Dust Assessment Weavers Hill Quarry, Aqualate Estate

Dust AssessmentWeavers Hill Quarry, Aqualate

Estate, Staffordshire, UK

Prepared for:

Traxx (Aggregates) Limited

Prepared by: ENVIRON UK Limited

Birmingham, UK

Date: August 2009

Project Number: UK15-14343

Contract/Proposal No: UK15-14343

Issue: 2

Author: James Magor (signature):

Project Manager/Director: Matt Royall (signature):

Date: August 2009

This report has been prepared by ENVIRON with all reasonable skill, care and diligence, and taking account of the Services and the Terms agreed between ENVIRON and the Client. This report is confidential to the client, and ENVIRON accepts no responsibility whatsoever to third parties to whom this report, or any part thereof, is made known, unless formally agreed by ENVIRON beforehand. Any such party relies upon the report at their own risk.

ENVIRON disclaims any responsibility to the Client and others in respect of any matters outside the agreed scope of the Services.

VERSION CONTROL RECORD Issue Description of Status Date Reviewer

Initials Authors Initials

A First Draft 03/04/09 MDR JM

1 First Client Issue (Draft) 06/04/09 MDR JM

2 Second Client Issue (Draft) 17/08/09 MDR JM


Air Quality Assessment Weavers Hill Sand Pit

UK15-14343 Issue: 2 (Draft)

Contents Page

1 INTRODUCTION 1 1.1 Introduction 1 1.2 Scope 1 1.3 Methodology 1 1.4 Limitations 1

2 SITE DESCRIPTION 3 2.1 Site Location and Setting 3 2.2 Existing Site Description 4 2.3 The Proposed Development 5

3 LOCAL AIR QUALITY AND ASSESSMENT CRITERIA 6 3.1 Local Air Quality Management 6 3.2 Dust Deposition and PM10 6 3.3 Expected Air Quality at the Development Site 7

4 IDENTIFICATION OF POTENTIAL IMPACTS 9 4.1 Sources of Dust – Construction 9 4.2 Sources of Dust – Operational Activities 9 4.3 Dust Deposition 9 4.4 Receptors 10

5 CONTROL OF DUST 13

6 CONCLUSION 14 Annex A: Greenfield Associates drawing (ref: WHQ Extraction Design 74m)



UK15-14343 Issue: 2 (Draft) 1 of 14

1 INTRODUCTION

1.1 Introduction ENVIRON UK Ltd (ENVIRON) was commissioned by Traxx (Aggregates) Limited, ‘the Client’, to carry out a dust assessment for a proposed sand extraction works at Weavers Hill Quarry, Aqualate Estate, Nr. Gnosall, Staffordshire. Staffordshire County Council (the County Planning Authority), has requested an assessment regarding the potential effects of the proposed sand extraction works on local air quality, in particular the potential effects of dust on the nearby Aqualate Mere Site of Special Scientific Interest (SSSI).

This report examines the outline implications for air quality arising from the proposed development. Potential sources of dust emissions are identified and are placed in the context of existing air quality and emission sources, as well as being considered in the context of locally sensitive receptors.

1.2 Scope The key issues relating to air quality are considered to be:

dust generated by the proposed sand extraction operations; and

dust generated as a result of vehicles accessing the proposed development.

1.3 Methodology ENVIRON understand the proposed extraction area will be as per Greenfield Associates drawing (ref: WHQ Extraction Design 74m), included as Annex A. It is understood the proposed development will comprise a sand extraction works with an access road, a weighbridge and a site office. ENVIRON has therefore considered potential sources of dust, which may potentially arise from a sand extraction works.

The assessment has been carried out in the following stages. First, existing air quality in the vicinity of the development site has been derived. Second, potential sources of dust and locally sensitive receptors have been identified. Third, impacts of the identified emissions on existing air quality have been predicted and, where necessary, appropriate mitigation measures have been proposed.

