dioxide concentrations The overall air quality impact of additional traffic generated by the proposed development upon local air quality is judged to be minor adverse. This takes account of the factors described in Table 7.10.

18 Table 7.17: Change in Predicted Concentrations Between With Scheme and Without Scheme Conditions in 2012 a a Annual Mean NO 2 PM 10 PM 2.5 Location Annual Mean Annual Mean No. Days ( g/m 3 ) ( g/m 3 ) >50 µg/m 3 ( g/m 3 ) Receptor 1 <0.1 <0.1 0 <0.1 Receptor 2 <0.1 <0.1 0 <0.1 Receptor <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor Receptor <0.1 0 <0.1 Receptor <0.1 Receptor <0.1 0 <0.1 Receptor Receptor Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor <0.1 0 <0.1 Receptor Receptor <0.1 0 <0.1 Based on un-rounded values Impacts of Existing Sources on the Development The impacts of the existing traffic sources on air quality conditions for residents occupying the new residential units in the proposed development can be assessed from the model results for Receptors 23 to 28 (Table 7.18). All the values are well below the objectives. Air quality for future residents within the development would thus be acceptable. The impacts of emissions from the surrounding sources on new exposure being introduced within the development are therefore judged to be insignificant.

19 Table 7.18: Predicted Concentrations of Nitrogen Dioxide (NO 2 ) and PM 10 in 2012 for New Receptors in the Development Site a b 2012 With Scheme NO 2 (µg/m 3 ) PM 10 (µg/m 3 ) a PM 2.5 (µg/m 3 ) Location No. Days Annual Mean Annual Mean 3 Annual Mean >50 µg/m Receptor Receptor Receptor Receptor Receptor Receptor Objectives b The numbers of days with PM 10 concentrations greater than 50 g/m 3 have been estimated from the relationship with the annual mean concentration described in Defra, There are no objectives for PM 2.5 that apply during 2012, however the European Union limit value of 25 g/m 3 is to be met by Mitigation and Enhancement Construction Impacts Measures to mitigate dust emissions would be required during the construction phase of the development in order to reduce impacts upon nearby residential properties, and minimise any potential effects on ecological receptors. Guidance is available from the Building Research Establishment on controlling dust from construction sites (BRE, 2003). This reflects best practice experience of dust controls and has been used, together with the professional experience of the consultant, to draw up the following set of measures that should, where practicable, be incorporated into the specification for the works. Mitigation should be straightforward, as most of the necessary measures are routinely employed as good practice on construction sites. The measures are likely to include: Water-suppression to minimise dust during demolition activity; Phasing the development so that at any one time, construction activity is largely confined to relatively small portions of the site, away from occupied properties; Use of water-sprays to ensure that any unpaved routes across the site are maintained in a damp condition when in use; Use of consolidated surfaces close to residential areas; Imposition and enforcement of a 5 mph speed limit on unpaved ground; Hard surfacing of the proposed access roads at an early stage of the works; Minimising any dust generating activities on very dry or windy days; Sheeting of all lorries carrying materials on and off site; Locating and/or covering of stockpiles as far from sensitive locations as possible, and provision of appropriate hoardings; Wherever practicable, off-road plant to use Ultra-Low Sulphur Diesel and be equipped with exhaust after-treatment; Regular cleaning of all paved areas on-site;

20 Use of a jet-spray vehicle and wheel wash for all vehicles leaving the site; Regular use of a water-assisted dust sweeper on the access and local roads, as necessary, to remove any material tracked out of the site; and Use of water suppression during any cutting of stone or concrete 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 Even with these measures in place, there remains a risk that a small number of existing off-site properties might be affected by occasional dust-soiling impacts. Any effects will be temporary and relatively short lived, and will only arise during dry weather with the wind blowing towards a receptor, at a time when dust is being generated and mitigation measures are not being fully effective. The overall impacts during the construction phase with mitigation measures in place are judged to be slight adverse. Road Traffic Impacts The assessment has demonstrated that the proposed Stambridge Mills scheme has the potential to result in minor adverse impacts at a small number of existing residential properties in Rochford. It is therefore appropriate to consider mitigation to minimise the impacts of road traffic emissions generated by the proposed scheme The Stambridge Mills application includes an Interim Residential Travel Plan (Steer Davis Gleave, 2011). This document provides an outline and context to the formal Travel Plan which will be introduced when the development becomes operational. The Interim Residential Travel Plan outlines a number of initiatives to encourage sustainable transport, which will have positive benefits in terms of air quality, through reducing private vehicle trips and therefore reducing traffic emissions: Limited Parking: The development is designed to provide only 199 car parking spaces (including 12 disabled spaces) for the 96 residential units at the site, with no additional provision for visitor spaces; Cycle Facilities: The development will include 108 high-standard secure cycle parking spaces, including 12 designated for visitors to the development; Pedestrian Access: The development will include the construction of a new footpath and cycle path along Mill Road to Stambridge Road, and a new footpath to the west of the site linking to Rochford. These pedestrian facilities will provide improved access to buses operating on Stambridge Road, and trains from Rochford railway station, which provide services to south, west and central Essex, London, and beyond; Public Transport: The bus stop at the top of Mill Lane on Stambridge Road is proposed to be upgraded to encourage use. The upgrades will include a raised kerb for ease of access, and an improved bus shelter; Internet Access: The developer will ensure that broadband internet connections are made available to all residential units at the site. Good internet access will encourage the use of internet grocery shopping, and online purchases, which will reduce the need for private vehicle trips from the site; and Welcome Packs: All new residents will be provided with a Welcome Pack to introduce the Travel Plan and outline the sustainable transport facilities available at and near to the site The measures outlined above will all help to minimise traffic generation from the site, and therefore minimise the impacts to air quality. Further improvements to air quality will also be delivered through the introduction of more stringent emissions standards for road vehicles, largely via European legislation 7.5 Summary

