York Potash Project Mine, MTS and MHF Environmental Statement, Part 2 Chapter: 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan

Transcription

1 York Potash Project Mine, MTS and MHF Environmental Statement, Part 2 Chapter: 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan

2 Document title: Status: Draft Report Date: 21 August 2014 Project name: York Potash Project Project number: PB1110 Client: York Potash Limited Client contact: James Barrie Reference: PB1110/Outline SMP/303250/Lond Drafted by: Alison Hallas Checked by: John Bevan, Phil Williamson Date / initials check: 17 September 2014 Approved by: Date / initials approval: Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan i

3 Summary This document forms the Outline Soil Management Plan (SMP) for the York Potash Project. It is intended to provide further information to the Local Planning Authorities regarding soil management best practice and mitigation as described in the various ES chapters and how it will be implemented during the construction phase. It includes generic best practice soil management measures and specific measures focused on the characteristics of soils found on each site and the proposed earthworks and reinstatement. An updated full SMP will be completed once the earthworks contractors have been appointed and design finalised in order to ensure that the method statements are developed with full consideration of their proposed working methods and can therefore suitable for application throughout the earthworks period. Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan ii

4 Summary... ii 1 Introduction The York Potash Project Site Location and Description Management Plan Purpose Management Plan Structure Soil Management Best Practice Mine Surface Development Site Soil Management Plan Description of baseline Summary of Proposed Earthworks Summary of Restoration and End Use Specific requirements for soil management at the site Lady Cross Plantation Site Soil Management Plan Description of baseline Summary of Proposed Earthworks Summary of Restoration and End Use Specific requirements for soil handling at the site Lockwood Beck site Soil Management Plan Description of baseline Summary of Proposed Earthworks Summary of Restoration and End Use Specific requirements for soil management at the site Tocketts Lythe site Soil Management Plan Description of baseline Summary of Proposed Earthworks Summary of Restoration and End Use Specific requirements for soil handling at the site Figures Appendix 1: Soil Resources, Agricultural Use and Quality of Land Reports Appendix 2: Mine Surface Development Site Earthworks Phasing Documents Appendix 3: YPP 100 Year Decommissioning Strategy report Appendix 4: Lady Cross Plantation Site Earthworks Phasing Documents Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan iii

5 Appendix 5: Lockwood Beck Site Earthworks Phasing Documents Appendix 6: Tocketts Lythe Site Earthworks Phasing Documents Appendix 7: Earthworks Best Practice Method Sheets Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan iv

6 1 Introduction 1.1 The York Potash Project York Potash Limited (YPL), a subsidiary of Sirius Minerals plc., intends to develop a mining operation situated in North Yorkshire to Mine the world class deposits of polyhalite mineral found here. The York Potash Project (YPP) area lies between Scarborough and Whitby, extending approximately 16 kilometres inland from the coast and up to 14km offshore (Figure 1). 1.2 Site Location and Description The onshore aspects of the project comprise a series of elements: The Mine, the surface works and ancillary facilities for which are located at the Mine surface development, near Whitby. The Materials Transport System, to be installed within a tunnel below ground, will extend approximately 36.5km from the Mine surface development site to the Wilton site at Teesside where the Materials Handling Facility (MHF) will be located. There will be three intermediate shafts installed along the route located approximately 9km, 24km and 29km from the Mine site where spoil from construction of the tunnel will be deposited. The depth of the tunnel will vary between 360m and 120m below the surface at the shaft sites. Port facilities will be located at Bran Sands at Teesside. In addition, Construction Accommodation and Construction Park and Ride facilities will be located 1.6km to the south of Whitby with the Operational Park and Ride located 2km to the east of Whitby. The Mine and intermediate shaft sites are located in agricultural areas. At these sites, the surface deposits comprise predominantly natural topsoil and subsoil. Intrusive soil resource surveys have been completed at these sites to gather information on the nature of the soils present and support the development of a Soil Management Plan (SMP) for use during the construction phase earthworks. The Wilton site is in industrial use and, in large part, is previously developed. It has significant deposits of made ground (ground which has been previously excavated/reworked and contains anthropogenic materials such as brick, concrete, coal, clinker and pottery). However, some areas of the site contain natural soils. The port site comprises previously industrial land (made ground) and hence no SMP is necessary. At the park and ride facilities, some earthworks are expected. Best practice for handling natural soils is provided in Section 2 for these sites to help preserve this resource. 1.3 Management Plan Purpose This document forms the Outline Soil Management Plan (SMP) for the York Potash Project. It is intended to provide further information to the Local Planning Authorities regarding soil management best practice and mitigation as described in the various ES chapters and how it will be implemented during the construction phase. The full SMP will be completed once the earthworks contractors have been appointed in order to ensure that the method statements are developed with full consideration of Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 1

7 their proposed working methods and are therefore suitable for application throughout the earthworks period. The full SMP will provide recommendations on land access, soil handling and erosion control for excavations at each of the sites where significant excavations of natural soil will be undertaken. The recommendations will be based upon the findings and interpretation of the soil surveys conducted between March and April 2014 by Land Research Associates (reports reference 932/1c, 932/2a, 932/4a and 932/3a Appendix 1). The mitigation measures above would be set out in a Soil Management Plan (SMP), including construction method statements for soil handling, which would be produced by a competent soil science contractor and agreed with the relevant regulator, in advance of the works. This would be completed pre-construction once an earthworks contractor has been appointed and detailed earthworks phasing information is available. The contractor would be required to comply with the SMP. No detailed soil management plan is necessary for soils of the woodland areas. The only site where significant earthworks are planned for woodland soils is the Mine surface development site. Here, the woodland soils were found to be a poor quality resource (see Section 3). 1.4 Management Plan Structure The remainder of this Outline SMP follows the following structure: Section 2: Soil management best practice Section 3: Mine surface development site SMP Section 4: Lady Cross Plantation Site SMP Section 5: Lockwood Beck Site SMP Section 6: Tocketts Lythe Site SMP Each site SMP has been presented as a standalone document for completion prior to mobilisation of the earthworks contractors and use throughout the earthworks. 2

8 2 Soil Management Best Practice The following best practice guidance and techniques will be applied throughout the York Potash Project, on all sites where earthworks are undertaken. The earthworks will be completed in general accordance with the following guidance: Defra (2009) Construction Code of Practice for the Sustainable Use of Soils on Construction Sites. MAFF (2000) Good Practice Guide for Handling Soils. General mitigation measures which will be applied at each of the YPP sites include: Soils handling, storage and reinstatement must be undertaken by a competent and suitably experienced contractor; Topsoil will be stored adjacent to where it is extracted, wherever practical; Excavated subsoil will be stored separately from the topsoil, with sufficient separation to ensure segregation; Soils should be handled according to their characteristics e.g. within wooded areas it is unlikely that topsoil resources of any quality could be separated and preserved for reuse. If current wooded areas are to be used for storage it would not be necessary to undertake topsoil stripping. Topsoils from agricultural land may be treated as a single resource for stockpiling and reuse (see Appendix 1); Where under storage areas, loosening of subsoils is proposed when dry to improve permeability before the topsoil is replaced; For most after-uses, subsoils may be treated as a single resource for stockpiling; During wet periods, limiting mechanised soil handling in areas where soils are highly vulnerable to compaction; Restricting movements of heavy plant and vehicles to specific routes and avoidance of trafficking of construction vehicles in areas of the site which are not subject to construction phase earthworks. Minimising the excavation footprint where possible; and In circumstances where construction has resulted in soil compaction, further remediation may be provided, through an agreed remediation strategy. 3

