CLIENT:
Bayview Developments (South) Ltd

DATE OF PROJECT:
February 2016 to July 2018

LOCATION:
Alderholt, Dorset

BUSINESS SECTORS:
Private Sector Residential Development

SERVICES PROVIDED:

  • Intrusive Investigation (boreholes and trial pits)
  • Ground Gas Monitoring
  • Groundwater Monitoring and Sampling
  • Chemical Laboratory Testing
  • Contaminated Land Risk Assessment
  • Controlled Waters Risk Assessment
  • Ground Gas Risk Assessment.

PROJECT BACKGROUND

The site had formerly been part of quarry works, with subsequent unlicensed landfilling. More recently it was used as a surplus stores, with small scale car workshops present. Due to the historic industrial use of the site it was considered the site posed a significant risk to human health. Controlled waters and further investigation was required to allow a detailed remediation strategy to be produced for the prospective developer.

PROJECT OBJECTIVES

To provide geoscience services to assist in the discharge of the contaminated land planning condition. Several phases of site investigation had been carried out more than 10 years previously., This data was required to be reviewed, compiled and updated to assist in the discharge of the planning condition.

OUR ROLE

ACS initially undertook further intrusive investigation. This comprised of 22 trial pits and chemical analysis of underlying soils to determine the level of contamination on site. Existing boreholes from previous investigations were used to get an initial insight into ground gas and ground water conditions.

Following the initial investigation, ACS undertook further intrusive site investigation. Installation of 5 ground gas monitoring wells and 3 groundwater monitoring wells allowed further ground gas and groundwater risk assessment. ACS were required to submit the findings of the investigation to both the Local Authority and Environment Agency for approval.

Following approval of the risk assessment for the site, ACS produced a remedial strategy. The strategy allowed the pre-commencement contaminated land planning condition to be discharged.

CHALLENGES

The investigation required detailed review of two previous investigations for the site which were undertaken between 2005 and 2015. All results from the historic investigations and current ACS investigations were compiled. This built a more complete picture of both ground conditions and contamination across the site.

The site had a number of contaminative land uses including un-recorded landfilling. This posed difficulties in assessing the nature of contamination.

The geology underlying the site was complex with interbedded sands and clays of the Poole Formation recorded. Therefore, monitoring of groundwater within each bore hole had to be carefully assessed to identify which geological unit the sampled groundwater was associated with.

CONTACT

Adam Dean
E: adam.dean@acstesting.co.uk
T: 01202 628649

Anthony Elkins
E: anthony.elkins@acstesting.co.uk
T: 01202 628647