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Client: EDF Energy NetworksContractor: Laing O’Rourke InfrastructureProducer: O’Keefe Utilities Processing Facilities: Silvertown E16 and Atlas Road NW10 Product: Structural Material for Reinstatement

The product name and its origins

The recycled material we produce is known by its trade namePAVIMENTUM and is abbreviated to PV1. The name originatesfrom the material that was used by the Romans for theconstruction of their roads over 2,000 years ago.

The roads were built with pieces of crushed stone, lime, flint,tile, and other materials which were set in a bed of ashes orcement and consolidated by beating down with a rammer. Theearth bed/middle level of their road construction was known as‘Pavimentum’.

Why use an Alternative Reinstatement Material?

The release of the Advice note 2009/1 in advance of theamended Appendix A9 of the HAUC New Roads and StreetWorks Act 1991, Specification for the Reinstatement ofopenings in Highways, encourages the use of AlternativeReinstatement Materials (ARM) to promote the use of recycledmaterial under the EU Waste Directive.

Supporting this Directive, EDF Energy Networks and LaingO’Rourke Infrastructure sought a process that would re-use asmuch of the circa 100,000 tonnes of material that is producedduring excavation works, and had previously been sent tolandfill every year.

Their requirement was for a viable, recycled product that couldbe used as the replacement of Type 1 sub-base as defined bythe Specification for Highways Works.

O’Keefe Utilities had identified a need for a suitable ARM forthe utilities industry and through extensive research;laboratory testing and field trials are able to produce amaterial that achieves the performance of a Structural Materialfor Reinstatement (SMR).

PV1 is a SMR as defined under the New Roads and Street WorksAct 1991 in the Second Edition of the Street Works Code ofPractice: Specification for the Reinstatement of Openings inHighway.

This document will provide an overview of the process,including the production and control methods of PV1 whichhas been designed specifically for the use as a replacement ofvirgin, quarried Type 1 for use as backfill and sub-base layer(s)for reinstatement in the highways.

Introduction

driver issued a delivery ticket with individual

reference number

inspection, does the material comply with

defined acceptance Criteria?

Visual inspection

PV1 loaded onto individuallorries which are weighed and a ticket issued to each driver

Conformity Testing as perHAUC,

SHW 800 seriesand WRAP using

BSEN Test Methods

Data management system Coronawhen back fill is complete

Non-compliantmaterialsrejected

Material sample istaken, data base

updated & material removed to a land fill site

Non-compliantmaterial is

rejected

Compliant material tipped in

Arisings delivered toSMARTR Processing Facility

Stabilised material reintroduced to SMARTR plant and mixed with a secondary binder to

produce PV1 to order

Graded material loaded into SMARTR plant & mixed with a

primary binder producinga stabilised material

Arisings screened,graded & stored

SMARTR Quality Protocol

The O’Keefe SMARTR ™ Processing Plant

O’Keefe Utilities have designed, developed andcommissioned the plant and process to receive utilityarisings from the London Boroughs to recycle into aBritish Standard compliant product for use as sub-baseand backfill for reinstatement.

The process involves segregating, screening, re-grading,weighing, treating and stabilising the material ready fordispatching.

We refer to this process as the O’Keefe SMARTR™process which is an acronym for:Stabilising Materials from Arisings - Re-grading &Treating for Re-use.

The O’Keefe SMARTR™ Process

1. A visual and olfactory inspection will be made of theexcavated material on arrival to the processing facilities.Each load will be weighed and a ticket issued to the grab driver.

2. Material is stockpiled in designated storage areas wherea secondary inspection is carried out of the entire load.

3. Non-compliant material will be stored in a separatestorage area until removed to an external landfill site.The database will record load rejected, reason and theorigin of material. LOR will be advised and contaminationtests carried out.

4. Accepted material is screened and any oversized particlesare crushed to <40mm and stockpiled.

5. Graded material is loaded into the SMARTR™ plantand mixed with a primary binder producing a stabilisedmaterial. This is then stored ready for batching thatwill be carried out on demand as required forreinstatement.