9 3 Mine Surface Development Site Soil Management Plan 3.1 Description of baseline The detailed survey undertaken of Soil Resources and Agricultural Use and Quality of Land (Appendix 1) confirmed that heavy clay loam topsoil was encountered in the west and north east of the site, overlying dense slowly permeable clay subsoil, with a thin intervening layer of moderately permeable upper subsoil in some locations. The remainder of the agricultural areas of the site were found to have medium clay loam soils, usually overlying heavier slowly permeable subsoils. A representative profile of the heavy loamy over clayey soils is: m Dark greyish brown heavy clay loam with many distinct fine red root channel mottles; very slightly stony; moderately developed coarse sub-angular blocky structure; friable to firm. There was an abrupt smooth boundary to the next layer m Grey (clay with many distinct strong brown mottles; stoneless or very slightly stony; weakly developed very coarse prismatic to massive structure; very firm. There was a gradual smooth boundary to the next layer m+ Strong brown heavy clay loam with many distinct coarse grey mottles; stoneless; massive (structureless). A representative profile of the medium fine loamy soils is: m Very dark greyish brown medium clay loam; very slighty stony; well-developed medium to coarse sub-angular blocky structure; friable. There was an abrupt smooth boundary to the next layer m Greyish brown sandy clay loam with abundant distinct fine brownish grey and yellowish brown mottles; slightly stony; moderately developed medium to coarse angular blocky structure; friable. There was a clear smooth boundary to the next layer m+ Grey heavy clay loam with abundant coarse strong brown mottles; slightly stony; weak very coarse angular blocky to prismatic structure; firm. Soils in the woodland areas were found to be highly variable but mainly of similar types to the agricultural soils (fine loamy soils or fine loamy over clayey soils), often with an organic/peaty upper horizon. The soil types identified are shown in the Soil Resources and Agricultural use and Quality report for the site (Appendix 1). The soil survey of the site concluded that the topsoil in agricultural areas is a clay loam and therefore whilst naturally fertile, is also susceptible to compaction, and difficult to handle during wet periods using machinery without causing structural degradation. Subsoil was noted generally to be highly susceptible to compaction (see Appendix 1) due to its clayey and loamy composition. Two subsoil resources exist at the site: a moderately permeable upper subsoil of fine loamy soils and a slowly permeable material found below 50cm in the fine loamy soils or immediately below the topsoil in the clay soils (see Map 1 in the Soil Resources and Agricultural use and Quality report for the site - Appendix 1). Soils of the woodland areas were noted to be of low quality and unlikely to be degraded further by mechanised handling. The soils under plantation are variable and often previously disturbed by forestry operations. 4

10 3.2 Summary of Proposed Earthworks The earthworks phasing plans, volume calculations and outline method statements are provided in Appendix 2. The outline method statements will be revised and updated following appointment of the earthworks contractors. Table 3.1 Key features of the earthworks Mine surface development site Description Timescale Drawing reference A series of permanent landscaped bunds will be formed and shallow excavations made for surface water attenuation ponds, building foundations and construction platforms. Material will be excavated from depth for the Mine workings. Soils will be stored in temporary stockpiles. - YP-P2-CX-030 The bunds will be formed using spoil excavated from the Mine workings, subsoil and topsoil. The volumes of each material to be used in each bund and each pond excavation have been provided - YP-P2-CX-032 Excavations and fill requirements for construction platform areas have also been provided - YP-P2-CX-033 The earthworks will progress in 7 phases with topsoil and subsoil progressively stripped as required to accommodate spoil deposition and development infrastructure. Plans for each phase and a summary of works have been provided - YP-P2-CX-034 and YP-P2-CX-034 Phase 1 will include the following earthworks: Soil stripping and formation of the site access road Soil stripping and reuse for formation of temporary surface water attenuation ponds Soil stripping, formation and restoration of two noise attenuation bunds Soil stripping for two permanent spoil deposition bunds Placement of inert material from the shaft platform area in permanent bunds and in formation of attenuation ponds (clay liner) Months 1 to 6 YP-P2-CX-070 to YP-P2-CX-073 5

11 Description Timescale Drawing reference Power cable diversion Restoration of part of bund F and commencement of restoration of a second bund (D) Phase 2 will include the following earthworks: Re-engineering of site won clay and placement of pyritic mudstone in spoil deposition bund (D) Soil stripping and formation of temporary inert material stockpile Soil stripping from welfare buildings area Placement of spoil in bund (E) and commencement of restoration Months 7 to 17 YP-P2-CX-074 Phase 3 will include the following earthworks: Completion of restoration of bund E Completion of spoil placement and restoration of the remainder of bund D Re-engineering of site won clay for containment of bund H and placement of pyritic mudstone Restoration of the exhaust ventilation shaft area (bund I) Temporary stockpiling of non-hazardous non inert material Months 18 to 24 YP-P2-CX-075 Phase 4 will include the following earthworks: Re-engineering of site won clay for containment of the north east of bund F, placement of pyritic mudstone and restoration Subsoil stripping and excavation of inert superficial deposits from the welfare buildings area. Temporary stockpiling of the inert material Soils stripping and placement or stockpiling of non-hazardous non inert material in bund C Temporary stockpiling of non-hazardous non inert material Months 25 to 32 YP-P2-CX-076 6

12 Description Timescale Drawing reference Phase 5 will include the following earthworks: Re-engineering of site won clay for containment and restoration of west and south of bund C Placement of spoil in the east of bund C Months 33 to 40 YP-P2-CX-077 Phase 6 will include the following earthworks: Temporary stockpiling of non-hazardous non inert material in the east of bund C Completion of bund H using stockpiled inert material Restoration of bunds G and H Restoration of soil on the temporary stockpile area Months 41 to 46 YP-P2-CX-078 Phase 7 will encompass the completion of spreading of soils from the temporary stockpile site (east of bund C) to the final restoration contours (minimal earthworks) - YP-P2-CX-079 Volumes of materials movements are provided in the Earthworks Strategy Volumes spreadsheet in Appendix Summary of Restoration and End Use During the operational life of the Mine, the areas of the site not used for mining and associated infrastructure would be restored to landscaping and habitat creation. Following decommissioning, the land would be restored to agricultural, forestry or amenity use (potentially including nature conservation). Further information is provided in the YPP 100 Year Decommissioning Strategy report (Appendix 3). The landscape restoration plan for the site (including soil restoration depths) has been designed for these end uses. The preservation of the soil resource and protection of soil structure at the site will be important in order to achieve suitable restored soil conditions for these land uses. 3.4 Specific requirements for soil management at the site Management of agricultural soils The topsoil of the land is a resource of moderate quality; it is naturally fertile, but susceptible to compaction when wet. Topsoils of the agricultural land may be treated as a single resource for stockpiling and reuse. 7

