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Ground Investigationat

Buccleuch Academy,Kettering

Factual and Interpretative Report

for

Willmott Dixon ConstructionLimited

Project Number : PC104350

October 2010Issuing office :

Head Office CoventryGeotechnics LimitedThe Geotechnical Centre203 Torrington AvenueTile HillCoventryCV4 9APT: 024 7669 4664F: 024 7669 [email protected]

North West Office

Geotechnics Limited

The Geotechnical Centre

Unit 1, Borders Industrial Park

River Lane, Saltney

Chester

CH4 8RJ

T: 01244 671 117

F: 01244 671 122

[email protected]

Scottish Office

Geotechnics Limited


Block 1, Unit 8

Duckburn Business Park

Dunblane

FK15 0EW

T: 01786 823 328

F:01786 823 345

[email protected]

South West Office

Geotechnics Limited


7 Pinbrook Units

Venny Bridge

Exeter

EX4 8JQ

T: 01392 463 110

F:01392 463 111

[email protected]

Geotechnics Limited, Registered in England No. 1757790 at The Geotechnical Centre, 203 Torrington Avenue, Tile Hill, Coventry CV4 9AP

Ground Investigationat

Factual and Interpretative Report

Buccleuch Academy, Kettering

forWillmott Dixon Construction Limited

Project No:

PC104350

October 2010

LIST OF CONTENTS

Page No

1.0 INTRODUCTION 1

2.0 OBJECT AND SCOPE OF THE INVESTIGATION 1

3.0 PRESENTATION 1

4.0 THE SITE 1

4.1 Location 1

4.2 Description 1

5.0 PROCEDURE 2

5.1 Commissioning 2

5.2 General 2

5.3 Boreholes 2

5.4 Drillholes 2

5.5 Trial Pits 3

5.6 Instrumentation and Monitoring 3

5.7 Soakaway Tests 3

5.8 In Situ Permeability Tests 4

5.9 Dynamic Cone Penetration Tests 4

6.0 LABORATORY TESTING 4

6.1 Geotechnical 4

6.2 Contamination 4

7.0 DESK STUDY 5

7.1 General 5

7.2 Geology 5

7.2.1 Published Information 6

7.2.2 Previous Investigation Data 7

7.3 Conceptual Site Model 8

7.4 Hydrology 8

7.5 Hydrogeology 8

7.6 Environmental Issues 9

7.7 Site History 9

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8.0 INTERPRETATION 9

8.1 Ground Conditions 9

8.1.1 Made Ground / Topsoil 10

8.1.2 Superficial Deposits 10

8.1.3 Great Oolite Limestone 10

8.1.4 Upper Estuarine Series 11

8.1.5 Lincolnshire Limestone Formation and Lower Estuarine Series 11

8.2 Groundwater 11

9.0 GEOTECHNICAL EVALUATION 11

9.1 Proposals 11

9.2 Foundation Design Principles 12

9.3 Foundation Solutions 12

9.4 Excavations & Groundwater 12

9.5 Slab Design 13

9.6 Earthworks 13

9.7 Buried Concrete 13

9.8 Pavement Design 14

9.9 Soakaway Design 14

10.0 ENVIRONMENTAL ASSESSMENT 15

10.1 Legal Framework 15

10.2 Proposed Site Use 15

10.3 Conceptual Model 16

10.3.1 Sources 16

10.3.2 Pathways - General 16

10.3.3 Receptors - General 17

10.3.4 Site Specifice Contamination Linkages 17

10.4 Soil Testing 17

10.4.1 Introduction 17

10.4.2 Soil Results Summary 18

10.5 Monitoring Results 19

10.5.1 Groundwater 19

10.5.2 Ground Gas 20

10.6 Risk Assessment 20

10.7 Conclusions and Recommendations 21

CO

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APPENDICES

APPENDIX 1 The Brief

APPENDIX 2 Site Location Plan

APPENDIX 3 Site Photographs

APPENDIX 4 Borehole Records

APPENDIX 5 Rotary Drillhole Records

APPENDIX 6 Trial Pit Records

APPENDIX 7 Exploratory Hole Location Plan

APPENDIX 8 Monitoring Results

APPENDIX 9 Soakaway Test Results

APPENDIX 10 In Situ Permeability Test Results

APPENDIX 11 DCP Test Results

APPENDIX 12 Laboratory Test Results - Geotechnical

APPENDIX 13 Laboratory Test Results - Contamination (Soil)

APPENDIX 14 Laboratory Test Results - Contamination (Groundwater)

APPENDIX 15 Sections

APPENDIX 16 Material Property Plots

APPENDIX 17 Existing Soakaway Inspection Report

APPENDIX 18 Investigation Techniques and General Notes

AP

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ICE

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Geotechnics Limited Buccleuch Academy, Kettering

The Geotechnical Centre, Factual and Interpretative Report, Project No PC104350, October 2010.

203 Torrington Avenue,

Tile Hill, Coventry.

CV4 9AP Page 1 of 22

1.0 INTRODUCTION

A geotechnical and geoenvironmental investigation

was undertaken by Geotechnics Ltd at the site of a

proposed school development at Weekley Glebe

Road, Kettering. The investigation was carried out

to the instructions of and on behalf of the Client,

Willmott Dixon Construction Limited. This report

describes the work undertaken and presents the

data obtained together with an evaluation of their

significance in relation to the proposed works.

This work supplements an investigation carried out

by Geotechnics Ltd on the existing school site

(PC093887, July 2009) and a preliminary

investigation on the present site (PC094085, Jan

2010).

2.0 OBJECT AND SCOPE OF

THE INVESTIGATION

The object of the investigation was to obtain

information on the ground and groundwater

conditions relating to the design of the proposed

works within the limitations posed by exploratory

hole numbers, locations, depths, methods adopted

and the scope of approved in situ and laboratory

testing. The Brief for the project is included in

Appendix 1. The investigation comprised boreholes,

drillholes and trial pits, in situ and laboratory testing

and reporting. A geotechnical and geoenvironmental

interpretation and evaluation of the data obtained

was also commissioned.

3.0 PRESENTATION

A description of the site and a summary of the

procedures followed during the investigation process

are presented in Sections 4 to 6. The factual data so

obtained are presented in Appendices 2 to 17 of this

report. The findings of desk studies previously

carried out for the school development, supplied by

the Client, are summarised and discussed in Section

7. An interpretation of the data obtained from the

investigation is presented in Section 8 and an

evaluation of its significance in relation to proposals

available at the time of preparation of this report in

Sections 9 and 10. The report is also presented in

electronic PDF format separately on disk.

Attention is drawn to the General Notes and

Investigation Procedures presented in Appendix 18

to aid an understanding of the procedures followed

and the context in which the report should be read.

4.0 THE SITE

4.1 Location

The site is located approximately 2km north east of

the centre of Kettering and about 1.5km south west

of Weekley Church, just to the north of Weekley

Glebe Road. The approximate Ordnance Survey

National Grid Reference for the site is SP 878 802

and an extract from the relevant 1:50,000 Scale O.S.

Map (Sheet No. 141) is included as Appendix 2.

4.2 Description

The main area of the site investigation under this

phase, comprises a grassed public open space

immediately east of the existing Montagu School.

The area includes football pitches and a cricket pitch

and measures approximately 160m by 180m. The

site sloped generally to the south east from

approximately 100m OD in the north west of the

area down to approximately 98m OD in the south

east of the area. In the south west corner, however,

the ground surface dipped towards the south west

down to 96m OD.

The existing school site to the west of this area

comprises the school buildings in the eastern part

and sports fields to the west. The buildings typically

consist of a variety of one and two storey brick

buildings surrounded by areas of hardstanding and

soft landscaping. The area of the buildings generally

slopes down towards the south west, with the

gradient generally increasing towards the south west,

from a height of approximately 101m AOD at the

north east corner of the area down to 92m AOD in

the south west corner.

Ground Investigation Factual and Interpretative Report

at

BUCCLEUCH ACADEMY, Project No: PC104350

KETTERING October 2010






The area of the sports fields is generally flat with a

gradient sloping down from 98.5m AOD in the

north east of the area, down to 91.0m AOD in the

south west, in a series of steps. A bank,

approximately 2m high, extends across the field from

east to west creating a level area for pitches and a

running track. The sports field area is separated

from the main school building area by a bank

approximately 1m high, leading down to the sports

field.

Photographs taken during the fieldwork of the main

area of the site where the investigation works were

carried out are presented in Appendix 3.

5.0 PROCEDURE

5.1 Commissioning

The work was awarded following submission of a

proposal for ground investigation of the site in

accordance with the Client’s requirements (see

Appendix 1). The scope of the work was revised

during the site works based on the ground

conditions encountered.

5.2 General

The procedures followed in this site investigation are

based on BS 5930 (1999) - Code of Practice for Site

Investigations and BS 10175 (2001) – Investigation of

Potentially Contaminated Sites. The soils and rocks

encountered have been described in accordance

with Amendment 1 to BS5930, dated December

2007 and BS EN ISO 14688-1 (2002) and BS EN ISO

14689-1 (2003). The Standard Penetration Tests

(SPT's) were carried out in accordance with BS EN

ISO 22476-3 (2005). The Borehole, Drillhole and

Trial Pit Records are included in Appendices 4 to 6

and their approximate positions are shown on the

Exploratory Hole Location Plan in Appendix 7.

The Exploratory Hole locations were selected by

Geotechnics Ltd to cover the area of the proposed

buildings but avoiding the existing football pitches.

The levels shown on the Exploratory Hole Records

were obtained using a Leica Smart Rover Global

Positioning System linked to a Smartnet Network

and are related to Ordnance Datum. The depths

quoted are in metres below ground level.

5.3 Boreholes

Five (5 No.), 150mm diameter boreholes (numbered

BH1, BH3 to BH6) were sunk by Cable Percussion

Tool techniques to depths varying between 1.40m

and 10.00m below ground level. The work was

carried out between the 23rd and 26th August 2010.

An inspection pit was excavated at each borehole

location using hand tools to a depth of 1.20m below

ground level to check for the presence of

underground services.

Representative disturbed (D and B) and undisturbed

(U100) samples of the soils encountered were

obtained at regular intervals and SPTs undertaken in

appropriate deposits, in order to allow inspection

and obtain a measure of the engineering properties

of the proved strata. In addition, environmental

samples (E) were recovered at the depths indicated

on the Borehole Records.

No groundwater was encountered during the drilling

operations. On completion, standpipes were

installed in Boreholes BH4 and BH6 (see Section

5.6). The other boreholes were backfilled with

grout on completion.

5.4 Drillholes

Two (2 No.) 130mm diameter drillholes (numbered

R01 to R02) were sunk utilising open hole, rock-

roller drilling techniques to depths of 19.00m and

9.70m below ground level, respectively. The work

was carried out on the 24th August 2010. An

inspection pit was excavated at each borehole

location using hand tools to a depth of 1.20m below

ground level to check for the presence of

underground services.

The drilling equipment on this particular contract

utilised air-mist as the flushing medium. The strata

descriptions are the Drilling Foreman's estimate

based on sediment and chipping returns in the

flushing medium. The rate of penetration is also

used as an indicator of the type of material being

drilled, particularly where there is loss of flush

returns. Definitive classification in terms of geology

or degree of disturbance is not usually possible from

these sources.






Groundwater observations are included on the

Drillhole Records where appropriate and any rise in

water level was recorded over 20 minutes whilst

drilling operations were suspended. On completion,

standpipes were installed in both boreholes (see

Section 5.6).

In addition, a single 130mm diameter drillhole

(numbered R03) was sunk utilising open hole and

rotary coring techniques to a depth of 9.00m below

ground level. The work was carried out on the 25th

August 2010. An inspection pit was excavated at the

borehole location using hand tools to a depth of

1.20m below ground level to check for the presence

of underground services.

The drilling equipment utilised air-mist as the flushing

medium. Where rock quality had improved

sufficiently, 92mm diameter rock coring commenced

at a depth of 3.00m below ground level. The

recovered rock cores were extruded horizontally in

plastic liners and placed into suitable core boxes.

Photographs of the individual core boxes are

included in Appendix 5.

On completion, a standpipe was installed in

Borehole R03 (see Section 5.6).

5.5 Trial Pits

Two (2 No.) Trial Pits (numbered TP5 and TP6)

were excavated to a depth of 1.00m below ground

level using a tracked mini-excavator. In addition five

(5 No.) trial pits (numbered TP1 to TP4 and TP7)

were excavated to depths of 1.00m to 1.40m below

ground level. The pits were excavated on the 24th

August 2010 and the work supervised on site by a

geotechnical engineer.

The profiles of strata or other features were

recorded as excavation proceeded and

measurements taken from ground level. Pits were

entered where safe to do so to allow in situ

measurement of strata conditions. Representative

samples were taken, where appropriate, for

laboratory examination and analysis and in addition,

Environmental samples (E) were recovered at the

depths indicated on the Trial Pit Records. At depths

in excess of 1.20m below ground level or in unstable

conditions, samples were taken directly from

excavated materials deposited at surface.

Groundwater observations and trench stability notes

are included on the Trial Pit Records.

5.6 Instrumentation and

Monitoring

Long term monitoring of the gas and groundwater

levels was made possible by the installation of

standpipes as follows:

Exploratory

Hole

Standpipe

Slotted pipe & Filter Zone

(m)

BH4 3.70 to 6.80

BH6 1.00 to 5.00

R01 6.00 to 19.00

R02 3.00 to 6.30

R03 3.00 to 9.00

Monitoring of the gas and groundwater levels at the

site commenced on 3rd September 2010 with a

further 5 No. visits on 10th September, 30th

September, 12th October, 26th October and 9th

November 2010. In addition to the standpipes

installed as part of this investigation, monitoring was

also undertaken in selected standpipes installed

during the previous investigation (PC093887) carried

out in May 2009 (see Section 7.2 below).

At each position a record of the groundwater level

was taken. On the 10th September 2010 where

water was recorded, samples were obtained

following a purging of 3 volumes of water in the

standpipe.

In addition to the groundwater levels, the following

parameters were measured and recorded in each

standpipe using a GA2000 Gas Analyser:-

• Concentrations (% Vol) of CH4, O2, CO2,

along with (% LEL) CH4, H2S , CO

• Flow Rate

• Differential Pressure

• Barometric Pressure

• Air Temperature

The results of the monitoring are presented in

Appendix 8.

5.7 Soakaway Tests

Two (2 No.) soakaway tests were carried out in

Drillholes R01 and R02 on the conclusion of the

drilling operations at depths of 19.00m and 9.70m

below ground level, respectively. The results of the

tests are presented in Appendix 9 and the findings

are discussed below in Section 9.9.






5.8 In situ Permeability Tests

Following completion of the fieldwork an in situ

rising head permeability test was undertaken in the

standpipe installed in Drillhole R02, in accordance

with BS5930 (1999) Clause 25.4. The permeability

has been estimated using the initial groundwater

level measured in the standpipe and the results are

presented in Appendix 10.

5.9 Dynamic Cone Penetration

Tests

Three (3 No.) Dynamic Cone Penetration (DCP)

Tests numbered CBR1 to CBR3 were carried out at

the locations marked on the Exploratory Hole

Location Plan (see Appendix 7). The tests were

commenced from Ground Level and were

performed to give an indication of CBR values at

shallow depths to aid pavement design. The test

comprises the measurement of increments of

penetration of a 60° cone driven into the ground

using an 8kg hammer falling a distance of 575mm.

The CBR is obtained from the relationship between

the CBR and the DCP readings defined in Interim

Advice Note 73/06 "Design Guidance for Road

Pavement Foundations" published by the Highways

Agency:-

Log10(CBR) = 2.48 – 1.057 x Log10(mm/blow).

The test results are presented in Appendix 11.

6.0 LABORATORY TESTING

6.1 Geotechnical

The laboratory testing schedule was formulated by

Geotechnics Ltd in order to relate to the proposed

development. The tests, where appropriate,

conform to BS 1377 - Methods of Test for Soils for Civil

Engineering Purposes (1990) and were carried out in

Geotechnics Limited's UKAS accredited Laboratory

(Testing No. 1365). Any descriptions, opinions and

interpretations are outside the scope of UKAS

accreditation.

The tests undertaken can be summarised as follows:-

BS 1377 (1990)

Test No. Test Description

Part 2

3.2 17 No. Moisture Content

Determination

4.3 & 5.3 9 No. Liquid and Plastic Limit

Determination

9.2 & 9.3 6 No. Mechanical Analysis - Sieving

9.4 6 No. Mechanical Analysis -

Sedimentation

Part 4

3.3 4 No. Dry Density/Moisture Content

relationship determination.

Compaction Test - British

Standard (2.5 kg Rammer)

7 4 No. California Bearing Ratio (CBR)

Measurement

- recompacted

Part 5

3 3 No. One-Dimensional

Consolidation

Properties Determination.

Consolidation Test

Part 7

9 6 No. Shear Strength Measurement -

100mm diameter (Single Stage)

Quick Undrained Triaxial

Compression Test

The following testing was carried out at the

laboratories of Derwent Environmental Testing

Services (DETs):-

BRE Special Digest 1 Suite (Soil)

7 No. Suites comprising:-

Soluble Sulphate

Acid Soluble Sulphate

Total Sulphur

pH

The results of these tests are presented in Appendix

12.

6.2 Contamination

Selected samples of soil and groundwater were

tested in at the laboratories of Derwent

Environmental Testing Services (DETs) for a number

of determinands in order to check on potential site

contamination. The determinands were selected by

Geotechnics Limited.

Soil

Soil samples were tested for the following

determinands:-






Arsenic

Cadmium

Total Chromium

Copper

Lead

Manganese

Mercury

Nickel

Selenium

Zinc

Vanadium

Organic Matter

Total Organic Carbon

PH

EPH (C5 – C10)

EPH (C10 – C40)

Phenol (Monohydric)

In addition provision was made for additional

dependant option analysis for:

Hexavalent Chromium (if Total > 100 mg/kg)

Speciated Hydrocarbons (if EPH >250 mg/kg)

Speciated PAH (IF PAH > 50 mg/kg)

Asbestos if fibrous or suspect materials were located

on site.

The results are presented in Appendix 13.

Groundwater

Groundwater samples taken from the standpipes

installed during this and the previous investigations

were tested for the following determinands:-

Arsenic

Cadmium

Chromium

Copper

Lead

Mercury

Nickel

Vanadium

Zinc

pH

Electrical Conductivity

Sulphate

Sulphide

Total Dissolved Solids

Phenol

Total Organic Carbon

Total Polyaromatic Hydrocarbons

Total Petroleum Hydrocarbons

The results are presented in Appendix 14.

7.0 DESK STUDY

7.1 General

A number of existing reports on studies carried out

on or adjacent to the site have been supplied by the

Client and comprise:-

(1) "Northampton Academies, Kettering" Geo-

Environmental Site Fact Sheet, Mott

MacDonald Limited, Report

258960/ENV/01/A, April 2009.

(2) "The Kettering Buccleuch Academy –

Montagu Site" Phase 1 Preliminary Risk

Assessment, Update to Phase 1 Fact Sheet,

Mott MacDonald Limited, March 2010.

(3) "Montagu School, Weekley Glebe Road,

Kettering" GroundSure GeoInsight report,

GroundSure, Report HMD-326-387483,

30th March 2009.

The findings of these reports are summarised below.

They have been supplemented by the findings from

previous investigations carried out by Geotechnics

Limited for Northamptonshire County Council at

the site and by reports obtained from the British

Geological Survey (BGS). The previous investigations

carried out by Geotechnics Ltd are:-

(i) Ground Investigation at Northamptonshire

Academies, Montagu School, Report

PC093887, July 2009 (Volume 1 – Factual

Report and Volume 2 – Interpretative

Report).

(ii) Additional Ground Investigation at

Northamptonshire Academies, Montagu

School, Report PC094085, January 2010,

(Factual Report).

7.2 Geology

Information published by the BGS on published

geological maps of the area, geological memoirs and

other relevant literature was consulted. Where

appropriate, previous exploratory hole records have

been referred to, to give an indication of the regional

geology. For this site reference has been made to

the following:-

(i) Geological Survey Map 1:50.000

(Sheet No. 171)






(ii) Geological Survey Map 1:10,560

(Sheet No. SP 88 SE)

(iii) ''Geology of the Country around Kettering,

Corby and Oundle'' British Geological

Survey, 1963, HMSO

(iv) The BGS Lexicon of Named Rock Units

(http://www.bgs.ac.uk/lexicon/)

(v) Previous Exploratory Hole Records and

Study reports

7.2.1 Published Information

The 1:50,000 scale map shows the site (school and

field to the east of the school) to be underlain by

strata of the Great Oolite Formation of Middle

Jurassic age. Beneath the school the Rutland

Formation is shown with a tract of the

Wellingborough Limestone Member crossing the site

with a north west to south east alignment. An

outcrop of the Blisworth Limestone Formation is

shown below much of the field to the east

surrounded by the Rutland Formation.

