Type of Document	Master's Thesis
Author	Das, Swati Jr.
Author's Email Address	PKSWATI@aol.com
URN	etd-12498-13011
Title	BIOREMEDIATION OF PCB CONTAMINATED SURFACE SOIL-A MICROCOSM STUDY
Degree	Master of Science
Department	Crop and Soil Environmental Sciences
Advisory Committee	Advisor Name Title Dr. Duane F. Berry Committee Chair Dr. Lucian W. Zelazny Committee Member Dr. Nancy G. Love Committee Member
Keywords	PCBs bioremediation contaminated surface soil methanogenic consortium.
Date of Defense	1997-02-12
Availability	restricted
Abstract BIOREMEDIATION OF PCB CONTAMINATED SURFACE SOIL - A MICROCOSM STUDY (ABSTRACT) This feasibility study was performed at Virginia Polytechnic Institute and State University (Blacksburg, VA) in collaboration with BioSystems Technology, Inc. (Blacksburg, VA). In this study, degradability of PCBs (Aroclor 1242) from an aged surface soil was evaluated using serum bottle microcosms containing aceticlastic methanogenic consortium, enriched from a municipal anaerobic digester. Two different experiments, "intermediate feed" and "starve and feed" were conducted by manipulating the methanogenic consortium with different amounts of acetate feeding, during 30 days of incubation. Disappearance of Aroclor 1242 in the microcosms was quantified using gas chromatography (GC). Significant differences in Aroclor 1242 removal between inoculated and uninoculated (control) microcosms were observed suggesting that the methanogenic consortium was responsible for Aroclor 1242 disappearance. However, GC-mass spectrometry (GC-MS) results could not confirm that disappearance of Aroclor 1242 was due to anaerobic dehalogenation. From another experiment, it was confirmed that removal of Aroclor 1242 was not due to evaporation losses during sample extraction. Toxicity of an aged Aroclor 1242 contaminated surface soil was evaluated on an aceticlastic methanogenic consortium, enriched from a municipal anaerobic digester. Microcosms were set up using different amounts of soil and inoculum. Total gas production in the microcosms was monitored during 30 days of incubation, using a glass syringe. Total methane production in the microcosms was quantitated using GC. Toxicity of the soil on the methanogenic inoculum was determined based on the decreased rate of methane production in the microcosms relative to non- soil containing controls. Compared to the control, there was reduction in total methane production in soil containing microcosms. Between 3-27% reduction in total methane production was noticed in microcosms containing different amounts of soil and consortium. Reduction in methane production seemed to increase with increasing amount of soil. Whether this decrease in methane production was due to toxicity of Aroclor 1242 on the methanogenic consortium or due possibly to the toxicity of trapped oxygen in the soil could not be determined. The rate of gas production in the soil microcosm was linear.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access  cpt1.pdf 8.58 Kb 00:00:02 00:00:01 00:00:01 < 00:00:01 < 00:00:01 cpt2.pdf 67.71 Kb 00:00:18 00:00:09 00:00:08 00:00:04 < 00:00:01 cpt3.pdf 17.07 Kb 00:00:04 00:00:02 00:00:02 00:00:01 < 00:00:01 cpt4.pdf 45.82 Kb 00:00:12 00:00:06 00:00:05 00:00:02 < 00:00:01 cpt5.pdf 94.97 Kb 00:00:26 00:00:13 00:00:11 00:00:05 < 00:00:01 cpt6.pdf 6.70 Kb 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 < 00:00:01 Swatietd.PDF 19.25 Kb 00:00:05 00:00:02 00:00:02 00:00:01 < 00:00:01 indicates that a file or directory is accessible from the Virginia Tech campus network only.

If you have questions or technical problems, please Contact DLA.