Push-pull test for in situ determination of microbial metabolic activities: denitrification and methanogenesis
Odenthal, Paul James.
MetadataShow full item record
Quantitative information on subsurface microbial processes is needed for many applications, but information obtained by existing methods can be difficult to interpret. The goal of this project was to develop a single well, 'push-pull' test for the determination of in situ microbial metabolic activities. The method consists of an injection of a test solution into an existing monitoring well followed by the extraction of the groundwater/test solution mixture from the same well. The test solution consists of a tracer and one or more reactive solutes selected to investigate the activity of a specific microbial system. During the extraction phase, the concentrations of all components of the test solution and potential reaction products are measured and used to develop breakthrough curves. A series of tests were used to investigate the processes of denitrification and methanogenesis by injecting solutions with nitrate, nitrite, or dissolved hydrogen gas in a petroleum contaminated, anaerobic zone of an unconfined, alluvial aquifer and in an uncontaminated, aerobic zone of the same aquifer located directly upgradient of the contaminated zone. Nitrate and nitrite injections yielded utilization rates that were approximately 2.5 times greater in the contaminated zone (than in the uncontaminated zone) where 80% of the injected nitrate mass and 90% of the injected nitrite mass were utilized. During the nitrate injection tests, trace amounts of produced nitrite were detected. The hydrogen injection test resulted in a 60% loss of hydrogen with no detectable methane production in the contaminated well. The push-pull field procedure developed in this project was shown to be capable of determining and quantifying microbial metabolic activity in situ.
CIVINS (Civilian Institutions) Thesis document
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Origin of the deep Bering Sea nitrate deficit : constraints from the nitrogen and oxygen isotopic composition of water column nitrate and benthic nitrate fluxes Lehmann, Moritz F.; Sigman, Daniel M.; McCorkle, Daniel C.; Brunelle, Brigitte G.; Hoffmann, Sharon S.; Kienast, Markus; Cane, Greg; Clement, Jaclyn (American Geophysical Union, 2005-10-12);On the basis of the normalization to phosphate, a significant amount of nitrate is missing from the deep Bering Sea (BS). Benthic denitrification has been suggested previously to be the dominant cause for the BS nitrate ...
Center on Contemporary Conflict (Monterey, California. Naval Postgraduate School, 2013);Given the possible hostile use of biological agents, the broader scientific community must be engaged in building microbial forensic capacity. The development of microbial forensics illustrates how global life science ...
Net primary productivity estimates and environmental variables in the Arctic Ocean: An assessment of coupled physical-biogeochemical models Lee, Younjoo J.; Matrai, Patricia A.; Friedrichs, Marjorie A.M.; Saba, Vincent S.; Aumount, Olivier; Babin, Marcel; Buitenhuis, Erik T.; Chevallier, Matthieu; de Mora, Lee; Dessert, Morgane; Dunne, John P.; Ellingsen, Ingrid H.; Feldman, Doron; Frouin, Robert; Gehlen, Marion; Gorguess, Thomas; Ilyina, Tatiana; Jin, Meibing; John, Jasmin G.; Lawrence, Jon; Manizza, Manfredi; Menkes, Christophe E.; Perruche, Coralie; Le Fouest, Vincent; Popova, Ekaterina E.; Romanou, Anastasia; Samuelsen, Annette; Schwinger, Jörg; Séférian, Roland; Stock, Charles A.; Tjiputra, Jerry; Tremblay, L. Bruno; Ueyoshi, Kyozo; Vichi, Marcello; Yool, Andrew; Zhang, Jinlun (AGU Publications, 2016-12);The relative skill of 21 regional and global biogeochemical models was assessed in terms of how well the models reproduced observed net primary productivity (NPP) and environmental variables such as nitrate concentration ...