Kent and Medway Air Quality Monitoring Network. ED AR2014/Issue 1 Date 17/07/2015 Ricardo-AEA in Confidence. [Keywords] Annual Report 2014

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1 [Keywords] Kent and Medway Air Quality Monitoring Network Annual Report 2014 Report for Medway Council on behalf of the Kent and Medway Air Quality Monitoring Network RRC/156/11 ED AR2014/Issue 1 Date 17/07/2015 Ricardo-AEA in Confidence

2 Kent and Medway Air Quality Monitoring Network i Customer: Medway Council Customer reference: RRC/156/11 Confidentiality, copyright & reproduction: This report is the Copyright of Medway Council and has been prepared by Ricardo- AEA Ltd under contract to Medway Council dated 19/07/2014. The contents of this report may not be reproduced in whole or in part, nor passed to any organisation or person without the specific prior written permission of Medway Council. Ricardo- AEA Ltd accepts no liability whatsoever to any third party for any loss or damage arising from any interpretation or use of the information contained in this report, or reliance on any views expressed therein. Contact: Christopher Conolly Ricardo-AEA Ltd Gemini Building, Harwell, Didcot, OX11 0QR, United Kingdom t: +44 (0) e: christopher.conolly@ricardo-aea.com Ricardo-AEA is certificated to ISO9001 and ISO14001 Author: Tim Bevington, Tom Buckland Christopher Conolly, and Alison Loader Approved By: Christopher Conolly Date: 17 July 2015 Ricardo-AEA reference: Ref: ED AR2014/Issue 1

3 Kent and Medway Air Quality Monitoring Network ii Executive summary This report presents the results for 2014 of air quality monitoring carried out by Ricardo-AEA on behalf of the Kent and Medway Air Quality Monitoring Network (KMAQMN). Results are presented for automatic measurements of ozone (O3), particulate matter (PM10 and PM2.5), sulphur dioxide (SO2) and nitrogen dioxide (NO2). These are compared with Air Quality Strategy (AQS) Objectives and Daily Air Quality Index bandings. This is followed by information on the health impacts of air quality. The report also includes details of significant pollution episodes during 2014, a description of air pollution trends and a discussion of the data in relation to sustainability indicators. Results are also presented for diffusion tubes used to indicatively measure NO2. Finally, the report gives details of progress made by each participating local authority with the review and assessment process. Network Performance The network achieved data capture of 88.4%, below the target of 90%. This was a result of fifteen analysers failing to achieve 90% data capture, with eight analysers failing to achieve 75% data capture. These included; Dartford Bean Interchange (NO2 & PM10), Dartford St Clements Roadside (NO2 & PM10), Dartford Town Centre (NO2 & PM10) and Swale Ospringe Roadside 2 (NO2 & PM10). The majority of the data losses during the year at the sites were due to instrument/equipment issues. Statistical summary and comparison with Air Quality Strategy Objectives All the monitoring sites covered in the report met the Air Quality Objectives for CO, SO2 and PM10 (PM10 annual mean and the 24-hr mean) in Two sites measured more than the ten permitted exceedances of the 8-hour running mean objective for O3. These were Rochester Stoke, which recorded 14 exceedances, and Canterbury, which recorded 25 exceedances. The exceedances occurred during periods of warm air temperatures during the summer. Eight roadside sites showed exceedances of the annual mean AQS objective for NO2. These are Canterbury St Peter s Place, Dartford Bean Interchange Roadside, Dartford St Clements Roadside, Dartford Town Centre Roadside, Maidstone A229 Kerbside, Swale Ospringe Roadside 2, Tonbridge Roadside 2 and Tunbridge Wells A26 Roadside. Air pollution episodes Several monitoring sites in the network reported NO2 concentrations in the Moderate band, according to the banding system used for the Daily Air Quality Index. This was consistent with NO2 measurements at other UK sites. Moderate concentrations of ozone were recorded on a number of occasions during These peaks are associated with meteorological conditions favourable for the formation of ozone. There were a large number of days when PM10 concentrations reached the Moderate banding. The Chatham Centre Roadside reached the Moderate band more frequently than the other sites. Five sites reached the High PM10 band. In 2014 there were no measured concentrations in the Moderate SO2 air pollution band although the only monitoring site still measuring SO2 was closed in early Health impacts of air quality The report also provide context on the health impact of air quality and the measured concentrations presented. In 2013 an estimate of 1050 early deaths as a result of just PM2.5 air pollution across Kent & Medway in 2010 was calculated by the Kent and Medway Air Quality partnership (K&MAQP) Health Sub Group, details are provided in section 4 of this report.

4 Kent and Medway Air Quality Monitoring Network iii Trends in pollution levels Concentrations of CO have remained below the EU Air Quality Directive limit value for 15 years. In 2014, CO measurement in the network ended with Chatham Luton Background closing in March. A decreasing trend started in 1998, but was broken by an increase during Concentrations have continued to decrease since Overall, NO2 concentrations remained relatively stable with the only increases seen at sites with poor data capture. Concentrations of O3 continue to fluctuate in response to meteorology, with the highest values typically occurring during warm sunny weather in the summer. However, concentrations at Maidstone Rural have decreased compared to the other sites. During 2014 rolling annual means for PM10 decreased at several sites, continuing the reduction seen in Concentrations of particulate matter were higher at roadside sites than at background sites likely to be due to the impacts of road traffic. Concentrations are also affected by transboundary transport of particulates and weather conditions; for example, westerly winds often bring cleaner air (and often wet weather) from the west and are often associated with lower concentrations of particulate pollution. Levels of PM2.5 at the Rochester Stoke site have stabilised and remain higher than at Chatham Centre Roadside. However, the dataset is fragmented and trends are therefore difficult to define. SO2 concentrations remain well below the objective level at all monitoring sites. Annual running mean at the majority of sites has remain stable, apart from at Rochester Stoke where there has been a steady increase. Sustainability indicators Over the network history there has been a general reduction in the overall sustainability indicator for PM10 at both urban and rural monitoring sites. There is a less clear trend in the sustainability indicator for ozone. Diffusion tube monitoring Most of the Kent and Medway local authorities supplement their automatic monitoring of NO2 with indicative measurements made using diffusion tubes which enable them to get more data whilst using budgets cost effectively. Twelve of the participating authorities have submitted NO2 diffusion tube data for the year This report presents a summary of NO2 diffusion tube results for each local authority. Review and assessment Each participating authority has provided an update on its position on the review and assessment process. These updates are included in Section 8.

5 Kent and Medway Air Quality Monitoring Network iv Table of contents 1 Introduction Monitoring results Changes to the network during Network performance Statistical summary and comparison with the Air Quality Strategy Objectives Air pollution episodes in Comparison with the Daily Air Quality Index Ozone (O3) PM10 particulate matter Sulphur Dioxide (SO2) Nitrogen Dioxide (NO2) Health impacts of air quality Health effects of pollutants Action that can be taken Cost of Air Pollution Sustainability indicators Trends in pollution levels, 1997 to Carbon monoxide (CO) Nitrogen dioxide (NO2) Ozone (O3) Fine particles (PM10 and PM2.5) Sulphur Dioxide (SO2) Diffusion tube results Introduction Site classifications Accuracy and bias adjustment Diffusion tube results Review and assessment update Ashford Borough Council Canterbury City Council Dartford Borough Council Dover District Council Gravesham Borough Council Maidstone Borough Council Medway Council Shepway District Council Swale Borough Council Thanet District Council Tonbridge and Malling Borough Council Tunbridge Wells Borough Council Appendices Appendix 1 Locations of monitoring sites operational in 2014 Appendix 2 Site names and site closures Appendix 3 UK national air quality objectives

6 Kent and Medway Air Quality Monitoring Network 1 1 Introduction The Kent and Medway Air Quality Monitoring Network (KMAQMN) was formed in 1997 to ensure a coordinated approach to air quality monitoring and reporting across the county. It also enables a cost effective approach to monitoring and data ratification to be employed. This report uses monitoring results from the network to describe how pollution levels compare to national standards and guidelines, describes the occurrence of pollution episodes over the past year and presents trends in concentrations. Results are presented for measurements of ozone (O3), particulate matter (PM10 and PM2.5), sulphur dioxide (SO2) and nitrogen dioxide (NO2). The more accurate measurements from continuous air quality monitors form the basis of the network and thus the main focus of this report. However, non-continuous diffusion tube monitoring results are also presented. Although more uncertain, this method is more economic and can allow a far more widespread indication of air concentration of NO2 than continuous monitoring. These results can provide a more local sense of pollution levels without the accuracy of automatic measurement. Because the very large number of diffusion tube monitoring sites throughout the county, results from each site are not discussed. Instead, they are shown in graphical form, with sites aggregated by site types. Recommendations for bias factor calculations are also given. The report also provides context on the health impact of air quality and the measured concentrations. In 2013 a new estimate of 1050 early deaths as a result of just PM2.5 air pollution across Kent & Medway in 2010 was calculated by the Kent and Medway Air Quality partnership (K&MAQP) Health Sub Group. Advice on where daily information on the local air quality is available, how the existing concentrations may impact your health and actions that an individual can take to reduce this risk are also provided. Finally, an update of each council s progress in the Review and Assessment process is presented. This report and its predecessors are available for downloading on the network internet pages 1. All network data used to compile the report are available for downloading online 2. Please note that local authorities may periodically undertake short term monitoring campaigns to assess concentrations at local hot spots identified by their Local Air Quality Management Review and Assessment processes. Please contact individual local authorities for results of these monitoring campaigns

7 Kent and Medway Air Quality Monitoring Network 2 2 Monitoring results 2.1 Changes to the network during 2014 During 2014 one site was decommissioned, with no new site opened, in the KMAQMN network. The decommissioned site was Chatham Luton Background. The sites within the network are presented in Appendix 1. Sites that have been closed during 2014 are highlighted in the key. Further site details are provided in Appendix 2, along with a full list of closed sites. 2.2 Network performance Table 1 shows the ratified data capture rates for each network analyser during The networks target is 90 % data capture for each analyser, although sites with data capture greater than 75 % are still considered likely to provide representative annual means. Any datasets with capture rates lower than 75 % are unlikely to be unrepresentative the full year. The average data capture for all the analysers in the KMAQMN was 88.4% with fifteen analysers failing to me 90% data capture. Eight analysers failed to achieve 75% data capture target, these included; Dartford Bean Interchange (NO2 & PM10), Dartford St Clements Roadside (NO2 & PM10), Dartford Town Centre (NO2 & PM10) and Swale Ospringe Roadside 2 (NO2 & PM10). The majority of the data losses during the year at the sites were due to instrument/equipment issues particularly at the Dartford sites. Table 1: Network data capture for 2014 (split over two pages) Site CO NO2 O3 PM10 PM2.5 SO2 Site Average Canterbury (AURN) Canterbury Military Road Canterbury PM10 (non- AURN) Canterbury Roadside Canterbury St Peters Place Chatham Centre Roadside (AURN) Chatham Luton Background (b) (21.30) (21.30) (20.50) (21.30) (20.90) Dartford Bean Interchange Roadside Dartford St Clements Roadside Dartford Town Centre Roadside Dover Centre Roadside Gravesham A2 Roadside Gravesham Industrial Background

8 Kent and Medway Air Quality Monitoring Network 3 Site CO NO2 O3 PM10 PM2.5 SO2 Site Average Maidstone A229 Kerbside Maidstone Rural Rochester Stoke (AURN) Swale Canterbury Road Swale Newington Swale Ospringe Roadside Swale St Pauls Street Thanet Airport Thanet Birchington Roadside Thanet Ramsgate Roadside Tonbridge Roadside Tunbridge Wells A26 Roadside Number of sites Number of sites < 90% Network mean (%) (a) Red underlined figures show data capture rates lower than 90 %. (b) Site/analyser closed during 2014; therefore data capture was only for the operational period. For sites where instruments were established or removed between 1st January 2014 and 31st December 2014, data capture is given as a proportion of the operational period (and in brackets and italics as a proportion of the full calendar year). 2.3 Statistical summary and comparison with the Air Quality Strategy Objectives Details of the annual average concentrations for 2014 are given in Table 2. Table 2 Annual mean concentrations, 2014 (split over two pages) Site CO NO 2 O 3 PM 10 PM 2.5 SO 2 Site Average Roadside Canterbury Military Road Canterbury Roadside Canterbury St Peter s Place

9 Kent and Medway Air Quality Monitoring Network 4 Site CO NO 2 O 3 PM 10 PM 2.5 SO 2 Site Average Chatham Centre Roadside - Dartford Bean Interchange Roadside - Dartford St Clement s Roadside - Dartford Town Centre Roadside (a) - 27 (a) 61 (a) - 25 (a) 44 (a) - 24 (a) Dover Centre Roadside (b) Gravesham A2 Roadside - Maidstone A229 Kerbside - Swale Canterbury Road (b) Swale Newington Swale Ospringe Roadside 2-41 (a) (a) (b) Swale St Pauls Thanet Birchington Roadside - Thanet Ramsgate Roadside Tonbridge Roadside Tunbridge Wells A26 Roadside (b) Background and Industrial urban/background Canterbury Chatham Luton Background Gravesham Industrial Background (b) Thanet Airport Rural Maidstone Rural Rochester Stoke Data are compared to the UK Air Quality Strategy (AQS) Objectives in Table 3. The objectives are listed in Appendix 3.