13 The better-draining soils at the site have moderately permeable upper subsoil, which is highly susceptible to compaction and sealing which will increase runoff. The heavier soils have naturally slowly permeable occurring immediately below the topsoil, but are susceptible to compaction which can cause sealing and severe wetness problems. In both cases therefore, where under storage areas subsoils require loosening when dry to improve permeability before the topsoil is replaced. Timing of mechanised operations (including loosening) is critical to avoid degradation. Two subsoil resources exist at the site: i) the moderately permeable upper subsoil of fine loamy soils and ii) slowly permeable material found below 50 cm in the fine loamy soils or immediately below the topsoil in the clay soils (see Map 1 in the Soil Resources and Agricultural use and Quality report for the site - Appendix 1). For most after-uses, subsoils may be treated as a single resource for stockpiling. Areas not being built over should not be trafficked by construction vehicles as this will render the soils impermeable, preventing percolation of rainfall beyond the base of the topsoil, which will quickly become saturated. Stripped topsoil should be stored in separate resource bunds, preferably no more than 3-4 m high, kept grassed and free from construction traffic until required for re-use. The Construction Code of Practice for Sustainable Use of Soils on Construction Sites (Defra 2009) provides guidance on good practice in soil handling Management of woodland soils The soils under plantation are variable and often previously disturbed by forestry operations. Attempts to strip soils from woodland areas to be used for soil stockpiling and other activities relating to the mining operations would first require tree stump removal, and given the fact the soils are heavy and undrained, it is highly unlikely that topsoil resources of any quality could be separated and preserved for reuse. Due to the low quality of the baseline soil resource, where currently wooded areas are to be used for storage it is not necessary to undertake topsoil stripping. Where these soils are to be excavated to install infrastructure they should be stockpiled separately from better quality soils of agricultural areas, and preserved for lower demand uses following reinstatement Soil Handling Soil quality can be impaired by incorrect handling, separation, storage and replacement. Particular problems arise from: Handling soils at inappropriate moisture content. Inappropriate use of machinery. Incorrect topsoil stripping depth resulting in dilution with underlying subsoil. Failure to separate contrasting subsoil layers resulting in impaired drainage and/or reduced soil moisture storage. Poor storage separation resulting in mixing. Excess stockpile height leading to compaction damage, runoff and erosion. 8

14 The ease of soil handling is affected by soil type. Heavy clay soils are difficult to handle when wet without causing structural damage. Conversely sandy soils are resistant to handling damage across a range of moisture contents. Generally the risk of soil handling damage during wet conditions can be minimised by careful attention to the restrictions described in and of this report. Mechanised soil handling will only take place when soils are below plastic limit in accordance with the MAFF Good Practice Guide for Handling Soils. Before soil handling during winter months and following heavy rain at other times, the moisture status of the soils will be checked by the operator. Stripping should only take place using an excavator as described by Sheet 1 in the MAFF Good Practice Guide for Handling Soils (see Appendix 7). [To be completed in discussion with the appointed contractor to agree acceptable earthworks activities during winter months.] Topsoil and subsoil resources should be stripped and stored separately heaps 3-4m in height, avoiding over-compaction. Topsoil should be stripped to depths provided for each area of the site (see Appendix xx of this report [to be completed]), which will avoid dilution with subsoil. In most places there is a distinct colour difference between topsoil and subsoil that should aid accurate stripping. Where land will be restored to agricultural or forestry use, upper subsoil should be stripped to a depth of 0.25 m and stockpiled separately from underlying material, taking care to replace in the correct order. The following methods should be followed to ensure that suitable conditions exist and that damage to soils is minimised: Machinery operation: a tracked hydraulic excavator should be used to load topsoil and subsoil. The soils should be stripped, stockpiled, removed from storage (Sheet 3 in the MAFF Good Practice Guide) and replaced by tracked hydraulic excavator using the loose tipping technique (Sheet 4 in MAFF Good Practice Guide see Appendix xx), with only gentle firming by tracked vehicles. Rainfall during operations: during rainfall and soon after it ceases there will always be surplus water in the surface layers of soil. If earthmoving continues the surface layer will become compacted, ruts will be formed and any further rain will lie on the surface and tend to drain away far more slowly than previously. Conditions will then tend to deteriorate further during earthmoving with consequential damage to soils. Consequently, soil stripping should be suspended wherever possible during heavy rainfall. After rainfall, the wetness of the soil should be checked (by the earthworks contractor) before recommencing mechanised soil handling. Detailed, site specific methods sheets for soil handling are provided in Appendix 7. [To be completed in discussion with the appointed contractor to agree acceptable earthworks activities during winter months] Prevention of erosion Given the soil types present at the site, risk of erosion is generally low. However, soil erosion by water can be initiated even on gentle slopes and heavy soils where inappropriate management is applied. Even in the absence of significant erosion on these areas, surface runoff can initiate erosion on adjoining susceptible land, particularly when exacerbated by surface compaction or the creation of channels which concentrate runoff (e.g. furrows or vehicle tracks). General erosion management principles should apply to the site: 9

15 Minimise the amount of bare soil. Where possible, avoid operations in heavy rainfall or commencing operations when heavy rainfall is predicted. Avoid soil compaction damage and loosen soils where this occurs (as detailed in soil handling plan Method Sheet see Appendix 7 [to be completed]). Leave bare surfaces rough to encourage infiltration and minimise surface runoff. Grass seeding of all soil stockpiles that would be in place for more than 12 months. This relates to temporary soil stockpiles in place for more than 12 months and permanent spoil storage mounds Compliance monitoring Compliance monitoring will be required during and after construction. An example programme for each stage is outlined below. During construction Visual observation of soil trafficking, stripping, storage and reinstatement methods should be made on the commencement of work by a suitably qualified professional. A limited number of pit excavations to quality-control newly reinstated soils following restoration. Audit of contractor against this SMP and if necessary suggested improvements provided to contractor Following completion Initial compliance monitoring following reinstatement of soils should include visual assessment at selected locations. Visual assessment should include evidence of erosion and of surface wetness which may indicate drainage/compaction problems. A limited number of pit excavations may be made to evaluate potential compaction/drainage problems where identified. Should any specific problems be reported by neighbouring landowners, these should be thoroughly investigated and remediation strategies employed as appropriate. Continuing monitoring can then be employed where necessary Mitigation and Remediation Remediation should not be necessary if the SMP detail is adhered to. However, should any problems be identified, it is important that the causes are correctly identified. Soil erosion Where erosion has initiated on disturbed areas it may be appropriate to install control structures or barriers to check the flow of runoff, and/or loosen compacted surfaces to encourage infiltration on vehicle traffic areas (details are provided in the accompanying Method Sheets; see Appendix 7 [to be completed]). In the event that major erosion has already occurred, specialist advice should be sought on remediation. Soil compaction 10

