For every zone of your plume, we’ve got you covered!

Leaders in Remediation of Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS)

Interested in a Site Evaluation? 

Let our Experienced Technical Service Team assist you with a no charge evaluation of your site.

Learn More


- Enhances Efficiency

- Minimizes Methane Production

Learn More

Electron Donor

Solutions for


Reductive Dechlorination

Formulating Surfactant Blends

Learn More

Tersus hosts Technology Lecture Series on groundwater remediation at multiple cities 

across the US


Accelerating Natural Attenuation of Petroluem Hydrocarbons

Additive injection and groundwater recirculation trailers available for short or long term lease.

TersOx™ - Inorganic Peroxygen for Enhanced Aerobic Bioremediation

RemBind designed to treat TPH, PAH, PFOS, PCBs, PCPs, and various pesticides

Sulfate Enhanced Bioremediation 

RemBind™ Prominent at the 2016 Battelle Remediation Conference

RemBind™ was prominent at the 10th International Conference on the Remediation of Chlorinated and Recalcitrant Compounds held in Palm Springs, California from May 22nd to 25th, 2016. Dr Richard Stewart gave a platform presentation on the ability of RemBind to outperform activated carbon in binding per- and polyfluorinated alkyl substances (PFAS).

Ziltek also presented a poster with BECA showing that RemBind™ successfully treated wastewater from an airport training ground in Australia. Two other posters on the use of RemBind™ to treat PFAS compounds were also presented by Tersus Associates.

If you would like copies of these presentations, please contact us for further information.

Pictured: (L-R) Gary Birk, Sherri Scott, Aaron Archibald and Mark Kluger

Self-Nano Emulsion; Advanced Electron Donor Delivery for Enhanced Anaerobic Bioremediation

U.S. Patent and Trademark Office Awards Tersus Patent for Self-Nanoemulsifying Oil

Research Triangle Park, NC, April 29, 2016 – Tersus Environmental announced today that the United States Patent and Trademark Office granted a patent for soil or groundwater remediation using a self-nanoemulsifying oil. The issuance of this patent further validates the innovative nature of Tersus’ electron donor technology platform and family of biotechnology-based solutions to manage complex, challenging environmental liabilities.

Officially granted on April 12, 2016, the U.S. patent number for bioremediation of soil and groundwater is #9,309,136 B2. The patent application was filed on June 12, 2014 (14/120,646) by Tersus Partners John Archibald, P.Eng and Gary M. Birk, P.E.

Nanoemulsions are a class of emulsions with droplet sizes typically ranging between 50 and 500 nanometers (1,000 nanometer = 1 micron). Common methods for producing nanoemulsions utilize high-shear mixers or high-pressure homogenization. Tersus’ spontaneous emulsification is an energy efficient alternative which is ideal for site remediation operations and less expensive. This innovative approach is actually a very energy efficient process, taking advantage of the chemical energy stored in the system. The small size of the particles in a Self-Nano Emulsion delivery system offers a number of benefits including improved subsurface distribution, enhanced long-term stability and increased bioavailability.

Florida DEP Approves NutriBind™ as part of its Innovative Technologies Acceptance Program

Research Triangle Park, NC, April 28, 2016 – Tersus recieves approval from the Florida Department of Environmental Protection (FDEP), accepting the use of NutriBind™ as an innovative technology in the treatment of contaminated soil and groundwater. While the Florida DEP does not provide brand name endorsements or performance certifications, it does determine product acceptability in the context of environmental regulations, safety and the protection of public health. These approval letters make it easier for Remediation Project Managers to specify Tersus products in site-specific Remedial Action Plans.

Emerging Contaminants: PFAS Update

Ex Situ Treatment of Aqueous Film-Forming Foam Impacted Groundwater

March 10, 2016 — Perfluoroalkyl and Polyfluoroalkyl Substances (PFASs) are common in Aqueous Film Forming Foams (AFFF) used for firefighting. PFASs are widely distributed across the higher trophic levels and are found in air, soil and groundwater at sites across the U.S. (EPA 505-F-14-001, March 2014). The toxicity, mobility and bioaccumulation potential of PFASs pose potential adverse effects for the environment and human health. They are persistent in the environment, among the strongest organic compounds and thus considered non-degradable.