The 1:10,560 scale geological map (Sheet SP 88 SE)

generally confirms the geology indicated on the

1:50,000 map but uses older geological names for

the strata. Below the field to the east of the school

the 1:10,560 map indicates that most of the site is

underlain by the Great Oolite Limestone (now the

Blisworth Limestone Formation) and the Upper

Estuarine Series (now the Rutland Formation). A thin

tract of the Upper Estuarine Limestone (now the

Wellingborough Limestone Member) is shown

outcropping in the south western corner.

The school site is also shown on the 1:10,560 map

to be underlain by the Upper Estuarine Limestone

and Upper Estuarine Series of Middle Jurassic age. A

fault is marked, trending south west to north east

across the north western part of the site with the

downthrow side to the south. To the south east of

the fault (which is most of the site) the Upper

Estuarine Series outcrops either side of a band of

Upper Estuarine Limestone about 50 to 60m wide

that runs approximately north – south from the

northern boundary to the centre of the site. A thin

tract of Lower Lincolnshire Limestone (now part of

the Linclonshire Limestone Formation) is shown

outcropping in the south western corner of the site.

To the north west of the fault, the Upper Estuarine

Series (no limestone) outcrops with a band of the

Lower Lincolnshire Limestone together with a small

area of the Lower Estuarine Series.

An area along the western boundary of the school

and in the north eastern corner, the site is shown as

a backfilled opencast ironstone quarry, the edge

being marked as up to about 40m inside the western

site boundary.

The Great Oolite Limestone or Blisworth Limestone

Formation, ranges in thickness from 4m to 8m,

consisting of light grey to white and yellowish

limestone with thin mudstone and calcareous

mudstone bands which are often found alternating.

The limestone can be oolitic, fossiliferous or shelly.

Oysters are particularly common. Around Kettering

the ooliths are less common and in the lower parts

of the formation the limestone is interbedded with

bands of clay. The base of the Great Oolite

Limestone overlies the Upper Estuarine Series.

The Upper Estuarine Series or Rutland Formation

forms an unconformable contact with the Lower

Lincolnshire Limestone (the Upper Lincolnshire

Limestone units being missing in this area) and

typically consist of mudstone with limestone and

sandstone beds. The basal beds of the Upper

Estuarine Series form a band of brown discontinuous

ironstone nodules and brown ferruginous

sandstones and are succeeded by pale grey clays and

silty clays. The upper beds are commonly found to

be grey marine mudstones which pass up into non

marine mudstones and siltstones. In this area the

Upper Estuarine Limestone beds (or

Wellingborough Limestone Member) outcrop within

the Upper Estuarine Series. These beds typically

range in thickness between 3m and 4m and comprise

bands of oyster bearing and sandy limestone and

calcareous mudstone along with greenish grey clays

with rootlets.

No superficial deposits are shown overlying the solid

geology.

The Groundsure Geoinsight Report (Ref: HMD-326-

387483) dated 30 March 2009, which was supplied

by the Engineer, confirms the geology indicated on

the published maps. The report also identifies a

section of artificial ground as shown on the

published maps and describes it as infilled ground.

This is likely to be the result of two phases of

historical surface ground workings shown in the

report to have taken place in 1950 and 1974. In

addition, the report gives a number of ground

related risk classifications including the following:-

• The site is in a radon affected area as between 10

and 30% of properties are above the Action

Level.






• Shallow mining hazards are classified as negligible.

• Shrink-swell hazards from clays are classified as

negligible for the Lower Estuarine Series, Lower

Lincolnshire Limestone and the Great Oolite

Limestone. The Upper Estuarine Series, which

outcrop, are classified as low.

• Landslide hazards are classified as very low for

the site.

• Ground dissolution and soluble rocks are

classified as very low for the Great Oolite

Limestone including isolated pockets outcropping

to the west. A low hazard classification is given

to the Lower Lincolnshire Limestone and parts of

the Upper Estuarine Series.

• Compressible ground hazards are moderate

where infilled ground is indicated along the

western boundary of the site. The rest of the site

is considered negligible.

• Running sand hazards are very low where infilled

ground is indicated and negligible across the rest

of the site.

7.2.2 Previous Investigation Data

The previous ground investigation carried out on the

school site (PC093887) showed variable ground

conditions. The locations of the exploratory holes

from the previous investigations are shown on the

Plan in Appendix 7. They can be briefly summarised

as follows:-

Made Ground

Made Ground was found in all the exploratory holes

with a thickness between 0.30m and 8.50m where

the full thickness was proved. The greatest thickness

was found in BH1A (8.50m) which was located close

to the north western corner of the site where the

old backfilled ironstone quarry was located.

Elsewhere a thickness of up to 3m was found.

Lincolnshire Limestone

Material that may form part of the Lower

Lincolnshire Limestone was found in WS2 at 3.30m

bgl in the south western corner of the site and in

WS3 at 3.85m bgl which was located close to the

northern edge of the site.

Upper Estuarine Series

Material considered to form part of the Upper

Estuarine Series was found in most of the

exploratory holes including S1, S2 and WS2 to WS8,

at depths of between 0.30m and 1.90m bgl

underlying the Made Ground and also in BH4 at

2.20m bgl (96.16m OD) below what is thought to be

the Upper Estuarine Limestone. It was typically

described as firm to stiff varying to very stiff slightly

sandy clay or slightly sandy slightly gravelly clay with

shell fragments, black carbonaceous fragments and

rootlets/root tracks. The gravel was composed of

limestone and occasionally sandstone. In S1 and

WS7, limestone was found at 1.40m and 1.70m bgl,

respectively (99.11 and 99.01m OD) at the base of

each exploratory hole, both holes being located

close together near to the centre of the eastern

boundary.

Upper Estuarine Limestone

Material thought to be the Upper Estuarine

Limestone was found in BH4 and S3 below the Made

Ground at depths of 1.20m and 0.65m bgl,

respectively (97.16 and 96.79m OD). It was found

to be 1.00m thick in BH4 and 1.35m was proved in

S3. In BH4 it was described as light brown slightly

gravelly sandy clay (gravel is limestone) over

yellowish brown clayey gravelly sand and in S3, it

was described as grey brown slightly sandy slightly

gravelly clay with limestone cobbles and boulders.

Groundwater

No groundwater was found during the drilling or

excavation of the exploratory holes. Standpipes

were installed in BH1A, BH4 and WS5 and during

the monitoring period (5th to 18th June 2009) no

groundwater was found in BH1A and BH4 located in

the north western corner of the site and the central

southern part of the site, respectively. In WS5,

located in the central northern part of the site, a

maximum groundwater level of 2.44m bgl (97.77m

OD) was recorded. This limited data suggests a

water table falling below the site to the west and

south or a perched water table in the region of

WS5. The groundwater regime is likely to be

complex due to the variable ground conditions

below the site.

The exploratory holes put down in the southern

part of the field to the east of the school

(PC094085) typically encountered up to between

2.5m and 5.0m of slightly sandy slightly gravelly clay

that is probably part of the Upper Estuarine Series.

A layer of sand was found at the base of SA3 and

mudstone in WS9 at 2.60m. No groundwater was

observed during the drilling or excavation of these

exploratory holes.






7.3 Site History

The summary included in the Geo-Environmental

Fact Sheets (Section 4, Mott MacDonald, April 2009

and Section 1, Update March 2010) indicates that

the site as a whole was used as agricultural land until

1952 and as allotments or open space thereafter. By

1992 the school had been developed on the site.

An Ironstone Quarry was operational on the edge

and to the north and northwest of the site from

1927. Evidence indicates that this was backfilled and

covered before 1992 and that more specifically it

was filled with household wastes between December

1968 and May 1973.

7.4 Hydrology

The works to date indicate that there are no surface

waters on the site and the closest noted open water

is the River Ise, 1.2km to the south east. Surface

water on site drains naturally into the ground or is

collected on the western site into a number of

soakaways presumably leading to the underlying

minor and major aquifer. A survey of these locations

was undertaken on 19th August 2010 and the findings

detailed in a Geotechnics Limited letter report dated

21st August 2010.

7.5 Hydrogeology

The underlying hydrogeology as detailed in previous

reports indicates several potential aquifers below the

site. These are the Blisworth Limestone, Lincolnshire

Limestone and Northampton Sand. The remainder

of the area is covered by largely impermeable Upper

or Lower Estuarine Beds.

The BGS GeoReport (BGS Report No.

GR_201337/1, September 2010) commissioned as

part of these works, details the anticipated

underlying conditions in the location of the

proposed eastern site soakaway as follows.

1) Blisworth Limestone, Minor Aquifer

(Secondary) with high soil leaching

potential, liable to be within a few metres of

the surface. Movement through fracture

flow and may contain perched waters above

underlying Rutland Formation mudstones.

2) Rutland Formation, multilayered aquifer

(Secondary or non-aquifer) with possibly

some water present in limestone and

sandstone horizons providing perched

waters.

3) Wellingborough Limestone Member, Minor

Aquifer (Secondary) with high soil leaching

potential if at surface. Movement by

fracture flow and may contain perched

waters under pressure where confined by

overlying mudstones.

4) Stamford Member, Minor Aquifer

(Secondary) probably unsaturated.

Movement mainly by intergranular flow.

5) Lincolnshire Limestone Formation, Major

Aquifer (Primary) probably unsaturated, but

very thin. Movement by fracture flow.

6) Grantham Formation, Non-Aquifer with

generally low permeability but intergranular

flow possible in sands to underlying

sandstones.

7) Northampton Sand Formation, Minor

Aquifer (Secondary). Movement by fracture

and intergranular flow, likely to be partially

saturated.

The general trend of underlying groundwaters could

possibly be to the south to south east for the site as

a whole, with the western side of the site probably

being biased slightly towards the south west, and the

eastern side towards the south east and the River

Ise. This is in an almost radial pattern away from the

high point to the north of the site and the Blisworth

Limestone outcrop in the centre of the site.

The report also details that whilst previously the

water level was considered to reside in the

Northamptonshire Sand Formation, this may have

been due to local workings and abstraction which

has now ceased. As such the true water level could

now reside in any of the underlying aquifers. This is

further complicated by the presence of units capable

of acting as aquitards that may also allow the local

transmission of groundwater.

The site is not currently within a designated

abstraction area but under the Water Framework

Directive and associated Basin Management plans,

could be considered as a potential future ground

water source.

The potential to act as a soakaway will depend

greatly on the level of interconnectedness of the

various underlying minor and major aquifers and the

local characteristics of the various intervening layers,

which may vary greatly over relatively small

distances.






In general, the underlying groundwater is considered

likely to be hard to very hard and may be

ferruginous at depth with high dissolved solids

content. It is also liable to be generally alkaline in

perched waters from the limestone units, possibly

becoming more neutral or acidic at depth within the

sands.

In terms of the potential to soakaway, the report

considers that some form of on-site storage to

reduce the fines by allowing settling before

discharge. This will help reduce the potential for

local mounding of the waters and blockage within

the underlying units as well as even out the rate at

which the water will be recharged.

The site is noted as being in a nitrate vulnerable

zone for ground and surface waters and has a low

risk of flooding from fluvial sources. The

Environment Agency website provides no flood

designation or risk assessment for the site.

7.6 Environmental Issues

Aside from the landfill, the only other noted off-site

environmental issues of potential significance

identified in the Mott MacDonald reports appear to

be:

1) A minor pollution incident to the south-east

of the site detailed as an oil spill from a

residential property.

2) Fuel station site 492m west of the site.

3) Eleven contemporary trade entries within

500m, mostly commercial buildings, garage

services and car dealers.

4) Lies within a Radon affected area where full

Radon protection measures are required.

On-site, the report also makes the following

observations:

1) Workshops on site used for brickmaking.

2) Flammable gas is stored on the site as are

small amounts of scientific chemicals in

laboratories.

3) Gas and electrical sub-stations are present

in the south of the site by the current

entrance to the western site.

4) A Pavilion on the southern side of the

eastern site may contain asbestos.

5) Made Ground may be present on the

eastern side of the site as evidenced by a

small embankment on the eastern side of

the western site.

7.7 Conceptual Site Model

The Conceptual Model adopted for the current

assessment, is based on the work undertaken by

Mott MacDonald Limited in their Phase 1

Preliminary Risk Assessment, Update to Phase 1 Fact

Sheet, dated March 2010. A diagrammatic

representation of the model is included in Appendix

E of the same document. The model appears to

ignore the presence of the Blisworth Limestone on

the eastern side of the site, but is only intended to

be diagrammatic. The model is further discussed in

Section 10 where it relates to environmental

matters.

8.0 INTERPRETATION

8.1 Ground Conditions

On the basis of the expected geology discussed in

Section 7.2 and the findings of the exploratory holes

it has been possible to classify the various strata

proved in the investigation into the following

divisions:-

Made Ground / Topsoil

Superficial Deposits

Great Oolite Limestone


Lincolnshire Limestone Group

Sections through the site are included in Appendix

15 to give an indication of the ground and

groundwater conditions at the site. These sections

are indicative only and reference should be made to

the Exploratory Hole Records for detailed

descriptions of the soils and the groundwater

conditions encountered. A summary of the material

properties are shown on Figures presented in

Appendix 16.






8.1.1 Made Ground / Topsoil

Made Ground with a thickness of between 0.30 and

0.40m was found in R01, TP2, TP3 and TP7.

Elsewhere Topsoil between 0.05m and 0.20m thick

was encountered from the ground surface. The

Made Ground typically comprised brown clayey

sandy gravel or sandy gravelly clay, the gravel being

composed of ash, flint, quartzite and limestone.

Further variation in the nature and thickness of the

Made Ground should be expected in areas between

and away from the exploratory holes.

8.1.2 Superficial Deposits

Soils that have been classified as Superficial Deposits

have been found below the Topsoil or Made Ground

in BH3, BH4, BH6, R02, TP2 to TP4 and TP7 which

were located in the southern and western parts of

the site. Where the underlying strata were reached,

a thickness of between 0.60m and 1.30m was found.

In the trial pits a thickness of up to 1.25m was

penetrated. It was typically described as stiff and very

stiff brown fissured / desiccated slightly sandy slightly

gravelly clay, the gravel being quartzite and

limestone.

The Natural Moisture Content was found to range

from 17% to 36% with an average of 24% (Fig 2.2,

Appendix 16). The Atterberg Limits classified the

soil as a clay of medium to very high plasticity, with

the Plasticity Index ranging from 27% to 43% (Fig 5.2,

Appendix 16). Two samples tested within the

Superficial Deposits recorded Total Sulphate

concentrations of 0.02% and 0.03%, respectively,

Soluble Sulphate of 10mg/l and 22mg/l, pH of 8.4 and

8.2 and Total Sulphur of 0.01% and 0.02%.

Particle Size Distribution tests on samples show the

following gradings

Clay/Silt : 46-82%

Sand : 16-18%

Gravel : 2-36%

8.1.3 Great Oolite Limestone

Material considered to form part of the Great

Oolite Limestone was encountered in all the

exploratory holes except possibly R01. The stratum

was possibly below the terminations of TP2 to TP4

and TP7. It was at a depth of between 0.05m and

1.50m below ground level (bgl) across the site. A

thickness of between 0.50m and 5.50m was

encountered where soils classified as the underlying

Upper Estuarine Series were found. The greatest

thickness was found in BH4 (5.50m) but it is possible

that the soils encountered below 3.70m bgl are part

of the Upper Estuarine Series.

The soils found were generally described as either

very stiff light brown sandy gravelly clay or very

dense sandy angular gravel of limestone, both strata

sometimes containing a low, medium and high

limestone cobble content. The granular deposits

were only found in BH1, BH5, TP1 and TP6 on the

western and northern edges of the area investigated

together with a thin layer (0.2m thick) in BH4 at

3.5m bgl. Generally the granular deposits were found

in the upper 1m bgl and in BH1 were of such a high

relative density that further penetration using cable

percussive drilling techniques was not possible below

depths of 1.49m bgl.

The clay deposits were found in all the exploratory

holes where the Great Oolite Limestone was

encountered, except TP6. In BH5 it was of such a

strength / density that further penetration was not

possible below a depth of 2.66m bgl.


from 7% to 17% with an average of 11% (Fig 2.1,


soil as a clay of medium plasticity, with Plasticity

Index values of 28% and 23% (Fig 5.1, Appendix 16).

Undrained shear strengths of 69kN/m2 and

146kN/m² were obtained from triaxial tests (Fig 4.1,

Appendix 16). A sample from BH4 3.20-3.55m was

too disturbed to undertake the triaxial test.. Where

full penetration of the SPT's occurred, 'N' values of

21, 23 and 27 were recorded (Fig 1.1, Appendix 16).

Full penetration was not achieved in 7 tests and

penetration after 50 blows ranged from 18mm to

247mm. Consolidation tests show Coefficients of

Volume Compressibility (Mv) values for an

approximate increase in stress of 100kN/m² of

around 0.2-0.3m²/MN (medium).

Four samples were analysed and recorded Total

Sulphate concentrations of between 0.03% and

0.07%, Soluble Sulphate of between 15mg/l and

90mg/l, pH of between 8.3 and 8.6 and Total Sulphur

of between 0.02% and 0.04%.

Particle Size Distribution tests carried out on

selected samples show the following gradings

Clay/Silt : 12-65%

Sand : 7-21%

Gravel : 15-81%

Cobbles : 0-33%






8.1.4 Upper Estuarine Series

Material considered to form part of the Upper

Estuarine Series was found in BH3, BH4, BH6 and

R01 to R03, below the eastern and southern parts of

the area investigated. It was typically found to

comprise very stiff dark grey and green grey sandy

calcareous clay or gravelly clay with shell fragments

and calcareous nodules. Layers of limestone or

siltstone were encountered and in the cable

percussive boreholes (BH3 and BH6) this layer

restricted progress of the hole and was recovered as

gravel sized fragments. In the drillholes they were

found to be between 0.30m (R01) and 1.90m (R03)

thick.


from 19% and 26% with an average of 23% (Fig 2.3,


soil as a clay of medium plasticity, with the Plasticity

Index between 15% and 22% (Fig 5.3, Appendix 16).

The undrained shear strengths determined in four

samples ranged from 106kN/m2 to 247 kN/m2 (Fig

4.2, Appendix 16). Where full penetration of the

SPT's occurred, 'N' values of between 28 to 35 were

found with an average of 32 (Fig 1.2, Appendix 16).

Full penetration was not achieved in 6 tests and

penetration after 50 blows ranged from16mm to

283mm. A Consolidation test shows a Coefficient of

Volume Compressibility (Mv) value for an

approximate increase in stress of 100kN/m² of

around 0.18m²/MN (medium).

A single sample recorded a Total Sulphate of 0.08%,

Soluble Sulphate of <10mg/l, pH of 8.4 and Total

Sulphur of 0.04%.

8.1.5 Lincolnshire Limestone Formation

and Lower Estuarine Series

Material that may comprise the Lincolnshire

Limestone was proved in R01 at a depth of 12.2m

bgl. It should be noted that this was in an open-hole

section of the drillhole where the driller has

described it as brown clay with possible limestone

bands, over a 2.40m thick layer of fractured

limestone. At a depth of 17.4m bgl the driller has

described the soil underlying the limestone as grey

clay and this may form part of the underlying Lower

Estuarine Series.

8.2 Groundwater

Groundwater was only recorded during the drilling

of R01. In R01 the driller records the presence of

water at 7.50m bgl. It is possible that this water is

entering from the Upper Estuarine Series. No

groundwater was observed in the other exploratory

holes.

Standpipes were installed in BH4, BH6 and R01 to

R03. Maximum groundwater levels of between

4.00m and 14.99m bgl (92.57m and 80.60m OD)

were recorded in the standpipes over the

monitoring period (3rd September to 9th November

2010).

Standpipes installed during the previous investigation

(PC093887) in BH1A, BH4 and WS5 recorded no

groundwater in BH1A and BH4 but in WS5 a

maximum water level of 2.44m bgl (97.77m OD) was

recorded. The water levels measured indicate

possible isolated perched water levels in some of the

exploratory holes.

It should be noted that during the monitoring of

R01, water was heard flowing into standpipe from

above the standing water level. It is considered

likely that this could be water flowing into the

standpipe from the upper limestone layer found in

the drillhole at between 5.90m and 6.20m bgl

(89.39m to 89.69m OD), the lower section of the

layer being just below the seal to the standpipe. This

water probably represents a water table perched on

the clays of the Upper Estuarine Series.

Seasonal variations in the groundwater regime

should be expected and further perched water levels

should be anticipated during and after wet weather.

9.0 GEOTECHNICAL

EVALUATION

9.1 Proposals

New school buildings are proposed on the open field

to the east of the existing school buildings. Most of

the existing school buildings are to be demolished

and a number of additional all-weather sports

pitches constructed in their place. The new school

buildings are to be of two to three storey

construction and the approximate footprint and

location is shown the Exploratory Hole Location

Plan in Appendix 7. A finished ground floor level of

approximately 98.5m OD is proposed. The area to

the south of the proposed building is to be given

over to hard-standing for car-parking and the access

road.






9.2 Foundation Design Principles

In formulating proposals for foundation and floor

slab design, the two primary controlling factors are

soil strength and foundation settlement. In general it

is the latter which is the primary determinand of

what is perceived to be satisfactory performance.

