Investigation for Asbestos in Soils - Brent Council · 2018-03-16 · Investigation for Asbestos in Soils Paddington Old Cemetery – School Plot ... multidisciplinary environmental

Investigation for Asbestos in Soils Paddington Old Cemetery – School Plot Delta-Simons Project Number 17-1179.02

Environment | Health & Safety | Sustainability

Investigation for Asbestos in Soils Paddington Old Cemetery – School Plot Presented to Brent Council Issued: February 2018 Delta-Simons Project No. 17-1179.02



Report Details

Client Brent Council

Report Title Investigation for Asbestos in Soils, Paddington Old Cemetery - School Plot

Site Address Paddington Old Cemetery, Willesden Lane, Kilburn, London. NW6 7SD

Project No. 17-1179.02

Report Date February 2018

Delta-Simons Contact Simon Clennell-Jones ([email protected])

Quality Assurance

Issue No. Status Issue

Date Comments Author Technical Review Authorised

1 ISSUE 23RD

February 2018

-

Simon Clennell-Jones

Divisional Director

Simon Brown Director

Simon Clennell-Jones

Divisional Director

About us Delta-Simons is a trusted, multidisciplinary environmental consultancy, focused on delivering the best possible project outcomes for customers.

Specialising in Environment, Health & Safety and Sustainability, Delta-Simons provide support and advice within the property development, asset management, corporate and industrial markets. Operating from nine locations - Lincoln, Birmingham, Dublin, Durham, Leeds, London Manchester, Norwich and Nottingham, - we employ over 70 environmental professionals, bringing experience from across the private consultancy and public sector markets.

Delta-Simons is proud to be a founder member of the Inogen® Environmental Alliance, enabling us to efficiently deliver customer projects worldwide by calling upon over 4,330 resources in our global network of consultants, each committed to providing superior EH&S and sustainability consulting expertise to our customers. Inogen Environmental Alliance offers its clients more consultants, with more services in more countries than the traditional multinational consultancy.

mailto:[email protected]



Table of Contents

Figures

Figure 1 Site Location Plan

Figure 2 Exploratory Hole Location Plan

Appendices

Appendix A Limitations

Appendix B Photographic Record

Appendix C Exploratory Hole Logs

Appendix D Soil Chemical Analysis Results

1.0 INTRODUCTION .............................................................................................................................................................. 1 1.1 Appointment ........................................................................................................................................... 1 1.2 Context & Purpose ................................................................................................................................. 1 1.3 Scope of Works ...................................................................................................................................... 1 1.4 Limitations .............................................................................................................................................. 1

2.0 SITE DETAILS................................................................................................................................................................... 2 2.1 Site Setting ............................................................................................................................................. 2

3.0 SITE INVESTIGATION .................................................................................................................................................... 4 3.1 Intrusive Investigation ............................................................................................................................ 4

3.1.1 Health & Safety Considerations .................................................................................................... 4 3.2 Scope of Ground Investigation and Rationale ....................................................................................... 4

3.2.1 Scope ............................................................................................................................................ 4 3.2.2 Rationale ....................................................................................................................................... 4

3.3 Ground Investigation Factual Data ........................................................................................................ 4 3.4 Environmental Sampling, In-Situ Testing and Laboratory Analysis ....................................................... 5

4.0 GROUND SUMMARY ...................................................................................................................................................... 6 4.1 Introduction ............................................................................................................................................ 6 4.2 Ground Model ........................................................................................................................................ 6 4.3 Visual or Olfactory Evidence of Contamination ..................................................................................... 6

5.0 CONTAMINATION FINDINGS ........................................................................................................................................ 7 5.1 Asbestos Findings .................................................................................................................................. 7 5.2 Discussion .............................................................................................................................................. 7

6.0 CONCLUSIONS & RECOMMENDATIONS ................................................................................................................. 8

Investigation for Asbestos in Soils Paddington Old Cemetery – School Plot Delta-Simons Project Number 17-1179.02 Page 1


1.0 Introduction 1.1 Appointment

Delta-Simons Environmental Consultants Limited (“Delta-Simons”) was instructed by the Environmental Services department of Brent Council (the “Client”) to undertake an Investigation for Asbestos in Soils at the School Plot, Paddington Old Cemetery, London NW6 7SD (the “Site”).

1.2 Context & Purpose

The ‘School Plot’ comprises a rectangular fenced area of land in the far south-west corner of Paddington Old Cemetery. It has been utilised for a period by Salusbury Primary School as a garden for outdoor teaching including the growing of vegetables, raising of chickens and other outdoor activities. The area is separated from the wider cemetery by a fence, with a gate present at the north west corner which is locked during school times. This ‘School Plot’ is also referred to ‘the Site’ throughout this report.

Following the identification of asbestos within previously imported soils at an area of the Paddington Old Cemetery known and ‘the mound’ and located to the north-east of the ‘School Plot’, concerns were raised about the potential for asbestos to be present in the ‘School Plot’.

