New Process Filters Water Contaminants.

• Position: Brief Article

A technique developed at the Department of Energy's Pacific Northwest National Laboratory, Richland, Wash., may be able to remove deadly contaminants from groundwater more easily and less expensively. In-Situ Redox Manipulation (ISRM) treats contaminated groundwater at up to 60% savings over 10 years when compared to current methods. Potential application sites include military bases, petroleum and chemical plants, and weapon production facilities.

ISRM could address the growing concern surrounding chromate--a contaminant found near metal-plating production sites, automobile production plants, and military bases. Chromate can be toxic to fish and humans.

The process is an improvement upon current remediation techniques. In the widely used pump-and-treat method, contaminated water is withdrawn through wells, purified at water treatment plants, then injected back into the ground. However, it is costly to drill wells, build a special treatment facility, and perform long-term operation and maintenance.

Another method involves digging trenches to act as barriers. The trenches are filled with iron particles that react with and filter contaminants, but cannot be dug deep enough to reach groundwater in many locations.

ISRM uses a standard six-inch groundwater well and does not require building permanent structures. It is conducted below the surface, therefore decreasing risk of exposure to workers. Additional benefits include its...