CONTAMINATED LAND RISK ASSESSMENT - Vail …...Risk Assessment, Mineral Extraction Soil Planning The Nanotechnology Centre, Herschel Building, Kings Rd, Newcastle upon Tyne NE1 7RU

CONTAMINATED LAND RISK ASSESSMENT

PHASE 1 DESK TOP STUDY

BNP Paribas Real Estate

Land at Chawton Park Road

Alton

Soil Environment Services Ltd

October 2013


The Nanotechnology Centre, Herschel Building, Kings Road, Newcastle upon Tyne, NE1 7RU

Tel. 0191 243 0686

Fax. 0191 222 3528 Email: [email protected]

Our Ref: SES/BNP/CPR/1#1 Date: 22nd

October 2013

Client:

BNP Paribas Real Estate Advisory & Property Management UK Ltd

5 Aldermanbury Square

London

EC2V 7BP

CONTAMINATED LAND RISK ASSESSMENT

PHASE 1 DESK TOP STUDY


Alton

A report prepared on behalf of Soil Environment Services by:

Louise Tavasso BSc

Environmental Consultant

Checked by:

Dr Robin S Davies BSc PhD MISoilSci PGC Contaminated Land Management

Managing Director

INSTITUTE OF PROFESSIONAL SOIL SCIENTISTS

This report has been prepared by Soil Environment Services

with all reasonable skill, care and diligence, within the

terms of the Contract with the Client. The report is the

property of the client and Soil Environment Services accept

no responsibility of whatever nature to third parties to

whom this report may be made known. No part of this

document may be reproduced without prior written

approval of the Client.

Soil Environment Services Agricultural Land Classification, Contaminated Land

Risk Assessment, Mineral Extraction Soil Planning The Nanotechnology Centre, Herschel Building, Kings Rd, Newcastle upon Tyne NE1 7RU

Tel: 0191 243 0686 Fax: 0191 222 3528 Email: [email protected] www.soilenvironmentservices.co.uk

BNP Paribas Real Estate Contaminated Land Risk Assessment Chawton Park Road

Soil Environment Services Page 3

CONTENTS

Page

1. INTRODUCTION AND OBJECTIVES 4

2. SITE CHARACTERISATION AND FORMER INVESTIGATIONS 5

3. CONCEPTUAL SITE MODEL 9

3.1 Sources 9

3.2 Receptors 9

3.3 Pathways and plausible pollutant linkages 10

4. RISK ASSESSMENT 12

4.1 Human health 12

4.2 Controlled waters 13

4.3 Ecology 13

5. UNCERTAINTIES AND PHASE 2 PROPOSALS 14

DRAWING 1 Current site setting

APPENDIX A Historical maps

APPENDIX B Environmental data



1. INTRODUCTION AND OBJECTIVES

The purpose of this assessment is to examine specifically the current and potential risks

to human, ecological and ground and surface water receptors associated with possible

contamination of the ground at the site located at:


Alton

GU34 1RF

Ref: 470770,138210

The development proposal is for the renewal of extant permission 21068/032 – single

storey pavilion with bowling green and associated parking.

Evaluation of the risks is given and subsequently, if needed, recommendations made with

regard to further (Phase 2) investigation and/or remediation.

General guidance used:

BS 10175:2011 Investigation of potentially contaminated sites. British Standards

Institution, London.

CLR 11: Model procedures for the management of land contamination. Environment

Agency.

Environment Agency Guiding Principals for Land Contamination (GPLC).

(2010) Environment Agency.



2. SITE CHARACTERISATION AND FORMER INVESTIGATIONS

Current setting and condition (Drawing 1)

The site assessed for this investigation currently comprises 0.914 ha of land located on

Chawton Park Road, Alton. A road bounds the site to the north, with a girl-guide hut to

the east, a railway track to the south, tennis courts to the south-west and a cardiac

rehabilition building to the north-west (Photo 1). An open grassed area of land with trees

occupies the site (Photo 2). The site is approximately 1 m above the level of the road to

the north, with the topography of the site and surrounding land sloping down to the east.

The railway to the south is at a lower elevation in relation to the site.