21 7.5.1 The air quality impacts associated with the construction and operation of the proposed residential development at Stambridge Mills have been assessed. Existing monitoring within the study area shows acceptable air quality, with the majority of measured concentrations below the UK s air quality objectives The operational impacts of increased traffic emissions arising from the additional traffic on local roads, due to the development have been assessed. Concentrations have been modelled for twenty-two worst-case receptors, representing existing properties where impacts are expected to be greatest. In addition, the impacts of traffic from local roads on the air quality for future residents have been assessed at six locations within the new development itself It is concluded that for both the 2010 and 2012 baseline scenarios, annual mean concentrations of nitrogen dioxide exceed the objective at five locations, three in Rochford and two at the junction of Southend Road and Sutton Road, south of Rochford.. This assessment appears to be inconsistent with the outcome of the Council s review and assessment reports that have identified no exceedences of the objectives within Rochford town centre, and no requirement to declare an AQMA. It is important to note, however, that the nitrogen dioxide diffusion tubes deployed within Rochford are sited at approximately 3.5 metres height, whereas the modelling predictions for this assessment are at 1.5 metres height, representative of actual exposure. As concentrations decrease rapidly with increased height, this may explain some of the discrepancy With the proposed development in 2012, annual mean nitrogen dioxide at these five receptors remain above the objective. Annual mean nitrogen dioxide concentrations are predicted to remain below the objective at all other receptors in 2012, whether the proposed Stambridge Mill scheme proceeds or not Concentrations of particulate matter (PM 10 and PM 2.5 ) would remain below the objectives in 2012, whether the scheme is developed or not The proposed scheme is predicted to lead to small to imperceptible increases in annual mean nitrogen dioxide concentrations. The impacts associated with these increases are described as negligible at most receptor locations, and slight adverse at three receptor locations (Receptors 7, 11 and 12). The proposed scheme would only lead to imperceptible increases in PM 10 and PM 2.5 concentrations, and the impacts are all described as negligible Overall, the impact of the scheme on existing air quality is judged to be minor adverse. This conclusion is in accordance with the approach set out in paragraphs to and with the outcome described in Table Table 7.19: Factors Taken into Account in Determining the Overall Significance of the Proposed Development on Existing Factors Number of people affected by increases and/or decreases in concentrations and a judgement on the overall balance. The magnitude of the changes and the descriptions of the impacts at the receptors Whether or not an exceedence of an objective or limit value is predicted to arise in the study area where none existed before or an exceedence area is substantially increased. Uncertainty, including the extent to which Outcome of Assessment Imperceptible increases to annual mean nitrogen dioxide concentrations are predicted to occur across the majority of the study area. Increases to annual mean nitrogen dioxide concentrations above 1.0 µg/m 3 are predicted to occur at a very small number of properties in the vicinity of Receptors 11, 12 and 21 The change to annual mean nitrogen dioxide concentrations across the majority of the study area is negligible. Slight adverse impacts are predicted at Receptors 7, 11 and 12. Exceedences of the objectives are predicted to occur for both the baseline scenarios (2010 and 2012). The proposed development would not cause any new exceedences to occur, and the exceedence area would not be increased. The assessment has been founded on a

