Key Phase 1 Alconbury Weald, Cambridgeshire Soil ......Key Phase 1 Alconbury Weald, Cambridgeshire...
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Key Phase 1
Alconbury Weald, Cambridgeshire
Soil Resource Plan
Prepared on behalf of:
URBAN & CIVIC LIMITED
TOHA Document Ref: TOHA/14/3918/CS
Document Revision: 04 Document Status: For Construction
Current Issue Date: 5th December 2014
Original Issue Date: 5th November 2014
Prepared by: Tim O’Hare Associates LLP
Howbery Park, Wallingford Oxfordshire, OX10 8BA
Tel: 01491 822653 Email: [email protected]
Web: www.toha.co.uk
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Key Phase 1 Alconbury Weald, Cambridgeshire Tim O’Hare Associates Soil Resource Plan
TOHA/14/3918/CS/Nov
QUALITY MANAGEMENT
Document Title Soil Resource Plan
Project Title Alconbury Weald, Key Phase 1
Client Urban & Civic Limited
Document Ref TOHA/14/3918CS
Document Date 5th December 2014
Prepared By Ceri Spears Signature
Authorised By Tim O’Hare Signature
DOCUMENT DISTRIBUTION
Document Status
Document Issue
Issued To Issue Date
For Information Draft Bradley Murphy Design Ltd 05/11/2014
For Information Issue 01 Bradley Murphy Design Ltd 21/11/2014
For Information Issue 02 Bradley Murphy Design Ltd 27/11/2014
For Information Issue 03 Bradley Murphy Design Ltd 01/12/2014
For Construction Issue 04 Bradley Murphy Design Ltd 05/12/2014
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Key Phase 1 Alconbury Weald, Cambridgeshire Tim O’Hare Associates Soil Resource Plan
TOHA/14/3918/CS/Nov
CONTENTS
Section Page
1 INTRODUCTION ................................................................... 1
2 SITE SOIL RESOURCES .................................................... 2
3 SOIL MANAGEMENT PRACTICES ..................................... 6
4 TREE PIT CONSTRUCTION AND BACKFILLING ............. 14
5 SITE SOIL MONITORING ................................................... 15
Appendix 1 – Key Phase 1 Soil Volume Plan
Appendix 2 – Trial Hole Log
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1. INTRODUCTION
1.1 Background
1.1.1 Key Phase 1 Alconbury Weald is to include residential and commercial development, with
associated retail and community facilities, infrastructure and soft landscape.
1.1.2 The Key Phase 1 area includes the western portion the former Alconbury Airfield and part of the
Enterprise Zone. The old runway runs across the northern part of the phase zone and numerous
aircraft hangars, offices, workshops and former fuel installations are situated around the site.
Aircraft taxiways and several service roads traverse the site. Numerous areas of soft ground
comprising rough grass, with some areas of amenity grass and occasional clusters of trees, are
distributed over the site.
1.1.3 It is the intention to demolish the former airfield infrastructure and buildings and to recover, store
and re-use the existing soil reserves for the soft landscape scheme.
1.2 Reference Material
1.2.1 The following information is to be referenced as part of this Soil Resource Plan.
• Tim O’Hare Associates – Soil Resource Survey Report: Alconbury, Cambridgeshire – Issue 2
(dated January 2012, referenced TOHA/11/3700/CS).
• Alconbury Weald Location Plan (David Lock Associates, ref. UAC002-101)
• Alconbury Weald Parameter Plan (David Lock Associates, ref. UAC002-220)
• Alconbury Weald Topographical Plan (David Lock Associates, ref. UAC002-276)
• Alconbury Weald Key Phase 1 Design Code (DLA, JTP, PBA & Gillespies)
• Alconbury Weald Key Phase 1 Regulatory Plan (David Lock Associates, ref. UAC008-030)
• Alconbury Weald Key Phase 1 Illustrative Masterplan (John Thompson & Partners, ref
00628_SK_23)
1.3 Report Purpose and Limitations
1.3.1 The purpose of the Soil Resource Plan is to outline the strategy for the correct procedures for soil
recovery (stripping and storage), respreading and amelioration as well as treatments for the subsoil
to ensure that a suitable soil profile is produced to help enable healthy root growth and successful
plant establishment.
1.3.2 It has been developed to inform emerging landscape design proposals for the Enterprise Zone and
Key Phase 1-01.
1.3.3 Matters relating specifically to the geotechnical properties of the soils or construction of the
proposed water management infrastructure are outside the scope of this report.