For clay soils, allowable bearing capacity is based on

undrained shear strength, although a Factor of Safety

of 3 is commonly adopted in order to ensure that

the loading is on the sensibly linear component of

the stress/strain curve for the soil. With time, the

clays will strengthen under the higher loadings as any

excess pore water pressures dissipate. Hence, the

worst case is at the time of initial loading and, for

gradually applied or static loading, bearing capacity

should progressively increase. For eccentric loading,

where peak load is at an extremity of the foundation,

this can be higher than the allowable load, provided

that the mean equivalent stress is within the

allowable value.

For granular or essentially free draining soils the

frictional characteristics and density will dominate

bearing capacity and this is generally much higher

than for clay soils. For normal spread foundations

conventional design is typically based on the stress

which would give rise to 25mm settlement. Actual

settlements will depend upon the type, period, load

intensity and width of the loaded area and the

thickness and compressibility of the soils below.

A further issue for foundations is the degree of

variability in the foundation soils. The adoption of a

lower bearing pressure than strength criteria would

indicate implicitly results in a larger foundation which

is likely to behave more in line with average

conditions and hence, for a given load, to result in

less differential settlement.

9.3 Foundation Solutions

Shallow strip/pad foundations are likely to be

suitable for the proposed buildings. To avoid

unpredictable total and differential settlements, the

foundations should be taken beneath any Made

Ground and bear into the strata of the Superficial

Deposits, Great Oolite Limestone or the Upper

Estuarine Series. A minimum foundation depth of

0.90m bgl is recommended.

Based on the foundations bearing into the stiff/very

stiff sandy gravelly clays of the Superficial Deposits

and the Great Oolite Limestone, a net safe bearing

capacity of 125 to 150kN/m² should be available for

strip and pad foundations, respectively. A greater

bearing capacity would be available in the granular

soils but it is recommended that it is limited to that

for the clay soils. Ideally, foundations for an

individual building should be founded within the

same material in order to provide more uniform

foundation behaviour and minimise any differential

settlement and where this is not possible the design

should take into account possible differential

behaviour. The settlements of any footings bearing

into the granular soils are likely to be small and

occur soon after the application of the load. Where

the foundations bear into the very stiff sandy gravelly

clay settlements of the order of about 25mm are

possible for a 2m wide footing loaded to 150kN/m2.

Hence differential settlements of approximately

20mm should be allowed for in the design for such

foundations.

The depth of the foundations should be checked in

relation to any trees or shrubs present or proposed

on the site or to any that will be removed as part of

the construction following the guidelines given in the

NHBC Standards, Chapter 4.2. A medium volume

change potential should be used for this assessment.

9.4 Excavations & Groundwater

Excavations on the site should be readily achievable

using conventional earth moving plant, although

more difficult conditions may be present in the

granular deposits of the Great Oolite Limestone.

Where foundation excavations extend to depths

greater than 1.00m they will need to be fully shored

if entry by personnel is required. Even for shallow

excavations the need for support will still need to be

evaluated under CDM regulations.

When exposed, the formation level for the

foundations should be kept dry and steps taken to

avoid disturbance. Blinding with concrete as soon as

possible after excavation and inspection would also

help minimise disturbance. Prior to construction the

formation should be inspected and any soft spots

removed. Where deep excavations are envisaged,

they are likely to require battering back to a safe

angle or some form of support will be necessary,

possibly in the form of trench-shore type boxes or

sheet piles. If sheet piling is proposed the presence

of the very hard strata of the Great Oolite

Limestone should be noted. Temporary works

design for such piles will need to ensure that there is

sufficient embedment of the piles and/or that

sufficient props are provided to maintain stability of

the excavation sides and base particularly where

man-entry is required.






Groundwater levels of up to about 4.48 to 6.72m bgl

(91.88 to 92.54m OD) have been recorded during

the investigation in the vicinity of the proposed

building and for excavations above this level,

groundwater is unlikely to present any significant

problems. Locally, perched water may be present

but this should be adequately dealt with by pumping

from sumps.

It should be noted that groundwater levels can vary

seasonally or following periods of prolonged wet or

dry weather and levels higher or lower than those

measured may be present during construction.

Further monitoring of the standpipes would give

more information in this regard.

9.5 Slab Design

No details are known regarding the proposed floor

slab. The long term settlement of the floor slab will

depend on a number of factors including the

structural design of the slab, the duration, intensity

and distribution of the applied loading as well as the

strength, compressibility and history of the soils

beneath slab. The preferred solution for the floor

slab will also depend on the type of foundation

adopted with a suspended floor slab typically being

used where the structural loads are carried on piled

foundations. The main types of floor slabs that could

be considered for the proposed buildings are:-

(i) A suspended floor slab

(ii) A ground bearing floor slab following the

removal of any Made Ground deposits and

replacement with imported granular material or

re-used soils excavated on site (following

removal of any unsuitable material) compacted

to an engineering specification.

9.6 Earthworks

As part of the development earthworks will take

place on the site to provide a platform for the

school buildings. A finished floor level of 98.5m OD

is proposed which is likely to require the excavation

of up to about 2m on the northern side of the

building and the placement of approximately 1 to 2m

of engineered fill along the southern side.

The materials excavated are likely to comprise the

deposits from the Superficial Deposits and the Great

Oolite Limestone. From the grading analyses carried

out these materials will probably conform to the

following classes as defined in the Specification for

Highways Works, Volume 1:-

Clay soils - Class 2B, 2C & 2D

Granular soils - Class 1A & 1C

A small amount of earthworks laboratory testing

was carried out and the results are summarised on

Figures 5 and 6 (Appendix 16). A tentative estimate

of the range of acceptable moisture contents for

each of the materials for re-use as engineering fill

based on these limited number of results assuming

minimum desirable CBR values or undrained shear

strengths for the compacted fill of 2% or 50kN/m²

respectively would be around 10% to 30%.

The variability of the deposits likely to be available is

such that defining an acceptable range of moisture

contents that covers all the available material is

difficult. This is likely to mean that the maximum use

of the available materials becomes difficult,

particulary where a Method Specification for

engineering fill (based on the guidelines contained in

the Specification for Highways Works) is adopted

using a single earthworks control factor such as

MCV or moisture content. A more appropriate

strategy may be to use an End-Product Specification

of density (an air voids ratio of less than 10% below

parking areas and 5% below buildings) and CBR

greater than 2%. This should be supplemented by

field compaction trials to maximise the use of the

available materials.

9.7 Buried Concrete

The results of the chemical testing can be

summarised as follows:-

Water Soluble Sulphate <10 to 90 mg/l

Total Sulphate 0.02 to 0.08 %

Total Sulphur 0.01 to 0.07 %

pH 7.7 to 8.6

Based on the procedures outlined in BRE Special

Digest 1 : 2005 and the test results, the Design

Sulphate Class for the site is DS-1 A check on the

potential presence of pyrite that can oxidise to form

sulphates has been undertaken and the Total

Potential Sulphate (TPS) determined from the Total

Sulphur Content and Acid soluble sulphate for the

stratum. The tests showed no oxidisable sulphates

to be present. Assuming mobile groundwater

conditions concrete should be designed for an

Aggressive Chemical Environment for Concrete

(ACEC) Class of AC-1.






9.8 Pavement Design

The conditions prevailing at the time of construction

will affect the CBR of the subgrade soil and its

strength. Research has shown the importance of the

equilibrium moisture content of the subgrade. The

relationship between soil suction and the moisture

content shows that a soil that becomes wet during

construction will retain water and will therefore be

weaker under the pavement in the equilibrium

condition than a foundation that has remained dry,

particularly for soils of low to medium plasticity.

Equilibrium CBR values for various materials for

poor and good construction conditions are given in a

report by the TRRL (Report 1132) and in Interim

Advice Note 73/06 "Design Guidance for Road

Pavement Foundations (Draft HD25)" produced by

the Highways Agency. The soils likely to be exposed

at formation level are the Superficial Deposits and

the clay deposits from the Great Oolite Limestone

and the Plasticity Indices (PI) obtained from these

materials were between 15 and 43%. The following

equilibrium CBR values are indicated for poor and

good construction conditions assuming a low water

table in the TRRL Report and the interim Advice

Note.

Equilibrium CBR (%)

PI Poor Conditions Good Conditions

20 3-4 6-8

30 3-3.5 4-6

40 2.5 3-3.5

The CBR values estimated from the DCP tests

ranged from 2.6% to in excess of 20% at depths

down to around 0.70m and 0.80m below ground

level. Laboratory CBR tests on recompacted

samples showed values of 2.6% to 24% on both

granular and clay samples.

On the basis of the exploratory holes, it is likely that

the Superficial Deposits and Great Oolite Limestone

strata will be present at formation level. For the clay

strata a preliminary design CBR of around 2.5 to 3%

should be considered. For sands and gravels an

equilibrium CBR in excess of 20% is indicated.

Where the site level is to be raised, a CBR

appropriate to the fill material used should be used

in the design. Caution must be exercised to ensure

that any soft areas are over-excavated, filled with

acceptable material and compacted in accordance

with an Engineering Specification. Materials likely to

be exposed are moisture sensitive and will soften

rapidly in the presence of water. The formation

should be promptly protected or if not possible, cut

with a good cross-fall and adequate drainage

provided. Proof rolling would aid the detection of

loose or soft pockets and allow appropriate

measures to be taken.

9.9 Soakaway Design

The use of soakaways are being considered for the

drainage of storm water run-off from the school

development. Prior to the fieldwork an inspection of

the soakaway installations on the existing school site

was undertaken by Geotechnics Ltd in consultation

with Cox Turner Morse, who are carrying out the

drainage design for the Client. A copy of the report

of the inspection is included in Appendix 17. To

determine the infiltration rates for these soakaways

it would be necessary to measure the dimensions of

the soakaways, their volume and the area through

which water is discharged and carry out a soakaway

test.

As part of the Additional Ground Investigation

(PC094085) three soakaway tests were carried out

close to the southern edge of the field to the east of

the existing school and the results are presented in

Report PC094085. Of these tests, two (SA1 and

SA2) were unsuccessful. The test in SA3 in the south

western corner was slightly more successful due to

the presence of a sand layer at the base of the trial

pit. As the infiltration rate was estimated by

extrapolating the test curve and the extent and

thickness of the sand layer is unknown, the

infiltration rate obtained from SA3 should be used

with caution.

As part of this investigation two borehole soakaway

tests were carried out to check on the suitability of

such installations. In the test carried out in R01 a

large quantity of water was pumped into the

borehole but it was not possible to raise the water

level. A soakage rate for R01 has been estimated

from the amount of water pumped into the

borehole. This gave a discharge rate of 111l/m²/min.

In R02, it was not possible to determine a soakage

rate using the method outlined in BRE Digest 363

(method adapted to allow for a borehole rather than

a pit), possibly due to the groundwater level of

about 4m bgl. As an alternative, a soakage rate has

been estimated using a method published by Kent

County Council which gave a discharge rate of

around 0.47l/m²/min.

The discharge from these two boreholes is probably

through the fractured limestone between 15.0m and

17.4 m bgl in R01 and the limestone layer in R02






between 4.7m and 5.9m bgl. An estimate of the

permeability of the limestone layer in R02 was

obtained from a rising head permeability test in the

standpipe which gave a permeability of 3.9x10-9.m/s.

However, in Borehole R01 the water flowing into

the standpipe from the upper layer of limestone

layer would have affected any permeability test. This

water is probably perched on the underlying clays

forming an aquiclude. The discharge from this

borehole (R01) is probably through the lower

fractured limestone and based on the volume of

water pumped into the drillhole during the soakaway

test, a permeability of the order of between 5x10-4 -

1x10-5 m/s can be estimated. It is suggested that if a

soakaway is required in the vicinity of R02 that it is

designed to reach a similar layer of fractured

limestone to that found in R01 although further

testing in this regard would be required.

10.0 ENVIRONMENTAL

ASSESSMENT

10.1 Legal Framework

Land contamination is an increasingly important

material planning consideration within the overall

planning regime. The planning authority is required

to consider the potential implications of

contamination both when it is developing structure

or local plans and when it is considering individual

applications for planning permission. Where

contamination is suspected or known to exist at a

site, a planning authority may require investigations

to be undertaken, for example, before granting

planning permission. Alternatively it may include

conditions on the permission itself requiring

appropriate investigation and, if necessary,

remediation.

Part IIA of the Environmental Protection Act 1990

has created a both a regime and framework within

which the identification and remediation of

contaminated land can be undertaken. This is then

further refined through the use of guidance on

specific aspects of the process produced by various

authorising bodies. Section 78A(2) of the Act

defines contaminated land for the purposes of Part

IIA as:

“any land which appears to the local authority in

whose area it is situated to be in such a

condition, by reason of substance 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) significant pollution of controlled waters is

being, or is likely to be caused.”

Part IIA is intended to complement the Planning

Regime and both Part IIA and the Planning Regime

are intended to embrace a “suitable for use

approach”. In the context of Part IIA, action is

necessary only where there are unacceptable risks

to health or the environment, taking in to account

the current use of the land and its environmental

setting (CLR7).

This report provides an assessment of the

contamination conditions considered likely to be

found at the site in the context of the legal

framework discussed above. As such this assessment

is based solely on our current knowledge and

understanding of the site as determined by the

information made available to us and our

understanding of the proposed development.

This report follows the principles and methodology

outlined in CLR11 and BS10175 which are currently

determined as UK best practice. The primary issues

of concern are Risks to Human Health, for which the

regulator acting as Statutory Consultee under the

Planning Regime is generally the Local Authority and

Risks to Controlled Waters for which the

appropriate consultee is the Environment Agency.

10.2 Proposed Site Use

For the purposes of this report, the contamination

risk assessment in respect of human health is

considered in the context of a proposed site use of

either a) allotments, b) industrial/commercial or c)

residential with or without plant uptake. These are

detailed as follows.

(a) This categorisation assumes that no residents

are present on the site so occupation is not

continuous. However, the site is used for the

growing of food for consumption either on or

off site and therefore includes an exposure

contribution from eating home-grown

vegetables. It also assumes that users will come

into direct dermal contact with soil materials.






(b) This categorisation assumes that no residents are

present and the site is normally used for

commercial and/or industrial purposes. Persons

using the site may potentially have short term

exposure only to open spaces on site.

(c) This categorisation assumes that residents may

have access to open space close to the home

with or without an exposure contribution from

eating home-grown vegetables.

The proposed use of the site will be the demolition

of the majority of the existing structures on the

western side of the site, with the area being

redeveloped as playing fields and possibly a

swimming pool. The eastern side of the site will be

redeveloped as a new school on the current open

land. The end use will therefore be similar to

current use but as such, none of the above

definitions truly reflects the real site situation. Given

that the CLEA residential models generally assume a

receptor younger than the age of those using the

school and does not have a specific open space or

school exposure model, the true model probably lies

somewhere between the industrial/commercial and

residential without plants models. On this basis, the

risk assessment has been undertaken using both

models concurrently. This will hopefully allow for

the incorporation of the precautionary principle to

allow for children as the most vulnerable receptors,

account for the potential for exposure to soil and

plant pathways but also to allow for a reduction in

the time that will be spent at the site and in the open

areas as opposed to using the assumptions made in

regard to the amounts of soil/plant/human

interaction in the residential model.

10.3 Conceptual Model

The Conceptual Model is a representation of the

current understanding of the site and the

surrounding environment. This includes and

incorporates an understanding of the geology,

groundwater, surface water bodies and potential

contamination processes acting on substances

present and migration pathways. It also takes into

account all identified potential pollutant linkages

using a source-pathway-receptor approach, based on

the proposed use of the site. Where any element of

the source-pathway-receptor linkage is absent, there

is considered to be no or negligible risk.

The Conceptual Model adopted for the current

assessment is based on the work undertaken by

Mott MacDonald Limited in their Phase 1

Preliminary Risk Assessment, Update to Phase 1 Fact

Sheet, dated March 2010.

10.3.1 Sources

The eastern half of the site and proposed location

for the new academy have historically been used as

open space, either as agricultural, allotment or

recreational land. The nearest identified potentially

significant source noted in the reports to date lies

adjacent to and under the north-western playing

fields on the western site at the location of an in-

filled former iron workings. This former landfill site

may potentially produce gas, vapours and leachate

including metals, organic and inorganic contaminants.

Other uses of the western site include its current

use as a school and previously as allotments and

agricultural ground.

The Mott MacDonald Update considers potential

contamination from possibly imported site fill

materials used in the construction of the school

buildings to be low and from the landfill to be

moderate. However, it should be noted that the

proposed new building on the eastern side of the

site would probably lie over 250m from the landfill

and would therefore be considered as lying beyond

its range of influence for a gas and vapour source.

10.3.2 Pathways - General

A pathway can be defined as: “A possible route or

means by which a receptor could be, or is exposed

to, or affected by a contaminant”. Pathways for

Human Health and Controlled Waters are

considered separately since they generally follow

different pathways.

Humans

The Contaminated Land Exposure Assessment

(CLEAUK) Model designed for Human Health

includes ingestion, dermal contact and inhalation

pathways. All of these pathways must be considered

when undertaking risk assessment.

The Mott Macdonald Update identifies human

pathways for direct contact, ingestion and inhalation

from site fill materials and inhalation from the landfill.






Controlled Waters

Controlled Waters for the purpose of this

investigation are defined as any lake, pond, river or

watercourse and groundwater. This therefore

includes water contained within the saturated

(phreatic) zone. Soil pore waters and waters

contained within the unsaturated (vadose) zone are

therefore outside the definition of controlled waters

and as such are not considered as receptors.

The Mott Macdonald Update identifies water

pathways for vertical and horizontal flow from site

fill materials and the potential for man made

pathways to be created during the works.

10.3.3 Receptors - General

A receptor in general terms is normally defined as

something that could be adversely affected by being

exposed to a contaminant. The receptors to be

considered in any assessment are therefore as

follows:

• Humans: End site users: children,

employees, adults, guests and construction

workers.

• Controlled Waters: Surface Water and

Groundwater

• Ecological receptors (wildlife)

• Building Fabric and Services

No ecological receptors have yet been identified that

could be adversely affected by site contamination

and as such they have been removed from

consideration. It has been assumed that no direct

linkage between the landfill and human receptors is

possible on the basis of its known location and that

it has sufficient cover material to prevent such direct

contact.

The River Ise should also be removed as a potential

surface water receptor due to the distance from the

site and that, given the intervening land use, no

direct surface flow is considered likely to reach the

river. Where a receptor is at one stage removed (i.e.

contamination has to pass through another receptor

to reach it) it should be considered as an extension

to the first receptor and does not usually require

separate consideration.

10.3.4 Site Specific Contamination Linkages

The following potential site specific Source-Pathway-

Receptor Linkages have been identified. These form

the basis of the most recently updated site specific

Conceptual Model:

• Metals, organic and inorganic contaminants

from the landfill reaching groundwater

receptors by leaching.

• Gas and vapours from the landfill reaching

human receptors by inhalation.

• Gas and vapours collecting in services and

building confined spaces leading to potential

build up of gas affecting human receptors

using such spaces.


from site fill materials reaching groundwater

receptors by leaching.


from site fill materials reaching human

receptors by direct contact, inhalation of

dusts and ingestion.

A diagrammatic representation of the Conceptual

Model is presented as Appendix E (Conceptual Site

Model) in the 2010 Mott Macdonald Update Report.

This preliminary model is of necessity generalised

and local variations may exist which have not been

taken into account.

10.4 Soil Testing

10.4.1 Introduction

Soil samples selected by Geotechnics Limited were

dispatched to laboratories for geochemical testing,

the results for which can be found in Appendix 13.

At the time of writing, Soil Guideline Values (SGVs)

have been published for five inorganic determinands;

arsenic, cadmium, mercury, nickel, and selenium and

six organic determinands; Benzene, Toluene, Xylene

Phenol, Dioxins and Ethylbenzene. These values are

provided mainly from the updated CLEA UK (V1.04)

model as screening values and are generally

considered conservative, hence where the SGVs are

not exceeded, the risk to humans from long term

exposure is considered low to negligible.

For substances for which there are no official

published SGVs or for which updated published

values are not yet available, comparison is made to

the previously published guidance to give an

indication of relative contaminant levels.






Since in general, the updated published SGV’s are

returning new values higher than the previous values,

the former are still considered reasonable for

comparison and guidance. It is generally assumed at

the time of writing that most current SGV’s will

probably increase rather than decrease. However,

reassessment against the new screening values will

be required as and when they become available.

In addition, reference was made to Generic

Assessment Criteria (GAC) for Human Health

(Chartered Institute of Environmental Health – LQM

2009 Second Edition) - GAC(LQM/CIEH) and Soil

Generic Assessment Criteria for Human Health Risk

Assessment (CL:AIRE 2010) a collection of screening

values derived using the current CLEA UK model

but not formally adopted or endorsed by DEFRA or

the EA. SGVs and GAC's both make assumptions

about the methods by which contamination can

reach receptors and assumptions about the amounts

each pathway can transmit in order to derive generic

values for basic screening purposes. In this case

reference will be made to both the "residential

without plant uptake" and the "industrial and

commercial" model and values where appropriate, as

outlined in Section 10.2.