Practitioners have difficulty remediating these compounds at a reasonable cost because PFASs tend to be highly soluble, do not favorably partition into the vapor phase, and do not adsorb well to granular activated carbon (GAC). To date, GAC has been the only technically feasible method to treat PFAS-aqueous media.

PerfluorAd followed by RemBind polishing is an innovative process for the treatment of PFAS contaminants in AFFF-aqueous media. Fortunately, the costs for PerfluorAd RemBind treatment train are very favorable compared to activated carbon or ion exchange systems. And, unlike activated carbon, this approach works well for the removal of short-chain PFASs.

In the pretreatment phase, PFASs are precipitated by metering the liquid PerfluorAd active compound into a stirring tank. The amount of PerfluorAd can be adjusted to varying concentrations. The precipitation products are separated from the water as micro-flocks by simple processes such as sedimentation and filtration. The precipitants can be concentrated to a very high degree, which allows for very economical disposal as compared to GAC. Post-treatment of the remaining residual contaminants is performed by a downstream RemBind filter. Due to the significant reduction in the PFAS-contaminated water in the PerfluorAd stage (up to 90%), the PFAS contaminant load reaching the absorbent filter(s) is lowered, which leads to a significant extension of the absorber’s lifetime, again significantly lowering operating costs.

As the technology is new to North America, Tersus Environmental is seeking pilot demonstration sites. Please contact a Tersus representative.

Giving Thanks

During this month of Thanksgiving I have been reflecting on the things I am most grateful for.  Primarily among them is our talented group of associates and business partners across the globe.  I consider myself extremely blessed to be a part of Tersus since its inception.  It’s been my home away from home. 

We have a great Team that celebrates and supports each other – through the good times and bad.  I am immensely proud of our associates and their desire to further engage and to deepen our relationships so that we can all grow together.  We bring care and passion to the table every day, and even when the occasional disagreement arises, we always come back together as Family.

I am also proud to see how our associates and business partners are happy, engaged, inspired and driven to take care of the ones that make this all possible, our clients.  Without our clients, there is no Tersus.  So on behalf of the entire Tersus family, I’d like to thank our clients for offering us the opportunity to provide technology-based solutions to manage complex, challenging environmental liabilities and reduce costs for site closure.

It’s an honor to be a part of this Team and to work with our associates and business partners in serving, our clients. I wish you a Thanksgiving filled with abundance and bright moments.


Gary M. Birk, P.E.
Managing Partner, Tersus Environmental

The Use of Tersus Marketed eZVI for Soil & Groundwater Remediation Is Not ZVI Patent Infringement


Letter from ‘709 Patent Holder

Currently, there is some confusion and uncertainty about whether the use of eZVI for soil and groundwater remediation infringes on U.S. Patent 7,531,709 (“the ‘709 patent”) titled Method for Accelerated Dechlorination of Matter. While some of you may have received notices (either oral or written) alleging that any use of ZVI plus soybean oil for soil and groundwater remediation infringes the ’709 patent, we are certain that the eZVI marketed by Tersus Environmental does not infringe on the ‘709 patent.

Tersus Environmental respects the intellectual property of others and would not intentionally promote the use of any methods or techniques which infringe a valid and enforceable patent. Further, as practitioners, you must be free to choose the appropriate methods of remediation without fear of unjustified claims of infringement or litigation. 

The eZVI patent application was filed on October 2, 2001, 461 days prior to the ‘709 patent priority date. Further, National Aeronautics and Space Administration (NASA) was granted U.S Patent 6,664,298 titled Zero-Metal Emulsion for Reduction of Dehalogenation of DNAPLS on December 16, 2003, 1,974 days (5.4 years) prior to issuance of the ‘709 patent.

The simple answer is this:  The use of Tersus eZVI product does not infringe on the ‘709 patent.

*eZVI is a NASA developed and patented technology, U.S. Patent Application Nos. 6,664,298 and 7,037,946.  eZVI is sold under License Agreement No. DN-1205 between NASA and Tersus Environrmntal.  

