2012 Air Quality Updating and Screening Assessment for Isle of Anglesey County Council
In fulfillment of Part IV of the Environment Act 1995 Local Air Quality Management
October 2012
Adain Gwasanaethau Amgylcheddol, Environmental Services Section, Cyngor Sir Ynys Môn, Isle of Anglesey County Council, Swyddfa’r Sir, County Offices, LLANGEFNI, LLANGEFNI, Ynys Môn, Anglesey. LL77 7TW. LL77 7TW.
(01248) 752820 (01248) 752820
Isle of Anglesey C.C.
Local Authority Huw Arfon Thomas Officer
Department Environmental and Technical Services Address County Offices, Llangefni. Telephone (01248) 752823 e-mail [email protected]
Report Reference IACC:LAQM2012 number Date October 2012
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Executive Summary
During 2011/12 the Local Authority continued to undertake diffusion tube monitoring at the kerbside of the A55(T) at Llanfair P.G. Several years’ monitoring data is available for this site and this offers the Local Authority the ability to monitor trends in roadside NO2 concentrations. This is the sole location on the island where the 40 µg/m3 annual average objective is exceeded. Despite the fact that there are no receptors present for the annual mean to apply, the diffusion tube is located near an authorised lay-by with no time restriction on its use, where the 1 hour objective of 200µg/m3 (which is not to be exceeded more than 18 times a year), would apply. Recently, NO2 concentrations have been rising steadily at this location, with the 2010 levels reaching 49.4µg/m3 an 8.7µg/m3 rise on 2005. Continued increases of this magnitude meant that roadside annual mean concentrations of over 60µg/m3 may have been possible with 5 – 10 years. This is the annual mean concentration suggested within the technical Guidance LAQM.TG (09) as being likely to give rise to exceedences of the 1 hour mean objective for NO2. In 2011, the Local Authority witnessed a halting in this rise, with a sharp fall in annual average NO2 concentrations on the previous year. The measured level of 44.6µg/m3 in 2011 was similar to concentrations last seen at this location in 2008.
The Local Authority reported in its 2011 Progress Report that it had commenced a 12 month NO2 diffusion tube monitoring study at Newry Beach, Holyhead. This study was concluded in 2011 and the annual average for the entire 12 month study period was 11.47µg/m3, significantly less than the air quality objective of 40µg/m3.
It is recognised that the potential construction of a new nuclear power station at Wylfa, near Cemaes, could create increased traffic flows upon the A5025 from Cemaes to Valley and road improvements are currently being considered. Although a decision to build the nuclear power station has yet to be made, during 2011 the Local Authority began a baseline NO2 diffusion tube study at four locations along the road at Cemaes, Tregele, Llanfaethlu and Llanfachraeth. Although it will not be possible to report the full bias corrected results until the next progress report in 2013 (because some of the study was undertaken in 2012), 9 months’ data was collected in for 2011
Anglesey USA 2012 2 Isle of Anglesey C.C. and the averages for this period were in the order of 6 – 7µg/m3, barely above the background levels quoted in the 2011 background maps. Should a decision be made to undertake improvements to the A5025 between Cemaes and Valley a more detailed assessment would be required.
In order to gain measured background levels of NO2 for Llangefni, a 12 month diffusion tube study was begun near to a car showroom, (one of the relevant receptors), at Llangefni industrial estate. Insufficient data was gathered during 2011 for an annual average level to be included in this report but this will be included in the 2013 progress report.
For a number of years the Local Authority has reported PM10 monitoring undertaken at two Quarries on the island, Gwyndy Quarry at Llynfaes and Rhuddlan Bach Quarry at Brynteg. The Turnkey Osiris monitors are owned by the individual quarries and managed by the Local Authority, with the data downloaded several times a data onto the Welsh Air Quality Database. In 2011 the Local Authority commissioned two additional PM10 monitoring sites, using its own Turnkey Osiris monitors. The first location was Llangefni Library. The 2011 Progress Report highlighted a proposal for the construction of a Biomass Combined Heat and Power plant at the Bryn Cefni Industrial Estate, Llangefni. Apart from data from the background maps, the Local Authority had no information on existing PM10 levels in or around Llangefni. Consequently, a monitor was installed on the roof of Llangefni library on the 22 June 2011. The second new PM10 monitoring location was at a composting facility near the civic amenity site at Penhesgyn, Menai Bridge. In a joint exercise with the Waste Management Section, the Environmental Health Section decided to conduct a study to examine the levels of PM10 at the site. During 2011 the results from all 4 automatic PM10 monitors were below the Welsh Government’s 24 hour mean objective of 50µg/m3 (not exceeded on more than 35 days per year) and the annual mean of 40µg/m3.
With up to 4 monitors in operation at any one time, the local authority is able to compare exceedences to determine whether the source is local or transboundary in nature. The monitor at Brynteg showed the highest number of exceedences with 5, followed by Llynfaes with 3, Llangefni with 1 and Penhesgyn with none. The single
Anglesey USA 2012 3 Isle of Anglesey C.C. exceedence at Llangefni occurred on the same day as an exceedence at LLynfaes and Brynteg, on the 10th October 2011. This date also provided the single highest 24hr hour level for Penhesgyn during 2011. Local meteorological reports suggest that a deposit of Sahara dust fell over Anglesey on the 9th and 10th October 2011, causing elevated PM10 levels. Although the Llangefni monitor registered the highest 24hour concentration on the 10th with a level of 62.8µg/m3, the difference between it and the other two sites with exceedences was virtually insignificant (Brynteg [61.68µg/m3] and Llynfaes [61.5µg/m3]). Local reports suggest that Sahara dust deposition may have also occurred on the 26th/ 29th of March and 26th December 2011. Each of these days accounted for an exceedence at one of the PM10 monitors.
From the 10th September 2010 to 31st August 2011 the Local Authority undertook deposit gauge monitoring at 4 locations near the Henwaith Settlement Ponds, Parys Mountain. The first quarter showed slightly elevated readings at all four locations; possibly because this coincided with the remediation work being undertaken at the ponds. From December 2010 onwards the deposition results for Cerrig Bleiddiau [28.5mg/m2/day], Pen y Corn [21.85mg/m2/day] and Tai Fry [25.96mg/m2/day] remain similar. The Local Authority is able to report that the annual deposit rates for the study period at these three properties are well within the typical deposition rates normally quoted for rural areas. The deposition results for Henwaith [67.13mg/m2/day] show a significant reduction in deposited dust at this location since the completion of the remedial work. Although the deposit gauges at Cerrig Bleiddiau, Pen y Corn and Tai Fry were removed at the end of August 2011, the deposit gauge at Henwaith would remain for a further 12 months.
In September 2011 the Environmental Health Section received a planning consultation request for the construction of an energy centre for a 600kW biomass boiler at Tre Ysgawen Hall, Capel Coch. A screening assessment is included in this report, but the result suggested that neither the PM10 24hr and NO2 1hr objectives were likely to be exceeded. In order to verify the outcome of this assessment the Local Authority required a 12 month NO2 diffusion tube survey to be undertaken. This monitoring commenced at the end of April 2012 and the results will be included in the 2013 progress report. Early indications are that monthly average NO2 levels are very low.
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This report includes a brief synopsis of assessments the Local Authority has previously undertaken with regard to a number of specified areas. These include congested or busy streets, poultry farms and railway stations. The Local Authority had not previously considered airports because there were none within its area which met the screening assessment criteria. Despite this, there is a busy RAF airfield at Valley and the Local Authority gives further consideration to NO2 levels from the airfield under the heading “airports” and reports that the highest annual mean NO2 level was well below the 40µg/m3 air quality objective.
Previous reviews and assessments are available on the Council’s web site:- http://www.anglesey.gov.uk/planning-and-waste/environmental-health/pollution/air- quality/
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Table of contents
1 Introduction ...... 10 1.1 Description of Local Authority Area ...... 10 1.2 Purpose of Report ...... 11 1.3 Air Quality Objectives ...... 13 1.4 Summary of Previous Review and Assessments ...... 14 2 New Monitoring Data ...... 15 2.1 Summary of Monitoring Undertaken ...... 15 2.1.2 Non-Automatic Monitoring Sites ...... 22 2.2 Comparison of Monitoring Results with AQ Objectives ...... 24 2.2.1 Nitrogen Dioxide ...... 24
2.2.2 PM10 ...... 28 2.2.3 Sulphur Dioxide...... 31 2.2.4 Benzene ...... 32 2.2.5 Other pollutants monitored ...... 32 3 Road Traffic Sources ...... 36 3.1 Narrow Congested Streets with Residential Properties Close to the Kerb ...... 36 3.2 Busy Streets Where People May Spend 1-hour or More Close to Traffic ...... 36 3.3 Roads with a High Flow of Buses and/or HGVs...... 38 3.4 Junctions ...... 38 3.5 New Roads Constructed or Proposed Since the Last Round of Review and Assessment 38 3.6 Roads with Significantly Changed Traffic Flows ...... 39 3.7 Bus and Coach Stations ...... 40 4 Other Transport Sources ...... 41 4.1 Airports ...... 41 4.2 Railways (Diesel and Steam Trains) ...... 42 4.2.1 Stationary Trains ...... 42 4.2.2 Moving Trains ...... 43 4.3 Ports (Shipping) ...... 43 5 Industrial Sources ...... 44 5.1 Industrial Installations ...... 44 5.1.1 New or Proposed Installations for which an Air Quality Assessment has been Carried Out 44 5.1.2 Existing Installations where Emissions have Increased Substantially or New Relevant Exposure has been Introduced ...... 50 5.1.3 New or Significantly Changed Installations with No Previous Air Quality Assessment ... 50 5.2 Major Fuel (Petrol) Storage Depots ...... 53 5.3 Petrol Stations...... 53
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5.4 Poultry Farms...... 53 6 Commercial and Domestic Sources ...... 55 6.1 Biomass Combustion – Individual Installations ...... 55 6.2 Biomass Combustion – Combined Impacts ...... 57 6.3 Domestic Solid-Fuel Burning ...... 57 7 Fugitive or Uncontrolled Sources ...... 58 8 Conclusions and Proposed Actions ...... 59 8.1 Conclusions from New Monitoring Data ...... 59 8.2 Conclusions from Assessment of Sources ...... 60 8.3 Proposed Actions ...... 61 9 References ...... 62
List of Tables Table 1.2 Summary of previous Air Quality Reports published by the Local Authority. ………………………………………………………………………….13
Table 2.1 Details of Automatic Monitoring Sites ………………………………………….21
Table 2.2 Details of Non-Automatic Monitoring Sites ……………………………………23
Table 2.3 Nitrogen Dioxide Fall-off with distance at A55(T) Llanfair P.G. ……………...24
Table 2.4 Results of Nitrogen Dioxide Diffusion Tubes in 2011………………………...26
Table 2.5 Results of Nitrogen Dioxide Diffusion Tubes (2007 to 2011)………………...27
Table 2.6 Results of Automatic Monitoring of PM10: Comparison with
Annual Mean Objective …………………………………………………………29
Table 2.7 Results of Automatic Monitoring for PM10: Comparison with
24-hour mean Objective…………………………………………………………29
Table 2.8 Results of dry foam Frisbee deposit gauges Henwaith settlement Ponds, Amlwch. …………………………………………………….34
Table 5.1: Principal emissions from proposed CHP Biomass Plant…………………….45
Table 6.1: Summary of results for biomass boiler at Tre Ysgawen Hall, Capel Coch. ………………………………………………………………..56
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List of Figures
Figure 2.1 Map showing the Location of the PM10 monitoring device at Creigiau in relation to Gwyndy Quarry, Llynfaes. ……………………………...15
Figure 2.2 Map showing the Location of the PM10 monitoring point at Chwarelau, Brynteg. ……………………………………………………..……….16
Figure 2.3 Map showing the Location of the PM10 monitoring point at Llangefni Library………………………………………………………………….. 17
Figure 2.4 Photograph of Turnkey-Osiris PM10 monitor at In-Vessel Composting Plant, Penhesgyn. …………………………………………………18
Figure 2.5 Map showing the Location of the PM10 monitoring point at Penhesgyn. ………………………………………………………………………. 19
Figure 2.6 Trends in Annual Mean Nitrogen Dioxide Concentrations measured at Diffusion Tube Monitoring Sites [µg/m3] ………………………...27
Figure 2.7 Sahara Dust event 10th October 2011. …………………………………………30
Figure 2.8 Sahara Dust event 26th December 2011. ………………………………………30
Figure 2.9: Locations of Frisbee Dust Deposit gauges Henwaith Settlement Ponds, Parys Mountain. ………………………………………………………….33
Figure 2.10 Dry foam Frisbee dust deposit gauge results Henwaith settlement ponds………………………………………………………………………………35
Figure 5.1 Photograph of compost storage area at the Composting Plant, Penhesgyn. ……………………………………………………………………….51
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Appendices Appendix A: QA:QC Data Diffusion Tube Bias Adjustment Factors Discussion of Choice of Factor to Use PM Monitoring Adjustment Short-term to Long-term Data adjustment QA/QC of automatic monitoring QA/QC of diffusion tube monitoring
Appendix B: Diffusion Tube Data Set
Appendix C: Maps of diffusion tube locations.