The aim this report is to detail the findings of an investigation for the presence of asbestos within shallow soils (topsoil) within the School Plot.

1.3 Scope of Works

The scope of the investigation and layout of this report has been designed with consideration of CLR11 (Environment Agency, 2004a) and BS 10175: 2013 Investigation of Potentially Contaminated Sites – Code of Practice (BSI, 2011) and guidance on land contamination reports issued by the Environment Agency (EA) (2010a).

The project was carried out to an agreed brief as set out in Delta-Simons’ proposal dated 4th February 2017 (ref.1 17-1179.02/SCJ/L04). The scope of works is outlined in Section 3.2.

This investigation was undertaken principally to gain data on the presence and concentration of asbestos in soils within the ‘School Plot’.

1.4 Limitations

The assessment is limited to the issues agreed within the proposal for the works. Notes on limitations associated with this assessment are provided in Appendix A. In addition, there are the following specific limitations that apply to this assessment:

▲ The investigation works were limited to shallow and surface soils (topsoil) within the Site.

▲ The report does not include a formal or detailed risk assessment of the concentrations encountered and has been prepared on a rapid timescale to ensure the parents and teachers at Salusbury Primary School are kept appraised.

▲ The report was limited to sampling for asbestos in soils alone, it has not included and assessment for any other contaminants and it does not assess the overall suitability of the soils for use for a school garden.



2.0 Site Details 2.1 Site Setting

A summary of the current Site status, environmental setting and key historical features is presented below. This has been summarised from readily available online data which should be consulted for further detail.

Co-ordinates Centred approximately at National Grid Reference 832142, 459382

Elevation 33 m AOD

Area Approximately 0.082 Ha

Site Location The School Plot is located in the far south-western corner of an active cemetery within a wider mixed residential and commercial setting. A Site location map is provided as Figure 1.

Current Site Use The Site currently comprises a garden including pathways, some well-established trees and shrubs, sheds and storage, a henhouse, raised beds, planters and a pond. The Site is accessed from the south-west via a gate connecting to Salusbury Primary School with a secondary access, locked during school hours, exiting into Paddington Old Cemetery.

The southern and western boundaries of the ‘School Plot’ are formed by the existing cemetery walls.

The ‘School Plot’ is variable surfaced reflecting its use as a garden with extensive areas of grassed and bare soils present. Local areas of the ‘School Plot’ may be described as ‘hummocky’ notably associated with the pond and other landscaping features.

A photographic record of the ‘School Plot’ is presented in Appendix B.

It is understood that the ‘School Plot’ was provided to Salusbury Primary School for use as a garden by Brent Council some time ago (specific date not known), it historically formed part of the Paddington Old Cemetery.

Surrounding Land Uses

The areas to the north and east comprise the Paddington Old Cemetery and are separated from the ‘School Plot’ by a fence. Salusbury Primary School is located to the west; it is understood the school has been present since around 1902.

To the south of the ‘School Plot’, beyond the cemetery wall is a circa two storey brick-built terrace including a medical centre and a number of other units.

To the north / north-east of the ‘School Plot’, across a hardstanding path is ‘the mound’, an area of the cemetery which was raised through importation of Made Ground thought to extend approximately 2.00 – 2.50 m below ground level (bgl).

The mound is at higher elevation than the ‘School Plot’.

Environmental Setting

Published BGS maps indicate that the Site is directly underlain by the London Clay Formation, with no superficial deposits recorded on Site. The London Clay formation is classified as Unproductive Strata (not a water bearing strata).

Readily accessible online mapping indicates that the Site is not in a Source Protection Zone (SPZ), the nearest surface water course is Grand Union (Paddington) Canal at approximately 1.0 km south of the Site.

Previous Known Contamination Issues

The School Plot has historically formed part of the cemetery. There are no previously known contamination issues at the ‘School Plot’; no testing or other information has been made available to Delta-Simons in relation to the ‘School Plot’.



A representative from Salusbury Primary School indicated that small volumes of soils may have been brought into the School Plot as part of works to construct the pond and also as part of the general development and operation of the garden. It is understood that parents and others have brought in plants and containers as well as other items in the past.

Within the wider cemetery, the ‘mound’ located to the north-east was formed by the importation of materials from various locations (unknown) within the last few years. The aim of the importation was to provide a raised area for further burials.

Burials have been undertaken into the mound, during the burial process, asbestos was identified. The presence of asbestos within these imported materials was considered to be of significant concern to the Client (and others) and several investigations and risk assessments were undertaken for the mound:

1. Eton Environmental Group Ltd. Report for Excavation Investigation for Asbestos Containing Materials V2 dated, 24th November 2017

2. Soil and Water Solutions Ltd. Grave no. 122 Re-Opening Verification Report dated, 14th November 2017

3. Delta-Simons (2017), Initial Options Review – Asbestos Contamination in Soils, Paddington Old Cemetery, 8th December 2017 Project No. 17-1179.01.