10 Kent and Medway Air Quality Monitoring Network 5 Table 3 Comparison of 2014 data with Air Quality Strategy Objectives PM10 Tapered Element Oscillating Microbalance (TEOM) data have been VCM corrected. Red, underlined figures show exceedances of an objective. CO NO2 O3 PM10 SO2 Period Running 8-hr mean 1-hr mean Annual mean Max daily running 8-hr mean 24-hr mean Annual mean 24-hr mean 1-hr mean 15- min mean Objective 10 mgm µgm µgm µgm µgm µgm µgm µgm µgm -3 Exceedance Object Roadside Canterbury Military Road Canterbury Roadside Canterbury St Peter s Place Chatham Centre Roadside Dartford Bean Interchange Roadside (a) 51 (a) - 11 (a) 27 (a) Dartford Clements Roadside St - 51 (a) 61 (a) - 11 (a) 25 (a) Dartford Town Centre Roadside Dover Centre Roadside Gravesham A2 Roadside Maidstone A229 Kerbside Swale Canterbury Road - 20 (a) 44 (a) - 13 (a) 24 (a) (b) 24 (b) (b) 18 (b)

11 Kent and Medway Air Quality Monitoring Network 6 CO NO2 O3 PM10 SO2 Swale Newington 3 Swale Ospringe Roadside (a) 41 (a) - 4 (a) (b) 18 (a) (b) Swale St Pauls Thanet Birchington Roadside Thanet Ramsgate Roadside Tonbridge Roadside 2 Tunbridge Wells A26 Roadside (b) 19 (b) Background and Industrial urban/background Canterbury Chatham Luton Background Gravesham Industrial Background Thanet Airport Gravesham Industrial Background (b) 15 (b) Rural Maidstone Rural Rochester Stoke (a) Annual data capture less than 75 %. (b) PM 10 data from TEOM analysers VCM corrected. Some sites use the Tapered Element Oscillating Microbalance (TEOM) to measure PM10.The high operating temperature of the TEOM can cause evaporation of the volatile component of the measured PM10. The current Defra Technical Guidance for Local Air Quality Management (LAQM.TG (09)) therefore requires (TEOM) data to be corrected to reference equivalent concentrations for comparison with objectives. This is to be done using the King s College London Volatile Correction Model (VCM) ( The VCM works by using the volatile particulate matter measurements provided by nearby FDMS-TEOM instruments (within 130 km) to assess the loss of PM10 from the TEOM; this value is then added back onto the TEOM measurements. The resulting

12 Kent and Medway Air Quality Monitoring Network 7 corrected measurements have been demonstrated as equivalent to the European Reference Method. This is a change to the earlier method of applying a correction factor of 1.3 to TEOM data. To comply with this requirement, the calculation of all statistics for TEOM PM10 data for 2014 is based on data corrected using the VCM. Because only recent data are available from FDMS-TEOM analysers it is not possible to correct all historical TEOM data in the same manner. TEOM data with the 1.3 correction factor applied are also currently still used for near-real-time air quality reporting through the KMAQMN website. For this reason all of the PM10 data presented in Sections 5 and 6 showing longer terms trends are based on TEOM data corrected with a factor of 1.3. However, in this section (Section 2.3) and Section 3, where comparisons are made with the Air Quality Strategy Objectives, the VCM corrected TEOM data are presented. An FDMS (Filter Dynamics Measurement System) is a self-referencing airborne particulate monitor based on TEOM technology. The standard TEOM uses first principle physics to measure the mass of particles collected on a filter. The FDMS measures the core and volatile fractions of the collected mass by using a technique to measure the effects of these materials as they collect on the filter. The TEOM analysers at the Chatham Centre and Maidstone Rural sites were upgraded to FDMS-TEOM analysers during Correction of these data is therefore not required. All PM10 Beta Attenuation Monitor (BAM) data have been corrected to gravimetric equivalent by using a factor of 0.83, as recommended by the LAQM Technical Guidance LAQM.TG(09). These values are used throughout the report. As with the previous years all sites met the CO and SO2 Objectives for Two of the three sites measuring ozone during the summer of 2014 measured more than 10 exceedances of the ozone maximum daily 8-hour running mean objective. At Canterbury there where 25 exceedances whilst there were 14 at Rochester Stoke. These exceedances were driven by strong sunlight mainly during the summer months. As reported in previous years there are a number of roadside sites that continue to exceed the annual mean AQS objective of 40 μgm -3 for NO2. These are Canterbury St Peter s Place, Dartford Bean Interchange Roadside, Dartford St Clements Roadside, Dartford Town Centre Roadside, Maidstone A229 Kerbside, Swale Ospringe Roadside 2, Tonbridge Roadside 2 and Tunbridge Wells A26 Roadside. It should be noted that the three Dartford sites had data capture less than 75% so should be treated with caution as episodes may be missed. Although, these sites have recorded an exceedance of this objective in all previous years (see section 5 for trend analysis). As in 2012 & 2013, the highest annual mean concentration was measured at Dartford St Clements Roadside location (61 µgm-3). This site also exceeded the hourly mean objective of 200 µgm times in 2014, therefore exceeding the 18 permitted occurrences. Dartford Town Centre Roadside also exceeded (20 times) the hourly mean objective. All sites met the annual mean PM10 objectives of 40 μgm -3 and no sites exceeded the 35 allowed exceedances of the 24 hour mean objective of 50 µgm -3. A more detailed review of exceedances is provided in Section 3.3.

13 3 Air pollution episodes in 2014 Kent and Medway Air Quality Monitoring Network 8 In this section the data are firstly compared to the new Daily Air Quality Index bandings launched by Defra in January The exceedances of the Air Quality Strategy (AQS) objectives are then investigated on a pollutant-by-pollutant basis and a number of specific episodes are discussed. There were no exceptional pollution events in Kent and few across the UK as a whole during However, there were a few localised pollution incidents involving specific pollutants that are considered below. 3.1 Comparison with the Daily Air Quality Index The Daily Air Quality Index and its banding system, recommended by Committee on Medical Effects of Air Pollutants (COMEAP), is used to provide near-real-time information about air quality levels and to allow sensitive individuals to take action if required. The system uses an index numbered 1 to 10, divided into four bands ( Low to Very High ) to provide information about air pollution levels in a simple way, similar to the pollen index. The air quality bandings were updated at the beginning of The descriptions associated with each band are provided in Table 4 presents the numbers of days when pollutant concentrations within the Kent and Medway network reached Moderate or High levels. The Kent Air website ( provides a map that highlights the latest pollution levels at the automatic monitoring locations across Kent & Medway. Each location is colour coded based on Defra s Daily Air Quality Index, which is calculated on the daily maximum readings record at each site. The index aims to both informs users of the local levels of air pollution and provides relevant recommended actions and health advice. Table 4: Air quality bandings and their descriptions Band Index Accompanying health messages for atrisk individuals* Accompanying health messages for the general population Low 1-3 Enjoy your usual outdoor activities. Enjoy your usual outdoor activities. Moderate 4-6 Adults and children with lung problems, and adults with heart problems, who experience symptoms, should consider reducing strenuous physical activity, particularly outdoors. High 7-9 Adults and children with lung problems, and adults with heart problems, should reduce strenuous physical exertion, particularly outdoors, and particularly if they experience symptoms. People with asthma may find they need to use their reliever inhaler more often. Older people should also reduce physical exertion. Very High 10 Adults and children with lung problems, adults with heart problems, and older people, should avoid strenuous physical activity. People with asthma may find they need to use their reliever inhaler more often. Enjoy your usual outdoor activities. Anyone experiencing discomfort such as sore eyes, cough or sore throat should consider reducing activity, particularly outdoors. Reduce physical exertion, particularly outdoors, especially if you experience symptoms such as cough or sore throat

14 Kent and Medway Air Quality Monitoring Network 9 Table 5 Numbers of days with "Moderate" or above concentrations in 2014 NO 2 O 3 PM 10 PM 2.5 SO 2 Moderate Moderate Moderate High Moderate High Moderate Roadside Canterbury Military Road Canterbury Roadside Canterbury St Peter s Place Chatham Centre Roadside Dartford Bean Interchange Roadside Dartford St Clement s Roadside Dartford Town Centre Roadside Dover Centre Roadside Gravesham A2 Roadside Maidstone A229 Roadside Swale Canterbury Road Swale Newington 3 Swale Ospringe Roadside (a) 0 (a) (a) 0 (a) (a) 0 (a) Swale St Pauls Thanet Birchington Roadside

15 Kent and Medway Air Quality Monitoring Network 10 NO 2 O 3 PM 10 PM 2.5 SO 2 Thanet Ramsgate Roadside Tonbridge Roadside 2 Tunbridge Wells A26 Roadside (a) 0 (a) Background and Industrial urban/background Canterbury Chatham Luton Background (a) 0 (a) Gravesham Industrial Background Thanet Airport Maidstone Rural Rochester Stoke Rural (a) Based on VCM corrected data. Carbon monoxide was only measured at one site and there were no days when concentrations reached Moderate concentrations or above. This pollutant has therefore not been included in Table 5. Several sites recorded days with Moderate or above NO2 concentrations during On 20 th January Dartford St Clements recorded High concentrations. The remaining days when a Moderate or above concentrations were measured at individual sites throughout the year. Several days measured Moderate ozone concentrations during 2014 at Canterbury the two rural sites at Maidstone Rural and Rochester Stoke. This is consistent with other background and rural stations across southern England. In some previous years (prior to 2012) bandings for PM10 were calculated based on the assumption that TEOM reference equivalent PM10 = TEOM x 1.3. However, in the above table the numbers of days Moderate or above for TEOM monitors have been calculated using VCM corrected data. All of the PM10 sites, apart from Dover Centre Roadside, recorded days with concentrations in the Moderate band during the year, the highest number being 14 at the Chatham Centre Roadside site. There were also 18 such days at Dartford Town Centre Roadside, 16 recorded at Tunbridge Wells A26 Roadside and 13 at Dover Centre Roadside, Dartford St Clements Roadside and Thanet Birchington Roadside. Five sites had days with High PM10 concentrations, compared to three in Maidstone Rural recorded High concentrations four times; Dartford Town Centre and Dartford Bean Interchange Roadside on three occasions, Dartford St Clement s Roadside twice and Chatham Centre Roadside once. It should be noted that as the data capture at the Dartford monitoring sites was less than 75% the results should be treated with caution as pollution episodes could have been missed. On several of the dates concerned, elevated concentrations of particulate matter were also measured at other sites in the

16 Kent and Medway Air Quality Monitoring Network 11 area. It therefore appears that the elevated concentrations on several occasions were due to regional particulate episodes and not specifically local sources. There are only two sites that measure PM2.5 in the network: both are part of Defra s Automatic Urban and Rural Network (AURN). Chatham Centre Roadside had 18 Moderate and no High day. Whereas, the more rural site of Rochester Stoke had 19 Moderate and 2 High days. Moderate SO2 concentrations are now rare. This was reflected in 2014 with no Moderate or above days recorded, as in Description of Episodes: 20 th January There were elevated levels of PM10 and NO2 pollution on the 20 th of January with levels at roadside locations in Kent and Medway in the moderate and high levels. The cause of the episode appeared to be mostly due to primary pollution from traffic sources combined with low wind speeds caused by high pressure parts of northern Europe and the North Sea. This led to poor dispersion of the traffic emissions and elevated concentrations. Less settled conditions prevailed on the 21 st leading to reduction in pollutant concentrations hence limiting the length of the episode. 9 th March There was a brief elevation in concentrations of PM10 and PM2.5 on the 9 th March due to stable anticyclone (high pressure system) creating calm conditions. Local air masses and some continental contribution lead to increases in particulate levels particularly in urban and roadside locations. 12 th to 14 th March A slowly circulating stable anticyclone (high pressure system) lead to lower temperatures at night causing fog formation and lack of dispersion of pollution. Continental air masses also contributed to the levels of PM10 and PM2.5 found locally. Elevated concentrations were also observed in London and the south east with moderate and high levels of air pollution recorded in Kent at some sites during this episode. 28 th to 29 th March Moderate air pollution was observed for PM10 and PM2.5 in late March (28 th and 29 th ). Particulate build up resulted from light easterly winds preventing significant dispersion combined with some continental contribution from Europe. Calm conditions continued over the weekend where the conditions continued allowing further local particulate increases from local emissions in addition to the continental contribution. Increased dispersion occurred later in the weekend allowing better dispersion. 1 st to 3 rd April There was a highly publicised pollution episode in early April, this resulted in levels reaching High in Kent and were due to increases in PM10 and PM2.5 concentrations. On the 1st of April there was a slight increase in concentrations of particulate matter measured in Kent with further elevation in concentrations on the 2 nd of April. High pollution was recorded in parts of Kent throughout the 2 nd of April particularly in urban and traffic related sites where exhaust emissions influenced particulate concentrations. Increases in particulate concentrations were observed during the morning of the 2nd April and concentrations did not subside as is often observed. The reason behind this thought to be due to low speed, low altitude continental air masses (mostly from France) adding to local exhaust emissions. On the 3 rd of April the levels decreased to mostly to moderate in Kent due to a change in the wind direction with air masses coming from the west rather than from the continent. Earlier in the week there was also Saharan dust deposits observed which raised the public interest in pollution levels. 20 th and 21 st April Moderate levels of PM10 and PM2.5 was observed in the Kent and Medway area on the 20 th April with some moderate levels still being observed at four sites on the 21 st April. The levels observed were due to continental air and local contributions.