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2. SITE SOIL RESOURCES
2.1 Site Topsoils
2.1.1 The Soil Resource Survey for this site identified significant volumes of topsoil distributed over the
site (see Appendix 1).
2.1.2 1 No. topsoil type was identified within the Key Phase 1 zone. This is referred to as Disturbed
Topsoil.
2.1.3 The Disturbed Topsoil was found to have the following characteristics:
• Topsoil depths ranged from 100mm to 350mm, with an average thickness of 190mm;
• Alkaline to strongly alkaline soil reaction;
• Non-saline;
• Clay to Clay Loam
• Moderately-developed and occasional poorly developed soil structure;
• Low stone content;
• Moderately high organic matter content;
• Sufficient reserves of total nitrogen and extractable magnesium;
• Low extractable phosphorus and extractable potassium content;
• Of the potential contaminants determined, none exceeded their respective SGV or GAC values.
2.1.2 At present the Disturbed Topsoil has adequate soil structures and this shall need to be maintained
for future landscape works.
2.1.4 Providing the physical condition of this topsoil is maintained through the earthworks phase, the
topsoil shall need only routine cultivations prior to re-use.
2.1.5 The deficiencies in extractable potassium and phosphorus shall require amelioration with an
appropriate fertiliser prior to planting, seeding or turfing (except low fertility environments).
2.1.6 The Disturbed Topsoil is would be considered suitable for species-rich grassland establishment on
account of its low phosphorus content.
2.1.7 Selected species shall need to be tolerant of moisture retentive soils. This topsoil would not be
suitable for demanding landscape types such as larger trees (extra heavy standard to semi-mature)
or species which demand free-draining soil.
2.1.8 The Disturbed Topsoil is unsuitable for amenity lawn areas that are expected to receive high levels
of foot traffic on account of its heavy texture.
2.1.9 Selected species shall need to be tolerant of alkaline soils. This topsoil would not be suitable for
species which demand acid or neutral soils.
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2.2 Schedule of Topsoil Volumes
2.2.1 Estimated topsoil volumes for each of the existing soil areas within the Key Phase 1 zone are
shown on the plan presented in Appendix 1 (Key Phase 1 Soil Volume Plan). The total soil areas
and topsoil volume calculation (using the average soil depth) are shown below:
Topsoil Type Area (m2) Average Topsoil Depth (m)
Estimated Topsoil Volume (m3)
Disturbed Topsoil
1035490
0.19
196743.1
(excluding bulking factor)
2.2.2 A bulking factor should be applied to the calculated topsoil volume once excavated. For soils, this
factor can range between approximately +15 to +30% depending on a number factors (e.g.
vegetation content or soil moisture content), at the time of excavation. A bulking factor of +25% is
commonly applied to clay soils. However, the contractor shall determine the bulking factor
allowance with respect to any operational measures or commercial considerations.
2.2.3 The supplied trial hole log is provided in Appendix 2 to indicate the topsoil depth range.
Approximate trial hole locations are indicated on the plan in Appendix 1.
2.3 Site Subsoil
2.3.1 The site subsoil has a clay soil texture. Any damage to the structure of this soil will reduce its
drainage properties. The soakage potential of this soil is likely to be restricted (poorly drained) and
the soil is likely to suffer from seasonal waterlogging, particularly after periods of prolonged or
heavy rainfall.
2.3.2 The subsoil shall need to be left in an uncompacted state after the earthworks phase. This shall
involve deep ripping all subsoil. Provided the subsoil is left with an adequate soil structure, it should
provide sufficient drainage from the topsoil for robust landscape types, woodland planting, hedge
planting (bare root), amenity grass (low foot-traffic areas), wildflower meadow grassland seeding
and marginal / aquatic planting.
2.3.3 Tree and shrub species shall need to be tolerant of moisture retentive soils which are subject to
seasonal waterlogging. This subsoil would not be suitable for demanding landscape types such as
larger trees (extra heavy standard to semi-mature) or species which demand free-draining soil.
2.2.4 The subsoil would also be considered suitable for tree pits for smaller trees (up to heavy standard),
shrub planting, areas of amenity grass in high foot traffic areas and allotments, provided
consideration is given to improving its drainage potential. The level of modification required shall
depend on the local hydrology and the habitat to be constructed.
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2.4 Summary of topsoil suitability
The suitability of the site topsoil for the various proposed planting habitats is summarised on the following
table. Any nutrient deficiencies shall need to be rectified for planting and amenity grass seeding.