16 Areas used as haul roads will be ripped (mechanical breaking up of the soil surface) to loosen subsoils prior to topsoil replacement. Compaction damage following soils reinstatement may be evidenced by standing water at the land surface, or by poor plant growth, resulting either from soil waterlogging or drought stress due to inhibited rooting depth. Where compacted subsoil layers are observed, they should be loosened/ripped using commercial subsoiling equipment (e.g. a winged tine). 4 Lady Cross Plantation Site Soil Management Plan 4.1 Description of baseline Soil surveys at the Lady Cross Plantation site identified that topsoils are present within the site and these, along with the upper subsoils, have a sandy clay loam or medium clay loam texture (see Appendix 1). Observations made by hand augering confirmed the following characteristics of the soil: At 0-0.2m depth the soil was black, slightly stony with a well-developed medium and fine subangular structure. There was a clear smooth boundary to the next colour variation. At m depth the soil is greyish brown in colour and sandy clay loam in texture. The soil also has many distinct medium brownish yellow and yellowish red mottles, is slightly stony and has a weakly developed medium to coarse sub-angular block structure. The soil is grey in colour with a heavy clay loam texture. There are also many distinct medium yellowish red and reddish yellow mottles at m depth. At m the soil has a medium clay loam texture and is brown in colour with common distinct fine grey mottles. Woodland areas within the sites are limited to approximately 0.21 ha at Lady Cross Plantation. Woodland soils have therefore not been considered further as a separate resource. 4.2 Summary of Proposed Earthworks The earthworks phasing plans, volume calculations and outline method statements are provided in Appendix 4. The outline method statements will be revised and updated following appointment of the earthworks contractors. Table 4.1 Key features of the earthworks Lady Cross Plantation Description Timescale Drawing reference One permanent landscaped spoil deposition bund will be formed and shallow excavations made for surface water attenuation ponds, building foundations and construction platforms. Material will be excavated from depth for the Mine shaft. Soils will be stored in temporary stockpiles. The bunds will be formed using spoil excavated from the Mine shaft, subsoil and topsoil. The - YP-P2-CX YP-P2-CX

17 Description Timescale Drawing reference volumes of each material to be taken from each excavation and used in each bund have been provided The earthworks will progress in 6 phases with topsoil and subsoil progressively stripped as required to accommodate spoil deposition and development infrastructure. A plan summarising the works within each stage and the locations of works within each stage has been provided. Further detail of the earthworks phasing within the spoil deposition mound has also been provided Month 3 to 41 Months 3 to 38 YP-P2-CX-442 YP-P2-CX-443 Volumes of materials movements are provided in the Earthworks Strategy Volumes spreadsheet in Appendix Summary of Restoration and End Use Operational phase infrastructure will be contained within an area covering 1 ha at each site; the remainder will be returned to either agricultural use, habitat enhancement or possibly amenity use (land may be used to create a network of footpaths for use by the general public including those staying at the nearby caravan park). The operational phase site layout is shown on drawings YP-P2-CX-441 in Appendix Specific requirements for soil handling at the site Soil Management Topsoil The fine loamy topsoil covering much of the site is a resource of moderate quality if retained for use in landscaping; it is susceptible to compaction if handled when wet and therefore, wherever possible, handling should not occur during or within 24 hours after heavy rain. Other than heavy rainfall periods, soil conditions are usually suitable for topsoil stripping and stockpiling between the beginning of May and the end of September at this site. Outside of this period, soils are likely to be wet for long periods and therefore susceptible to structural damage. At these times mitigation techniques to avoid damage in wet conditions should be employed, as described in section Where possible, stripped topsoil should be stored in separate resource bunds no more than 3-4 m high, and kept grassed and free from construction traffic until required for re-use. Subsoil 12

18 The soils have permeable upper subsoil of slightly variable depth, which is a better quality resource than the lower subsoil for soil profile restoration. Stripping and separate storage of this material to a depth of 20 cm following topsoil removal would provide for the creation of better-draining soil profiles if required. For other uses (such as restoration to woodland plantation or habitat areas) subsoils may be stripped and reused as a single resource. Subsoils will benefit from loosening before topsoil replacement. If soil is to be handled when wet, the recommended method is to strip topsoil and subsoil in narrow sections using an excavator. Dozers should not be used in these soil conditions. Transport vehicles should only run on the basal layer (i.e. on the ground surface following stripping of subsoil to the required stockpiling depth), thus avoiding compaction damage. Soil conditions should be checked prior to handling operations and should not proceed if soils are found to be waterlogged. The Construction Code of Practice for Sustainable Use of Soils on Construction Sites (Defra 2009) provides full details of recommended methods Soil Handling Soil quality can be impaired by incorrect handling, separation, storage and replacement. Particular problems arise from: Handling soils at inappropriate moisture content. Inappropriate use of machinery. Incorrect topsoil stripping depth resulting in dilution with underlying subsoil. Failure to separate contrasting subsoil layers resulting in impaired drainage and/or reduced soil moisture storage. Poor storage separation resulting in mixing. Excess stockpile height leading to compaction damage, runoff and erosion. The ease of soil handling is affected by soil type. Heavy clay soils are difficult to handle when wet without causing structural damage. Conversely sandy soils are resistant to handling damage across a range of moisture contents. Generally the risk of soil handling damage during wet conditions can be minimised by careful attention to the restrictions described in Section of this report. Stripping should only take place using an excavator as described by Sheet 1 in the MAFF Good Practice Guide for Handling Soils (see Appendix 7 [to be completed]). Topsoil should be stripped to depths provided for each area of the site (see Appendix 7 of this report [to be completed]), which will avoid dilution with subsoil. In most places there is a distinct colour difference between topsoil and subsoil that should aid accurate stripping. Upper subsoil should be stripped to a depth of 20 cm and stockpiled separately from underlying material, taking care to replace in the correct order. The following stages should be followed to ensure that suitable conditions exist and that damage to soils is minimised: 13

