Camp Lejeune Background U.S. Marine Corps Base Camp Lejeune was established near the city of Jacksonville, N.C, in 1942. In 1982, the Marine Corps discovered volatile organic compounds (VOCs) in several drinking water wells that fed into two of the eight water systems at the base. Leaking underground storage tanks, spills and drum disposal caused groundwater contamination. At the Tarawa Terrace area, groundwater contamination was also caused by solvent-disposal practices at ABC One-Hour Cleaners. The Agency for Toxic Substances and Disease Registry (ATSDR) conducts research regarding the groundwater contamination at Camp Lejeune. ATSDR is a federal public health agency of the U.S. Department of Health and Human Services whose mission is to serve the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and disease related to toxic substances. ATSDR website for Camp Lejeune study. Research List of Reports: Summary of the water
Read MoreDensity-driven advection of gas phase due to vaporization of chlorinated volatile organic compounds (VOCs) has a significant effect on fate and transport of contaminants. In this study, we investigated the effects of density-driven advection, infiltration, and permeability on contaminant plume evolution and natural attenuation of VOCs in the subsurface system. To analyze these effects, multiphase flow and contaminant transport processes were simulated using a three-dimensional Galerkin-finite-element-based model. Trichloroethylene (TCE) is selected as a target contaminant. Density-driven advection of gas phase elevated the potential of groundwater pollution in the saturated zone by accelerating downward migration of vaporized contaminant in the unsaturated zone. The advection contributed to increased removal rates of non-aqueous phase liquid (NAPL) TCE source and reduced dissolved TCE plume development in the downstream area. Infiltration reduced the velocity of the density-driven advection and its influence zone, but raised TCE transfer from the unsaturated to the saturated zone. The variation
Read MoreIn-situ air sparging (IAS) is used for the clean-up of soil and groundwater that are contaminated with volatile organic compounds in relatively permeable subsurface environments. In this study, we investigated the secondary groundwater and gas flow fields that develop in the vicinity of single and multiple air sparging wells. The purpose is to evaluate their effects on contaminant plume migration and thus, remediation. Governing equations describing multiphase flow and contaminant transport in a three-dimensional domain were formulated and solved using the Galerkin finite element technique. Trichloroethylene was selected as a target contaminant. The increase in air injection contributed to an increase in the size of the IAS cone of influence and the gas saturation levels within the cone. This reduced the groundwater velocity within the cone and increased the zone of detour of groundwater around the air sparging wells. This outcome was quantified and compared under several IAS operations. Different
Read More