Landscape Type Disturbed Topsoil Amelioration/Notes
Rootballed trees - extra heavy standard to semi-mature X N/A
Rootballed trees - up to heavy standard (max. 12-14cm
girth) � Fertiliser application
Shrub planting � Fertiliser application
Woodland planting – planted as whips and transplants � Fertiliser application
Amenity grass seeding (Low foot traffic only) � Fertiliser application
Amenity grass seeding (high foot traffic) X N/A
Hedge planting (bare root) � Fertiliser application
Species-rich grassland � None
Marginal/aquatic planting � None
� – Site Topsoil suitable for this use provided it is adequately structured, aerated and drained and
species selected are tolerant of heavy, moisture retentive, alkaline soils.
O – Site Topsoil may be suitable for this purpose depending on additional considerations.
X – Site Topsoil not suitable for this purpose.
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2.5 Summary of subsoil suitability
The following table summarises the suitability of the site subsoil for use beneath suitable topsoil for a range
of landscape habitats.
Landscape Type Subsoil Amelioration/Notes
Rootballed trees - extra heavy standard to semi-
mature X N/A
Rootballed trees - up to heavy standard (max. 12-
14cm girth) O Improved drainage
Shrub planting O Improved drainage
Woodland planting – planted as whips and
transplants � None
Amenity grass seeding (Low foot traffic only) � None
Amenity grass seeding (high foot traffic) O Improved drainage
Hedge planting (bare root) � None
Species-rich grassland � None
Marginal/aquatic planting � None
� – Site Subsoil suitable for this use provided it is adequately structured, aerated and drained and
species selected are tolerant of heavy, moisture retentive, alkaline soils.
O – Site Subsoil may be suitable for this purpose depending on additional considerations.
X – Site Subsoil not suitable for this purpose.
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3. SOIL MANAGEMENT PRACTICES
3.1 Outline
3.1.1 This section highlights the sequential treatments for the recovery, storage and re-use of the existing
soil resources and the importation, storage and use of imported soils. These practices are based
on the DEFRA Construction Code of Practice for the Sustainable Use of Soils on Construction Sites
(2009).
3.1.2 The strategy for soil stripping, stockpiling and re-use shall be developed with the client/contractor to
support and inform the phasing strategy for Key Phase 1.
3.1.3 Requirements for imported soils are outlined in section 3.6.
3.2 General Site Soil Handling
3.2.1 It is important to avoid soil physical degradation during all phases of soil handling (e.g. stripping,
storage (3.7), respreading (3.9 and 3.10), cultivation (3.8 and 3.11) and planting). Soil handling
operations should ideally be carried out when the soil is reasonably dry and non-plastic (friable) in
consistency (i.e. at least 5% below the soil’s lower plastic limit).
3.2.2 The soils (topsoil and subsoil) shall not be unnecessarily compacted by trampling or trafficking by
site machinery.
3.2.3 If, during the course of the earthworks, the soil is structurally damaged, it shall be suitably cultivated
to relieve the compaction and restore the structure prior to any planting, turfing or seeding.
3.3 Soil Stripping
3.3.1 The topsoil and subsoil (where stripped) shall be stockpiled separately from one another and from
other soils or demolition arisings on the site.
3.3.2 The purpose of vegetation removal is to prevent anaerobic decay of vegetation within the topsoil
stockpile; therefore prior to stripping the topsoil, the existing vegetation shall be removed.
Grass
Grass shall be removed by close mowing followed by collection of the cuttings.
Trees
Trees shall be felled and their trunks removed. The tree stumps shall be removed using suitable
equipment (e.g. tracked excavator with landscape rake or grab) and removed from site. All
branches, brush and ground cover plants shall be removed before shredding.
Couch Grass
Where present, couch grass (Elymus repens) shall be treated by herbicide application to kill the
rhizomes before the topsoil is stripped.
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Prior to stripping the topsoil from affected areas, the couch grass shall initially be sprayed with a
non-residual, non-selective herbicide i.e. Glyphosate. A BASIS qualified contractor should be
appointed to carry out all herbicide treatments. Attention to the requirements under current
C.O.S.H.H. and any other relevant Health and Safety regulations shall be adhered to. The spraying
shall be carried out at least 3 weeks prior to the topsoil strip.
3.3.3 The loose tip method, using dump trucks and hydraulic excavators, shall be used to strip, transport
and stockpile the topsoil and subsoil (where stripped).
