BGS has been working with the Japan Atomic Energy Agency (JAEA) on sedimentary rock environments in northern Japan. We have been investigating changes in transport properties resulting from microbial activity in short experiments (39 days maximum) using the BGS developed Biological Flow Apparatus.
Experiments have shown for the first time that the denitrifying bacterium Pseudomonas denitrificans can survive and thrive when injected into flow-through column experiments containing fractured diatomaceous mudstone and synthetic groundwater under pressurised conditions (Figure 1).
The BioTran study investigates the significance of the impacts of microbial activity on the transport properties of rocks and subsequent movement of contaminants.
Our recent work has focused on geological environments, which are relevant to the disposal of radioactive waste.
Monitoring during column experiments in the Japan study revealed few significant changes in fluid chemistry but changes in the permeability of the biotic column were observed. These can be explained by biofilm formation. Such changes have the potential to inhibit the transport of radionuclides.
Additionally, the microbes etched and dissolved some of the minerals (Figure 2).
The methodologies used in these experiments could be adapted to obtain information from cores originating from a variety of geological environments including oil reservoirs, aquifers and toxic waste disposal sites. Such investigations provide an improved understanding of the impact of microbial activity on the transport of a range of solutes, such as groundwater contaminants and gases (e.g. injected carbon dioxide).
The methodologies can also be applied to investigate the role that microbes play in the mobilisation of potentially harmful elements in soil, particularly in the context of contaminated land.
Harrison, H, West, J M, Milodowski, A E, Bateman, K, Coombs, P, Harrington, J, Holyoake, S, Lacinska, A, Turner, G and Wagner, D. 2010. Microbial influences on fracture surfaces of intact Horonobe mudstone. BioTran Progress Report Sept 2009 – January 2010. British Geological Survey Report OR/10/067. Available from http://nora.nerc.ac.uk/13590/.
Coombs, P, West, J M, Wagner, D, Turner, G, Noy, D J, Milodowski, A E, Lacinska, A, Harrison, H and Bateman, K. 2008. Influence of biofilms on transport of fluids in subsurface granitic environments — some mineralogical and petrographical observations of materials from column experiments. Mineralogical Magazine 72(1) 393—397. Available from http://nora.nerc.ac.uk/3854/.
Hama, K, Bateman, K, Coombs, P Hards, V L, Milodowski, A E, West, J M, Wetton, P D, Yoshida, H and Aoki, K. 2001. Influence of bacteria on rock-water interaction and clay mineral formation in subsurface granitic environments. Clay Minerals 36, 599—613. (Abstract).
Tuck, V A, Edyvean, R G J, West, J M, Bateman, K, Coombs, P, Milodowski, A E and McKervey, J A. 2006. Biologically induced clay formation in subsurface granitic environments. Journal of Geochemical Exploration 90, 123—133. DOI: 10.1016/j.gexplo.2005.09.007.
Coombs, P, Wagner, D, Bateman, K, Harrison, H, Milodowski, A E, Noy, D and West, J M. 2010. The role of biofilms in subsurface transport processes. Quarterly Journal of Engineering Geology and Hydrogeology 43, 131—139. Available from http://nora.nerc.ac.uk/9932/.
West, J M, McKinley, I G and Stroes-Gascoyne, S. 2009. Implications of microbial redox catalysis in analogue systems for repository safety cases. Proceedings 12th International Conference on Environmental Remediation and Radioactive Waste ICEM 2009. ASME. (Available on CD-ROM). ICEM2009-16336. ISBN 978-0-7918-3865-X.
Humphreys, P N, West, J M and Metcalfe, R. 2009. Microbial effects on repository performance. Technical Report QRS-1378Q-1. Livelink reference number: 12208035. UK Nuclear Decommissioning Agency. Available from NDA bibliography http://www.nda.gov.uk/documents/biblio/).
West, J M, McKinley, I G, Neall, F B, Rochelle, C A and Bateman, K. 2006. Microbiological effects on the cavern extended storage (CES) repository for radioactive waste. Journal of Geochemical Exploration 90 (1—2) pp 114—122. Available from http://nora.nerc.ac.uk/231/.
West, J M and McKinley, I G. 2002. The geomicrobiology of radioactive waste disposal. In: The Encyclopaedia of Environmental Microbiology Biutton, G (editor). (John Wiley, New York, 2661—2674.) ISBN: 978-0-471-35450-5. Available through http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0471354503,descCd-description.html).
West, J M, McKinley, I G and Stroes-Gascoyne, S. 2002. Microbial effects on waste repository materials. In: Microbiology and Radioactivity Keith-Loach, M and Livens, F (editors). (Elsevier.) pp 255—278 ISBN 978-0080437088 DOI: 10.1016/S1569-4860(02)80038-9.
West, J M, McKinley, I G, Palumbo-Roe, B and Rochelle, C A. Potential impact of CO2 storage on subsurface microbial ecosystems and implication for groundwater quality. Energy Procedia (in press).
Jones, D G, Lister, T R, Smith, D J, West, J M Coombs, P, Gadalia, A, Brach. M, Annunziatellis, A and Lombardi, S. In Salah Gas CO2 Storage JIP: Surface gas and biological monitoring. Energy Procedia (in press).
West J M, Pearce, J M, Coombs, P, Ford, J R, Scheib, C, Colls, J J, Smith, K L and Steven, M. 2009. The impact of controlled injection of CO2 on the soil ecosystem and chemistry of an English lowland pasture. Energy Procedia 1, pp 1863—1870. Available from http://nora.nerc.ac.uk/9821/.
Krüger, M, West, J M, Oppermann, B, Dictor, M-C, Frerichs, J, Joulian, C, Jones, D, Coombs, P, Green, K, Pearce, J, May, F and Möller, I. 2009. Ecosystem effects of elevated CO2 concentrations on microbial populations at a terrestrial CO2 vent at Laacher See, Germany. Energy Procedia 1, pp 1933—1939. DOI:10.1016/j.egypro.2009.01.252.
Maul, P, Beaubien, S, Bond, A, Limer, L, Lombardi, S, Pearce, J, Thorne, M and West, J M. 2009. Modelling the fate of carbon dioxide in the near-surface environment at the Latera natural analogue site. Energy Procedia 1, pp 1879—1885. DOI: 10.1016/j.egypro.2009.01.245
Beaubien, S E, Ciotoli, G, Coombs, P, Dictor, M C, Krüger, M, Lombardi, S, Pearce, J M and West J M. 2008. The impact of a naturally occurring CO2 vent on the shallow ecosystem and soil chemistry of a Mediterranean pasture (Latera, Italy). International Journal of Greenhouse Gas Control 2 pp 373—387. Available from http://nora.nerc.ac.uk/4777/.
Contact Dr Dr Simon Gregory for further information