Retirement apartment development – Surrey
Development detail: Construction of a three- to four-storey building comprising sheltered apartments for retirement-age residents
Roles: Providing assessment of existing data, supplementary environmental investigations and assessment, remediation options appraisal, monitoring and verification of remediation and liaison with regulators
This site had formerly been associated with a petrol filling station. When previous investigation work was reviewed, it was noted that groundwater had been impacted by petroleum hydrocarbons and there was also light non-aqueous phase liquid (LNAPL) – fuel sitting on the groundwater – present.
We were commissioned to provide an environmental assessment of the site, to identify potential pollutant linkages and to prepare a remediation options appraisal to remove, manage or mitigate any identified pollutant linkages.
Supplementary investigation and assessment was undertaken to enhance the existing data set for the site and it was possible, by using detailed quantitative risk assessment, to demonstrate that the ground conditions at the site were not an unacceptable risk to human health, controlled waters or other environmental receptors.
Whilst the LNAPL was identified as being static beneath the site, it was a potential future source that could increase dissolved concentrations of petroleum hydrocarbons in the groundwater. Monitoring over a period of two years (together with the pre-existing data for the site going back an additional six years) indicated that the LNAPL was diminishing but at a slow rate.
To provide an increased level of confidence against future unacceptable impaction of controlled waters, remediation was proposed to reduce the thickness of LNAPL present on the groundwater.
Crossfield Consulting was responsible for reviewing tenders and remediation designs by contractors to ensure that remediation objectives, agreed between Crossfield Consulting and the regulators, were met.
The proposed work ensured that there was confidence that a possible future liability for the client was removed and that the work undertaken was cost-effective compared to remediation works that had been proposed by others.
The regulators were kept informed and agreed with the proposals.
This project demonstrates that Crossfield Consulting can identify cost-effective solutions that still satisfy the requirements of regulatory authorities, permit economical development and negate potential future environmental liabilities.
Crossfield Consulting Limited
- The Granary,
White Hall Farm,
- +44 (1926) 815678
- +44 (1926) 815222