3.3.4 The loose-tipping method involves the use of a tracked hydraulic excavator, fitted with a flat edged
grading bucket to strip the soil and load it into a dump truck.
3.3.5 The dump truck, running along a pre-designated route, then transports the soil to the desired
stockpile location.
3.3.6 This operation shall be monitored to ensure that the soil is recovered without the inclusion of other
soils (i.e. topsoil with subsoil) or wastes. Cross contamination with other soil could significantly
degrade the quality of the soils.
3.3.7 Any stones, waste or non-soil materials or spoil heaps shall be removed from areas to be stripped
prior to soil stripping.
3.3.8 Stripping shall ideally be carried out whilst the soil is reasonably dry and friable. However, if due to
construction programme constraints soil stripping needs to be carried out whilst the soil is wet, an
alternative method for soil stockpiling shall be used (Section 3.7.5).
3.4 Depth of Topsoil Strip
3.4.1 The depth of the site topsoil strip shall provisionally be set at 190mm for to enable the majority of
the topsoil to be recovered without the inclusion of significant quantities of subsoil. The trial hole log
is provided (Appendix 2) to indicate the topsoil depth range across the area.
3.4.2 When using an excavator to strip the topsoil, the colour differences between the topsoil and subsoil
can easily be seen by the machine operator carrying out the soil strip so that some discretion can
be made.
3.5 Depth of Subsoil Strip (Where Required)
3.5.1 Where site subsoil is to be stripped, the depth of strip shall provisionally be set at 1.0m below
existing ground level. The trial hole log is provided (Appendix 2) to indicate the subsoil depth range
across the area.
3.5.2 The depth of subsoil strip may vary depending on the amount of ‘cut’ required.
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3.6 Imported Soils
3.6.1 The landscape types that require imported soils are summarised in the table below:
Landscape Type Imported Topsoil Imported Subsoil
Rootballed trees - extra heavy standard to semi-mature � �
Rootballed trees - up to heavy standard (max. 12-14cm
girth) X O
Shrub planting � O
Amenity grass seeding (high foot traffic) � O
� – Imported soil required for this purpose.
O – Imported soil may be required for this purpose depending on additional considerations.
X – Imported soil not required for this purpose. Site-won soil can be used, provided it is adequately structured, aerated and drained
3.6.2 The detailed requirements and testing schedules for the imported soils shall be included within the
soft landscape specification for each development phase.
3.7 Soil Stockpiling
3.7.1 If the programme results in the landscape areas not being ready to receive the topsoil (and subsoil
where necessary) it shall be stored temporarily prior to re-spreading into landscape areas when
they become available.
3.7.2 The soils shall be preferably stored in an area of the site where it shall not interfere with other site
operations so that it can be left undisturbed during other construction activities (proposed soil
storage location TBC). The area that is to be used for storing the soils shall be cleared of
vegetation, in-situ topsoil and any waste arising from the development e.g. building rubble and fill
materials.
3.7.3 The soil shall be transported to the storage area in a dump truck and shall be ‘loose tipped’ in a
series of heaps, starting at the furthest point and working back towards the storage area access.
3.7.4 There are two options for stockpiling the soil depending on the moisture content and plasticity.
These are dry soil stockpiling and wet soil stockpiling.
3.7.5 The wet stockpiling method is illustrated below (Figure 1); the wet soils are tipped for temporary
storage as windrows until the soil has dried out. This technique minimises the amount of
compaction caused by stockpiling as well as maximising the surface area of the stockpile to enable
to soil to dry out. The reconditioning operation would be timed during the summer months (May to
September), to allow enough time for the topsoil to dry out effectively.
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The soil is tipped in a line of heaps to form a
‘windrow’, starting at the furthest point in the
storage area and working back toward the access
point (a).
Any additional windrows are spaced sufficiently
apart to allow tracked plant to gain access between
them so that the soil can be heaped up to a
maximum height of 2.0m (b). To avoid compaction
no machinery, even tracked plant, traverses the
windrow.
Once the soil has dried out and is non-plastic in
consistency (this usually requires several weeks of
dry and windy or warm weather), (c) the windrows
can be combined to form a larger stockpile(s) with a
maximum height of 6.0m, using a tracked excavator
(d).
The surface of the stockpile shall be re-graded and
compacted (e) by a tracked machine (dozer or
excavator) to reduce rainwater infiltration.
Figure 1: Wet Stockpiling Method.
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3.7.6 The dry stockpiling method is illustrated below (Figure 2).