A55(T) Llanfair P.G. London Road, Holyhead. RAF Valley. Newry Beach, Holyhead. Llanfachraeth. Llanfaethlu. Tregele/Wylfa. Cemaes. Llangefni Industrial Estate
Appendix D: PM10 Exceedences.
Appendix E: List of Poultry Rearing Units.
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1 Introduction 1.1 Description of Local Authority Area
Anglesey is an island situated off North West Wales. It is linked to the mainland by two historic bridges, Telford’s Menai Suspension Bridge (built as part of the A5 London to Holyhead route) and Stephenson’s Britannia Bridge. The latter was originally designed to carry the railway across the Menai Straits but now also houses an upper deck forming part of the A55(T).
With an area covering some 720km2 and a population of 67,864 Anglesey is predominantly rural with a number of scattered towns and villages. The principal towns are Holyhead, Llangefni, Amlwch, Menai Bridge and Beaumaris. In recent years the Island has seen the closure of a number of industrial processes and in 2009, smelting activities cessed at Anglesey Aluminium Metals Ltd.
Suffering from significant job losses, deprivation and outward migration there is a pressing need locally to consider a different approach to economic, social and environmental development. Faced with the challenges of climate change and energy security issues, the Local Authority and its partners recognise the island’s potential to create a world-renowned centre of excellence for the production, demonstration and servicing of low carbon energy. This has developed into a vision of Anglesey as the “Energy Island” and a recent announcement by the Welsh Government established it as an Enterprise Zone focusing on Energy.
The Island is home to Wylfa nuclear power station which is likely to undergo decommissioning from 2014 onwards. The existing Wylfa site is also one of 8 sites in the UK deemed strategically suitable for nuclear development. Despite a decision by the parent Companies of Horizon Nuclear Power not to proceed to develop new nuclear power projects in the UK, the site remains of strategic importance and the Company is actively seeking other potential investors.
The Island has three existing wind farms and there are plans for further onshore and offshore wind projects, together with a tidal stream array between the mainland and a group of islands called the Skerries.
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Other renewable projects include the development of a 299MW Biomass Renewable Energy Plant on land within the boundary of the existing Anglesey Aluminium smelter at Holyhead and a Biogas Plant at Mona Industrial Estate. Both of which have received planning consent. There are also proposals, for a Biomass Plant and wood pelletizing plant at the site of the former Peboc site at Llangefni Industrial estate. Although planning permission has been refused for the site, this is now the subject of Appeal. On a smaller scale, over the last 12 months there has been a surge in the number of applications for small scale wind turbine. Smaller commercial biomass boilers remain relatively few in number and low density.
The island has a number of Poultry Farms, Quarries and the former historic copper mine at Parys Mountain, each with the potential for fugitive dust emissions. All of these have been the subject of previous detailed assessments. The Local Authority continues to manage two Turnkey Osiris PM10 monitors owned by two of the quarries, with data uploaded daily into the Welsh Air Quality Website.
Holyhead remains the principal shipping port serving Dublin and being within relatively close proximity to attractions such as Snowdonia National Park it has become the premier Welsh cruise liner destination. Located close to the port is the terminus of the main un-electrified railway line linking Holyhead with Chester.
The A55(T) duel carriageway begins at Holyhead and runs in south easterly direction across the island, skirting several towns and villages which lie on the original route of Telford’s A5. The A55(T) has become the most heavily used road on the Island and has significantly reduced traffic congestion in many of the villages along the A5.
1.2 Purpose of Report
This report fulfils the requirements of the Local Air Quality Management process as set out in Part IV of the Environment Act (1995), the Air Quality Strategy for England, Scotland, Wales and Northern Ireland 2007 and the relevant Policy and Technical Guidance documents. The LAQM process places an obligation on all local authorities to regularly review and assess air quality in their areas, and to determine whether or not the air quality objectives are likely to be achieved. Where exceedences are considered likely, the local authority must then declare an Air Quality Management
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Area (AQMA) and prepare an Air Quality Action Plan (AQAP) setting out the measures it intends to put in place in pursuit of the objectives.
The objective of this Updating and Screening Assessment is to identify any matters that have changed which may lead to risk of an air quality objective being exceeded. A checklist approach and screening tools are used to identify significant new sources or changes and whether there is a need for a Detailed Assessment. The USA report should provide an update of any outstanding information requested previously in Review and Assessment reports.
LAQM USA 2012 12 Isle of Anglesey C.C. 1.3 Air Quality Objectives
The air quality objectives applicable to LAQM in Wales are set out in the Air Quality (Wales) Regulations 2000, No. 1940 (Wales 138), Air Quality (Amendment) (Wales) Regulations 2002, No 3182 (Wales 298), and are shown in Table 1.1. This table shows the objectives in units of microgrammes per cubic metre g/m3 (milligrammes per cubic metre, mg/m3 for carbon monoxide) with the number of exceedences in each year that are permitted (where applicable).
Table 1.1 Air Quality Objectives included in Regulations for the purpose of LAQM in Wales Air Quality Objective Date to be Pollutant Concentration Measured as achieved by Running annual 16.25 µg/m3 31.12.2003 mean Benzene Running annual 5.00 µg/m3 31.12.2010 mean Running annual 1,3-Butadiene 2.25 µg/m3 31.12.2003 mean Running 8-hour Carbon monoxide 10.0 mg/m3 31.12.2003 mean 0.5 µg/m3 Annual mean 31.12.2004 Lead 0.25 µg/m3 Annual mean 31.12.2008 200 µg/m3 not to be exceeded more than 1-hour mean 31.12.2005 Nitrogen dioxide 18 times a year 40 µg/m3 Annual mean 31.12.2005 50 µg/m3, not to be exceeded more than 24-hour mean 31.12.2004 Particles (PM10) (gravimetric) 35 times a year 40 µg/m3 Annual mean 31.12.2004 350 µg/m3, not to be exceeded more than 1-hour mean 31.12.2004 24 times a year 125 µg/m3, not to be Sulphur dioxide exceeded more than 24-hour mean 31.12.2004 3 times a year 266 µg/m3, not to be exceeded more than 15-minute mean 31.12.2005 35 times a year
LAQM USA 2012 13 Isle of Anglesey C.C. 1.4 Summary of Previous Review and Assessments
This Progress report is part of a continuing review process which began with the publication of the first Air Quality Updating and Screening Assessment (USA) in 2003. A summary of previous reports is included in Table 1.2 below and copies of all the reports are available on Council’s web site1.
Table 1.2 Summary of previous Air Quality Reports published by the Local Authority.
Year Updating Progress Detailed Assessment AQMA and Report Recommended Declared screening assessment 2003 No No 2004 No No 2005 No No 2006 No No 2007 Yes SO2 – 15 minute No mean objective for Penrhos Coastal Park 2008 No No 2009 Yes SO2 – 15 minute No mean objective for Holyhead Railway Station 2010 No No 2011 No No
The pollutants that have been highlighted in the past as being of principal significance have been Nitrogen Dioxide from various roads, Sulphur Dioxide from domestic coal burning, smelting and Railway Locomotives, together with PM10 from quarries and poultry farms. Although the Local Authority has been required to undertake more detailed assessments for all these processes, these have not revealed any exceedences of the objective concentrations and to date it has not been necessary to declare an Air Quality Management Area.
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2 New Monitoring Data 2.1 Summary of Monitoring Undertaken
2.1.1 Llynfaes (PM10)
The Local Authority continues to manage and operate a Turnkey Osiris PM10 monitor owned by Hogan Bros Ltd, Gwyndy Quarry, Llandrygan. The instrument is located at the property known as Creigiau and the data reported is courtesy of Hogan Bros Ltd. The following map shows the locations of the monitoring location in relation to the quarry.
Figure 2.1 Map showing the Location of the PM10 monitoring device at
Creigiau in relation to Gwyndy Quarry, Llynfaes.
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2.1.2 Brynteg (PM10).