19 Machinery operation: a tracked hydraulic excavator should be used to load topsoil and subsoil. The soils should be stripped, stockpiled, removed from storage (Sheet 3 in the MAFF Good Practice Guide see Appendix 7 [to be completed]) and replaced by tracked hydraulic excavator using the loose tipping technique (Sheet 4 in MAFF Good Practice Guide see Appendix 7 [to be completed]), with only gentle firming by tracked vehicles. Rainfall during operations: during rainfall and soon after it ceases there will always be surplus water in the surface layers of soil. If earthmoving continues the surface layer will become compacted, ruts will be formed and any further rain will lie on the surface and tend to drain away far more slowly than previously. Conditions will then tend to deteriorate further during earthmoving with consequential damage to soils. Consequently, soil stripping should be suspended during heavy rainfall wherever possible. After rainfall, the wetness of the soil should be checked (by the earthworks contractor) before recommencing mechanised soil handling. Detailed methods sheets for soil handling are provided in Appendix 7 [to be completed] Prevention of erosion Given the soil types present at the site, risk of erosion is generally low. However, soil erosion by water can be initiated even on gentle slopes and heavy soils where inappropriate management is applied. Even in the absence of significant erosion on these areas, surface runoff can initiate erosion on adjoining susceptible land, particularly when exacerbated by surface compaction or the creation of channels which concentrate runoff (e.g. furrows or vehicle tracks). General erosion management principles should apply across the site: Minimise the amount of bare soil. Avoid operations in heavy rainfall or commencing operations when heavy rainfall is predicted. Avoid soil compaction damage and loosen soils where this occurs (as detailed in soil handling plan Method Sheet see Appendix 7 [to be completed]). Leave bare surfaces rough to encourage infiltration and minimise surface runoff. Grass seeding of all soil stockpiles that would be in place for more than 12 months. This relates to temporary soil stockpiles in place for more than 12 months and permanent spoil storage mounds Compliance monitoring Compliance monitoring will be required during and after construction. An example programme for each stage is outlined below. During construction Visual observation of soil trafficking, stripping, storage and reinstatement methods should be made on the commencement of work by a suitably qualified professional. A limited number of pit excavations to quality-control newly reinstated soils following restoration. Audit of contractor against this SMP and if necessary suggested improvements provided to contractor 14

20 Following completion Initial compliance monitoring following completion should include visual assessment at selected locations. Visual assessment should include evidence of erosion and of surface wetness which may indicate drainage/compaction problems. A limited number of pit excavations may be made to evaluate potential compaction/drainage problems where identified. Longer-term monitoring should include a rapid reconnaissance at selected locations within the site once restoration is complete and planting in areas of habitat or grass/crops in agricultural areas have established. Visual indicators of poor plant/crop performance (relative to surrounding areas outside the site) can be used to assess potential damage which may then be investigated in further detail. Should specific problems be reported by landowners, these need to be thoroughly investigated and remediation strategies employed as appropriate. Continuing monitoring can then be employed where necessary Mitigation and Remediation Remediation should not be necessary if the management plan detail is adhered to. However, should agricultural management problems be identified by landowners/operators in the season following restoration and returning of the site to its end use, it is important that the causes are correctly identified. Soil erosion Where erosion has initiated on disturbed areas it may be appropriate to install control structures or barriers to check the flow of runoff, and/or loosen compacted surfaces to encourage infiltration on vehicle traffic areas (details are provided in the accompanying Method Sheets; see Appendix 7 [to be completed]). In the event that major erosion has already occurred, specialist advice should be sought on remediation. Soil compaction Areas used as haul roads should be ripped (mechanical breaking up of the soil surface) to loosen subsoils prior to topsoil replacement. Compaction damage following soils reinstatement may be evidenced by standing water at the land surface, or by poor plant/crop growth, resulting either from soil waterlogging or drought stress due to inhibited rooting depth. Existence of over-compacted layers should be initially assessed by inspection of shallow pits. This is particularly important in establishing cause with reference to damage to drainage systems as described below. Where compacted subsoil layers are observed, they should be loosened/ripped using commercial subsoiling equipment (e.g. a winged tine). Specialist grassland subsoilers (which minimise vegetation disturbance) are also commercially available. Should compaction damage occur in areas which are restored to grass, it may be additionally necessary to cultivate the topsoil and reseed to grass to remove near-surface compaction. Topsoil compaction will be removed automatically by cultivation in arable fields and is therefore unlikely to be an issue. 15

21 Damaged drainage systems In temporary construction areas, breakage or blockage of field drainage systems is likely to be evidenced by wet patches at the soil surface upslope of excavation areas. These may be tens of metres away from the area of disturbance, but any wetness occurring downslope or more than 50 m upslope should be assumed to be unrelated to construction activities. Surface ponding can also be caused by soil compaction, but where ponding occurs in dry periods it is likely to be due to drain damage. Where the cause is uncertain it will be ascertained by a small pit excavation. Drainage problems unrelated to surface compaction should be referred to a specialist drainage contractor. A new drainage system will be installed under landscaped spoil deposition areas. 16

22 5 Lockwood Beck site Soil Management Plan 5.1 Description of baseline Topsoils at the Lockwood Beck site were identified as sandy clay loams or clay loams which usually overlie moderately permeable fine loamy upper subsoil. Slowly permeable subsoil mostly occurs at a depth of m below the surface. In some areas the slowly permeable subsoils lay directly below the topsoil (see Appendix 16.1). Observations made by hand augering confirmed the presence of soil which has the following characteristics: From m below the surface the soil is a very dark greyish brown sandy clay loam. This is stoneless with distinct reddish brown root channel mottles and a moderately developed sub-angular blocky structure. At m depth the soil becomes a light brownish grey stoneless sandy clay loam with, many distinct reddish brown mottles, and a weak coarse angular blocky structure. The soil at m depth is a stoneless grey dense heavy clay loam with a very coarse angular blocky to prismatic structure which has a gradual smooth boundary to reddish brown dense silty clay at m depth. Woodland areas within the sites are limited to 0.1ha at Lockwood Beck. Woodland soils have therefore not been considered further as a separate resource. 5.2 Summary of Proposed Earthworks The earthworks phasing plans, volume calculations and outline method statements are provided in Appendix 5. The outline method statements will be revised and updated following appointment of the earthworks contractors. Table xx Key features of the earthworks Lockwood Beck Description Timescale Drawing reference Two permanent landscaped spoil deposition bunds will be formed and shallow excavations made for surface water attenuation ponds, building foundations and construction platforms. Material will be excavated from depth for the Mine shaft. Soils will be stored in temporary stockpiles. The bunds will be formed using spoil excavated from the Mine shaft, subsoil and topsoil. The volumes of each material to be taken from each excavation and used in each bund have been provided - YP-P2-CX YP-P2-CX-433 The earthworks will progress in 6 phases with topsoil and subsoil progressively stripped as required to accommodate spoil deposition and Month 3 to 46 YP-P2-CX

