Hexavalent Chromium Treatment in low permeable soils
Ground Effects EK3 technology successfully treated and removed hexavalent chromium from low permeable soils to below detection limits over a 12 day period.
The Situation
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is used in textile dyes, wood preservation, anti corrosion products, chromate conversion products and a variety of niche uses. These industrial uses can lead to contamination of soil, surface and ground water. Traditional remediation strategies include, reducing toxicity through chemical or biological means, removal of the contamination (relocated the contamination to a landfill), and containment through engineered barriers. These options are often time consuming, expensive and other than removal, have limited long term success.
The Solution
Ground Effects has developed the EK3 technology that will remediate hexavalent chromium impacted soils, specifically low permeability soils in situ.
Due to the low permeability of soils, in situ treatment is cost effective and efficient. The EK3 utilizes both electroosmosis and electromigration principles to uniformly move nutrient reagent through these soils to infultrate, actively treat and remove the contaminants. Electroosmosis moves the solution from the anode to the cathode which aids in the movement of the contaminants from the soil. Electromigration occurs when the electrical field created causes the hexavalent chromium to move towards the negative electrode (cathode). Once collected, the contaminants can be extracted by vacuum extraction.
The Results
The EK uses DC current to reduce the concentration of hexavalent chromium to non detect levels within a 12 day period.
| Sample Number | Unit | Concentration | Percent (%) Removal |
|---|---|---|---|
| Sample 1 | mg/L | 0.263 | |
| Sample 2 | mg/L | 0.252 | 4 |
| Sample 3 | mg/L | 0.195 | 25.8 |
| Sample 4 | mg/L | 0.0317 | 87.9 |
| Sample 5 | mg/L | 0.000529 | 99.7 |
| Sample 6 | mg/L | 0.000373 | 99.8 |
| Sample 7 | mg/L | Not Detected | 100 |