17 Kent and Medway Air Quality Monitoring Network 12 4 th to 5 th May and 17 th to 20 th May Elevated levels of ozone were recorded at some measurement sites in Kent and Medway with Moderate levels were recorded at Canterbury and Rochester Stoke sites. The elevated levels of ozone during this period were caused by prolonged sunny conditions 16 th to 19 th September Elevated levels of particulates were recorded at some sites in the Kent and Medway Network. This was due to south easterly winds bringing in particulate pollution from the continent and still conditions leading to a build-up of emissions. Elevated levels were forecasted for 18 th and 19 th September and a high pollution warning was published on Defra s UK-Air ( 19 th to 20 th November Continental air effected the south east of the UK bringing pollution from the continent on the 19 th and 20 th of November. In addition to this there was poor dispersion of local emissions. Moderate levels were reached at some sites for NO2 and PM10/2.5 during this period mainly at the roadside locations in Kent. As winds increased so did dispersion and levels dropped later in the week. 3.2 Ozone (O3) The maximum hourly averaged ozone concentration in 2014 was 158 μgm -3 at the Canterbury monitoring site on 18 th and 19 th May. This reached the Moderate air quality band at air pollution index 6. There were no incidents of High air pollution or above due to ozone in the KMAQMN during Figure 1 shows that there were a number of distinct periods of increased photochemical pollution during 2014, compared with the AQS 8-hour running mean objective of 100 µgm -3. Most noticeable periods of photochemical pollution occurred in March (two days) April (four days), May (twenty-six days), July (ten days), July (twelve days) August (two days) and September (one day). As anticipated, ozone concentrations in Kent followed a similar pattern to UK wide ozone concentrations during The occasions when the KMAQMN recorded elevated ozone concentrations during 2014 were due to short periods of favourable weather conditions for ozone formation. These are generally characterised by settled weather with high pressure dominating and low percentage cloud cover. Figure 1 Periods and number of sites when ozone maximum 8-hour running mean concentrations exceeded 100µg/m3

18 3.3 PM10 particulate matter Kent and Medway Air Quality Monitoring Network 13 During 2014 a large number of sites across Kent exceeded the 50 μgm -3 daily mean AQS objective. However no sites did so on more than the 35 days permitted during a calendar year. Five of the 16 sites that were operational during the whole of 2014 exceeded the 50 μgm -3 level on at least 15 separate days during the year. The frequency and magnitude of exceedances is illustrated in Figure 2. Figure 2 Periods and number of sites when gravimetric equivalent PM10 24-hour mean concentrations exceeded 50 g m-3. TEOM data have been VCM corrected 3.4 Sulphur Dioxide (SO2) Sulphur dioxide is now very much a localised problem across the UK, only recognised as causing possible problems in areas close to: Domestic coal burning. Diesel and steam railways. Industrial use of high sulphur fuels. Shipping. There were no exceedances of the 266 μgm minute SO2 objective recorded in the KMAQMN in The maximum 15-minute concentration of 104 μgm -3 was recorded at Maidstone Rural monitoring site. The sites are well below the objective target of 35 or less exceedances. 3.5 Nitrogen Dioxide (NO2) Exceedances of the 200 μgm -3 hourly air pollution standard during 2014 occurred at seven sites. These were Dartford Bean Interchange Roadside, Dartford St Clements Roadside, Dartford Town Centre Roadside, Maidstone A229 Kerbside, Swale Canterbury Road, Swale Newington 3 and Tonbridge Roadside 2. Two site exceeded the 18 permitted exceedances for the year - these where Dartford St Clement s Roadside and Dartford Town Centre with 51 and 20 hours above the 200 μgm -3 objective respectively. The exceedances seen in Kent were spread throughout the year, usually with one or two site exceedances on a single day. However, there was one occasion when there was four exceedances on

19 Kent and Medway Air Quality Monitoring Network 14 the same day as can be seen in Figure 3 below. The exceedance at four sites occurred on 20 th January. As in previous years, exceedances occurred predominantly during the winter months, which is generally due to periods of cold weather leading to poor dispersion and higher emissions from sources such as motor vehicles and potentially domestic and industrial heating demands. The maximum hourly averaged concentration of nitrogen dioxide observed in 2014 was 567 μgm -3 measured at Dartford St Clements Roadside. Figure 3 Periods and number of sites when NO2 hourly mean concentrations exceeded 200 μg m -3

20 4 Health impacts of air quality Kent and Medway Air Quality Monitoring Network 15 A variety of air pollutants have known or suspected harmful effects on human health and the environment. In most areas of Europe, these pollutants are principally the products of combustion from space heating, power generation or from motor vehicle traffic. Pollutants from these sources may not only prove a problem in the immediate vicinity of these sources but can travel long distances. As seen in section 3 of this report air in Kent can be not only influenced by local factors but also continental air from mainland Europe. Generally if you are young and in a good state of health, moderate air pollution levels are unlikely to have any serious short term effects. However, elevated levels and/or long term exposure to air pollution can lead to more serious symptoms and conditions affecting human health. This mainly affects the respiratory and inflammatory systems, but can also lead to more serious conditions such as heart disease and cancer. People with lung or heart conditions may be more susceptible to the effects of air pollution. 4.1 Health effects of pollutants The text below shows the types of health effects experienced by the most common pollutants at when observed at elevated levels: Carbon Monoxide (CO) Carbon Monoxide prevents the uptake of oxygen by the blood. This can lead to a significant reduction in the supply of oxygen to the heart, particularly in people suffering from heart disease. Concentrations of CO in the UK have reduced significantly so this pollutant is less of a concern currently Nitrogen Dioxide (NO2) Long term exposure to NO2 can lead to bronchitis in asthmatic children and a reduction in lung function growth. NO2 also irritate the lungs hence increasing the symptoms sufferers of lung disease Ozone (O3) Ozone at ground level is one of the constituents of photochemical smog which can be formed by the reaction with sunlight and pollutants such as nitrogen oxides (NOx) and volatile organic compounds (VOCs) both of which are emitted by vehicles as well as some industries. The highest levels of ozone pollution occur during periods of sunny weather. Elevated concentrations of ozone in the air can have a noticeable effect on health, triggering asthma, causing breathing problems, reducing lung function and potentially causing lung diseases Particulate matter (PM) PM is thought to affect more people than any other pollutant (WHO) 3. Particulate matter composition vary between locations however generally consists of sulfates, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water and are thought to be a complex mixture of solid and liquid particles of organic and inorganic substances suspended in the air. Particles with smaller diameter are thought to be more likely to damage health, which can penetrate and lodge deep inside the lungs. Chronic exposure to particles contributes to the risk of developing cardiovascular and respiratory diseases, as well as of lung cancer. There is a close, quantitative relationship between exposure to high concentrations of small particulates (PM10 and PM2.5) and increased mortality or morbidity. This has been established for both daily and over time hence why government and local authorities are concerned about air concentrations of particles Sulphur Dioxide (SO2) SO2 can also irritate the airways of the lungs or cause inflammation of the respiratory tract, increasing the symptoms of those suffering from lung diseases. Concentrations of SO2 in the UK have reduced significantly so this pollutant is less of a concern currently. 3 WHO Fact sheet N 313 March 2014

21 4.2 Action that can be taken Kent and Medway Air Quality Monitoring Network 16 When levels of air pollution increase it would be sensible for those who have noticed that they are affected to limit their exposure to air pollutants. This does not mean staying indoors, but reducing levels of exercise outdoors would be reasonable. The following advice has been provided and maybe suitable to the people however members of the public with health conditions should take professional advice with regard to their own health condition and circumstances. Older people and those with heart and lung conditions might want to avoid exertion on High pollution days. Adults and children with asthma should check that they are taking their medication as advised by their health practitioner and may notice that they need to increase their use of inhaled reliever medication. Adults with heart and circulatory conditions should not modify their treatment schedules on the basis of advice provided by the air quality index: such modification should only be made on a health practitioner's advice. Some athletes, even if they are not asthmatic, may notice that they find their performance is poorer than expected when levels of a certain air pollutant (ground level ozone) are High, and they may notice that they find deep breathing causes some discomfort in the chest: This might be expected in summer on days when ground level ozone levels are raised. This does not mean that they are in danger but it would be sensible for them to limit their activities on such days. 4.3 Cost of Air Pollution Air quality has improved considerably in the UK in recent decades due to new cleaner technology and tighter environmental legislation, which have reduced emissions from industry. Despite these improvements, the Committee on the Medical Effects of Air Pollutants (COMEAP) estimated that long term exposure to air pollution had an effect equivalent to 29,000 deaths a year in the UK in and probably causes more mortality and morbidity than passive smoking, road traffic accidents or obesity. The financial burdens of the health impacts in the UK are considerable. In 2005, estimates for manmade particulate pollution alone in the UK were billion a year (Defra Air Quality Strategy, 2007). This is likely to be an under-estimate as it ignores the impact on morbidity, costing only mortality. There are also additional costs to the NHS from respiratory hospital admissions triggered by air pollution. There are clear links between asthma and air quality and although not all admissions will be attributable to poor air quality there were over 74,000 emergency admissions to hospital because of asthma in 2007/08. In 2013 a new estimate of 1050 early deaths as a result of just PM2.5 air pollution across Kent & Medway in 2010 was calculated by the Kent and Medway Air Quality partnership (K&MAQP) Health Sub Group. This was using the methods recommended in the statement (Aug 2012) Estimating the mortality burden of particulate air pollution at the local level from the Committee on the Medical Effects of Air Pollutants (COMEAP), the Government s official advisory panel. Figure 4 shows estimated early deaths by local authority. The plot below uses PM2.5 concentrations in the relevant LAs and also accounts for the population size by local authority (2011 Census). It should be noted that there may be additional deaths that may have occurred from other pollutants as well but the subgroup did not undertake these calculations. This estimate is thought to be potentially on the low side since it is based on background levels and does not take into account the higher population densities in urban areas where exposure to higher levels of pollution is experienced. 4 The Mortality Effects of Long-Term Exposure to Particulate Air Pollution in the United Kingdom Produced by the Health Protection Agency for the Committee on the Medical Effects of Air Pollutants 2010

22 Kent and Medway Air Quality Monitoring Network 17 Figure 4 Early deaths in Kent & Medway from PM2.5 pollution in Sustainability indicators This section of the report provides an analysis of the numbers of days when air pollution was Moderate or higher for any one of five pollutants measured. This measure is used as a sustainability indicator for air quality. The air quality indicator approach was introduced in 1999 to support the UK Sustainable Development Strategy. This strategy was updated in 2005 and the opportunity was taken to introduce two new air quality indicators to better reflect the effects on health of long-term exposure to lower levels of pollution. The sustainability indicators make use of the index and banding system recommended by the Committee on Medical Effects of Air Pollutants (COMEAP). As explained in section 3, this system uses four bands, Low, Moderate, High and Very High to convey information about air pollution in a simple way. The indicators are as follows: Annual average urban PM10 particulate concentrations (roadside and background) Annual average ozone concentrations measured as the daily maximum 8-hour running mean (rural and urban background) Total numbers of days on which one or more of the specified pollutants were recorded as causing Moderate or worse air pollution (the original headline indicator). The two new air quality indicators allow trends to be monitored for annual exposure to the two pollutants believed to have the greatest effect on human health, particles and ozone. For particles, the indicator has been introduced because there is evidence that suggests long-term exposure to even low levels of particulate (PM10) may have a significant effect on public health. The annual mean values for particulates are a useful measure of overall exposure to particulates at all concentrations. The annual average measures of PM10 have been included to reflect this. The impact of long term exposure to low levels of ozone is currently less clear. In the absence of a clear lower limit known to have a health impact, the parameter used in the new indicator gives the best representation of the total annual impact of the short term effects of ozone pollution. Figure 5 and Figure 6 present the data for the PM10 and ozone annual average indicators for the UK as a whole, and across the Kent and Medway network. Ozone is split between rural and urban sites and

23 Kent and Medway Air Quality Monitoring Network 18 PM10 between roadside and urban. The PM10 indicator is calculated from the average annual mean gravimetric PM10 concentration at all sites (VCM corrected from 2008 onwards). The ozone indicator is calculated from the maximum daily 8-hour average ozone concentration (i.e. the average across all sites of each day s highest 8-hour running average concentration). From a visual assessment of the plotted data in Figure 5 there has been an observable decrease in particulate concentrations in the UK since As highlighted in previous reports it should be noted that the number of sites in the Kent and Medway network was initially relatively small, hence the indicator may have been influenced by the introduction of individual sites with high or low concentrations. Since 2003 there is an observable decrease in concentrations of PM10 in all of the datasets presented in Figure 5. There are still annual fluctuations in average concentrations which are likely to be due to changes in meteorology. The overall trend in concentrations still appears to be decreasing. Figure 6 shows a slight downward trend in the mean daily maximum running 8-hour mean concentration of ozone in Kent since If the full data set is reviewed the reduction actually appears minimal. No trend is apparent at the UK urban and rural sites. The increase in concentrations at the UK urban sites in the later 1990s and early 2000s could be due to the more limited number of sites during this period. It should be noted that, as in 2013, the Kent Urban Ozone results are only based on one site due to the closure of the Chatham Luton Background Ozone measurement in early In previous years, this site has measures lower ozone concentrations reducing the average for Kent Urban ozone sites. This reflected in the increase Kent Urban ozone indicator in 2013 and The UK rural and urban statistics have been updated for some previous years in Defra s report National Statistics in the UK, 1987 to Therefore, Figure 6 has been updated to reflect these changes and does not match the graph found in previous reports. Figure 5 Annual average PM10 air quality indicator for Kent and UK (where required VCM corrected 2008 onwards)

24 Kent and Medway Air Quality Monitoring Network 19 Figure 6 Mean daily maximum running 8-hour average ozone air quality indicator for Kent and UK Figure 7 Headline air quality indicator for Kent and UK the total number of days with pollutant concentrations recorded Moderate or above 1997 to 2014

25 Kent and Medway Air Quality Monitoring Network 20 Table 6 Numbers of days when one or more of specified pollutants recorded "Moderate" or above concentrations - Headline Air Quality Indicator (2000 to 2014) Ashford Background Chatham Luton Background Chatham Roadside Folkestone Suburban Maidstone A229 Kerbside Maidstone Rural Rochester Stoke Thanet Rural Kent Overall Rural Indicator Kent Overall Urban Indicator UK Rural Indicator* UK Urban Indicator* (a) Not used in the calculation of the rural indicator as data capture below 75% for year or in April-September for ozone. * UK Indicators have new bandings applied from 2010 as detailed in Air Quality Statistics in the UK release April 2014 ( It should also be noted that some data was incorrectly entered in to Table 6 in the 2013 report therefore, there will be difference in this table between reports

26 Kent and Medway Air Quality Monitoring Network 21 Figure 7 Headline air quality indicator for Kent and UK the total number of days with pollutant concentrations recorded Moderate or above 1997 to 2014 Table 6 Numbers of days when one or more of specified pollutants recorded "Moderate" or above concentrations - Headline Air Quality Indicator (2000 to 2014) presents the number of days on which Moderate or higher pollutant concentrations were measured at long standing urban and rural sites in the Kent Network. The data presented in the above table have been used along with older data to prepare Figure 7. It should be noted that all of the Kent data have been updated to reflect the new bandings whereas only 2010 onwards have been updated for the UK indicators*. The largest peaks are observed in 2003 which were as a result of the hot summer contributing to elevated levels of pollutants. There was a large drop in the number of days where moderate levels or above were recorded in 2009 and As the UK indicators follow the same patterns in these years it is likely that the reductions were due to a poor summer leading to lower levels of ozone formation. The general annual fluctuations in the indicators and concentrations observed would need further local investigation. There was an increase in the number of Moderate or above days at rural sites in Kent during 2013, which has continued into 2014, which is not reflected nationally. At the two rural sites in Kent, Maidstone Rural and Rochester Stoke, this was due to an increase in the number of days where ozone concentrations were Moderate or above. A breakdown of which pollutants contribute to the Moderate or above concentrations can be found in to Figure 13. Figure 8 presents the pollutants that recorded concentrations of "Moderate" or above at each monitoring site. The graph breaks down each site by the number of days that an individual pollutant's concentration was "Moderate" or above. Due to it being possible that more than one pollutant can be "Moderate" or above on a particular day the sum of individual pollutants maybe greater than 'Total Days'.