1.4 Limitations This assessment focuses on specific issues relevant to the proposed development, such as potential for dust generation, proximity of potentially sensitive receptors and dust mitigation measures. No site specific ambient air quality monitoring was carried out as part of the assessment. In addition, dust has not been considered in relation to the occupational exposure of site personnel. ENVIRON understands this will be undertaken by the Client.




The assessment considers the potential for dust generation from the proposed extraction area (refer to Figure 2.3). Assessment of the potential for dust generation by sand extraction in the vicinity of the site but outside of the proposed extraction area would comprise additional assessment.




2 SITE DESCRIPTION

2.1 Site Location and Setting The following information was derived from a site visit undertaken by James Magor of ENVIRON on 16th March 2009. During the site visit, discussions were held with Roger Surrage and Geoff White of Outwoods Environmental Consultants.

The proposed development site is located in Staffordshire, approximately 2.75km to the west of Gnosall village and approximately 4.75km to the west of Newport town centre at National Grid Reference 379300, 320300 (refer to Figure 2.1).

According to Natural England, the Aqualate Mere Site of Special Scientific Interest (SSSI) occupies an area of 241 hectares. The Mere is designated a Ramsar site and part of the SSSI is also designated a National Nature Reserve. The eastern boundary of the SSSI is located c.360m to the west of the western site boundary of the proposed extraction area. The Humesford Brook, which flows into Aqualate Mere, is located c.250m to the north-west of the proposed extraction area.

The surrounding land to the north, south and east comprises open land of agricultural appearance. The nearest residential properties to the site are located on Radmore Lane c.1km to the east. In addition, farm buildings are located 330m to the east and 500m to the north-west.

Figure 2.1: Site Location




2.2 Existing Site Description The proposed extraction area (‘the site’) occupies an area of c.30,250 m2 (c.3 hectares) and currently comprises undeveloped Greenfield land with evidence of former sand extraction works (refer to Figure 2.2). According to Outwoods Environmental Consultants (OEC), the site and surrounding land is owned by Aqualate Estate and sand extraction was reportedly first undertaken at the site in the 1920s. Planning permission for sand extraction was reportedly first granted in the 1950s and the area was last worked in the 1990s. ENVIRON is not aware of any previous issues relating to dust.

Topographically, the site is highly uneven. Historic sand extraction works took place towards the centre of the site, where site levels vary between 92.4m above ordnance datum (AOD) and 75.4m AOD over a distance of 65m. The central and western section of the site comprises a vegetated ‘mound’ which screens the central extraction area from land off-site to the west. A tributary to the Humesford Brook flows from east to west approximately 10m to the north of the proposed extraction area and is situated between 2m and 4m below adjacent site levels. Four ponds are located in the northern section of the leased area (refer to Figure 2.2).

Vehicular access to the site was formerly provided by an unsurfaced track which extends off site to the east and connected the former sand extraction works to an unnamed road located c.200m to the east of the site. The track is currently overgrown and access to the site is on foot. In addition, Guild Lane (a single carriageway road) is located c.350m to the west of the west of the site and additional pedestrian access to the site is provided via a footpath from Guild Lane.

Figure 2.2: Existing Site Layout




2.3 The Proposed Development According to OEC, planning permission for the proposed sand extraction works was reportedly obtained by the Aqualate Estate, the land owner, in 2002. The application was considered under the County Council’s Review of Old Mineral Permissions (ROMP). It is understood the Traxx (Aggregates) Limited (the Client) is proposing to lease the site and surrounding land from Aqualate Estate and undertake sand extraction works under the 2002 planning permission.

The proposed sand extraction works will be accessed via Guild Lane and an access road will be constructed across the land leased by the client. The road will be constructed of hardcore and asphalt road planings and vehicular access to the site will be from the north-west. A small site office and weighbridge will be constructed adjacent to the site entrance. The weighbridge will be mounted on concrete pads with concrete approach ramps and will occupy an area of c.45m2. The site office will be of a standard mobile type (‘Portakabin’) painted in dark olive green. Plant and heavy machinery used on-site will comprise a face shovel and dry screen.

