We think of Green as environmentally friendly, but this is not always the case. At a site in Exeter, an automotive dealer wished to develop a parcel of land that was affected by copper chrome arsenate, seen in the soil as a bright green residue. This compound can pollute groundwater, and as the site was located on a sand and gravel aquifer, a clean up operation was needed to discharge planning conditions.
Site remediation
When H Fraser Consulting Ltd (HFCL) became involved with the site, we realised that the source area was poorly defined and that clean up targets were too stringent to be realistically met. We undertook site investigation to delineate the source area and confirm groundwater quality. We then did a detailed quantitative risk assessment (DQRA) to derive remedial targets, using the Environment Agency’s Remedial Targets Methodology. The risk assessment took account of the engineered cover system that was proposed for the site, and the length of time that contamination would take to move through the aquifer. We defined the remediation objectives as the reduction of leaching of soil contamination to groundwater, to meet remedial targets, and the betterment of groundwater quality. Our Remediation Options Appraisal found that a combination of soil stabilisation with ongoing groundwater monitoring would best meet the remediation objectives, and we secured a remediation contractor to undertake the work. Having submitted a verification report for the remediation works, we are delighted that the work has been approved and the planning condition for remediation has been discharged.
The landowner is now able to use this well placed strip of land to show cars, and to develop the wider site in accordance with their planning permission.
Our work in the brownfield land sector
We understand that developers and landowners need to meet tough deadlines to keep their project on track. We provide:
- Phase 1 and 2 investigations
- Remediation Strategy Development and verification
- Specialist groundwater contamination services
Location: Exeter, Southwest
Dates: 2021 – 2024