27 Kent and Medway Air Quality Monitoring Network 22 Figure 8 Pollutants that recorded concentrations of "Moderate" or above at during 2014

28 Kent and Medway Air Quality Monitoring Network 23 Figure 9 to Figure 13 show the long term trend of concentrations of "Moderate" or above recorded at the sites detailed in Figure 7 Headline air quality indicator for Kent and UK the total number of days with pollutant concentrations recorded Moderate or above 1997 to 2014 Table 6 by pollutant and total days.

29 Kent and Medway Air Quality Monitoring Network 24 Figure 9 on the next page shows the pollutants at the background monitoring site Chatham Luton Background that have resulted in concentrations measured as "Moderate" or above. In previous years, 2009 and 2010 excluded, ozone levels have resulted in the majority of days that are "Moderate" or above, with the highest number of days in It should be noted that Ozone measurement was ceased in early 2013 at the site and the site closed in March 2014.

30 Kent and Medway Air Quality Monitoring Network 25 Figure 9 Pollutants that recorded concentrations of "Moderate" or above at Chatham Luton Background between 2000 and 2014 Figure 10 Pollutants that recorded concentrations of "Moderate" or above at Chatham Roadside between 2000 and 2014

31 Kent and Medway Air Quality Monitoring Network 26 Figure 10 above breaks down the pollutants that recorded concentrations of "Moderate" or above at the site "'Chatham Roadside". Since monitoring of PM2.5 began at the site in 2010 the number of "Moderate" or above days has increased. PM10 can be used to compare the data to years before PM2.5 monitoring was undertaken. Although the last four years have seen a higher than average number of "Moderate" or above days at the site there is no overall trend. NO2 is also monitored at this site and has not resulted in any "Moderate" or above days. Figure 11 Pollutants that recorded concentrations of "Moderate" or above at Maidstone A229 Kerbside between 2000 and 2014 Figure 11 above shows the number of "Moderate" or above days at Maidstone A229 Kerbside site. There appears to be a gradual reduction trend at this site since 2000 with the main contributor to the number of "Moderate" or above days resulting from PM10 concentrations was the first year since 2009 that Moderate or above days were recorded for NO2 at the site. The number of "Moderate" or above days since 2000 at Maidstone Rural is shown in Figure 12 (on the next page). As expected from a rural site ozone concentrations cause the greatest number of days of concentrations that are "Moderate" or above in most years. Although, in 2014, the highest number of Moderate or above days was from PM10. At Rochester Stoke, Figure 13, the main pollutants that result in days with "Moderate" concentrations are Ozone and PM2.5. There is no clear trend in the number of days from ozone concentrations but since 2011 there has been a marked increase in "Moderate" resulting from PM2.5 concentrations.

32 Kent and Medway Air Quality Monitoring Network 27 Figure 12 Pollutants that recorded concentrations of "Moderate" or above at Maidstone Rural between 2000 and 2014 Figure 13 Pollutants that recorded concentrations of "Moderate" or above at Rochester Stoke between 2000 and 2014

33 Kent and Medway Air Quality Monitoring Network 28 6 Trends in pollution levels, 1997 to 2014 In general, air quality is heavily influenced by prevailing meteorological conditions. Unless there are large changes in the sources then a long-term trend in pollution levels can be difficult to identify amongst short-term variation in pollutant concentrations. Settled conditions in winter, for instance, frequently lead to higher annual average NO2 or PM10 concentrations, whereas hot, sunny weather in summer gives higher ozone concentrations. To go some way towards smoothing out these short-term fluctuations and to identify any long-term trends, data can be presented as rolling annual means. This calculates an average each month for the previous 12-month period. This calculation is only deemed valid if there is at least 75 % data capture over the 12 months in question. This can result in some gaps in the rolling annual mean plots where periods of data loss have occurred. This section presents running annual means for the time period over which the monitoring network has operated. It is, of course, not possible to calculate running annual means for the first 12 months of operation of each site and so only those sites which were in operation before 1998 have rolling annual means for that year. 6.1 Carbon monoxide (CO) 2013 was the final full year of CO measurement being made in the KMAQMN with measurements only made at the Chatham Luton Background site. CO measurements continued at the site until March The running average mean is presented until this time. CO measurements at the Maidstone A229 Roadside and Canterbury Roadside sites ceased in November 2009 and December 2006 respectively. Carbon monoxide emissions are generally associated with combustion sources, particularly road transport. The movement towards vehicles with clean burn engines and catalytic converters has produced a significant drop in CO concentrations across the UK as a whole. The introduction of stopstart technology and electric vehicles may also start contributing to a future decrease in concentrations as this technology is taken up. AQS objective for CO, based on a running 8-hour mean, is 10 mgm -3. This air quality standard has not been exceeded in the Kent monitoring network over the last 14 years. The maximum concentration observed in 2014 was 1.6 mgm -3. Running mean concentrations at the Kent sites have generally been less than 10 % of this objective for almost the entire time series and this can be seen clearly in Figure 14. CO concentrations at the only remaining measurement site in the network appeared to have been showing steadily decreasing concentrations between 1998 and 2010 with some variation and increases in Higher running mean concentrations were observed in 2011, but these have decreased again during 2012, 2013 and Despite the increase during 2011, the measured concentrations of CO at the Chatham Luton Background site are still not of concern.

34 Kent and Medway Air Quality Monitoring Network 29 Figure 14 Trends in running annual mean CO concentrations

35 6.2 Nitrogen dioxide (NO2) Kent and Medway Air Quality Monitoring Network 30 The annual running mean data for nitrogen dioxide from each site are shown in Figure 15 to Figure 17. Due of the large number of stations, the measurement data have been split across three graphs. The roadside sites are split into rough geographic regions of east and west Kent whilst the background and rural sites are displayed on a third, separate graph so they can be compared. The data from Dover Docks are included in the graph displaying the eastern roadside sites because the concentrations are more comparable to those recorded at the roadside sites even though the site is now closed. Figure 15 and Figure 16 show that there was a mixed trend in concentrations of NO2 across Kent during 2014, as seen in other years. In Figure 16 all of the western roadside sites show an overall decrease in NO2 concentrations. The same trend is seen in some, but not all, of the eastern roadside sites shown in Figure 15. Thanet Ramsgate Roadside continued to remain relatively stable in concentration whilst the running annual mean at Swale Ospringe Roadside 2 continued to rise. Although due to poor data capture during the summer of 2014 the running annual mean for the whole year can t be calculated. In 2014, seven of the roadside sites exceeded the AQS objective of 40 µgm -3. Figure 17 shows that background concentrations continue to be well below the annual mean objective concentration and also show that the concentrations have remained relatively stable since the mid- 2000s, with an overall reduction at the majority of sites since Following spikes in 2013 of the running annual mean at Gravesham Industrial Background and Chatham Luton Background concentrations have continued to fall during Continued reductions in NO2 concentrations at several of the roadside sites and also at the majority of background sites could suggest that there is a general reduction in concentrations across the region. Figure 15 Trends in running annual mean NO2 concentrations - eastern roadside sites

36 Kent and Medway Air Quality Monitoring Network 31 Figure 16 Trends in running annual mean NO2 concentrations - western roadside sites Figure 17 Trends in annual mean NO2 concentrations - background and rural sites

37 6.3 Ozone (O3) Kent and Medway Air Quality Monitoring Network 32 Figure 18 shows the trends in running annual mean ozone concentrations since There are some observable short term trends in the rolling annual mean concentration of ozone at some sites. However during the 15-year period there is no discernible long term reduction or increase in concentrations. Figure 18 Trends in running annual mean ozone concentrations Sunlight plays a key role in the formation of low level ozone, so the highest annual mean concentrations tend to be recorded in years of long hot summers. This pattern is illustrated by the peaks in running annual means in 2003 and between 2006 and 2007 and the drops in running annual mean concentrations towards the end of 2007 and There is no longer term trend evident across the Ozone sites. 6.4 Fine particles (PM10 and PM2.5) Prior to 2010 there were two types of analysers employed to measure PM10 and PM2.5 in the KMAQMN - the Beta Attenuation Monitor (BAM) and the TEOM. Both require correction before comparison with AQS objectives; the BAM requires a correction factor of 0.83 to produce data comparable to the gravimetric reference method for PM10. As discussed in Section 2.3, data from TEOM monitors require correction using the King s College Volatile Correction Model (VCM) which corrects TEOM data using FDMS data from nearby sites. For the purpose of long-term analysis, however, there is limited historical FDMS data with which to correct old TEOM datasets. For this reason the data from the TEOM analysers presented in this section have been corrected by the 1.3 correction factor formerly used before the VCM became available, to allow for consistent trend comparison which is the purpose of this section of the report. In 2010 two of the TEOM analysers, at Chatham Roadside and Maidstone Rural sites, were upgraded with FDMS units. As this is a different measurement technique it is not viable to compare long term results from the two analyser types. Measurements from these sites and others that have been VCM corrected are shown in Figure 19. The sources of particulate matter (including PM10 and PM2.5) can vary between locations as particulate matter is frequently transported considerable distances in the atmosphere. Long-range transport is known to bring particulate matter to the UK from mainland Europe, and on occasions from even further afield e.g. from Saharan dust or large forest fires. Concentrations at a particular site therefore do not

38 Kent and Medway Air Quality Monitoring Network 33 only depend on nearby sources. For instance during periods with significant long-range transport of pollutants rural sites may record concentrations very close to those observed at urban background stations. Roadside sites can, however, have significantly enhanced concentrations due to a considerable contribution from local sources (vehicle emissions, tyre and brake dust, re-suspended particles, etc.). Figure 19 and Figure 21 show the trends in the running annual average PM10 concentrations at TEOM and BAM sites in the KMAQMN. It is apparent from a review of the figures that there are relatively high background and rural concentrations of PM10 across Kent. With a proportion of the particulate matter coming from more distant sources it can often be difficult to make significant reductions in ambient concentrations of particulate matter. Figure 19 Trends in running annual mean TEOM PM10 concentrations A correction factor of 1.3 is applied to allow comparison with historical data. FDMS data are unavailable for earlier data, so VCM correction cannot be applied across the entire time series. The annual mean VCM corrected data has however been presented in Figure 20. As highlighted in the previous annual report it is possible to correct TEOM data using Defra s Volatile Correction Model ( This has been done for sites that have been operating in recent years and where this is possible to correct. Annual mean concentrations have been displayed in Figure 19. From this visual assessment of the data there appears to be a potential shortterm decrease in PM10 concentrations. It should be noted that the TEOMs at the sites of Maidstone Rural, Rochester Stoke and Chatham Roadside have been upgraded and are now FDMS-TEOMs so correction is not required after the date they were installed.

39 Kent and Medway Air Quality Monitoring Network 34 Figure 20 Annual mean TEOM PM10 concentrations VCM corrected where required As might be expected the TEOM data continues to show that the contribution from traffic results in more elevated concentrations at the roadside sites compared to background sites. There isn t much that can be drawn from the above figure relating to trends however as additional data is collected from the sites trends may become more apparent. Figure 21 shows that the overall trends at sites with BAM analysers are similar to those observed at the sites with TEOM analysers with an increase in concentrations during This reverses a general downwards trend across all BAM sites since Figure 21 Trends in running annual mean BAM PM10 concentrations (0.83 correction factor applied)

40 Kent and Medway Air Quality Monitoring Network 35 Running annual mean concentrations for PM2.5 at Rochester Stoke and Chatham Centre Roadside are shown in Figure 22. Figure 22 Trends in running annual mean PM2.5 concentrations There is currently no recognised factor to apply to PM2.5 data derived from TEOM analysers to correct for the loss of volatile particles during the measurement process. This figure therefore presents uncorrected PM2.5 TEOM data. Concentrations had appeared to remain fairly constant at the Rochester Stoke site since 1999 to However the data available from 2011 to 2014 appears to indicate there has been an increase at this site. The Chatham Centre Roadside site did have higher PM2.5 concentration than the Rochester Stoke site, although this reversed in 2013, it continued during However, the dataset is too short to allow comment on long term trends at this site. 6.5 Sulphur Dioxide (SO2) The key sources of sulphur dioxide in Kent are the power stations and other industrial sites in the north of the county, and shipping activities in the vicinity of Folkestone and Dover. The shipping activity is thought only to affect the local concentrations. Figure 23 shows how trends at the sites in the north of the county have reduced over the measurement period, reflecting a reduction in emissions from the industrial sources. There was an exception noted at the Chatham Luton background site between 2006 and 2007 where concentrations increased. Since 2008 this site has seen a reduction in concentrations with some fluctuations. In 2014 the increase in concentrations at Rochester Stoke continued reversing the trend of declining concentrations up to 2012.

