In-situ thermal remediation that injects pressurized steam into the subsurface to heat the formation, mobilize NAPL, and strip volatile contaminants into a recovered vapour and liquid stream. Most effective in permeable, saturated formations with chlorinated solvent or petroleum source zones.
Steam Enhanced Extraction injects saturated steam through dedicated wells, displacing groundwater and condensing into a thermal front that sweeps the formation. As the steam front advances, NAPL is mobilized toward extraction wells and dissolved contaminants are volatilized into the vapour stream for surface treatment. Target temperatures are typically 100 degrees Celsius, with some applications operating at slightly elevated pressure.
SEE is well suited to high-permeability, saturated formations with mass-rich source zones. It is faster than ERH or TCH when the geology cooperates, with treatment periods of 30 to 120 days. The technology requires careful hydraulic control to prevent uncontrolled NAPL migration, and finer-grained heterogeneity can leave untreated lenses that demand polishing by SVE, bioremediation, or chemical oxidation.
Also known as: SEE, steam injection, steam-enhanced extraction.
In-Situ Chemical Oxidation (ISCO): treatment approach
In-situ chemical oxidation: injection of a chemical oxidant — permanganate, persulfate, or Fenton's reagent — directly into contaminated soil or groundwater to destroy dissolved-phase organic contaminants without excavation.
An ex-situ soil treatment process that heats contaminated soil to volatilize and separate organic contaminants from the soil matrix, after which the liberated vapors are captured and treated, usually in a high-temperature oxidizer.
A thermal desorption configuration where the heat source contacts the soil directly inside the rotary unit, delivering high heat-transfer efficiency and supporting higher treatment temperatures.
A thermal desorption configuration where heat is conducted through the wall of the treatment vessel without combustion gases contacting the soil, producing a concentrated, lower-volume vapor stream suitable for condensation and recovery.
Treatment that heats contaminated soil and groundwater in place, typically with electrical resistance, thermal conduction, or steam injection, to volatilize and recover contaminants without excavation. Used where excavation is impractical or where the contaminant zone sits beneath active infrastructure.