Rapid Assessment of Remedial Effectiveness and Rebound in Fractured Bedrock
Technical Report,17 Jun 2013,17 Jun 2017
CDM Smith Edison United States
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Fractured rock sites, impacted with chlorinated solvents such as tetrachloroethene PCE ortrichloroethene TCE, remain a significant environmental challenge for the Department of Defense. Efforts to apply in situ remedial technologies, such as chemical oxidation or bio augmentation, have often proved challenging andor unsuccessful with respect to attaining remedial objectives in fractured rock aquifers. Contaminant rebound typically is observed due to processes such as dense non-aqueous phase liquid DNAPL dissolution, matrix back-diffusion, andor release of contaminants from low permeabilitybypassed fracture zones. Unfortunately, the ineffectiveness of these remedial technologies is typically not recognized until after substantial time and resources have been expended via in situ pilot testing, and the mechanisms controlling the observed contaminant rebound often remain unidentified. This lack of understanding in the conceptual site model hinders effective site management, particularly with respect to designing an appropriate remedial approach and identifying the practical limits of remediation.
- Organic Chemistry
- Hydrology, Limnology and Potamology