Todd Herrington

Global PetroFix Product Manager
REGENESIS

With 25 years in the industry, Mr. Herrington has an in-depth understanding of the complexities of in situ remediation, having evaluated or implemented mechanical, biological, and non-biological in situ remedial technologies at over a thousand sites. He thrives on collaborating with industry experts to generate innovative approaches to old problems, with a particular interest in colloidal technologies. He has been with Regenesis for nineteen years and before that spent six years at Parsons corporation. He graduated from the University of Cincinnati with an M.S. in Environmental Engineering and attained his Professional Engineer (P.E.) license in Colorado.

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Multi-Site Summary on the Effective Use of Colloidal Activated Carbon In Situ to Reach Site Closure for Hydrocarbon Sites

Colloidal activated carbon (CAC) is an emerging remediation amendment with a strong affinity for many toxic soil and groundwater contaminants. When combined with a destructive mechanism, it is possible to rapidly adsorb hydrocarbons onto the carbon particles, with degradation accomplished through biological or abiotic processes. We will summarize twenty recent projects across North America where an engineered mixture of CAC and electron acceptors achieved site closure at most sites, often within a year and a single injection. Typical for in-situ remediation projects, proper site characterization was a key contributor to success. It was also determined that documenting injectate distribution and making real-time design modifications, if needed, can significantly contribute to project success. Even with the best calculations and intentions, site variability is often best addressed by geochemical and observations tracer testing to perform real-time adjustments to injection variables (i.e., volumes) to reach design parameter targets leading to remedial success.