BCU Geotech Limited

BURTON SITE INVESTIGATION REPORT

CONTENTS

1. INTRODUCTION

2. THE SITE

3. PUBLISHED GEOLOGY

4. GROUND CONDITIONS

5. ASSESSMENT OF POTENTIAL CONTAMINATION AND SOIL GASES

6. ASSESSMENT OF MINING AND QUARRYING

7. ASSESSMENT OF EARTHWORKS

8. FOUNDATION RECOMMENDATIONS

9. EXCAVATIONS AND DEWATERING

10. ASSESSMENT OF SOAKAWAY DRAINAGE

11. ROAD PAVEMENTS

12. SUMMARY

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1. INTRODUCTION
The Client proposes to develop a site at Burton, for commercial purposes. The site is
currently unoccupied and forms part of a larger site awaiting development. Development
proposals for the site include construction of a warehouse facility, with office facilities, dock
leveller loading bays, a large car parking area and limited managed landscaped areas.

A previous consultant carried out ground investigations at the site in 1999, 2001 and 2005.
The factual data from these investigations have been made available and are presented in
this report.

BCU Geotech Limited was commissioned to undertake a site investigation to identify

potential constraints to the development relating to ground conditions. This report presents
the information obtained from a desk study and ground investigations. Geotechnical and
environmental assessments are presented, together with recommendations for
foundations, road pavement design and general construction works.

2. THE SITE

2.1 Location
A plan of the site is shown on Figure 1.
The A38 forms the western site boundary, beyond which are open fields. To the north of the
site, is an estate road, known as Callister Way, beyond the road is a brewery. To the east
and southeast is the Trent and Mersey Canal.

2.2 Site Description

This site description is based on observations made during the ground investigation on 23
October 2007.

The site is an approximately rectangular-shaped plot of land with an area of around 10.58
ha. The site falls down approximately 2 m from the north-western boundary to the south-
eastern boundary. The site is divided into two sections by a northeast to southwest trending
drainage ditch. A site access road is present in the north-eastern section of the site along
the side of the drainage ditch. The road has been blocked by steel barriers and concrete
manhole rings. Services are present beneath the road and appear to extend across the site
and adjacent to the drainage ditch.

The site is generally covered by grass and rough vegetation. The southern-most section of
the site is covered by trees and dense vegetation.

2.3 Site History

The site history has been researched with reference to old editions of the County Series and
National Grid Ordnance Survey Plans obtained from the British Library, London. Extracts
from a selection of these plans are presented in Appendix I. The plans indicate the following
development has taken place on and around the site.

The map, dated 1902, shows the site be used as fields with small farm buildings indicated in
the western and eastern sections of the site. A brewery is indicated to the north. By 1924,

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the small building in the western section of the site had been demolished. To the west and
northwest of the site, old marl pits are shown. The site and surrounding area are shown to
have remained relatively unchanged by 1950. The A38 road, which forms the western
boundary of the site, had been constructed by 1972, although the site and much of the
surrounding area remained unchanged. By 1991, the small building in the eastern section of
the site had been demolished. Since this time the access road and drainage ditch have been
constructed and a commercial development has taken place to the north of the site and to
the southeast of the canal.

2.4 Desk Study Enquiries

Enquiries were made to the Envirocheck Environmental Database and the Environment
Agency Web Site regarding the site and surrounding area. Information obtained from these
enquiries is presented in Appendix II and summarised below.

The Envirocheck Environmental Database indicates that there are no contaminated land
register entries and notices, hazardous substance consents, radioactive consents or water
industry referrals within a 500 m radius of the site.

There are two recorded integrated pollution control authorisations within a 500 m radius of
the site. These relate to the brewery to the north of the site. There is one recorded pollution
incident to controlled waters within a 500 m radius of the site. This is recorded 400 m to the
east of the site and related to a blocked sewer.

A brook, recorded 49 m to the southeast of the site is described as River Quality C – fairly
good.

