title: Ferrographic tracking of bacterial transport in the field at the narrow channel focus area, Oyster, VA.
abstract: The first results from an innovative bacterial tracking technique, ferrographic capture, applied to bacterial transport in groundwater are reported in this paper. Ferrographic capture was used to analyze samples during an October 1999 bacterial injection experiment at the Narrow Channel focus area of the South Oyster site, VA. Data obtained using this method showed that the timing of bacterial breakthrough was controlled by physical (hydraulic conductivity) heterogeneity in the vertical dimension as opposed to variation in sedimentsurface or aqueous chemical properties. Ferrographic tracking yielded results that compared well with results from other tracking techniques over a concentration range of 8 orders of magnitude and provided a low detection limit relative to most other bacterial tracking techniques. The low quantitation limit of this method (approximately 20 cells/mL) allowed observation of transport of an adhesion-deficient bacterium over distances greater than 20 m in the fine sand aquifer underlying this site.
authors.affiliation: Department of Geology and Geophysics, University of Utah, Salt Lake City 84112, USA. wjohnson@mines.utah.edu
authors.forename: W P
authors.initials: WP
authors.lastname: Johnson
authors.forename: P
authors.initials: P
authors.lastname: Zhang
authors.forename: M E
authors.initials: ME
authors.lastname: Fuller
authors.forename: T D
authors.initials: TD
authors.lastname: Scheibe
authors.forename: B J
authors.initials: BJ
authors.lastname: Mailloux
authors.forename: T C
authors.initials: TC
authors.lastname: Onstott
authors.forename: M F
authors.initials: MF
authors.lastname: Deflaun
authors.forename: S S
authors.initials: SS
authors.lastname: Hubbard
authors.forename: J
authors.initials: J
authors.lastname: Radtke
authors.forename: W P
authors.initials: WP
authors.lastname: Kovacik
authors.forename: W
authors.initials: W
authors.lastname: Holben
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001431:Bacteriological Techniques; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial / Q000379:methods; D020585:Comamonas / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D005290:Ferric Compounds; D008280:Magnetics; D016133:Polymerase Chain Reaction; D014768:Virginia; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D005290:Ferric Compounds; D014874:Water Pollutants, Chemical; C001215:ferrite