4. Delta-Simons (2018). Asbestos Investigation – Factual Report, Paddington Old Cemetery, January 2018 Project No. 17-1179.01;

5. Delta-Simons (2018). Detailed Quantitative Risk Assessment – Asbestos, Paddington Old Cemetery, January 2018 Project No. 17-1179.01.

Of 80 soil samples obtained during the ground investigations on the mound, 20 have been found to contain asbestos, with the highest concentrations recorded as being <0.001% (at or below the limit of detection for the test1).

Following completion of these reports a public meeting was held in January 2018.

Whilst the risk assessments did not demonstrate a potential increased risk to the health of recreational adult users of the mound, a potential increased risk was identified for those involved in grave excavations.

In conjunction with the findings of the investigations, concerns were raised as to whether asbestos containing materials could be present within the ‘School Plot’ and on that basis the investigation reported herein was commissioned as a precaution.

No firm / documentary evidence has been presented to Delta-Simons prior to this report confirming that any soils had been imported into the ‘School Plot’ by Brent Council or their Contractors.

1 A ‘detection limit’ is the lowest level/limit that a laboratory is permitted to report within it accreditation for a specific test method.



3.0 Site Investigation 3.1 Intrusive Investigation

Delta-Simons carried out intrusive investigation work on the 9th February 2018 to obtain environmental samples for subsequent laboratory analysis to assess the presence and concentration of asbestos within shallow soils on the ‘School Plot’.

The investigation was limited to investigating the shallow soils (top 15cm) on the following basis:

▲ The contaminant of concern is asbestos and is considered most likely to be found in the surface soils if present at all;

▲ The nature of asbestos is that it represents a risk from inhalation of released fibres and such a release, in normal gardening use, is only likely to happen from the shallowest of soils exposed to air, and, only for a limited period of the year would such soils become sufficiently dry for a fibre release event to occur.

3.1.1 Health & Safety Considerations

Given the shallow depth of the works (top 15cm) and the technique chosen (hand digging), no utilities clearance/scanning was required.

As with much of this area of London, an initial assessment of the Site identified a Low to Moderate risk in relation to Unexploded Ordnance (UXO), however, as the investigation was by hand digging only to shallow depths no specific precautionary measures were required for the works.

3.2 Scope of Ground Investigation and Rationale

3.2.1 Scope

The ground investigation comprised the following items:

▲ Excavation and supervision of all works by a Delta-Simons Geo-Environmental specialist (Simon Clennell-Jones).

▲ All intrusive locations were logged in general accordance to BS5930:2015 Code of Practice for Site Investigations;

▲ Excavation of twenty shallow Hand-dug trial pits (HDTP01 to HDTP20) to a maximum depth of 0.15m bgl;

▲ Sampling of associated topsoil at each location;

▲ Reporting of findings.

3.2.2 Rationale

The following table details the rationale for the locations.

Location Rationale

HDTP1 to HDTP20

Exploratory positions were located to sample a range of visibly different soils across the Site and to provide a reasonable coverage of the Site. Soils which appeared to have a greater degree of anthropogenic inclusions such as those within raised beds were targeted.

The sampling approach may be described as a combination of targeted and no systematic random sampling.

3.3 Ground Investigation Factual Data

The investigation locations and the general layout of the ‘School Plot’ were surveyed in by the appointed surveying contractor (Avion Maa) to an accuracy of approximately +/- 0.1m. An intrusive exploratory hole location plan is presented as Figure 2.



Delta-Simons engineer verified borehole logs are presented as Appendix C. 3.4 Environmental Sampling, In-Situ Testing and Laboratory Analysis

Sampling was undertaken using a brand new metallic trowel purchased for the works and this was cleaned between locations using industrial wipes to minimise cross contamination.

At each location a fresh set of nitrile gloves were utilised to minimise the risk of any cross contamination.

Samples were placed within a laboratory provided tub and labelled with the project details. Samples were collected and transported under chain of custody to I2, a UKAS accredited laboratory having been dispatched on 12th February 2018 following secure storage over the weekend with containers stored in a sealed double bag. Due to the contaminant of interest being limited to asbestos, no preservatives were required.

Samples were stored in accordance with Delta-Simons’ quality procedures to maintain sample integrity and preservation and to minimise the chance of cross contamination. Records of the samples taken as part of the site investigation works, including their depths and location, are included within the exploratory hole records in Appendix C.

The rationale for chemical analysis is presented in the table below and the results of the chemical laboratory testing are included in Appendix D.

Analytes No. of Samples

Tested Rationale

Asbestos presence in soils plus quantification where positively detected. 20 samples Contaminant of interest



4.0 Ground Summary 4.1 Introduction

The sections below summarise the ground conditions encountered during the site investigation.

4.2 Ground Model

Exploratory hole logs are presented in Appendix C. A summary of the observed ground conditions at the Site is provided below.