There are no current landfill sites within a 500 m radius of the site. There are three former
landfill sites within a 500 m radius of the site. All of these lie the other side of the A38.
Former landfill sites extend from approximately 325 m to the north/northwest of the site. A
former landfill site extends from approximately 500 m from the northern site boundary.
Information from the Envirocheck Environmental Database and the Environment Agency
website indicates that one of them accepted inert wastes (such as brick, tiles, glass, tiles and
soils) between 1966 and 1982. Another is recorded to have accepted industrial wastes
(possibly from the brewery) and a third accepted inert wastes and industrial wastes
between 1920 and 1984.

The nearest recorded current commercial activity is a car component manufacturer 52 m to

the north of the site. Other commercial activities within the vicinity of the site include
distribution services, an insulation company and a seal and joint manufacturers. There are
no recorded fuel sites within a 500 m radius of the site.

The Envirocheck Environmental Database identifies the majority of the site to lie on a minor
aquifer of high leaching potential with the north-western section of the site indicated to lie
on non-aquifer strata. The Envirocheck Environmental Database and the Environment
Agency search shows that the site is within an outer groundwater Source Protection Zone
although the source protection zone relates to the Sherwood Sandstone strata at depth
beneath the site. There are over 100 recorded abstraction licences within a 1 km radius of

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the site. Most of these relate to the breweries to the north of the site where groundwater is
abstracted for process water, cooling and irrigation purposes. There are six recorded active
discharge consents within a 250 m radius of the site. The nearest of these lies 300 m to the
west of the site, where sewage discharges are discharged to a stream. The central section of
the site lies within an indicative flood plain as defined by the Agency.

Based on information within BGS Technical Report WP/95/2, the site lies within an area
where there is a “low-moderate” radon potential, defined as having less than 1% of
dwellings exceeding the action level.

3. PUBLISHED GEOLOGY
Reference to the 1:50,000 solid and drift geology map of Burton Upon Trent (Sheet 140),
published by the British Geological Survey indicates the site to be underlain by superficial
River Terrace Deposits. The underlying solid strata comprise Triassic Mercia Mudstone, with
Triassic Sherwood Sandstone at depth below the Mercia Mudstone.

4. GROUND CONDITIONS

4.1 Ground Investigation

Factual information from the ground investigations undertaken by A Consultant for the
Environment Limited at the site are presented in Appendix III. Details of the rationale for the
BCU Geotech Limited ground investigation and laboratory testing, together with exploratory
hole logs, monitoring, in situ and laboratory test results, are presented in the Appendix. The
investigations have identified the following, below the site.

4.2 Buried Foundations and Services

No buried foundations and services were encountered during the ground investigation.
Buried services exist beneath the central section of the site, beneath the access road and
adjacent to the drainage ditch.

4.3 Strata Encountered

Topsoil/Made Ground
A thickness of topsoil/Made Ground is present across the site to depths of up to 1.1 m but
generally less than 0.4 m. The topsoil at the site generally comprise stiff, brown, sandy, gravelly,
clays with roots locally these deposits locally contain rare brick and concrete fragments.
Alluvium
Beneath the topsoil a thickness of Alluvium is present to depths of up to 2.4 m, but generally
less that 1.5 m in the northern part of the site, less than 1.5 m in the central section of the site
and less than 1 m, and locally absent, in the southern and southwestern sections of the site. The
Alluvial deposits at the site typically comprise firm to stiff, red and orange brown, sandy, clays.
Towards the base of the alluvial deposits a thin, discontinuous layer of organic/peaty clay is
present across parts of the site. The peat layers, where present, are typically less than 0.3 m
thick.
River Terrace Deposits
River Terrace Deposits are present beneath the alluvial deposits to depths of up to 7.7 m. The
River Terrace Deposits beneath the site generally comprise medium dense, sandy gravels and
gravelly sands.
Mercia Mudstone

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Mercia Mudstone strata are present beneath the River Terrace Deposits to depths greater than
17.5 m. The shallow Mercia Mudstone strata comprise stiff, red brown, sandy, clays with
mudstone and siltstone lithorelics. With depth these deposits become weak to moderately weak
mudstones and sandstones

4.4 Groundwater
During the BCU Geotech Limited investigation, groundwater seepages/inflows have been
recorded across the site within the River Terrace Deposits at depths of between 1.35 m and 2.9
m below current site levels (between 44.1 m to 45.7 m AOD). Excavations below the
groundwater encountered ‘running sand’ conditions and the pits collapsed.

