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Enhanced Degradation of Dissolved Benzene and Toluene Using a Solid Oxygen-Releasing Compound |
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| Authors: | Gino C Bianchi-Mosquera Richelle M Allen-King Douglas M Mackay |
| Institution: | Gino Bianchi-Mosquera is principal geochemist at Stollar Bianchi (140 Ravenna Dr., Long Beach, CA 90803). He received a B.A. degree in geochemistry from Occidental College in Los Angeles, California, an M.S. degree in geochemistry from The Pennsylvania State University, and a D. Env. degree from the University of California, Los Angeles, in 1982, 1986, and 1993, respectively. His research interests include the transport and fate of organic compounds in the subsurface, and the design and evaluation of new aquifer cleanup techniques.;Richelle M. Allen-King is an assistant professor in the Geology Department at Washington State University (Pullman, WA 99164). She received a B.A. in chemistry from the University of California, San Diego, in 1983, a Ph.D. in earth sciences from the University of Waterloo in 1991, and recently completed a post-doc in the Waterloo Centre for Groundwater Research. Her dissertation research concerned the fate and transport of dissolved BTEX during infiltration in sandy soil. Her research focuses on processes which affect the transport of organic chemicals in the subsurface.;Douglas Mackay is adjunct professor in the Centre for Groundwater Research at the University of Waterloo (Waterloo, Ontario N2L 3G1), Canada, and a visiting scientist at the UCLA Department of Civil Engineering. From 1986 to mid- 1990 he was a faculty member in the environmental science and engineering program of the UCLA School of Public Health. His research focuses on field studies of transport and fate of organic chemicals in ground water and ground water decontamination technologies. Mackay received a B.S. in engineering and M.S. and Ph.D. degrees in civil engineering from Stanford University in 1970, 1973, and 1981, respectively. |
| Abstract: | A field lest to evaluate the applicability of an oxygon-releasing compound (ORC) to the rernediation of ground water contaminated with benzone and toluene was conducted in the Borden Aquifer in Ontario. Canada. Benzene and toluene were injected as organic substrates to represent BTEX compounds, bromide was used as a tracer, and nitrate was added to avoid nitrate-limited conditions. The fate of the solutes was monitored along four lines of monitoring points and wells. Two lines studied the behavior of the solutes upgradient and downgradient of two large-diameter well screens filled with briquets containing ORC and briquets without ORC. One line was used to study the solute behavior upgradient and downgradient of columns of ORC powder placed directly in the saturated zone. The remaining line was a control. The results indicate that ORC in both briquet and powder form can release significant amounts of oxygen to conlaminated ground water passing by it. In the formulation used in this work, oxygen release persisted for at least 10 weeks. Furthemiore, the study indicates that the enhancement of the available dissolved oxygen content of at least 4 mg/L each of the ground water by ORC can support biodegradation of benzene and toluene dissolved in ground water. Such concentrations are typical of those encountered at sites contaminated with petroleum hydrocarbons; therefore, these results suggest that there is promise for ORC to enhance in situ biodegradation of BTKX contaminants at such sites using passive (nonpumping) systems to contact the contaminated ground water with the oxygen source. |
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