All Zero-Valent Iron (ZVI) Remediation Products ARE NOT THE SAME

The MAJOR DIFFERENCE between Emulsified Zero-Valent Iron (eZVI) and other ZVI products is the physical structure of the eZVI product, which is a water-in-oil emulsion (see below images). This structure makes the eZVI product hydrophobic, and therefore it is fully miscible with source material in situ. The water contained in the interior of the eZVI emulsion provides the hydrogen for abiotic reductive dechlorination reactions to proceed. Without a hydrogen donor, abiotic reactions that occur on the surfaces of the ZVI particles will not proceed.  If you are implementing a source area remediation and using the eZVI technology, make sure that your product supplier can document the micellular structure and hydrophobic chemistry of their EZVI product.  Please note that a combination of ZVI and emulsified oil (oil in water emulsion) WILL NOT provide the benefits that our eZVI product enables.  The physical structure of the eZVI emulsion is the key to sustaining dramatic source area mass flux abatement and direct abiotic destruction of source mass, while simultaneously stimulating microbiological processes to destroy dissolved phase contaminants. 

EZVI Physical Structure

Due to the unique (patented) physical structure of eZVI, the ZVI component of the emulsion is protected inside of a hydrophobic membrane (see image above), and unlike any other ZVI products, this enables the ZVI to efficiently target the destruction of chlorinated hydrocarbons (e.g., contaminants that have the appropriate hydrophobic physical chemistry to pass through the vegetable oil membrane and contact the ZVI). Another significant difference between the technologies is the fact that eZVI takes advantage of the physical chemistry of the contaminant, and sequesters it within the vegetable oil membrane surrounding each micelle (see above images). The sequestering of contaminants into the vegetable oil membrane results in significantly reduced aqueous contaminant concentrations (~ 90% decrease), and therefore decreased mass flux from the source area. Contaminants that have phase partitioned into the vegetable oil layer then begin dissolving/diffusing into the aqueous interior of the micelle where they contact the ZVI and are destroyed (completely dechlorinated to ethane). A concentration gradient is established and the contamination is continually pulled toward the interior of the micelle where it abiotically dechlorinated. While both technologies utilize the same chemistries, eZVI is engineered to directly remediate source areas by taking advantage of the physical chemistry of the contaminant(s) and optimizing the role of abiotic reactions, which DO NOT create problematic daughter intermediates.

eZVI Miscible with DNAP

In addition to the above abiotic reactions, the vegetable oil membrane associated with the eZVI is a fermentable carbon source and therefore acts as an electron donor for biostimulation downgradient of the eZVI injection area(s). With eZVI you get a one-two punch; (1) optimized abiotic reactions along with (2) the polishing effects of anaerobic bioremediation processes. Target the use of your ZVI. Do not be fooled into thinking that injection of ZVI and a carbon substrate (e.g., vegetable oil, lactates, fatty acids, plant fibers) is the same as using eZVI. Our eZVI is the superior choice when remediating sites with source areas/DNAPL zones (residual or pooled).

Talk copy

To learn more about eZVI or arrange a One to One with your local Technical Sales Representative, contact us today.
*eZVI is a NASA developed and patented technology, U.S. Patent Application Nos. 6,664,298 and 7,037,946.  eZVI is sold under License Agreement No. DN-1205 between NASA and Tersus Environrmntal.

Tersus Environmental Signs Sales and Distribution Agreement with Ziltek Pty Ltd

Distributor Agreement Brings Chemical Fixation / Immobilization Technology to Tersus’ Portfolio of In Situ Soil and Groundwater Remediation Technologies

Wake Forest, NC – March  2015 – Tersus Environmental, LLC, a rapidly growing developer and marketer of advanced, innovative technologies for the remediation of soil and groundwater, and Ziltek Pty Ltd, Adelaide, Australia are pleased to announce that the two firms have entered in an agreement wherein Tersus is appointed the North American exclusive distributor for the RemBind™ product. RemBind™ is a unique powdered reagent that binds and immobilizes contaminants in in soils and sediments.  RemBind™ treats a broad range of organics including PFOS, PFOA, PCBs, PCPs, PAHs, TPH, various pesticides and heavy metals such as arsenic, chromium and mercury.

