USGS scientist holding a sample vile up to a color scale to determine the concentration of dissolved oxygen in groundwater. At contamination sites where subsurface cleanup operations are taking place, oxygen may play a more important role in the biodegradation of contaminants than previously thought. Photo credit: USGS.
USGS scientist examining an outcrop of organic-rich sediment that drives sustainable natural attenuation of a chlorinated-solvents plume in the ground-water system underlying Kings Bay, Georgia.
Diffusion samplers were placed in the bed sediments of the Kenai River, Alaska, to monitor the biogeochemistry of a chloroethene plume as it discharges into the river.
USGS scientists studied the natural attenuation of a chlorinated-solvents plume at an old dry-cleaning facility near Soldonta, Alaska. Here groundwater is being sampled to assess redox conditions in the plume.
USGS scientists assisted the U.S. Navy with the design and assessment of an innovative remediation system that involved the injection of an oxygen-release compound in the source area of a chlorobenzene and benzene plume at the Naval Air Station, Pensacola, Florida. The two transects are along groundwater flow paths.
USGS scientists installing diffusion samplers and microcosms to study subsurface bacteria that degrade trichloroethylene at the Naval Air Warfare Center Research Site, West Trenton, New Jersey (circa 2005). The samplers will help USGS and U.S. Navy scientists evaluate the performance of a biostimulation and bioaugmentation experiment.
USGS scientists strapped syringes to the sides of the packer pipe rod to monitor dissolved hydrogen gas concentrations, which indicate predominant biodegradation processes. The packer system isolates six separate zones immediately downgradient from the trichloroethylene (TCE) plume area where bacteria will be injected by the U.S. Navy's consultant in a biostimulation and bioaugmentation program.
Drilling operations at the Naval Air Warfare Center Research Site, West Trenton, New Jersey in the center of a trichloroethylene (TCE) plume (circa 2005). A multi-level monitoring system was installed to evaluate the impact of a biostimulation and bioaugmentation remediation program on the quality of water in the fractured bedrock.
Samples of fractured rock were collected with a 4-inch coring bit and were analyzed for concentrations of volatile organic compounds (VOCs), providing a direct measure of the contaminant concentrations in the rock matrix at the Naval Air Warfare Center Research Site, West Trenton, New Jersey.
USGS drilling operations (2004) at the Naval Air Warfare Center Research Site, West Trenton, New Jersey. The objective of the drilling program was to collect geologic and hydrogeologic information on a fault that controls the migration of a trichloroethylene (TCE) plume at the site.
Trichloroethylene (TCE) pipes at the Naval Air Warfare Center (NAWC) Research Site, West Trenton, New Jersey. Jet engine testing equipment was cooled with trichloroethylene (TCE). Leaking pipes created a plume of TCE in fractured sedimentary rock at the site.
A technician is pumping water from a multi-level well during an investigation of the natural attenuation of a chlorinated solvent plume under a fire training pit at the former Wurtsmith Air Force Base, Oscoda, Michigan. Tubing from the well leads to an in-line multi-parameter probe that records pH, dissolved oxygen, Eh, and temperature. Photo credit: Sheridan K Haack, USGS.
A technician is collecting water-quality samples from a multi-level well at the former Wurtsmith Air Force Base, Oscoda, Michigan. The samples were analyzed for chemical constituents that are indicators of natural attenuation processes.
DNA was extracted from aquifer solids from former Wurtsmith Air Force Base, Oscoda, Michigan, and was analyzed for patterns of microbial diversity in a plume of chlorinated solvents undergoing natural microbial biodegradation.
U.S. Environmental Protection Agency scientists collected aquifer-material samples using an anaerobic chamber as part of a study of the natural attenuation of trichloroethylene (TCE) at Picatinny Arsenal, New Jersey.
USGS scientists conducted a column study to determined desorption rates of trichloroethylene (TCE) from contaminated sediments from the Picatinny Arsenal, New Jersey, Site. Desorption was an important continuing source of TCE to the plume.
USGS scientists are about to sample a fresh sediment core for analysis of trichloroethylene (TCE) content to help estimate the mass of TCE sorbed on sediment in a subsurface-contaminant plume at the Picatinny Arsenal, New Jersey, Site.