As part of the CLEA assessment process, statistical

analysis of the results employs the concepts of the

Mean Value Test and the Maximum Value Test. The

Mean Value Test applies a factor to the results to

account for inherent uncertainty and predominantly

uses the number of trial holes and/or samples to

determine this factor.

The Mean Value Test gives a 95% confidence limit

(known as a US95) that contaminant concentrations

are likely to fall below this value at any particular

point across the site. However, the Mean Value

Test assumes that the data set will be “normally

distributed”. Where the result of the Mean Value

Test is heavily biased as the result of a single high

contaminant concentration value (i.e. where the data

set does not appear to be “normal”), the Maximum

Value Test is used. The Maximum Value Test

statistically determines whether the highest

concentration recorded is likely to be a statistical

outlier or not given the characteristics of the data

set. If proven to a suitable degree of confidence, the

outlier value should be removed from the data used

in the original Mean Value Test and the US95 should

be recalculated. The results of both statistical

methods are highly dependent on the size of the

data set.

Analysis of the US95 results and average data values

for each contaminant (as recommended in

"Guidance on comparing soil contamination data

with a critical concentration" CL:AIRE/CIEH 2008)

was undertaken. This guidance states that both the

average for the data set and the calculated US95

value need to lie above the chosen guidance value

before they can potentially be considered as

significant. In this case the critical value is the

appropriate SGV for the substance being analysed.

The SGV indicates the level for a given exposure

scenario where there is unlikely to be any significant

possibility of significant harm. Therefore where both

the average and the US95 exceed the critical value,

there is an as yet un-quantified possibility of harm.

The results of the statistical analysis of the soil data

are presented as a spreadsheet following the

analytical certificates in Appendix 13.

10.4.2 Soil Results Summary

The soil results from this investigation are of similar

magnitude to those located over most of the

western site and eastern site during previous site

investigations. The only exception to this was the

results of analyses of Borehole 1 and 1a samples

taken from a location within the landfill to the west

that were considered outliers and have therefore

been removed from further statistical consideration.

Selected data excluding the landfill samples from the

previous Geotechnics Limited investigations

(PC093887, July 2009, Volume 1 – Factual Report

and Additional Report PC094085, January 2010

understood to have been forwarded to the Client -

Communication dated 28th June 2010) has been

incorporated into a second statistical summary. The

identified SA2 0.3m hydrocarbon outlier, believed to

be the result of tarmac or localised organic cross

contamination, has also been removed from

statistical consideration.

The elevated levels of Chromium noted in red on

the spreadsheet reflect the fact that this analyte is

now assessed against both the CrIII and CrVI values.

It is considered unlikely that the CrVI percentage of

the total Chromium will exceed 10% even when

derived from a manufactured source as may be the

case in the landfill for instance. If correct, this

assumption would place the true values for the

whole site as being an average of 3.7 mg/kg and a

US95 of 4.4 mg/kg respectively. The average value

for CrVI therefore probably lies below and the US95

only marginally above the residential SGV of 4.3

mg/kg and would not therefore be significant. No

asbestos fibres have been detected in the samples

analysed and no fibrous materials were recorded

during the investigation.






Elevated levels of Vanadium in excess of the

residential SGV were detected in two samples (BH4

140mg/kg and WS8 0.1-0.3m) on the western site.

Arsenic was also elevated in excess of the residential

SGV at WS8 0.1-0.3m. It is noted however that both

samples also indicate slightly elevated results for

Nickel and Zinc, which could suggest a manufactured

source for these results. The sample underlying WS8

0.1-0.3m - WS8 0.3-1.2m - was also analysed and

showed no elevated levels of any of the above

contaminants suggesting that this is a highly localised

surface contamination and is probably unlikely to

significantly leach. It was noted on the day of the

soakaway monitoring visit (19th August 2010) that

motorcycle riding was being undertaken in this

general area.

However, on the basis that mineral abstraction for

metals (notably iron in the Northamptonshire

Sandstones) is known in the area, it could be the

case that the elevated levels are purely natural

increases or the result of incorporation of elevated

natural local material into site fills.

On removal of the values for the landfill and

erroneous SA2 hydrocarbon outlier, none of the

remaining combined samples were determined as

outliers to 95% or greater confidence levels and

therefore cannot be considered true hotspots. None

of the results to date are considered significant as

neither the average nor the US95 (or both) lie below

the residential SGV’s for that determinand.

10.5 Monitoring Results

10.5.1 Groundwater

The results of the groundwater samples taken on 9th

September 2010 are enclosed as Appendix 14. The

results indicate that the majority of analytes lie at

levels considered to be less significant than those in

the current drinking water standards. Sulphate is

slightly elevated in a couple of samples (HWS5 and

RO3) but could easily be the result of the hardness

expected in the waters from this area and the

underlying clay geology and is not therefore

considered significant from an environmental point.

Of more interest are the elevated Extractable

Petroleum Hydrocarbon (C10-C40) results from

RO2 and RO3. The results to date from the site

indicate that when elevated hydrocarbons are

located they tend to be heavy organic as opposed to

fuel materials and are also usually associated with

increases in organic matter.

However, whilst RO3 shows an appropriate increase

in organic matter and other determinands that

suggests it may be natural, a similar trend is not so

clearly apparent in the results for RO2. Whilst RO2

was being sampled, no visual or olfactory evidence of

oils was noted by the sampler and no significant bulk

gasses, carbon monoxide or sulphur dioxide that

might indicate the presence of fuel oils has been

found to date.

However, the value is still relatively low (1.6 ppm)

and the lack of elevated metals would tend to

contra-indicate it being a leachate from the landfill to

the west. RO2 was installed with a response zone

between 3.0 and 6.3m in presumed natural Upper

Esturine deposits. As such no definitive source for

this result has been located. The analytical

laboratory has provided a copy of the trace for this

sample and whilst there are some small individual

peaks, none stands out as being the prime source of

the elevated level. This would suggest it is not from

a fresh systematic single source such as would be

expected from contamination by the drilling, or

sampling process.

However it does have some slight similarities to

traces from very heavily degraded fuel oils and

rotting biological materials that have been in the

ground for long periods of time. This would also

explain the lack of any associated PAH, which would

usually disassociate from such material as transit

time increased. If the source were a local one (such

as school heating or brick laying area) it would be

generally expected that the other results would

reflect this more clearly. This leads either to the

conclusion that it is a highly localised source (past

spillage or storage in this area?) or that the

underlying fracture flow mechanism has

concentrated this material preferentially over other

locations. It may also be the case that this is the

result of the location being adjacent to a major

fracture receiving water from greater distance than

the other locations.

It is strongly recommended however, that further

samples be taken and analysed for organic materials

to determine whether or not this is an isolated or

systematic result for the location itself. Water can

vary quite significantly over time and as such the

particular waters sampled on the day of the visit may

not be representative of the underlying situation.






10.5.2 Ground Gas

The results of monitoring undertaken to date

indicate that there were marginally elevated levels of

carbon dioxide in several locations but no methane

and no measurable flow over most of the site. As

previously, the one exception is Borehole 1A

associated with the landfill site which showed

elevated levels of both methane and carbon dioxide

but no flow. The results are enclosed in Appendix 8.

CIRIA C665 (Assessing risks posed by hazardous

ground gases to buildings: CIRIA, 2008) uses Gas

Screening Values (GSV's) to determine the risk from

ground gas to a development and the appropriate

measures that should be incorporated into the

building design. The GSV for the site based on the

monitoring visits is based on the maximum gas

concentration recorded in percent combined with

the worst case flow rate in litres per hour. Where

any figure is less than the detection level of the

instrument for that parameter, the value used in the

calculation is required to default to the detection

level.

The worst case for the site excluding the landfill

borehole is a recorded value of 4.3% carbon dioxide

in HBH4 (western site) on the fourth visit. This gives

a GSV of 0.043 x 0.1 = 0.0043 l/hr. This value lies

significantly below the upper limit of CS1 of <0.07

and is therefore characterised as Characteristic

Situation 1 (CS1) meaning no special measures are

required and risk is considered very low. However,

as there is certainly carbon dioxide and methane

recorded above 5% from the landfill, it may be

prudent to consider raising the level of protection to

CS2 for any buildings proposed within 250m of the

landfill. When considering only the gases recorded

on the eastern side of the site, none have show any

significant levels of gas to date and no additional

measures are considered likely to be required.

The lack of any significant levels of hydrocarbons,

carbon monoxide or hydrogen sulphide being

detected in the boreholes would normally indicate

that it is unlikely that significant levels of Volatile

Organic Compounds (VOC’s) are present. Given the

number of visits and the range of atmospheric

conditions under which the monitoring has been

undertaken and the results obtained, the confidence

in the results is considered very good.

10.6 Risk Assessment

On the basis of the works to date, no significant

evidence of potential ground contamination beyond

that previously identified within the landfill area to

the northwest has been positively identified.

However, this does not preclude the potential for

isolated hotspots that have not been identified

during the previous investigations referenced above.

On the basis of the results to date, the potential for

such hotspots and for them to be potentially

significant is considered low. No significant potential

sources of gas or vapour have been determined in

the non landfill materials analysed to date. Source S1

(on-site school, anticipated made ground from

construction) identified in the Mott Macdonald site

model has been assessed and on the basis of the

results to date is not considered to be potentially

significant. The general risk of ground contamination

over the site, excepting the landfill area, is therefore

considered low.

In relation to the identified gas and vapour risk,

whilst the landfill is clearly producing gas it does not

appear to be producing significant quantities of

vapour. On the basis of the results from all the

locations monitored, the landfill does not appear to

be producing a significant flow or causing gas to pass

in significant quantities below the site. However, this

does not preclude the possibility that gas is migrating

along unknown and unmonitored pathways from the

landfill such as the fault identified on the geological

map to the north of the main site.

The associated risk is considered low to moderate

for the western site and will probably increase with

proximity to the landfill and may increase with

proximity to the fault or other as yet unidentified

pathways. In practice it would therefore be prudent

to consider appropriate gas safety measures and/or

detection procedures when working below site

levels or in confined spaces, especially when in

proximity to the landfill area (Receptor R3 –

Construction and maintenance workers).

The eastern site and proposed buildings are

considered unlikely to require significant gas

measures as they will generally lie beyond 250m of

the landfill boundary and no evidence of significant

levels of gas have been noted to date in the

monitoring results. The risk is therefore considered

low to very low (CS1) on this area of the site.






As only the landfill (Source S2 – off-site and on-site

historical landfill site) remains as a potentially

significant source, the risk to groundwater is

considered likely to be low to very low from on-site

sources. The risk from the landfill will depend mostly

on whether the site was a dilute and disperse

installation or was lined. In the first case it will then

also depend on the underlying geology in terms of

how it interacts to disperse the leachate (and at

what rate or reduction in concentration over

distance), in which directions it flows and at what

depth. If the latter case it will depend on how intact

the lining remains after nearly 40 years of burial. All

of these facts remain unknown and are beyond the

scope of the investigations to date. The water

samples analysed appear to indicate that no

significant leachate is reaching the eastern area of the

site though the result from RO2 remains

unexplained and further analysis (hydrocarbon

speciation) may provide additional information to

determine the source and if it is derived from the

western site.

On the basis of the results to date, potentially

significant risks may remain from the landfill (Source

S2) but these cannot yet be quantified fully. If it is

assumed that the site disperses into the underlying

aquifers, there is a potential for leachates to pass

below the site. This is considered unlikely to have

potentially significant effects on Site Workers

(Receptor R3) or Site End Users (Receptor R4)

simply due to the depth to such water below the site

(between 3 and 5 meters). However, such leaching

will also have a potential effect on underlying water

quality.

In regards to the potential to create man made or

preferential pathways (Pathway P4) the nature of the

underlying ground, its variable connectivity, the

existing soakaways and the water levels recorded to

date makes it appear unlikely that water significantly

rises from within the underlying aquifers when

encountered except possibly in times of exceptional

rain. As the underlying groundwater may already be

affected by the adjacent landfill, there is a potential

risk of upward movement of contamination, but this

is considered likely to be low to very low on the

basis of the results to date. Additional installations

are considered unlikely to make any significant

difference to the existing situation, especially given

they are likely to be restricted to the eastern side of

the site and that no on-site sources beyond the

landfill have been identified.

The addition of clean surface waters from the

eastern site into the underlying aquifer after

appropriate settlement in holding chambers or

ponds prior to disposal in the soakaway as

recommended by the BGS report, may improve the

underlying water quality by further diluting any

underlying landfill derived contamination.

10.7 Conclusions and

Recommendations

In conclusion, the only potential remaining links from

the Mott Macdonald model and comments would

appear to be:

1) A potential gas risk to site workers in

confined spaces (very low to moderate

depending on proximity to the landfill).

2) A risk from landfill leachate to the

underlying ground water primary and

secondary aquifers (low to moderate).

3) A risk from unidentified hotspots in site fill

materials (low to very low).

4) Radon gas (un-quantified – beyond scope of

works)

5) Asbestos in pavilion (un-quantified – beyond

scope of works).

In the case of gas, this can easily be mitigated by the

use of the appropriate safety protocols, monitoring

and testing being incorporated into the site works

procedures. Likewise in the case of unidentified

hotspots, procedures to identify and remove any

such hotspots located during the works should be

sufficient to mitigate any remaining risk rather than

undertaking significant amounts of additional testing

either pre or post demolition on the western site.

The risk to underlying waters will require further

consultation with the Environment Agency as

regulator of controlled waters and may be facilitated

by consideration of determining the source and

nature of the elevated result noted in the water

sample from RO2.

The above conclusions deliberately exclude any

consideration of works within the landfill boundary

on the basis that no works are currently proposed in

this area. If this situation was to change, a separate

risk assessment and possible additional investigation

works may be required. The conclusions also

specifically exclude consideration of Radon gas and

Asbestos in buildings, both of which issues are

beyond the scope of this report and risk assessment.






Signed for and on behalf of Geotechnics Limited.

C Lange

BSc

Senior Engineer

C G Swainston

BSc, PGCE, CGeol, FGS

Principal Geoenvironmental Engineer

D R Bracegirdle

BSc,MSc,CEng,FIMM,MICE,MHKIE,CGeol,FGS

Principal Engineer

1

APPENDIX 1

The Brief

GEOTECHNICAL INVESTIGATION ESTIMATE

Date : 18th August 2010

Estimate No : QC100203b

Title : Buccleuch Academy, Additional Works

Client : Willmott Dixon Construction

Rate Amount

£ £ p

General

1 Provide mobile welfare vehicle if local facilities are not made

available on site

Sum R/Only

2 Locate and level hole locations (priced within existing SI) Sum Geotechnics Ltd

3 Skip for disposal of clean spoil (priced within existing SI) Sum Geotechnics Ltd

4 Mobilise safety barriers (heras or similar) Sum

Inspection of Existing on site Soakaways

5 Provide 2 man team to locate 6No. existing soakaways, lift

inspection covers and report findings

1 Day

Trial Pitting

6 Provide JCB to excavate trial pits. Pits to be backfilled with

arisings and compacted. Full reinstatement not included.

1 Day

Rotary Drilling

7 Mobilise rotary drilling rig, equipment and crew to and from

site, including preparation and submission of copies of daily

site records.

1 Sum

8 Setting up and dismantling rotary rig at the position of each

borehole, including the extraction of casings and backfilling

borehole with arisings (total time for above, not exceeding 1

hour).

2 No

Item

No.Description

Quant-

ityUnit

9 Rotary open hole drill 100mm diameter, 0-20m below

ground level.

30 Lin.m

10 Rotary open hole drill 100mm diameter, 20-40m below

ground level.

Lin.m R/Only

11 Standard Penetration Test in rotary hole (0-20m) No R/Only

12 E.O. Items 9 - 10 for casing. 16 Lin.m

13 Set up and dismantle variable head permeability test within

rotary drill hole

2 No.

14 Carry out variable head permeability test in rotary drill hole

(provisional allowance of time)

2 Hr.

15 Time related activities not covered by other rates e.g.

awaiting further instructions, hand excavation of inspection

pits, reinstatement, etc.

2 Hr.

Well Installation

16 Provide and install simple standpipe/standpipe piezometer,

c/w gravel filter and bentonite seal.

30 Lin.m

17 Provide and install lockable flush cover. 2 No

18 Monitor Installations (priced within existing SI) 6 Visit Geotechnics Ltd

Total fieldwork cost based upon estimated quantities above.

Laboratory Testing

19 Determination of moisture content 4 No.

20 Determination of particle size distribution 2 No.

21 Sedimentation by pipette 2 No.

22 Determination of dry density/moisture content relationship

using 2.5kg rammer

4 No.

23 E.O Item 22 using 4.5kg rammer No. R/Only

24 Determination of California Bearing Ratio - 2.5kg compaction

at natural moisture content

4 No.

25 E.O Item 24 using 4.5kg rammer No. R/Only

Professional Services & Reporting

21 Enquiries to Statutory Undertakers Sum Client

22 Provision of on site Services Information Sum Client

23 Provide desk top study to confirm the groundwater flow

regime of the site area

Sum

24 Engineering supervision on site 2 Day

25 Professional Services for carrying out project management,

logging and incorporate information into combined

factual/interpretation report.

Sum

26 Undertake interpretation/analysis.

a Principal Engineer - Geotechnical. 4 Hr

b Principal Engineer - Environmental (to update existing Mott

MacDonald Conceptual Site Model)

3 Hr

Estimate Total (excluding VAT)

Insurance excess to be reimbursed should services not

disclosed by the client prior to starting contract be

accidentally damaged during site works (see Clause 4 of our

Conditions of Offer

Sum

Your Ref : - Our Ref : AD/QC100203 Date : 15 September 2010 Willmott Dixon Construction Limited Chantry House High Street Coleshill Birmingham B46 3BP For the attention of Mr Chris Kinman Dear Sirs Geotechnical and Geoenvironmental Investigation Quotation : Northamptonshire Academies,

Weekly Glebe Ground Investigation. We refer to our recent meeting of 25th June 2010 regarding additional Ground Investigation at the Montagu School site and respond with our quotation for a scope of work which we consider would fulfil your requirements within the area of the proposed new school site not previously covered by the original investigation undertaken by Geotechnics Ltd in May 2009 carried out to the instructions of Mott MacDonald (the Engineer) on behalf of the Client, Northamptonshire County Council. Our quotation is based on an investigation which involves the review of existing desk study information, a single day trial pitting survey to approximate depths of 4m, the sinking of 6No. boreholes using cable percussion techniques to approximate depths of 8m, in situ testing, laboratory testing, groundwater/gas monitoring and reporting as detailed on the attached estimate. All work will be re-measured on completion and Geotechnics Ltd will advise you verbally and subsequently in writing should site and ground conditions dictate that additional or amended works be considered necessary and the estimated costs and contract period are likely to be exceeded. In formulating our quotation, we have estimated quantities and costs on the following basis and included a provisional sum for laboratory testing: a) Undisturbed samples or Standard Penetration Tests (SPT’s) at 1m intervals to 5m depth and 1.5m

thereafter. b) Disturbed samples associated with each SPT or U100 and small disturbed samples at the approximate

rate of 1 no. per metre drilled or excavated and at each change in strata.

c) We have allowed for 1No. class one sample to be taken within each scheduled borehole to allow for undrained shear strength and consolidation testing to new euro code standards.

d) We have assumed drive on access by a Land Rover towed cable percussion boring rig and a mechanical

excavator is available, together with unlimited headroom. We have also provided rates for other activities which may be required such as: a) The excavation of inspection pits at every borehole location.

b) Chiselling obstructions c) Monitoring of existing standpipes installed during the original fieldworks (May 2009) for gas/groundwater

levels in the long term. We have included a contingency sum to cover these items, as considered appropriate to the available information. As detailed on the enclosed Conditions of Offer, the Employer, or his appointed representative, will be responsible for notifying Geotechnics Ltd of the location of any services, utilities or buried structures present on the site. No work can be started on site until such information is made available. In the absence of such information we would be pleased to undertake enquiries with the statutory undertakers or, in the case of private sites, organise an on-site services search by a specialist company. The costs for undertaking these services are included on the enclosed estimate as rate-only items. It should be recognised that the information from a specialist company can be provided in CAD format to become a permanent record for inclusion in the site H&S File for the project. We ask you to note that it is company policy to excavate service inspection pits to 1.2m at all borehole locations unless instructed in writing by the Client/Engineer not to do so. Any such written instruction would relieve Geotechnics Ltd of any liability for damage to underground apparatus. According to our present commitments we could implement the desk study review process immediately and, subject to its findings and the availability of the information on services, fieldwork would commence within about two weeks from receipt of your written instruction. We estimate that the fieldwork would take about one week and our final report would be submitted to you within six weeks of the end of site work. Preliminary information would be made available to you throughout. We would draw to your attention the enclosed Conditions of Offer, Investigation Techniques and General Notes and trust that you will find these of assistance in evaluating our submission. If you do not consider that our proposals meet your requirements and wish to amend the scope of work, we would be pleased to respond to your comments.