The Local Authority continues to manage and operate a Turnkey Osiris PM10 monitor owned Clive Hurt Plant Hire Ltd, Rhuddlan Bach Quarry, Brynteg. The instrument is located at the property known as at “Chwarelau” and the data reported is courtesy of Clive Hurt Plant Hire Ltd. The following map shows the locations of the monitoring location in relation to the quarry.
Figure 2.2 Map showing the Location of the PM10 monitoring point at Chwarelau, Brynteg.
2.1.3 Llangefni (PM10).
The 2011 Progress Report highlighted a proposal for the construction of a Biomass Combined Heat and Power plant at the Bryn Cefni Industrial Estate, Llangefni. Technical Guidance suggested that the primary pollutants of concern for larger scale commercial biomass plants are PM10 and NO2. Apart from data from the background maps, the Local Authority had no information on existing PM10 levels in or around
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Llangefni. Consequently, a Turnkey Osiris instrument was installed on the roof of Llangefni library on the 22nd June 2011. This location was chosen because it was secure, yet free from obstruction in free moving air. Care was taken to ensure that there were no local sources such as flues on the roof, which could interfere with the results. The following map shows the location of the monitor.
Figure 2.3 Map showing the Location of the PM10 monitoring point at Llangefni Library.
2.1.4 Penhesgyn composting plant (PM10).
Located near to a civic amenity site at Penhesgyn is an in-vessel composting plant which processes organic material from the Council’s green and kitchen waste collections. Handling composted material can give rise to the release of airborne
LAQM USA 2012 17 Isle of Anglesey C.C. particulate matter, derived from organic based material (often cellulose-based) and micro-organisms such as fungi, molds, spores and bacteria2. These suspended particles can range in size from 0.5 to 100µm, which means that some of the particles will fall within the 10µm limit of PM10. In a joint exercise with the Waste Management Section, the Environmental Health Section decided to conduct a study to examine the levels of PM10 at the site and monitoring commenced on the 7th October 2011, initially for a period of 12 months.
Figure 2.4 Photograph of Turnkey-Osiris PM10 monitor at In-Vessel Composting Plant, Penhesgyn.
For security and in order to gain access to an electricity supply, the PM10 monitor was located on the roof of the main composting building adjacent to where the compost is removed from the tunnels. It was situated in a downwind direction between the closest residential property and the main compost handling area. The on-site concentrations of dust are likely to be considerably higher than at the closest relevant exposure, determined as being the closest residential property,
LAQM USA 2012 18 Isle of Anglesey C.C. approximately 100m to the South East. The following map shows the location of the monitor.
Figure 2.5 Map showing the Location of the PM10 monitoring point at Penhesgyn.
As part of its normal QA/QC procedure, the Local Authority undertakes routine filter changes and air flow checks (600ml/min) on the Osiris instruments normally on a quarterly basis. This is in addition to an annual service and calibration undertaken by
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Turnkey instruments under the terms of a service contract. The data is downloaded electronically from each instrument approximately 2 – 3 times a week using a GSM modem. This enables the performance of the instrument to be monitored and for problems to be rectified quickly, with minimum loss of data. The data is stored as 15 minute averages and is analysed using a dedicated software system (AirQ32). A visual data ratification process is employed, to safeguard against erroneous peaks etc., before any results are reported.
In previously reported studies, the Local Authority has demonstrated that an adjustment factor of x1.3 would lead to a significant overestimation of the impact of coarse dust from quarry processes. The Environment Agency’s Guidance on monitoring of particulate matter in ambient air around waste facilities also suggests that composting facilities make little contribution to “PM2.5 as their emissions are likely to consist mainly of coarse particles”2. As such, the Local Authority does not believe that an adjustment of x1.3 would be appropriate for the data gathered near the composting facility. Although the monitor at Llangefni Library was merely measuring background levels, comparisons of the episodes of Saharan dust suggests that a x1.3 would also produce a significant overestimation of concentrations at this location.
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Table 2.1 Details of Automatic Monitoring Sites Relevant Exposure? Distance to (Y/N with kerb of distance nearest (m) to road Does this location X OS Y OS Grid Pollutants Monitoring relevant (N/A if not represent worst- Site Name Site Type GridRef Ref Monitored In AQMA? Technique exposure) applicable) case exposure? Llynfaes Turnkey Rural 239692 379774 PM No Y (1m) 10m Y (Creigiau) 10 Osiris Brynteg Turnkey Rural 381325 248566 PM10 No Y (1m) 5m Y (Chwarelau) Osiris Llangefni Turnkey Town 246022 379774 PM10 No Y (10m) 10m Y Library Osiris IVC Site Composting Turnkey 253280 374160 PM10 No Y (100) 20m Y Penhesgyn Plant. Osiris
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2.1.5 Non-Automatic Monitoring Sites
The Local Authority has continued to monitor Nitrogen Dioxide (NO2) using diffusion tubes at various sites across the Island (as outlined in table 2.2 below). The tubes were supplied by Environmental Scientifics Group [ESG], Didcot, Oxfordshire, using a preparation of 50% Triethanolamine (TEA) in water.
Diffusion tubes may systematically under or over read NO2 concentrations when compared with Chemiluminescence analysers (which are the preferred reference method for measuring this pollutant); this is referred to as “bias”. This bias may be corrected using a “bias adjustment factor” calculated from spreadsheets available from the Review and Assessment web site. The latest spreadsheet was used for the purpose of this Updating and Screening Assessment (v07/12)3.
ESG’s precision results for collocated NO2 Diffusion Tubes were rated as “Good Precision” in 2011. Precision reflects a laboratory’s performance/consistency in preparing and analysing those tubes used in a collation study to determine diffusion tube bias, as well as the subsequent handling of the tubes in the field4. The laboratory also participates in the independent Workplace Analysis Scheme for Proficiency (WASP) and 100% of results submitted in 2011 were determined to be satisfactory5. . Maps showing the locations of all the Non-Automatic Monitoring Sites are included at Appendix C.
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Table 2.2 Details of Non-Automatic Monitoring Sites Is monitoring Relevant collocated Exposure? Distance to Does this with a (Y/N with kerb of location Continuous distance (m) nearest road represent X OS Grid Y OS Grid Pollutants Analyser to relevant (N/A if not worst-case Site Name Site Type Ref Ref Monitored In AQMA? (Y/N) exposure) applicable) exposure? Llanfair P.G. By-pass Roadside 252700 372100 NO2 No No N (Kerbside) 1m Y
London Road, Roadside 225664 381550 No No Y 1m 2m Y NO2 Holyhead Newry Beach, Roadside 224570 383169 No No Y 1m 3m Y NO2 Holyhead RAF Valley Roadside 230945 376297 NO No No Y 1m 1m Y 2 A5025 Roadside 231506 382412 NO No No Y 1m 1m Y Llanfachraeth 2 A5025 Roadside 213447 386901 NO No No Y 1m 1m Y Llanfaethlu 2 A5025 Roadside 235774 392938 NO No No Y 1m 1m Y Tregele 2 A50205 Roadside 236932 393102 NO No No Y 1m 1m Y Cemaes 2
Bryn Cefni Industrial Est. 246410 375080 NO2 No No Y 1m 1m Y
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2.2 Comparison of Monitoring Results with AQ Objectives
2.2.1 Nitrogen Dioxide
Diffusion Tube Monitoring Data
The NO2 diffusion tube results for the kerbside of the A55(T) at Llanfair P.G. are the only ones which are greater than the Welsh Assembly Government’s annual objective of 40μg/m3 for this pollutant. Despite this, there are no relevant exposures for that averaging period at the kerbside. NO2 levels reduce very rapidly with distance from kerbside and a specific tool available on the LAQM website can be used to demonstrate this effect6.
Based upon an estimated background concentration of 6.98ug/m3 from (grid square 252500, 372500) the background maps for 20117, a concentration of 44.6ug/m3 (measured 1m from the kerb) would result in the following predicted concentrations with distance from kerbside:-
Table 2.3 Nitrogen Dioxide Fall-off with distance at A55(T) Llanfair P.G.
Distance from 5 10 15 20 kerbside (m) Predicted Annual Mean 32.4 27.1 24.1 21.9 Concentration (µg/m3)
Despite roadside concentrations being above the annual objective, the concentrations soon fall below it with minimal distances from the kerb. However, the NO2 diffusion tube location at Llanfair P.G. is situated near to an authorised lay-by with no time restriction on its use, a location where the 1 hour objective of 200 µg/m3 (which is not to be exceeded more than 18 times a year), would apply. Although 1 hour measurements have not been undertaken, the technical Guidance LAQM.TG(09)8 states that a Local Authority may assume that the 1 hour mean objective for NO2 is unlikely to be exceeded where the annual mean concentration remains below 60 µg/m3.
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Figure 2.6 shows the annual trends in Nitrogen Dioxide Concentrations at this site from 2001 to 2011. Since 2005 annual mean levels had been rising steadily in line with a trend observed nationally. Nevertheless, the 2011 annual mean shows a marked drop on levels measured in 2010 and a return to levels last seen in 2008.
In addition to the A55(T) at Llanfair P.G. the Local Authority has also undertaken diffusion monitoring at a roundabout at London Road, Holyhead, RAF Valley, Newry Beach, Holyhead, and Llangefni Industrial Estate, together with four sites along the A5025. The results of these studies are documented in table 2.4 and are all within the Air Quality Objective of 40µg/m3.
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Table 2.4 Results of Nitrogen Dioxide Diffusion Tubes in 2011 Data with Confirm if Annual mean less than 9 data has concentration Triplicate Data months has been (Bias Adjustment or Capture been distance factor = 0.83) Site Within Collocated 2011 annualised corrected ID Location Site Type AQMA? Tube (%) (Y/N) (Y/N) 2011 ( g/m3) A55(T) N 100% 1 N N/A N 44.6 Llanfair P.G. Roadside 11.2 83.3% 2 Newry Beach, N N N/A N [11.47]c [100%]c Holyhead Roadside 10.24 3 N N 25% N N RAF Valley Nr Airfield [7.91]c A5025 6.87a,b 4 N N 58.3% N N Llanfachraeth. Roadside A5025 75% 6.21a,b 5 N N N/A N Llanfaethlu Roadside A5025 75% 6.16a,b 6 N N N/A N Tregele Roadside A5025 75% 6.87a,b 7 N N N/A N Cemaes Roadside Llangefni Urban 8 Industrial background N N 16% N N/A b. Estate a: Part of 12 month study running into 2012 b: Annual mean will be reported in 2013. c: Based on 12 month study period including months in 2010.
.