Groundwater monitoring at the site indicates that groundwater exists at depths of between 1.65
m and 2.97 m below current site levels (between 44.75 m to 45.45 m AOD). The groundwater
conditions are based on observations made at the time of the fieldwork. It should be noted
that groundwater levels may vary due to seasonal and other effects.

4.5 Soil Gases

A previous consultant undertook gas monitoring at the site in 1999. The gas monitoring data
indicates that no methane has been recorded at the site and that locally carbon dioxide has
been measured with maximum recorded concentrations of 4.4 %. No significant flow rates
were recorded.

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5. ASSESSMENT OF POTENTIAL CONTAMINATION AND SOIL GASES

5.1 Assessment Criteria

Assessment of potential contamination and soil gases has been undertaken using a risk
assessment based approach, as recommended within the Environmental Protection Act
(1990), CLEA Model (2002), BS 10175 (2001) and CIRIA C552 (2001). This approach considers
the likely source of contamination, given the history and location of the site, and the
possible migration pathways by which these potentially hazardous substances may reach
likely receptors, such as end users of the site, controlled waters or the wider environment,
in the context of the proposed development.

Part IIA of the Environmental Protection Act (1990) states that “Contaminated Land is any
land which appears to the local authority in whose area it is situated to be in such a
condition, by reason of substances in, on or under the land, that –
(a) significant harm is being caused or there is a significant possibility of such harm being
caused; or
(b) pollution of controlled waters is being, or is likely to be caused;”

All risk assessments carried out as part of this investigation have been carried out with
respect to the definition of “contaminated land” within Part IIA of the Environmental
Protection Act (1990) and have considered the site both before and on completion of the
development.
Analytical laboratory analyses have been undertaken to confirm the presence, of potentially
hazardous substances identified by the desk study researches, site reconnaissance and
following inspection of the ground conditions revealed during the investigation. The
rationale for BCU Geotech Limited sampling and testing is set out in an Appendix (not
included here).

The conceptual site model used in this assessment is presented in the Table.

5.2 Potential Sources of Contamination

The site was previously used as fields and has remained relatively undeveloped until the
recent construction of an access road and a drainage ditch. Ground conditions at the site
comprise a thickness of topsoil/Made Ground over alluvial deposits and River Terrace
Deposits, with Mercia Mudstone strata present at depth beneath the site. The Made
Ground at the site generally comprises re-worked topsoil and natural strata with rare brick.

No visual or olfactory evidence of contamination has been identified during the ground
investigation.

Reference to Table 1 indicates that, within the soils, priority contaminants are below the
generic assessment criteria.

Reference to Table 2 indicates that within the soils, the priority contaminants can be
considered to be relatively immobile. However, locally water leachable copper exceeds the
relevant Environmental Quality Standard (EQS).

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Potential contaminants are generally present within the groundwater beneath the site at
concentrations below the relevant environmental quality guidelines. However, elevated
levels of selenium are present within the groundwater beneath the eastern-most section of
the site.

No significant quantities of putrescible material have been identified within the Made
ground at the site and the site is not within an area where precautions against the ingress of
radon gas are required in new dwellings.

Alluvial soils are present beneath the site and include localised horizons of organic and
peaty materials. Substantial peat deposits are capable of producing methane, although only
in negligible volumes and at very low flow rates. Very small volumes of peat have been
recorded at the site within thin, discontinuous horizons. It is not possible for such small
volumes of organic material to generate significant emissions at the surface. Research data
within CIRIA Report 149 (1995) shows that, in the U.K, development has occurred on former
wetland areas without any apparent incident or problem from methane and associated
gases. The alluvial soils beneath the site, are therefore, considered not to be a potential
source of significant soil gas generation.

Three former landfill sites are recorded within a 500 m radius of the site, the nearest of
these being approximately 325 m to the north/northwest of the site. Based on the materials
deposited at the former landfill sites, they are considered as a potential source of soil gas
generation.

