Land Contamination Statement Upper Pulrose

Planning Application

Land Contamination Statement

For

Upper Pulrose Housing Re-development.

prepared for

Douglas Corporation

prepared by

Curtins Consulting Ltd 16th March 2010. Our Ref: 32492.016/IC/EF

Received: 10410 10/00/2010 DEPARTMENT OF INFRASTRUCTURE PLANNING AND BUILDING CONTROL DIVISION Town and County, Planninn Act 1999 Calle C. 100000 Initials Curtins Consulting Ltd

16th March 2010.

Our Ref: 32492.016/IC/EF

Page 1 of 6

1.0 Introduction

Curtins Consulting has been appointed by Douglas Corporation to act as Civil and Structural Design Engineers for the Upper Pulrose Housing Re-development Scheme.

The Upper Pulrose Housing scheme will create 195 new units through a mix of apartments, houses and sheltered flats. The works are to be phased starting with the lower section of the inner ring (phase 8) followed by the upper section of the inner ring (phase 9) and finally by the construction of the sheltered housing block situated on the central northern side of the outer ring (phase 10).

The proposed works will employ traditional forms of construction. The dwellings will have traditional concrete foundations, sub walls constructed in dense blockwork, superstructure walls constructed in cavity brickwork, timber floors and trussed rafter roof structures and solid concrete floors to the apartments and sheltered housing complex.

At the outset of the project a sub soil investigation report was commissioned. CC Geotechnical, Consulting Geotechnical and Geoenvironmental Engineers were appointed to conduct the sub soil investigation and to report on their findings giving recommendations for suitable foundations, floor slabs and pavement designs along with recommendations for dealing with contamination and environmental risks.

A comprehensive report was issued by CC Geotechnical referenced 09/5434 a copy of which is attached with this statement.

It is proposed to incorporate CC Geotechnical's report recommendations in the design of the Upper Pulrose Housing Re-development scheme as noted in section 5.0 of this land contamination statement.

2.0 Ground Investigation

Findings of the ground investigation are detailed in CC Geotechnical's report noted in the introduction. The inner ring sub soil conditions revealed minimal superficial drifts deposits. Topsoil was present at a number of positions to depths of up to 0.4 metres below ground level. Elsewhere the succession commenced with a thin layer of made ground extending to a maximum depth of 0.7 metres below ground level. Thereafter the succession was highly varied, comprising of varying depths of clay and gravel overlying bedrock.

Soil engineering testing was carried out to establish the soil moisture content and the particle size distribution.

Chemical laboratory testing was carried out to test for a broad range of contaminants including metals, semi metals, non metals, TPHCWG Hydrocarbons, Speciated PAH's TPH Banding and asbestos.

Each of the six soil samples subjected to broad spectrum chemical analysis was additionally subjected to soil leachate analysis.

Four samples of water obtained from monitoring installations were subjected to pH and sulphate analysis.

3.0 Site History

The site was originally farmland and was purchased by Douglas Corporation circa 1930. Lower Pulrose was already by this time developed for housing. The first houses in Upper Pulrose were occupied in October 1934.

4.0 Hydrology

The sub soil investigation revealed a varying groundwater regime prevailing at the site.

Minimal ground water flows were recorded during the investigation works undertaken to the areas of the site occupied by the existing residential housing estate with the exception of two occurrences one at TP3 at a level of 2.2 metres below ground level and BH 4 at a level of 2.6 metres below ground level.

In contrast, at the northern extreme of the site, investigations undertaken within the area of the site currently occupied by the playing fields revealed a water table standing at approximately $0.5-1.5$ metres below ground level.

These boreholes are to a degree remote from the site of the proposed sheltered housing complex which is more elevated than the location of these boreholes which were restricted in their location by the occupied dwellings on this section of the site and thus the results must be interpreted with this in mind.

5.0 Proposed Works

CC Geotechnical's recommendations will be implemented as follows: Gassing Regime

• Assessment of available data indicates that the site complies with characteristic situation 1, and as such does not require protective measures in the buildings

Soil Contamination

• The made ground within the vicinity of TP12 are impacted by elevated concentrations of PAH's and TPH'S.

TP12 was targeted within an area of former communal car parking garages and we believe the concentrations observed are due to historic fuel/oil leakage.

Remediation is required to mitigate potential risk to human health. It is recommended that the extent of impacted soils within the vicinity of TP12 is delineated by further soil sampling and analysis.

Once delineated it is recommended that impacted soils be excavated and removed off-site. Environmental Risk

• Leachates prepared from the made ground sample obtained from TP12 indicate potential leachability of PAH concentrations in excess of the UK DWS. However, given the absence of any known receptors the risk to controlled waters is considered negligible.