Should you require any other information in the meantime or wish to discuss the scope of the work proposed, please do not hesitate to contact the undersigned. Yours faithfully A Demetriou - Estimator for GEOTECHNICS LIMITED – Head Office email: [email protected] Enc

GEOTECHNICAL INVESTIGATION ESTIMATE

Date : 30th June 2010

Estimate No : QC100203a

Title : Northamptonshire Academies, Weekly Glebe Ground

Investigation

Client : Willmot Dixon Construction Limited

Rate Amount

£ £ p

General

1 Provide on site toilet and store including mobilisation to and

from site

Sum

2 Locate and level hole locations Sum

3 Skip for disposal of clean spoil Sum

Trial Pitting

4 Provide JCB to excavate trial pits. Pits to be backfilled with

arisings and compacted. Full reinstatement not included.

1 Day

5 Provide breaker attachment for JCB. Day R/Only

Cable Percussion Boring

6 Mobilise cable percussion boring rig, equipment and crew to

and from site, including preparation and submission of copies

of daily site records.

Sum

7 Setting up and dismantling cable percussion boring rig at the

position of each borehole, including the extraction of casings

and backfilling borehole with arisings (total time for above,

not exceeding 1 hour).

6 No.

8 Time related activities not covered by other rates e.g.

awaiting further instructions, hand excavation of inspection

pits, reinstatement, etc.

6 Hr.

Item

No.Description

Quant-

ityUnit

9 Cable percussion boring 150mm dia.through soils and fills, 0-

10m below ground level.

48 Lin.m

10 Cable percussion boring 150mm dia. through soils and fills,

10-20m below ground level.

Lin.m R/Only

11 E.O. Item 9 - 10 for advancing borehole through rock or

other obstruction.

Hr R/Only

Sampling and Insitu Testing

12 Undisturbed 100mm diameter sample (U100) 12 No

13 Undisturbed class one - 100mm diameter sample (UT100) 6 No

14 Standard Penetration Test (0-20m) 24 No

15 Small disturbed/groundwater sample. 48 No

16 Bulk disturbed sample. 24 No

17 Environmental/contamination sampling setts 12 No

Well Installation

18 Provide and install simple standpipe/standpipe piezometer,

c/w gravel filter and bentonite seal.

24 Lin.m

19 Provide and install lockable flush cover. 3 No

20 Monitor Installations 6 Visit

21 E.O item 20 to monitor existing 3No. Installations present on

site from orginal GI dated July 2009 on same day

Visit R/Only

Total fieldwork cost based upon estimated quantities above.

Laboratory Testing - Geotechnical

22 Suggested allowance for Laboratory Testing (at enclosed

Standard Rates April 2010) Includes 15% discount

Allow

Laboratory Testing - Contamination

23 Geotechnics - Soil Suite 1 10 Suite

24 Geotechnics - Soil Suite 2 (Dependant option) Suite R/Only

25 Geotechnics - Soil Suite 6 10 Suite



28 Suggested allowance for Contamination Analysis based on

CLR8 guidelines - Water (if encountered)

Suite R/Only

Professional Services & Reporting

29 Enquiries to Statutory Undertakers Sum Client

30 Provision On Site Services Information Sum Client

31 Review of existing Groundshore desk study dated March

2009

Sum

32 Engineering supervision on site 5 Day

33 Professional Services for carrying out project management,

logging and preparation of factual report.

Sum

34 Undertake interpretation/analysis.

a Principal Engineer - Geotechnical. 8 Hr

b Principal Engineer - Environmental. 6 Hr

Estimate Total (excluding VAT)

Insurance excess to be reimbursed should services not

disclosed by the client prior to starting contract be

accidentally damaged during site works (see Clause 4 of our

Conditions of Offer

Sum

From: Adam Demetriou Sent: 18 August 2010 13:16 To: 'Chris Kinman'; '[email protected]' Cc: Terry Clark; Trevor Hardie; Chris Swainston; Clive Lange; Tomasz Zuk; PC104350 Subject: RE: Buccleuch Academy, Additional Works Attachments: Site Investigation Pre-Meeting160810.doc; Buccleuch Academy, Original Scope of Works) - BoQ.xls; Exploratory Hole Location Plan.pdf; Buccleuch Academy, Additional Works - Quotation QC100203b.xls

Dear Chris Please find attached our quotation to provide additional Site Investigation Services for the above site as per attached Minutes of our Meeting dated 16th August 2010. Our intention is to incorporate the additional site works into the investigation already agreed (attached original scope of works) to commence Monday 23rd to Friday 27th August 2010 Also attached is the revised exploratory hole location plan. Proposed groundwater and gas monitoring

installations are preliminary scheduled to be installed within BH2, BH4, BH6, RO1 & RO2. Please can you advise at your earliest convenience if works are to proceed on this basis. Kind Regards

Adam Demetriou - Estimator

Geotechnics Ltd - Head Office

The Geotechnical Centre 203 Torrington Avenue Tile Hill Coventry CV4 9AP Tel: 024 76694664 Fax: 024 76694642 Mob: 07919215719 [email protected] www.geotechnics.co.uk

2

APPENDIX 2

Site Location Plan

SITE LOCATION PLAN

Ground InvestigationatBuccleuch Academy, KetteringforWillmott Dixon Construction Limited

© Crown Copyright Reserved, OS License Number: 100020449

3

APPENDIX 3

Site Photographs

Location of Soakaway east of Sports Hall (SA1) SA1 Eastern Chamber

SA1 Central Chamber SA1 Western Chamber with borehole

PHOTOGRAPHS


Project : Montagu School, Kettering

SA2 Northern Chamber SA2 Southern Chamber

Soakaway West of Sports Hall with Borehole (SA2)

PHOTOGRAPHS



Location of Soakaway Far West of Sports Hall (SA3) SA3 Western Chamber

SA3 Central Chamber SA3 Eastern Chamber with Borehole

PHOTOGRAPHS



Location of Soakaway south of Humanities Block (SA4) SA4 Western Chamber

SA4 Central Chamber

PHOTOGRAPHS



Location of Soakaway west of Former English Block (SA5) SA5 Eastern Chamber

SA5 Western Chamber with Borehole

PHOTOGRAPHS



Location of Soakaway north of Former English Block (SA6) SA6 No borehole visible

PHOTOGRAPHS



4

APPENDIX 4

Borehole Records

Form REP002 Rev 1

DATA SHEET - Symbols and Abbreviations used on Records Sample Types B Bulk disturbed sample

BLK Block sample

C Core sample

D Small disturbed sample (tub/jar)

E Environmental test sample

ES Environmental soil sample

EW Environmental water sample

G Gas sample

L Liner sample

P Piston sample (PF - failed P sample)

TW Thin walled push in sample

U Open Tube - 102mm diameter with blows to take sample. (UF - failed U sample)

UT Thin wall open drive tube sampler - 102mm diameter with blows to take sample. (UTF - failed UT sample)

V Vial sample

W Water sample

# Sample Not Recovered

Insitu Testing / Properties S Standard Penetration Test

(SPT) C SPT with cone VN Strength from Insitu Vane HV Strength from Hand Vane PP Strength from Pocket

Penetrometer (All other strengths from undrained

triaxial testing) w% Water content N SPT Result -/- Blows/penetration (mm)

after 150mm seating. -*/- Total blows/penetration (mm) ( ) Extrapolated value

Rotary Core

RQD Rock Quality Designation (% of intact core >100mm) FRACTURE INDEX Fractures/metre FRACTURE Maximum SPACING (mm) Minimum NI Non-intact core NR No core recovery (where core recovery is unknown it is assumed to be at the base of the run)

Groundwater Water Strike Depth Water Rose To

Instrumentation Seal Filter Seal

Strata

Made Ground Type 1 Type 2 Topsoil Cobbles and Boulders Gravel

Sand Silt Clay Peat Note: Composite soil types shown by combined symbols Chalk Limestone Sandstone Coal

Strata, Continued Mudstone Siltstone Metamorphic Rock Fine Grained Medium Grained Coarse Grained Igneous Rock Fine Grained Medium Grained Coarse Grained

Backfill Materials Arisings Bentonite Seal Concrete Fine Gravel Filter General Fill Gravel Filter Grout Sand Filter Tarmacadam

5

APPENDIX 5

Rotary Drillhole Records

Form REP002 Rev 1


BLK Block sample

C Core sample





G Gas sample

L Liner sample





V Vial sample

W Water sample







Rotary Core




Strata





RO3 3.00-6.00

PHOTOGRAPHS


Project : Buccleuch Academy, Kettering

RO3 6.00-9.00

PHOTOGRAPHS



6

APPENDIX 6

Trial Pit Records

Form REP002 Rev 1


BLK Block sample

C Core sample





G Gas sample

L Liner sample





V Vial sample

W Water sample







Rotary Core




Strata





TP1 (Spoil)

TP1

PHOTOGRAPHS



TP2 (Spoil)

PHOTOGRAPHS



TP3 (Spoil)

TP3

PHOTOGRAPHS



TP4 (inside)

TP4 (Spoil)

PHOTOGRAPHS



TP5 (Spoil)

TP5

PHOTOGRAPHS



TP6 (Spoil)

TP6

PHOTOGRAPHS



TP7 (Spoil)

TP7

PHOTOGRAPHS



7

APPENDIX 7

Exploratory Hole Location Plan

8

APPENDIX 8

Monitoring Results

FIELDWORK - Water Level MonitoringProject

Client

Project No

Borehole

Instrument (dia. mm)

Depth to Base (m)

Filter Zone

Level

(m)

Depth

(m)Date

BUCCLEUCH ACADEMY, KETTERINGPC104350

Sheet No

Time LevelDepth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

BH4 BH6 HBH1A HBH4 HBS5 RO1

S (50mm)

6.80

0.50-6.80

97.74 m OD

S (50mm)

5.00

0.50-5.00

97.07 m OD

(0mm)

8.60

(0mm)

9.94

(0mm)

4.65

S (50mm)

19.00

6.00-19.00

95.59 m OD

WILLMOTT DIXON CONSTRUCTION LTD 1

3 Sep 2010 5.86 91.88

3 Sep 2010 DRY

3 Sep 2010 11.30 84.29

10 Sep 2010 6.00 91.74

10 Sep 2010 DRY

10 Sep 2010 DRY

10 Sep 2010 DRY

10 Sep 2010 2.32

10 Sep 2010 14.60 80.99

30 Sep 2010 6.32 91.42

30 Sep 2010 DRY

30 Sep 2010 DRY

30 Sep 2010 DRY

30 Sep 2010 2.04

30 Sep 2010 14.99 80.60

12 Oct 2010 5.75 91.99

12 Oct 2010 DRY

12 Oct 2010 DRY

12 Oct 2010 DRY

12 Oct 2010 2.27

12 Oct 2010 10.96 84.63

26 Oct 2010 6.04 91.70

26 Oct 2010 DRY

26 Oct 2010 DRY

26 Oct 2010 DRY

26 Oct 2010 2.31

26 Oct 2010 14.94 80.65

9 Nov 2010 5.90 91.84

9 Nov 2010 4.37 92.70

9 Nov 2010 8.59

Remarks

Symbols andabbreviations areexplained on theaccompanyingkey sheet.

All dimensionsare in metres.


Client

Project No

Borehole


Depth to Base (m)

Filter Zone

Level

(m)

Depth

(m)Date


Sheet No

Time LevelDepth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

BH4 BH6 HBH1A HBH4 HBS5 RO1

S (50mm)

6.80

0.50-6.80

97.74 m OD

S (50mm)

5.00

0.50-5.00

97.07 m OD

(0mm)

8.60

(0mm)

9.94

(0mm)

4.65

S (50mm)

19.00

6.00-19.00

95.59 m OD


9 Nov 2010 DRY

9 Nov 2010 1.38

9 Nov 2010 14.83 80.76

Remarks




Client

Project No

Borehole


Depth to Base (m)

Filter Zone

Level

(m)

Depth

(m)Date


Sheet No

Time LevelDepth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

Depth

(m)Level

RO2 RO3

S (50mm)

6.30

0.50-6.30

96.57 m OD

S (50mm)

9.00

0.50-9.00

99.26 m OD


3 Sep 2010 4.48 92.09

3 Sep 2010 6.72 92.54

10 Sep 2010 4.64 91.93

10 Sep 2010 6.82 92.44

30 Sep 2010 4.89 91.68

30 Sep 2010 7.22 92.04

12 Oct 2010 4.39 92.18

12 Oct 2010 6.58 92.68

26 Oct 2010 4.68 91.89

26 Oct 2010 6.64 92.62

9 Nov 2010 4.00 92.57

9 Nov 2010 6.48 92.78

Remarks



FIELDWORK - Insitu Gas Monitoring - Instrument RecordProject Project No

BoreholeClient Sheet No.

Installation Details

Installation Type DiameterDepth to Base Cover TypeFilter Zone Ground LevelDate Installed

Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)

Hydrogen Sulphide H2S

(ppm)

Carbon Monoxide

CO (ppm)

Remarks

BUCCLEUCH ACADEMY, KETTERING PC104350

WILLMOTT DIXON CONSTRUCTION LTD 1 (1 of 2)

BH4

Standpipe 50mm

6.80m Flush lockable protective cover

0.50 - 6.80m 97.74 m OD

25 August 2010

3-Sep-2010 5.86 <1 <1

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 0.6 18.3

3-Sep-2010 <0.1 <2 0.7 18.0

3-Sep-2010 <0.1 <2 0.7 17.6

3-Sep-2010 <0.1 <2 0.7 17.6

10-Sep-2010 6.00 <1 <1

10-Sep-2010 <0.1 <2 <0.1 20.7

10-Sep-2010 <0.1 <2 0.2 20.3

10-Sep-2010 <0.1 <2 0.4 19.6

10-Sep-2010 <0.1 <2 0.7 18.4

10-Sep-2010 <0.1 <2 0.7 18.4

30-Sep-2010 6.32 <1 <1

30-Sep-2010 <0.1 <2 0.1 20.5

30-Sep-2010 <0.1 <2 1.1 17.1

30-Sep-2010 <0.1 <2 1.3 16.1

30-Sep-2010 <0.1 <2 1.4 15.5

30-Sep-2010 <0.1 <2 1.4 15.5

12-Oct-2010 5.75 <1 <1

12-Oct-2010 <0.1 <2 0.1 20.7

12-Oct-2010 <0.1 <2 0.4 20.3

12-Oct-2010 <0.1 <2 0.4 20.3

26-Oct-2010 6.04 <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 0.2 20.3

26-Oct-2010 <0.1 <2 0.1 20.4

26-Oct-2010 <0.1 <2 0.1 20.4

9-Nov-2010 5.90 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 0.9 17.8

9-Nov-2010 <0.1 <2 0.8 18.6

9-Nov-2010 <0.1 <2 0.8 18.6





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)

Flow Rate (Peak/Stable)

(l/hr)

Remarks



BH4

Standpipe 50mm


0.50 - 6.80m 97.74 m OD

25 August 2010

3-Sep-2010 1006 12.50 +0.26 -0.0

3-Sep-2010

3-Sep-2010

3-Sep-2010

3-Sep-2010

3-Sep-2010

10-Sep-2010 1000 15.00 +0.23 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.40 +0.37 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.80 -0.03 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1005 8.00 +0.00 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.10 +0.10 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



BH6

Standpipe 50mm


0.50 - 5.00m 97.07 m OD

26 August 2010

3-Sep-2010 DRY <1 <1

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 0.2 20.7

3-Sep-2010 <0.1 <2 0.2 20.7

10-Sep-2010 DRY <1 <1

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 <0.1 <2 1.0 19.7

10-Sep-2010 <0.1 <2 1.0 19.7

30-Sep-2010 DRY <1 <1

30-Sep-2010 <0.1 <2 0.1 20.5

30-Sep-2010 <0.1 <2 1.9 18.0

30-Sep-2010 <0.1 <2 1.9 18.0

12-Oct-2010 DRY <1 <1

12-Oct-2010 <0.1 <2 0.1 20.7

12-Oct-2010 <0.1 <2 0.1 20.7

12-Oct-2010 <0.1 <2 0.1 20.7

26-Oct-2010 DRY <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 1.2 19.5

26-Oct-2010 <0.1 <2 1.2 19.5

9-Nov-2010 4.37 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 3.9 13.8

9-Nov-2010 <0.1 <2 3.9 13.0

9-Nov-2010 <0.1 <2 3.9 13.0





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



BH6

Standpipe 50mm


0.50 - 5.00m 97.07 m OD

26 August 2010

3-Sep-2010 1006 12.80 +1.57 -0.0

3-Sep-2010

3-Sep-2010

3-Sep-2010

10-Sep-2010 1001 15.00 +1.51 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.30 +0.30 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.80 +1.36 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1004 7.80 +1.05 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.10 +0.29 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



HBH1A

Electronic piezometer -

8.60m

-

10-Sep-2010 DRY <1 <1

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 21.0 >lel 22.0 1.2

10-Sep-2010 21.6 >lel 22.0 0.3

10-Sep-2010 21.9 >lel 22.0 <0.1

10-Sep-2010 21.9 >lel 22.0 <0.1

30-Sep-2010 DRY <1 4

30-Sep-2010 <0.1 <2 0.2 20.3

30-Sep-2010 32.2 >lel 24.1 1.0

30-Sep-2010 32.7 >lel 24.0 <0.1

30-Sep-2010 32.7 >lel 24.0 <0.1

12-Oct-2010 DRY <1 <1

12-Oct-2010 <0.1 <2 0.1 20.5

12-Oct-2010 25.9 >lel 23.5 3.5

12-Oct-2010 25.9 >lel 22.6 1.2

12-Oct-2010 26.1 >lel 22.6 0.9

12-Oct-2010 26.1 >lel 22.6 0.9

26-Oct-2010 DRY <1 <1

26-Oct-2010 <0.1 <2 0.2 20.2

26-Oct-2010 13.5 >lel 20.3 1.0

26-Oct-2010 13.6 >lel 20.3 <0.1

26-Oct-2010 13.6 >lel 20.3 <0.1

9-Nov-2010 8.59 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.4

9-Nov-2010 35.2 >lel 24.3 1.6

9-Nov-2010 35.2 >lel 24.5 <0.1

9-Nov-2010 35.2 >lel 24.5 <0.1





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



HBH1A


8.60m

-

10-Sep-2010 1001 14.30 +0.78 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.20 +0.66 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.70 +0.99 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1005 7.20 +1.20 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.00 +1.38 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



HBH4


9.94m

-

10-Sep-2010 DRY <1 <1

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 <0.1 <2 4.1 13.4

10-Sep-2010 <0.1 <2 4.1 13.0

10-Sep-2010 <0.1 <2 4.1 13.0

30-Sep-2010 DRY <1 <1

30-Sep-2010 <0.1 <2 0.1 20.6

30-Sep-2010 <0.1 <2 3.1 17.6

30-Sep-2010 <0.1 <2 3.2 17.4

30-Sep-2010 <0.1 <2 3.6 17.0

30-Sep-2010 <0.1 <2 3.7 16.8

30-Sep-2010 <0.1 <2 3.7 16.8

12-Oct-2010 DRY <1 <1

12-Oct-2010 <0.1 <2 0.1 20.6

12-Oct-2010 <0.1 <2 3.0 17.2

12-Oct-2010 <0.1 <2 3.2 16.8

12-Oct-2010 <0.1 <2 3.2 16.8

26-Oct-2010 DRY <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 4.3 15.5

26-Oct-2010 <0.1 <2 4.3 14.4

26-Oct-2010 <0.1 <2 4.3 14.4

9-Nov-2010 DRY <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 4.1 16.0

9-Nov-2010 <0.1 <2 4.1 14.9

9-Nov-2010 <0.1 <2 4.1 14.9





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



HBH4


9.94m

-

10-Sep-2010 1001 14.40 +1.00 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.10 +0.57 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.60 +0.56 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1005 6.80 +0.27 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 960 7.00 +1.99 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



HBS5


4.65m

-

10-Sep-2010 2.32 <1 <1

10-Sep-2010 <0.1 <2 0.1 20.3

10-Sep-2010 <0.1 <2 0.3 20.3

10-Sep-2010 <0.1 <2 0.3 20.3

30-Sep-2010 2.04 <1 <1

30-Sep-2010 <0.1 <2 0.1 20.6

30-Sep-2010 <0.1 <2 0.2 20.0

30-Sep-2010 <0.1 <2 0.2 20.0

12-Oct-2010 2.27 <1 <1

12-Oct-2010 <0.1 <2 0.1 20.5

12-Oct-2010 <0.1 <2 0.5 19.4

12-Oct-2010 <0.1 <2 0.5 19.4

26-Oct-2010 2.31 <1 <1

26-Oct-2010 <0.1 <0.1 0.1 20.5

26-Oct-2010 <0.1 <0.1 0.3 20.5

26-Oct-2010 <0.1 <0.1 0.3 19.7

9-Nov-2010 1.38 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 0.2 19.9

9-Nov-2010 <0.1 <2 0.2 19.9





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



HBS5


4.65m

-

10-Sep-2010 1000 14.60 +0.53 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 997 15.70 +0.39 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.60 +0.37 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1005 6.80 +1.67 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 960 7.20 +2.03 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