5.3 Pollution Linkages – Solids and Liquids

Based on the Conceptual Site Model, consideration is given below to identified pollution
linkages and a risk evaluation is undertaken of each possible source-pathway-receptor
linkage that may occur at the site. The risk evaluation considers the potential consequences
and probability of occurrence in accordance with CIRIA C552 (2001). Where risks are
identified as “negligible”, then by implication such risks are within normally accepted levels
for the proposed development, and the further reduction of such risks by remediation
works is considered unnecessary. Where risks are identified that are “low” as defined in
CIRIA C552 (2001), or worse, then consideration is given to the management of the
identified risks, with appropriate recommended actions that may include engineering
solutions /remediation works as described in the following sections.

5.3.1 Human Health

Excavated soils should be kept damp whilst exposed in dry, windy weather to minimise the
potential for dust affecting neighbouring properties and the general public.

5.3.2 Buried Structures and Services

In view of the low soluble sulphate content and near neutral soil conditions, there are no
special precautions required for the protection of good quality buried foundation concrete.
Based on guidance within BRE Special Digest 1 (2005), the specified DC Class of concrete for
buried structures and foundations should be suitable for an ACEC site classification of AC-1.

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There is no evidence of high concentrations of harmful substances within the shallow soils
that would necessitate the special protection for buried services. It is considered that
normal plastic construction materials may be used.

5.3.3 Controlled Waters

Reference to Table 2 indicates that within the soils, the priority contaminants can generally
be considered to be immobile. However, locally water leachable copper exceeds the
relevant Environmental Quality Standard (EQS). It should be noted that these
concentrations have been recorded within the shallow topsoil/Made Ground and these
materials will be removed from site to enable construction thus no source of leachable
copper will remain on site. Notwithstanding this assessment, should these materials be
retained on site, metals are generally of low solubility at typical soil pH conditions. The
proposed development also incorporates large areas of building and hardstanding that will
reduce the availability of water for leaching after construction. Downward migration of
substances will be also be restricted by the shallow clayey alluvial strata beneath the site.

The above assessment is confirmed by the absence of significant copper concentrations

within the groundwater beneath the site.

Reference to Table 3 indicates that potential contaminants are generally present within the
groundwater beneath the site at concentrations below the relevant environmental quality
guidelines.

However, elevated levels of selenium are present within the groundwater beneath the
eastern-most section of the site, with the highest concentrations recorded on the eastern-
most site boundary. No potential source of selenium has been identified with the site’s
previous usage and no significant concentration of selenium has been identified within the
soils beneath the site. Due to the direction of groundwater flow beneath the site and due to
the area where selenium has been recorded it is considered likely that the selenium has
migrated on to the site from an off-site source. It is therefore considered that there is a
negligible risk to controlled waters associated with the site in its current condition and this
will not change following development.

5.4 Pollution Linkages – Gases

Based on the Conceptual Site Model, consideration is given below to identified pollution
linkages and a risk evaluation is undertaken of each possible source-pathway-receptor
linkage that may occur at the site. Where risks are identified as “negligible”, then by
implication such risks are within normally accepted levels for the proposed development,
and the further reduction of such risks by remediation works is considered unnecessary.
Where risks are identified that are “low” as defined in CIRIA C552 (2001), or worse, then
consideration is given to the management of the identified risks, with appropriate
recommended actions that may include engineering solutions with remediation works or
soil gas protection and control systems as described below. Reference is made to guidance
published in BRE BR211 (1999) as referenced by the Building Regulations, to relevant
assessment criteria published in Waste Management Papers 26A (1993) and 27 (1991),
together with subsequent CIRIA documents, as listed in the References.

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Three former landfill sites are recorded within a 500 m radius of the site. The nearest of
these is approximately 325 m to the north/northwest of the site. Due to the age and nature
of the wastes accepted at these former landfill sites it is considered that that the potential
for significant landfill gas generation at these sites will be low. In addition, due to the local
topography, and due to the presence of low permeability Mercia Mudstone strata and the
absence of River Terrace Deposits between the site and the former landfill sites, the
potential for significant landfill gas migration towards the site will be negligible.

Gas monitoring undertaken at the site has not recorded any methane beneath the site and
no significant flow rates have been recorded. Locally, carbon dioxide has been recorded
with maximum concentrations of 4.8 %. It is therefore considered that the proposed
development should not be constrained by issues relating to soil gases and soil gas
precautions should not be required within the proposed structure at this site.