Summary of Observed Ground Conditions

Strata Typical Strata Description

Depth Range of Strata Base (m)

Typical Thickness (m) Comments

Topsoil

Soft to firm grey/brown slightly gravelly CLAY.

Gravel is angular to rounded typically fine

occasional flint and brick.

0.15 0.15

The topsoils sampled were variable across the different sampling locations indicative of a range of source/parent

materials and evidence of amelioration with compost was noted in some

locations.

4.3 Visual or Olfactory Evidence of Contamination

Prior to the works an inspection of the ‘School Plot’ was made to identify any evidence of contamination in the form of any visible asbestos containing materials on the site surface.

No visible evidence of asbestos containing materials were identified during this inspection.

No visible asbestos containing materials were identified in the samples obtained during sampling.



5.0 Contamination Findings 5.1 Asbestos Findings

The results of the sample analysis are presented in Appendix D.

Asbestos was identified as being present in three of the twenty samples tested. It is noted that none of the samples were visually observed to contain visible asbestos during sampling.

The following table summarises those samples where asbestos was identified.

Location Sample Depth (m)

Asbestos Containing Material Types Detected (ACM)

PLM Results

Asbestos by hand picking/weighing

(%)

Total % Asbestos in Sample

HDTP04 0.00-0.15 Loose Fibres Chrysotile < 0.001 < 0.001

HDTP11 0.00-0.15 Loose Fibrous Debris Amosite < 0.001 < 0.001

HDTP15 0.00-0.15 Loose Fibrous Debris Chrysotile < 0.001 < 0.001

HDTP04 is an area which may have once been a raised bed located at the far south-east of the Site.

HDTP11 is a raised bed located west of the centre of the Site associated with the Year 5 Allotment.

HDTP15 is an area in the far west of the Site located between a path and the boundary wall with the School.

Where tested, similar topsoils to those found at each of the above sampling points were not found to contain asbestos in the testing undertaken.

5.2 Discussion

No criteria exist to assess the risks from asbestos in soils on a generic basis, the sampling has identified asbestos fibres to be present.

Two of the three types of common asbestos fibres, namely chrysotile and amosite, were identified.

The concentrations of asbestos recorded were below the detection limit of the laboratory and so can be considered only just detectable.

The distribution of positive samples does not indicate any obvious pattern. The detections of asbestos does not appear to be associated with a specific type of topsoil material.



6.0 Conclusions & Recommendations The investigation has been undertaken in order to provide information on the presence and concentrations of asbestos within the soils on the ‘School Plot’.

The investigation has detected asbestos present in a limited number of topsoil samples (3 of 20) comprising loose chrysotile and amosite fibres. Quantification analysis of the soils indicated <0.001% total asbestos in the samples. None of the samples had visual evidence of asbestos containing materials and no visual evidence was identified during a surface inspection of the ‘School Plot’.

No specific pattern appears apparent as to the distribution of impacts. It is observed that the samples recording asbestos as present are not located in the areas nearest the ‘mound’, rather they further from the mound.

It is not possible to confirm how the asbestos present in these samples came to be present within the soils, where it originated from or whether it is in any way related to the asbestos found in the mound. It was observed on Site that a range of different topsoil materials are present, and some evidence exists that materials have been brought to the ‘School Plot’ from elsewhere to help develop and landscape the garden from elsewhere and the materials which have been found to be impacted in the raised beds appear to be different to the topsoils located in the mound area (off-site).

The concentrations recorded are considered to be very low and potentially indicative of urban background asbestos in soil concentrations based on the authors experience of investigations in urban areas. A review of the literature has identified an absence of robust data on the concentrations of asbestos (natural or from man-made inputs) in UK soils2.

Careful consideration needs to be given to the findings as the presence of asbestos has been confirmed from the work undertaken.

It would be possible, with further input from those involved in using the ‘School Plot’ to estimate the potential increased risk that may have be associated with historical use/interaction with the soils through a Detailed Quantitative Risk Assessment.

However, in advance of any such risk assessment, those who have interacted with the soils should take reassurance from the following:

▲ Asbestos only represents a risk when fibres are inhaled, fibres are only released from soils once soils are sufficiently dry. Outdoors in the UK dry enough conditions for fibre release are considered likely to be present for only a very short part of the year, typically over the hottest and driest days of the summer;

▲ The concentrations encountered are very low, below the limit of detection of the standard tests;

▲ The concentrations encountered are potentially typical of urban background concentrations associated with the legacy of industrial development in urban centres in the UK. It is likely that there are urban soils in private and public land across London which are likely to have similar and potentially higher concentrations of asbestos.

At the time of writing, the ‘School Plot’ is not being actively used by pupils. Due to the finding of the very low concentrations of asbestos it is recommended that use by pupils does not recommence until discussions with the School management and other stakeholders have been undertaken and any further assessment or other actions undertaken.