RO1

Standpipe 50mm


6.00 - 19.00m 95.59 m OD

24 August 2010

3-Sep-2010 11.30 <1 <1

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 0.1 20.1

3-Sep-2010 <0.1 <2 0.1 20.1

10-Sep-2010 14.60 <1 <1

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 <0.1 <2 0.1 20.8

30-Sep-2010 14.99 <1 <1

30-Sep-2010 <0.1 <2 0.1 20.6

30-Sep-2010 <0.1 <2 0.1 20.3

30-Sep-2010 <0.1 <2 0.1 20.3

12-Oct-2010 10.96 <1 <1

12-Oct-2010 <0.1 <2 0.1 20.5

12-Oct-2010 <0.1 <2 0.1 20.5

12-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 14.94 <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 2.7 17.9

26-Oct-2010 <0.1 <2 2.7 17.9

9-Nov-2010 14.83 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 0.1 20.5





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



RO1

Standpipe 50mm


6.00 - 19.00m 95.59 m OD

24 August 2010

3-Sep-2010 1007 12.40 +0.94 -0.0

3-Sep-2010

3-Sep-2010

3-Sep-2010

10-Sep-2010 1001 14.60 +0.87 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.00 -0.04 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.70 -0.21 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1005 7.20 +0.46 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.10 -0.57 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



RO2

Standpipe 50mm


0.50 - 6.30m 96.57 m OD

25 August 2010

3-Sep-2010 4.48 <1 <1

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 4.64 <1 <1

10-Sep-2010 <0.1 <2 0.1 20.8

10-Sep-2010 <0.1 <2 0.6 19.9

10-Sep-2010 <0.1 <2 0.6 19.9

30-Sep-2010 4.89 <1 <1

30-Sep-2010 <0.1 <2 0.1 20.5

30-Sep-2010 <0.1 <2 1.9 15.6

30-Sep-2010 <0.1 <2 1.5 16.5

30-Sep-2010 <0.1 <2 1.5 16.5

12-Oct-2010 4.39 <1 <1

12-Oct-2010 <0.1 <2 0.1 20.4

12-Oct-2010 <0.1 <2 0.1 20.6

12-Oct-2010 <0.1 <2 0.1 20.6

26-Oct-2010 4.68 <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 0.8 17.6

26-Oct-2010 <0.1 <2 0.6 18.6

26-Oct-2010 <0.1 <2 0.6 19.7

26-Oct-2010 <0.1 <2 0.3 19.7

9-Nov-2010 4.00 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 1.5 16.3

9-Nov-2010 <0.1 <2 3.6 14.6

9-Nov-2010 <0.1 <2 3.7 13.9

9-Nov-2010 <0.1 <2 3.7 13.9





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



RO2

Standpipe 50mm


0.50 - 6.30m 96.57 m OD

25 August 2010

3-Sep-2010 1007 12.90 +0.67 -0.0

3-Sep-2010

3-Sep-2010

3-Sep-2010

10-Sep-2010 1001 14.30 -0.10 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.20 +0.18 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.70 +0.55 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1004 7.80 +0.06 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.20 +0.53 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010





Date Time

Remarks

Form 003/1

Depth to Water

(m bgl)

Methane

CH4 (% VOL)

Methane

CH4 (% LEL)

Carbon Dioxide CO2

(% VOL)

Oxygen

O2 (% VOL)


(ppm)

Carbon Monoxide

CO (ppm)

Remarks



RO3

Standpipe 50mm


0.50 - 9.00m 99.26 m OD

25 August 2010

3-Sep-2010 6.72 <1 <1

3-Sep-2010 <0.1 <2 0.1 20.8

3-Sep-2010 <0.1 <2 1.9 18.6

3-Sep-2010 <0.1 <2 1.9 18.6

10-Sep-2010 6.82 <1 <1

10-Sep-2010 <0.1 <2 <0.1 20.7

10-Sep-2010 <0.1 <2 0.3 20.4

10-Sep-2010 <0.1 <2 0.3 20.4

30-Sep-2010 7.22 <1 <1

30-Sep-2010 <0.1 <2 <0.1 20.6

30-Sep-2010 <0.1 <2 0.2 20.6

30-Sep-2010 <0.1 <2 0.2 20.6

12-Oct-2010 6.58 <1 <1

12-Oct-2010 <0.1 <2 0.1 20.7

12-Oct-2010 <0.1 <2 0.1 20.7

12-Oct-2010 <0.1 <2 0.1 20.7

26-Oct-2010 6.64 <1 <1

26-Oct-2010 <0.1 <2 0.1 20.5

26-Oct-2010 <0.1 <2 1.0 20.0

26-Oct-2010 <0.1 <2 1.3 19.7

26-Oct-2010 <0.1 <2 1.3 19.7

9-Nov-2010 6.48 <1 <1

9-Nov-2010 <0.1 <2 0.1 20.5

9-Nov-2010 <0.1 <2 1.2 19.3

9-Nov-2010 <0.1 <2 1.9 19.0

9-Nov-2010 <0.1 <2 1.9 19.0





Date Time

Remarks

Form 003/1

Barometric Pressure

(mBars)

Air Temp.

(DegC)

Diff. Pressure

(mBars)


(l/hr)

Remarks



RO3

Standpipe 50mm


0.50 - 9.00m 99.26 m OD

25 August 2010

3-Sep-2010 1006 12.60 +0.03 -0.0

3-Sep-2010

3-Sep-2010

3-Sep-2010

10-Sep-2010 1000 15.10 +0.03 -0.0

10-Sep-2010

10-Sep-2010

10-Sep-2010

30-Sep-2010 998 16.30 +0.53 -0.0

30-Sep-2010

30-Sep-2010

30-Sep-2010

12-Oct-2010 1005 11.80 +0.00 -0.0

12-Oct-2010

12-Oct-2010

12-Oct-2010

26-Oct-2010 1004 8.00 +0.11 -0.0

26-Oct-2010

26-Oct-2010

26-Oct-2010

26-Oct-2010

9-Nov-2010 961 7.00 +0.93 -0.0

9-Nov-2010

9-Nov-2010

9-Nov-2010

9-Nov-2010

9

APPENDIX 9

Soakaway Test Results

10APPENDIX 10

In Situ Permeability Test Results

Project No

Hole dia (m)=0.110

Pipe dia (m)= 0.050

(minutes) (m) (minutes) (m)

0.0 6.080 Datum (m) =

0.5 6.070

1.0 6.070

1.5 6.060

2.0 6.060

2.5 6.060

3.0 6.060

3.5 6.060 WL

4.0 6.060 Before 6.250

4.5 6.050 After 6.250

5.0 6.050

6.0 6.050

7.0 6.050

8.0 6.050

9.0 6.050

10.0 6.050

15.0 6.040

20.0 6.040

25.0 6.040 m

30.0 6.040 m

40.0 6.030 m

50.0 6.020 m

60.0 6.020 m

m

m2

m

mins

5.839

0.000 mins

60.000 mins

(1.440)

(1.380)

Depth of

borehole below

GL (m)

(GENERAL APPROACH)VARIABLE HEAD TEST

Differential head at start (Ho)

Diameter for shape factor (Ds)

(1.440)

3.350

Depth to

Ground

water (m) =

0.110

PC104350

Project RO2Borehole

Top of

Casing

Test No

Date 10.09.10

1 ( C)

ELAPSED TIME

Buccleuch Academy, Kettering

ELAPSED

TIME

(Continued)

(negative value if above ground)

Height of

casing/Datum

above GL (m) =

Remarks

Head at Time t1 (H1)

Head at Time t2 (H2)

0.00

Depth of casing

below GL (m)=

Depth to Standing Water Level

Depth to Induced Water Level 6.080

4.640

1.96E-03

0.050

1.380

60.000

3.98E-09

KS

m/sec

Intake factor (F)

Time (t1)

Time (t2)

Permeability (K)=A/(F[t2-t1])*loge(H1/H2)

Area of borehole (A)

Persons present during test:

Head at end of Test (Hf)

Time Elapsed at end of test (tf)

Type of Test

INSITU TESTING - Permeability (Borehole)Form INS005 Rev 1

Sheet 1 of 2

Depth of water

below Top of

Casing

(continued)

4.64

Length of

test section

(m) = 3.35

2.90

Depth of water

below Top of

Casing

Shape factor derived from BS5930: 1999: Section 4

Diameter for flow (D f)

Test Length (L)

Falling Head

Project No

(mins) (m) (m)

6.08 (1.44) 1.00

0.50 6.07 (1.43) 0.99

1.00 6.07 (1.43) 0.99

1.50 6.06 (1.42) 0.99

2.00 6.06 (1.42) 0.99

2.50 6.06 (1.42) 0.99

3.00 6.06 (1.42) 0.99

3.50 6.06 (1.42) 0.99

4.00 6.06 (1.42) 0.99

4.50 6.05 (1.41) 0.98

5.00 6.05 (1.41) 0.98

6.00 6.05 (1.41) 0.98

7.00 6.05 (1.41) 0.98

8.00 6.05 (1.41) 0.98

9.00 6.05 (1.41) 0.98

10.00 6.05 (1.41) 0.98

15.00 6.04 (1.40) 0.97

20.00 6.04 (1.40) 0.97

25.00 6.04 (1.40) 0.97

30.00 6.04 (1.40) 0.97

40.00 6.03 (1.39) 0.97

50.00 6.02 (1.38) 0.96

60.00 6.02 (1.38) 0.96

6.05

6.04

PC104350 Date

6.05

6.05

Time

Remarks

6.07

6.07

6.06

6.06

6.06

6.06

6.04

INSITU TESTING - Permeability (Borehole)

Relative Depth

from Ground

Level

Form INS005 Rev 1

Sheet 2 of 2

Buccleuch Academy, Kettering Borehole RO2

Test No 1 ( C)Project

10.09.10

Shape factor derived from BS5930: 1999: Section 4

Ht Ht/HoMeasured

Depth

(m)

6.08

6.04

6.04

6.05

6.06

6.06

6.05

6.05

6.05

6.03

6.02

6.02

Time at ratio H/Ho=.37 :

0

10

20

30

40

50

60

70

80

90

100

110

120

130

0.101.00

Head ratio Ht/Ho (log scale)

Ela

pse

d t

ime t

(m

inu

tes)

11

APPENDIX 11

DCP Test Results

Form REP002 Rev 1


BLK Block sample

C Core sample





G Gas sample

L Liner sample





V Vial sample

W Water sample







Rotary Core




Strata





INSITU TESTING - DCP field test

0 0 1 110 0

1 1 1 180 70

1 2 1 210 100

2 4 1 290 180

2 6 1 340 230

2 8 1 380 270

2 10 1 430 320

2 12 1 470 360

2 14 1 510 400

2 16 1 530 420

2 18 1 570 460

2 20 1 595 485

3 23 1 630 520

3 26 1 670 560

3 29 1 710 600

3 32 1 750 640

3 35 1 780 670

3 38 1 850 740

3 41 1 880 770

3 44 1 910 800

3 47 1 940 830

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0 0 1

180 4 1

180 4 1

400 14 1

400 14 1

670 35 1

670 35 1

740 38 1

740 38 1

830 47 1

Remarks

Depth below

ground level

(mm)

22.00

12.86

Blows

No.Blows Total

45.00 5.40

DCP

mm/blow

CBR %

(TRRL)

Ro

d

20.31

10.82

26.49

23.33

10.00

11.51

Reading

(mm)

Depth bgl

(mm)

BLOW S

No.

Sheet

1 of 2

Client Willmot Dixon Construction Ltd

Section/Chainage No

Test No

Project No

Initial Zero Reading

Date

Test Started at (m)

Project Buccleugh Academy, Kettering

Form INS003 Rev 3

25/08/2010

0.00

DCP1

PC104350

110

0

100

200

300

400

500

600

700

800

900

0 10 20 30 40 50

No. of BLOWS

Dep

th b

elo

w g

ro

un

d level (m

m)



Section/Chainage No

Test No

Project No


Date

Test Started at (m)


Form INS003 Rev 3

25/08/2010

0.00

DCP1

PC104350

110

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1 110 1

2 1

3 1

4 1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Remarks

Sheet

2 of 2

Reading

(mm)

Depth below

ground level

(mm)

Ro

d

Blows Total

Depth bgl

(mm)

BLOW S

No.

DCP

mm/blow

CBR %

(TRRL)

Blows

No.

Final Reading

940

Zero

ReadingRod No


0 0 1 100 0

1 1 1 190 90

1 2 1 230 130

1 3 1 250 150

1 4 1 290 190

1 5 1 340 240

1 6 1 390 290

1 7 1 460 360

2 9 1 510 410

2 11 1 570 470

2 13 1 610 510

2 15 1 660 560

2 17 1 710 610

2 19 1 760 660

2 21 1 790 690

2 23 1 830 730

2 25 1 865 765

2 27 1 900 800

2 29 1 920 820

1 30 1 940 840

1 31 1 950 850

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0 0 1

90 1 1

90 1 1

190 4 1

190 4 1

360 7 1

360 7 1

660 19 1

660 19 1

800 27 1

Remarks

Depth below

ground level

(mm)

33.33

56.67

Blows

No.Blows Total

90.00 2.60

DCP

mm/blow

CBR %

(TRRL)

Ro

d

4.23

10.05

14.66

25.00

17.50

7.42

Reading

(mm)

Depth bgl

(mm)

BLOW S

No.

Sheet

1 of 2


Section/Chainage No

Test No

Project No


Date

Test Started at (m)


Form INS003 Rev 3

25/08/2010

0.00

DCP2

PC104350

100

0

100

200

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35

No. of BLOWS

Dep

th b

elo

w g

ro

un

d level (m

m)



Section/Chainage No

Test No

Project No


Date

Test Started at (m)


Form INS003 Rev 3

25/08/2010

0.00

DCP2

PC104350

100

1

1

1

1

800 27 1

850 31 1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1 100 1

2 1

3 1

4 1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Remarks

Sheet

2 of 2

Reading

(mm)

Depth below

ground level

(mm)

Ro

d

Blows Total

Depth bgl

(mm)

BLOW S

No.

DCP

mm/blow

CBR %

(TRRL)

12.50 20.92

Blows

No.

Final Reading

950

Zero

ReadingRod No


0 0 1 100 0

1 1 1 170 70

1 2 1 210 110

1 3 1 240 140

1 4 1 270 170

1 5 1 300 200

1 6 1 320 220

2 8 1 360 260

3 11 1 410 310

3 14 1 460 360

3 17 1 500 400

3 20 1 550 450

3 23 1 590 490

3 26 1 630 530

3 29 1 680 580

3 32 1 730 630

3 35 1 790 690

2 37 1 840 740

2 39 1 890 790

2 41 1 930 830

1 42 1 950 850

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

0 0 1

110 2 1

110 2 1

220 6 1

220 6 1

490 23 1

490 23 1

580 29 1

580 29 1

690 35 1

Remarks

Buccleugh Academy, Kettering

Form INS003 Rev 3

25/08/2010

0.00

DCP3

PC104350

100Client Willmot Dixon Construction Ltd

Section/Chainage No

Test No

Project No


Date

Test Started at (m)

Project

Sheet

1 of 2

9.09

Reading

(mm)

Depth bgl

(mm)

BLOW S

No.

16.24

17.25

13.96

15.00

18.33

Depth below

ground level

(mm)

27.50

15.88

Blows

No.Blows Total

55.00 4.37

DCP

mm/blow

CBR %

(TRRL)

Ro

d

0

100

200

300

400

500

600

700

800

900

0 10 20 30 40 50

No. of BLOWS

Dep

th b

elo

w g

ro

un

d level (m

m)


Buccleugh Academy, Kettering

Form INS003 Rev 3

25/08/2010

0.00

DCP3

PC104350

100Client Willmot Dixon Construction Ltd

Section/Chainage No

Test No

Project No


Date

Test Started at (m)

Project

1

1

1

1

690 35 1

850 42 1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1 100 1

2 1

3 1

4 1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Remarks

Final Reading

950

Zero

ReadingRod No

Depth bgl

(mm)

BLOW S

No.

DCP

mm/blow

CBR %

(TRRL)

22.86 11.05

Blows

No.

Reading

(mm)

Depth below

ground level

(mm)

Ro

d

Blows Total

Sheet

2 of 2

12

APPENDIX 12

Laboratory Test Results - Geotechnical

Form REP001 Rev 1

DATA SHEET - Laboratory Test Symbols

Classification and Strength

Symbol C - Clay M - Silt (0 - containing organic matter) Plasticity L - Low I - Intermediate H - High V - Very High E - Extremely High Ip Plasticity Index

% % Retained on 425 µm sieve, shown under Ip value

wL Liquid Limit

wP Plastic Limit

NP Non-Plastic

NAT Sample tested in natural state

w Moisture Content

p Particle Density

Test Quick undrained triaxial tests SS Single stage - 102mm diameter.

S3 Single stage - set of 3

38mm diameter.

MS Multistage - 102mm diameter.

D Drained Test

HV Hand Vane

PP Pocket Penetrometer (kg/cm²)

UT Unsuitable for Test

γb Bulk Density

σ3 Triaxial Cell Pressure

σ1 - σ3 Deviator Stress

## Excessive Strain

cu Undrained Cohesion

c Cohesion Intercept

φ Angle of Shearing Resistance

Linear Linear Shrinkage Shrink

Consolidation

mv Coefficient of Volume Compressibility

cv50 Coefficient of Consolidation - Log t

cv90 Coefficient of Consolidation - √t

Rock

UF Unacceptable Failure

Chemical Analysis

Acid Soluble Total sulphate in specimen, expressed as SO3 %, value in brackets expressed as SO4 %

Water Soluble Soluble sulphate in 2:1 water : soil extract, expressed as SO3 g/l, value in brackets expressed as SO4 g/l

In Water Sulphate content of groundwater, expressed as SO3 g/l, value in brackets expressed as SO4 g/l

pH pH value

Organic content Organic content expressed as a percentage of dry weight

Chloride Chloride Ion content expressed as a percentage of dry weight

MCV, Compaction, CBR

MCV Moisture Condition Value at natural

moisture content

MCC Moisture Condition Calibration

CCV Chalk Crushing Value

Compaction

Type 2.5 = BS 2.5 kg Rammer 4.5 = BS 4.5 kg Rammer V = BS Vibrating Hammer

γb Bulk Density

γd Dry Density

CBR California Bearing Ratio

Type 2.5 = Test on Specimen Recompacted using BS 2.5 kg Rammer 4.5 = As above but using BS 4.5 kg Rammer V = As above but using BS Vibrating Hammer M = Test on open drive mould specimen cut in field S = Soaked Specimen

Top CBR at top of mould

Bottom CBR at bottom of mould

ND None Detected

All tests performed in accordance with BS 1377 : Parts 1-9 : 1990 incorporating amendments where appropriate.

d

LABORATORY RESULTS - Classification and Strength

Project Project No:

Sample

Hole Depth Type Description

Depth)

Sample

PC104350BUCCLEUCH ACADEMY, KETTERING

Ref

m

(Specimen

Classification Strength

Symbol lp Test γb σ σ −σ cw w w

L p 3 31

Mg/m kN/m3 2

kN/m2

kN/m2

(>425)

c

kN/m2

upd

( )

%

γd

( )(

%%%

Avg

BH1 B C449690.40-

0.90

(0.40)

Light brown silty sandy GRAVEL with

cobbles

6.9

BH3 D C454580.40

(0.40)

Brown slightly sandy slightly gravelly

CLAY

CH 27

(5%)

53 26 17

BH3 U C449551.20-

1.55

(1.20)

Brown sandy CLAY CI 28

(42%)

47 19

16 SS 2.03 25 139 69

##

69

BH3 B C449751.60-

2.20

(1.60)

Light brown slightly sandy slightly

gravelly CLAY

10

BH3 U C449543.00-

3.45

(3.00)

Brown sandy CLAY CI 15

(NAT)

36 21

25 SS 1.99 60 254 127 127

BH4 D C454750.30

(0.30)


CLAY

CH 32

(15%)

53 21 21

BH4 U C449911.20-

1.65

(1.20)


CLAY

17 SS 2.15 25 292 146

##

146

BH4 U C449923.20-

3.55

(3.20)


CLAY

(See Test Remarks Sheet for further

information)

CI 23

(20%)

38 15

7.4 SS UT 60 UT

BH5 B C449840.30-

0.80

(0.30)

White grey silty sandy GRAVEL 10

BH5 B C449861.20-

1.70

(1.20)


gravelly CLAY

12

BH6 D C454981.00

(1.00)


CLAY

CI 28

(7%)

48 20 19

BH6 U C449942.20-

2.65

(2.20)

Grey mottled brown slightly sandy

slightly CLAY

CI 22

(NAT)

42 20

20 SS 1.99 50 233 117 117

RO3 C C460463.70-

3.95

(3.70)

Brown slightly sandy silty CLAY CI 21

(NAT)

47 26

19 SS 2.11 80 493 247 247

RO3 C C460455.25-

5.50

(5.25)

Greenish grey slightly sandy CLAY 26 SS 2.09 110 212 106 106

TP5 B C449670.50

(0.50)


CLAY

CV 43

(10%)

73 30 36

Remarks Tests performed in accordance with BS 1377: 1990

LABORATORY RESULTS - Classification and Strength

Project Project No:

Sample


Depth)

Sample


Ref

m

(Specimen

Classification Strength

Symbol lp Test γb σ σ −σ cw w w

L p 3 31

Mg/m kN/m3 2

kN/m2

kN/m2

(>425)

c

kN/m2

upd

( )

%

γd

( )(

%%%

Avg

TP5 B C449660.75

(0.75)

Brown gravelly slightly sandy gravelly

CLAY.