It is proposed that heavy goods vehicles (HGVs) accessing the site will be filled directly from the sand face and there will be minimal stockpiling of extracted materials. The maximum daily output from the site will not exceed 300 tonnes per day and the site will be operational Monday to Friday and Saturday mornings. It is anticipated that the site generate a maximum of four HGV movements (two ‘each way’ movements) per hour.

As per the planning permission, sand will be extracted to a maximum depth of 74m AOD and the works will be undertaken in three phases, as per Figure 2.3.

Figure 2.3: Proposed Working Phases




3 LOCAL AIR QUALITY AND ASSESSMENT CRITERIA

3.1 Local Air Quality Management The Environment Act 19951 provides for the development of a national Air Quality Strategy2

(AQS), containing a framework for the continual improvement of ambient air quality. Part IV of the Environment Act 1995 requires local authorities to review and assess current and future air quality in their areas against the objectives included in the AQS, as prescribed in the regulations for the purposes of Local Air Quality Management (LAQM). The initial assessments were carried out in a number of increasingly detailed stages and, in many cases, involved predictive work using air dispersion modelling techniques.

If air quality was predicted to not meet the air quality objectives (AQOs) within certain areas by the relevant date, the local authority was required to designate those areas as ‘Air Quality Management Areas’ (AQMA). Within 12 months of designation, the Local Authority was required to draw up an action plan for each AQMA detailing measures and target dates in order to improve air quality and meet the objectives.

In 2008 Stafford Borough Council (SBC) completed an Air Quality Progress Report3, which confirmed that the AQOs for all pollutants were likely to be met throughout the Borough and there is no requirement to undertake a detailed assessment. Previous Progress Reports and Updating and Screening Assessments, which date back to 2000, stated that there have been no significant breaches of the AQOs in Stafford Borough and it has not proven necessary to designate any air quality management areas (AQMAs) nor to implement an Action Plan.

3.2 Dust Deposition and PM10 According to the Minerals Policy Statement4, dust is a generic term used to describe particulate matter in the size range 1 – 75 μm in diameter. However, standards or limits for deposited dust have not been set within UK regulations and there are no formal guidelines on what level of deposition constitutes a nuisance.

Dust particles that are less than or equal to (≤) 10 μm in diameter are commonly referred to as ‘fine particulates’ or PM10. The objectives for fine particulates for the protection of human health adopted in the UK are defined in the latest Air Quality Strategy for England, Scotland, Wales and Northern Ireland, published on 17th July 2007. They are based on the limit values required by EU Daughter Directives on Air Quality and have been transposed into UK

1 HMSO (1995) The Environment Act 1995, Part IV Air Quality

2 The Air Quality Strategy for England, Scotland, Wales and Northern Ireland (January 2000)

3 Stafford Borough Council (2008) Air Quality Progress Report

4 Office of the Deputy Prime Minister (2005) Minerals Policy Statement 2: Controlling and Mitigating the Environment Effects of Minerals Extraction, Annex 1 – Dust




law through the Air Quality Standards Regulations 2007 which came into force on 15th February 2007. The relevant objectives are provided below in Table 3.1.

Table 3.1: Air Quality Objective Particles (PM10)

Averaging period Concentration To be achieved by

Short term 24 hour mean 50 µg m-3, not to be exceeded more than 35 times a year

31 December 2004

Long term annual mean 40 µg m-3 31 December 2004

3.3 Expected Air Quality at the Development Site The air quality at any given locality will be impacted both by local sources, i.e. nearby roads, industrial activities etc. and background concentrations, with the significance of the two components varying depending on the pollutant. Nitrogen dioxide concentrations are most influenced by local sources and can decrease rapidly away from a source. Thus, on large sites adjacent to busy roads, some variation in concentrations would be expected across a site. PM10 concentrations, on the other hand, are more influenced by background concentrations, which are made up of coarse and secondary particles formed in the atmosphere. As a result, local sources have less influence on concentrations and less variability is seen on a local scale.