23 Description Timescale Drawing reference development infrastructure. A plan summarising the works within each stage and the locations of works within each stage has been provided. Further detail of the earthworks phasing within the spoil deposition mounds has also been provided Months 3 to 38 YP-P2-CX-423 Volumes of materials movements are provided in the Earthworks Strategy Volumes spreadsheet in Appendix Summary of Restoration and End Use Operational phase infrastructure will be contained within an area covering 1 ha; the remainder will be returned to either agricultural use or habitat enhancement. It is intended that the majority of land at Lockwood Beck would be returned to arable or grassland use. The operational phase site layouts are shown on drawings YP-P2-CX-421 in Appendix Specific requirements for soil management at the site Soil Management Topsoil The fine loamy topsoil of most of the land is a resource of moderate quality; it is naturally fertile, but susceptible to compaction when wet. The coarse loamy topsoils in the north-east are a high quality resource. Fine-textured and coarse-textured topsoils should be stripped and stockpiled separately according to the mapped distribution (see Map 1 in the Soil Resources survey report in Appendix 1: Soil Resources and Agricultural Use and Quality of Land near Stanghow). Subsoil The dominant fine-textured soils at the site (which underlie the whole of the proposed compound area) mainly have moderately permeable upper subsoil, overlying dense, poorly structured subsoil. Stripping of the upper subsoil to a depth of 0.25 m once topsoil has been removed would prevent restored soils developing very poor drainage conditions. Timing of mechanised operations (including loosening) is critical to avoid degradation. The coarse-textured soils have permeable subsoil to depth, which may be usefully used to create good quality restored profiles with free drainage. Areas not being built over should not be trafficked by construction vehicles as this will render the soils impermeable, preventing percolation of rainfall beyond the base of the topsoil, which will quickly become saturated. Stripped topsoil should be stored in separate resource bunds preferably 3-4 m high, kept grassed and free from construction traffic until required for re-use. The Construction Code of Practice for Sustainable Use of Soils on Construction Sites (Defra 2009) provides guidance on good practice in soil handling. 18

24 5.4.2 Soil Handling Soil quality can be impaired by incorrect handling, separation, storage and replacement. Particular problems arise from: Handling soils at inappropriate moisture content. Inappropriate use of machinery. Incorrect topsoil stripping depth resulting in dilution with underlying subsoil. Failure to separate contrasting subsoil layers resulting in impaired drainage and/or reduced soil moisture storage. Poor storage separation resulting in mixing. Excess stockpile height leading to compaction damage, runoff and erosion. The ease of soil handling is affected by soil type. Heavy clay soils are difficult to handle when wet without causing structural damage. Conversely sandy soils are resistant to handling damage across a range of moisture contents. Generally the risk of soil handling damage during wet conditions can be minimised by careful attention to the restrictions described in Section of this report. Stripping should only take place using an excavator as described by Sheet 1 in the MAFF Good Practice Guide for Handling Soils. Topsoil and subsoil resources should be stripped and stored separately in low heaps, avoiding overcompaction. Topsoil should be stripped to depths provided for each area of the site (see Appendix 7 of this report [to be completed]), which will avoid dilution with subsoil. In most places there is a distinct colour difference between topsoil and subsoil that should aid accurate stripping. Upper subsoil should be stripped to a depth of 25 cm and stockpiled separately from underlying material, taking care to replace in the correct order. The following stages should be followed to ensure that suitable conditions exist and that damage to soils is minimised: Machinery operation: a tracked hydraulic excavator should be used to load topsoil and subsoil. The soils should be stripped, stockpiled, removed from storage (Sheet 3 in the MAFF Good Practice Guide) and replaced by tracked hydraulic excavator using the loose tipping technique (Sheet 4 in MAFF Good Practice Guide), with only gentle firming by tracked vehicles. Rainfall during operations: during rainfall and soon after it ceases there will always be surplus water in the surface layers of soil. If earthmoving continues the surface layer will become compacted, ruts will be formed and any further rain will lie on the surface and tend to drain away far more slowly than previously. Conditions will then tend to deteriorate further during earthmoving with consequential damage to soils. Consequently, soil stripping should be suspended during heavy rainfall. After rainfall, the wetness of the soil should be checked (by the earthworks contractor) before recommencing mechanised soil handling. Detailed methods sheets for soil handling are provided in Appendix 7 [to be completed]. 19

25 5.4.3 Prevention of erosion Given the soil types present at the site, risk of erosion is generally low. However, soil erosion by water can be initiated even on gentle slopes and heavy soils where inappropriate management is applied. Even in the absence of significant erosion on these areas, surface runoff can initiate erosion on adjoining susceptible land, particularly when exacerbated by surface compaction or the creation of channels which concentrate runoff (e.g. furrows or vehicle tracks). General erosion management principles should apply across the site: Minimise the amount of bare soil. Avoid operations in heavy rainfall or commencing operations when heavy rainfall is predicted. Avoid soil compaction damage and loosen soils where this occurs (as detailed in soil handling plan Method Sheet see Appendix 7 [to be completed]). Leave bare surfaces rough to encourage infiltration and minimise surface runoff. Grass seeding of all soil stockpiles that would be in place for more than 12 months. This relates to temporary soil stockpiles in place for more than 12 months and permanent spoil storage mounds Compliance monitoring Compliance monitoring will be required during and after construction. An example programme for each stage is outlined below. During construction Visual observation of soil trafficking, stripping, storage and reinstatement methods should be made on the commencement of work by a suitably qualified professional. A limited number of pit excavations to quality-control newly reinstated soils following restoration. Audit of contractor against this SMP and if necessary suggested improvements provided to contractor Following completion Initial compliance monitoring following completion should include visual assessment at selected locations. Visual assessment should include evidence of erosion and of surface wetness which may indicate drainage/compaction problems. A limited number of pit excavations may be made to evaluate potential compaction/drainage problems where identified. Longer-term monitoring should include a rapid reconnaissance at selected locations within the site once restoration is complete and planting in areas of habitat or grass/crops in agricultural areas have established. Visual indicators of poor plant/crop performance (relative to surrounding areas outside the site) can be used to assess potential damage which may then be investigated in further detail. Should specific problems be reported by landowners, these need to be thoroughly investigated and remediation strategies employed as appropriate. Continuing monitoring can then be employed where necessary. 20

