title: Field examination of ground water quality as an indicator of microbiological activity at gasoline contaminated sites.
abstract: Various portable electrodes and an on-line colorimetric test kit were used in the field to examine ground water quality as an indicator of natural bioremediation across two sites in Connecticut having subsurface gasoline contamination. The parameters examined included dissolved oxygen, dissolved carbon dioxide, direct redox potential (Eh), nitrate, ammonia and pH. These parameters permitted delineating regions of aerobic and anaerobic microbiological activity. Variations in these parameters over an eighteen month period along with gas chromatographic analyses of certain gasoline components in the ground water indicated that in-situ bioremediation was effective at containing the petroleum contamination at both sites. It was found that a new on-line colorimetric test kit for the determination of oxygen was more accurate than a commonly used dissolved oxygen electrode.
authors.affiliation: Department of Chemistry, University of Connecticut, Storrs 06269-4060 USA.
authors.forename: R G
authors.initials: RG
authors.lastname: Norkus
authors.forename: J
authors.initials: J
authors.lastname: Maurer
authors.forename: N A
authors.initials: NA
authors.lastname: Schultz
authors.forename: J D
authors.initials: JD
authors.lastname: Stuart
authors.forename: G A
authors.initials: GA
authors.lastname: Robbins
authors.forename: R D
authors.initials: RD
authors.lastname: Bristol
mesh_terms: D000641:Ammonia / Q000737:chemistry; D001673:Biodegradation, Environmental; D002245:Carbon Dioxide / Q000032:analysis; D003124:Colorimetry; D005618:Fresh Water / Q000737:chemistry; D005742:Gasoline; D006863:Hydrogen-Ion Concentration; D017736:Ion-Selective Electrodes / Q000592:standards; D009566:Nitrates / Q000737:chemistry; D009862:Online Systems; D010084:Oxidation-Reduction; D010100:Oxygen / Q000032:analysis; D011786:Quality Control; D015203:Reproducibility of Results; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000592:standards
chemical_list: D005742:Gasoline; D009566:Nitrates; D014874:Water Pollutants, Chemical; D002245:Carbon Dioxide; D000641:Ammonia; D010100:Oxygen