Geophysical monitoring of coupled microbial and geochemical processes during stimulated subsurface bioremediation

Kenneth H. Williams, Andreas Kemna, Michael J. Wilkins, Jennifer Druhan, Evan Arntzen, A. Lucie N'Guessan, Philip E. Long, Susan S. Hubbard, Jillian F. Banfield

Research output: Contribution to journalArticlepeer-review


Understanding how microorganisms alter their physical and chemical environment during bioremediation is hindered by our inability to resolve subsurface microbial activity with high spatial resolution. Here we demonstrate the use of a minimally invasive geophysical technique to monitor stimulated microbial activity during acetate amendment in an aquifer near Rifle, Colorado. During electrical induced polarization (IP) measurements, spatiotemporal variations in the phase response between imposed electric current and the resultant electric field correlated with changes in groundwater geochemistry accompanying stimulated iron and sulfate reduction and sulfide mineral precipitation. The magnitude of the phase response varied with measurement frequency (0.125 and 1 Hz) and was dependent upon the dominant metabolic process. The spectral effect was corroborated using a biostimulated column experiment containing Rifle sediments and groundwater. Fluids and sediments recovered from regions exhibiting an anomalous phase response were enriched in Fe(II), dissolved sulfide, and cell-associated FeS nanoparticles. The accumulation of mineral precipitates and electroactive ions altered the ability of pore fluids to conduct electrical charge, accounting for the anomalous IP response and revealing the usefulness of multifrequency IP measurements for monitoring mineralogical and geochemical changes accompanying stimulated subsurface bioremediation.

Original languageEnglish (US)
Pages (from-to)6717-6723
Number of pages7
JournalEnvironmental Science and Technology
Issue number17
StatePublished - Sep 1 2009
Externally publishedYes

ASJC Scopus subject areas

  • General Chemistry
  • Environmental Chemistry


Dive into the research topics of 'Geophysical monitoring of coupled microbial and geochemical processes during stimulated subsurface bioremediation'. Together they form a unique fingerprint.

Cite this