26 5.4.5 Mitigation and Remediation Remediation should not be necessary if the management plan detail is adhered to. However, should agricultural management problems be identified by landowners/operators in the season following restoration and returning of the site to its end use, it is important that the causes are correctly identified. Soil erosion Where erosion has initiated on disturbed areas it may be appropriate to install control structures or barriers to check the flow of runoff, and/or loosen compacted surfaces to encourage infiltration on vehicle traffic areas (details are provided in the accompanying Method Sheets; see Appendix 7 [to be completed]). In the event that major erosion has already occurred, specialist advice should be sought on remediation. Soil compaction Areas used as haul roads should be ripped (mechanical breaking up of the soil surface) to loosen subsoils prior to topsoil replacement. Compaction damage following soils reinstatement may be evidenced by standing water at the land surface, or by poor plant/crop growth, resulting either from soil waterlogging or drought stress due to inhibited rooting depth. Existence of over-compacted layers should be initially assessed by inspection of shallow pits. This is particularly important in establishing cause with reference to damage to drainage systems as described below. Where compacted subsoil layers are observed, they should be loosened/ripped using commercial subsoiling equipment (e.g. a winged tine). Specialist grassland subsoilers (which minimise vegetation disturbance) are also commercially available. Should compaction damage occur in grass fields, it may be additionally necessary to cultivate the topsoil and reseed to grass to remove near-surface compaction. Topsoil compaction will be removed automatically by cultivation in arable fields and is therefore unlikely to be an issue. Damaged drainage systems In temporary construction areas, breakage or blockage of field drainage systems is likely to be evidenced by wet patches at the soil surface upslope of excavation areas. These may be tens of metres away from the area of disturbance, but any wetness occurring downslope or more than 50 m upslope should be assumed to be unrelated to construction activities. Surface ponding can also be caused by soil compaction, but where ponding occurs in dry periods it is likely to be due to drain damage. Where the cause is uncertain it will be ascertained by a small pit excavation. Drainage problems unrelated to surface compaction will be referred to a specialist drainage contractor. A new drainage system will be installed under landscaped spoil deposition areas. There is some potential for damage to drainage systems outside of the working areas at Lockwood Beck. Any potential issues will be discussed with the landowner, and requirements for appropriate diversion structures agreed. 21

27 6 Tocketts Lythe site Soil Management Plan 6.1 Description of baseline The soils at the Tocketts Lythe site were classified as clay loams over silty clays with a high capacity to absorb excess rainfall and to temper pollutants falling on the soil surface during the growing season. However, this capacity is limited in winter when the soil stands wet for long periods. Furthermore, run off risk is high. Observations made by hand augering confirmed the presence of topsoil which has the following characteristics: 0-0.1m Soils have a very dark greyish brown colour which are stoneless and as a well-developed heavy clay loam m The soil is silty clay, a greyish brown colour and with a coarse angular blocky structure m Soils are reddish brown, dense silty clay with a grey ped (soil structure) faces, stoneless and weak very coarse prismatic structure. Woodland areas within the site are limited to 0.01 ha at Tocketts Lythe see Table 16.6). Woodland soils have therefore not been considered further as a separate resource. 6.2 Summary of Proposed Earthworks The earthworks phasing plans, volume calculations and outline method statements are provided in Appendix 6. The outline method statements will be revised and updated following appointment of the earthworks contractors. Table xx Key features of the earthworks Tocketts Lythe Description Timescale Drawing reference One permanent landscaped spoil deposition bund will be formed and shallow excavations made for surface water attenuation ponds, building foundations and construction platforms. Material will be excavated from depth for the Mine shaft. Soils will be stored in temporary stockpiles. The bunds will be formed using spoil excavated from the Mine shaft, subsoil and topsoil. The volumes of each material to be taken from each excavation and used in each bund have been provided - YP-P2-CX YP-P2-CX-418 The earthworks will progress in 6 phases with topsoil and subsoil progressively stripped as required to accommodate spoil deposition and development infrastructure. A plan summarising the works within each stage and the locations of Month 3 to 46 YP-P2-CX

28 Description Timescale Drawing reference works within each stage has been provided. Further detail of the earthworks phasing within the spoil deposition mound has also been provided Months 3 to 30 YP-P2-CX-413 Volumes of materials movements are provided in the Earthworks Strategy Volumes spreadsheet in Appendix Summary of Restoration and End Use Operational phase infrastructure will be contained within an area covering 1 ha; the remainder will be returned to either agricultural use or habitat enhancement. It is intended that the majority of land at Tocketts Lythe would be returned to arable or grassland use. The operational phase site layout is shown on drawings YP-P2-CX-411 in Appendix Specific requirements for soil handling at the site Soil Management Topsoil The fine loamy topsoil of much of the land is a resource of moderate quality if retained for use in landscaping. It is susceptible to compaction if handled when wet and handling should therefore not occur during or within 24 hours after heavy rain. Other than heavy rainfall periods, soil conditions are usually suitable for topsoil stripping and stockpiling between late April and early October at this site. Outside of this period, soils are likely to be wet for long periods and therefore susceptible to structural damage. At these times mitigation techniques to avoid damage in wet conditions should be employed, as described in section Topsoils of the agricultural land may be treated as a single resource for stockpiling and reuse. Subsoil The site has naturally slowly permeable subsoils occurring either immediately below the topsoil or at shallow depth below the land surface. They are susceptible to compaction which can cause sealing and severe wetness problems. Where under storage areas subsoils require loosening (ripping) when dry to improve permeability before the topsoil is replaced, and where excavated and stockpiled they will also benefit from loosening after replacement to improve drainage. Soil handling should be performed according to the schedule described for topsoil above, including the use of mitigation techniques outside of the period from late April to early October. For most after-uses, subsoils may be treated as a single resource for stockpiling. These soils are well suited to mole drainage which will remove ponding in restored profiles where good drainage is desirable (e.g. restoration to agricultural use). 23

29 6.4.2 Soil Handling Soil quality can be impaired by incorrect handling, separation, storage and replacement. Particular problems arise from: Handling soils at inappropriate moisture content. Inappropriate use of machinery. Incorrect topsoil stripping depth resulting in dilution with underlying subsoil. Failure to separate contrasting subsoil layers resulting in impaired drainage and/or reduced soil moisture storage. Poor storage separation resulting in mixing. Excess stockpile height leading to compaction damage, runoff and erosion. The ease of soil handling is affected by soil type. Heavy clay soils are difficult to handle when wet without causing structural damage. Conversely sandy soils are resistant to handling damage across a range of moisture contents. Generally the risk of soil handling damage during wet conditions can be minimised by careful attention to the restrictions described in section Stripping should only take place using an excavator as described by Sheet 1 in the MAFF Good Practice Guide for Handling Soils. Topsoil and subsoil resources should be stripped and stored separately in low heaps, avoiding overcompaction. Topsoil should be stripped to depths provided for each field (see Appendix 7 of this report [to be completed]), which will avoid dilution with subsoil. In most places there is a distinct colour difference between topsoil and subsoil that should aid accurate stripping. Upper subsoil should be stripped to a depth of 60 cm and stockpiled separately from underlying material, taking care to replace in the correct order. The following stages should be followed to ensure that suitable conditions exist and that damage to soils is minimised: Machinery operation: a tracked hydraulic excavator should be used to load topsoil and subsoil. The soils should be stripped, stockpiled, removed from storage (Sheet 3 in the MAFF Good Practice Guide) and replaced by tracked hydraulic excavator using the loose tipping technique (Sheet 4 in MAFF Good Practice Guide), with only gentle firming by tracked vehicles. Rainfall during operations: during rainfall and soon after it ceases there will always be surplus water in the surface layers of soil. If earthmoving continues the surface layer will become compacted, ruts will be formed and any further rain will lie on the surface and tend to drain away far more slowly than previously. Conditions will then tend to deteriorate further during earthmoving with consequential damage to soils. Consequently, soil stripping should be suspended during heavy rainfall wherever possible. After rainfall, the wetness of the soil should be checked (by the earthworks contractor) before recommencing mechanised soil handling. Detailed methods sheets for soil handling are provided in Appendix 7 [to be completed]. 24

