In Situ Delivery (ISD™)
Anaerobic Bioremediation System
Anaerobic bioremediation is one of the most useful tools within the environmental industry. Anaerobic bioremediation is an effective method for degrading PCE, TCE, and other chlorinated solvents / contaminants (i.e. TCA, PCP, etc.) in soil and groundwater. More information about the science behind the chlorinated solvent remediation process is provided. Anaerobic bioremediation processes can also be used for other contaminants such as hexavalent chromium and pesticides.
While many electron donor substrate products are available today (sodium lactate, molasses, edible oils, etc.), the lack of effective application and delivery methods has often provided marginal results and/or extended remediation timeframes. Because of this, ETEC developed a series of automated delivery systems that accelerate in situ anaerobic bioremediation rates and ensure complete degradation on a site-wide basis. These systems have allowed our clients to successfully complete numerous anaerobic bioremediation projects.
The ISD™ Process
Extracted groundwater is amended with a soluble electron donor substrate and nutrients by our ISD™ equipment platform, which then injects this treatment water back into the subsurface. This consistent recirculation of electron donor-rich, nutrient-rich treatment water satisfies several critical requirements of anaerobic bioremediation, including:
- Constant delivery of a readily-degradable electron donor substrate to reduce native terminal electron acceptor mass and promote highly reductive conditions (i.e. sulfate-reducing or methanogenic) that encourage anaerobic bioremediation across a large plume area
- Continuous movement of the injected treatment water through the contaminated soil and groundwater for optimum contact with contaminants (PCE, TCE, DCE, etc.)
- Hydraulic plume control and the simultaneous production of localized groundwater gradients that deliver amended treatment water to specific zones within a plume area
- Explosive microbial growth within the pore space. After discontinuing groundwater circulation, this biomass will begin to “rot”, providing a long-term substrate to support ongoing anaerobic bioremediation. Site data has shown continued anaerobic for up to 24 months following cessation of groundwater recirculation