Steam Enhanced Extraction ("SEE") has proven a successful In
Situ Thermal Treatment method at multiple projects. The injection of
steam heats the soil and groundwater surrounding the injection well. The steam front transfers the latent heat of condensation from the steam to the adjacent soil and groundwater, until temperatures are reached to sustain steam throughout the entire treatment zone.
There are four main removal mechanisms at work during SEE operations:
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Contaminants (NAPL, in particular) are mobilized and made recoverable as a result of the reduction in viscosity and interfacial tensions.
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Contaminants are vaporized and extracted as off-gases.
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Contaminants are solubilized and removed in the dissolved state by the groundwater extraction system.
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Contaminants are destroyed in-situ via chemical reactions such as hydrolysis and dehydrohalogenation and possibly some biological reactions (to a lesser degree).
GEO's engineering team has experience designing, installing and operating SEE projects utilizing both vertical and horizontal, directionally-installed remediation wells. Both chlorinated and petroleum hydrocarbon VOCs and SVOCs have been addressed successfully with SEE sites in sandy, gravelly and porous lithologies.