Date of Award
Master of Science
Geological and Environmental Sciences
Dr. Alan E. Kehew
Dr. Duane R. Hampton
Dr. R. V. Krishnamurthy
Masters Thesis-Open Access
Volatile organic compounds (VOCs) are detected in two groundwater monitoring wells (MW-60 and MW-62S) located along the northern, downgradient property line of the McGill Road Landfill (MRL) in Jackson, Michigan. Potential on-site sources for groundwater impact are two distinct landfill units at the MRL. Leachate chemistry suggested that landfill leachate was not the source of VOCs detected in groundwater. A potential source for VOCs was landfill gas. Sources of landfill gas in the vicinity of the impacted wells included the distinct MRL landfill units as well as the old Jackson County Landfill (JCL), located hydraulically downgradient from the impacted wells. Upon determining that groundwater impacts were likely caused by subsurface migration of landfill gas, an investigation was performed to verify that landfill gas was the source of VOCs and to determine if it was feasible to identify the source of the landfill gas based on its isotopic signature.
The results of the investigations show that there is little evidence to indicate that the detected VOCs are the result of leachate migration from the upgradient MRL site. Further, the investigations have shown that there are significant quantities of landfill gas present in the subsurface in the study area; thus, gas to groundwater partitioning of VOCs was a viable source for the VOCs detected in the impacted wells.
Isotopic analysis of gas samples indicates that gas originating in the JCL refuse is more characteristic of the subsurface gas present in the vadose zone around the impacted wells along the north boundary of MRL than are samples of MRL landfill gas. VOC concentrations in gas samples collected from potential MRL landfill units are too low to account for the VOC concentrations observed in the vadose zone. Off-site concentrations of the VOC are higher than the concentrations measured in MRL landfill gas samples. Conversely, VOCs detected in landfill gas samples from the JCL were comparable to those observed in the vadose zone.
Wallis, "Application of Geochemical Fingerprinting and Isotopes to Identity Landfill Gas Impacts to Groundwater" (2003). Master's Theses. 4763.