It should however be highlighted that concentrations detected are very low and ongoing management of the ‘School Plot’ (e.g. feeding the chickens, use by staff for walking etc.) is considered highly unlikely to result in any significant fibre release and could continue in the short term in parallel to discussions on the appropriate next steps.

It must be emphasized that the concentrations of asbestos found and, therefore, the associated exposure will be very low. Asbestos is one of many chronic contaminants found in urban air and long-term exposure to very

2 JOHNSON, CC, ANDER, EL, CAVE, MR and PALUMBO-ROE, B. 2012. Normal background concentrations (NBCs) of contaminants in English soils: Final project report. British Geological Survey Commissioned Report, CR/12/035.



low levels of asbestos can and does occur in urban environments without any short or long-term impact to health for many people.

It is recommended that the contents of this report be discussed with the School management and other stakeholders to determine appropriate next steps.

The decision to take any further action should including undertaking remediation (if any) should be an informed one based on the specific circumstances at the Site and through engagement with stakeholders. The simple presence of asbestos at the concentrations encountered does not necessarily mean that remediation is needed, however, it may be considered on a pragmatic and precautionary basis.

Given the concentrations encountered at the ‘School Plot’ are likely to be typical of urban background the Client (Brent Council) needs to carefully consider whether action is merited in this case and other cases where the contamination is present at such low concentrations. This should be considered in the context of previous decisions where Local Authorities have, under their statutory powers (Part 2A of the Environmental Protection Act 1990) determined that other sites including those with much higher concentrations of asbestos do not meet the threshold for definition as Contaminated Land and would not attract funding for remediation.


Figure 1 – Site Location Plan

Site Location

Site Location Map

School Plot

Paddington

To Scale@A4

1

15 February 2018

17-1179.02

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AW

SC-J

Scale: 1 / 500,000 @ A4

LEGEND

Site Boundary

Scale: 1 / 10,000 @ A4

TITLE: PROJECT NO:

FIGURE NO:

SCALE:

REVISION:

DRAWN BY:

CHECKED BY:

DATE:

Contains OS data © , Crown Copyright and Database Right (2016/2017)


Figure 2 - Exploratory Hole Location Plan

Not to Scale

1

15 February 2018

17-1179.02

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SC-J

Exploratory Hole Location Plan

School Plot

Paddington

TITLE: PROJECT NO:

FIGURE NO:

SCALE:

REVISION:

DRAWN BY:

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DATE:

LEGEND

Site Boundary

Hand Dug Trial Pit

HDTPx

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Gate

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Pond

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Shed

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Appendix A - Limitations


Limitations

The recommendations contained in this Report represent Delta-Simons professional opinions, based upon the information listed in the Report, exercising the duty of care required of an experienced Environmental Consultant. Delta-Simons does not warrant or guarantee that the Site is free of hazardous or potentially hazardous materials or conditions.

Delta-Simons obtained, reviewed and evaluated information in preparing this Report from the Client and others. Delta-Simons conclusions, opinions and recommendations has been determined using this information. Delta-Simons does not warrant the accuracy of the information provided to it and will not be responsible for any opinions which Delta-Simons has expressed, or conclusions which it has reached in reliance upon information which is subsequently proven to be inaccurate.

This Report was prepared by Delta-Simons for the sole and exclusive use of the Client and for the specific purpose for which Delta-Simons was instructed. Nothing contained in this Report shall be construed to give any rights or benefits to anyone other than the Client and Delta-Simons, and all duties and responsibilities undertaken are for the sole and exclusive benefit of the Client and not for the benefit of any other party. In particular, Delta-Simons does not intend, without its written consent, for this Report to be disseminated to anyone other than the Client or to be used or relied upon by anyone other than the Client. Use of the Report by any other person is unauthorised and such use is at the sole risk of the user. Anyone using or relying upon this Report, other than the Client, agrees by virtue of its use to indemnify and hold harmless Delta-Simons from and against all claims, losses and damages (of whatsoever nature and howsoever or whensoever arising), arising out of or resulting from the performance of the work by the Consultant.


Appendix B – Photographic Log


Site Photographs

Photograph 1 – View looking North from the south-east. HDTP4 was taken from the possible former raised bed in the left of the picture


Photograph 2 – View looking north-east, in the back of the picture, the Raised Bed from which HDTP11 was obtained can be seen.


Photograph 3 – Looking north-west, sample HDTP 15 was taken from the verge near the upturned sinks


Photograph 4 – Looking eastwards across grassed areas and bare ground


Photograph 5 – Hummocky ground in the south of the site


Appendix C – Exploratory Hole Logs

Description of Strata

MADE GROUND: Soft grey CLAY (Topsoil)

Hand pit complete at 0.15 m bgl.

LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.22

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES

Head Office3 Henley Way, Doddington Road

Lincoln, LN6 3QRTel: +44 (0) 1522 882555

Email: [email protected]

Project No:

Project:

17-1179.02Hole ID:

HDTP01Page:1 of 1

Paddington Cemetery Greenspace

Hand Dug Trial Pit LogDate:

09/01/2018Client:

Brent Council

Dimensions and Orientation:Bearing:

Inclination:

Remarks:Hand dug shallow pit terminated as appropriate. No visible asbestos or other contamination identified.

Coordinates:E524606.94 N183565.80

Elevation (mAOD):33.37

Excavated By:DS

Plant Used: Logged:SCJ

Checked: Approved: Scale:1:30


MADE GROUND: Soft grey slightly gravelly CLAY. Gravel is angular to rounded flint and brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.32

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP02Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524611.76 N183559.44


Excavated By:DS




MADE GROUND: Soft brown/grey very gravelly CLAY. Gravel is angular fine brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.13

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP03Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524618.51 N183548.48


Excavated By:DS




MADE GROUND: Soft brown/grey very gravelly CLAY. Gravel is angular fine brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.03

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP04Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524619.39 N183545.20


Excavated By:DS




MADE GROUND: Soft brown/grey slightly gravelly CLAY. Gravel is angular fine brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.02

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP05Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524622.31 N183541.29


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.02

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP06Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524611.84 N183535.55


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.45

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP07Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524609.39 N183532.13


Excavated By:DS




MADE GROUND: Soft tan/grey CLAY (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.41

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP08Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524609.26 N183536.23


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.27

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP09Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524608.46 N183544.81


Excavated By:DS




MADE GROUND: Soft brown sandy CLAY. Highly organic (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.32

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP10Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524600.84 N183545.30


Excavated By:DS




MADE GROUND: Soft brown grey slightly gravelly CLAY. Gravel is fine to medium brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.57

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP11Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524590.07 N183543.45


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.58

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP12Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524587.91 N183539.56


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.60

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP13Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524587.62 N183536.36


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.51

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP14Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E52457981.00 N183542.68


Excavated By:DS




MADE GROUND: Firm brown grey CLAY (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.15

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP15Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524587.35 N183527.21


Excavated By:DS




MADE GROUND: Soft brown grey sandy CLAY (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.42

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP16Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524597.57 N183522.51


Excavated By:DS




MADE GROUND: Soft grey gravelly CLAY. Gravel is fine to medium angular brick and flint (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.36

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP17Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524601.31 N183524.80


Excavated By:DS




MADE GROUND: Soft grey gravelly CLAY. Gravel is fine angular brick (Topsoil)


LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.11

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP18Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524612.01 N183566.71


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.38

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP19Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524598.06 N183557.48


Excavated By:DS






LegendStrata Depth

(m)

0.15

Reduced Level

(mAOD)

33.45

WaterStrike

(m)

Sample Details

Depth (m) Type Ref

ES1

Test Details

Depth (m) Results

0.00 -0.15

ES


Lincoln, LN6 3QRTel: +44 (0) 1522 882555


Project No:

Project:

17-1179.02Hole ID:

HDTP20Page:1 of 1



09/01/2018Client:

Brent Council


Inclination:


Coordinates:E524591.59 N183556.56


Excavated By:DS




Appendix D – Soil Chemical Analysis Results

This certificate should not be reproduced, except in full, without the express permission of the laboratory. The results included within the report are representative of the samples submitted for analysis.

Iss No 18-75752-1 Paddington Old Cemetery - School Garden 17-1179.02

Page 1 of 7

Analytical Report Number: 18-75752

Project / Site name: Paddington Old Cemetery - School Garden

Lab Sample Number 906342 906343 906344 906345 906346

Sample Reference HDTP1 HDTP2 HDTP3 HDTP4 HDTP5

Sample Number None Supplied None Supplied None Supplied None Supplied None Supplied

Depth (m) 0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15

Date Sampled 09/01/2018 09/01/2018 09/01/2018 09/01/2018 09/01/2018

Time Taken None Supplied None Supplied None Supplied None Supplied None Supplied

Analytical Parameter

(Soil Analysis)

Un

its

Lim

it of

de

tectio

n

Accre

dita

tion

Sta

tus

Asbestos in Soil Screen / Identification Name Type N/A ISO 17025 - - - Chrysotile -

Asbestos in Soil Type N/A ISO 17025 Not-detected Not-detected Not-detected Detected Not-detected

Asbestos Quantification (Stage 2) % 0.001 ISO 17025 - - - < 0.001 -

Asbestos Quantification Total % 0.001 ISO 17025 - - - < 0.001 -



Page 2 of 7



Lab Sample Number

Sample Reference

Sample Number

Depth (m)

Date Sampled

Time Taken


(Soil Analysis)

