HR: 1330h
AN: H12A-0966    [PDF]
TI: ENHANCED REMEDIATION OF TOLUENE IN THE VADOSE ZONE VIA A NITRATE-RICH NUTRIENT SOLUTION: FIELD STUDY
AU: Tindall, J A
EM: jtindall@usgs.gov
AF: U.S. Geological Survey, MS 413, Box 25046 Federal Center, Denver, CO 80225-0046 United States
AU: * Friedel, M J
EM: mfriedel@usgs.gov
AF: U.S. Geological Survey, MS 413, Box 25046 Federal Center, Denver, CO 80225-0046 United States
AB: The objective of this study was to test the effectiveness of nitrate-rich nutrient solutions and hydrogen peroxide (H202) to enhance in-situ microbial remediation of toluene. Three sand filled plots (2 m2 surface area and 1.5 meters deep) were tested in three phases (each phase lasting approximately 2 weeks). During each phase, toluene (21.6 mol as an emulsion in 50L of water) was applied uniformly via sprinkler irrigation. Passive remediation was allowed to occur during the first (control) phase. A nutrient solution (modified Hoagland), concentrated in 40L of water, was tested during the second phase. The final phase involved addition of 230 moles of H202 in 50L of water to increase the available oxygen needed for aerobic biodegradation. During the first phase, toluene concentrations in soil gas were reduced from 120 ppm to 25 ppm in 14 days. After the addition of nutrients during the second phase, concentrations were reduced from 90 ppm to about 8 ppm within 14 days, and for the third phase (H202), toluene concentrations were about 1 ppm after only five days. Initial results suggest that this method could be an effective means of remediating a contaminated site, directly after a BTEX spill, without the intrusiveness and high cost of other abatement technologies such as bioventing and soil vapor extraction. However, further tests need to be completed to determine the effect of each of the BTEX components.
UR: http://www.agu.org
DE: 1866 Soil moisture
DE: 1875 Unsaturated zone
DE: 3210 Modeling
DE: 3260 Inverse theory
DE: 5139 Transport properties
SC: Hydrology [H]
MN: 2003 Fall Meeting