According to the progress report, SBC does not routinely monitor background concentrations of PM10 in the Borough as a breach of the AQOs is considered unlikely. Therefore, additional information on estimated background pollutant concentrations has been obtained from the Defra background maps provided on the National Air Quality Archive website (www.airquality.co.uk). Estimated air pollution concentrations for PM10 have been extracted from the 2004 background pollution maps for the UK. Concentrations have been taken from the grid squares in the vicinity of the development site, providing average concentrations for the area. The maps provide concentrations for 2005, which have been adjusted using the background adjustment calculator also available on the website. The resulting concentrations are provided below in Table 3.2.

The data indicates background concentrations in the region of the development site are comfortably below the annual mean PM10 objective and are predicted to remain below the objective in 2009 and 2010.

Table 3.2: Annual Mean Background PM10 Concentrations for SBC Year Annual mean PM10 concentrations (µgm-3)

2008 13.80

2009 13.64

2010 13.49




Given that background concentrations of all pollutants are expected to meet the air quality objectives throughout the Borough, and taking into account concentration on the Defra background maps, it is anticipated that background concentrations of PM10 at the development site will be significantly below the Air Quality Objective of 40 μg m-3.




4 IDENTIFICATION OF POTENTIAL IMPACTS

4.1 Sources of Dust – Construction The subject site comprises a sand pit / quarry created by previous sand and gravel extraction activities. The site has reportedly not been worked since the 1990s and the site surfacing comprises a mixture of vegetated (grass) surfacing and exposed sand faces. The site is considered to be capable of accommodating the proposed sand extraction works in its current condition without significant ground preparations. Furthermore, the proposed development will not comprise any demolition activities. Construction activities will be limited to the erection of a weighbridge, an access road and a site office (Portakabin). The site office will not require foundations and will be removed at the end of the proposed extraction.

The potential for the generation of dust due to ground preparation and construction activities is considered to be negligible.

4.2 Sources of Dust – Operational Activities During the operation of the sand extraction works, emissions of dust may potentially arise from the following activities:

• heavy goods vehicles (HGVs) accessing the site (through the movement of the HGVs over unpaved or soiled surfaces);

• sand blown from HGVs leaving the site;

• sand blown from the working face;

• loading the extracted sand into HGVs;

• handling of overburden;

• screening of extracted sand; and

• dust blown from storage of sand.

4.3 Dust Deposition Greenfield Associates (GA) was commissioned to produce a geological report on the mineral reserves available at the Weavers Hill sand pit and the report, dated 19th November 2008 (ref: JPS/AQQ/102), was reviewed by ENVIRON. During the assessment undertaken by GA, six sand samples were reportedly obtained from the exposed faced within the proposed extraction area and laboratory tested in accordance with the BS 993-1:1997 to determine the particle size distribution of the material present.

The testing reportedly confirmed that the majority of the sand (c.83% – 97%) lies between the 0.5mm to 0.125mm sieve size and that the sand had a low fines content with ≤5% passing the 0.063mm (63μm) sieve. In addition, eleven boreholes were installed at the site by GA which revealed only a thin cover of topsoil and subsoil overburden, generally considered to be no more than 0.3m in thickness.



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Based on the study by GA, dust potentially arising from the identified operational activities is coarse and of a similar nature to construction dust. Deposition of coarse dust can lead to soiling of property including windows, cars, external paintwork and laundry. Disruption due to coarse dust is a localised phenomenon and in general, only people living or working within 100 metres of ‘construction activities’ or dust sources are likely to be seriously impacted by nuisance dust5.

