At the 2025 Alaska Forum on the Environment, Benoît, who is a Senior Engineer at Savron, a Geosyntec Company, will present on the successful use of STAR smoldering remediation technology in Alaska. He will speak on Wednesday, February 5, during the session, “PFAS Soil Remediation Success Stories.”
Q&A
What is Savron’s STAR technology?
STAR stands for self-sustaining treatment for active remediation. It uses smoldering combustion, which is flameless and happens on the surface of a fuel, to destroy contaminants. This is in contrast to flaming combustion, which occurs in the gas phase. A good way to imagine what this looks like is to picture glowing charcoal briquettes in your grill and how they continue to burn and produce heat without additional fuel being added.
Treated soil plots planted with native grass mix and left open to the elements after 7 weeks (Left to right): Unamended soil control, compost-amended, and fertilizer-amended all supported plant growth.
How was STAR developed and what advantages does it have over traditional remediation methods?
The technology was first developed by a group of researchers who are experts in smoldering combustion. They saw the potential for real-world remediation applications, especially in the oil and gas industry. We’ve partnered with universities and have our own combustion lab in Cambridge, Ontario. Our first full-scale project was in situ, meaning we smolder underground without digging up the soil, which is unique.
The major advantage of smoldering combustion is how low the energy input is for the heat we generate.
We initiate the reaction by targeting a zone of the fuel to start the process, and once it starts, we only provide more air to sustain it, without applying additional heat. It’s very energy efficient. For instance, if I have a system that operates for seven days, we only have to heat it for one day, and the rest of the time, we’re just providing air for the combustion to sustain itself.
Compare that to an incinerator, which needs to run all the time, with heat constantly being applied. As a result, STAR is extremely efficient per unit of treated material. It’s also resilient. We can have a power outage and afterward flip the breakers back on and restart combustion with minimal input because there’s so much heat left in the soil.
We’ve also developed large plants for ex situ remediation, and we recognized the need for a mobile system. This need led to the development of the STARxpress System, which we first implemented in Alaska at Joint Base Elmendorf-Richardson (JBER).
What types of contamination is STAR best suited to address?
We originally focused on the oil and gas industry. The STAR technology does well with very heavy hydrocarbon-type fuels, like coal tars or weathered oil. We’re particularly well suited for oil and gas terminals or transfer stations. Many times, these fuels are already mixed with sand, which is needed for combustion. A contaminated soil pile might look like very dark black sand, and by the time we finish treating it, it looks like beach sand. To implement STAR in situ, we can install wells directly into the contaminated area, even if that area is under the water table, so STAR can be particularly useful in places where digging up the soil is logistically difficult or cost-prohibitive.
Smoldering remediation can be applied to basically anything that needs a high temperature to be destroyed, including contaminants like PFAS.
The reason that PFAS is so difficult to get rid of is because it’s super stable and needs a lot of energy to be destroyed. With smoldering, we can achieve high enough temperatures in the soil itself to efficiently destroy any PFAS that’s present.
Last summer, we wrapped up field operations for a project also at JBER in Alaska where we used our new mobile STARxpress System to treat PFAS-impacted soils. This mobile ex situ treatment system essentially looks like three shipping containers: two treatment units and a control container. The JBER project was part of a Defense Innovation Unit demonstration to showcase ready-for-market technologies to treat PFAS. Within 13 months of starting the project, Savron completed the design, fabricated the STARxpress System, shipped everything to JBER, and treated 440 yards of PFAS-impacted soil.
Are there any specific considerations that work in Alaska?
The cold climate does present challenges. On top of general equipment considerations, it all comes down to an energy balance for smoldering. We are still researching how the in situ method can be applied in a permafrost zone. With ex situ, you can control more variables, but there are many locations where it doesn’t make sense to dig, for example, because the target is under the water table. In those situations, our in situ approach can be ideal.
Treated soil being unloaded from the STARxpress System, Savron’s new mobile treatment system.
How does smoldering remediation affect the future use of a site?
We frequently get asked about the post-treatment condition of the soil. Smoldering destroys organic matter and microbes but maintains the soil’s geotechnical properties. So, we’ve found that once the soil cools, adding amendments like fertilizer and compost renders the soil completely usable. Our project at JBER included a plant study that showed amended post-treatment soil could easily support plant growth.
How can this technology benefit clients in Alaska?
Alaska has a high number of remote locations with challenging logistics. as our Anchorage office can attest. Our mobile STARxpress System can travel to sites and treat stockpiles, avoiding the need for shipping soil elsewhere. We can roll up with our gear and help clients treat the soil at the site, and the treated soil remains on site for future use.
About the Speaker
Benoît is a Senior Engineer at Savron, a Geosyntec Company. He brings 10 years of experience focusing on energy transfer and energy production systems and helped develop and implement Savron’s STAR remediation soil treatment solutions.
About Savron
Savron, a Geosyntec Company, is a multinational provider of sustainable waste management and remediation solutions, specializing in the safe, energy-efficient treatment of a broad range of hazardous materials.
More Information
For more information about Savron’s STAR remediation technology, contact Benoit Boulay at bboulay@savronsolutions.com.
Learn about STAR: Savron’s In Situ Smoldering Combustion Solution.
Learn more about Savron at www.savronsolutions.com.