The process requires the topsoil to be transported to the
storage area in a dump truck, and ‘loose tipped’ in a line
of heaps to form a windrow (a).
Once the heaps cover the storage area, a tracked dozer
(e.g. D6 Caterpillar) shall level the heaps to form a level,
stable platform for dump trucks to travel across to tip a
second layer of topsoil. (b and c) This sequence shall be
repeated until the maximum stockpile height is achieved
(d).
Assuming that the topsoil is reasonably dry and friable
during the stripping and storage operation, it shall be
heaped to a maximum of 6.0 metres (health and safety
permitting).
To protect from wet weather once the final height is
achieved, the excavator or blade shall re-grade the sides
and top of the stockpile to firm the surface by tracking
across it to form a smooth gradient. The aim is to seal in
the dry topsoil and reduce rainfall infiltration. (e).
If the topsoil is to be stored for more than 3 months, a
quick germinating fescue/clover seed mix shall be sown
over the sides and top of the stockpile to stabilise the
surface and reduce the risk of erosion.
Once the stockpile has been completed the area shall be cordoned off with secure fencing to prevent any disturbance or contamination by other construction activities.
Figure 2: Dry Stockpiling Method
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3.8 Subsoil / Formation Level Preparation
3.8.1 It is likely that the subsoil / formation level will have been heavily compacted during the construction
period. Therefore, prior to spreading any topsoil (or additional subsoil), the subsoil/ formation level
shall be loosened to a depth of at least 500mm to break up any panning.
3.8.2 On larger, open areas a tractor drawn wing-tined subsoiler set at 600mm centres (or similar and
approved) shall be used.
3.8.3 Rips shall be preferably made at 90 degrees in 2 directions, and at 45 degrees to direction of slopes
on mounds from the toe of the mound.
Plate 1: Wing-tined subsoiler Plate 2: Tractor drawn subsoiler
3.8.4 For small and restricted access areas, a tracked excavator, fitted with a single tine ripper
attachment (ripper tooth) shall be used to loosen the subsoil.
Plate 3: 360 with Single Rigid Tine Attachment Plate 4: Single Rigid Tine working
3.8.5 Repeated passes may be needed to break up the subsoil sufficiently. This shall be largely
dependent on the strength of the soil and its resistance to cultivation at the time of the operation.
3.8.6 Any large stones and other debris larger than 75mm brought to the surface by this cultivation shall
be stone picked or raked and removed. The stones shall either be re-used on site or they shall be
removed off-site to a suitably licensed waste facility.
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3.9 Subsoil Respreading
3.9.1 Where additional subsoil is required, subsoil spreading shall be carried out using the approved site
subsoil or imported subsoil (where required).
3.9.2 A hydraulic excavator fitted with a toothed-bucket shall be used to load the subsoil from the
stockpile into a dump truck.
3.9.3 The dump truck shall transport the subsoil to the desired location and tip it in a line of heaps.
3.9.4 The subsoil shall be spread by a second tracked excavator working from the formation layer or a
temporary surface or adjacent hard standing.
3.9.5 The subsoil shall be spread in 200mm layers. Each layer shall be consolidated by tracking in, or
using the excavator bucket, or by trampling in (restricted areas only) as deemed appropriate.
3.9.6 The subsoil shall be graded to smooth flowing contours.
3.9.7 The minimum subsoil depths after firming for each of the proposed landscape environments (except
tree pits – see section 4) shall be as follows (tolerance +/- 10%):
Landscape Environment Min. Recommended Thickness of Subsoil (mm)*
Woodland Core Mix 700
Woodland Edge / Shrub Mix 300
Woodland Field Layer Mix 300
Amenity / Ornamental Planting 300
Hedge 300
Amenity Grass 150
Species-rich Grassland 150
Temporary Grassland 150
Marginal / Aquatic Planting --
* Full subsoil thickness may include in-situ subsoil plus additional ‘top up’ of subsoil to make up recommended depth
3.10 Topsoil Respreading
3.10.1 Topsoiling shall be carried out using the approved site topsoil or imported topsoil (where required).
3.10.2 A hydraulic excavator fitted with a toothed-bucket shall be used to load the topsoil from the
stockpile into a dump truck.
3.10.3 The dump truck shall transport the topsoil to the desired location and tip it in a line of heaps.
3.10.4 The topsoil shall be spread by a second tracked excavator working from the subsoil layer or a
temporary surface or adjacent hard standing.
