Case Studies - CA004 - Feroxsm

Military Base - Northern California

Recently, ARS completed the installation of a pilot scale Feroxsm system to treat deep TCE contamination at a military base in Northern California. Using a grid of 9 injection wells, ARS successfully emplaced 42,000 pounds of ZVI within the subsurface at the site. During injections, pressure influence at a distance of more than 100 feet 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 4-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 at the site presented several technical challenges for ARS due to its geology and depth. The drilling technique as specified by the prime contractor had to be changed and modified during the field application in response to certain obstacles imposed by the depth, running sand, and heterogeneous geologic conditions at the application zone.

View Feroxsm treatment zone diagram (13kb)

 

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