USGS scientists conducting chemical analyses on site and in an onsite mobile laboratory at the Norman Landfill, Oklahoma. In order to predict how long landfill leachate will continue to contaminate groundwater after a landfill is closed, it is critical to understand how effective natural processes are in removing those contaminants over time.
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USGS scientist processing samples in an onsite mobile laboratory at the Norman Landfill, Oklahoma. The scientist is using a chamber without oxygen inside (anaerobic conditions) to isolate reactive samples from the atmosphere. Scientists are studying how natural processes mitigate contamination from landfill leachate.
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USGS scientist collecting water-quality samples during a hydrogen-consuming, push-pull injection test at the Normal Municipal Landfill Research Site, Oklahoma. The test is used to determine what microbiological processes are active in the subsurface at groundwater contamination sites.
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A view of the berm of the Normal Municipal Landfill, Oklahoma, and the area that overlies the leachate plume.
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Map of the study area showing well transect location and groundwater flow direction.
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Collecting pore waters from a core to determine natural attenuation rates.
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USGS scientist using a syringe to withdraw water for analysis of geochemical parameters.
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Passive-diffusion samplers ("peepers") are driven into a wetland to observe the geochemistry of the leachate plume's discharge area.
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USGS scientists analyzing water samples in the field.
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Gas samples are collected from an unsaturated zone well to study the natural biodegradation of contaminants.
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A dual-frequency GPS receiver was used to survey the location of passive-diffusion samplers ("peepers") in a wetland at the leading edge of the leachate plume.
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Installation of a well in the unsaturated zone above the leachate plume.
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