22 Factors worst-case assumptions have been made The extent to which an objective or limit value is exceeded Outcome of Assessment number of worst case assumptions; vehicle emission factors and background concentrations are assumed to remain unchanged from 2010, and traffic flows associated with all committed developments are included in the 2012 Baseline. Predicted annual mean concentrations are well above the objective at one receptor (Receptor 7) regardless of whether the proposed development proceeds or not The impacts of local traffic on the air quality for residents living in the proposed development have been shown to be acceptable at all locations within the proposed development site, with concentrations being below the air quality objectives. The impacts of emissions from the surrounding sources on new receptors being introduced within the development are therefore judged to be insignificant. This conclusion is in accordance with the approach set out in paragraphs to and with the outcome described in Table Table 7.20: Factors Taken into Account in Determining the Overall Significance of the Proposed Development on New Receptors Factors The number of people exposed to levels above the objective or limit value, where new exposure is being introduced. Uncertainty, including the extent to which worst-case assumptions have been made The extent to which an objective or limit value is exceeded Outcome of Assessment There would be no people exposed to concentrations above the objectives within the proposed development. The assessment has been founded on a number of worst case assumptions; vehicle emission factors an background concentrations are assumed to remain unchanged from 2010, and traffic flows associated with all committed developments are included in the 2012 Baseline There are no predicted exceedences within the proposed development The construction works have the potential to create dust. During construction it will therefore be necessary to apply a package of mitigation measures to minimise dust emission. Even with these measures in place, there remains a risk that a small number of existing off-site properties might be affected by occasional dust-soiling impacts. Any effects will be temporary and relatively short lived, and will only arise during dry weather with the wind blowing towards a receptor, at a time when dust is being generated and mitigation measures are not being fully effective. The overall impacts during the construction phase are judged to be slight adverse.

23 7.6 References BRE,2003. Controlling particles, vapour and noise pollution from construction sites. BRE Bookshop, London Carslaw, D, Beevers, S, Westmoreland, E and Williams, M, Trends in NOx and NO 2 emissions and ambient measurements in the UK. July Available at: Defra, The Strategy for England, Scotland, Wales and Northern Ireland. July Defra, Review & Assessment: Technical Guidance LAQM.TG(09). Defra, 2011a. UK Pollutant Release and Transfer Register prtr.defra.gov.uk Defra, 2011b. Defra Website at: EPUK, Development Control: Planning for (2010 Update) GLA, The Control of Dust and Emissions from Construction and Demolition: Best Practice Guidance. Available at: Institute of Management, Position on the Description of Impacts and the Assessment of their Significance, November ODPM, Planning Policy Statement 23: Planning and Pollution Control (PPS23). Rochford District Council, Rochford District Replacement Local Plan, available at: Rochford District Council, 2009a. Local Development Framework. Further information available at: Rochford District Council, 2009b. Core Strategy Submission Document. Available at: Rochford District Council, Rochford District Council Progress Report April Stationery Office, Regulations, 2000, Statutory Instrument 928. Stationery Office, (England) (Amendment) Regulations, 2002, Statutory Instrument Stationery Office, The Standards Regulations, 2007 (No.64). Stationery Office, East of England Plan. The Revision to the Regional Spatial Strategy for the East of England. Available at: Plan1.pdf Stationery Office, The Standards Regulations 2010 (No. 1001). Steer Davis Gleave, Stambridge Mills, Interim Residential Travel Plan Report. July 2011.

24 7.7 Glossary Standards A nationally defined set of concentrations for nine pollutants below which health effects do not occur or are minimal. Objectives A nationally defined set of health-based concentrations for nine pollutants, seven of which are incorporated in Regulations, setting out the extent to which the standards should be achieved by a defined date. There are also vegetationbased objectives for sulphur dioxide and nitrogen oxides. Exceedence A period of time when the concentration of a pollutant is greater than the appropriate air quality objective. This applies to specified locations. AQMA Management Area ADMS-Roads Atmospheric Dispersion Modelling System PM 10 Small airborne particles, more specifically particulate matter less than 10 micrometers in aerodynamic diameter. PM 2.5 NO 2 NO NOx g/m 3 HDV LDV TEA AADT Small airborne particles less than 2.5 micrometers in aerodynamic diameter Nitrogen dioxide. Nitric oxide. Nitrogen oxides (taken to be NO 2 + NO). Microgrammes per cubic metre. Heavy Duty Vehicles (> 3.5 tonnes) Light Duty Vehicles (<3.5 tonnes) Triethanolamine used to absorb nitrogen dioxide Annual Average Daily Traffic

