CA004 – Ferox™
Military Base, Northern California
ARS completed the installation of a pilot scale Ferox™ system to treat deep TCE contamination at a military base in Northern California. Using a grid of nine (9) injection wells, ARS successfully emplaced 42,000 lbs. of Zero-Valent Iron (ZVI) within the subsurface at the site. During injections, pressure influence at a distance of more than 100 ft. was observed. Sampling results four months after the injection have shown that TCE concentrations were reduced by as much as 82% from a maximum of 2100 ppb to 460 ppb within the center of the treatment zone. The majority of the monitoring points within the treatment zone have shown at least a 57% reduction in TCE levels within the four-month post-injection monitoring timeframe. Long-term monitoring is expected to assess the overall performance of the emplaced treatment system and the overall viability of ZVI technology at this depth.
Application presented several technical challenges for ARS due to the site’s geology and depth. The drilling technique as specified by the prime contractor had to be modified during the field application in response to certain obstacles imposed by the depth, running sand, and heterogeneous geologic conditions at the application zone.