5.5 Recommended Remedial Works

It is considered that no soil or groundwater remedial works will be required at this site to
permit development.

5.6 Potential Liabilities

On the basis of the above, it is considered that ownership and development of the site does
not present a significant risk of harm to end users or the wider environment and retention
of the materials presently at the site should not be associated with any liability following
completion of the development.

5.7 Disposal of Materials

There is no requirement to remove materials from site to permit development. Therefore,
excavated materials should be retained and reused on site where possible. If inorganic
natural materials (River Terrace Deposits) are excess to requirements and cannot be
accommodated on site, they should be acceptable at a landfill site that is permitted to
accept “inert” waste or at an exempt site under the Waste Management Regulations.

Any surplus Made Ground materials and organic natural materials (topsoil and alluvial soils)
will require to be taken to a site that accepts “non-hazardous” waste, as it will not be
accepted as “inert” waste due to total organic carbon concentrations. The tarmac surfacing
from the former access road should be taken to a recycling facility.

Landfill tax would be payable on any materials removed to a licensed landfill.

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6. ASSESSMENT OF MINING AND QUARRYING
The site is not located within an area of recorded past mining or quarrying. Therefore,
associated issues of ground stability are not applicable to the development.

7. ASSESSMENT OF EARTHWORKS
It is understood that the finished floor level for the proposed structure is 47.52 m AOD and that
to achieve the proposed finished floor level, site levels will be raised beneath the building
footprint. There will also be a requirement to cut materials from the northern part of the site.

The results of the geotechnical laboratory testing undertaken on the materials in the
northern section of the site indicate that it may be possible to re-use these materials as
earthworks fill in an as-dug condition. However, it should be noted that, due to the
relatively high silt content, these materials are very sensitive to moisture content change
and trafficking. If exposed to inclement weather, these soils can rapidly soften and become
unsuitable as earthworks material. The shallow materials from the northern section of the
site are considered to fall into “Class 2C”, materials as defined in the Specification for
Highway Works 1994.

Due to proposed finished levels, there may be a requirement to import materials. It should be
noted that, if materials used to raise site levels are imported from another site, these materials
may be classified as a waste. If the materials are classified as a waste, there will be a
requirement to obtain a waste management license exemption for the site. Prior to importing
materials to site, earthworks testing should be carried out on the materials to confirm the
suitability for use as an earthworks material and the suitability for use beneath the building.
Analytical testing will also be required to confirm that the materials meet the requirement of
the waste management license exemption.

8. FOUNDATION RECOMMENDATIONS

8.1 Foundations
It is understood that the finished floor level for the proposed structure is 47.52 m AOD and that
the minimum foundation level will be approximately 46.47 m AOD. Dock-levellers are proposed
along the southwestern corner of the structure and, in this area, a minimum foundation level of
45.42 m AOD will be required.

It is considered that it should be possible to support the proposed structure on conventional pad
and strip foundations taken into the shallow River Terrace Deposits.
The recommended parameters for the foundation design are as follows:
Foundation Strata : Medium dense sands and gravels - River Terrace Deposits
Foundation Depth : Minimum foundation depth of 0.9 m, deepened, through the alluvial and
peat deposits, as required. Foundations should be taken no more than 300 mm into the River
Terrace Deposits to avoid groundwater ingresses and excavation instability
Nett Allowable Bearing Pressure: 150 kN/m2

It is considered that total settlement of foundations designed on the above basis should be
less than 25 mm.

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In view of the low soluble sulphate content and near neutral soil conditions, there are no
special precautions required for the protection of good quality buried foundation concrete.
Based on guidance within BRE Special Digest 1 (2005), the specified DC Class of concrete for
buried structures and foundations should be suitable for an ACEC site classification of AC-1.

8.2 Floor Slabs

It is understood that to achieve the proposed finished floor level, site levels will be raised
beneath the building footprint. Ground bearing floor slabs will be possible for this site, providing
that any fill materials are placed and compacted in a controlled matter. The design criteria for
the floor slab will depend on the nature of the materials and the method of placement and
compaction that is used.

A drainage ditch runs beneath the proposed structure and there will be a requirement to divert
the ditch away from the building and backfill the existing ditch prior to construction. The ditch
should be backfilled using suitable granular materials and flows into the granular materials
diverted to the new ditch.