Photo 1.(Aerial view)

Photo 2 (View from a road – NW to SE)



Site history (see Historical maps – Appendix A)

Land use Direction Distance (m) Notes

On-site

Undeveloped land with trees (pre 1873) On-site 0

Pavilion marked (1873-1973) On-site 0

Sports ground (1937-1973) On-site 0

Off site

Railway track (pre 1874-current) SE 4

Farm (pre 1874-1966) SE 124

Well (1896-1897) SE 128

Railway track (1910-1991) NE 123 Dismantled by 1991

Railway (1910-1992) SE 75

Former gravel pit (1937-1966) SE 154

Builders Yard (1966-1991) SE 154

Building developed c.2004 SW 1

Current soils, geology and hydrology

BGS maps indicate that the site is located on:

No superficial geology is recorded.

1:50 000 scale bedrock geology description: Holywell Nodular Chalk Formation - Chalk.

Sedimentary Bedrock formed approximately 89 to 100 million years ago in the

Cretaceous Period. Local environment previously dominated by warm chalk seas.

The closest BGS boreholes scans are 101 m west of the site;,

SU73NW40 — ALTON SPORTS CENTRE 2 (west of site) 470600,138061 Depth: 9.14m.

496410,191800 Depth: 747. Indicated: Topsoil over hard fissured chalk No groundwater was encountered. SU73NW39 — ALTON SPORTS CENTRE 1(west of site) 470580,138086 Depth: 9.14m

Indicated: Topsoil over hard fissured chalk No groundwater was encountered.



Flow to groundwater may occur through the soils to the aquifer at depth.

Surface water flow could find a possible route to surface water drains and channels to the

east leading to the Lavant Stream 267 m east of the site.

The site is on highly permeable Principal Bedrock aquifer and is not in a groundwater

source protection zone.

Zone II and Zone III of a groundwater source protection zone are situated 13 m north-

west.

Former investigations

No former investigations have been undertaken.



Current environmental data search

Environmental data (Appendix B) indicates the following:

The site is on a highly permeable Principal Bedrock aquifer

The site is not in a groundwater source protection zone.

No pollution inventory sites within 250 m

No waste treatment sites within 250 m

No pollution incidents within 250 m

No fuel sites within 250 m

No contemporary trade directory entries on site

No significant naturally elevated metal soil concentrations

No active landfill sites within 250 m

No historical landfill sites within 250 m

Radon is considered to be a risk (NE) as between 5-10% of homes are above the

action level for radon. Basic protection measures will need to be implemented in

the construction of new dwellings.

An inactive cardiac rehabilitation centre is listed 4 m south-west of the site.



3. CONCEPTUAL SITE MODEL

The conceptual site model detailed here is by a written and diagrammatical (Drawing 1)

description of the sources, pathways and receptors. A cross section is included if this will

aid interpretation.

3.1 Sources

Sources

Source location Direction Distance (m) Potential Contaminants

On-site

Radon On site (NE) 0

The property is in an intermediate

probability radon area, as between 5

and 10% of homes are above the

action level

Off site

Railway track (pre 1874-current) SE 4 Metals, hydrocarbons

Farm (pre 1874-1966) SE 124 Hydrocarbons, pesticides, herbicides

Well (1896-1897) SE 128 Methane, carbon dioxide

Railway track (1910-1991) NE 123 Metals, hydrocarbons

Railway (1910-1992) SE 75 Metals, hydrocarbons

Former gravel pit (1937-1966) SE 154 Methane, carbon dioxide

Builders Yard (1966-1991) SE 154 Metals, hydrocarbons, paints, solvents

3.2 Receptors

Humans

Residents and workers in the proposed development

Residents and workers in adjacent properties

Controlled waters

The site is on a highly permeable Principal Bedrock aquifer

The site is not in a groundwater source protection zone

Underlying aquifer

Ecology

● Animals and plants are considered to be possible receptors.

Buildings and services

Underground utility pipes



3.3 Pathways and plausible pollutant linkages (See Table 1)

Pathways to and from the site could exist via service channels.

Human health

The main pathways considered possible are:

1. Ingestion of soil

2. Ingestion of dust

3. Dermal contact with soil

4. Dermal contact with dust

5. Inhalation of fugitive soil dust

6. Inhalation of fugitive dust

7. Inhalation of vapours outside

8. Inhalation of vapours inside

9. Ingress to water supplies is also considered

Controlled waters

Flow to groundwater may occur through the soils to the aquifer at depth.

Surface water flow could find a possible route to surface water drains and channels to the

east leading to the Lavant Stream 267 m east of the site.