41 Kent and Medway Air Quality Monitoring Network 36 Figure 23 Trends in running annual mean SO2 concentrations

42 Kent and Medway Air Quality Monitoring Network 37 7 Diffusion tube results 7.1 Introduction In addition to the aforementioned automatic monitoring, most of the local authorities of Kent and Medway undertake indicative measurements of NO2 using diffusion tubes. Diffusion tubes are a type of passive sampler that absorbs the pollutant of concern (in this case nitrogen dioxide) directly from the ambient air for a period of days or weeks. They are then analysed in a laboratory, and the ambient concentration of NO2 (averaged over their exposure period) is calculated. Diffusion tubes provide a useful tool for investigating spatial variation in NO2 concentrations as they can be fixed unobtrusively to street furniture or buildings, are low in cost and do not require a power supply. This section presents a summary of each local authority s NO2 diffusion tube results for 2014 and, where applicable, a discussion of how NO2 concentrations (as measured by this method) have changed in recent years. Table 7 shows the total number of sites operated during part or all of 2014, by each authority. Where tubes were exposed in triplicate at a site, this is counted as one site even if the local authority uses different site identification numbers for the tubes. Table 7 NO2 diffusion tube sites in Kent and Medway, 2014 Local Authority Number of sites Comments Analytical laboratory used in 2014 (A) Ashford 17 3 sites started up, 4 closed down. ESG Didcot Canterbury 28 1 site started up, 1 closed down. ESG Didcot Dartford 50 3 sites started up, 1 closed down. Gradko International Dover 14 Counting the triplicate DV06, DV07 and DV08 as one site. ESG Didcot Gravesham 53 3 sites started up, none closed down. ESG Didcot Maidstone 72 - ESG Didcot Medway 23 - ESG Didcot Sevenoaks - Not covered by this report - Shepway 13 - ESG Didcot Swale 58 2 sites started up, 1 closed down. ESG Didcot Thanet 25 2 sites started up, 1 closed down. ESG Didcot Tonbridge and Malling 55 6 sites started up, none closed down. ESG Didcot Tunbridge Wells 24 1 site started up, none closed down. ESG Didcot (A) Note: all local authorities except Dartford have used tubes prepared and analysed by ESG Didcot (formerly Harwell Scientifics) since 2005, but prior to this various other analytical laboratories were used.

43 Kent and Medway Air Quality Monitoring Network Site classifications In years to 2011 inclusive, the diffusion tube sites have been classified according to the site classifications used in the Local Air Quality Management Technical Guidance (Table A1.4 of LAQM.TG(09)), available at These are: - Kerbside (0-1 m from the kerb of a busy road); - Roadside (1-5 m from the kerb of a busy road); - Urban background; - Urban centre; - Industrial - Suburban; - Rural; and - Other. Most sites in the Kent and Medway network are classified as either kerbside or roadside, with some urban background sites and a few suburban, rural and industrial. Kerbside sites might be expected to result in the highest annual mean NO2 concentrations. However, previous reports in this series have highlighted that this is not necessarily the case. Kerbside and roadside sites together record the highest annual mean NO2 concentrations: there is no clear distinction between these two categories in terms of NO2 concentration. The likely explanation is that some roads are busier than others: a roadside site associated with a busy road is likely to be exposed to a higher concentration of NO2 than a kerbside site beside a less busy road, despite being further from the kerb. Therefore, when considering the network as a whole, the distinction between kerbside and roadside has not been particularly useful. The automatic sites in the Kent and Medway network now use site classifications based upon those set out in the EU Air Quality Directive (2008/50/EC), available online at In this report, this system of classification has been extended to the diffusion tube sites. Sites classified as kerbside and roadside in previous reports in this series are now considered together as one category - urban traffic. The urban background, urban industrial and rural background sites are all assumed to meet the criteria of the corresponding Directive site categories urban background, industrial urban and background rural. Background rural sites are here referred to simply as rural for convenience. Some of the automatic sites names contain descriptors such as kerbside or background (for example Gravesham A2 Roadside ): these have not been changed as they are part of the site name. 7.3 Accuracy and bias adjustment In spite of their convenience and ease of use, diffusion tubes have certain limitations as they do not offer the same precision and accuracy provided by more expensive automatic methods, and are therefore only considered to be an indicative monitoring technique. Also, with a typical exposure period of days or weeks (one month is typical in this context) they are unsuitable for monitoring short-term averages (such as the 1-hour mean). In addition the accuracy of diffusion tubes may be affected by a number of sources of interference, both during exposure and at the analysis stage, which can cause them to exhibit so-called bias i.e. underread or (more commonly) over-read relative to the automatic analyser. Therefore, for the purpose of Local Air Quality Management, the accuracy of the diffusion tubes should be quantified by means of a co-location study, in which diffusion tubes are exposed at the same site as an automatic analyser throughout the duration of the survey. The ratio of the automatic analyser result to the diffusion tube result is used as a bias adjustment factor and applied to the annual means measured by the diffusion tubes at the other sites. It should be noted that diffusion tube accuracy can vary depending on the laboratory used to prepare and analyse the tubes and over varying periods of time, so bias adjustment factors are specific to a particular period. For the purposes of LAQM, bias adjustment factors are applied over the calendar year. A bias adjustment factor has therefore been applied to the diffusion tube annual means presented in this report. For diffusion tubes prepared and analysed by ESG Didcot, the adjustment factor used is This is a combined bias adjustment factor for 2014, downloadable from the Defra Local Air Quality

44 Kent and Medway Air Quality Monitoring Network 39 Management Support web page at (March 2015 version). The bias adjustment factor for ESG Didcot was based on 22 co-location studies carried out by Local Authorities in the UK, 6 of which were Authorities in Kent. All the Kent and Medway Local Authorities use ESG Didcot s tubes, except one. The exception is Dartford Borough Council, which uses tubes from Gradko International, prepared using a 20% solution of triethanolamine (TEA) in water. The combined bias adjustment factor for tubes of this type prepared and analysed by Gradko International for 2014 was 0.91, based on 24 co-location studies carried out by Local Authorities in the UK. Please note that this database of bias adjustment factors is regularly updated and there may be small changes to the bias adjustment factors at a later date. The bias adjustment factors used were correct at the time of writing. Bias adjustment factors for previous years were taken from the March 2014 version of the database, and may differ slightly from those used in previous reports in this series. Also, please note that although combined or national bias adjustment factors have been used in this report, it is possible that locally derived bias adjustment factors (based only on colocation studies within their area) might be used in other contexts. As an example, some Kent Local Authorities may select locally derived bias adjustment factors when preparing their Review and Assessment reports. 7.4 Diffusion tube results 2014 This section reports the results of each local authority s diffusion tube monitoring in For each authority, the following are shown. 1. Annual mean NO2 concentrations measured in 2014 at all diffusion tube sites, in the form of a bar chart. These bar charts illustrate the range of annual mean concentrations measured by each authority. Sites of different types are shown in different colours. Only sites with at least nine months valid data are shown as any less than this would not provide an accurate estimation of the annual mean. The appropriate bias adjustment factor has been applied to the annual means. 2. A comparison of monthly mean NO2 concentrations measured by diffusion tubes, against data recorded by co-located automatic analysers, where available. The NO2 diffusion tube data are not biasadjusted for this comparison. 3. The following sections also look at long-term changes in NO2 concentration, as measured by long-running sites. These are illustrated by time series charts of annual mean concentrations from In some cases it is possible to plot reliable annual means from earlier years. The time series charts are based on sub-sets of long-running sites in the various site categories: this is a more robust approach than including every site, because most local authorities have made changes to the composition of their networks over the years. Also included are the annual means from any automatic monitoring sites (shown as a dotted line), and any diffusion tube sites that are co-located with them. Combined bias adjustment factors (from the Defra database referred to in section 7.3) have been applied to the averaged annual means in these charts.

45 Kent and Medway Air Quality Monitoring Network Ashford Borough Council Figure 24 shows bias-adjusted annual mean NO2 concentrations measured at Ashford Borough Council diffusion tube sites during There were 16 sites in operation during the year. 15 sites achieved the minimum nine months data required for a valid annual mean. The annual means shown in this chart are bias-adjusted as explained in section 7.3. Figure 24 Annual mean NO2 at diffusion tube sites in Ashford, 2014 The majority of Ashford s sites are classified as urban traffic, being within 10 m of the kerb of a busy road. However, all of the sites recorded annual means within the AQS objective of 40 µgm -3. There are no longer any automatic monitoring sites in Ashford with which to co-locate diffusion tubes, since the closure of the former Ashford Background in Figure 25 shows how the annual means as measured at Ashford s diffusion tube sites have changed since 2001 (the earliest year for which bias adjustment factors were available). Bias adjustment factors assume Ashford used Kent Scientific Services from 2001 to 2003 and ESG Didcot (formerly trading as Harwell Scientifics) thereafter. The means for five long-running urban traffic sites, and three longrunning urban background sites, are shown. The bias-adjusted data appear to indicate that mean NO2 concentrations at urban background sites have decreased slightly since the early 2000s. However, for urban traffic sites there is no clear trend. More information on the bias adjustment factors used, and diffusion tube accuracy, have been presented in Section 7.3.

46 Kent and Medway Air Quality Monitoring Network 41 Figure 25 Time series of NO2 concentrations in Ashford (bias-adjusted)

47 Kent and Medway Air Quality Monitoring Network Canterbury City Council Figure 26 shows the annual mean NO2 concentrations measured at Canterbury City Council diffusion tube sites during Figure 26 Annual mean NO2 at diffusion tube sites in Canterbury, 2014 Canterbury operated 28 diffusion tube sites during 2014, including two which were co-located with automatic monitoring sites. The majority of Canterbury s sites are classified as urban traffic, with just one urban background site. Twelve sites recorded an annual mean in excess of the AQS objective of 40 µgm -3. Diffusion tubes are co-located (in triplicate) with the automatic analysers at the Canterbury urban background site (at Chaucer School) and the Canterbury Military Road site. Figure 27 and Figure 28 compare the monthly mean results from the diffusion tubes and automatic analysers at these two sites respectively.

48 Kent and Medway Air Quality Monitoring Network 43 Figure 27 Comparison of diffusion tubes and automatic analyser, Canterbury Urban background (Chaucer School), 2014 (no bias adjustment factor applied) Figure 28 Comparison of diffusion tubes and automatic analyser, Canterbury Military Road 2014 (no bias adjustment factor applied)

49 Kent and Medway Air Quality Monitoring Network 44 On average, the tubes over-estimated compared to the automatic analyser slightly at both Canterbury Background and Canterbury Military Road. Graphs such as these illustrate the necessity of bias adjustment. Figure 29 shows how the bias-adjusted annual means as measured by Canterbury s diffusion tube sites have changed since Earlier years are not shown because the prior to this year the number of sites was small. Twelve urban background sites have been in operation since 2006, and the mean NO2 concentration for this sub-set of long-running sites is plotted. This average has remained stable from 2006 to 2010, but appears to have decreased from 2010 to More information of the bias adjustment factors used and accuracy have been presented in Section 7.3. Canterbury now has only one urban background site: CA18 which is co-located with the Canterbury automatic monitoring site at Chaucer School. CA18 has been in operation long enough to represent trends: this site appears to show a slight downward trend since Data from the automatic analysers at Canterbury and Canterbury Military Road are shown as dotted lines, and the co-located diffusion tube sites are shown by solid lines of the same colour. There is agreement between the patterns shown by the automatic analysers and the diffusion tubes with which they are co-located. Figure 29 Time series of NO2 concentrations in Canterbury (diffusion tube data bias-adjusted)

50 DA53 DA07 DA18 DA54 DA56 DA89 DA86 DA85 DA17 DA70 DA83 DA79 DA90 DA63 DA75 DA68 DA48 DA60 DA25 DA21 DA24 DA78 DA38 DA81 DA50 DA49 DA87 DA80 DA01 DA72 DA10 DA41 DA69 DA94 DA39 DA35 DA34 DA95 DA44 DA62 DA16 DA61 DA20 DA05 DA22 DA84 DA43 DA14 Kent and Medway Air Quality Monitoring Network Dartford Borough Council Dartford Borough Council operated 50 diffusion tube sites during The tubes were analysed by Gradko International, and a combined bias adjustment factor of 0.91 has been applied to the annual means. Figure 30 shows the bias-adjusted annual mean NO2 concentrations measured during 2014 (two sites are not included because they measured less than nine valid monthly means in the year). Figure 30 Annual mean NO2 at diffusion tube sites in Dartford, Key: Green = Rural, Light blue = Urban Background, Red = Urban Traffic, Purple = Suburban 70.0 Annual Mean NO 2 Concentration (bias adjusted) µgm AQS Objective Dartford is closer to Greater London than most of the other Kent Boroughs and is relatively built-up, with many busy roads. Over half of the sites in Dartford exceeded the AQS objective of 40 µgm -3 for annual mean NO2 in The majority of these sites were urban traffic sites, but one urban background and one suburban site also exceeded the annual AQS objective. Dartford has three automatic NO2 monitoring sites Dartford Bean Interchange, Dartford St Clement s and Dartford Town Centre (all urban traffic). However, diffusion tubes are only co-located at one of these sites Dartford Bean Interchange. Figure 31 shows unadjusted diffusion tube and automatic analyser results from the Dartford Bean Interchange site. Unfortunately data capture at Dartford Bean Interchange was low during 2014, so limited data are available for comparison. However, in months where data were available from both the automatic monitoring station and the diffusion tubes, the diffusion tube results are higher than the monthly mean from the automatic analyser.

51 Kent and Medway Air Quality Monitoring Network 46 Figure 31 Comparison of diffusion tubes and automatic analyser, Dartford Bean Interchange 2014 (no bias adjustment factor applied) Figure 32 shows a time series of annual mean NO2 concentrations in Dartford. Because the size and composition of the network has been relatively stable over the past decade, and the laboratory used has not changed, this time series has been plotted back to 2001 (the earliest year for which an applicable bias adjustment factor is available). The urban traffic mean NO2 concentration is based on 11 long-running diffusion tube sites (DA01, DA05, DA09, DA14, DA16, DA17, DA20, DA21, DA22, DA23 and DA24). The graph also shows the mean NO2 concentrations based on measurements from the only three long-running urban background sites, DA07, DA18 and DA25. The diffusion tube data indicate a slight general decrease in ambient NO2 concentrations at all site types, from 2003 onwards. Also shown is the result from the Dartford Bean Interchange automatic monitoring site (the dotted line), and its co-located diffusion tube site DA05 (shown as a solid line of the same colour). The annual mean for 2014 (51 µgm -3 ) is shown despite low data capture of just 39% but should be treated as indicative only.