6. The stabilised material is loaded into the SMARTR™plant where a secondary binder is introduced and thematerial is treated producing the O’Keefe SMR PVI.

7. This is a fully automated system, which ensures thecorrect quantity of binder is added to the material usingcomputer controls and weighing belts.

8. The Pavimentum (PV1) is produced and used daily witha batch reference number issued to each grab lorry driveras they leave the Process Facility.

9. The batch reference number will be uploaded to Corona(the Laing O’Rourke Data Management System) againstthe relevant opening notice number, on completion ofbackfill.

10. The batch reference number will be entered into Mayrise(the EDF Energy ETON Street Works ManagementSystem), when the Section 70 registration notice isissued.

The S

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The SMARTR Process TM

WRAP have provided guidelines in their Quality Protocol of Aggregates from Inert Waste, revised edition: ISBN 1-84405-217-6,which have been applied to our process. All of the factory controls and quality management systems are compliant with Britishand European Standards.

In addition to our Factory Production Control manual and Method Statement of Production the SMARTR™ QualityProtocol incorporates the following:

How the Process Meets British and European Standards

1. Organisation: Management and staffresponsibilitiesResource ManagementAudit and Records

2. Control Procedures: Production managementInspection, calibration and control of equipmentHandling and storageProduction process control

3. Inspecting and Testing Composition of the mixtureof constituents and Sampling from stockpilesmixture duringproduction:

4. Non-conformity: Constituent non conformityProduct non conformity

5. Recovery from Incoming waste materialsinert waste: Receipt of waste materials

Records of received materialAccepted loadsRejected loadsWeighing and categorisingRe-inspecting and stockpiling

6. Quality Control: Testing procedure and frequencyStockpiling/dispatchPlacement training/inspection

7. Information Test resultsby producer: Test procedures

Details of factory production control manual

8. Quality Statement: Conforming to the protocol provided by WRAP

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Pavimentum (PV1)

PVI will be used on the day of production, batch volumes willbe determined by planned reinstatement requirements.Production will commence at approximately 6.30am and PV1is loaded directly onto the grab wagons for deployment tosite for placement. The material will be used within 8 hoursof production.

PVI will be covered with sheeting during transit and whilststoring on site prior to placement, as per best practice methods.

Recording batch details – Web portal Corona

All grab drivers will be issued with a batch reference numberonce PV1 has been loaded and they are exiting theProcessing Facility. This number will be recorded against thespecific opening notice number on Corona (Laing O’RourkeData Management System) from site, on completion of thebackfill process.

Photographs of each stage of the compaction process will becaptured on Corona and are available live for LocalAuthorities to view on line. A clegg hammer test is alsocarried out as per best practice.

Batch reference details will be uploaded onto Mayrise (theEDF Energy Management System for Street Works) againsteach opening notice number when submitting the Section 70registration notice.

Compacting Pavimentum (PV1)

PV1 is an Alternative Reinstatement Material (ARM) and willbe laid as per the reinstatement methods in accordance ofAppendix A8, of the HAUC Specification for theReinstatement of Openings in Highways, New Roads andStreet Works Act 1991.

Quality Control for Dispatch and Batch Records of PV1

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The material is to be produced in accordance with the BS EN14227-1 Hydraulically Bound Mixtures Specification Part 1:Cement Bound Granular Mixtures. PVI is classified a CBGM A

In addition, the material meets the specifications forproduction, storage and testing in accordance with Series 800of the Manual of Contract Documents for Highway Works

Volume 1 Specification for Highway Works Amendment May2009, and the quality guidelines set out by the Waste andResources Action Plan (WRAP).

