Environmental Health - Toxic Substances
U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting Charleston South Carolina March 8-12, 1999--Volume 3 of 3--Subsurface Contamination From Point Sources, Water-Resources Investigations Report 99-4018C
Evaluation of RNA Hybridization to Assess Bacterial Population Dynamics at Natural Attenuation Sites
By Lisa A. Reynolds and Sheridan K. Haack
To improve site characterization and monitoring of natural attenuation sites, a better understanding of bacterial population dynamics is necessary. Bacterial populations found in contaminated aquifers can be quantified and identified using RNA (ribonucleic acid) hybridization. This technique allows for identification of specific bacterial populations that are active in situ. In addition, some biodegradation processes can be inferred using this method. RNA hybridization was used to analyze methane-producing bacterial populations at a natural attenuation site contaminated with jet fuel and chlorinated solvents. Preliminary results indicate spatial and temporal changes in methane-producing bacterial populations. Further work will characterize different groups of methanogens. These different groups of methane-producing bacteria will be used to predict the biodegradation processes that are likely to be occurring on specific dates and locations. Knowledge of the dynamics of these bacterial populations and processes will aid in modeling and evaluation of contaminated sites at which monitored natural attenuation has been chosen as a remediation strategy.