Permeable Reactive Barriers
Geo-Solutions is a leading installer of permeable reactive barrier walls (PRBs), a highly specialized type of slurry wall construction which is an economical alternative for applying chemical reagents to contaminated groundwater. PRB Walls are constructed as permeable barriers placed perpendicular to groundwater flow. They can be installed using the biopolymer slurry trenching (BP Trench) method, shallow soil mixing or conventional open-cut trenching. Our installation techniques permit the construction of PRB walls at depths of 70 feet or more even under high groundwater conditions. Geo-Solutions can install PRB walls in virtually any geology, usually without dewatering, use of sheeting, shoring, or the necessity of having personnel inside the trench.
Permeability of the application is controlled so that the PRB Wall exhibits a hydraulic conductivity similar to that of the surrounding native soils, allowing the groundwater to flow naturally through the barrier. Chemical reagents are added to the installation at the time of construction within the barrier or injected later through wells installed for that purpose.
Reagents typically placed using PRBs include zero-valent iron (ZVI), activated carbon, peat moss and many other customized remedial agents. Numerous groundwater contaminants can be addressed utilizing PRB technology, including:
- Volatile Organic Compounds
- Chlorinated Volatile Organic Compounds
- Light Non Aqueous Phase Liquids
- Dense Non Aqueous Phase Liquids
- Heavy Metals
The technology can also be utilized in concert with low permeability Vertical Barriers placed to direct groundwater flow through the PRB, commonly referred to as a "funnel and gate" system.
A Geo-Solutions PRB Wall installation results in an in-situ passive remediation system requiring almost no upkeep or maintenance. In most cases PRBs last decades as contaminants are degraded or absorbed. We have provided our clients with superior value engineering and ease of installation with the construction of PRBs nationwide.