8.3 General Construction Advice

All formations should be cleaned, and subsequently inspected by a suitably qualified
engineer prior to placing concrete. Should any soft, compressible or otherwise unsuitable
materials be encountered they should be removed and replaced by blinding concrete.
Foundation concrete, or alternatively, a blinding layer of concrete, should be placed
immediately after excavation and inspection in order to protect the formation against
softening and disturbance.

Generally, all formations should be placed wholly within the same material type, unless
specific geotechnical inspection and assessment have been undertaken. Care should be
taken to ensure that any field drains encountered are carefully and satisfactorily blocked to
prevent water seeping through the drains and into any excavations.

The locations of any trial pits undertaken as part of this investigation should be accurately
surveyed in order that their precise locations are known and that appropriate precautions
can be taken when building over or near to these locations.

9. EXCAVATIONS AND DEWATERING

Conventional plant is considered to be appropriate for excavation works at the site, with an
allowance for hydraulic breakers to break out any concrete in the area of the access road.
Excavations above groundwater are expected to remain stable in the short term, although
some spalling should be anticipated if the excavations are left open for extended periods of
time, and particularly during inclement weather. Support should be provided, or the sides
battered back, in any excavation in excess of 1.2 m requiring man-entry.

Groundwater inflows should be anticipated at depths of between 1.35 m and 2.9 m below
current site levels. Excavations below the groundwater are unlikely to remain stable, and
‘running sand’ conditions may be encountered. If deep excavations are required, the use of
temporary sheet piles may be required to support short excavations and restrict
groundwater ingress. If long excavations are proposed, well point dewatering may be used
as an alternative to sheet piles.
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Well point dewatering will lower groundwater levels and improve excavation stability. It
should be possible to discharge the abstracted water to the brook to the south of the site,
but it is likely to be necessary to pass the water through a series of interceptors/traps to
ensure that water is free of fines before disposal to the brook.

10. ASSESSMENT OF SOAKAWAY DRAINAGE

The use of soakaway drainage requires the consent of the Environment Agency. The
Envirocheck Environmental Database identifies the majority of the site to lie on a minor
aquifer of high leaching potential. However, the Envirocheck Environmental Database and
the Environment Agency search shows that the site is within an outer groundwater Source
Protection Zone and there are over 100 recorded abstraction licences within a 1 km radius
of the site. Most of these relate to the breweries to the north of the site where groundwater
is abstracted for process water, cooling and irrigation purposes.

Based on their published policy, the Environment Agency is unlikely to object to the use of
soakaways at the site for roof and hardstanding drainage, although there may be a
requirement to provide an interceptor drain in car parking areas prior to discharge to
soakaways/swales or the diverted ditch.

Percolation testing undertaken in the north eastern section of the site indicates the shallow,
River Terrace Deposits strata to have soil infiltration rates (as defined in BRE 365, 1991) of
between 1.6 x10-5 m/s and 4.3 x10-5 m/s. However, on the basis that the soil infiltration rates
have been estimated from data based on filling the test pit only once, it is recommended that
the design infiltration rate be reduced. It is therefore considered that soakaway drainage within
the River Terrace Deposits strata at the site be designed on the basis of a maximum soil
infiltration rate of 1×10-5 m/sec. It should be noted that any proposed drainage layout should
allow at least 5 m between soakaways and buildings. Soakaways should not be constructed
in ground where the water table reaches the bottom of the soakaway drainage system.

11. ROAD PAVEMENTS

Based on an examination of the soils present at the site, and the guidance published in TRRL
LR1132, it is considered that an equilibrium design CBR of 2-5% may be used at this site.

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12. SUMMARY
It is proposed to develop a site at Burton, for commercial purposes. The site
is currently unoccupied and forms part of a larger site awaiting development. Ground
conditions at the site comprise a thickness of topsoil/Made Ground over Alluvium and River
Terrace Deposits, with Mercia Mudstone strata present at depth beneath the site.
Groundwater seepages/inflows have been recorded across the site within the River Terrace
Deposits at depths of between 1.35 m and 2.9 m below current site levels (between 44.1 m to
45.7 m AOD). Excavations below the groundwater encountered ‘running sand’ conditions and
the excavations collapsed.