According to the Minerals Policy Statement, the ability of dust particles to remain suspended in the air depends on their shape, size and density. Large dust particles (>30 µm) will largely deposit within 100 m of sources. Intermediate dust particles, between 10-30 µm, generally deposit within 200 to 500 m of sources, while smaller particles (<10 µm) may travel 1 km from sources. According to the GA study, the majority of the sand at Weavers Hill sand pit is coarse in nature with ≥95% of particles larger than 63 µm. Therefore, it is anticipated that the majority of the dust will be deposited within 100 m of the source.

Only a small proportion (≤5%) of the dust generated will have a particle size smaller than 63 µm and it is anticipated that a very small proportion of the dust will be of a fine nature (e.g. PM10), which can enter the human respiratory system and result in adverse health effects. High emissions of fine dust typically arise from specialist activities, such as aggregate crushing, however no operations of this nature will be undertaken at the site.

4.4 Receptors Like other air borne pollutants, dust is dispersed by the wind. However, because of its coarse nature, the dust tends to be deposited relatively close to its point of origin and thus impacts are limited to a relatively small area around a development site (within 100m). In built up areas, neighbouring properties can act as screens, further limiting the movement of dust particles. More widespread movement can occur by the re-suspension of dust particles, by the movement of heavy goods vehicles or during exceptionally dry and windy conditions.

The immediate surroundings including the buildings, roads and open areas, together with the people who access them, will be those most at risk of being exposed to dust effects. Receptors downwind of the predominant wind direction from a development site will be at greater risk of impacts than those upwind. The Windrose from the Birmingham meteorological station is provided in Figure 4.1 (below) and shows that the predominant wind direction in the West Midlands is from the west. Receptors to the east of the site will therefore be most at risk from dust impacts.

5 Baughan C J (1980) Nuisance from Road Construction: a study at the A31 Poulner Lane Diversion, Ringwood.

TRRL Supplementary Report 562, from DTLR (1994) Design Manual for Roads and Bridges



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Figure 4.1: Windrose from Birmingham Meteorological Station (2007)

A review of land uses surrounding the site has identified the following:

Residential properties: The nearest residential properties are located on Radmore Lane c.1km to the east of the site. In addition, farm buildings are located 330m to the east, 500m to the north-west and 680m to the south-east;

Community/Educational facilities: No community or educational facilities were identified within 500m of the site. The nearest facility to the site is a school located in Newport approximately 5km to the south-west;

Commercial/Retail/Office Units: No commercial/retail/office units were identified within 1km of the site. The nearest commercial units are located in Gnosall Heath, located c.2.5km to the east; and



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Open Countryside and SSSIs: The site is bordered in all directions by open countryside. The eastern boundary of the Aqualate Mere SSSI is located c.360m to the west of the western site boundary of the proposed extraction area.

As discussed previously, ≥95% of particles are larger than 63 µm and would therefore be deposited within 100m of source. Research into the impacts of coarse dust has revealed that at least half the people living within 50m of the site boundary tend to be seriously bothered by dust generated during construction activities (or similar), but beyond 100m the number of people seriously bothered drops to less than 20 percent.

Due to the westerly prevailing wind, sites to the east are likely to be at greatest risk of dust impacts. The nearest residential properties to the site are located c.1km to the east with farm buildings located 330m and 690m to the east. According to the Minerals Policy Statement, Farms are considered to be of ‘low sensitivity’ with respect to nuisance dust.

Whilst the risk is lessened given the distance and relative ‘up wind’ location, Aqualate Mere SSSI located 360m to the west of the site, is the sensitive receptor likely to be most at risk of dust impacts due to the close proximity to the development site.



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5 CONTROL OF DUST Because of the nature of the dust likely to be generated by sand extraction activities, the control of dust emissions relies upon management provisions and mitigation techniques. However, where dust emission controls have been used effectively, large-scale operations have been successfully undertaken without nuisance to nearby receptors. The prudent use of water application, good site planning and management will ensure effective dust control.

