Reactive Transport Model for Drilling Fluid Contamination, South McMurdo Sound, Antarctica
Tuesday, May 6, 2014
Ellen Raimondi
,
Geology and Environmental Geosciences, Northern Illinois University, Dekalb, IL
Andrea Greer
,
Geology and Environmental Geosciences, Northern Illinois University, Dekalb, IL
Melissa Lenczewski, Ph.D.
,
Northern Illinois University, DeKalb, IL
Justin Dodd, Ph.D.
,
Northern Illinois University, Dekalb, IL
This study explored the potential fate and transport of seawater-based drilling fluid used in the Antarctic Drilling Program South McMurdo Sound project (SMS). The SMS drilling reported a loss of 5.6 × 103 liters of drilling fluid to the surrounding formation throughout a borehole depth of 1142 m. The objective of this study is to create reactive transport scenarios to model the extent of fluid migration into the borehole formation. To achieve this, the model included the effects of long term biodegradation on the fluid, changes in microbiological activity and geochemical parameters over time, and created a reactive model from the data to simulate fluid flow. The biodegradation experiment was designed as a microcosm set up and divided into aerobic and anaerobic samples which were incubated at different temperatures. For six months samples were collected for δ13C isotope fractionation, pH, dissolved oxygen, conductivity and major cations and anions. Supporting biological data observed the changes in microbial populations using Biolog EcoPlates and polymerase chain reaction methods. The model used the RT3D program in USGS Groundwater Vistas package of MODFLOW. The model accounted for biodegradation kinetics and chemical processes, advection, and dispersion. This study compared the reactive model to a density model to illustrate the variation of the drilling fluid transport. The preliminary results indicated that drilling fluid will migrate from a few centimeters to meters within the pristine environments based on different scenarios.
Ellen Raimondi, Geology and Environmental Geosciences, Northern Illinois University, Dekalb, IL
Ellen Raimondi is working on her master’s degree at Northern Illinois University. Her thesis focuses on the potential fate and transport of seawater-based drilling fluids. Her interests are in biodegradation and bioremediation of groundwater contamination. Raimondi’s work at NIU has provided opportunity to learn more about how geochemistry, geomicrobiology, and hydrogeology all play a role in understanding our natural water sources.
Andrea Greer, Geology and Environmental Geosciences, Northern Illinois University, Dekalb, IL
Andrea Greer is a Graduate Student at Northern Illinois University.
Melissa Lenczewski, Ph.D., Northern Illinois University, DeKalb, IL
Melissa Lenczewski is an Associate Professor of Geomicrobiology and Organic Geochemistry in the Department of Geology and Environmental Geosciences and the Department of Biological Sciences at Northern Illinois University. She has substantial expertise with methods such as molecular techniques and PFLA techniques for detection of microorganisms in soil and water. She also has expertise in detection of simple organic compounds in water. Lenczewski conducted research on groundwater in the Yucatan Peninsula.
Justin Dodd, Ph.D., Northern Illinois University, Dekalb, IL
Dr. Justin Dodd is an assistant professor in the department of Geology and Environmental Geosciences at Northern Illinois University. His research focuses on stable isotope geochemistry applications in a range of geological and environmental settings including paleoclimate reconstruction, paleoecology, archeology, hydrology, biology, and isotope forensics.