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Isle of Anglesey C.C. Table 2.5 Results of Nitrogen Dioxide Diffusion Tubes (2007 to 2011) Annual mean concentration (adjusted for bias) g/m3 Within Site 2007 2008 2009 2010 2011 Site ID AQMA Type (Bias (Bias (Bias (Bias (Bias ? Adjustment Adjustment Adjustment Adjustment Adjustment Factor = 0.88) Factor = 0.83) Factor = 0.81) Factor = 0.84) Factor = 0.83) A55(T) Roadside N 43.9 44.5 45.1 49.4 44.6 Llanfair P.G.
Figure 2.6 Trends in Annual Mean Nitrogen Dioxide Concentrations measured at Diffusion Tube Monitoring Sites [µg/m3]
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Isle of Anglesey C.C.
2.2.2 PM10
The results from all automatic PM10 monitors have consistently been below the Welsh Government’s 24 hour mean objective of 50µg/m3 (not exceeded on more than 35 days per year) and the annual mean of 40µg/m3.
On occasions during 2011 the Local Authority had up to 4 Turnkey Osiris monitors in operation. This number of monitors allows the local authority to compare exceedences to determine whether the source is local or transboundary in nature. The monitor at Brynteg showed the highest number of exceedences with 5, followed by Llynfaes with 3, Llangefni with 1 and Penhesgyn with none. Interestingly, the single exceedence at Llangefni occurred on the same day as exceedences at LLynfaes and Brynteg, namely the 10th October 2011. This date also provided the single highest 24hr hour level for Penhesgyn during 2011 [43.3µg/m3]. Local meteorological reports suggest that a deposit of Sahara dust fell on Anglesey on the 9th and 10th October 2011, causing elevated PM10 levels. Although the Llangefni monitor registered the highest 24hour concentration on the 10th, with a level of 62.8µg/m3, the difference between it and the other two sites with exceedences was virtually insignificant (Brynteg [61.68µg/m3] and Llynfaes [61.5µg/m3]). Figure 2.7 illustrates the PM10 levels at all four locations on the 10th October.
Local reports suggest that Sahara dust deposition may have also occurred on the 26th/ 29th of March and 26th December 2011. Figure 2.8 shows a clear relationship between all four monitors on 25th – 26th December 2011.
In previously reported studies, the Local Authority has demonstrated that an adjustment factor of x1.3 would lead to a significant overestimation of the impact of coarse dust from quarry processes. The particles of interest from the composting plant at Penhesgyn are also likely to be coarse in nature. Although the monitor at Llangefni Library was merely measuring background levels, close similarities between this site and other sites on the island during the documented Sahara dust episodes suggests that an x1.3 correction would produce a significant overestimation of concentrations at this location.
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Table 2.6 Results of Automatic Monitoring of PM10: Comparison with Annual Mean Objective Valid Data Valid Confirm Annual Mean Concentration g/m3 Capture for Data Gravimetric Within monitoring Capture Equivalent Site ID Site Type AQMA? Period %a 2011 %b (Y or NA) 2007*c 2008* c 2009* c 2010* c 2011 c Llynfaes Nr Quarry N 65 65 Y 20 18.5 17.9 19.8 Brynteg Nr Quarry N 86.3 86.3 Y NA 18.7 17.9 13.2 18.2 Urban Llangefni N 100 52.9 Y NA NA NA NA 16.8 Background Nr Penhesgyn Composting N 96.4 22 Y NA NA NA NA 16.2 Site.
Table 2.7 Results of Automatic Monitoring for PM10: Comparison with 24-hour mean Objective Valid Data Number of Exceedences of 24-Hour Mean (50 g/m3) Capture Valid for Data Confirm Within monitoring Capture Gravimetric Site ID Site Type AQMA? Period %a 2011 %b Equivalent 2007* 2008* 2009* 2010* 2011 Llynfaes Nr Quarry N 65 65 7 5(33µg/m3) 7(28.9µg/m3) 3(33.6µg/m3) Brynteg Nr Quarry N 86.3 86.3 Y NA 4 4 0(20.1µg/m3) 5(30.2µg/m3) Urban Llangefni N 100 52.9 Y NA NA NA NA 1(28.1µg/m3) background Nr Penhesgyn Composting N 96.4 22 Y NA NA NA NA 0(26.2µg/m3) Site.
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Figure 2.7 Sahara Dust event 10th October 2011.
Figure 2.8 Sahara Dust event 26th December 2011.
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2.2.3 Sulphur Dioxide
No sulphur dioxide monitoring has been undertaken by the Local Authority since it completed a 12 month study at Holyhead train station in 2009/10. The details of this study were reported in the 2010 Progress Report which is available at:- http://www.anglesey.gov.uk/planning-and-waste/environmental-health/pollution/air- quality/
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2.2.4 Benzene
No sulphur dioxide monitoring has been undertaken by the Local Authority
2.2.5 Other pollutants monitored
On the 21st August 2009, following a period of intensive investigation, the Local Authority Determined the Henwaith Settlement Ponds at Parys Mountain as Contaminated Land. The shallow ponds contained an orange clay-like material called “Ochre”, which contained elevated levels of various heavy metals including Arsenic and Lead. During periods of dry weather, the ponds would dry out and the ochre would become readily wind entrained, affecting nearby properties.
In 2010 the Local Authority secured grant funding from the Welsh Assembly Government and undertook remedial work at the site from August to November 2010. The 2009 Updating and Screening Assessment discussed the PM10 monitoring undertaken at Henwaith during 2008. This was undertaken using a Turnkey Osiris instrument with an 81.7% capture rate for the year. The annual mean was found to be 16.3µg/m3 compared to a 40µg/m3 objective, with only one exceedence of the daily mean; lower than either Brynteg or Llynfaes. Despite this, a dust deposit gauge at the site indicated a dust problem which was a factor of 10 higher than the much disputed annual deposition rate of 200mg/m2/day; which is said to represent the threshold for serious nuisance9. High levels of visible dust which was not registering on the PM10 monitor seemed to suggest a particle size greater than 10μm. As a consequence, the Dry Foam Frisbee Gauge method was chosen for monitoring the impact of wind blow dust from the settlement ponds, prior, during and after remedial work. The Protocol for using the dry Frisbee (with foam insert) was based upon that produced by the Stockholm Environment Institute at the University of York10.
The first deposit gauge was located at Henwaith in 2008 and a further three locations were added soon after commencement of the remediation work. The four locations, which are identified on Figure 2.9, were chosen because they represented all those properties likely to be affected by dust from the site during the remediation work. The 2010 background maps7 for PM10 estimate the background concentration for this area (Grid Square 245500, 390500) as being 9.99μg/m3 and based upon the method
LAQM USA 2012 32 Isle of Anglesey C.C. outlined in Box 5.10 of the Technical Guidance, only properties nearer than 200m would need to be considered. The result for each site is presented in Table 2.8.
Figure 2.9: Locations of Frisbee Dust Deposit gauges Henwaith Settlement Ponds, Parys Mountain.
Figure 2.10 shows a comparison for the four sites for the study period 10th September 2010 to 31st August 2011. The first results quarter show slightly elevated readings at all four locations, possibly due to the remediation work. From December 2010 onwards the deposition results for Cerrig Bleiddiau [28.5mg/m2/day], Pen y Corn [21.85mg/m2/day] and Tai Fry [25.96mg/m2/day] remain similar. Indeed, the annual deposit rates for the study period (noted in brackets) are well within the typical deposition rates normally quoted for rural areas9. The deposition results for Henwaith [67.13mg/m2/day] show a positive reduction in deposited dust at this location since the completion of the remedial work. Although the deposit gauges at Cerrig Bleiddiau, Pen y Corn and Tai Fry were removed at the end of August 2011, the deposit gauge at Henwaith would remain for a further 12 months.
The Isle of Anglesey County Council has examined the results from monitoring in the district. Concentrations are all below the objectives, therefore there is no need to proceed to a Detailed Assessment.
LAQM USA 2012 33 Isle of Anglesey C.C. Table 2.8 Results of dry foam Frisbee deposit gauges Henwaith settlement Ponds, Amlwch.
Valid Data Annual Deposit Rate Within Capture for Valid Data (mg/m2/day) AQMA period of Capture 2011 Site ID ? monitoring % % 2008 2009 2010 2011 Henwaith N 100 100 2234a 459 96 66.4 Pen y Corn N 76.5 51 42.4 11.7 Tai Fry N 100 66.5 24.5 26.3 Cerig Bleiddiau N 100 66.5 35.1 26.3
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Deposit Gauge Monitoring Henwaith Settlement Ponds [mg/m2/day] 300
250
200
150 Henwaith Pen y Corn 100 Tai Fry Cerrig Bleiddiau 50
0
10/10/10 8/1/11 10/9/10 9/11/10 9/12/10 7/2/11 9/3/11 8/4/11 8/5/11 7/6/11 7/7/11
Figure 2.10 Dry foam Frisbee dust deposit gauge results Henwaith settlement ponds.
LAQM USA 2012 35 Isle of Anglesey C.C. 3 Road Traffic Sources 3.1 Narrow Congested Streets with Residential Properties Close to the Kerb
Only NO2 needs to be considered for this particular assessment.
It is suggested in the Guidance that a congested street would have daily traffic flows (AADT) of around 5,000 vehicles / day or more. The street would also have slow moving traffic that is frequently stopping and starting throughout much of the day (not just during rush hours) due to pedestrian crossings, parked vehicles etc. As such, the average speed would be likely to be less than about 25 kph (15 mph). A narrow street would be considered to have residential properties within 2 m of the kerb, and buildings on both sides of the road.
The Local Authority has in recent years undertaken NO2 diffusion tube surveys at a number of locations which it felt may have fallen under this category, including Castle Street, Beaumaris, High Street, Menai Bridge and A5025 Benllech. On each occasion, the annual average NO2 level has been below the air quality objective and no further assessment has been required.
The Isle of Anglesey County Council confirms that there are no new/newly identified congested streets with a flow above 5,000 vehicles per day and residential properties close to the kerb, that have not been adequately considered in previous rounds of Review and Assessment.
3.2 Busy Streets Where People May Spend 1-hour or More Close to Traffic
Only NO2 needs to be considered for this particular assessment.
It is suggested in the Guidance that a busy street would have daily traffic flows (AADT) of around 10,000 vehicles / day or more. Individuals would also need to be exposed within 5m of the kerb for more than 1-hour or more.
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The Local Authority has in recent years undertaken NO2 diffusion tube surveys at a number of locations which it felt may have fallen within this category, including Castle Street, Beaumaris, High Street, Menai Bridge and London Road, Holyhead. During 2010/11 the Local Authority also examined a roadside location near Newry Beach, Holyhead; a popular promenade with green-space and covered seating areas overlooking Holyhead harbour (See Figure 3.1). The results for this location are document in Table 2.5 and the annual average for the entire 12 month study period of 11.47µg/m3, was significantly less than the air quality objective of 40µg/m3.
Figure 3.1: Covered seating area Newry Beach, Holyhead.
The Isle of Anglesey County Council has assessed newly identified busy streets where people may spend 1 hour or more close to traffic that have not previously been assessed and concluded that it will not be necessary to proceed to a Detailed Assessment.
LAQM USA 2012 37 Isle of Anglesey C.C. 3.3 Roads with a High Flow of Buses and/or HGVs.
This assessment needs to consider both NO2 and PM10.
The Guidance suggests that roads with high buses and/or HGVs would consist of those where such vehicles make up more than 20% of the traffic and where the HDV flow is greater than 2,500 vehicles per day. In addition, individuals would need to be exposed within 10m of these roads.
The Isle of Anglesey County Council confirms that there are no new/newly identified roads with high flows of buses/HDVs.
3.4 Junctions
This assessment needs to consider both NO2 and PM10.
The Guidance suggests the need to identify “busy” junctions with more than 10,000 vehicles per day and where there is a relevant exposure within 10m of the kerb.
The Isle of Anglesey County Council confirms that there are no new/newly identified busy junctions/busy roads.
3.5 New Roads Constructed or Proposed Since the Last Round of Review and Assessment
This assessment needs to consider both NO2 and PM10.
This assessment relates to new roads with a traffic flow greater than 10,000 vehicles per day or where traffic flow has increased on existing roads previously identified as having NO2 annual mean concentrations greater than 36 μg/m3, or more than thirty 24-hour exceedences of the PM10 objective of the 50 μg/m3.
It is recognised that the potential construction of a new nuclear power station at Wylfa, near Cemaes could create increased traffic flows upon the A5025 from
LAQM USA 2012 38 Isle of Anglesey C.C.
Cemaes to Valley, which may necessitate improvements to the road. In anticipation of the requirement for baseline NO2 data for the existing road, the Local Authority undertook a 12 month diffusion tube study at four locations along the A5025 during 2010/11. The 2011 results are document in Table 2.4, while the Non bias-adjusted results for 2012 are recorded at Appendix B.
In the event of any decision to construct a new nuclear power station at Wylfa and/or any proposals to alter the A5025 between Cemaes and Valley, a detailed assessment for both NO2 and PM10 would be required. In the interim, the Local Authority does not intend expand upon the work it has already completed or undertake a more detailed assessment at this time.
The Isle of Anglesey County Council confirms that there are no new/proposed roads.
3.6 Roads with Significantly Changed Traffic Flows
This assessment needs to consider both NO2 and PM10.
This assessment relates to new roads with a traffic flow greater than 10,000 that have experienced “large” traffic increases. The Guidance suggests that a “large” traffic increase would be more than 25%. A road at risk of exceeding the air quality objective can be taken to be one previously identified with an NO2 annual mean above 36μg/m3.
The Isle of Anglesey County Council confirms that there are no new/newly identified roads with significantly changed traffic flows.
LAQM USA 2012 39 Isle of Anglesey C.C. 3.7 Bus and Coach Stations
This assessment is required to consider the annual mean and 1- hour NO2 objectives.
The Guidance suggests the need to identify whether there are any relevant exposures within 10m of any bus station where the number of bus movements is greater than 2,500 per day.
The isle of Anglesey County Council confirms that there are no relevant bus stations in the Local Authority area.
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4 Other Transport Sources 4.1 Airports
This assessment needs to consider NO2.
The Guidance suggests the need to identify whether there are any relevant exposures within 1000m of an airport boundary. Furthermore, whether the existing background NOx is above 25 μg/m3 or the throughput of passengers and tonnes of freight in the most recent year possible is greater than 10 million passengers per annum.
Whilst there are no major airports on the Island, RAF Valley is a busy military airfield where pilots are trained to fly fast jets. The airfield is also home to a search and rescue operation/training unit. There are various publicly accessible car parks that lend themselves as viewing locations for the aircraft take-off/landings. During 2010/11 the local authority undertook a 14 month diffusion tube survey at one such location. Over 90% of the 12 month result was reported in the 2010 Air Quality Progress report, but three additional months in 2011 bring this figure to 100%. The highest annual mean NO2 level for 14 month study period was 7.91µg/m3, well below the 40µg/m3 air quality objective.
The Isle of Anglesey County Council confirms that there are no airports in the Local Authority area.
LAQM USA 2012 41 Isle of Anglesey C.C. 4.2 Railways (Diesel and Steam Trains)
The Guidance states that stationary locomotives, both diesel and coal fires, can give rise to high levels of sulphur dioxide (SO2) close to the point of emission. High levels of NO2 can also be experienced close to a railway line if there are sufficient numbers of trains.
4.2.1 Stationary Trains
The Guidance suggests that the Local Authority should identify locations where diesel or steam locomotives are regularly stationary for periods of 15 minutes or more. If this is the case, it should proceed to examine whether there is a potential for outdoor exposure of individuals within 15m of the stationary locomotive. Where there are three or more occasions a day when there might be a locomotive stationary with its engine running for 15 minutes or more a local authority is required to proceed to a detailed assessment.
Holyhead is the main terminus for the North Wales to Chester Railway Line. Many servicing facilities, including train washing, are present at the station and locomotives may be left running for 15 minute periods within short distances of the public bus stop and pavement on Victoria Road. From 8th May 2009 to 2nd May 2010 the Local Authority installed a UV Fluorescence SO2 Analyser in the former public toilets on Victoria Road, to monitor emissions from the stationary locomotives. Details of the monitoring were reported in the 2010 Progress Report. The data captured over the period of monitoring was over 92% and the highest 15 minute mean was 80μg/m3, significantly less than the air quality objective (266μg/m3, not to be exceeded more than 35 times a year).
The Isle of Anglesey County Council confirms that there are no locations where diesel or steam trains are regularly stationary for periods of 15 minutes or more, with potential for relevant exposure within 15m.
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4.2.2 Moving Trains
A list of railway lines that may have a large number of movements of diesel locomotives is included in Table 5.1 of the Guidance. This list does not include the Chester to Holyhead line.
The Isle of Anglesey County Council confirms that there are no locations with a large number of movements of diesel locomotives, and potential long-term relevant exposure within 30m.
4.3 Ports (Shipping)
The Technical Guidance advises that large ships generally burn oil with high sulphur content in their main engines (bunker oils). If there are sufficient movements in a port they can give rise to exceedences of the 15-minute objective for SO2. Auxiliary engines used while berthed (hotelling) usually use a lower sulphur fuel, and are unlikely to be significant. If shipping is using fuel with a sulphur content less than 1% then it will not be necessary to take the assessment further.
The Guidance requires a local authority to determine whether there are any relevant exposures within 250m of berths with 5,000 – 15,000 shipping movements per year or within 1km of berths with more than 15,000 movements per year. Holyhead is the main port in the UK serving Dublin and the main Ro Ro berths at Salt Island had approximately 5,500 ship movements in 2011. The HSS ferry operates from a separate berth (greater than 250m from Salt Island) and had fewer than 346 movements during the year.
The SO2 monitoring undertaken at Victoria Road, Holyhead from 8th May 2009 to 2nd May 2010 is approximately 350 metres from the HSS ferry berth. The Local Authority believes that Victoria road gives a good indication of the highest cumulative SO2 levels from port, rail, traffic and other local combustion sources affecting this area.
The Isle of Anglesey County Council confirms that there are no ports or shipping that meets the specified criteria within the Local Authority area.
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5 Industrial Sources 5.1 Industrial Installations
The Guidance advises that industrial sources are unlikely to make a significant local contribution to annual mean concentrations, but could be significant in terms of the short-term objectives. Particular attention should be paid to the combined impact of several sources, including those outside the local authority’s area. The assessment should consider all the regulated pollutants although those at most risk of requiring further work are SO2, NO2, PM10, and benzene.
5.1.1 New or Proposed Installations for which an Air Quality Assessment has been Carried Out
Normally in this section it would only be appropriate to consider proposed sources for which planning approval had been granted, however, the Local Authority believes that it is appropriate to explain its detailed assessment (during 2011/12) of a recent planning application for a combined heat and power biomass plant at the former Eastman Peboc site at the Llangefni Industrial estate. The Local Authority has refused planning permission for reasons including concerns about air quality and the company has submitted a formal appeal against the decision. The plant is also the subject of an application for an Environmental Permit under the Environmental Permitting (England and Wales) Regulations 2010, administered by Environment Agency Wales. A determination on the permit application was considered imminent at the time of writing. The Planning Application resulted in the Local Authority commissioning an expert opinion and air quality monitoring in the Llangefni Area during 2011 and 2012. The Local Authority believes it would be inappropriate not to refer to the detailed assessment, undertaken as part of this process, given that this formed a significant part of its LAQM work in 2011 and early 2012.
In 2011 EcoPellets Ltd submitted a planning application to the Local Authority to operate a wood pelleting plant, liquid biomass CHP Plant and solid biomass CHP plant adjacent on the former Eastman Peboc site at the Llangefni Industrial estate.
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The solid biomass CHP plant is described as providing process heat for the wood pellet plant and to generate approximately 17MWe of renewable electricity, of which 14.3MWe will be available for export to the grid. The Liquid biomass CHP plant will utilize tallow and recovered vegetable oils to provide process heat for the wood pellet plant and to generate approximately 14MWe of renewable electricity, of which 13.6MWe would be available for export to the grid.
The pelleting plant would produce about 100,000 tonnes per annum of wood pellets for use in a wide range of combustion appliances from domestic to power station scale. The wood pellets would be manufactured from timber which it is claimed will be sourced in the North Wales and England.
The biomass CHP plants have a combined generating capacity of about 31MWe which the applicant states will be exported to the local electricity distribution network. As the CHP plants will burn recycled wood sourced locally, and a liquid biomass consisting of vegetable oils and fats, an A1 permit has been sought under the Environmental Permitting (England and Wales) Regulations 2010. A report dated the 24th February 2012, prepared by the applicant, detailed the outcome of air quality dispersion modeling for the plant. The document was one of a succession of reports with the latest version taking into account revised emission limit values [ELVs] for Nitrogen Dioxide [NO]. The report had been required by the Environment Agency as part of a formal system requiring additional information to enable it to assess the permit application. The revisions produced reductions in the estimates concentrations of NO2 compared to earlier reports submitted with the planning application. The following table outlines the predicted highest concentrations for the principal pollutants of concern for local air quality, excluding carbon monoxide, which was likely to be of little significance. Table 5.1: Principal emissions from proposed CHP Biomass Plant. Air Quality Objective PEC1 % of AQS Grid Reference 3 µg/m
Maximum hourly average NO2. 166 83 246700,374660 Maximum annual average NO2. 27.8 70 246700, 374660 rd 99.73 % of hourly average SO2. 134 38 246700, 374620 th 99.18 % of 24hr average SO2. 85 68 246700, 374620 th 99.9 % of 15 minute mean SO2. 149 56 246660, 374620 90.41 % of 24hr average PM10. 37 74 246420, 374900 Annual average PM10. 20.4 51 246420, 374900
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The Local Authority was primarily concerned about the predicted NO2 and PM10 concentrations and what it perceived as an over-reliance upon the use of the background maps to estimate long term and in particular, short term background concentrations for both pollutants.
The Background concentration for NO2 from the background maps and centred upon grid square 246500, 374500 was estimated to be 13.2µg/m3 for 2008 and this figure was used in the air quality modelling report. It was predicted that the maximum hourly process contribution was likely to be 140µg/m3 without taking into account the background. Given that the only annual average background level available was that from the background maps, the level of 13.2ug/m3 was doubled to allow for the inevitably higher value for the hourly average background. Based on this, the th modelling predicted the 99.79 percentile of maximum NO2 hourly average Predicted Environmental Concentration [PEC] to be 166ug/m3 (83% of the 200ug/m3 objective). This was at a location 150m to the east of the plant at grid reference SH246700, 374660 and within the neighbouring industrial estate. The nearest local residential premises lie approximately 250m to the east of the site. While these are the most sensitive receptors for the purpose of the longer term objectives, such as the annual or daily average, there are several commercial and retail businesses on the industrial estate where shorter term objectives would apply.
Numerous car showrooms, veterinary clinics and the Council’s business centre are located on the industrial estate. The nearest car showroom is 250m to the northwest, while the Council’s business centre is approximately 150m to the northeast. Since the industrial estate was recently extended, many plots remained un-developed. A 3.37 acre plot [C1] borders the proposed Biomass plant to the northeast and this plot is within 50m of grid reference SH246700, 374660 the estimated location of the maximum hourly average NO2 concentration. Potentially, any location within the industrial estate, particularly near undeveloped plots, had the potential for short-term exposure up to 1hour.
Box 6.3a of the Technical Guidance [TG.09] suggests that if the predicted increase in the 99.8%ile of NO2 is more than 75% of the available headroom (the difference between the objective and background), a more detailed assessment will be
LAQM USA 2012 46 Isle of Anglesey C.C. required. Assuming that twice the annual average background NO2 level available from the background maps equates to the 99.8th percentile of background NO2 (i.e. 26.4ug/m3) this allows an available headroom of 173.6µg/m3. Consequently, 75% of this headroom would be 130.2µg/m3 or 156.6µg/m3 when the background is taken into account, so a PEC of 166ug/m3 is above this level.
Paragraph A3.205 of the Technical Guidance states that the approach outlined above:-
“….is likely to be conservative compared to adding hour by hour predictions with hour by hour background. Where this approach suggests that the concentrations
exceed 75% of the air quality objectives (equivalent to 150 μg/m3) a more detailed assessment will be required, which may include the consideration of variable hourly emissions (as opposed assuming continuous operations), and/or the addition of hour by hour background to hour by hour predicted process contributions. However, the approach presented above is suitable for the detailed assessment of point sources as part of review and assessment.”
nd On the 2 November 2011, the Local Authority began a 12 month NO2 diffusion tube survey near the closest car showroom on the industrial estate. Early indications reveal that the annual average may be similar to that contained within the background maps (non-bias corrected results for 2012 contained in Appendix B), but it is not possible to estimate what the shorter term hourly concentrations may be. The modelling predicted that the highest annual average NO2 process contribution would be 14.6µg/m3. When the estimated annual average background concentration is taken into account, this equates to a predicted environmental concentration of 27.8ug/m3 or 70% of the annual objective of 40ug/m3.
The Local Authority believes that there is an uncertainty with regard to the predicted shorter term hourly concentrations because of the over-reliance on the background maps to estimate the short term hourly background concentrations. The predicted 99.79th percentile of maximum hourly averages is also significantly greater than the 75% headroom detailed in TG(09).
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The Applicant has used a similar approach for the assessment of PM10 and in the absence of local data used an annual background concentration of 12µg/m3, based upon the Background Maps for 2008.
According to the Air Quality Modeling report dated the 27th February 2012, the maximum daily average process contribution during normal operations is predicted to be 25µg/m3 which when considered with the background level, would give a maximum 90.41tst percentile of 24-hourly average PM10 PEC of 37ug/m3, 74% of the 50ug/m3 objective. Similarly, the maximum PM10 annual average process contribution was 8.4µg/m3, giving a maximum annual average PEC of 20.4µg/m3, or 51% of the 40µg/m3 objective. The maximum reported values are predicted to occur at a location about 50 metres to the north-west of the site within the industrial estate at grid reference 246420, 374900 not far from the Council’s business centre.
In June 2011 the Local Authority installed a Turnkey Osiris PM10 monitor on the roof of Llangefni Library to determine the background concentration of the pollutant. The results for 2011 are reported in table 2.6 and 2.7. The results for the extended period 1 September 2011 to 31st August 2012, (based upon a capture rate of 86.3%) indicate only slight variation to those reported earlier, with an annual average of 16.6µg/m3 and 90th percentile of 26.9µg/m3. Only one exceedence of the 24hr objective occurred, due to an incident of Saharan Dust on the 10th October 2011. A previous co-location study has shown good correlation between the Osiris and the Partisol and applying a correction of x1.3 would significantly over-estimate the concentrations of PM10 in this locality.
It is apparent from the measured results that the predicted background concentration of 12µg/m3 from the background maps significantly under-estimates the PM10 levels in Llangefni. When assessing the impact of the 90.4th percentile of the 24hr mean Process Contribution on backgrounds, the Annex 3.207 of the Technical Guidance advises that (unlike in the case of NO2) the annual average background is not doubled in order to take into account the shorter time period and the process contribution is merely added to the annual mean background level.
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Box 6.3b of the Technical Guidance [TG.09] suggests that if the predicted increase in the 90.4th percentile is more than 50% of the available headroom (the difference between the objective and background), then a more detailed approach will be required.
If the measured annual mean [16.6µg/m3] is used, rather than the annual average derived from the background maps, this allows available headroom of 33.4ug/m3 for the 90.4th percentile of the 24hr mean. Consequently, 50% of this headroom would be 16.7ug/m3 or 33.3ug/m3 when the background is taken into account. Therefore, a PEC of 41.6ug/m3 is above this level, as is the applicant’s own PEC of 37ug/m3.
Paragraph A3.208 of the Technical Guidance states that the approach outlined above:-
“….The approach described above is likely to be conservative compared to adding hour by hour predictions with hour by hour background. Where this approach suggests that the predicted increase in the …90th percentile above the background is more than 50% of the available headroom (the difference between the objective and background), then a more detailed assessment will be required. This may include the consideration of variable hourly emissions to further refine the source contributions, and/or the addition of hour by hour background to hour by hour predicted process contributions. However, the approach presented above is suitable for the detailed assessment of point sources as part of review and assessment.”
With regard to the annual mean, if this were to be determined on the basis of the measured PM10 level, the predicted environmental concentration would be 25ug/m3 rather than the 20.4ug/m3 suggested by the applicant. The maximum reported annual mean was predicted to occur at a location about 50 metres to the north-west of the site within the industrial estate at grid reference 246420, 374900 where there are currently no residential properties.
The Local Authority has expressed uncertainty regarding existing (NO2 and PM10) background levels and the development’s intention to use a significant proportion of
LAQM USA 2012 49 Isle of Anglesey C.C. the available headroom. These issues form part of its grounds for refusal of planning permission. The Local Authority has particular concern about the 99.79th percentile of hourly NO2 and 90.4th percentile of the 24hr mean PM10 level on the nearby industrial estate. Should this development be successful in its appeal, a more detailed assessment may be required, but in the meantime, the Local Authority considers the actions it has undertaken sufficiently addresses the detailed assessment processes required for the purposes of the planning process.
The Isle of Anglesey County Council has assessed new/proposed industrial installations and concluded that it will not be necessary to proceed to a Detailed Assessment.
5.1.2 Existing Installations where Emissions have Increased Substantially or New Relevant Exposure has been introduced
The Isle of Anglesey County Council confirms that there are no industrial installations with substantially increased emissions or new relevant exposure in their vicinity within its area or nearby in a neighbouring authority.
5.1.3 New or Significantly Changed Installations with No Previous Air Quality Assessment
In 2009 an in-vessel composting plant was commissioned near to the civic amenity site at Penhesgyn, near Menai Bridge. The composting plant processes organic material from green and kitchen waste collections from Anglesey, Gwynedd and Conwy Councils.
Oversized waste materials such as large foliage, twigs or branches arrive on site and are shredded in order to reduce them to a size suitable for composting. The material may be blended with other compostable material before being loaded into the composting tunnels, where it will stay for 5 – 7 days. The facility has five 5 tunnels, each 30m x 5.5m x 6.3m (length, height, width) and the composting process is computer controlled to ensure optimum composting conditions. Once removed from
LAQM USA 2012 50 Isle of Anglesey C.C. the tunnels the material is placed in a maturation area consisting of stockpiles 4 – 6m high.
Figure 5.1 Photograph of compost storage area at the Composting Plant, Penhesgyn.
The maturation process will last for approximately 14 – 16 weeks. At the end of the composting process the compost is screened into various sizes.
The Document Monitoring of particulate matter in ambient air around waste facilities [Technical Guidance Document (Monitoring) M17]2 produced by the Environment Agency in March 2004 identifies composting plants as potential sources of particulate matter. The airborne particulate matter from composting plants is identified by the Technical Guidance M17 as being primarily coarse in nature and derived from mainly organic based material which may include micro-organisms such as fungi, molds, spores and bacteria (often attached to the cellulose-based material).
The suspended particles can range in size from 0.5 to 100µm, which means that some of the particles will fall within the 10µm limit of PM10. Using enclosed or in- vessel systems is identified in Technical Guidance M17 as being one of the control measures that can be employed to control particulate matter from composting plants.
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The nearest residential property is approximately 130m to the south west of the main building housing the composting tunnels, upwind of the prevailing wind direction. Nevertheless, in the summer of 2011 the Environmental Health Section decided to conduct a 12 month study, partly funded by the Authority’s waste Management Section, to examining levels of PM10 at the site. Monitoring commenced on the 7th October 2011 and the instrument’s results were uploaded daily onto the Welsh Air Quality Web site11. The results for 2011 are detailed in tables 2.6 and 2.7.
A Turnkey Osiris PM10 monitor was used for the study and was installed on the closest part of the main composting tunnel roof to the residential property. Various locations were considered, but this was judged to represent the worst-case situation when the wind was blowing in the direction of the property.
During the period 8th October 2011 to 10th September 2012 the instrument had a 90.4% capture rate. A single exceedence of the air quality standard (50µg/m3) occurred on the 2nd April 2012, when a daily average of 55.6µg/m3 was recorded. No correction has been applied to the results as the dust particles in question were coarse in nature and previous collocation studies undertaken by the Council show a good correlation with the European reference method, the Partisol. The annual average PM10 level was 14.8 µg/m3, which is amongst one of the lowest levels recorded by the Council using these instruments, but higher than the 9.87 µg/m3 (2012) level quoted in the background maps for grid reference 253500, 374500. The 90th percentile of daily average was 24.7µg/m3, which is less than the 50 µg/m3 24hr objective for this pollutant.
The Isle of Anglesey County Council has assessed new industrial installations, and concluded that it will not be necessary to proceed to a Detailed Assessment.
LAQM USA 2012 52 Isle of Anglesey C.C. 5.2 Major Fuel (Petrol) Storage Depots
This assessment needs to consider Benzene.
The Guidance advises the local authority to identify any major fuel storage depots handling petrol within its area.
There are no major fuel (petrol) storage depots within the Local Authority area.
5.3 Petrol Stations
The Guidance advises that some petrol stations have the capability to emit sufficient benzene to cause a risk of exceedance of the 2010 objective for benzene.
Local Authorities are required to identify petrol stations with an annual throughput of petrol more than 2000m3 and with a busy road with more than 30,000 vehicles nearby. In such instance, if there is a relevant exposure within 10m of the pumps a detailed assessment is required.
The Isle of Anglesey County Council. confirms that there are no petrol stations meeting the specified criteria.
5.4 Poultry Farms
This assessment needs to consider PM10.
Local Authorities are required to identify any farms housing in excess of 400,000 birds if mechanically ventilated, 200,000 birds if naturally ventilated and 100,000 birds for any turkey unit. In such instances where there are relevant exposures within 100m of the poultry unit, a detailed assessment is required.
Vion UK operate a number of poultry farms, scattered around the Island, with up to 198,700 places for rearing chickens. The farms were built at a similar time and the
LAQM USA 2012 53 Isle of Anglesey C.C. wooden sheds are of a similar design, with roof mounted mechanical vents. Following concerns from local residents about dust from a nearby chicken farm, the Local Authority operated a Turnkey Osiris PM10 monitor at “Parc”, Penlon, Newbrough from the 4th March 2003 to 31st March 2007. Situated near the boundary of the farm and less than 60m from the nearest poultry shed, “Parc” was one of the closest domestic premises to a poultry farm on the island. The PM10 monitoring results for this location have been discussed in detail in the Updating and Screening Assessment in 2006 and the progress report for the period 2006/07. The results were consistently below the Welsh Government’s 24 hour mean objective of 50μg/m3 not to be exceeded on more than 35 days per year. During its final year of operation from 1st April 2006 to 31st March 2007, the instrument was operational for 99% of the time and reported an annual mean of 27.4μg/m3 with 17 exceedences of the 24hr mean. In addition, the Environment Agency conducted their own monitoring at the site from the 19th June – 15th October 2003 using a Mobile Monitoring Facility containing a TEOM PM10 monitor. The mean PM10 level was 25.3 μg/m3 and four exceedences of the 24hr mean objective occurred during the measurement period.
A full list of all those farms permitted under the Integrated Pollution Prevention Control system is included at Appendix C.
The Isle of Anglesey County Council has assessed the poultry farms meeting the specified criteria and concluded that it will not be necessary to proceed to a Detailed Assessment.
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6 Commercial and Domestic Sources 6.1 Biomass Combustion – Individual Installations
In September 2011 the Environmental Health Section received a planning consultation for the construction of an energy centre for a 600kW biomass boiler at Tre Ysgawen Hall, Capel Coch. The chimney height of the boiler was 8m above ground level, but the ground was higher on one side reducing the overall height above ground level to 4.5m, approximately 3.5m of which was above the highest part of the building. The fuel to be used was low sulphur (typically 0.1%), the stack diameter was 300mm and exit velocity of the gas 2.9m/s.
A screening assessment was undertaken to determine the likely impact of the biomass boiler on local air quality. The 24 hour objective for PM10 and the 1 hour objective for NO2 were considered to be the principal pollutants of concern and the receptors would be guests visiting the hotel.
The Technical Guidance [TG(09) section 5.74 – 5.86] together with the Technical Guidance [Screening Assessment for Biomass Boilers 9July 2008)], enabled the Local Authority to determine whether a predicted calculated “background-adjusted” emission rate was greater than a “threshold emission rate” obtained from nomographs.
The following information was collated:- Description of the combustion appliance. Height of stack above ground. Diameter of the stack. Dimensions of buildings within a distance of five times the stack height above ground. Maximum emission rates of particulate matter and oxides of nitrogen based upon emission factors for solid fuel combustion in Appendix 1 of the Screening Assessment for Biomass Boilers. The estimated background pollutant concentrations from background maps centred upon the nearest 1km x 1km grid square.
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The nomographs did not contain a plotted line which corresponded to the 300mm diameter chimney which was to be used. Nevertheless, it is possible to interpolate the result based upon the plotted lines for 200 and 500mm diameter chimneys. The following table provides a summary of the results.
Pollutant Background Pollutant Background Threshold Threshold SH244500, emission Adjusted emission emission 381500 rate. Emission 200mm 500mm rate [g/s]. diameter diameter stack stack PM10 24hr 9.72µg/m3 0.0396 g/s. 0.00177737 0.002 0.003
NO2 1hr 4.296µg/m3 0.09 g/s. 0.0188079 0.025 0.04 Table 6.1: Summary of results for biomass boiler at Tre Ysgawen Hall, Capel Coch.
As the background adjusted emission rate for both the PM10 24hr and NO2 1hr objectives were not greater than the interpolated threshold emission rate for a 300mm diameter stack, the Local Authority does not need to proceed to a more detailed assessment. As part of the planning condition, the hotel was required to undertake a 12 month NO2 diffusion tube survey as a simple verification measure once the boiler was operational. The monitoring commenced at the end of April 2012 and early indications are that monthly average NO2 levels are very low. The non bias-adjusted results are included at Appendix B.
The isle of Anglesey County Council has assessed the biomass combustion plant, and concluded that it will not be necessary to proceed to a Detailed Assessment.
LAQM USA 2012 56 Isle of Anglesey C.C. 6.2 Biomass Combustion – Combined Impacts
The assessment needs to consider PM10.
The Local Authority is not aware of any areas where there is widespread use of biomass combustion appliances which could in combination lead to unacceptable high PM10 concentrations.
The Isle of Anglesey County Council confirms that there are no combined impacts from biomass combustion plants in the Local Authority area.
6.3 Domestic Solid-Fuel Burning
This assessment needs to consider sulphur dioxide.
The Local Authority has considered areas of significant coal burning in previous reviews and concluded that it was not necessary to proceed to a more detailed assessment for SO2.
The Isle of Anglesey County Council confirms that there are no areas of significant domestic fuel use in the Local Authority area.
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7 Fugitive or Uncontrolled Sources
This assessment needs to consider PM10.
The Local Authority is required to establish whether there is a relevant exposure “near” to a source of fugitive dust. A relevant exposure is considered to be within:-
1000m for a background greater than 28μg/m3. 400m for a background greater than 26μg/m3. 200m for any other background level.
The distances are from the source, which may not always coincide with the boundary of the site. If there are recent complaints about dust or visual inspection indicates significant dust emissions or dust tracked out of the site onto public roads then a more detailed assessment is required.
During the last twelve months the Local Authority has been undertaking PM10 monitoring at three fugitive emission sources:-
Gwyndy Quarry, Llandgrygan. Rhuddlan Bach Quarry, Brynteg. Former Sedimentation Ponds, Parys Mountain.
The results from these studies have been discussed earlier in Table 2.6, 2.7 and 2.8. The results indicate that there is little likelihood of the air quality objectives for PM10 being exceeded at these locations.
The Isle of Anglesey County Council confirms that there are no potential sources of fugitive particulate matter emissions in the Local Authority area.
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8 Conclusions and Proposed Actions
8.1 Conclusions from New Monitoring Data
The Local Authority has continued managing the PM10 monitors at Llynfaes and Brynteg on behalf of the nearby quarry operators. Both sites continue to be within the air quality standard for PM10.
In June 2011 the Local Authority installed a Turnkey Osiris PM10 monitor on the roof of Llangefni Library to determine the background concentration of the pollutant within the town. The results for 2011 are reported in table 2.6 and 2.7. The results for the extended period 1 September 2011 to 31st August 2012, (based upon a capture rate of 86.3%) indicate an annual average of 16.6µg/m3 and 90th percentile of 26.9µg/m3. Only one exceedence of the objective occurred, namely the 10th October 2011, which has been attributed to Saharan dust. A similar exceedence occurred at Llynfaes and Brynteg on this day.
During the 2011 the Local Authority installed a Turnkey Osiris PM10 monitor at the Composting site at Penhesgyn. Although the data capture for 2011 was only 22%, the Local Authority is able to report the data up to 10th September 2012. The additional data ensures a capture rate of over 90%. The annual average PM10 level was 14.8µg/m3, which is amongst one of the lowest levels recorded by the Council. The 90th percentile of daily average was 24.7µg/m3, which is less than the 50 µg/m3 24hr objective for this pollutant. The Local Authority has concluded that there is no further action required and intends to withdraw the instrument from this site.
During 2011 the Local Authority concluded its dust deposit monitoring at 3 properties near the Henwaith settlement ponds, Parys Mountain. The annual deposit rates for the Cerrig Bleiddiau, Pen y Corn and Tai Fry were well within the typical deposition rates normally quoted for rural areas, resulting in the deposit gauges being removed from these properties at the end of August 2011. The deposit gauge at Henwaith showed a significant reduction in deposited dust since the completion of the remedial
LAQM USA 2012 59 Isle of Anglesey C.C. work. Levels at this property remain slightly higher than the others, particularly during periods of long dry conditions and a further 12 months monitoring was considered desirable.