25 7.8 Appendix 7.1 Receptor Locations Table A7.1.1: Description of Existing Receptor Locations Receptor Description Existing properties Receptor 1 Receptor 2 Receptor 3 Receptor 4 Receptor 5 Receptor 6 Receptor 7 Receptor 8 Receptor 9 Receptor 10 Receptor 11 Receptor 12 Receptor 13 Receptor 14 Receptor 15 Receptor 16 Receptor 17 Receptor 18 Receptor 19 Receptor 20 Receptor 21 Receptor West Street 44 West Street Residential property above Studio Rochford, 1 West Street 21 North Street 22 North Street Rose Cottage, 40 North Street 3 East Street 4 East Street Residential property above Dive Odyssea, 1 East Street The Old Watch House, 18 South Street 30 South Street 37 South Street 91 Southend Road 1 Sutton Road 94 Southend Road 97 Southend Road 1 Gloster Terrace, Stambridge Road Gloster Lodge, Stambridge Road White House, Stambridge Road Rose Cottage, Stambridge Road 1 Mill Lane 11 Mill Lane All receptors were modelled at ground floor (1.5 m). For receptors 3 and 9, this represents a worst-case scenario, as relevant exposure is located at first floor only.

26 7.9 Appendix 7.2 Model Verification Nitrogen Dioxide Most nitrogen dioxide (NO 2 ) is produced in the atmosphere by reaction of nitric oxide (NO) with ozone. It is therefore most appropriate to verify the model in terms of primary pollutant emissions of nitrogen oxides (NOx = NO + NO 2 ). The model has been run to predict the annual mean NOx concentrations during 2010 at the West Street, North Street, South Street, East Street, Southend Road and Anne Boleyn Sutton Road diffusion tube monitoring sites The model output of road-nox (i.e. the component of total NOx coming from road traffic) has been compared with the measured road-nox. Measured road-nox was calculated from the measured NO 2 concentrations and the predicted background NO 2 concentration using the NOx to NO 2 calculator available on the Defra website (Defra, 2011b) A primary adjustment factor was determined as the slope of the best-fit line between the measured road contribution and the model derived road contribution, forced through zero (Figure A7.2.1). This factor was then applied to the modelled road-nox concentration for each receptor to provide adjusted modelled road-nox concentrations. The total nitrogen dioxide concentrations were then determined by combining the adjusted modelled road-nox concentrations with the predicted background NO 2 concentration within the NOx to NO 2 calculator (Defra, 2011b). A secondary adjustment factor was finally calculated as the slope of the best fit line applied to the adjusted data and forced through zero (Figure A7.2.2) The following primary and secondary adjustment factors have been applied to all modelled nitrogen dioxide data: Primary adjustment factor : Secondary adjustment factor: The results imply that the model was under-predicting the road-nox contribution. This is a common experience with this and most other models. The final NO 2 adjustment is minor Figure A7.2.3 compares final adjusted modelled total NO 2 at each of the monitoring sites, to measured total NO 2, and shows a 1:1 relationship.

27 Figure A7.2.1: Comparison of Measured Road NOx to Unadjusted Modelled Road NOx Concentrations Figure A7.2.2: Comparison of Measured Total NO 2 to Primary Adjusted Modelled Total NO 2 Concentrations

28 Figure A7.2.3: Comparison of Measured Total NO 2 to Final Adjusted Modelled Total NO 2 Concentrations PM 10 and PM There are no nearby PM 10 or PM 2.5 monitors. It has therefore not been possible to verify the model for PM 10 or PM 2.5. The model outputs of road-pm 10 and road-pm 2.5 have therefore been adjusted by applying the primary adjustment factor calculated for road-nox. Numbers of Days with PM 10 Concentrations > 50 µg/m The number of exceedences of 50 μg/m 3 as a 24-hour mean PM 10 concentration has been calculated from the adjusted-modelled total annual mean concentration following the relationship advised by Defra (2009): A = B /B where A is the number of exceedences of 50 μg/m 3 as a 24-hour mean PM 10 concentration and B is the annual mean PM 10 concentration. The relationship is only applied to annual mean concentrations greater than 16.5 μg/m 3, below this concentration, the number of 24-hour exceedences is assumed to be zero.

29 7.10 Figures Figure 7.1: Rochford Town Centre Receptors Crown copyright All rights reserved. License number:

30 Figure 7.2: Southend Road / Sutton Road Receptors Crown copyright All rights reserved. License number:

31 Figure 7.3: Stambridge Road / Mill Lane Receptors Crown copyright All rights reserved. License number:

32 Figure 7.4: Development Receptors.

33 Figure 7.5: Diffusion Tube Locations Crown copyright All rights reserved. License number:

34 Figure 7.6: Areas Potentially Affected by Dust-soiling Impacts during the Construction Period. The green line indicates the Stambridge Mills site, whilst the pink line indicates the flood defence barrier location. Crown copyright All rights reserved. License number: Figure 7.7: Areas Potentially Affected by Elevated PM 10 Impacts during the Construction Period. The green line indicates the Stambridge Mills site, whilst the pink line indicates the flood defence barrier location. Crown copyright All rights reserved. License number: