9.5.3 Operational Phase Generation and Control of Process ...

PROPOSED SOIL TREATMENT FACILITY – MEECE

NOVEMBER 2011 ENVIRONMENTAL REPORT 9-15

9.5.3 Operational Phase

Generation and Control of Process Water from Biopiles

Any liquid discharge from the biopiles will potentially be contaminated. The nature of that contamination will however be determined by the source material which will vary.

As set out in the incorporated mitigation section to avoid the discharge of this process water into the environment the soil treatment pads, on which the biopiles will be sited, will be drained separately to tank. Liquid from these tanks will then be tankered away from the site for treatment and disposal as required.

The amount of process water that will drain from the soil treatment pads is largely governed by the moisture content of the soil material and the amount of rainfall that falls upon it. The biopiles are required to be moist as part of the treatment process and to avoid the generation of dust, however, if the piles are already wet they will normally be covered to minimise the generation of process water. Experience from similar facilities operated elsewhere in the UK indicate that an annual process water volume of around 900 m3 might be expected from a facility of the size proposed. This is the equivalent of around 60 tanker movements each year.

Based on the proposed tank size of 100m3 is considered to be sufficiently large such that overflow from this system is highly unlikely.

Failure of Process Water Storage Tank

As set out in the incorporated mitigation section all tanks, including the process water storage tank will be sited in a bunded and lined areas with holding capacity of at least 110% of the total tank volume. As such even a catastrophic failure of this tank should not result in discharge of pollution to the storm water systems.

A risk would exist where there are no standard procedures stipulating where on site the pumping of the process water from the process water storage tank into a tanker for removal from the site, is permitted. Whilst unlikely it is conceivable that a valve failure during this process could result in the discharge of up to 15,000 litres of contaminated liquid which would then discharge via the storm water system towards Yarnfield Brook and Meece Brook.

The impact of a pollution event of this nature would evidently be dependent upon the types and concentrations of contaminants within the process water; however adverse impacts on the fauna and flora within the receiving water bodies would be likely.

Increase in Sediment within Storm Water Run-off

Any sediment or soil deposited on the roads around the site may get washed by heavy rainfall into the storm water systems and this will then ultimately act to increase sediment loading in the Yarnfield Brook and Meece Brook downstream. Similarly any sediment or soil deposited by site traffic on nearby roads will also be washed into local surface water receptors.

Where this soil is contaminated (i.e. the soil imported for treatment) impacts relating to chemical quality, as well as levels of suspended solids may also be significant.



Pollution of Site Runoff by Oils and Hydrocarbons

Routine use / presence of lorries, cars and other vehicles across the site and access routes and associated accidental spills or minor leaks all have the potential to contaminate runoff in the locality with hydrocarbons or other chemicals. This could then be flushed through the system during heavy rainfall or flooding events which could then lead to contamination of receptors downstream.

Whilst such impacts are typically minor they may result in a general degradation in the quality of storm water discharges into Yarnfield Brook and Meece Brook.

Pollution Relating to the Storage of Fuels and Chemicals

The proposed STF will not require storage of large volumes of liquid fuels as the plant is operated by electricity and the treatment process does not use fuel or liquid reagents. Small amounts of fuel and other chemicals may however need to be kept on site, but would be stored in designated areas.

As set out in the incorporated mitigation section and in line with legislation, all tanks will be sited within impervious lined and bunded enclosure designed to hold at least 110% of the volume of the tanks. Any spillages will therefore be contained. If any liquid collects within a sump this would be pumped and collected for off-site disposal. As such any significant impact is highly unlikely.

Pollution of Groundwater by Site Operations

All proposed operational activities will occur on areas of impermeable cover and all storm drainage will be contained and directed to the storm water and process water system previously discussed. Given this the potential for pollution of the soils or groundwater below the site is limited. However, without any standard ongoing maintenance and repairs over the operational lifetime of the development, cracks or general deterioration in the condition of hardstanding or pipes could permit discharge of low levels of contamination into the groundwater within the Mercia Mudstone beneath the site. Once into the groundwater the movement of such contamination would be slow due to the low permeability of the Mercia Mudstone. Groundwater flows locally are believed to be to the south-west towards Meece Brook. This feature is relatively remote, providing opportunity for adsorption and breakdown of contaminants.

Table 9.6 provides a summary of the assessment of potential impacts in the operational phase prior to mitigation. Mitigation measures are then separately discussed and impacts reassessed at a later stage.



Table 9.6 Unmitigated Operational Phase Impacts

Source Pathway Receptor Sensitivity of Receptor

Magnitude of Impact

Significance of Impact

Likelihood of Impact

Risk of Impact

Accretion of sediment on hard standing both

from every day activity and spillage from soil transfers

Mobilisation by rainfall into storm

water systems

Yarnfield Brook downstream Medium High High Likely Major

Meece Brook / River Sow Medium Moderate Moderate Likely Moderate

Vehicle movements from the site

Pilstones Wood Tributary / Yarnfield Brook upstream Low Moderate Minor Likely Moderate /

Minor

Yarnfield Brook downstream Medium Moderate Moderate Likely Moderate

Meece Brook / River Sow Medium Moderate Moderate Likely Moderate

Oils and hydrocarbons from

vehicles

Spillage and runoff into drainage system

Yarnfield Brook downstream Medium Minor Minor Low Likelihood Minor

Meece Brook / River Sow Medium Negligible Insignificant Low Likelihood Negligible

Infiltration into ground via cracked

hardstanding

Groundwater within Mercia Mudstone Low Minor Insignificant Low

Likelihood Negligible

Pilstones Wood Tributary / Yarnfield Brook upstream Low Negligible Insignificant Unlikely Negligible

Yarnfield Brook downstream Medium Negligible Insignificant Unlikely Negligible

Meece Brook / River Sow Medium Negligible Insignificant Unlikely Negligible

Process water generated from

biopiles

Exceeding tank capacity and

discharge via storm water system

Yarnfield Brook downstream Medium High High Unlikely Moderate / Minor

Meece Brook / River Sow Medium Moderate Moderate Unlikely Minor

Failure of process water tank and runoff

to storm water system

Yarnfield Brook downstream Medium Negligible Insignificant Low Likelihood Negligible





Magnitude of Impact



Risk of Impact

Failure of value on tanker and release of

process water to storm water system

Yarnfield Brook downstream Medium High High Unlikely Moderate / Minor

Meece Brook / River Sow Medium Moderate Moderate Unlikely Minor

Infiltration via broken hardstanding or cracked pipes

Groundwater within Mercia Mudstone Low Moderate Minor Likely Moderate /

Minor


Yarnfield Brook downstream Medium Negligible Insignificant Low Likelihood Negligible




9.6 Flood Risk Assessment

9.6.1 Sequential Test

As discussed previously the EA flood map shows that the entire site for the proposed STF is located in flood zone 1 indicating that flooding from major fluvial or tidal sources is not currently likely.

The Sequential Test as set out PPS25, requires decision makers to direct development to the lowest risk reasonably available site. In practice this typically means that where development is proposed in higher risk zones (i.e. 2 or 3) it is necessary to demonstrate that there are no reasonably available alternative options that avoid development in this area.

Given that the proposed development is situated wholly within flood zone 1 it is considered to pass the Sequential Test and no further consideration of alternative sites is required within this flood risk assessment.

9.6.2 Sensitivity of Receptors

Within Table D2 of PPS25 waste management facilities (except landfill and hazardous waste facilities) are defined as a ‘less vulnerable development’ type. The STF will fall into this classification and is therefore considered to be moderately sensitive to flooding.

Development in general has the potential to impact the flood risk posed to off-site receptors. All off-site development is considered to have a high sensitivity to any increase in flood risk and, therefore, it is important that any adverse off-site impacts on flood severity or frequency are avoided.

Potential Flood Risks

Within PPS25 it is recommended that the following sources of flooding are considered;

Fluvial: The site is located in flood zone 1 and is remote from all surface watercourses. The closest surface channels are the drains within Piltstone wood that are separated from the site by higher ground;

Tidal: This site is remote from the sea and there is therefore no potential for tidal flooding locally;

Drainage Systems: The drainage systems that flow through and past the site from the north to the south currently have a very limited catchment area consisting of the perimeter road to the north of the landfill and possibly also a small area of agricultural land further north.

Surcharged flows from this system are not considered likely. If the capacity of the drain was exceeded, limited flooding could occur at a location on or immediately to the north of the site. This would however probably only ever occur as a result of a blockage / collapse. If such flooding did occur the severity is unlikely to be severe and flows would simply enter the storm drainage systems proposed for the development;.

Overland Flow: Land to the east of the site within Pilstones Wood is elevated above site levels. Significant flows are however unlikely to be generated from this woodland (i.e. permeable cover) and any limited flows that were generated



would be intercepted by the drainage systems along the road that forms the eastern site boundary.

Following restoration of the landfill, the land to the west of the site will also be elevated above site levels;

Groundwater: Groundwater levels within the Mercia Mudstone have been observed to be several metres below the surface. In addition there are no topographic or geological formations on or adjacent to the site that are likely to give rise to springs; and

Other / Artificial: There are no canals, reservoirs or other artificial features locally that could result in flooding of the site.

Off-site Flood Impacts

Two mechanisms have been identified through which the development proposals could act to exacerbate flood risk off site. These are:

Changes to the drain through the site: A failure to adequately replace or reroute any drains that currently flows through or past the site will result in land drainage problems in the area upstream of the site; and

Changes in storm runoff from the site: The development proposals involve the construction of significant area of impermeable cover including the treatment pad, the surrounding roads and any ancillary infrastructure. This will constitute an increase in impermeable cover on the site which, unless mitigated would result in higher rates of peak storm water runoff. High rates of storm water runoff are likely to exacerbate flood risk along the receiving water bodies downstream.

Table 9.7 provides a summary of the assessment of flood risk prior to mitigation. Mitigation measures are then separately discussed and risk reassessed at a later stage.



Table 9.7 Flood risks prior to mitigation

Flood Source Pathway / Flood Mechanism Receptor Sensitivity Magnitude

of hazard Significance of flooding

Probability of impact Flood Risk

Fluvial None - - - - - - None

Tidal None - - - - - - None

Drainage Systems

North – South drains

Surcharge and flow onto the site STF Medium Minor Minor Unlikely Negligible

Removal of pipes through development

Land up gradient Low Moderate Minor High

Likelihood Moderate

Overland flow

Pilstones Wood Rainfall exceeding infiltration capacity STF Medium Negligible Insignificant Low


Impermeable surface

constructed on site

Increased rates of peak runoff Downstream High Moderate Major High

Likelihood Major

Other Artificial None - - - - - - None



9.7 Mitigation

9.7.1 Construction Phase

The mitigation measures, as set out below, will help to manage any identified negative impacts deemed to be significant during the construction phase.

Where possible, works that have the potential to adversely impact water features, such as extensive earth works, should be avoided. Alternatively such works should be sensibly managed, in accordance with adverse ground and/or weather conditions occurring such as heavy rainfall or waterlogged soils.

Mobilisation of Sediments

Where possible, elements of the proposed storm water drainage system for the site that will assist with pollution control, such as the oil interceptor and attenuation pond, will be constructed at an early stage. Flows from the construction area will then be encouraged to discharge via this system.

In addition to this, a range of other measures for managing silt within the construction areas, as detailed within PPG5, will be implemented. This will include:

Use of sediment traps and installing settlement ponds or tanks where practical;

Directing runoff into designated vegetated ground to reduce silt and suspended solids before discharge off site;

Provision of track or road side drainage channels with small dams to assist with silt retention;

Storage of bulk materials such as aggregate, topsoil and excavated arisings in designated areas away (>20m) from entrance points into the surface water drainage systems;

Minimising the presence of uncovered stockpiles through efficient management of construction activities or the use of tarpaulin covers;

Use of silt fences or other suitable barriers around any uncovered stockpiles to protect them from runoff and control flows. A silt fence comprises a geotextile filter fabric, straw bales, or a combination of both and if installed in the path of runoff can filter out heavy sediments; and

Wheel washing to prevent soils being spread onto roads outside of the construction area.

Contamination from Oils and Chemicals

The storage of polluting materials will be kept to a minimum and, where less hazardous or inert materials are available, these will be specified. For example, where it is considered reasonable to do so, construction materials containing sulphides or cement which could potentially alter the pH of runoff will be avoided and the use of biodegradable hydraulic oils will be considered for construction plant. In addition, absorbent mats/pads, absorbent granules and sand will be made available, and site operatives trained in their use, to deal with any spillages. Any spills will be cleaned up as soon as possible with any contaminated sands bagged up and disposed of correctly.

Further measures to be adopted include locating any obvious pollutant sources such as mobile plant, batching plant, materials storage, topsoil storage, and waste



disposal facilities at least 20m away from any obvious entrance points into the storm drainage systems. In addition, the positioning of fuel storage tanks and other potentially polluting materials and maintenance facilities will be on bunded areas of hard standing with dedicated drainage systems. Stored materials on site will be checked regularly for containment integrity (both primary and secondary), quantity stored and security of storage.

Contamination from Cementitous Material

Building of concrete structures, such as hardstanding areas and footings, during the construction phase would be monitored to prevent cementitious material entering storm water systems. Where appropriate, pre-cast work or permanent formwork will be used. This will help reduce the amount of in-situ concreting required.

Ready mix suppliers will be used instead of on-site batching and wherever possible concrete wagons will be directed to return to their depots to wash out. If this is ultimately not possible washing out would occur in designated and contained areas and all washout water would be neutralised prior to discharge into the local storm water network.

Throughout the construction phase good working practices will be adopted and measures to protect the water environment will be incorporated in accordance with those set out within EA PPG notes as listed in Section 9.2.1.

9.7.2 Operation

Pollution from Soils and Sediment

All loading and unloading of soils within the facility will be undertaken on the soil pads drained to the process water system. As such any soil dropped during the movement of material will not fall in areas draining to the storm water system.

The operation of the treatment process will be conducted in such a way as to control mud and debris from leaving the treatment area. The precise arrangements will vary depending on the nature of the material being manipulated and the prevailing conditions; however, where required this will involve use of the designated vehicle wash prior to the plant returning to any areas draining to the storm water system.

As a further precaution against sediment and soil migrating off site on vehicles, no plant or machinery involved in the treatment process will leave the facility without having used the vehicle washes, located adjacent to the weighbridge. This will ensure that dragout from treatment pads are negligible and therefore roads will be kept clean.

In addition to this, housekeeping measures relating to cleaning the roads and hardstanding areas on the site will be employed on a periodic basis to avoid the accumulation of silts and sediment over time. Finally if soil does become entrained in storm flows from the site, a degree of settlement will be allowed by the presence of the onsite lagoon to attenuate flows.

9.7.3 Management of Process Water

The storm water lagoon for the site will be fitted with a manually operable valve to allow flows from the site to be shut off in the case of a major pollution incident. Whilst this is unlikely to be required shutting off the valve would, under normal conditions, provide storage for several days worth of flows.



Tankers receiving process water for export from the site will be required to park in a designated location on the sealed treatment pads whilst pumping out occurs. This will ensure that in the unlikely event of the failure of the pumping system, any spilt liquids will be contained on the pads and pumped back into the storage tanks via the treatment pad drainage system.

9.7.4 General Management and Maintenance

Throughout operation of the treatment process, regular preventive inspection and maintenance will be carried out. As determined to be necessary based on observations on the site and prevailing weather conditions, preventive / corrective actions, such as covering exposed biopiles, will be undertaken.

Chemical and oil spill kits are present within the site office or treatment plant container should any spillage of process water be noted.

General environmental monitoring check sheets will also be used daily by site staff, which covers environmental issues such as runoff, contamination, fuel spills, noise etc. Where problems are identified these will be investigated thoroughly and, where appropriate, remedial action undertaken to avoid a repeat incident.

Longer term maintenance issues such as the repair of damaged hard standing or pipes would either be addressed as a report, or picked up in regular maintenance checks of the facility.

9.7.5 Further Flood Risk Mitigation

North - South Drain

The drain that currently runs north to south through the site area will be removed as part of the development process as it runs directly beneath the soil pads and if it remained it would constitute a significant potential pollution pathway. A replacement drain to convey the flows from the area to the north of the site will therefore be constructed along the western site boundary connecting into the same system to the south.

Any other surface drainage routes identified will either be diverted around the site.

Storm Water Drainage Systems

As described in the incorporated mitigation section storm water flows from the roads and hard standing around the site, and tarpaulins covering the biopiles would be directed via a full retention oil separator into an attenuation lagoon located near the site entrance (see Figure 4.1).

Discharge from this lagoon will be restricted to the rate of flow that might be expected from an equivalent greenfield site (4.9 l/s), as calculated using the methodology set out in Institute of Hydrology technical report 124. Calculations undertaken indicate that to achieve and ensure that the annual probability of the system capacity being exceeding is less than 1%, will require the lagoon to have a free drainage volume up to 1037 m3 (see Appendix 9.1)

This assumes that tarpaulins cover the entire area of the soil pad (i.e. this whole area is in effect discharging to the storm water system) and that peak rainfall depths will increase by up to 20% over the life time of the development as a result of climate change.



It should be noted that implementation of this system will in fact reduce peak rates of runoff from the site, as certain areas of the site are covered with hard standing and runoff from these areas will be significant.

9.8 Residual Impacts and Conclusions

The assessment of potential impacts following the consideration of mitigation and management measures is summarised in Table 9.8, 9.9 and 9.10.

These tables show that following the consideration of the proposed mitigation and management measures this assessment concludes that there will be no significant residual impacts to the local hydrological environment.



Table 9.8 Mitigated Construction Phase Impacts


Magnitude of Impact



Risk of Impact

Open soil surfaces and stockpiles of

soil

Mobilisation by rainfall


Meece Brook / River Sow Medium Minor Minor Low Likelihood Minor


Pilstones Wood Tributary / Yarnfield Brook upstream Low Minor Insignificant Low Likelihood Negligible



Mobilisation or leaching of

contaminants from soils

Yarnfield Brook downstream Medium Minor Minor Unlikely Negligible

Meece Brook / River Sow Medium Minor Minor Unlikely Negligible

Oils and hydrocarbons used

by construction / demolition plant

Spillages and leaks followed by runoff

into adjacent drains



Infiltration into ground and subsequent

groundwater flow

Groundwater within Mercia Mudstone Low Minor Insignificant Low Likelihood Negligible




Cementitious material

Spillage or washout of plant and runoff

into drainage system

Yarnfield Brook downstream Medium Moderate Moderate Unlikely Minor





Magnitude of Impact



Risk of Impact

Infiltration into ground and subsequent

groundwater flow

Groundwater within Mercia Mudstone Low Moderate Minor Low Likelihood Minor






Table 9.9 Mitigated Operational Phase Impacts


Magnitude of Impact



Risk of Impact

Accretion of sediment on hard

standing both from every day activity and spillage from

soil transfers

Mobilisation by rainfall into storm

water systems

Yarnfield Brook downstream Medium Minor Minor Low

Likelihood Minor



Pilstones Wood Tributary / Yarnfield Brook upstream Low Minor Insignificant Low



Likelihood Minor


Oils and hydrocarbons from

vehicles

Spillage and runoff into drainage

system


Likelihood Minor


Infiltration into ground via cracked

hardstanding

Groundwater within Mercia Mudstone Low Minor Insignificant Low





Process water generated from

biopiles

Exceeding tank capacity and

discharge via storm water system

Yarnfield Brook downstream Medium Moderate Moderate Unlikely Minor


Failure of process water tank and

Yarnfield Brook downstream Medium Negligible Insignificant Low





Magnitude of Impact



Risk of Impact

runoff to storm water system Meece Brook / River Sow Medium Negligible Insignificant Low


Failure of value on tanker and release of process water to storm water system



Infiltration via broken

hardstanding or cracked pipes

Groundwater within Mercia Mudstone Low Moderate Minor Low

Likelihood Minor


Yarnfield Brook downstream Medium Negligible Insignificant Low





Table 9.10 Flood risks following mitigation

Flood Source Pathway / Flood Mechanism Receptor Sensitivity Magnitude

of hazard Significance of flooding

Probability of impact Flood Risk

Fluvial None - - - - - - None

Tidal None - - - - - - None

Drainage Systems

North – South drain

Surcharge and flow onto the site STF Medium Minor Minor Unlikely Negligible

Removal of pipe through development

Land up gradient Low Negligible Insignificant Unlikely Negligible

Impermeable surface constructed on site

Increased rates of peak runoff Downstream High Negligible Insignificant Unlikely Negligible

Overland flow

Pilstones Wood

Rainfall exceeding infiltration capacity STF Medium Negligible Insignificant Low


Other Artificial

None - - - - - - None



10. ARCHAEOLOGY AND CULTURAL HERITAGE

This chapter deals with the potential impacts of the proposed Soil Treatment Facility (STF) on Archaeology and Cultural Heritage. It has been prepared based on the Desk Based Assessment (DBA) that was produced (see Appendix 10.1).

There are no Scheduled Monuments, Listed Buildings, Registered Parks and Gardens, Registered Battlefields, Conservation Areas or local archaeological features on the site. Only two Listed Buildings and a small number of locally recorded archaeological site and features have been identified within a 1km radius from the proposed STF site boundary (referred to as the ‘Study Area’) (see Figure 1 of Appendix 10.1).

Limited ground investigation works 1 were undertaken in 1998 on site, which included three boreholes excavated on or close to the proposed STF. This identified up to 2.2 m of Made Ground. Given the limited scope of intrusive investigation, it is not currently possible to determine the levels of ground disturbance across the STF site when it formed part of the Royal Ordnance explosives filling factory and, subsequently, an Army Training Area. It is acknowledged, however, that the site would have been subject to some degree of disturbance due to its historical use. Therefore the potential for archaeological deposits below ground is predicted to be low. Due to the low potential for below ground remains, no further archaeological investigation is required unless excavation work extending below made ground is proposed.

There are two derelict military bunkers on the site which are in poor condition. It is not considered that these structures are in a suitable condition to warrant re-use and incorporation into the proposals or recording through an historic building survey before demolition.

Due to the scale of the development, and existing screening around the site (woodland and existing buildings), the site is only partially visible from the Coldmeece to Swynnerton road at the point where it passes the site. Therefore, it is predicted that the development will only have a limited impact on the setting of a small area of Swynnerton Hall Park (which is a historic park which extends southwards from the village of Swynnerton) (see Figure 1 (Appendix 10.1, Ref. ARC1) see Section 10.4.4 for further detail) located to the east of the road.

10.1 Introduction

10.1.1 Overview of Potential Impacts on Archaeology and Cultural Heritage

There are two potential impacts associated with the proposed redevelopment of the site on archaeology and cultural heritage assets. These are direct and indirect impacts as set out below:

Direct Impacts are where there is a physical effect (removal, destruction or damage) on the archaeological/historical site, as a result of development. This effect is often adverse and irreversible and occurs during site preparation and initial development stages (such as ground-breaking, excavation and laying of foundations).

1 Error! Reference source not found., Error! Reference source not found., Aspinwall and Company , 1999



Indirect Impacts are impacts on the setting of an archaeological/historical site where a new development will reduce the views to and from the feature. The development may also change the original archaeological context of the feature and therefore interrupt views of the wider historic landscape. Such effects may occur during both the construction and operational phases of a development.

10.1.2 Scope and Consultation

This chapter provides an assessment of the impacts of the proposals on the archaeological sites and cultural heritage assets located within a 1km radius Study Area, see Figure 1 (Appendix 10.1). An indication of mitigation measures to safeguard any archaeology and cultural heritage sites identified within the Study Area has also been provided.

During the production of this assessment, the Principal Archaeologist at Staffordshire County Council (SCC) and the Inspector of Ancient Monuments at English Heritage (West Midlands Office) (EH) were consulted.

The Principal Archaeologist at Staffordshire County Council provided information on Swynnerton Hall Park stating that “I do not foresee any direct physical impacts to heritage assets although the scheme may impact upon the setting of Swynnerton Park (PRN 20744) which lies immediately to the north and west of the site. Swynnerton Park was designed and laid out by Capability Brown during the mid 18th century although the park layout was substantially remodelled in the early 19th century. Owing in part to these later changes, the park is not recorded on the English Heritage Register of Parks and Gardens of Special Historic Interest, although a comparison of the current plan form and that displayed on the 1st Edition Ordnance Survey mapping for the area indicates that its historic plan form and woodland planting have changed little. Taking this into account it is considered that while formal archaeological mitigation would not be appropriate the design of the scheme should bear in mind the historic parkland. I would advise that you maintain, and potentially look to enhance (where appropriate), screening with tree planting along its road frontage”. These requirements have been fulfilled in this assessment.

The Inspector of Ancient Monuments at English Heritage (West Midlands Office) did not provide a response before the submission of this Environmental Report.

Stafford Borough Council planning department was also contacted to obtain information on Listed Buildings and Conservation Areas within the Study Area.

10.1.3 Incorporated Mitigation

In order to reduce the impact on the setting of the southern part of Swynnerton Hall Park, it is proposed that the majority of the existing vegetation will be retained, around the STF, and that additional planting will take place which will increase the screening of the proposed STF from this historic parkland. Further information on the mitigation measures are provided below in Section 10.6.

10.2 Legislation, Planning Policy and Other Guidance

10.2.1 National Legislation

There are a number of legislative documents which protect archaeological resources at a national level as follows:



The Ancient Monuments and Archaeological Areas Act 1979 (as amended) provides legislation so that archaeological sites of national importance are statutorily protected as Scheduled Monuments (SMs). In this case, this legislation is not applicable as the nearest SM is located approximately 1.3 km to the north-west of the site.

The Planning (Listed Buildings & Conservation Areas) Act 1990 (as amended) ensures the protection of Listed Buildings (which are of special or historic interest) and Areas of Conservation (areas of special architectural or historic interest) which have been designated. In this case, this legislation is applicable, as there are Listed Buildings within the Study Area.

10.2.2 Planning Policy

National

Planning Policy Statement 5: Planning for the Historic Environment (PPS5) was published in March 2010. It sets out policies on the conservation of the historic environment in relation to climate change and development, and explains the importance of the preservation of the historic environment and its assets. It also sets out the Government’s objectives for planning for the historic environment.

A practice guide, PPS5 Planning for the Historic Environment: Historic Environment Planning Practice Guide has also been produced (March 2010) to support the policies outlined in PPS5 with explanations and guidance. The purpose of the guide is to assist all parties involved in the planning process to interpret the policies laid out in PPS5 and to assist in their implementation. Therefore this document should be read in conjunction with PPS5.

The above planning policy and guidance is applicable in this case, as there may be below ground archaeological remains on the site and Swynnerton Hall Park is located in close proximity.

Regional

In relation to regional policy the West Midlands Regional Spatial Strategy (WMRSS) was first published in June 2004 (Chapter 5 Air Quality and Odour provides an explanation of the current status for the WMRSS). This includes two policies (QE1: Conserving and Enhancing the Environment and Policy QE5: Protection and enhancement of the Historic Environment) which are relevant to this study due to the presence of Swynnerton Hall Park. Further information on these policies is provided in Appendix 10.1.



Local

The Site lies within the Staffordshire Borough Council area. Therefore there are two planning documents of relevance to this assessment. These are:

The Stafford Borough Local Plan (SBLP) 2001 and the Local Plan 2001 Saved Policies - Post September 2007; and

Staffordshire and Stoke-On-Trent Structure Plan 1996-2011.

The above documents include various local policies which seek to preserve the historic environment associated with the area and the potential for below ground remains. Full details of all relevant local and regional policy are provided in Appendix 10.1 and have been used to inform this assessment.

10.3 Methodology

10.3.1 Desk Study

A DBA was undertaken and this has been used to inform this assessment and is provided in Appendix 10.1.

10.3.2 Assessment Criteria

Magnitude & Significance Criteria

There is no national standard guidance for the determination of an impact on archaeological or cultural heritage resources. Therefore the magnitude and significance of impacts on the artefacts and designations, identified within the Study Area, have been assessed subjectively using professional judgement. For example, where there is no impact due to the distance of the feature from the proposed development, ‘No Impact’ is indicated. Conversely, if a feature which is considered to be ‘Very Important’ would be destroyed or significantly damaged, a ‘Large Adverse Impact’ would apply. Less substantial damage to features of lesser importance would result in impacts of ‘Slight’ to ‘Moderate’ impact significance, depending on the specific circumstances.

In order to assess the significance of any impact it is necessary to first establish the importance of the feature and its condition. The importance of a feature has been classified in accordance with Table 10.1, whilst Table 10.2 explains how the condition of a site/feature (if known) has been determined.



Table 10.1 Determining the Importance of an Archaeological Site/Monument

Level of Importance

Description

Very Important Monuments and buildings which are of international status (e.g. World Heritage Sites)

Important Monuments which are scheduled (Scheduled Monuments) and those unscheduled monuments of schedulable quality Undesignated archaeological sites of outstanding interest (national importance)

Moderate Importance

Archaeological features and sites (including regionally and local authority designated sites) Undesignated archaeological sites which justify designation (regional or local importance)

Minor Importance

Archaeological remains which are in poor condition or are found out of context Undesignated sites and historic landscapes whose importance is limited by poor preservation/survival (local importance)

Source: Based on Table 5.1 of the Design Manual for Roads and Bridges (DMRB) Volume 11 (2004)

Table 10.2 Determining the Condition of an Archaeological Site/Monument

Condition Description Excellent All or majority of the monument still extant

Good Some evidence still extant

Poor Very little evidence still extant

Unknown It is not recorded

Source: SKM Enviros

To give an example of how the sensitivity (see Table 10.3 below) of a monument has been assessed, a ‘Highly Sensitive’ feature could be an ‘Important’ monument of national status (e.g. a SM that is in excellent condition and is currently established as a visitor attraction (e.g. a Hillfort)). An example of a monument which is of ‘Low Sensitivity’ could be of Moderate or Low Importance (i.e. a monument of local importance), which is either a single isolated building or a feature which is in poor condition and is not visited by the public. If the condition of the archaeological site/monument is unknown then it is not possible to establish the sensitivity of the site/monument.

Table 10.3 Determining the Sensitivity of an Archaeological Site/Monument

Level of Importance

Condition of Importance Excellent Good Poor Unknown

Very Important High Sensitivity High Sensitivity Medium Sensitivity Cannot be Determined

Important High Sensitivity High Sensitivity Medium Sensitivity Cannot be Determined

Moderate Importance

Medium Sensitivity Medium Sensitivity Low Sensitivity Cannot be Determined

Minor Importance

Medium Sensitivity Low Sensitivity Low Sensitivity Cannot be Determined

Source: SKM Enviros



The magnitude of any impacts is determined by the degree of damage to the feature or the prominence of the proposals within the setting of the feature as set out in Tables 10.4 and 10.5 below.

Table 10.4 Determining the Degree of Damage to the Asset

Magnitude of Indirect/Direct

Impact

Description

High Complete destruction of the feature (direct impact)

Medium Considerable damage to feature (direct impact) or complete change in setting (indirect impact)

Low Partial damage (direct impact) or considerable change in setting (indirect impact)

Negligible Minor impact on setting (indirect impact)

None No damage (direct impact) /no impact on setting (indirect impact)

Source: SKM Enviros

Table 10.5 Determining the Prominence of the Proposals

Magnitude of Indirect Impact

Description

High The whole development site is completely visible

Medium Certain sections/areas of the development are visible as natural screening (e.g. wooded areas, tree belts or hedges) around the site interrupts views

Low The majority of the development is screened by existing natural barriers (e.g. wooded areas, tree belts or hedges) or other development which has already taken place. Furthermore, the setting of the archaeological feature itself has already been altered by development

Negligible The majority or all of the development is screened by existing natural barriers (wooded areas, tree belts or hedges) or other development has already taken place and/or the setting of the archaeological features has been completely altered by previous development

None The development is not visible at all

Source: SKM Enviros

Even though the levels of indirect impact range from High to Negligible/None, it must be noted that these impacts will not be as damaging as direct impacts which would involve actual physical damage or destruction. Magnitude has also been assessed by considering the distance between the proposals and the feature and the visibility of the proposals in question. Combining magnitude and sensitivity, the significance of the impacts on the archaeology and cultural heritage assets which have been identified within the surrounding area, have been established using the tables above as combined in the matrix below, Table 10.6 below.



Table 10.6 Archaeological Assessment Matrix Table

Magnitude of Impact

Level of Sensitivity High Medium Low None

High Large Significance Large Significance Moderate Significance

Slight Significance

Medium Moderate Significance

Moderate Significance

Slight Significance Neutral Significance

Low Slight Significance Slight Significance Neutral Significance Neutral Significance

Negligible Neutral Significance

Neutral Significance

Neutral Significance None

None None None None None

Source: Based on Tables 6.1 and 7.2 in Design Manual for Roads and Bridges (DMRB) Volume 11 (2004)

The nature of the impact has also been considered in terms of whether it would be a beneficial or adverse (Tables 10.7 and 10.8 below).

Table 10.7 Determining the Significance of Impact (Beneficial)

Impact Significance Description

Large Provide potential, through removal, relocation or substantial mitigation of very damaging or discordant existing impacts (indirect) 1* on the heritage, for very significant or extensive enhancement of their setting. Make a major contribution to government policies for the enhancement of the heritage. Remove or successfully mitigate existing visual intrusion, such that the integrity, understanding and sense of place of a highly valued area, a group of sites or features of national or regional significance is re-established.

Moderate Provide potential, through removal, relocation or mitigation of damaging or discordant existing impacts on the heritage, for significant restoration of characteristic features or their setting. Contribute to regional or local policies for the enhancement of the heritage. Enhance existing historic landscape/townscape character through beneficial landscaping/mitigation and good design.

Slight Impacts which are not in conflict with national, regional or local policies for the protection of the heritage. Restore or enhance the sense of place of the heritage resource through good design and mitigation. Remove or mitigate visual intrusion or other (indirect)1* impacts into the context of locally or regionally significant heritage features, such that appreciation and understanding of them is improved.

Neutral Not in conflict with, and do not contribute to policies for the protection or enhancement of the heritage. Maintain existing historic character in a landscape/townscape; have no appreciable impact, either positive or negative, on any known or potential heritage assets. Consist of a combination of slight positive and negative impacts, on aspects of heritage that are of minor importance; do not result in severance or loss of integrity, context or understanding within a historic landscape.

None There are no impacts predicted upon the cultural heritage.

Source: Level of Impact and Description information has been extracted from TAG Unit 3.3.9 within the Department for Transport’s Transport Analysis Guidance (WebTAG) 1* Indirect Impact: where there is an impact on the setting of the feature/monument in relation to the development/operation of the site as it will create a change in the surrounding landscape



Table 10.8 Determining the Significance of Impact (Adverse)

Impact Significance

Description

Large Have a high adverse direct impact on very important heritage assets such that their integrity is severely damaged. Have a medium adverse direct impact or compromise the wider setting of multiple very important or important heritage assets, such that the cumulative impact would seriously compromise the integrity of a related group or historic landscape/townscape. Have a high adverse direct impact on important heritage assets, such that their integrity is lost and no adequate mitigation can be specified. Would be highly intrusive and seriously damage the setting of the heritage resource, such that its context is seriously compromised and can no longer be appreciated or understood. Be in serious conflict with government policy for the protection of the heritage, as set out in PPG15 and PPG16. Be strongly at variance with the form, scale and pattern of a historic landscape/townscape.

Moderate Impacts which are out of scale with, or at odds with the scale, pattern or form of the heritage resource. Are intrusive in the setting (context), and adversely affect the appreciation and understanding of the characteristic heritage resource. Are in conflict with local or regional policies for the protection of the heritage. Are damaging to very important heritage assets, resulting in the loss of features such that their integrity is compromised, but not destroyed, and adequate mitigation has been specified. Have a high adverse direct impact on important or moderately important heritage, resulting in loss of such that their integrity is substantially compromised, but adequate mitigation can be specified.

Slight Impacts which are in conflict with local policies for the protection of the local character of the heritage. Have a detrimental impact on the context of regionally or locally significant assets, such that their integrity is compromised and appreciation and understanding of them is diminished. Damage locally significant heritage features for which adequate mitigation can be specified; do not fit well with the form, scale, pattern and character of a historic landscape/townscape/area.

Neutral Not in conflict with, and do not contribute to policies for the protection or enhancement of the heritage. Maintain existing historic character in a landscape/townscape; have no appreciable impact, either positive or negative, on any known or potential heritage assets. Consist of a combination of slight positive and negative impacts, on aspects of heritage that are of minor importance; not result in severance or loss of integrity, context or understanding within a historic landscape.

None There are no impacts predicted upon the cultural heritage.

Source: Level of Impact and Description information has been extracted from TAG Unit 3.3.9 within the Department for Transport’s Transport Analysis Guidance (WebTAG)



10.4 The Baseline Environment and Sensitive Receptors

10.4.1 Geology & Topography

The site comprises relatively flat ground at approximately 115m to 118m Above Ordnance Datum (aOD).

The underlying geology is Mercia Mudstone with occasional Mudstone and Halite-stone deposits. The site is located within the boundary of an existing landfill. Limited ground investigation works were undertaken in 1998 on site, which included three boreholes excavated on or close to the proposed STF. This identified up to 2.2 m of Made Ground. Given limited scope of intrusive investigation, it is not currently possible to determine the levels of ground disturbance across the STF site. Previous development has taken place on site and, therefore, it is expected that some ground disturbance has taken place. Although the extent of this disturbance cannot be established with a high degree of certainty given limited site investigation works.

10.4.2 Historical Background

There is no evidence suggesting that the site and surrounding area was used during the prehistoric and Romano-British periods. Although, this lack of evidence could be due to the fact that only a small number of archaeological investigations have taken place in the area.

In relation to the medieval period, evidence of ridge and furrow field systems has been recorded within the study area from aerial photographs dating to the 1960s. Maps dating to the 1800s demonstrate that the STF site comprised fields, therefore, it is believed that the site was likely to have been used for agricultural purposes during the medieval time prior, and up to the 1800s.

In relation to the site, the same aerial photograph shows that there was a large ‘L-shaped’ building, other smaller buildings, a hard area compound and a track on the area of the site to the east side of Meece Avenue, whilst the site area to the west of Meece Avenue was mainly undeveloped. An aerial photograph taken in 1955, shows that the only change to the site area relates to the construction of another building adjacent to the ‘L-shaped building’. By the 1960s clearance activities had started on the Swynnerton Army Training Area. Furthermore, the large buildings on the eastern area of the site had been cleared and only a few of the smaller buildings remain. During the 1970s and 1980s the northern part of the training area was cleared and, from the 1990s, the site was used as a landfill. The southern part of the training area remains in use by the Ministry of Defence.

Today only two small buildings remain standing on the eastern part of the site, along with the concrete compound. The Historical Landscape Characterisation database records that the characterisation for the training area and part of the site is ‘military’. Further information on the historical development of the area is provided in Appendix 10.1.

10.4.3 Archaeological Sites/Features

Scheduled Monuments

There are no Scheduled Monuments (SMs) within the site boundary or Study Area.



Designations

The site is not located within a Conservation Area. There are no Registered Parks and Gardens or Battlefields on the site or within the Study Area.

Listed Buildings

None of the buildings within the site boundary are listed. There are however, two Listed Buildings recorded within the Study Area. These are:

Meece House which was a Grade II three storey building dating to the 19th century, however this has been delisted and demolished ( Ref LB1); and

A range of Grade II outbuildings adjoining the north-eastern side of Meece House, comprising three blocks dating to the 19th century. These buildings are still extant and are located approximately 1km to the south of the site boundary (Ref. LB2).

Known Archaeological Features on the Site

There are no archaeological features or cultural heritage assets recorded within the STF site boundary. There are two military bunkers of modern date on the site, although these are in poor condition.

Potential Archaeological Features on the Site

As very limited ground investigation works have been undertaken, it is not possible to determine the levels of ground disturbance across the site from the period when it formed part of the Royal Ordnance explosives filling factory and, subsequently, the Army Training Area. Therefore, there is the potential for archaeology deposits deep below ground. However, it is acknowledged that the site would have been subject to some degree of disturbance due to its historical use. As such the potential for archaeology deposits below ground is predicted to be low. This is supported by the correspondence received from the Principal Archaeologist at Staffordshire County Council.

Archaeological Finds within the Study Area

There are a number of archaeological features which have been recorded within the Study Area (see Figure 1 (Appendix 10.1) and are detailed below with further information is provided in Appendix 10.1.

There are no features dating to the prehistoric (450,000 BC to AD 43) or Romano-British (AD 43 to AD 410) periods on the site or within the Study Area. There are three natural sandstone outcrops located approximately 1.5km to the north-west, which were once thought to be barrows (Ref. ARC7).

Medieval Period (AD 410 to AD 1500)

There are three features within the Study Area which date to the Medieval period. These all relate to medieval ridge and furrow field systems which are recorded on aerial photographs. One area of ridge and furrow is located within Swynnerton Park (Ref. ARC4), whilst the other two areas are located immediately to the south-east of Swynnerton Park (Ref. ARC3) and north-east of Coldmeece (Ref. ARC8).



Post-Medieval to Modern (AD 1500 to present)

There are 10 features which date to the post-medieval or modern period these include Swynnerton Hall Park which is a landscaped park dating to the mid 18th century, part of which has been built over (Ref. ARC1), fishponds located within Swynnerton Hall Park (Ref. ARC6), an outfarm situated near Grange Farm (Ref. ARC5), Cold Meece Hall Park (Ref. ARC12), Royal Ordnance explosives filling factory (No. 5) (Ref. ARC2), Three Second World War air raid shelters (Refs. ARC9 to ARC11, Cold Meece Railway Station (Ref. ARC13) and a munitions railway which served the Royal Ordnance explosives filling factory (Ref. ARC14).

Archaeological Investigations within the Study Area There have been no previous archaeological investigations undertaken on the site. Two investigations have been identified in the Study Area. These include:

Staffordshire County Council carried out an archaeological desk-based assessment of the M6 corridor in Staffordshire in 1991 (Ref. INV1). As this covers the surrounding area it is not shown on Figure 1 in Appendix 10.1; and

A photographic survey was undertaken in 2000, approximately 1km to the south by the Potteries Museum Field Archaeology Unit, during the alteration to a building dating to the post-medieval period.

10.5 Impact Assessment

This section discusses the potential impacts (prior to mitigation) of the proposals on the recorded archaeological and cultural heritage resources identified within the Study Area. Both direct/indirect and short-term (during the construction phases) and medium/long term (once the development on site has been completed and is operational) impacts have been considered.

Table 10.8 provides an indication as to level of importance and sensitivity of each feature, the magnitude of impact on these assets and the significance of any impacts.


OCT 2011 ENVIRONMENTAL REPORT 10-12

Table 10.8 Evaluating the Importance, Condition, Sensitivity, Magnitude and Significance of Impacts associated with the Archaeological Features within the Study Area

Site/Feature Details Level of Importance

Level of Condition

Level of Sensitivity

Magnitude of Impact Significance of Impact

LB1 Meece House Minor (as undesignated)

Demolished None None None The building has been demolished and is non-extant.

LB2 Outbuildings (associated with former Meece House)

Moderate Good Medium None None Due to the distance between the Listed Building and the site and the presence of existing screening, the proposals will not be visible, therefore no impact is predicted.

ARC1 Swynnerton Hall Park Moderate Good Medium Negligible Neutral As there is limited visibility of the site from the road immediately adjacent the site, the proposals will have a limited impact on the setting of Swynnerton Hall Park. It should be noted however, that the park is not designated as a Historic Park and Garden and the proposals will only have an impact on the very peripheral southern part of the Park.

ARC2 Royal Ordnance explosives filling factory

Moderate Importance

Poor Low None None The site has undergone redesign and development when the army training area was formed. Furthermore, due to the existing screening, the proposals will not be visible, therefore no impact is predicted.

ARC3 Ridge and furrow Minor Importance

Unknown Cannot be determined

None None Due to the distance between this feature and the site and the presence of existing screening, the proposals will not be visible, therefore no impact is predicted.







Level of Condition



ARC5 Outfarm (part of Grange Farm)

Moderate Importance



ARC6 Fishpond (within Swynnerton Hall Park)

Moderate Importance



ARC7 Natural stone outcrops (within Swynnerton Park)

Minor Importance






ARC9 Double surface air raid shelter

Moderate Importance



ARC10 Double surface air raid shelter

Moderate Importance



ARC11 Surface air raid shelter

Moderate Importance






Level of Condition



ARC12 Cold Meece Hall Park

Moderate Importance



ARC13 Cold Meece railway station

Moderate Importance



ARC14 Cold Meece branch railway

Moderate Importance





10.5.1 Impacts – Construction Phase

During the construction and decommissioning stages of the development, some impacts are predicted, detailed as follows:

As there is limited visibility of the site from Swynnerton Hall Park, there will be a limited impact on the setting of the Park. Furthermore, this impact will only relate to the peripheral southern part of the Park.

10.5.2 Impacts – Operational Phase

It is not considered that there will be additional impacts associated with the proposals during the operational phase of the STF.

10.6 Mitigation

10.6.1 Construction Phase

Due to the condition of the two military bunkers on the site, it is not considered that they warrant re-use and incorporation into the proposals or recording through a historic building survey prior to demolition.

In order to reduce the impact on the setting of Swynnerton Hall Park, it is proposed that the current scrub and wooded areas around the site boundary be retained and additional planting takes place to provide further screening of the construction and operation activities of facility from this feature (see also Chapter 6 Landscape and Visual Impact Assessment).

10.6.2 Operation

As no additional impacts are predicted no further mitigation measures are proposed.

10.7 Residual Impacts and Conclusions

In conclusion, the proposed STF will have a limited indirect impact on the southern part of Swynnerton Hall Park. The implementation of the mitigation measures set out above will assist in reducing these impacts to none.

ARC1

ARC2

ARC3

ARC4

ARC5

ARC6

ARC7

ARC8

ARC9

ARC10

ARC11

ARC12

ARC13

ARC14

LB2

LB1

INV2

CONDITION THAT NONE OF THE INFORMATION SHALL BE DISCLOSED TO ANY THIRD PARTY OR REPRODUCED INTHIS INFORMATION IS CONFIDENTIAL AND THE PROPERTY OF BIFFA WASTE SERVICES LTD. AND IS RELEASED ON

DRAWING No.

DRAWING TITLE

LOCATION

PROJECT

COMPUTER REF.

SCALE(S)DRAWN DATE

DESCRIPTIONDATEREV. DRAWN

WHOLE OR PART WITHOUT THE PRIOR CONSENT IN WRITING OF BIFFA WASTE SERVICES LTD.

AJR9351

October 2011

.

1:15,000AJR

Meece Landfill Site, Swynnerton

Proposed Soil Treatment Facility

Biffa Waste Services Ltd.Portland HouseBickenhill LaneBirminghamTel. 0121 6616710Fax. 0121 7828754

E-mail [email protected]

Application Area

Archaeology Sites and Features

Listed Buildings

Investigations

Monuments, Buildings and Structures

1km Buffer Zone

(Polygons)

NOTE:INV1 covers a wider area and therefore has not beenplotted

Data has been supplied by Staffordshire CountyCouncil Historic Environment Record and the NationalMonuments Record

SKM EnvirosEnviros HouseShrewsbury Business ParkShrewsburyShropshireSY2 6LGTel: +44 (0)1743 284800Fax: +44 (0)1743 245558


Figure 10.1 Archaeological and CulturalHeritage Resources

N

Reproduced from Ordnance Survey digital map data © Crown copyright 2011 All rights reserved.Licence number 0100031673

Biffa Waste Services Ltd.Portland HouseBickenhill LaneBirminghamTel. 0121 6616710Fax. 0121 7828754

E-mail [email protected]

Application Area

1km Buffer Zone

Ancient Woodland

Other Early Woodland

Plantations

Early Irregular Enclosure

Piecemeal Enclosure

Post 1880s Small Replanned Enclosure

Historic Parks & Gardens

Other Parkland

Pre 1880s Settlement

Post 1880s Settlement

Industrial and Extractive

Military

Historic Landscape Character

Post 1880s Reorganised PiecemealEnclosure

NOTE:Data has been supplied by Staffordshire CountyCouncil Historic Environment Record and the NationalMonuments Record

Figure 10.2 Historic Landscape Character



CONDITION THAT NONE OF THE INFORMATION SHALL BE DISCLOSED TO ANY THIRD PARTY OR REPRODUCED INTHIS INFORMATION IS CONFIDENTIAL AND THE PROPERTY OF BIFFA WASTE SERVICES LTD. AND IS RELEASED ON

DRAWING No.

DRAWING TITLE

LOCATION

PROJECT

COMPUTER REF.

SCALE(S)DRAWN DATE

DESCRIPTIONDATEREV. DRAWN

WHOLE OR PART WITHOUT THE PRIOR CONSENT IN WRITING OF BIFFA WASTE SERVICES LTD.

Proposed Soil Treatment Facility

Meece Landfill Site, Swynnerton

AJR 1:15,000

.

October 2011

AJR9351

N

Reproduced from Ordnance Survey digital map data © Crown copyright 2011 All rights reserved.Licence number 0100031673

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