52 Kent and Medway Air Quality Monitoring Network 47 Figure 32 Time series of NO2 concentrations in Dartford (diffusion tube data bias-adjusted) Long-running UT 3 Long-running UB Dartford Bean Interchange DA05 (= Bean Interchange) 70 Annual Mean NO 2 Concentration (bias adjusted) µgm Bias-adjusted. All tubes from Gradko International More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

53 Kent and Medway Air Quality Monitoring Network Dover District Council Figure 33 shows the bias-adjusted annual mean NO2 concentrations measured at Dover District Council diffusion tube sites during Dover District Council operated 16 diffusion tube sites. Of these, all had at least nine months data capture and are included in the figure. Nine sites exceeded the AQS objective of 40 µgm-3. However, it was not necessarily the urban traffic sites that measured the highest concentrations: the site with the highest annual mean concentration in 2014 was a site within an air quality management area, DV-24 B Snargate. Figure 33 Annual mean NO2 at diffusion tube sites in Dover, 2014 The Dover Old Town Hall automatic monitoring site closed down at the beginning of Since then, no diffusion tube monitoring sites in Dover have been co-located with an automatic monitoring site. Figure 34 shows how the annual means, as measured by Dover s diffusion tube sites, have changed since 2005, based on a sub-set of eight urban traffic sites that have operated since 2005 or earlier. Years prior to 2005 are not shown, as site changes and changes of tube supplier mean that data for these earlier years are not comparable with more recent data. Urban background sites are not included, as there are none which have been in operation consistently for at least five years. The average from the eight long-running sites indicates that NO2 concentrations appear to have remained stable in Dover over recent years. However, measured concentrations for the diffusion tube sites DV06-DV08 at the Old Town Hall appear indicate that NO2 concentrations at this particular location have increased since the automatic analyser was removed, and indeed have exceeded the AQS objective in 2013 and 2014.

54 Kent and Medway Air Quality Monitoring Network 49 Figure 34 Time series of mean NO2 concentrations in Dover (diffusion tube data bias-adjusted) 50 8 Long-running UT sites (from 2005) DV06-DV08 (= Old Town Hall) Old Town Hall Auto 45 Annual Mean NO 2 Concentration ( bias adjusted) µgm Diffusion Tubes from ESG. Bias-adjusted More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

55 Kent and Medway Air Quality Monitoring Network Gravesham Borough Council Figure 35 shows the annual mean NO2 concentrations measured by Gravesham Borough Council s diffusion tube sites. Gravesham operates a large number of sites there were 53 in operation during 2014 (counting co-located triplets as one site), of which 50 had at least nine months data. The majority of Gravesham s sites are urban traffic and most were within the Air Quality Strategy Objective for annual mean NO2 in Figure 35 Annual mean NO2 at diffusion tube sites in Gravesham, 2014 Figure 36 and Figure 37 show co-location results at Gravesham A2 Roadside and Gravesham Industrial respectively. Generally, the diffusion tube results reflected those of the automatic analyser, typically over-estimating slightly, as in previous years. The diffusion tubes over-estimated more at Gravesham A2 Roadside than at Gravesham Industrial.

56 Kent and Medway Air Quality Monitoring Network 51 Figure 36 Comparison of diffusion tubes and automatic analyser, Gravesham Roadside 2014 (no bias adjustment factor applied) Figure 37 Comparison of diffusion tubes and automatic analyser, Gravesham Industrial (Urban background) 2014 (no bias adjustment factor applied) Figure 38 shows how the bias-adjusted annual means as measured by Gravesham s diffusion tube sites have changed since The number of diffusion tube sites increased considerably in 2005, so

57 Kent and Medway Air Quality Monitoring Network 52 rather than base this time series graph on the mean of all sites, two sub-sets of long-running sites have been used. These are three urban traffic sites in operation since 2004 (GR08, GR13 and GR21), and five urban background sites in operation since 2006 (GR11, GR19, GR69, GR78 and GR72). Also shown is the average of 21 urban traffic sites, all operational from Data from the two automatic monitoring sites at which diffusion tubes are co-located are represented by dotted lines. The corresponding diffusion tube values are shown by solid lines of the same colour. The data shown indicate that annual mean NO2 concentrations measured at Gravesham s longestrunning sites have decreased. In particular, the Gravesham Roadside automatic site (and its co-located diffusion tube sites GR08) have decreased considerably in recent years, and have been below the AQS Objective since (The annual mean for 2008 at Gravesham Roadside has been included for consistency with previous years reports, despite only achieving 8 months data capture.) Figure 38 Time series of NO2 concentrations in Gravesham (diffusion tube data bias-adjusted) 60 3 Long-running UT sites (from 2001) 5 Long-running UB sites (from 2006) Gravesham Industrial GR19 = Gravesham Industrial Gravesham A2 Roadside GR08 = Gravesham Roadside 21 Long-running UT sites from 2004 Annual Mean NO 2 Concentration (bias adjusted) µgm Diffusion tube data bias-adjusted More information on the bias adjustment factors used, and diffusion tube accuracy, is given in section 7.3.

58 Kent and Medway Air Quality Monitoring Network Maidstone Borough Council Figure 39 shows the bias-adjusted annual mean NO2 concentrations measured at Maidstone Borough Council s diffusion tube sites during Maidstone operated a total of 72 sites during part or all of Thirty-one sites had at least nine months data in Figure 39 Annual mean NO2 at diffusion tube sites in Maidstone, Key: Green = Rural Background, Light blue = Urban Background, Red = Urban Traffic, Purple = Suburban AQS Objective Annual Mean NO 2 Concentration (bias adjusted) µgm Maid 06 Maid 45 Maid 50 Maid 77 Maid 18 Maid 83 Maid 69 Maid 79 Maid 12 Maid 76 Maid 78 Maid 89 Maid 11 Maid 22 Maid 84 Maid 10 Maid 85 Maid 71 Maid 93 Maid 20 Maid 66 Maid 87 Maid 75 Maid 57 Maid 29 Maid 56 Maid 74 Maid 92 Maid 63 Maid 26 Maid 90 Maid 21 Maid 86 Maid 41 Maid 49 Maid 44 Maid 03 Maid 51 Maid 82 Maid 80 Maid 27 Maid 52 Maid 70 Maid 53 Only eight of Maidstone s diffusion tube sites measured annual means greater than the AQS objective of 40 µgm -3, with the highest value of 47 µgm -3 measured at Maid 53 (located at The Pilot pub, beside a busy major road). Figure 40 and Figure 41 show unadjusted co-location results at Maidstone A229 Kerbside (near the kerb of the A229 at the Maidstone Bridge gyratory), and Maidstone Rural (near the County Showground at Scragged Oak Road, Detling), respectively. At Maidstone Rural, both automatic and diffusion tube results show a strong seasonal pattern, being higher in the winter than the summer, with the exception of Maid 06 tube 1 which peaks in April. This pattern is less evident at Maidstone A229 Kerbside, where traffic is the main source of NO2: this source remains relatively constant throughout the year.

59 Kent and Medway Air Quality Monitoring Network 54 Figure 40 Comparison of diffusion tubes and automatic analyser, Maidstone A229 Kerbside 2014 (no bias adjustment factor applied) Figure 41 Comparison of diffusion tubes and automatic analyser, Maidstone Rural 2014 (no bias adjustment factor applied) Figure 42 shows how the annual mean NO2 concentrations have changed since 2005 at Maidstone s two automatic monitoring sites and their co-located diffusion tube sites (bias-adjusted). Because there were gaps in the dataset for earlier years, and a major reorganisation of the sites in 2008, only these

60 Kent and Medway Air Quality Monitoring Network 55 two long-running sites are shown for years 2005 onwards. However, last year it was possible to add the mean of a sub-set of 13 urban traffic sites, all of which have been operating for six years, since the reorganisation in The graph appears to show no clear trends in NO2 concentrations at Maidstone A229 Kerbside and Maid 03. The mean of 13 urban traffic sites in operation since 2008 shows a similar pattern. There is, however, some indication of a slight decrease at Maidstone Rural and Maid 06. Figure 42 Time series of NO2 concentrations at long-running and co-located sites in Maidstone (diffusion tube data bias-adjusted) 60 Maidstone A229 Kerbside Maid 03 (= Maidstone Kerbside) Maidstone Rural Maid 06 (= Maidstone Rural) 13 Long-running UT sites (since 2008) 50 Annual Mean NO 2 Concentration (bias adjusted) µgm Diffusion tube data bias-adjusted More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

61 Kent and Medway Air Quality Monitoring Network Medway Council Figure 43 shows the annual mean NO2 concentrations measured at Medway Council s diffusion tube sites during Medway operated 23 sites during 2014: all achieved at least nine months valid data. The majority of Medway's sites are urban traffic. Figure 43 Annual mean NO2 at diffusion tube sites in Medway, 2014 Ten of Medway s sites exceeded the AQS objective of 40 µgm -3 in 2014 (a similar proportion to that recorded in 2012 and 2013). Medway Council operated two automatic NO2 monitoring sites during 2014: Chatham Roadside and Rochester Stoke Rural. Diffusion tubes were co-located at each one (in triplicate). Figure 44 and Figure 45 show co-location results from Chatham Roadside and Rochester Stoke respectively. At Chatham Roadside the diffusion tubes typically exhibited positive bias with respect to the automatic analyser: however, lower results were obtained from two tubes in June, and one in November. The low result from tube 2 in November (circled in orange) appears to be an outlier and is probably a faulty tube result. At the rural Rochester Stoke site the diffusion tubes also typically gave higher concentrations than the automatic analyser: though again the June tubes exhibited less positive bias than those in other months. This dip in tube bias during June is also evident in the co-located tube results for two other sites operated by different Local Authorities - Gravesham Industrial and Swale St Pauls. This may be simply coincidence or could indicate an anomaly with the preparation or analysis of the tubes in this month. The tube 3 result for December at Rochester Stoke appears to be a high outlier.

62 Kent and Medway Air Quality Monitoring Network 57 Figure 44 Comparison of diffusion tubes and automatic analyser, Chatham Roadside 2014 (no bias adjustment factor applied) Figure 45 Comparison of diffusion tubes and automatic analyser, Rochester Stoke (Rural) 2014 (no bias adjustment factor applied) Medway s sites were substantially re-organised at the start of 2007, and none remain in their previous locations. Many were moved only a short distance - for example to the nearest building façade but this is a significant change in the case of an urban traffic site. Figure 46 shows how bias-adjusted

63 Kent and Medway Air Quality Monitoring Network 58 diffusion tube annual means have changed since 2007, based on a subset of 17 sites, all urban traffic, that have been in operation since Also shown are annual means for the three automatic monitoring sites. There appears to be a slight decrease since Figure 46 Time series of NO2 concentrations in Medway (diffusion tube data bias-adjusted) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section Sevenoaks District Council Sevenoaks District Council is not a member of the Kent and Medway Air Quality Monitoring Network. Please contact the local authority directly for information on local air quality, or alternatively see the London Air Quality Network website at

64 Kent and Medway Air Quality Monitoring Network Shepway District Council Shepway District Council exposed diffusion tubes at 13 sites during Twelve sites had at least nine months data, and these are included in Figure 47. Figure 47 shows the annual means at the sites, all of which were within the annual mean AQS objective of 40 µgm -3. Please note, the site numbers used here are those used on the Kent and Medway air quality website: different site numbers are used in Shepway s progress reports. Figure 47 Annual mean NO2 at diffusion tube sites in Shepway, 2014 Shepway District Council does not monitor NO2 using automatic methods at any of the diffusion tube sites, so there are no co-located sites at which to compare the two methods. Shepway s earliest available diffusion tube data are from 2008, so 2014 is the second year in which has been meaningful to look for possible trends. These are shown in Figure 48. Until 2013 there was a steady downward trend indicated for urban traffic diffusion tube concentrations. Urban traffic diffusion tubes have shown a slight increase in Urban background concentrations have decreased gradually since 2008.

65 Kent and Medway Air Quality Monitoring Network 60 Figure 48 Time series of NO2 concentrations in Shepway (diffusion tube data bias-adjusted) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

66 Kent and Medway Air Quality Monitoring Network Swale Borough Council Figure 49 shows the adjusted annual mean NO2 concentrations measured at Swale Borough Council diffusion tube sites during Swale had 57 sites in operation during part or all of Two new sites started up, and one closed down, during the year. Forty-eight sites had at least nine months data, and these are included in Figure 49. Figure 49 Annual mean NO2 at diffusion tube sites in Swale, 2014 Most Swale sites are designated as urban traffic. Fifteen sites exceeded the AQS Objective of 40 µg m -3 in Swale Borough Council operated four automatic monitoring sites during 2014: Swale Ospringe Roadside 2 (which has been in operation for a number of years, and is on the opposite side of the same street as the former Swale Ospringe Roadside site), Swale Newington 3, Swale Canterbury Road and Swale St Paul s (new site). Figure 50, Figure 51, Figure 52 and Figure 53 show monthly diffusion tube and automatic analyser results at these four sites respectively. At Swale Ospringe, the automatic analyser s data capture was relatively poor, with data missing throughout April to September. It has therefore not been possible to reliably compare the two techniques at this site. At Swale Newington 3 and Swale Canterbury Road, numerous diffusion tube results were missing or rejected during the year. Only at Swale St Pauls was there good data capture from both the diffusion tubes and the automatic analyser. At this site, the diffusion tubes typically over-estimated compared to the automatic analyser.