3.10.5 The topsoil shall be spread in one layer. Each layer shall be consolidated by tracking in, or using
the excavator bucket, or by trampling in (restricted areas only) as deemed appropriate.
3.10.6 The topsoil shall be graded to smooth flowing contours with falls for adequate drainage and
removing any minor ridges or hollows.
3.10.7 The topsoil depths after firming for each of the proposed landscape environments (except tree pits
– see section 4) shall be as follows (tolerance +/- 10%):
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Landscape Environment Depth of Topsoil (mm)
Woodland Core Mix 300
Woodland Edge / Shrub Mix 300
Woodland Field Layer Mix 300
Amenity / Ornamental Planting 300
Hedge 300
Amenity Grass 150*
Species-rich Grassland 150*
Temporary Grassland 150*
Marginal / Aquatic Planting 300
* Or up to 300mm topsoil if there is surplus available
3.11 Topsoil Cultivation
3.11.1 After respreading topsoil (site-won and imported), the soil profile shall be ripped at 300mm centres
to a minimum depth of 300mm (grass areas) or 600mm (shrub beds, hedges) to decompact the
soils and key-in the topsoil and subsoil layers.
3.11.2 On larger, open areas a tractor drawn wing-tined subsoiler set at 600mm centres (or similar and
approved) shall be used.
3.11.3 For small and restricted access areas, a tracked excavator, fitted with a single tine ripper
attachment (ripper tooth) shall be used to loosen the soil profile.
3.11.4 Any large, compacted lumps shall be broken down further by appropriate cultivation to produce a
fine tilth suitable for planting (
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Plate 5: Excavator with Landscape Rake Attachment
Plate 6: Landscape Rake Attachment
3.12 Soil Ameliorants
3.12.1 Where site-won topsoil is used, the following ameliorants shall be applied where appropriate. Any
necessary soil ameliorants for imported topsoil shall be indicated in the analysis report(s) as
required by the soft landscape specification for each phase.
3.12.1 For site-won topsoil that is to be used for tree and shrub planting, a compound, slow release
fertiliser shall be applied and incorporated (e.g. Everris Enmag CRF
(11%N:22%P2O5:9%K2O:6%MgO at a rate of 70 g/m2) or similar and approved).
3.12.2 For amenity grass establishment, a pre-seeding grass fertiliser shall be applied and incorporated
into the site-won topsoil prior to seeding or turfing (e.g. Everris Sportsmaster Pre-seeder
(8%N:12%P2O5:8%K2O+3%MgO at a rate of 35 g/m2) or similar and approved).
3.12.3 No fertiliser shall be applied to topsoil used within areas of proposed species-rich grassland
establishment.
4. TREE PIT CONSTRUCTION AND BACKFILLING
Tree pits shall be constructed with reference to the Bradley Murphy Design Ltd tree pit detail drawings and
landscape specification for each development phase.
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5. SITE SOIL MONITORING
5.1 Site Soil Monitoring
5.1.1 The project site manager will inspect and control operations on site in accordance with this soil
resource plan.
5.1.2 The project site manager shall carry out site inspections and liaise with the landscape architect/ soil
scientist/ site engineer/ contractor as necessary during the earthworks and landscape phases.
5.1.3 If required by the project site manager, a soil scientist shall attend a pre-start meeting prior to
commencement of the soil stripping operations to communicate the strategy to all contractors.
5.1.4 The following operations in particular shall be inspected and monitored by the project site manager:
• Soil stripping and storage
• Importation and storage of soils;
• Subsoil / formation layer preparation
• Tree pit construction
• Topsoil placement and preparation
• Topsoil amelioration
• Planting and plant establishment.
5.1.5 If required by the project site manager, a short report shall be produced after each site inspection to
ensure that work is satisfactory and compliant with the soil resource plan and specification. At the end
of the contract and if required by the project site manager, a completion report shall be issued to
confirm that a suitable soil quality has been achieved and that the soils are fit for the landscape
scheme.
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Report Qualifications
This Soil Resource Plan considers the re-use of the site won topsoil and subsoil for the soft landscape
scheme for Key Phase 1, Alconbury Weald, Cambridgeshire. It shall not therefore be relied on for
alternative end-uses or for other schemes. This report has been prepared solely for the benefit of our client
Urban & Civic Limited. No warranty is provided to any third party and no responsibility or liability shall be
accepted for any loss or damage in the event that this report is relied upon by a third party or is used in
circumstances for which it was not originally intended.