Un

its

Lim

it of

de

tectio

n

Accre

dita

tion

Sta

tus

Asbestos in Soil Screen / Identification Name Type N/A ISO 17025

Asbestos in Soil Type N/A ISO 17025

Asbestos Quantification (Stage 2) % 0.001 ISO 17025

Asbestos Quantification Total % 0.001 ISO 17025

906347 906348 906349 906350 906351

HDTP6 HDTP7 HDTP8 HDTP9 HDTP10

None Supplied None Supplied None Supplied None Supplied None Supplied

0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15

09/01/2018 09/01/2018 09/01/2018 09/01/2018 09/01/2018


- - - - -

Not-detected Not-detected Not-detected Not-detected Not-detected

- - - - -

- - - - -



Page 3 of 7



Lab Sample Number

Sample Reference

Sample Number

Depth (m)

Date Sampled

Time Taken


(Soil Analysis)

Un

its

Lim

it of

de

tectio

n

Accre

dita

tion

Sta

tus





906352 906353 906354 906355 906356



0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15

09/01/2018 09/01/2018 09/01/2018 09/01/2018 09/01/2018


Amosite - - - Chrysotile

Detected Not-detected Not-detected Not-detected Detected

< 0.001 - - - < 0.001

< 0.001 - - - < 0.001



Page 4 of 7



Lab Sample Number

Sample Reference

Sample Number

Depth (m)

Date Sampled

Time Taken


(Soil Analysis)

Un

its

Lim

it of

de

tectio

n

Accre

dita

tion

Sta

tus





906357 906358 906359 906360 906361



0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15 0.00-0.15

09/01/2018 09/01/2018 09/01/2018 09/01/2018 09/01/2018


- - - - -

Not-detected Not-detected Not-detected Not-detected Not-detected

- - - - -

- - - - -



Page 5 of 7

18-75752

Paddington Old Cemetery - School Garden

Methods:

Qualitative Analysis

Sample

NumberSample ID

Sample

Depth

(m)

Sample

Weight

(g)

Asbestos Containing

Material Types Detected

(ACM)

PLM Results

Asbestos by hand

picking/weighing

(%)

Total %

Asbestos in

Sample

906345 HDTP4 0.00-0.15 103 Loose Fibres Chrysotile < 0.001 < 0.001

906352 HDTP11 0.00-0.15 125 Loose Fibrous Debris Amosite < 0.001 < 0.001

906356 HDTP15 0.00-0.15 119 Loose Fibrous Debris Chrysotile < 0.001 < 0.001

The analysis was carried out using our documented in-house method A006 based on HSE Contract Research Report No: 83/1996:

Development and Validation of an analytical method to determine the amount of asbestos in soils and loose aggregates (Davies et al, 1996)

and HSG 248. Our method includes initial examination of the entire representative sample, then fractionation and detailed analysis of each

fraction, with quantification by hand picking and weighing.

The limit of detection (reporting limit) of this method is 0.001 %.

The method has been validated using samples of at least 100 g, results for samples smaller than this should be interpreted with caution.

Both Qualitative and Quantitative Analyses are UKAS accredited.

Opinions and interpretations expressed herein are outside the scope of UKAS accreditation.

Analytical Report Number:

Project / Site name:

Your Order No:

Certificate of Analysis - Asbestos Quantification

The samples were analysed qualitatively for asbestos by polarising light and dispersion staining as described by the Health and Safety

Executive in HSG 248.

Quantitative Analysis



Page 6 of 7

Analytical Report Number : 18-75752


Water matrix abbreviations: Surface Water (SW) Potable Water (PW) Ground Water (GW) Process Water (PrW)

Analytical Test Name Analytical Method Description Analytical Method ReferenceMethod

number

Wet / Dry

Analysis

Accreditation

Status

Asbestos identification in soil Asbestos Identification with the use of polarised

light microscopy in conjunction with disperion

staining techniques.

In house method based on HSG 248 A001-PL D ISO 17025

Asbestos Quantification - Gravimetric Asbestos quantification by gravimetric method - in

house method based on references.

HSE Report No: 83/1996, HSG 248, HSG

264 & SCA Blue Book (draft).

A006-PL D ISO 17025

D.O. for Gravimetric Quant if

Screen/ID positive

Dependent option for Gravimetric Quant if

Screen/ID positive scheduled.

In house asbestos methods A001 & A006. A006-PL D NONE

For method numbers ending in 'UK' analysis have been carried out in our laboratory in the United Kingdom.

For method numbers ending in 'PL' analysis have been carried out in our laboratory in Poland.

Soil analytical results are expressed on a dry weight basis. Where analysis is carried out on as-received the results obtained are multiplied by a moisture

correction factor that is determined gravimetrically using the moisture content which is carried out at a maximum of 30oC.