It is considered that the proposed development will not be constrained by issues relating to
contaminated land or soil gases and no that remedial works will be required to permit
development.

It is understood that to achieve the proposed finished floor level, site levels will be raised
beneath the building footprint. There will also be a requirement to cut materials from the
northern part of the site. It may be possible to re-use the materials from the northern part of
the site as earthworks fill in an as dug condition. However, due to the relatively high silt
content, these materials are very sensitive to moisture content change and trafficking and, if
exposed to inclement weather, these soils can rapidly soften and become unsuitable as
earthworks material.

There may be a requirement to import materials. It should be noted that, if materials used to
raise site levels are imported from another site, these materials may be classified as a waste. If
the materials are classified as a waste, there will be a requirement to obtain a waste
management license exemption for the site.

It is considered that it should be possible to support the proposed structure on conventional pad
and strip foundations taken into the shallow River Terrace Deposits above the groundwater.
Ground bearing floor slabs will be possible for this site, provided that any fill materials are
placed and compacted in a controlled matter.

The use of soakaway drainage should be possible for this site, within the River Terrace Deposits
strata, and can be designed using a maximum soil infiltration rate of 1×10-5 m/sec.

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TABLES

TABLE 1

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TABLE 2

FIGURES

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HISTORICAL MAP

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APPENDIX II
TRIAL PIT LOCATION PLAN

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FIGURE 1

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APPENDIX III – FACTUAL INFORMATION FROM PREVIOUS SITE INVESTIGATIONS

Information from previous ground investigations, carried out by A Consultant for the Environment Limited, was made available. This Appendix
presents a selection of the information provided and includes exploratory hole location plans, exploratory hole records, soil and groundwater
analytical test results, soil gas monitoring records and geotechnical laboratory test results.

APPENDIX IV

APPENDIX IV – GROUND INVESTIGATION

The site operations were carried out between 23 October and 19 November 2007 under the
supervision of a geotechnical engineer from BCU Geotech Limited. The rationale for the
design of the investigation is presented in Table IV-1.
An exploratory hole location plan is presented as Figure V-1.

Trial Pits
Twenty trial pits, denoted as TP105-TP113, TP117-121, TP126, TP130 and TP131, were excavated by a JCB 8060 tracked excavator between 23
and 26 October. The trial pit records from the investigation are presented in this Appendix and these records include the descriptions and
depths of the strata encountered, together with sample depths, groundwater observations and other pertinent comments.

In Situ Soakaway Tests

In situ soakaway tests were performed in Trial Pits TP118, TP119 and TP120 generally in accordance with the requirements of BRE Digest 365
except that they were filled only once. Trial Pits were filled with ‘clean’ water and the fall in water level measured with time. The results of the
in situ testing are presented in this Appendix.

Boreholes
Three light cable percussion boreholes, denoted as BH101, BH102 and BH104, were sunk by Site Investigations Limited, between 24 and 25
October, to between 7 m and 7.5 m. On completion, water monitoring standpipes were installed in boreholes BH101 to BH105 to depths of
between 7 m and 7.5 m. Disturbed samples were taken for descriptive and geotechnical testing purposes. Standard Penetration Tests were
carried out at regular intervals to provide data on the in situ density of granular strata and an indication of strength within cohesive strata. The
borehole records from this investigation are presented in this Appendix. These records include the descriptions and depths of the strata
encountered, together with sample depths, groundwater observations and other pertinent comments.
BCU Geotech Ltd – Burton Site 25 | P a g e
Soil Samples
All samples for analytical testing were collected in appropriate containers, stored in cool boxes (where appropriate) and sent to the testing
laboratory overnight.

Groundwater Sampling
Water samples were taken, in accordance with NRA R&D Note 126, on 19 November from the
borehole standpipes. Details of the groundwater sampling and associated water levels measured are presented in this Appendix, together with
permeability calculations.

On site water quality testing was undertaken to determine the following parameters:
• pH
• Conductivity
• Redox Potential
• Temperature
• Dissolved Oxygen
The results of the water quality testing are presented in this Appendix.

BCU Geotech Ltd – Burton Site 26 | P a g e