25

TP6 B C449650.75

(0.75)

Light brown clayey GRAVEL with

cobbles

9.4

Remarks Tests performed in accordance with BS 1377: 1990

LABORATORY RESULTS - Particle Size Distribution

Project:

Project No: PC104350

BUCCLEUCH ACADEMY, KETTERING Hole

Sample Depth

Sample Type

Sample Ref

BH1

0.40-0.90m

B

C44969

Sample Description

Light brown silty sandy GRAVEL with cobbles

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT

Classification Fine Medium Coarse

SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

3

11

43

33

0

Size Percentage Finer Size Percentage Finer

Sieving Method

Fine Particle Analysis

Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

0.80

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

67

-

54

52

-

38

35

33

-

28

-

24

22

20

-

17

-

14

-

13

9

6

3

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette

Uniformity Coefficient

2468.49

SAND

GRAVEL

COBBLES

BOULDERS

Classification

10

CLAY

SILT

Remarks 21/09/2010Test performed in accordance with BS 1377: Part 2: 1990


Project:



Sample Depth

Sample Type

Sample Ref

BH3

1.60-2.20m

B

C44975

Sample Description

Light brown slightly sandy slightly gravelly CLAY

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT


SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

7

14

35

0

0


Sieving Method


Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

0.53

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

100

100

100

97

-

88

85

81

-

71

-

65

63

60

-

57

-

54

-

51

38

17

7

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette


225.99

SAND

GRAVEL

COBBLES

BOULDERS

Classification

44

CLAY

SILT



Project:



Sample Depth

Sample Type

Sample Ref

BH5

0.30-0.80m

B

C44984

Sample Description

White grey silty sandy GRAVEL

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT


SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

4

7

81

0

0


Sieving Method


Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

0.66

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

100

100

74

57

-

35

32

28

-

22

-

19

17

16

-

15

-

14

-

12

9

6

4

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette


1556.38

SAND

GRAVEL

COBBLES

BOULDERS

Classification

8

CLAY

SILT



Project:



Sample Depth

Sample Type

Sample Ref

BH5

1.20-1.70m

B

C44986

Sample Description


0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT


SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

9

21

15

0

0


Sieving Method


Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

0.86

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

100

100

100

100

100

100

99

96

-

91

-

85

83

81

-

79

-

75

-

64

47

23

9

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette


22.72

SAND

GRAVEL

COBBLES

BOULDERS

Classification

55

CLAY

SILT



Project:



Sample Depth

Sample Type

Sample Ref

TP5

0.50m

B

C44967

Sample Description

Brown slightly sandy slightly gravelly CLAY

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT


SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

43

16

2

0

0


Sieving Method


Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

4.40

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

100

100

100

100

100

100

99

99

-

98

-

98

97

97

-

93

-

85

-

82

57

46

43

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette


Not Available

SAND

GRAVEL

COBBLES

BOULDERS

Classification

39

CLAY

SILT



Project:



Sample Depth

Sample Type

Sample Ref

TP5

0.75m

B

C44966

Sample Description

Brown gravelly slightly sandy gravelly CLAY.

0

10

20

30

40

50

60

70

80

90

100

0.001 0.01 0.1 1 10 100 1000Particle Size (mm)

% F

iner

CLAY

Fine Medium Coarse

SILT


SAND

Fine Medium Coarse

Gravel

Cobbles Boulders

% of each

16

18

36

0

0


Sieving Method


Method

Pre-treated

with

% loss on

Pre-treatment

Particle

Density

Wet sieve

Hydrogen

Peroxide

0.21

2.65

(Assumed)

125mm

100mm

75mm

63mm

50mm

37.5mm

28mm

20mm

14mm

10mm

6.3mm

5mm

3.35mm

2mm

1.18mm

600 m

425 m

300 m

212 m

150 m

75 m

63 m

20 m

6 m

2 m

µ

100

100

100

100

100

86

-

75

72

70

-

66

-

64

63

62

-

59

-

52

-

46

32

21

16

µ

µ

µ

µ

µ

µ

µ

µ

µ

Pipette


Not Available

SAND

GRAVEL

COBBLES

BOULDERS

Classification

30

CLAY

SILT


LABORATORY RESULTS - MCV, Compaction, CBR

Project Project No:

Sample


Depth)

Sample


Ref

m

(Specimen

Compaction CBR

MCV Typeγb

BottomType w

w

%

CBR

%

Top

w

%

CBR

%Mg/m3

w

MCV

ddρ γ

Mg/m3

(Opt) (Max)

% % Mg/m3

BH5 B C449861.20-

1.70

(1.20-

1.70)


gravelly CLAY

2.5kg (10)

12*

3.5

6.6

9.2

16

2.65a

2.11

*2.11

1.86

1.95

2.05

2.10

1.89

(1.90)

*1.89

1.80

1.83

1.88

1.82

2.5kg 23 12 20 12

TP5 B C449670.50

(0.50)

Brown slightly sandy slightly

gravelly CLAY

2.5kg (23)

32*

14

19

29

12

26

2.65a

1.84

*1.84

1.66

1.74

1.86

1.59

1.87

1.39

(1.50)

*1.39

1.46

1.46

1.45

1.42

1.49

2.5kg 5.7 33 5.2 31

TP5 B C449660.75

(0.75)

Brown gravelly slightly sandy

gravelly CLAY.

2.5kg (18)

27*

8.8

13

19

23

2.65a

1.90

*1.90

1.60

1.75

1.97

1.96

1.50

(1.66)

*1.50

1.47

1.55

1.65

1.59

2.5kg 2.8 26 2.6 28

TP6 B C449650.75

(0.75)

Light brown clayey GRAVEL with

cobbles

2.5kg (13)

11*

8.8

13

14

26

2.95a

2.02

*2.02

1.99

2.13

2.18

2.07

1.82

(1.90)

*1.83

1.83

1.89

1.91

1.64

2.5kg 24 11 27 11

Remarks Particle Density - a=assumed, m=measured

Tests performed in accordance with BS 1377: 1990

* = at natural moisture content

LABORATORY RESULTS -

Project:



Sample Depth

Sample Type

Sample Ref

BH5

1.20-1.70m

B

C44986

Compaction

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

0 5 10 15 20 25 30 35 40 45 50

Moisture Content (%)

Dry

Density

(M

g/m

^3)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

CB

R %

2.5kg rammer at natural moisture content

2.5kg rammer�

�

�

Optimum Moisture Content

��

CBR % Top

CBR % Bottom

Test performed in accordance with BS 1377: Part 4: 1990Remarks



Maximum Dry Density

Gravel retained on

20mm sieve

Particle Density10

1.90

0

1

2.65

37.5mm sieve

Preparation 2.5kgMg/m3

%

%

Description

21/09/2010

(Assumed)


Project:



Sample Depth

Sample Type

Sample Ref

TP5

0.50m

B

C44967

Compaction

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

0 5 10 15 20 25 30 35 40 45 50


Dry

Density

(M

g/m

^3)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

CB

R %


2.5kg rammer�

�

�


��

CBR % Top

CBR % Bottom


Brown slightly sandy slightly gravelly CLAY


Maximum Dry Density

Gravel retained on

20mm sieve

Particle Density23

1.50

0

0

2.65

37.5mm sieve


%

%

Description

21/09/2010

(Assumed)


Project:



Sample Depth

Sample Type

Sample Ref

TP5

0.75m

B

C44966

Compaction

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

0 5 10 15 20 25 30 35 40 45 50


Dry

Density

(M

g/m

^3)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

CB

R %


2.5kg rammer�

�

�


��

CBR % Top

CBR % Bottom


Brown gravelly slightly sandy gravelly CLAY.


Maximum Dry Density

Gravel retained on

20mm sieve

Particle Density18

1.66

1

6

2.65

37.5mm sieve


%

%

Description

21/09/2010

(Assumed)


Project:



Sample Depth

Sample Type

Sample Ref

TP6

0.75m

B

C44965

Compaction

1.00

1.10

1.20

1.30

1.40

1.50

1.60

1.70

1.80

1.90

2.00

2.10

2.20

2.30

2.40

2.50

0 5 10 15 20 25 30 35 40 45 50


Dry

Density

(M

g/m

^3)

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

CB

R %


2.5kg rammer�

�

�


��

CBR % Top

CBR % Bottom


Light brown clayey GRAVEL with cobbles


Maximum Dry Density

Gravel retained on

20mm sieve

Particle Density13

1.90

17

29

2.95

37.5mm sieve


%

%

Description

21/09/2010

(Assumed)

LABORATORY RESULTS - Test Remarks

Project Project No:

Sample

Hole Depth Type

Depth)

Sample


Ref

m

(SpecimenLaboratory Remark

BH4 U C449923.20-

3.55

(3.20-

3.55)

Quick Undrained Triaxial Test - UT = Sample too disturbed

Remarks

13

APPENDIX 13

Laboratory Test Results - Contamination (Soil)

2139 Certificate Number: 10-41258Date: 16/09/2010

Client: Geotechnics LTD203 Torrington AvenueTile HillCoventryCV4 9AP

Our Reference: 10-41258

Client Reference: PC104350

Contract Title: Buccleuch Academy, Kettering

Description: 10 soil samples

Date Received: 08/09/2010

Date Started: 08/09/2010

Date Completed: 16/09/2010

Test Procedures: Identified by prefix DETSn, details available upon request.

Notes: Observations and interpretations are outside the scope of UKAS accreditation

Certificate of Analysis

Notes: Observations and interpretations are outside the scope of UKAS accreditation* denotes test not included in laboratory scope of accreditation# denotes test that holds MCERT accreditation$ denotes tests completed by an approved subcontractorI/S denotes insufficient sample to carry out testN/S denotes that the sample is not suitable for testingDETSM denotes tests carried out by DETS Midlands laboratorySolid samples will be disposed 1 month and liquids 2 weeksafter the date of issue of this test certificateAsbestos subsamples will be kept for 6 months

Approved By:

Authorised Signatories: Rob BrownBusiness Manager

This certificate is issued in accordance with the accreditation requirements of the United Kingdom Accreditation Service. The results reported herein relate only to the material supplied to the laboratory. This certificate shall not be reproduced except in full, without the prior written approval of the

laboratory.

Derwentside Environmental Testing Services LimitedUnit 2, Park Road Industrial Estate South, Consett, Co Durham, DH8 5PY

Tel: 01207 582333 • Fax 01207 582444 • email: [email protected] • www.dets.co.uk Page 1 of 7

Our Ref: 10-41258

Client Ref: PC104350

Sample ID Depth DETS Ref Matrix Description Date Sampled Time Sampled Preservation Analysis Complete

BH1 0.30 279891 brown gravelly sandy CLAY odd rootlets Not Provided Not Provided None 16/09/2010

BH3 0.70 279892 dark brown gravelly sandy CLAY Not Provided Not Provided None 16/09/2010

BH4 0.40 279893 dark brown gravelly sandy CLAY odd rootlets Not Provided Not Provided None 16/09/2010

BH5 1.80 279894 light brown gravelly sandy CLAY odd rootlets Not Provided Not Provided None 16/09/2010

BH6 0.40 279895 dark brown gravelly sandy CLAY Not Provided Not Provided None 16/09/2010

TP1 0.30 279896 dark brown gravelly sandy CLAY odd rootlets Not Provided Not Provided None 16/09/2010






Sample Details

Derwentside Environmental Testing Services Ltd Page 2 of 7

Soil SamplesOur Ref: 10-41258Client Ref: PC104350

279891 279892 279893 279894 279895BH1 BH3 BH4 BH5 BH60.30 0.70 0.40 1.80 0.40

Test Units DETSxxArsenic mg/kg DETS 042# 14 18 15 5.5 16Cadmium mg/kg DETS 042# 1.1 1.0 1.0 0.4 1.0Chromium mg/kg DETS 042# 87 48 54 18 54Copper mg/kg DETS 042# 19 17 19 6 19Lead mg/kg DETS 042# 18 15 17 6 17Manganese mg/kg DETS 042# 1200 370 570 490 530Mercury mg/kg DETS 081# < 0.05 < 0.05 < 0.05 < 0.05 < 0.05Nickel mg/kg DETS 042# 57 37 38 12 38Selenium mg/kg DETS 042# < 0.5 < 0.5 < 0.5 < 0.5 < 0.5Zinc mg/kg DETS 042# 81 69 82 28 73Vanadium mg/kg DETS 042# 64 60 75 28 76Chloride Aqueous Extract mg/l DETS 055Nitrate Aqueous Extract as NO3 mg/l DETS 055Magnesium Aqueous Extract mg/l DETS 076*Organic matter % DETS 002# 2.2 0.8 1.4 0.2 1.0Total Sulphate as SO4 % DETS 075#Sulphate Aqueous Extract as SO4 mg/l DETS 076#Total Sulphur as S % DETS 064Total Organic Carbon % DETS 002 1.3 0.5 0.8 0.1 0.6pH DETS 008# 7.6 8.0 7.9 8.1 7.9PAH mg/kg DETS 050 < 1.6 < 1.6 < 1.6 < 1.6 < 1.6EPH (C5-C10) mg/kg DETS 051 < 10 < 10 < 10 < 10 < 10EPH (C10-C40) mg/kg DETS 051# 11 < 10 < 10 < 10 12Phenol - Monohydric mg/kg DETS 067# < 0.3 < 0.3 < 0.3 < 0.3 < 0.3Ammonia Aqueous Extract as N mg/l DETS 019

Sample Type

Summary of Chemical Analysis


Lab No.Sample ID

DepthSample Ref


Soil SamplesOur Ref: 10-41258Client Ref: PC104350

Test Units DETSxxArsenic mg/kg DETS 042#Cadmium mg/kg DETS 042#Chromium mg/kg DETS 042#Copper mg/kg DETS 042#Lead mg/kg DETS 042#Manganese mg/kg DETS 042#Mercury mg/kg DETS 081#Nickel mg/kg DETS 042#Selenium mg/kg DETS 042#Zinc mg/kg DETS 042#Vanadium mg/kg DETS 042#Chloride Aqueous Extract mg/l DETS 055Nitrate Aqueous Extract as NO3 mg/l DETS 055Magnesium Aqueous Extract mg/l DETS 076*Organic matter % DETS 002#Total Sulphate as SO4 % DETS 075#Sulphate Aqueous Extract as SO4 mg/l DETS 076#Total Sulphur as S % DETS 064Total Organic Carbon % DETS 002pH DETS 008#PAH mg/kg DETS 050EPH (C5-C10) mg/kg DETS 051EPH (C10-C40) mg/kg DETS 051#Phenol - Monohydric mg/kg DETS 067#Ammonia Aqueous Extract as N mg/l DETS 019

Sample Type

Summary of Chemical Analysis


Lab No.Sample ID

DepthSample Ref

279896 279897 279898 279899 279900TP1 TP2 TP3 TP4 TP50.30 0.20 0.20 0.80 1.25

13 17 14 13 121.0 1.1 0.9 0.8 0.836 50 38 40 4519 28 19 15 1526 45 31 14 12

900 900 710 340 420< 0.05 0.06 0.06 < 0.05 < 0.05

23 31 25 29 29< 0.5 < 0.5 < 0.5 < 0.5 < 0.5

84 130 82 64 6158 62 59 56 62

111.1

< 104.0 5.2 2.8 1.2 1.1

0.0838

0.072.3 3.0 1.6 0.7 0.67.8 7.7 7.7 8.2 8.1

< 1.6 < 1.6 < 1.6 < 1.6 < 1.6< 10 < 10 < 10 < 10 < 10

18 19 < 10 < 10 < 10< 0.3 < 0.3 < 0.3 < 0.3 < 0.3

< 10


Appendix A - Details of Analysis

Method details are shown only for those determinants listed in Annex A of the MCERTS standard. Anything not included on this list falls outside the scope of MCERTS.No Recovery Factors are used in the determination of results. Results reported assume 100% recoveryFull method statements are available on request.

Method Units Sub-Contracted UKAS MCERTS

DETS 002 Organic Matter % Yes Yes

DETS 003 Loss on Ignition % Yes Yes

DETS 004 Total Sulphate % Yes Yes

DETS 075 Total Sulphate % Yes Yes

DETS 004 Water Soluble Sulphate mg/l Yes Yes

DETS 076 Water Soluble Sulphate mg/l Yes Yes

DETS 006 Chloride mg/kg Yes Yes

DETS 008 pH pH Units Yes Yes

DETS 042 Selenium mg/kg Yes Yes

DETS 019 Ammonia mg/kg Yes Yes

DETS 020 Boron (Water Soluble) mg/kg Yes Yes

DETS 024 Sulphide mg/kg Yes Yes

DETS 042 Antimony mg/kg No No

DETS 042 Arsenic mg/kg Yes Yes

DETS 042 Barium mg/kg Yes Yes

DET S 042 Beryllium mg/kg Yes Yes

DETS 042 Cadmium mg/kg Yes Yes

10.00 Air Dried No

10.00 Air Dried No

0.01 Air Dried No

0.20

1.50

0.20

0.10 Air Dried

0.01

0.10

0.50

0.02

0.20

10.00

1.00

Sample Preparation

Air Dried

Air Dried

Air Dried

Air Dried

Name of Parameter Limit of Detection

0.01

0.01

0.01

Air Dried

Air Dried

Air Dried

Air Dried

Air Dried

Air Dried

Air Dried

Air Dried

No

No

No

No

No

No

No

No

Air Dried

No

No

No

No

No

No




Method Units Sub-Contracted UKAS MCERTSSample PreparationName of Parameter Limit of Detection

DETS 042 Cobalt mg/kg Yes Yes

DETS 042 Copper mg/kg Yes Yes

DETS 042 Chromium mg/kg Yes Yes

DETS 042 Iron mg/kg Yes No

DETS 042 Lead mg/kg Yes Yes

DETS 042 Manganese mg/kg Yes Yes

DETS 081 Mercury mg/kg Yes Yes

DETS 042 Molybdenum mg/kg Yes Yes

DETS 042 Nickel mg/kg Yes Yes

DETS 042 Thallium mg/kg No No

DETS 042 Vanadium mg/kg Yes Yes

DETS 042 Zinc mg/kg Yes Yes

DETS 049 Sulphur (Free) mg/kg Yes Yes

DETS 050 PAH mg/kg Yes No

DETS 051 TPH (C10 - C40) mg/kg Yes Yes

DETS 052 PCB mg/kg Yes Yes

20.00 Air Dried No

Air Dried No

0.30 Air Dried

0.20 Air Dried No

0.05 Air Dried No

0.40 Air Dried No

No

1.00

0.70

0.20

Air Dried

0.15

Air Dried

Air Dried

No

No

No

1.00 Air Dried No

0.80 Air Dried No

1.00 Air Dried No

0.50 As Received No

0.10 As Received No

20.00 As Received No

0.01 As Received No




Method Units Sub-Contracted UKAS MCERTSSample PreparationName of Parameter Limit of Detection

DETS 062 Benzene mg/kg Yes Yes

DETS 062 Toluene mg/kg Yes Yes

DETS 062 Ethylbenzne mg/kg Yes Yes

DETS 062 Xylene mg/kg Yes Yes

DETS 067 Phenol - Monohydric mg/kg Yes Yes

DETS 067 Easily Liberatable Cyanide mg/kg Yes Yes

DETS 067 Complex Cyanide mg/kg Yes No

DETS 067 Total Cyanide mg/kg Yes Yes

DETS 067 Thiocyanate mg/kg Yes Yes

DETS 068 VOC mg/kg No No

0.01 As Received No

0.01 As Received No

0.01 As Received No

0.01 As Received No

0.3 Air Dried No

0.1 Air Dried No

0.30 Air Dried No

0.01 As Received No

0.40 Air Dried No

0.6 Air Dried No


14

APPENDIX 14

Laboratory Test Results - Contamination (Groundwater)

15

APPENDIX 15

Sections

16

APPENDIX 16

Material Property Plots


Job No PC104350

Date 23/09/2010

Figure 1.1

BUCCLEUCH ACADEMY, KETTERING

Plot of SPT - Depth Profile

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

0 10 20 30 40 50 60

SPT 'N' ValueD

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 1.2


Plot of SPT - Depth Profile

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

20.00

0 10 20 30 40 50 60

SPT 'N' ValueD

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 2.1


Plot of Moisture Content - Depth Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

