Evaluating the potential for quantitative monitoring of in situ chemical oxidation of aqueous‐phase TCE using in‐phase and quadrature electrical conductivity. Issue 7 (14th July 2015)

• Record Type: Journal Article
• Authors: Hort, R. D.; Revil, A.; Munakata‐Marr, J.; Mao, D.
• Is Part Of: Water resources research. Volume 51:Issue 7(2015:Jul.)
• Page Start: 5239
• Page End: 5259
• Publication Date: 2015-07-14
• Subjects: Hydrology -- Periodicals; 333.91
• DOI: 10.1002/2014WR016868
• Languages: English
• ISSNs: 0043-1397

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Electrical resistivity measurements can potentially be used to remotely monitor fate and transport of ionic oxidants such as permanganate ( <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgj2fhbxqh3" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00431397:media:wrcr21542:wrcr21542-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>MnO</mml:mtext></mml:mrow><mml:mn>4</mml:mn><mml:mo>−</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives></inline-formula>) during in situ chemical oxidation (ISCO) of contaminants like trichloroethene (TCE). Time‐lapse two‐dimensional bulk conductivity and induced polarization surveys conducted during a sand tank ISCO simulation demonstrated that <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgj2fhbxqgj" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00431397:media:wrcr21542:wrcr21542-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>MnO</mml:mtext></mml:mrow><mml:mn>4</mml:mn><mml:mo>−</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives></inline-formula> plume movement could be monitored in a qualitative manner using bulk conductivity tomograms, although chargeability was below sensitivity limits. We also examined changes to in‐phase and quadrature electrical conductivity resulting from ion injection, MnO<sub>2</sub> and Cl<sup>−</sup> production, and pH change during TCE and humate oxidation by <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgj2fhbxqf0" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00431397:media:wrcr21542:wrcr21542-math-0003" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>MnO</mml:mtext></mml:mrow><mml:mn>4</mml:mn><mml:mo>−</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives></inline-formula> in homogeneous aqueous solutions and saturated porous media samples. Data from the homogeneous samples demonstrated that inversion of the sand tank resistivity data using a common Tikhonov regularization approach was insufficient to recover an accurate conductivity distribution within the tank. While changes to in‐phase conductivity could be successfully modeled, quadrature conductivity values could not be directly related to TCE oxidation product or <inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgj2fhbxqdf" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:00431397:media:wrcr21542:wrcr21542-math-0004" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msubsup><mml:mrow><mml:mtext>MnO</mml:mtext></mml:mrow><mml:mn>4</mml:mn><mml:mo>−</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives></inline-formula> concentrations at frequencies consistent with field induced polarization surveys, limiting the utility of quadrature conductivity for monitoring ISCO.</p> </abstract>