Page 7 of 7

Asbestos Identification and Quantification

i2 Analytical Ltd 7 Woodshots Meadow, Croxley Green Business Park, Watford, Herts, WD18 8YS Telephone 01923 225404 | Company Registration No. 4750390 | VAT No. 821097249


Below is a flowchart of the pathway of asbestos testing with details of the three analysis stages performed by i2 Analytical, in accordance with HSG 248 and HSG 264 documents: Equipment and Sample preparation All equipment involved in the analysis is screened prior to use to ensure no source of contamination is introduced to the sample. Any equipment used is cleaned appropriately or safely disposed of as asbestos waste. The fume cabinet is cleaned between samples and routinely checked for safe extraction and contamination. All samples are oven dried overnight at < 100 °C in a covered clean tray and then maintained in sealed containers prior to analysis. Sufficient wet sample is used to ensure we have between 100 and 350 g of dried sample for screening. Stage 1 Analysis Asbestos Identification in SOIL and BULK samples – UKAS accredited The sealed sample is placed into a HEPA filtered fume cabinet, opened, and then crushed by hand using a mortar and pestle. A small portion of the sample is transferred to a petri dish where it is examined under a stereomicroscope for the presence of asbestos fibres. If no asbestos is discovered, the subsample is placed into a sealed plastic bag and a further portion transferred to a petri dish. This process is repeated until the entire sample has been screened. If no fibres have been identified, two “pinch” tests are performed. A pinch test involves immersing a needle into Refractive Index (RI) solution and then placing the needle into the finest fraction of the sample. Particles will adhere to the needle, and are transferred to a microscope slide prepared with RI solution. The slide is then

Stereomicroscope screening

Asbestos detected (confirmed by PLM) No asbestos detected (NAD)

Pinch test

Positive Negative

Free Fibres analysis

by PCOM

ACMs found Free Fibres found

Gravimetric analysis (concentration

according to HSG 264)

Gravimetric analysis (100% concentration)

Mass >0.0001g Mass <0.0001g

ANALYSIS COMPLETE


i2 Analytical Ltd 7 Woodshots Meadow, Croxley Green Business Park, Watford, Herts, WD18 8YS Telephone 01923 225404 | Company Registration No. 4750390 | VAT No. 821097249

examined under a Polarised Light Microscope (PLM) for the presence of asbestos fibres. If no asbestos fibres are identified, the sample can be reported as No Asbestos Detected (NAD). If fibres are identified in the screening process they are cleaned and transferred to a microscope slide prepared with the appropriate RI solution for asbestos type and their optical properties review under PLM. Each asbestos fibre type behaves in a characteristic way if viewed in this manner and a positive identification can be made. The Asbestos Identification method is purely qualitative with no numerical result or concentration of asbestos can be provided in accordance with the requirements of HSG 248:2005 and LAB 30 Edition 3 – January 2015. In a BULK material ONLY asbestos identification is carried out. The accepted percentage of asbestos content of known bulk material (concrete, plasterboard, etc.) is established in HSG 264 Appendix 2. Stage 2 Analysis Gravimetric Quantification in soil – UKAS accredited The entire representative sample is weighed and examined in a safety cabinet under a stereomicroscope and PLM as per the stage 1 analysis. Bulk asbestos containing material (ACM) is removed, placed in a sealable bag and weighed, and any free fibres washed with acetone or water before being dried and again placed in a sealable bag to be weighed. Care must be taken to avoid misidentification of non-asbestos fibres (organic or man-made mineral fibre) which will falsely increase the result. The mass of free fibres is combined with proportional mass of ACM (using factors from HSG 264 quantifying the proportion of asbestos present in each known ACM type) and reported as percentage of the whole sample mass. The method is performed on the whole subsample, with a minimum of 20 g of fine material reviewed by eye under a microscope for individual fibres or fibre fragments. The detection limit for the method is 0.001 %. Stage 3 Analysis Fibre Counting Quantification in soil – UKAS accredited This method is only usually performed where stage 2 cannot, but sample is confirmed positive – either identified by ‘Pinch’ test or via gravimetric test if the mass is below the measurable levels of an analytical balance. Up to 5 g of the residual fine material from the Gravimetric analysis is mixed with water using a 1:200 solid to liquid ratio. The sample is thoroughly mixed until the material is completely dispersed. After a brief settling period of several seconds, allowing larger non-asbestos particles to sink, an aliquot of water is taken and placed onto a 0.8 µm filter (either cellulose or cellulose nitrate) and attached to a vacuum pump to remove the water. The filter is placed onto a labelled microscope slide, cleared and dried carefully using a hot block. Slides are prepared using the Acetone-Triacetin mounting procedure before being transferred to a Phase Contrast Optical Microscope (PCOM) for evaluation. Fibres on the filter are counted using at least 500X magnification as per HSG 248. Each fibre (or fragment) found has to be individually measured (length and width), the volume assigned and mass calculated for each fibre type based on average density values. This is done separately for Type A (Chrysotile) and Type B (Amphiboles). The detection limit is variable depending on certain factors but is typically 0.001 %. V1 27.1

Documents

Investigation for Asbestos in Soils - Brent Council · 2018-03-16 · Investigation for Asbestos in Soils Paddington Old Cemetery – School Plot ... multidisciplinary environmental