The NO2 diffusion tube results for the kerbside of the A55(T) at Llanfair P.G. remain the only location where the Welsh Government’s annual objective of 40μg/m3 is exceeded on the island. The closest property is approximately 20m from kerbside, where it is estimated that the concentration would be 21.9μg/m3. Nevertheless, the NO2 diffusion tube location at Llanfair P.G. is situated adjacent to an authorised lay- by with no time restriction on its use. Consequently, the 1 hour objective of 200μg/m3 (which is not to be exceeded more than 18 times a year) would apply. While the annual mean remains below 60μg/m3, the 1 hour mean objective for NO2 is unlikely to be exceeded. Since 2005, there has been a steady increase in annual mean NO2 levels at this location, but, a marked drop in 2011 took levels back to those last seen in 2008. The Local Authority will continue to monitor NO2 using diffusion tubes at this location for the foreseeable future.
8.2 Conclusions from Assessment of Sources
The Local Authority has previously undertaken a number of assessments at congested or busy streets where the public are likely to be within close proximity. None of these studies to date have indicated a likelihood of an exceedence of the Air Quality Objective for NO2. During 2011 the Local Authority undertook additional monitoring at Newry Beach, Holyhead; a popular promenade overlooking Holyhead harbour. The annual average for the entire 12 month study period was 11.47µg/m3, significantly less than the air quality objective of 40µg/m3. No detailed assessment was required and Local Authority has ceased monitoring at this location
During 2011/12 the Local Authority also undertook a 14 month diffusion tube survey at RAF Valley. The highest annual mean NO2 level for 14 month study period was 7.91µg/m3, well below the 40µg/m3 air quality objective. No detailed assessment was required and Local Authority has ceased monitoring at this location
LAQM USA 2012 60 Isle of Anglesey C.C. 8.3 Proposed Actions
The Local Authority intends to prepare an air quality progress report in 2013. The report will detail the results of the on-going studies including the NO2 diffusion tube monitoring at Tre Ysgawen Hall, Capel Coch, the dust monitoring at Henwaith Settlement Ponds Parys Mountain and the NO2 diffusion tube monitoring at Llangefni Industrial Estate. It is anticipated that PM10 monitoring will continue for the foreseeable future at both Llynfaes and Brynteg, however, PM10 monitoring at Llangefni and Penhesgyn is likely to cease during 2012. No decision has been taken to date on relocating the monitors to another site.
In 2012, the Local Authority also intends to undertake dust deposit gauge monitoring at 3 locations around the existing Wylfa Nuclear power station. The purpose of the monitoring is to establish background dust deposition levels in the event of a decision to construct another nuclear power station on the site.
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9 References
1. Isle of Anglesey County Council – Local Air Quality Web Site:- http://www.anglesey.gov.uk/planning-and-waste/environmental- health/pollution/air-quality/
2. Monitoring of particulate matter in ambient air around waste facilities – Technical Guidance Document (Monitoring) M17: Environmental Agency (March 2004).
3. DEFRA’s Local Air Quality Management Support website latest information on diffusion tube bias for each laboratory. Available at:-National Bias Adjustment factors accessed on 8th October 2012 at:- http://laqm.defra.gov.uk/bias-adjustment-factors/national-bias.html
4. DEFRA’s Local Air Quality Management Support website information on the precision of diffusion tubes for each laboratory. http://laqm.defra.gov.uk/diffusion-tubes/precision.html
5. Summary of Laboratory Performance in WASP NO2 Proficiency Testing Scheme for Rounds 108-115. Accessed 8th October 2012 at:- http://laqm.defra.gov.uk/documents/WASP-Rounds-108-115-(January-2010- December-2011).pdf
6. A Calculator which estimates the annual mean nitrogen dioxide concentration at one distance form a road, using measurements made at a different distance from the same road. Available from DEFRA’s Local Air Quality Management Support website at:- http://laqm.defra.gov.uk/tools-monitoring-data/no2-falloff.html
7. Background concentrations for each 1 x 1km grid for each local authority area with projections for each year up to 2020. Available at:- http://laqm.defra.gov.uk/review-and-assessment/tools/background-maps.html
8. Local Air Quality Management Technical Guidance Document LAQM.TG(09). Available at:- http://archive.defra.gov.uk/environment/quality/air/airquality/local/guidance/doc uments/tech-guidance-laqm-tg-09.pdf
9. Management, mitigation and monitoring of nuisance dust and PM10 emissions arising from the extractive industries: an overview. Report to the Mineral Industry Research Organisation (MIRO) February 2011. Available at:- http://www.sustainableaggregates.com/library/docs/mist/l0091a_ma_7_g_2_0 06.pdf
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10. The Protocol for using the dry Frisbee (with foam insert) dust deposit gauge. Available at: http://www.hanby.co.uk/frisbeeprotocol.pdf
11. Welsh Air Quality Web site:- http://www.welshairquality.co.uk/index.php
12. Technical Guidance [Screening Assessment for Biomass Boilers] (9July 2008) available at:- http://uk-air.defra.gov.uk/reports/cat18/0806261519_methods.pdf
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Appendices
Appendix A: QA:QC Data
Diffusion Tube Bias Adjustment Factors
The Local Authority has used Nitrogen Dioxide (NO2) diffusion tubes supplied by Environmental Scientifics Group, Oxford. The tubes use a preparation of 50% Triethanolamine (TEA) in water. This bias has been corrected using “bias adjustment factors” calculated from spread sheets available from the Review and Assessment web site. The latest spread sheet was used for the purpose of this Updating and Screening Assessment (v07/12)3 and the bias adjustment factor of 0.84 was used to correct the 2011 diffusion tube data.
Discussion of Choice of Factor to Use
A “bias adjustment factor” calculated from a spread sheet available from the Review and Assessment web site (v07/12) has been used.
PM Monitoring Adjustment
The Local Authority has discussed the co-location of an Osiris monitor and a Partisol Instrument at Llynfaes and TEOM at Penlon in previous reports and has explained that where dust is of a coarse fraction an adjustment of x1.3 would lead to a significant overestimation using these monitors.
Short-term to Long-term Data adjustment
No short term to long term adjustment has been undertaken by the Local Authority, as a minimum of 12 months is chosen for study periods. Where less than 9 months data has been reported in any year, either the result has been deferred until the next year or following year results have been included (where available).
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QA/QC of automatic monitoring
As part of its normal QA/QC procedure, the Local Authority undertakes routine filter changes and air flow checks (600ml/min) on the Turnkey Osiris instruments normally on a quarterly basis. This is in addition to an annual service and calibration undertaken by Turnkey instruments under the terms of a service contract. The data is downloaded electronically from each of the instruments approximately 2 – 3 times a week using a GSM modem. This enables the performance of the instrument to be monitored and enables problems to be rectified quickly and with minimum loss of data. The data is stored as 15 minute averages and is analysed using a dedicated software system (AirQ32). A visual data ratification process is employed, to safeguard against erroneous peaks etc., before any results are reported.
QA/QC of diffusion tube monitoring
It is noted that Environmental Scientifics Group have participated in all WASP5 rounds R112 – R115 which have occurred during 2011 and 100% of the results submitted were determined to be satisfactory.
ESG’s precision results for collocated NO2 Diffusion Tubes were rated as “Good Precision” in 20114. Precision reflects a laboratory’s performance/consistency in preparing and analysing those tubes used in a collation study to determine diffusion tube bias, as well as the subsequent handling of the tubes in the field.
LAQM USA 2012 65 Isle of Anglesey C.C. Appendix B: Diffusion Tube Data Set.
2010 (μg/m3) Bias Corected. Newry Beach, Holyhead. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 9.6 17.8
2011 (μg/m3) Bias Corrected. A55(T) Llanfair P.G. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 52.21 45.07 48.14 45.32 43.91 31.54 42.08 43.74 40.92 48.22 52.12 42.16
Newry Beach, Holyhead. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 15.52 17.18 17.51 12.28 7.8 6.89 6.89 8.47 6.47 11.21
Llanfachraeth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 8.72 4.73 5.56 7.72 7.97 M 7.22 M 6.14
Llanfaethlu Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 7.22 5.31 4.57 5.31 5.56 5.31 6.64 8.80 7.14
Tregele. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 5.73 7.14 4.73 4.23 5.4 7.22 6.47 8.63 5.89
Cemaes Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 6.47 6.64 5.40 5.48 5.81 4.73 8.30 10.54 8.47
Llangefni Industrial Estate. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 13.61 8.88
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2012 (μg/m3) Non Bias Corrected. Llanfachraeth Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 7.4 M 13.6
Llanfaethlu Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 8.6 11.8 11.9
Tregele. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 7.1 12.5 12.1
Cemaes Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 10.2 9.7 12.6
Llangefni Industrial Estate. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 10.7 14.3 11.9 8.9 10.1 7.7 20.6 7
Tresgawen Hall. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 6.7 6.8 6 5.9 4.3
LAQM USA 2012 67 Isle of Anglesey C.C. Appendix C: Maps of diffusion tube locations.
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LAQM USA 2012 76 Isle of Anglesey C.C. Appendix D: PM10 Exceedences.
Exceedences of the 24 hour Objective at Llynfaes
1st January 2011 – 31st December 2011. Pollution Date PM10 Event Concentration µg/m3 1 10th October 61.5 2 26th December 51.7 3 9th October 50.1
Exceedences of the 24 hour Objective at Brynteg
1st January 2011 – 31st December 2011. Pollution Date PM10 Event Concentration µg/m3 1 5th May 78.7 2 29th March 72.1 3 10th October 61.6 4 26th March 53.5 5 31st March 52.2
Exceedences of the 24 hour Objective at Llangefni
1st January 2011 – 31st December 2011. Pollution Date PM10 Event Concentration µg/m3 1 10th October 62.8
Exceedences of the 24 hour Objective at Penhesgyn
1st January 2011 – 31st December 2011. Pollution Date PM10 Event Concentration µg/m3 None - -
LAQM USA 2012 77 Isle of Anglesey C.C. Appendix E: List of Poultry Rearing Units.
1. Awel Deg, Llandrygarn: SH51016, 75900 2. Awelon, Rhoscefnhir: SH51003, 75911 3. Bron Afon, Llandyfrydog: SH44033, 85013 4. Gernant, Bryngwran: SH34558, 76264 5. Glan Dwr, Llanddaniel: SH50540, 71532 6. Gwynt y Môr, Bryngwran: SH35801, 76382 7. Morlais, Newborough: SH41677, 69791 8. Minafon, Cerrigceinwen: SH41378, 74589 9. Swn y Don, Trefdraeth: SH41677, 69791 10. Swn y Gwynt, Bodffordd: SH42000, 75700
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