30 6.4.3 Prevention of erosion Given the soil types present at the site, risk of erosion is generally low. However, soil erosion by water can be initiated even on gentle slopes and heavy soils where inappropriate management is applied. Even in the absence of significant erosion on these areas, surface runoff can initiate erosion on adjoining susceptible land, particularly when exacerbated by surface compaction or the creation of channels which concentrate runoff (e.g. furrows or vehicle tracks). General erosion management principles should apply across the site: Minimise the amount of bare soil. Avoid operations in heavy rainfall or commencing operations when heavy rainfall is predicted. Avoid soil compaction damage and loosen soils where this occurs (as detailed in soil handling plan Method Sheet see Appendix 7 [to be completed]). Leave bare surfaces rough to encourage infiltration and minimise surface runoff. Grass seeding of all soil stockpiles that would be in place for more than 12 months. This relates to temporary soil stockpiles in place for more than 12 months and permanent spoil storage mounds Compliance monitoring Compliance monitoring will be required during and after construction. An example programme for each stage is outlined below. During construction Visual observation of soil trafficking, stripping, storage and reinstatement methods should be made on the commencement of work by a suitably qualified professional. A limited number of pit excavations to quality-control newly reinstated soils following restoration. Audit of contractor against this SMP and if necessary suggested improvements provided to contractor Following completion Initial compliance monitoring following completion should include visual assessment at selected locations. Visual assessment should include evidence of erosion and of surface wetness which may indicate drainage/compaction problems. A limited number of pit excavations may be made to evaluate potential compaction/drainage problems where identified. Longer-term monitoring should include a rapid reconnaissance at selected locations within the site once restoration is complete and planting in areas of habitat or grass/crops in agricultural areas have established. Visual indicators of poor plant/crop performance (relative to surrounding areas outside the site) can be used to assess potential damage which may then be investigated in further detail. Should specific problems be reported by landowners, these need to be thoroughly investigated and remediation strategies employed as appropriate. Continuing monitoring can then be employed where necessary. 25

31 6.4.5 Mitigation and Remediation Remediation should not be necessary if the management plan detail is adhered to. However, should agricultural management problems be identified by landowners/operators in the season following restoration and returning of the site to its end use, it is important that the causes are correctly identified. Soil erosion Where erosion has initiated on disturbed areas it may be appropriate to install control structures or barriers to check the flow of runoff, and/or loosen compacted surfaces to encourage infiltration on vehicle traffic areas (details are provided in the accompanying Method Sheets ; see Appendix 7 [to be completed]). In the event that major erosion has already occurred, specialist advice should be sought on remediation. Soil compaction Areas used as haul roads should be ripped (mechanical breaking up of the soil surface) to loosen subsoils prior to topsoil replacement. Compaction damage following soils reinstatement may be evidenced by standing water at the land surface, or by poor plant/crop growth, resulting either from soil waterlogging or drought stress due to inhibited rooting depth. Whether compaction damage has occurred as a result of the earthworks should be judged against the performance of the crop in the unaffected area of the field. Existence of over-compacted layers should be initially assessed by inspection of shallow pits. This is particularly important in establishing cause with reference to damage to drainage systems as described below. Where compacted subsoil layers are observed, they should be loosened/ripped using commercial subsoiling equipment (e.g. a winged tine). Specialist grassland subsoilers (which minimise vegetation disturbance) are also commercially available. Should compaction damage occur in grass fields, it may be additionally necessary to cultivate the topsoil and reseed to grass to remove near-surface compaction. Topsoil compaction will be removed automatically by cultivation in arable fields and is therefore unlikely to be an issue. Damaged drainage systems In temporary construction areas, breakage or blockage of field drainage systems is likely to be evidenced by wet patches at the soil surface upslope of excavation areas. These may be tens of metres away from the area of disturbance, but any wetness occurring downslope or more than 50 m upslope should be assumed to be unrelated to construction activities. Surface ponding can also be caused by soil compaction, but where ponding occurs in dry periods it is likely to be due to drain damage. Where the cause is uncertain it will be ascertained by a small pit excavation. Drainage problems unrelated to surface compaction will be referred to a specialist drainage contractor. 26

32 A new drainage system will be installed under landscaped spoil deposition areas. There is some potential for damage to drainage systems outside of the working areas at Tocketts Lythe. Any potential issues will be discussed with the landowner, and requirements for appropriate diversion structures agreed. 27

33 Figures Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 28

34 ± 76; )16: 9, 6)6+- ); ) B 97>6 +78@91/ 0; )6,, ); )*): - 91/ 0; - / - 6, 6; - 95-, 1); - 0).; )6, ; - C?; - 6; 7. $793: ), C? ; - 6; 7. $793: )6,! 79; )4 C?; - 6; 7. $793: )9*7<9 76= -@ - 5?; - 6; 7. $793: Tocketts Lythe!!< / 65-6; 8-9); 176)4 )93 1, - " ) " ) Lockwood Beck 76: ; 9<+; 176 #144)/ 7; - 6; 1)4 0).; 7+); 176: " ) Lady Cross Plantation 41-6; " ) ; &793 7; ): ; 714 )6)/ - 5-6; 4)6 &793 7; ): 0 151; -,!1; 4- &793 7; ): ; <; )6)/ - 5-6; 4)6 )9; / <9- - = ); , 16); )>16/ 7! 9)> , 1A- + )4-91; 1: 0 ); 176)4 91, ROYAL HASKONINGDHV INDUSTRY, ENERGY & MINING ; 9- : ' 8841+); 176: ' & ' % : ' )9; ( ( ), ' 0)8; - 9 ( )6, <: - ( 714: '714( )6)/ - 5-6; ( 4)6' 1/ ( ( ; <; 416- ( ( 5?, B ): 37616/ # " ;, B 97>6 + 78@91/ 0; )6,, ); )*): - 91/ 0; : 9, 6) RIGHTWELL HOUSE BRETTON PETERBOROUGH PE3 8DW +44 (0)

35 Appendix 1: Soil Resources, Agricultural Use and Quality of Land Reports Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 29

36 Appendix 2: Mine Surface Development Site Earthworks Phasing Documents 30

37 Appendix 3: YPP 100 Year Decommissioning Strategy report Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 31

38 Appendix 4: Lady Cross Plantation Site Earthworks Phasing Documents Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 32

39 Appendix 5: Lockwood Beck Site Earthworks Phasing Documents 33

40 Appendix 6: Tocketts Lythe Site Earthworks Phasing Documents 34

41 Appendix 7: Earthworks Best Practice Method Sheets Part 2 Chapter 16 Land Use and Soils Appendix 16.5 Outline Soil Management Plan 35