CONTAMINANT TYPES and Site Applications
In Situ Thermal Remediation (ISTR) techniques, through reaching different levels of heating, will treat just about any organic compound, including:
- Polychlorinated biphenyls (PCBs), Polychlorinated dibenzodioxins and furans (PCDD/Fs), better known as simply Dioxins
- Polycyclic aromatic hydrocarbons (PAHs), often present in creosote at wood treatment sites, and coal tar at former Manufactured Gas Plant sites
- Trichloroethene (TCE), tetrachloroethene (PCE), 1,2-dichloroethene (1,2-DCE), trichloroethanes (TCA), and other halogenated hydrocarbons, often referred to as chlorinated solvents
- Pesticides and herbicides
- Petroleum, petroleum products and their volatile constituents including benzene, toluene, ethylbenzene, xylenes (BTEX), and methyl tertiary butyl ether (MTBE)
- Any other volatile or semi-volatile hydrocarbon
- Dense and light non-aqueous phase liquids (DNAPLs and LNAPLs)
- Nearly any other organic compounds or combination of organic compounds
Moderate temperatures (e.g., at or slightly above the boiling point of water, 100°C) can remove VOCs such as BTEX and Naphthalene from coal tar by steam distillation, which irreversibly changes the physical state of the remaining higher-boiling point Polycylic Aromatic Hydrocarbons (PAHs) from a liquid to a solid. This process, known as In Situ Thermochemical Solidification of coal tar (GTI, 2002), is very effective at halting the migration of coal tar DNAPL without excavation.
Applicable technologies: TCH, SEE, & ERH
Higher temperatures (e.g., 325°C) can be used to achieve destruction and extraction of SVOCs through vaporization, oxidation, and pyrolysis. Applicable SVOCs include PCBs, dioxins, PAHs, pesticides, and nitroaromatics. This approach has been proven to accomplish 95%-99% destruction of the SVOCs in situ, resulting in very low post-treatment concentrations in soil (e.g., for PCBs, <0.033 mg/kg; and for PAHs, <0.059 mg/kg of Benzo(a)pyrene toxic equivalents). Intermediate temperatures such as 200°C may be sufficient for treatment of lower-boiling SVOCs such as di- and tri-chlorobenzenes.
Applicable technologies: TCH only
Cascade Thermal’s technologies offer flexibility not only in the variety of contaminants that they can treat, but also in the applicability of the technologies to various site types.
Our thermal projects represent a wide variety of site applications including:
- Manufactured Gas Plants (MGP)
- Brownfields Redevelopment
- Fractured Rock Sites
- Beneath and Adjacent to Buildings and Infrastructure
- Rapid Site Cleanup for Closure and Resale