Dumbarton (Phase 2 combined site investigation, remediation strategy)
GeoEnvironmental was asked to carry out an environmental assessment on an old engineering site adjacent to a gas works in Dumbarton. A phase 1 assessment undertaken by another consultant identified that the site was likely to be highly contaminated so we combined a phase 2 investigation with the development of a remediation strategy for the site. The soils and groundwater were contaminated with petroleum hydrocarbons, creosols and phenols and the made ground formed a pathway to two receptors; the River Clyde and future residents of the site.
GeoEnvironmental derived a strategy which included a permeable reactive barrier to remove the risk associated with the migration of contaminated groundwater towards the river, this allowed the development of the site to continue whilst the groundwater was being remediated. A cap was placed over the site to break the link between the contamination and the residents. This had the added advantage of raising the site above the flooding level.
This strategy was agreed with the local authority as part of the planning permission for the development. The strategy was particularly beneficial to the client as the nature of the groundwater treatment meant that properties on the site could be occupied while the treatment was being undertaken. This allowed the developer to generate income for house sales early in the project.