67 Kent and Medway Air Quality Monitoring Network 62 Figure 50 Comparison of diffusion tubes and automatic analyser, Swale Ospringe Roadside 2, 2014 (no bias adjustment factor applied) Figure 51 Comparison of diffusion tubes and automatic analyser, Swale Newington (no bias adjustment factor applied)

68 Kent and Medway Air Quality Monitoring Network 63 Figure 52 Comparison of diffusion tubes and automatic analyser, Swale Canterbury Road 2014 (no bias adjustment factor applied) Figure 53 Comparison of diffusion tubes and automatic analyser, Swale St Paul s 2014 (no bias adjustment factor applied) Figure 54 shows how annual mean NO2 concentrations have changed since 2005 (the year in which the majority of Swale s diffusion tube sites started operation), at the four automatic monitoring sites,

69 Kent and Medway Air Quality Monitoring Network 64 their co-located diffusion tube sites, and a sub-set of 11 long-running urban traffic diffusion tube sites in Swale that have all been in operation since 2006 or earlier. The average NO2 concentration for the sub-set of long-running urban traffic sites shows no clear increasing or decreasing trend overall between 2006 and As observed in previous years, the automatic monitoring sites also show no clear trends. Figure 54 Time series of NO2 concentrations in Swale (diffusion tube data bias-adjusted) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

70 Kent and Medway Air Quality Monitoring Network Thanet District Council Figure 55 shows the bias-adjusted annual mean NO2 concentrations measured at Thanet District Council s diffusion tube sites during There were 24 sites, 22 of which achieved at least nine months data capture. Triplicate tubes were used at four sites. Figure 55 Annual mean NO2 at diffusion tube sites in Thanet, 2014 The majority of Thanet s sites are urban traffic, but (as in previous years) very few Thanet sites exceeded the AQS objective of 40 µgm -3. Highest concentrations were measured at the triplicate sites of TH13, TH46 & TN47 at The Square, Birchington and at TH70, TH71 & TH72 on the High Street, St Lawrence. These sites have consistently shown the highest concentrations throughout years 2008 to Figure 56 and Figure 57 show diffusion tube co-location results at two Thanet automatic NO2 monitoring sites Thanet Airport (urban background) and Thanet Ramsgate Roadside respectively. (Diffusion tubes are also exposed close to the Thanet Birchington automatic site but are approximately 1 m from the kerb, whereas the automatic analyser inlet is 4 m from the kerb. This is therefore not considered to be a true co-location.) Diffusion tubes were not co-located at the fourth automatic monitoring site, Thanet Margate, the site was discontinued in March At both the co-located sites, the diffusion tubes typically gave results comparable with the monthly means from the automatic analyser. In the case of Thanet Ramsgate Roadside, one of the diffusion tubes (tube 3) gave high results compared with the other two (and with the automatic analyser) in September and October These results (circled in orange) are suspected to be spurious. Also suspicious are the December 2014 tube results which show unusually poor precision.

71 Kent and Medway Air Quality Monitoring Network 66 Figure 56 Comparison of diffusion tubes and automatic analyser, Thanet Airport 2014 (no bias adjustment factor applied) Figure 57 Comparison of diffusion tubes and automatic analyser, Thanet Ramsgate Roadside 2014 (no bias adjustment factor applied)

72 Kent and Medway Air Quality Monitoring Network 67 Figure 58 shows a time series chart of mean concentrations. It includes means for all the automatic monitoring sites and the diffusion tube sites co-located with them (including those near Thanet Birchington Roadside). Also shown are the mean of a sub-set of 12 long-running urban traffic sites in operation since 2005 or earlier and the mean of a sub-set of five long-running urban background sites in operation since the same year. The diffusion tube data have been bias-adjusted using the combined national bias adjustment factor. The diffusion tube data do not show any clear trend in NO2 concentration. Similarly, the long-running automatic sites (Thanet Airport, Thanet Margate Background and Thanet Ramsgate Roadside) show no clear upward or downward trends. Figure 58 Time series of NO2 concentrations in Thanet (diffusion tube data bias adjusted) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

73 Kent and Medway Air Quality Monitoring Network Tonbridge and Malling Borough Council Figure 59 shows the bias-adjusted annual mean NO2 concentrations measured by Tonbridge and Malling Borough Council during There were 49 diffusion tube sites in operation during Six sites were created during With the exception of TN97 at Shipbourne Road, all of the sites achieved the necessary nine months of valid data and are shown in the chart. Figure 59 Annual mean NO2 at diffusion tube sites in Tonbridge and Malling, 2014 The majority of the sites in this borough are urban traffic, with three urban background sites (TN18, TN95 and TN10). Seven sites exceeded the AQS annual mean objective of 40 µgm -3. The highest annual mean concentration was measured at the triplicate site TN42, TN76, TN77 at Tonbridge Road, Wateringbury. This site has consistently measured the highest annual mean in the district since Tonbridge and Malling has one automatic monitoring site: Tonbridge Roadside 2 (ZT5). However, diffusion tubes are not co-located with the automatic analyser, because the position of the inlet makes it difficult to change the tubes easily and safely. Therefore, a comparison of monthly means measured by the two methods cannot be included here. Figure 60 is a time series chart indicating how annual mean NO2 concentrations at Tonbridge and Malling s monitoring sites have changed since The average for urban traffic sites is represented by a sub-set of seven sites, all of which have operated since 2005 or earlier. These are; TN33, the colocated triplicate TN42, TN76 and TN77 (given separate numbers but one single site), TN43, TN44, the triplicate TN45, TN74, TN75 (again, one single site), TN47 and TN49 (the latter now part of a triplicate). The diffusion tube data have been bias-adjusted using the combined national bias adjustment factors. Also included is the annual mean NO2 concentration at the automatic Tonbridge Roadside 2 site, though no diffusion tubes are co-located with it, for the reasons specified above. No clear upward or downward trends are evident.

74 Kent and Medway Air Quality Monitoring Network 69 Figure 60 Time series of NO2 concentrations at long-running sites in Tonbridge and Malling (diffusion tube data bias-adjusted) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

75 Kent and Medway Air Quality Monitoring Network Tunbridge Wells Borough Council Figure 61 shows the bias-adjusted annual mean NO2 concentrations measured at Tunbridge Wells Borough Council diffusion tube sites during One new site was introduced at the start of 2014 at Goarse Road. There were 24 sites in operation during 2014, with 23 sites achieving at least 9 months of data capture. Figure 61 Annual mean NO2 at diffusion tube sites in Tunbridge Wells, 2014 The majority of Tunbridge Wells sites are urban traffic. Six of the sites (all urban traffic) exceeded the AQS annual mean objective of 40 µgm -3 in The three urban background sites were all well below the objective. Tunbridge Wells has one automatic monitoring site, Tunbridge Wells Roadside (on the A26 St John s Road); this has diffusion tubes co-located with it. Figure 62 shows a comparison of unadjusted monthly mean concentrations for 2014, as measured by the diffusion tubes and the automatic analyser. The diffusion tubes show positive bias with respect to the automatic analyser, as in previous years.

76 Kent and Medway Air Quality Monitoring Network 71 Figure 62 Comparison of diffusion tubes and automatic analyser, Tunbridge Wells A26 Roadside 2014 (no bias adjustment factor applied) Tunbridge Wells has a number of long-running sites, and it is possible to plot a time series from 2001: see Figure 63. Long-term changes at urban traffic sites are represented by a sub-set of eight sites which have been running since 2001 or earlier. Urban background trends are represented by a sub-set of three such sites which have also been in operation since 2001 or earlier. Combined national bias adjustment factors have been applied for each year. The figure also shows the annual means from two automatic monitoring sites, and the (bias-adjusted) diffusion tube results from site TW34 which is colocated with Tunbridge Wells A26 Roadside. There are no clear and consistent trends at the diffusion tube sites, though there is a peak in 2010 which is known to have been a high year for NO2.

77 Kent and Medway Air Quality Monitoring Network 72 Figure 63 Time series of NO2 concentrations in Tunbridge Wells (bias adjustment factor applied to diffusion tube data) More information on the bias adjustment factors used, and diffusion tube accuracy, has been presented in Section 7.3.

78 8 Review and assessment update 8.1 Ashford Borough Council Kent and Medway Air Quality Monitoring Network 73 Ashford Borough Council completed and submitted the Updating and Screening Assessment to Defra in April The diffusion tube network is unchanged and demonstrates compliance with the annual objective. The Updating and Screening Assessment has not identified any significant changes in emissions sources within the Ashford district area. There have been no new relevant industrial installations and no new significant commercial, domestic or fugitive sources of emissions. 8.2 Canterbury City Council In 2014 the Council completed its latest Air Quality Progress Report, which concluded that there were no further exceedences outside of the current AQMA. Diffusion tube monitoring for 2013 demonstrates a need to retain the current Air Quality Management Area. One diffusion tube site outside of the AQMA, at Herne Street, indicates an exceedence of the nitrogen dioxide annual mean objective during However, the location of the monitoring site is thought to be contributing to higher recorded concentrations of nitrogen dioxide in this location. New monitoring carried out during 2013 appears to support this hypothesis. The report concludes that additional diffusion tube monitoring is required in Herne Street, to more thoroughly investigate the levels of nitrogen dioxide there. The Council has also identified the need to review its current Air Quality Action Plan, given the expanded size of the AQMA it is now out of date. This is likely to take place following the review of other key strategies which will feed directly into the action plan. Since the air quality action plan was formally adopted by the Council, an expanded AQMA covering a number of the key routes in and out of the city centre has been declared. For this reason it is now appropriate to review the air quality action plan, so it better reflects the expanded AMQA, takes into consideration new evidence from the vehicle emissions study carried out in 2012, and adopts examples of best practice. This review will be informed by a number of key council strategies/policies, which include the Corporate Plan, Local Plan, Transport Strategy, and Environment Strategy, some of which are in various stages of production/review. This should provide much better links between these council policies and the measures in the new action plan. At the time of writing, the Corporate Plan and Environment Strategy have been adopted. However, work on the draft Local Plan and draft Transport Strategy are ongoing. 8.3 Dartford Borough Council Diffusion tube monitoring in 2014 again showed an upward trend in Nitrogen dioxide levels at some roadside locations, in particularly those in the proximity of the A282 tunnel approach road. A total of 30 monitoring locations recorded levels in excess of the annual mean objective, of which five are outside of existing AQMAs. These areas will be looked at further as part of the 2015 updating and screening assessment. Background monitoring levels have shown a decrease from previous years. The three Dartford continuous analysers suffered performance and reliability issues during 2014 and as such data capture rates were poor for the three sites, and as such the results should be treated with caution. Increased annual mean nitrogen dioxide levels were recorded at Greenhithe and Bean monitoring station, the Town Centre site recorded a decrease. The 200 μgm -3 Hourly mean limit was breached on an increased number of occasions during 2014 compared to the previous year. PM10 levels remained low at these sites. These three continuous analysers underwent an overhaul in January 2015 to improve data capture for the forthcoming year.

79 Kent and Medway Air Quality Monitoring Network Dover District Council Dover Council completed an Updating Screening Assessment recently which reviewed new monitoring data, which showed that exceedences of nitrogen dioxide continue to occur in Dover A20 Trunk Road AQMA and High Street/Ladywell AQMA where there is relevant exposure. The review of new diffusion tube monitoring data has identified five locations where the annual mean NO2 objective was exceeded in 2014, all within the existing AQMA. The Council undertakes monitoring at two sites located outside the AQMA which have been below the NO2 annual mean objective for a number of years. Concentrations at most sites showed a decrease in 2014 when compared to the previous year. Dover District Council has identified one biomass CHP installation which was granted planning permission in 2013 (and which may have an impact on local air quality): Biomass CHP plant at Discovery Park industrial estate: Kent Renewable Energy Partnership, Discovery Park, Ramsgate Road, Kent, CT13 9ND (National Grid reference: TR ). Planning application DOV/13/00701, environmental permit no. DDC/BIO/299/P1. An air quality assessment undertaken for this installation used ADMS 5 dispersion model to predict pollutant concentrations during the boiler operation phase. The predicted concentrations for both NO2 and PM10 were forecast to be well below the relevant objectives at the identified sensitive human receptor locations. The Council has identified two schemes which may have a potential to impact local air quality on the A20 and the surrounding road network. The Traffic Management Improvement works at the Eastern Docks involving the construction of a holding facility for freight vehicles and the installation of a VSM system are expected to have a beneficial effect on traffic approaching the Eastern Docks on the A20 (AQMA). Independent of this the recent introduction of new border controls at the port has been observed to cause increased HGV queuing on the A20. If the increased HGV queuing continues, it is recommended that additional diffusion tube monitoring sites are installed in the residential area close to the A20 in Aycliffe as this could have an impact on NO2 levels Conclusions of the most recent report include:- Proposed actions arising from the 2015 Updating and Screening Assessment are as follows: Continue NO2 diffusion tube and continuous monitoring in the district to identify future changes in pollutant concentrations; Consider expanding the monitoring network to include more sites outside the AQMAs; Proceed to a Progress Report in Gravesham Borough Council Updated monitoring in Gravesham in 2014 has identified one location outside of existing seven Air Quality Management Areas (AQMAs) where there has been an exceedence of the annual mean NO2 objective: GR119 Woodville Place, Gravesend. Although the site is not considered to be currently representative of relevant exposure at present (the primary reason for establishing the monitoring site was in advance of the change of use of the adjacent premises to residential), it is considered representative of the wider pollutant concentrations in the surrounding locale with relevant residential exposure on Wrotham Road (A227) between Zion Place and Woodville Place, where slow moving traffic passing close to property façades is expected to have a significant impact on pollutant concentrations. Therefore the Council has proceeded to a Detailed Assessment for the area with relevant residential exposure in the immediate vicinity of the exceeding site. The Council has deployed additional diffusion tubes at the Wrotham Road/Woodville Place junction and on Wrotham Road between Woodville Place and Zion Place, where concentrations are expected to exceed the annual mean objective for NO2. Updated diffusion tube monitoring also showed that six sites have exceeded the annual mean objective for NO2 within the existing AQMAs in Concentrations have shown a decrease at most sites within and outside of the AQMAs from 2013 to Continuous monitoring for NO2 and PM10 showed that the air quality objectives were met at both monitoring locations, with both NO2 and PM10 concentrations