The site is on highly permeable Principal Bedrock aquifer and is not in a groundwater

source protection zone.



CSM Ref No. 1 Version a

SOURCE

TypeC urrent

workers

Fut ure

workers

D ev,ment

workers

C urrent

resident s

Fut ure

resident s

Ground

wat er

Surf ace

wat erEco logy

C urrent

workers

Fut ure

workers

D ev,ment

workers

C urrent

resident s

Fut ure

resident s

Ground

wat er

Surf ace

wat erEco logy

ON SITE

Radon Radon 1 N N N N Y N N N N N N N N N N N

OFF SITE

Metals 0 N N N N N N N N

Hydrocarbons 0 N N N N N N N N


Pesticides 0 N N N N N N N N

Herbicides 0 N N N N N N N N

Methane 0 N N N N N N N N

Carbon dioxide 0 N N N N N N N N

Metals 0 N N N N N N N N N/A


Methane 0 N N N N N N N N

Carbon dioxide 0 N N N N N N N N

Metals 0 N N N N N N N N


Paints 0 N N N N N N N N

Solvents 0 N N N N N N N N

For receptors and plausible linkages see Sections 3.2 and 3.3 of the report.

Notes

For risks from sources on-site and sources off-site see Section 4 of the report.

NA = not applicable

For sources and contaminants see Section 3.1 of the report.

TABLE 1. Plausible pollutant linkage/pathway matrix Y = yes, N = no, N/A = not applicable

RECEPTORS

On site Off sitePossible

present

1 yes, 0 no

Chemicals

Railway track

Former gravel pit

Former builders yard

Former farm

Former well

Former railway

tracks



4. RISK ASSESSMENT

4.1 Human health

No significant risks are considered to exist (Table 2).

Table 2. Risks from possible sources

Source location Direction Distance (m) Potential Contaminants Risk Reason

On-site

Radon On-site (NE) 0 Radon Yes 5 and 10% of properties are above the action level

Off site

Railway track (current) SE 4 Metals, hydrocarbons No Railway is at a lower elevation in relation to the site

Farm (pre 1874-1966) SE 124 Hydrocarbons, pesticides, herbicides No Natural attenuation, distance restricting pathways

Well (1896-1897) SE 128 Methane, carbon dioxide No Natural attenuation of ground gases

Railway track (1910-1991) NE 123 Metals, hydrocarbons No Distance and topography restricting pathways

Railway track (1910-1992) SE 75 Metals, hydrocarbons No Distance restricting pathways

Former gravel pit (1937-1966) SE 154 Methane, carbon dioxide No Natural attenuation, distance restricting pathways

Builders Yard (1966-1991) SE 154 Metals, hydrocarbons, paints, solvents No Distance restricting pathways

Notes:


Soil Environment Services Page 13 Final Report # 1

4.2 Controlled waters

No significant risk to groundwater or surface water is considered to exist as no

significant sources are considered to exist on the site and hence no plausible pollutant

linkages are present.

4.3 Ecology

No significant risk is considered to exist as no significant sources or receptors are

considered to exist on or within a significant distance of the site. Hence no plausible

pollutant linkages are present.

4.4 Buildings and services

No significant risk is considered to exist as no aggressive substances (e.g. acids, alkalis,

organic solvents, sulphates or chlorides) which may affects the building or plastic/metal

pipes are considered to exist on or within a significant distance of the site.


Soil Environment Services Page 14 Final Report # 1

5. UNCERTAINTIES AND PHASE 2 PROPOSALS

Basic radon protective measures are considered necessary in the construction of new

dwellings.

No other significant plausible pollutant linkages or significant uncertainties are

considered to exist.

Therefore no Phase 2 investigation is considered to be needed.

A watching brief should be conducted during development works. Should any evidence

of contamination become apparent, all development works must cease until further

investigation is conducted.

DRAWING 1

Current site location

NOTES:

Site boundary


Drawing number 1

Drawing title Site location plan

Scale 1:2500

Date 23/10/2013

N

APPENDIX A

Historical maps

APPENDIX B

Environmental data

Documents

CONTAMINATED LAND RISK ASSESSMENT - Vail …...Risk Assessment, Mineral Extraction Soil Planning The Nanotechnology Centre, Herschel Building, Kings Rd, Newcastle upon Tyne NE1 7RU