Measures to prevent dust emissions impacting Aqualate Mere SSSI (the nearest sensitive receptor) will include the following practices:

• a water bowser will be in operation to dampen stockpiles and loading of sand. Water will be obtained from the four ponds in the northern section of the leased area (refer to Figure 2.2);

• stockpiles will be sprayed prior to removal or processing

• all vehicles leaving the site will be required to use the axle/wheel shaker (rattle bars) to remove debris;

• the new access road will be constructed of hardcore and asphalt road planings to prevent significant dust generation;

• vehicles carrying sand off-site to be sheeted; and

• no fires will be allowed on site.

In addition to the above mitigation measures, sand extraction works will be undertaken in three phases, as per Figure 2.3. This will ensure that the section of the proposed extraction area in closest proximity to the SSSI will be extracted third (last) and will therefore provide a topographical barrier during extraction of Phases 1 and 2. Furthermore the sand extraction ‘working face’ will be directed towards the east (i.e. in the opposite direction of the prevailing wind) to minimise wind action.

ENVIRON understands restoration of the proposed extraction area will comprise the development of a wetlands and formerly worked sand faces will not be exposed in order to minimise the risk of future wind blown dust.

The effectiveness of dust control will be reviewed at regular progress meetings and the name, address and telephone number of the contractor and an environmental manager (responsible for environmental management) will be clearly displayed at the main entrance to the site. Any complaints will be recorded, immediately investigated and acted upon by the environmental manager and reported to SCC. If necessary, the Client will implement a monitoring scheme to further assess the effectiveness of dust control measures.



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6 CONCLUSION ENVIRON understands that sand extraction was first undertaken at the site in the 1920s, planning permission for sand extraction was reportedly granted in the 1950s and the area was last worked in the 1990s. Traxx (Aggregates) Limited (the Client) is proposing to recommence sand extraction activities at the site and requested an assessment regarding the potential effects of the proposed sand extraction works on local air quality, in particular the potential effects of dust on the nearby Aqualate Mere Site of Special Scientific Interest (SSSI).

The proposed sand extraction works will be accessed via Guild Lane and an access road will be constructed across the land leased by the client. The road will be constructed of hardcore and asphalt road planings and vehicular access to the site will be from the north-west. A small site office and weighbridge will be constructed adjacent to the site entrance. Plant and heavy machinery used on-site will comprise a face shovel and dry screen. Sand will be extracted to a maximum depth of 74m AOD and the works will be undertaken in three phases.

The nearest residential properties are located c.1km to the east, however, the Aqualate Mere SSSI is located approximately 360m to the west of the site and is therefore the nearest sensitive receptor to the site.

According to Minerals Policy Statement 2, the ability of dust particles to remain suspended in the air depends on their shape, size and density. Large dust particles (>30 µm) will largely deposit within 100 m of sources. Intermediate dust particles, between 10-30 µm, generally deposit within 200 to 500 m of sources, while smaller particles (<10 µm) may travel 1 km from sources. According to a study by Greenfield Associates (GA), the majority of the sand at Weavers Hill sand pit is coarse in nature with ≥95% of particles larger than 63 µm. In addition, there is only a thin cover of topsoil and subsoil overburden. Therefore, it is anticipated that the majority of the dust will be deposited within 100 m of source.

In conclusion, implementation of the proposed dust mitigation measures (detailed in Section 5) will control the dispersion of nuisance dust arising from site operations. Furthermore, the Aqualate Mere SSSI is located c.360m to the west of the site, which is up-gradient of the prevailing wind and particle size analysis has indicated that the majority of dust generated would be deposited within 100m of the site. Therefore, ENVIRON consider that dust emissions arising from the proposed development would be kept to a minimum (based on the proposed mitigation measures) and the proposed sand extraction works would be able to operate without generating nuisance dust.



UK15-14343 Issue: 2 (Draft)

Annex A: Greenfield Associates drawing (ref: Plan WHQ Extraction Design 74m)

Documents

Dust Assessment Weavers Hill Quarry, Aqualate Estate