In Situ Sorption and Biodegradation

At a Glance


Contaminants are adsorbed onto activated carbon to halt migration and/or promote subsequent biodegradation

Treatable Contaminants

Treats a wide range of contaminants,
including chlorinated solvents, petroleum, and PFAS


Addresses low to moderate concentrations


Rapid results (days)


Works in saturated and unsaturated zones

Applications Frequency

Effective after a single application

In Situ Sorption and Biodegradation Overview

In situ sorption involves the injection or direct mixing of activated carbon into groundwater and soil for the primary purpose of rapid removal of contaminants from the mobile phase. Sorption via activated carbon is a powerful approach that is most often deployed to achieve complete remediation at sites characterized by low-level, lingering contamination; address back diffusion of contaminants emerging out of low permeability zones; or reach stringent cleanup targets quickly.

Typical results using colloidal activated carbon
Typical results from a REGENESIS in situ sorption and biodegradation project. PFAS and PCE contaminants are reduced to non-detect within days. Dotted lines are upgradient (non-treated) monitoring wells.

To achieve successful results using sorption, REGENESIS has developed technologies using colloidal activated carbon. This is activated carbon that is milled down to 1-2 microns (most granular activated carbon used for remediation is 1,000 microns in size). In the case of PlumeStop Liquid Activated Carbon, it is suspended in water using advanced polymer chemistry. As a result of their colloidal properties, all REGENESIS activated carbon products, including PlumeStop and PetroFix Remediation Fluid, distribute in situ under low pressure injection, and achieve very rapid sorption of contaminants.

Once the colloidal activated carbon has been applied in the subsurface, the sorbed contaminants are removed from the mobile phase and can then be treated to promote enhanced biodegradation. When using PlumeStop to treat chlorinated compounds, this strategy is often combined with other technologies such as 3DME, HRC or S-MicroZVI to promote enhanced biodegradation or chemical reduction of contaminants. When using PlumeStop to treat petroleum hydrocarbons, the activated carbon is often combined with ORC Advanced and/or our ISCO amendments to biodegrade or oxidize contaminants.

In situ sorption can also be used as a stand-alone tactic without biodegrading contaminants. This remediation approach is often strategically selected when dealing with contaminants that do not readily degrade, such as PFAS compounds. Using this approach, PFAS plumes can be sequestered so that they do not impact sensitive receptors. Because colloidal activated carbon injections represent a small fraction of the cost when compared to alternative carbon pump and treat methods, PlumeStop is often selected at PFAS sites to remove risk rapidly and cost-effectively.

PetroFix Remediation Fluid offers an approach to treat petroleum contaminants quickly and effectively using in situ sorption and biodegradation. PetroFix removes hydrocarbons from the dissolved phase by adsorbing them on to the micron-scale activated carbon particles and then stimulates hydrocarbon biodegradation by adding electron acceptors.

REGENESIS welcomes the opportunity to provide you and your team with the tools you need to successfully plan and execute your next sorption and biodegradation project.

If you currently have a project and need a remediation solution now, request a design.

Have questions or want to explore some ideas? Contact Us to get in touch with a local representative.

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