Introduction
The Envirotreat Permeable Reactive Barrier System incorporates the use of modified pillared E-Clay technology. The E-Clay technology is designed to chemically immobilise pollutants of concern within contaminated groundwater.
The basis of the E-Clay barrier installation is to intercept the natural flow of contaminated groundwater. The barrier is unique in that it consists of the reactive material (pillared modified clay which is porous providing a permeable medium) mixed in-situ with the soils present. As the groundwater passes through the treatment barrier, the contaminants are immobilised within the media and are removed resulting in compliant groundwater.
The in-situ reactive barrier technology is recognised as a highly effective form of groundwater treatment. Envirotreat has demonstrated the ability of the barrier design to treat groundwater impacted with a wide range of pollutants, including hydrocarbon contamination (including total petroleum hydrocarbons, polycyclic aromatic hydrocarbons, chlorinated hydrocarbons, etc) and inorganics contamination (including metals, hexavalent chromium, cyanide, ammonium, etc).
Key Benefits
The key advantages of this technology are:-
- The barrier can be designed to effectively treat a wide range of inorganic / organic contaminants
- The barrier is designed to intercept the natural flow of groundwater and to have minimal impact on the overall groundwater regime
- The barrier is designed to be free from ongoing / future maintenance
- The barrier installation process is relatively quick,
- Installation is often on the site boundary and therefore releasing the site for other works
- Process recognised and accepted by the regulators
- Accepted / demonstrated that installation has negligible effect of permeability, negating the need for complex groundwater modelling
- Cost effective solution to pervasive groundwater contamination
- Can be used to compliment source treatment in an integrated approach or as a stand alone strategy
Barrier design.
The E-Clay Permeable Reactive Barrier is designed to meet client / Regulator requirements in terms of lifespan and remediation criteria. Existing Site Investigation findings are adequate for most site barrier designs.
Barrier installation.
Envirotreat utilise two different installation approaches.
The first approach uses Continuous Flight Auger soil mixing technology (Piling Rig) to soil mix the in-situ soils with the E-Clay medium and create a barrier by overlapping soil mixed column to produce the E-Clay barrier.
The second approaches uses a conventional excavator to create a series of short interlocking trench sections where the soils are mixed in-situ soils with the E-Clay medium.