Gary M. Birk, PE Managing Partner with Tersus said, “We are very pleased about the opportunity to partner with Ziltek.  This agreement will facilitate a sizable expansion for Tersus into the soils and sediment remediation market.  The breadth of the emerging contaminants that are amenable for treatment with RemBind™ will further enhance our leadership position in the remediation market sector.  RemBind™ is a quality product for immobilization of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA) and a great addition to Tersus’ suite of superior technologies and products.”

“Tersus has a stellar reputation and is a recognized leader in bringing new technologies and applications to the forefront in the environmental remediation community,” said Chris Lawrence, Ziltek Commercial Manager.  “Our goal is to reach as many contaminated site owners as possible that will benefit from RemBind™. Our relationship with Tersus will allow us to further the realization of that goal.”


Technology Update: Ethoxylated Surfactants and 1,4-Dioxane Point of Interest!

Ethoxylated Polysorbate Surfactants and Why we Do Not Use Them

Many surfactants that have US FDA Direct Food Additive status are ethoxylated.  Anytime you have an ingredient on your food label that says “polysorbate”, that’s an ethoxylated surfactant. The polysorbate surfactants are made by reacting fatty acids with a sugar molecule, then adding a polyethylene oxide chain to make it more water-soluble.

As you may know, many environmental remediation injectates, such as emulsified vegetable oil and NAPL solubilization compounds, use biodegradable, non-ionic surfactants. ESTCP 2006 and AFCEE 2007 teach how to make emulsified vegetable oil (EVO) for bioremediation using polysorbate, an ethoxylated surfactant.  In Appendix H.2, AFCEE 2007 discloses the formula for an EVO product and lists polysorbate as one of the ingredients.

Unfortunately, ethoxylation, the manufacturing process that creates these surfactants (e.g., polysorbates) often results in these products containing 1,4-dioxane.  While the FDA has set a limit on 1,4-dioxane at 10 ppm in polysorbates, glycerides and triglycerides, this limit is well above California’s notification level of 1 µg/L for drinking water (CDPH 2011). As a result, we do not use any of these surfactants in our vegetable oil based electron donor (EDS-ER™) or our TASK™ family of surfactants for NAPL recovery.

Tersus EDS-ER does not conatin 1,4-dioxane.

Lecture Series – Soil & Groundwater Remediation Technology

01/17/2015 – 12/31/2015

various – see website link below for details

Tersus is co-hosting this national remediation lecture series on soil and groundwater remediation technologies.

Our Technology Lecture Series brings a half-day of technical presentations on soil and groundwater remediation by a number of professionals from various organizations. These educational seminars bring together scientists, engineers, regulators, site managers and other environmental professionals from government, academia, service and R&D firms to advance the state-of-the-practice.

We know that NOT all educational events are created equal. We have worked hard to recruit both unique and impressive speakers to make the most of your valuable time. At our seminars you will connect directly with industry leading practitioners as they highlight the latest ideas for contaminant source area delineation, bioremediation and sustainable remediation technologies. You won’t want to miss this seminar!

Tersus and our partners offer these seminars at No Cost to our clients and guests from within the groundwater remediation community. Each seminar includes lunch and a certificate for 4 hours of Continuing Education. Seating for these private events is limited and you must register to attend.

Current locations are listed below:

  • Atlanta, GA – February 17th
  • Greenville, SC – February 18th
  • Charlotte, NC – February 19th
  • Santa Ana, CA – March 4th
  • Oakland, CA – March 5th
  • Portland, OR – March 31st
  • Seattle, WA – April 1st
  • St. Louis, MO – May 5th
  • Chicago, IL – May 6th
  • Minneapolis/St Paul – May 7th
  • Indianapolis, IN – June 2nd
  • Columbus, OH – June 3rd
  • Detroit, MI – June 4th
  • Tampa, FL – September 1st
  • Raleigh, NC – September 15th
  • Denver, CO – September 23rd