Lab Studies and Site Characterization for Permeable Reactive Barrier Walls
A complete and properly implemented site characterization is of critical importance for the design and installation of a reactive barrier. The plume location and extent, ground water flow direction, and contaminant concentrations must be accurately known to achieve the required performance. In addition, information on stratigraphic variations in permeability, fracturing, and aqueous geochemistry is needed. The plume must not pass over, under, or around the barrier and the reactive zone must reduce the contaminant to concentration goals without rapidly plugging with precipitates or becoming passivated. The barrier design, location, emplacement methodology, and estimated life expectancy are based on the site characterization information, therefore faulty information could jeopardize the entire remedial scenario.
In general, six aspects of site characterization should be evaluated before implementing a permeable reactive barrier. These are
- laboratory studies
- contaminant loading
- geochemistry, and when possible
When the site characterization has been completed, mapping and modeling can be carried out to determine the design and location of the permeable reactive barrier.