The testing schedule of PVI as required by HAUC, SHW: 800series and WRAP is listed below:

Product Criteria

Test Description Test Method Source ofrequirement

Frequency

WAC Contaminationanalysis

Full waste suite of solids and 2-part leachate suite MCERTS Lab

BS EN 13286-41

WRAP1 per 2 weeks on rejected and accepted material

Sulphate/organic analysis Clause 710 SHW: 820.11 per 2 weeks on acceptedmaterial

Particle sizedistribution (grading) BS EN 933-1 SHW: 821.2 2 per week

Moisture content BS EN 1097-5 SHW: 821.3 2 per week in lab 1 per day at plant

Optimum water content by compaction test

BS EN 13286-4 SHW: 821.3 1 per week

Compressive strength SHW: 821.4 2 per week

Immediate bearingindex (tested 60-90 minutes after compaction)

BS EN 13286-47 O'KeefeQuality Control Process

2 per week

Strength afterimmersion

SHW:880 SHW: 821.2 1 per week

Fines quality(tested before addition of cement binder)

BS1377-2 SHW: 821.1 1 per month

Workability period BS EN 13286-45 O'KeefeQuality Control Process 1 per month

Frost susceptibilitytest

BS1924-2 HAUC A9.2 1 per month

Figure 1 Indicates the Particle Size Distribution GradingEnvelope for CBGM A. Four separate samples of PVI takenover a one-month period show consistent gradingcharacteristics within this envelope.

Performance Properties

Figure 1 Particle Size Distribution for PVI within the GradingEnvelope for CBGM A

Moisture Condition

Curing Condition

Bulk Density (Mg/m3)

Compressive Strength (N/mm2)

Mean Compressive Strength (N/mm2)

Volume Stability

At vibrating hammer optimum moisture content

14 days soaked & 14 days sealed

2.259

2.221

2.208

2.230

2.223

2.234

2.114

2.158

2.184

2.168

2.193

2.184

5.2

92%

28 days sealed

5.7

4.9

5.1

6.2

5.5

5.2

2.8

1.6

2.4

2.8

2.9

2.8

5.6

2.3

2.8

At 2.5kg rammer optimum moisture content

14 days soaked & 14 days sealed

28 days sealed

84%

At vibrating hammer optimum moisture content

14 days soaked & 14 days sealed

2.200

2.197

2.202

2.198

2.215

2.221

2.211

2.195

2.156

2.175

2.144

2.149

4.2

86%

28 days soaked

4.5

3.9

5.0

4.7

3.0

2.9

3.0

2.9

3.6

3.6

3.8

4.2

4.8

3.0

3.6

At 2.5kg rammer optimum moisture content

14 days soaked & 14 days sealed

28 days soaked

100%

3.0

14 days soaked & 14 days sealedAt vibrating

hammer optimum moisture content* 28 days

soaked 4.0

90%

* with additional 4 hours between mixing of cement and compaction

Particle size distribution100

90

80

70

60

50

40

30

20

10

0

Nominal aperture of test sieve (mm)0.01 0.1 1 10

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100

Figure 2 Assessments of Performance Properties of PVI

The results show that the compressive strength of the material meets the HAUC requirement and the measured volume stabilityexceeds the 80% value required by the Specification for Highway Works Series 800.

WRAP Materials Resource Efficiency in Street Works HAUC/RAUC released the following Memorandum of Understanding Updateon the 10th March 2009:

HAUC & Local Authorities Memorandum of Understanding

“The Commitment

This memorandum of understanding sets out the Local Authority and Regional & National HAUC/RAUC commitment to:

• approving and encouraging the use of recycled and stabilised materials in street works where they meet specifiedperformance and quality requirements;

• supporting the Street Works community (Utility Companies, Contractors, Local Authorities and Material Suppliers) inincreasing the use of recycled and stabilised materials and reducing the waste arisings sent to landfill;

• using trial data and case study information to inform the approval of recycled and stabilised materials in street works; and

• pro-actively sharing knowledge on the use of recycled and stabilised materials.”

EDF Energy Networks, Laing O’Rourke Infrastructure and O’Keefe Utilitiesare committed to providing a quality, recycled product for use inreinstatement in the highways.

O’Keefe Utilities LimitedSt. Andrew's House

1 Dreadnought Street, off Boord Street, Greenwich, London SE10 0PUTel: 020 8858 9124 Fax: 020 8858 0806

info@okeefe.co.uk