Solutions for the in-situ soil remediation - Soil and Groundwater - Site Remediation

For over twenty years, BioSolve Pinkwater has been used for Surfactant Enhanced Remediation (SER) to mobilize and solubilize residual NAPL[i], facilitating its recovery and disposal. Depending on soil and plume characteristics, Pinkwater solution can reach contaminated zones through deep injection wells or be gravity fed from surface level injection galleries. After desorbing residual NAPL from soil surfaces on contact, Pinkwater then solubilizes the hydrocarbons in an aqueous emulsion, enabling extraction at down gradient recovery wells or trenches.

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Each in-situ soil remediation site has a unique history and set of challenges requiring a customized solution. Pinkwater is particularly effective where there are relatively homogeneous subsurface conditions, soil porosity of at least 20%, and hydraulic conductivity of 10-3 cm/s or greater. A thorough subsurface soil characterization is generally necessary before the injection and recovery plan can be developed.

Pinkwater is frequently used as part of a multi-phase remediation program. Sufactant injections may be preceded by an extended period of 'pump and treat' and for dual phase vacuum extraction and followed by chemical oxidation. In all cases, responsible treatment/disposal of effluent (which contains emulsified hydrocarbons) is a key part of project design.

Objective

  • To remediate underground soil contaminated by NAPL as part of a project to achieve site closure and comply with local groundwater standards.
  • NAPL that is trapped in the subsurface is mobilized and removed by aggressively flushing the contaminated soil with surfactant solution.

Advantages & Benefits

  • Pinkwater, in a dilute solution of 2% to 5%, is easy to work with. Standard procedures are available to treat recovered effluent.
  • Surfactant “breakthrough” and success in hydrocarbon recovery can be readily monitored by periodically examining test samples of effluent during extraction.
  • With the infrastructure of “pump and treat” already in place, surfactant flush is a logical next step.
  • Ideal for hard to reach areas, such as under pavement or buildings.