0 10 20 30 40 50 60

Moisture Content %D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 2.2



0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

0 10 20 30 40 50 60

Moisture Content %D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 2.3



0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

0 10 20 30 40 50 60

Moisture Content %D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 3.1


Plot of Bulk Density - Depth Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

1.40 1.50 1.60 1.70 1.80 1.90 2.00 2.10 2.20 2.30 2.40

Bulk Density (Mg/m3)D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 3.2


Plot of Bulk Density - Depth Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

1.40 1.50 1.60 1.70 1.80 1.90 2.00 2.10 2.20 2.30 2.40

Bulk Density (Mg/m3)D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 4.1


Plot of Shear Strength - Depth Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

0 50 100 150 200 250 300

Shear Strength (kPa)D

ep

th (

m b

gl)


Job No PC104350

Date 23/09/2010

Figure 4.2


Plot of Shear Strength - Depth Profile

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

9.00

10.00

11.00

12.00

0 50 100 150 200 250 300

Shear Strength (kPa)D

ep

th (

m b

gl)

Soil Type Plasticity Characteristics

C Clay L Low

I Intermediate

M Silt H High

V Very High

E Extremely High


Job No PC104350

Date 23/09/2010

Figure 5.1


Plasticity Chart

0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Liquid Limit %

Pla

sti

cit

y I

nd

ex %

CH

CV

CE

MLMI

MV

ME

CL

CI

Low Medium High Very High Extremely High

Plasticity


C Clay L Low

I Intermediate

M Silt H High

V Very High

E Extremely High


Job No PC104350

Date 23/09/2010

Figure 5.2


Plasticity Chart

0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Liquid Limit %

Pla

sti

cit

y I

nd

ex %

CH

CV

CE

MLMI

MV

ME

CL

CI


Plasticity


C Clay L Low

I Intermediate

M Silt H High

V Very High

E Extremely High


Job No PC104350

Date 23/09/2010

Figure 5.3


Plasticity Chart

0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Liquid Limit %

Pla

sti

cit

y I

nd

ex %

CH

CV

CE

MLMI

MV

ME

CL

CI


Plasticity


Job No PC104350

Date 23/09/2010

Figure 6.1


Summary of Particle Size Distribution

Analyses

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

0.001 0.010 0.100 1.000 10.000 100.000

Particle Size (mm)

% F

ine

r

BH1 0.40m B BH3 1.60m B BH5 0.30m B BH5 1.20m B

GravelSandSiltClay


Job No PC104350

Date 23/09/2010

Figure 6.2


Summary of Particle Size Distribution

Analyses

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

0.001 0.010 0.100 1.000 10.000 100.000

Particle Size (mm)

% F

ine

r

TP5 0.75m B TP5 0.50m B

GravelSandSiltClay

17

APPENDIX 17

Existing Soakaway Inspection Report

Your Ref : Kettering Beccleuch Academy Our Ref : CGS/PC104350 Date : 15 September 2010

Willmott Dixon Construction Limited Chantry House High Street Coleshill Birmingham B46 3BP For the attention of Mr Chris Kinman Dear Sirs Re : Soakaway inspection visit of 19th August 2010, Montagu School, Kettering.

Please find enclosed a selection of photographs taken on 19th August 2010 at Montagu School, Kettering and our comments. Geotechnics Limited attended the site on the above date in the presence of Mr. Carl Hanson of Cox Turner Morse and investigated all of the noted soakaways on the Proposed Surface Water Drainage Strategy Map produced by Mott MacDonald (Ref: MMD-258960-C-00-XX-SK-002) as enclosed in the site flood risk assessment report provided by yourselves. The soakaways have been numbered SA1-SA6 clockwise from the site entrance for ease of reference and to record the order in which they were investigated. These locations are marked on the enclosed sketch plan based on the above noted Mott Macdonald document. Generally it would appear that there are two sets of installations and possibly two strategies of installation. SA1, SA3 and SA4 appear to be of an older age, probably dating from the first phase of the school. These soakaways contain three linked oblong chambers generally 1.2m by 1.5m, though in the case of SA1 the eastern chamber may possibly be several meters wide as this location was heavily obscured by silt. Generally, one of the three chambers contains a borehole installation. We presume the boreholes pass through the clay and into the underlying Lincolnshire Limestone. In all three cases, the bases appeared to be heavily silted to varying degrees and the depths from the tops of the covers to the silt are noted in Table 1. In the case of SA4, the eastern cover was buried below ground level and therefore direct access was not possible and the presence of a borehole within the eastern chamber has been inferred. The second set of soakaways (SA2, SA5 and SA6) appears to date from either the time of the building of the Sports Hall or the English Block. These are more recent installations and comprise a variable number of deep circular chambers approximately 3-4m in diameter, one of which may contain a borehole as above. SA2 comprises three chambers in a J shape, SA5 comprises two in a line and SA6 is a single chamber. In SA6 no evidence of a borehole was noted, though access was limited and the location appeared heavily silted and therefore the borehole may have been buried. Alternatively, given that this location only appears to take water from one half of the English Block roof, it may be that no borehole is in fact present.

Cont.

CGS/PC104350/2 With reference to carrying out soakage tests in these soakaways, access to most locations should be relatively easy for most mobile equipment. However, such tests may include the transport of large volumes of water and/or relatively heavy equipment over grassed areas. As such it is probable that any such works may involve a degree of disturbance to some grassed areas, with possible re-instatement implications depending on the method, precise access routes and the weather/soil conditions at the time of the works. A fire hydrant location suitable for the supply of water on site was noted to us by the facilities manager in front of the main entrance to reception. However, the use of this standpipe may require a licence. Whilst the condition of the soakaways appeared generally good during this limited investigation, it is recommended that further more detailed investigation of the depth of the silt, the exact dimensions of the chambers and their connectivity as well as a more detailed inspection of the interiors if they are to be retained. This work would need to be undertaken by competent persons suitably trained in confined space works with appropriate safety equipment, procedures and method statements. As noted in our meeting of the 16th August 2010, Geotechnics Limited does not currently employ any appropriately trained or certified staff capable of undertaking such works. The relatively recent age of some of the soakaways may indicate that plans, manuals and details may still be available from the local Council or may be held on site by Mr Richard Adshead the Facilities Manager. We understand that Mr. Carl Hanson of Cox Turner Morse will be undertaking to locate and retrieve such information if possible. Table 1:

Location Chamber Dimensions (m)*

Depth to base(m Bgl)

Borehole Notes

SA1 (East of Sports Hall) Eastern 1.2 x 2.0 1.9

Central 1.2 x 1.5 1.9

Western 1.2 x 1.5 2.3 Yes

SA2 (West of Sports Hall) Northern 3.5 Depth to Water 5.4m

Central 3.5 Depth to Water 5.4m

Western 3.5 5.4 Yes

SA3 (Far West of Hall) Western 1.2 x 1.5 4.4 Damp Base

Central 1.2 x 1.5 4.5

Eastern 1.2 x 1.5 4.6 Yes

SA4 (SW of Humanities) Western 1.2 x 1.5 4.9

Central 1.2 x 1.5 5.2

Eastern No Access No Access Possibly Inferred

SA5 (West of English) Eastern 3.5 4.2 Damp base

Western 3.5 4.4 Yes

SA6 (North of English) Single 3.5 3.4 Not known if Borehole present

* Dimensions Estimated from Surface. Single value indicates estimated circular chamber diameter.

Cont.

CGS/PC104350/3 We trust these comments and the enclosed photographs are sufficient to your needs, but if you require any additional information or clarification, please do not hesitate to contact us. Yours faithfully C Swainston For and on behalf of GEOTECHNICS LIMITED

Enc Sketch Plan based on Mott MacDonald Drawing Number: MMD-258960-C-00-XX-SK-002 Site Photographs

Location: Montagu School, Kettering

Project Number: PC104350

Date: August 2010

Sketch of Soakaway Locations at Montagu School, Kettering as of 19th August 2010.

Based on Mott MacDonald Plan (Ref: MMD-258960-C-00-XX-SK-002)

SA2 SA3

SA1

SA4

SA5

SA6

Location of Soakaway east of Sports Hall (SA1) SA1 Eastern Chamber

SA1 Central Chamber SA1 Western Chamber with borehole

PHOTOGRAPHS



SA2 Northern Chamber SA2 Southern Chamber

Soakaway West of Sports Hall with Borehole (SA2)

PHOTOGRAPHS



Location of Soakaway Far West of Sports Hall (SA3) SA3 Western Chamber

SA3 Central Chamber SA3 Eastern Chamber with Borehole

PHOTOGRAPHS



Location of Soakaway south of Humanities Block (SA4) SA4 Western Chamber

SA4 Central Chamber

PHOTOGRAPHS



Location of Soakaway west of Former English Block (SA5) SA5 Eastern Chamber

SA5 Western Chamber with Borehole

PHOTOGRAPHS



Location of Soakaway north of Former English Block (SA6) SA6 No borehole visible

PHOTOGRAPHS



18

APPENDIX 18

Investigation Techniques and General Notes

Geotechnics Limited © The Geotechnical Centre, 203 Torrington Avenue, Tile Hill, Coventry. CV4 9AP

INVESTIGATION TECHNIQUES INTRODUCTION The following brief review of Ground Investigation techniques, generally used as part of most Site Investigations in the UK, summarises their methodology, advantages and limitations. Detailed descriptions of the techniques are available and can be provided on request. This review should be read in conjunction with the accompanying General Notes. TRIAL PITS The trial pit is amongst the most simple yet effective means of identifying shallow ground conditions on a site. Its advantages include simplicity, speed, potential accuracy and cost-effectiveness. The trial pit is most commonly formed using a backacting excavator which can typically determine ground conditions to some 4 metres below ground level. Hand excavation is often used to locate, expose and detail existing foundations, features or services. In general, it is difficult to extend pits significantly below the water table in predominantly granular soils, where flows can cause instability. Unless otherwise stated, the trial pits will not have been provided with temporary side support during their construction. Under such circumstances ground conditions to some 1.20 metres can be closely inspected, subject to stability assessment, but below this depth, entrance into the pit is not permitted in the absence of shoring and hence observations will have been made from ground surface and samples taken from the excavator bucket. Trends in strata type, level and thickness can be determined, shear surfaces identified and the behaviour of plant, excavation sides and excavated materials can be related to the construction process. They are particularly valuable in land slip investigations. Some types of insitu test can be undertaken in such pits and large disturbed or block samples obtained. CABLE PERCUSSION BORING The light Cable Percussion technique of soft ground boring, typically at a diameter of 150mm, is a well established simple and flexible method of boring vertical holes and generally allows data to be obtained in respect of strata conditions other than rock. A tubular cutter (for cohesive soils) or shell with a flap valve (for granular soils) is repeatedly lifted and dropped using a winch and rope operating from an “A” frame. Soil which enters these tools is regularly removed and either sampled for subsequent examination or test, or laid to one side for backfilling. Steel casing will have been used to prevent collapse of the borehole sides where necessary. A degree of disturbance of soil and mixing of layers is inevitable and the presence of very thin layers of different soils within a particular stratum may not be identified. Changes in strata type can only be detected on recognition of a change in soil samples at surface, after the interface has been passed. For the foregoing reasons, depth measurements should not be considered to be more accurate than 0.10 metre. In cohesive soils cylindrical samples are retrieved by driving or pushing in 100mm nominal diameter tubes. In soft soils, piston sampling or vane testing may be undertaken. In granular soils and often in cohesive materials, insitu Standard Penetration Tests (SPT’s) are performed. The SPT records the number of standard blows required to drive a 50mm diameter open or cone ended probe for 300mm after an initial 150mm penetration. A modified method of recording is used in more dense strata. Small disturbed samples are obtained throughout. The technique can determine ground conditions to depths in excess of 30 metres under suitable circumstances and usually causes less surface disturbance than trial pitting. ROTARY DRILLING Rotary Drilling to produce cores by rotating an annular diamond-impregnated tube or barrel into the ground is the technique most appropriate to the forming of site investigation boreholes through rock or other hard strata. It has the advantage of being able to be used vertically or at an angle. Core diameters of less than 100mm are most common for site investigation purposes. Core is normally retrieved in plastic lining tubes. A flushing fluid such as air, water or foam is used to cool the bit and carry cuttings to the surface. Examination of cores allows detailed rock description and generally enables angled discontinuity surfaces to be observed. However, vertical holes do not necessarily reveal the presence of vertical or near-vertical fissures or joint discontinuities. The core type and/or techniques used. Where open hole rotary drilling is employed, descriptions of strata result from examination at surface of small particles ejected from the borehole in the flushing medium. In consequence, no indication of fissuring, bedding, consistency or degree of weathering can be obtained. Small scale plant can be used for auger drilling to limited depths where access is constrained. Depths in excess of 60 metres can be achieved under suitable circumstances using rotary techniques, with minimal surface disturbance.

WINDOW SAMPLING This technique involves the driving of an open-ended tube into the ground and retrieval of the soil which enters the tube. The term “window sample” arose from the original device which had a “window” or slot cut into the side of the tube through which samples were taken. This has now been superseded by the use of a thin-walled plastic liner within a sampler which has a solid wall. Diameters range from 36 to 86mm. Such samples can be used for qualitative logging, selection of samples for classification and chemical analysis and for obtaining a rudimentary assessment of strength. Driving devices can be hand-held or machine mounted and the drive tubes are typically in 1m lengths. The hole formed is not cased, however, and hence the success of this technique is limited when soils and groundwater conditions are such that the sides of the hole collapse on withdrawal of the sampler. Obstructions within the ground, the density of the material or its strength can also limit the depth and rate of penetration of this light-weight investigation technique. Nevertheless, it is a valuable tool where access is constrained such as within buildings or on embankments. Depths of up to 8m can be achieved in suitable circumstances but depths of 4m to 6m are more common. EXPLORATORY HOLE RECORDS The data obtained by these techniques are generally presented on Trial Pit, Borehole, Drillhole or Window Sample Records. The descriptions of strata result from information gathered from a number of sources which may include published geological data, preliminary field observations and descriptions, insitu test results, laboratory test results and specimen descriptions. A key to the symbols and abbreviations used accompanies the records. The descriptions on the exploratory hole records accommodate but may not necessarily be identical to those on any preliminary records or the laboratory summaries. The records show ground conditions at the exploratory hole locations. The degree to which they can be used to represent conditions between or beyond such holes, however, is a matter for geological interpretation rather than factual reporting and the associated uncertainties must be recognised. DYNAMIC PROBING This technique typically measures the number of blows of a standard weight falling over a standard height to advance a cone-ended rod over sequential standard distances (typically 100mm). Some devices measure the penetration of the probe per standard blow. It is essentially a profiling tool and is best used in conjunction with other investigation techniques where site-specific correlation can be used to delineate the distribution of soft or loose soils or the upper horizon of a dense or strong layer such as rock. Both machine-driven and hand-driven equipment is available, the selection depending upon access restrictions and the depth of penetration required. It is particularly useful where access for larger equipment is not available, disturbance is to be minimised or where there are cost constraints. No samples are recovered and some techniques leave a sacrificial cone head in the ground. As with other lightweight techniques, progress is limited in strong or dense soils. The results are presented both numerically and graphically. Depths of up to 10m are commonly achieved in suitable circumstances. The hand-driven DCP probing device has been calibrated by the TRL to provide a profile of CBR values over a range of depths of up to 1.50m. INSTRUMENTATION The most common form of instrument used in site investigation is either the standpipe or else the standpipe piezometer which can be installed in investigation holes. They are used to facilitate monitoring of groundwater levels and water sampling over a period of time following site work. Normally a standpipe would be formed using rigid plastic tubing which has been perforated or slotted over much of its length whilst a standpipe piezometer would have a filter tip which would be placed at a selected level and the hole sealed above and sometimes below to isolate the zone of interest. Groundwater levels are determined using an electronic “dipmeter” to measure the depth to the water surface from ground level. Piezometers can also be used to measure permeability. They are simple and inexpensive instruments for long term monitoring but response times can limit their use in tidal areas and access to the ground surface at each instrument is necessary. Remote reading requires more sophisticated hydraulic, electronic or pneumatic equipment. Settlement can be monitored using surface or buried target plates whilst lateral movement over a range of depths is monitored using slip indicator or inclinometer equipment.

Geotechnics Limited © The Geotechnical Centre, 203 Torrington Avenue, Tile Hill, Coventry. CV4 9AP

GENERAL NOTES 1. The report is prepared for the exclusive use of the Client named in the

document and copyright subsists with Geotechnics Limited. Prior written

permission must be obtained to reproduce all or part of the report. It is

prepared on the understanding that its contents are only disclosed to

parties directly involved in the current investigation, preparation and

development of the site.

2. Further copies may be obtained with the Client's written permission,

from Geotechnics Limited with whom the master copy of the document

will be retained.

3. The report and/or opinion is prepared for the specific purpose stated in

the document and in relation to the nature and extent of proposals

made available to Geotechnics Limited at that time. Re-consideration

will be necessary should those details change. The recommendations

should not be used for other schemes on or adjacent to the site without

further reference to Geotechnics Limited.

4. The assessment of the significance of the factual data, where called for,

is provided to assist the Client and his Engineer and/or Advisers in the

preparation of their designs.

5. The report is based on the ground conditions encountered in the

exploratory holes together with the results of field and laboratory testing

in the context of the proposed development. The data from any

commissioned desk study and site reconnaissance are also drawn upon.

There may be special conditions appertaining to the site, however, which

are not revealed by the investigation and which may not be taken into

account in the report.

6. Methods of construction and/or design other than those proposed by the

designers or referred to in the report may require consideration during

the evolution of the proposals and further assessment of the

geotechnical and any geoenvironmental data would be required to

provide discussion and evaluations appropriate to these methods.

7. The accuracy of results reported depends upon the technique of

measurement, investigation and test used and these values should not be

regarded necessarily as characteristics of the strata as a whole (see

accompanying notes on Investigation Techniques). Where such

measurements are critical, the technique of investigation will need to be

reviewed and supplementary investigation undertaken in accordance

with the advice of the Company where necessary.

8. The samples selected for laboratory test are prepared and tested in

accordance with the relevant Clauses of BS 1377 Parts 1 to 8, where

appropriate, in Geotechnics Limited’s UKAS accredited Laboratory,

where possible. A list of tests is given.

9. Tests requiring the use of another laboratory having UKAS accreditation

where possible are identified.

10. Any unavoidable variations from specified procedures are identified in

the report.

11. Specimens are cut vertically, where this is relevant and can be identified,

unless otherwise stated.

12. All the data required by the test procedures are recorded on

individual test sheets but the results in the report are presented in

summary form to aid understanding and assimilation for design

purposes. Where all details are required, these can be made

available.

13. Whilst the report may express an opinion on possible

configurations of strata between or beyond exploratory holes, or on

the possible presence of features based on either visual, verbal,

written, cartographical, photographic or published evidence, this is

for guidance only and no liability can be accepted for its accuracy.

14. Classification of materials as Made Ground is based on the

inspection of retrieved samples or exposed excavations. Where it is obvious that foreign matter such as paper, plastic or metal is present, classification is clear. Frequently, however, for fill materials that arise from the adjacent ground or from the backfilling of excavations, their visual characteristics can closely resemble those of undisturbed ground. Other evidence such as site history, exploratory hole location or other tests may need to be drawn upon to provide clarification. For these reasons, classification of soils on the exploratory hole records as either Made Ground or naturally occurring strata, the boundary between them and any interpretation that this gives rise to should be regarded as provisional and subject to re-evaluation in the light of further data.

15. The classification of materials as Topsoil is generally based on

visual description and should not be interpreted to mean that the material so described complies with the criteria for Topsoil used in BS 3882 (2007). Specific testing would be necessary where such definition is a requirement.

16. Ground conditions should be monitored during the construction of

the works and the report should be re-evaluated in the light of

these data by the supervising geotechnical engineers.

17. Any comments on groundwater conditions are based on

observations made at the time of the investigation, unless specifically stated otherwise. It should be noted, however, that the observations are subject to the method and speed of boring, drilling or excavation and that groundwater levels will vary due to seasonal or other effects.

18. Any bearing capacities for conventional spread foundations which

are given in the report and interpreted from the investigation are for bases at a minimum depth of 1m below finished ground level in naturally occurring strata and at broadly similar levels throughout individual structures, unless otherwise stated. The foundations should be designed in accordance with the good practice embodied in BS 8004:1986 - Foundations, supplemented for housing by NHBC Standards. Foundation design is an iterative process and bearing pressures may need adjustment or other measures may need to be taken in the context of final layouts and levels prior to finalisation of proposals.

19. Unless specifically stated, the investigation does not take account

of the possible effects of mineral extraction or of gases from fill or

natural sources within, below or outside the site.

20. The costs or economic viability of the proposals referred to in the

report, or of the solutions put forward to any problems

encountered, will depend on very many factors in addition to

geotechnical or geoenvironmental considerations and hence their

evaluation is outside the scope of the report.

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