80 Kent and Medway Air Quality Monitoring Network 75 exhibiting a decrease from the previous year at both monitoring sites. This reduction is due to the original sources of the pollution having either been removed or relocated further away from the residential areas where the continuous monitors are located. The council has introduced several new nitrogen dioxide monitoring sites specifically to monitor baseline levels of nitrogen dioxide in the area of the new Rathmore Road link in the town centre to be built in 2016/17. The monitoring network now comprising of 58 tube locations across the borough including 3 background sites. Three biomass installations are located within three schools in the Borough. A screening assessment undertaken for each of the installations found that the impacts on local air quality of two of the three installations are not significant. Regarding the third installation, the St. John s Catholic School boiler, it was not possible to screen out its impact on the local PM10 concentrations using the available emissions data. The council will therefore seek to collate additional information for the St. John s Catholic School boiler in order to undertake a further screening assessment for this installation using the ADMS-Screen screening model. As solid fuel burning in domestic properties may have the potential to increase PM10 levels at relevant locations, a screening assessment was undertaken to determine the risk of exceedence of 24-hr mean objective for PM10 in the urban area north of the A2 trunk road. It has been found that there is no risk of PM10 emissions from domestic properties burning solid fuel giving rise to an exceedence of the objective. The emissions calculated for the selected area were well below the threshold for exceedence. The council is working through the planning process to improve the air quality in the borough and to limit the adverse impacts on air quality of any new major development on the residents and visitors to the borough e.g. the new crematorium, London Paramount, Rathmore Road link, large housing developments etc. 8.6 Maidstone Borough Council There continues to be six known areas of annual NO2 exceedance around the Maidstone urban area, which are incorporated into one urban wide AQMA. A detailed quantification study (2013, amended 2014) of the 2010 Maidstone Air Quality Action Plan (MAQAP) has shown that the measures included in the MAQAP will not be sufficient to meet the air quality objective by A low emission scheme feasibility study to identify innovative & new approaches to reducing the emissions in the Borough was completed in May As part of this a screening assessment was carried out which re-ran source apportionment work and emission assessments and brought out some key information. [For example, if the Council were to ban all HDVs from the Wheatsheaf junction of A274 & A229, exceedance of the annual NO2 in this hotspot would still occur, because 25% of emissions in the area are from diesel cars and LGVs. This means that the car make up of the local Maidstone fleet is important, so just bus and HGV targeting alone will not be effective in controlling air quality exceedances here.] The resulting document was entitled Working towards a Low Emission Strategy and concluded that the Council s strategy for dealing with Air Quality problems within the borough should be a more generic Low Emission Strategy. The document provides evidence (quantified, where possible) to enable decision makers to take more account of the emission impacts that their decisions make; and provides evidence of how an emissions reduction approach can be of benefit to not only the environment but also to the health of our local communities and the local economy. The draft Local Plan includes an air quality specific policy and neighbourhood plans in key hotspot areas include their own air quality policies. The draft Low Emission Strategy has a specific section on supporting emission reduction through the planning process and will support Maidstone s ambition to continue to grow and develop in a sustainable way. The Council has been working closely on a low emissions bus project with the neighbouring Tonbridge & Malling District Council, Kent County Council and Arriva bus operator. After some delays the project is nearly ready to enter the procurement stage and up to 10 EU3 Volvo B7 buses are to be retrofitted along the A20 route which crosses between the two districts. This complements the 11 hybrid buses along the same route. The route has become known as the Greenway and on-board monitoring

81 Kent and Medway Air Quality Monitoring Network 76 combined with ambient monitoring in the Maidstone high Street is planned so that the benefits of this 20% fleet improvement project will be evaluated. KCC have installed two electric vehicle charging points in publically accessible car parks in the Borough (in the vicinity of Maidstone Leisure Centre & Session House), which will enable the council to improve their own fleet and support the public in taking up the ULEV option. A double charging point is also shortly to be installed at the Mall. We have continued our financial support of KM Charities walk to school scheme and hosted a Green Champions event, led by the Environment portfolio holder and attended by local school councils. We hope to continue our support of the charity which for several years has annually precipitated removal of over 200,000 car trips across Kent & Medway roads at peak traffic hours. We are actively supporting the regional Kent & Medway Air Quality Partnership and the ongoing work of its Health sub-group. The monitoring network has been maintained, but due to cut-backs and faults with ageing equipment Ozone and Sulphur dioxide, monitoring of these pollutants at Maidstone Rural Air Quality Station ceased in The search for suitable sites and electricity supplies for two temporary continuous monitors in order to provide extra information around the high street area and Upper Stone Street continues. The Updating & Screening Assessment report for 2014 is currently in the process of being put together. The Maidstone Air Quality Management Area is currently being reviewed and it is envisaged that the 2010 air quality action plan will be refreshed in 2015/16 in order to take account of internal changes both within Maidstone Borough Council and the Highways Authority (Kent County Council) and the new information developed since Medway Council Medway s first AQMA was declared in 2004 for the pollutant nitrogen dioxide and comprised six separate locations in the urban part of the district. An Air Quality Action Plan was produced in July 2005 and annual reports have been published since then. Exceedances of the annual mean NO2 objective at four sites outside of the existing AQMA were noted within the 2007 progress report, which meant that a Detailed Assessment (DA) was required for those areas. Work on the DA started at the end of Medway published its third Updating and Screening Assessment in April It concluded that there was a requirement to undertake a DA for annual average NO2. Medway s DA was published in August 2009 and recommended extending the current AQMA declaration and declaring new areas as AQMAs. A twelve-week consultation with statutory consultees on the proposed revocation of the first AQMA and replacement with a new AQMA ended on 26th March Medway Council declared the following three new AQMAs on 6th August A large central Medway AQMA which includes the existing AQMAs of Frindsbury Road, Cuxton Road, Strood Centre, Rochester Centre and Chatham Centre but also includes the new areas of Luton Road, Chatham Hill and High Street, Chatham A smaller AQMA along High Street, Rainham A smaller AQMA at Pier Road, Gillingham Subsequently, a Further Assessment (FA) was published in July 2011, the monitoring and dispersion modelling carried out to support the FA indicated that exceedances of the NO2 annual mean are still prevalent throughout Medway s three AQMAs and that the AQMAs are appropriate and do not require revoking or amendment. Medway is currently in the process of producing an action plan. Medway published its fifth Updating and Screening Assessment in May It concluded that there were no significantly new or substantially changed sources that required a DA. Major regeneration continues within Medway, including the extensive waterfront developments at Rochester and Gillingham. A number of planning applications for housing and employment developments were approved in The Environmental Health team continues to work closely with internal planners and transport planners on air quality issues related to transport and land use planning. Medway Council s Local Transport Plan 3 came into effect on 1st April 2011 and runs until The document sets out a programme of works over the fifteen-year period of the plan and includes measures that impact on air quality. The Environmental Health team were consulted during the development of

82 Kent and Medway Air Quality Monitoring Network 77 the plan. Some of the key features during 2014 include improvements to the traffic management system through Medway to improve the free flow of traffic. The traffic operations room (TOR) is now part of the traffic management/network management area. It houses the UTMC common database including a public transport data management facility; variable message signage control and traffic cameras. The TOR provides the opportunity to manage and control the highway network, and also provide response to incidents which also produce congestion. Medway has also produce the latest Medway Network Management Plan in draft which takes further the network management duty in managing the network and reducing congestion 8.8 Shepway District Council Shepway DC has not been required to declare an Air Quality Management Area and our consultants are currently completing Shepway s 2014 Update and Screening Assessment. Initial findings would suggests it supports this decision. At the start of 2013 additional diffusion tube monitoring sites, located in Horn Street, Lydd and Hawkinge had been installed. Initial findings indicate they are within the exceedance levels. Shepway s 2014 Update and Screening Assessment will be submitted to DEFRA in due course. 8.9 Swale Borough Council Swale retains four Air Quality Management Areas and four continuous monitoring stations at Newington, St Pauls Sittingbourne, Canterbury Road Sittingbourne, and Ospringe. In addition there were 72 Nitrogen Dioxide Diffusion tubes in use. There was a few instances of breakdowns during the year which have had a result in a reduced data capture rate for some stations, e.g. there was a major air conditioning issue at the Ospringe station which was subsequently resolved. The 2014 Annual Progress Report concluded the following actions were necessary for 2015: Continue with NO2 diffusion tube and continuous monitoring in the Borough to identify future changes in pollutant concentrations; Continue monitoring at The Mount for the tube location SW95 in Ospringe Street, Faversham; Proceed to a Detailed Assessment for the Teynham area; Gather information on the capacity of the biomass installation installed at Rhode Court Barn, Selling Road, Selling, Faversham; and Proceed to the 2015 Updating and Screening Assessment. The results of the Teynham detailed assessment and the 2015 Update and Screening Assessment are still to be received. If the detailed assessment concludes that there are levels of Nitrogen Dioxide near to or exceeding the limit value, consideration will be given as to whether there should be another AQMA declared, but that decision will be made at a later date. There have been two successful steering group meetings in the Newington and East Street AQMA areas; more are planned and there are also plans to include the other two AQMAs. Fleet Operators have joined the Ecostars Fleet Recognition Scheme and it is the intention to enlist the support of as many members as possible for Another project will be to promote other air qualitybased initiatives including the Kent Smarter Travel Challenge. Swale also remains active in the Walk to School initiative being coordinated jointly by the KM group and Kent County Council Public Health team. Swale has been a member of this group for longer than any other authority in Kent, since the scheme was introduced. Swale have been involved in the Kent Smarter Travel Challenge which promoted sustainable business travel across the whole of Kent.

83 8.10 Thanet District Council Kent and Medway Air Quality Monitoring Network 78 The Annual Progress Report 2014 concluded that the junction of Boundary Road and Hereson Road Ramsgate had exceeded the annual objective for nitrogen dioxide. This brings the number of exceedence areas within Thanet to three. The new exceedence area is within the designated urbanwide AQMA so no further assessment is deemed necessary given that the measures included within the Action Plan (2013) already apply. We continue to monitor real time pollution levels at three sites: Kentmere Ave, Ramsgate (suburban), The Square Birchington (roadside hotspot) and Boundary Road, Ramsgate (roadside), as well as extending the number of diffusion tube locations across Thanet to Tonbridge and Malling Borough Council The Annual Progress Report 2014 made the following observations regarding air quality monitoring by Tonbridge and Malling Borough Council (TMBC) in 2013: Confirmed that concentrations within four of the existing AQMA areas, continue to exceed the NO2 air quality objectives: Aylesford AQMA, Borough Green AQMA, Tonbridge AQMA and Wateringbury AQMA. Noted that the Ditton AQMA has not experienced any exceedences of the annual mean objective at locations with relevant exposure since Consideration could be given to revoking this AQMA. Noted that there were no exceedences of the annual mean objective at locations within the M20 and Larkfield AQMAs in 2013 but monitoring should continue to identify and confirm any changes as 2012 had seen levels within 10% of the objective. Diffusion tube monitoring identified a potential exceedence of the 1-hour mean nitrogen dioxide objective at locations within the existing Wateringbury AQMA. The council is focussed upon action planning in this area and continues to pursue measures to tackle air pollution in Wateringbury. During 2014 air quality actions completed by TMBC include: i. Continuing to work in partnership with Maidstone Borough Council (MBC), Kent County Council (KCC) and Arriva to implement retrofitting of up to ten Arriva buses with emission abatement equipment on a route between Kings Hill and Maidstone (following a successful application to Defra for funding through the Air Quality Grant regime). ii. Working with developers to include low emission alternatives within the design statement for proposed developments to endeavour to achieve an air quality neutral or air quality positive impact as a result of their proposed development. iii. Continuing to work with local bus operators to limit unnecessary exhaust fume generation through clamping down on idling engines and encouraging green driver behaviour. iv. Engaging with public health officials to raise air quality awareness amongst professionals including the award of funding for a KMAQP led awareness project. v. Supported the successful installation of two fast electric vehicle charging points at in Kings Hill. vi. Continuing to pursue the installation of two rapid electric vehicle charging points within the borough. vii. Continued to engage with County and Highway s Transport colleagues to facilitate air quality improvements, for example consideration of an eastward facing slip to Junction 5 of the M25. viii. Supported KCC successful bid for grant funding to improve Tonbridge High Street with the aim to improve air quality. For more information please visit ix. Supported the successful bid for LSTF funding bid for Revenue and Capital funding. Capital included Snodland Station redevelopment (which compliments previous work on promoting the Medway Valley line); Revenue included website and public transport app, smart ticketing, business support, green driving and interchange audits. x. Successfully engaged with local primary schools as part of Science Week through the teaching of air quality lessons.

84 8.12 Tunbridge Wells Borough Council Kent and Medway Air Quality Monitoring Network 79 The 2015 Updating and Screening Assessment concluded that NO2 diffusion tube and continuous monitoring should continue in the district to identify future changes in pollutant concentrations in and around the A26 Air Quality Management Area. A publicly accessible Car Club launched in September 2014 in Tunbridge Wells with two vehicles located near the train station and the Town Hall and operated by Co-wheels, a social enterprise. The scheme - kick-started with the support of S106 funding - has been successful beyond expectations: an electric vehicle is being added to the fleet, and the addition of further vehicles will be considered in Anyone can become a member of the car club by registering on Co-Wheels website. Working in partnership with Kent County Council and the Department for Transport, two free-to-use fast charging points for electric vehicles were installed in Tunbridge Wells in Each point can charge up two cars at the same time and is accessible 24/7. Registration with Charge Your Car (CYC) and cables compatible with a 7kW fast charger are required to use the charging points. The charging points are located in marked bays within Great Hall and Crescent Road car park. A second bay at Crescent Road is currently reserved to a Car Club electric vehicle. Further charging points, contribution to the local car club, and incentives towards sustainable transport are being introduced through requirements on new developments.

85 RICARDO-AEA Kent and Medway Air Quality Monitoring Network Appendices Appendix 1: Locations of monitoring sites in 2014 Appendix 2: Site names and closed sites Appendix 3: UK national air quality objectives

86 RICARDO-AEA Kent and Medway Air Quality Monitoring Network Appendix 1 - Locations of monitoring sites operational in 2014 No. Location Pollutants No. Location Pollutants 1 Canterbury (AURN except PM10) NO2, PM10 (TEOM) 14 Maidstone Rural NO2, O3, PM10 (FDMS-TEOM), SO2 2 Canterbury Military Roadside NO2 15 Rochester Stoke (AURN) NO2, O3, PM10 (TEOM), PM2.5 (TEOM), SO2 3 Canterbury Roadside NO2 16 Swale Ospringe Roadside 2 NO2, PM10 (TEOM) 4 Canterbury St Peters Place NO2 17 Swale Newington 3 NO2 5 Chatham Centre Roadside (AURN) NO2, PM10 (FDMS- TEOM), PM2.5 (FDMS-TEOM) 18 Swale Canterbury Road NO2 6 Chatham Luton Background (Closed 20/03/2014) CO, NO2, O3, PM10 (TEOM), SO2 19 Swale St Pauls NO2