Oakville PRB Installation Project
PERMEABLE REACTIVE BARRIER INSTALLATION
- LOCATION: Oakville, Ontario
- PROJECT VALUE: Approx. $790,000
- PROJECT TYPE: Permeable Reactive Barrier (PRB) Installation
- CLIENT: Confidential
- CONSULTANT: Confidential
- KEYWORDS: Decommission existing treatment system and install an advanced 68 metre PRB with zero valent iron (ZVI) to a depth of approximately 6.5 metres.
About this Project
A dated groundwater treatment system formerly operated at the property, which included a groundwater collection trench and sump designed to remediate elevated volatile organic compounds (VOCs) from the groundwater beneath the property. The project involved the full decommissioning of the existing groundwater treatment system and the construction and commissioning of a more complex and efficient ZVI PRB in its place.
Remediation Process
Nexxgen excavated a trench approximately 107 metres long by 1.2 metres wide to a depth of approximately 6.5 metres to remove the existing groundwater collection infrastructure. This was followed by the excavation of a new trench approximately 68 metres long by 0.9 metres wide to a depth of approximately 6.5 metres. Nexxgen then constructed, instrumented and commissioned a “pump and treat” system to remove/circulate and treat approximately 500,000 litres of groundwater which infiltrated the trench excavation structure throughout the duration of the project. Prior to installation of the PRB, Nexxgen activated their ISCO ECA with the regulatory authorities. The PRB installation media consisted of a predetermined ZVI mixture with concrete sand. This ZVI mixture was strategically placed across the stabilized groundwater interface from a depth of approximately 1 metre. The upper metre of the trench was backfilled with a coarse commercial granular material to grade and the area was resurfaced with asphalt.
The Outcome
The previous treatment system was removed and replaced. The current PRB trench continues to successfully remediate groundwater preventing off property migration of VOC contaminants.
