CRS® (Chemical Reducing Solution) is an iron-based amendment for in situ chemical reduction (ISCR) of halogenated hydrocarbon contaminants such as chlorinated ethenes and ethanes. CRS is a pH neutral, liquid iron solution that is easily mixed with 3-D Microemulsion Factory Emulsified before injection into contaminated groundwater. CRS is a soluble, food-grade source of ferrous iron (Fe2+), designed to precipitate reduced iron sulfides, oxides, and/or hydroxides as shown in equation 1. These Fe2+ minerals are capable of destroying chlorinated solvents via chemical reduction pathways, thus improving the efficiency of the overall reductive dechlorination process by providing multiple pathways for contaminant degradation in groundwater.
The incorporation of iron as metallic particles or ferrous salts (Fe2+) can enhance chlorinated contaminant remediation by enabling various chemical reduction pathways. The overall combination of biological and chemical processes are referred to as “biogeochemical” reduction of contaminants. Biogeochemical reduction utilizes the biologically-generated reducing environment to create reduced iron precipitates that then go on to chemically reduce chlorinated solvents.
CRS is used in conjunction with 3-D Microemulsion to provide the necessary iron to activate abiotic chemical reduction (including the β-elimination pathway) of chlorinated organic groundwater contaminants like perchloroethene (PCE), trichloroethene (TCE), dichloroethene (DCE), and vinyl chloride (VC). The end products of these biogeochemical reductions are ethene and ethane.
For a complete listing of treatable contaminants please visit our Range of Treatable Contaminants Page.
If you currently have a project and need a remediation solution now, visit our Request a Design page.
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