A unifying theme of USGS Toxic Substances Hydrology Program investigations is
the characterization of the natural response of hydrologic systems to contamination. This makes the sites where
the investigations are conducted ideally suited to assessing potential long-term impacts, evaluating the
potential and the limitations of remediation by monitored natural
attenuation, and designing systems to monitor the performance of remediation where monitored natural
attenuation is being relied upon. The information presented on this page cuts across lines drawn by individual
investigations and projects so that information on the natural attenuation of contaminants can be presented in
one place.
Investigations and Research Activities
- Investigations
- Natural Attenuation Remediation-Related Activities
USGS scientists installing diffusion samplers
and microcosms to study subsurface bacteria that degrade trichloroethylene
at the Naval Air Warfare Center
Research Site, West Trenton, NJ (circa 2005). The samplers will
help USGS and U.S. Navy scientists evaluate the performance of a
biostimulation and bioaugmentation experiment.
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Fact Sheets
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 ground-water flow paths
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Collecting ground-water samples anaerobically in a glove bag as part of a study of the
biogeochemistry of a landfill leachate plume at the Norman Landfill Research
Site, OK. The glove bag helps preserve sensitive redox species so an accurate determination of the processes
that control the natural attenuation of the leachate can be made
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Collecting pore water from cores to identify natural attenuation processes in ground water
at the Bemidji Crude Oil Spill Site, MN. The scientists are withdrawing
water with a syringe from a core encased in polycarbonate tubing. The bottom of the core was
frozen to prevent fluid from escaping the core. This technique allows
for closely spaced samples that enable scientists to study the biogeochemical heterogeneity of contaminant
plumes
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Headlines
Bibliography
New Publications
Upcoming Publications
- Microbial degradation of chloroethenes in the fractured rock aquifer at NAWC Trenton under unamended and enhanced conditions: Bradley, P.M., U.S. Geological Survey Scientific Investigations Report (IN PRESS).
- Volatile fuel hydrocarbons and oxygenates in the environment (Section 9.12): Cozzarelli, I.M., and Baehr, A.L., in Heinrich, D.H., and Karl, K.T., eds., Environmental Geochemistry, Lollar, B.S., ed., in Treatise on Geochemistry, New York, Elsevier Science, v. 9 (IN PRESS).
Newly Published
- Threshold amounts of organic carbon needed to initiate reductive dechlorination in groundwater systems: Chapelle, F.H., Thomas, L.K., Bradley, P.M., Rectanus, H.V., and Widdowson, M.A., 2012, Remediation Journal, v. 22, no. 3, p. 19-28, doi:10.1002/rem.21318.
- Perils of categorical thinking: "Oxic/anoxic" conceptual model in environmental remediation: Bradley, P.M., 2012, Remediation Journal, v. 22, no. 3, p. 9-18, doi:10.1002/rem.21317.
- Dissolved oxygen as an indicator of bioavailable dissolved organic carbon in groundwater: Chapelle, F.H., Bradley, P.M., McMahon, P.B., Kaiser, K., and Benner, R., 2012, Ground Water, v. 50, no. 2, p. 230-241, doi:10.1111/j.1745-6584.2011.00835.x.
- Arsenic and life--Bacterial redox reactions associated with arsenic oxyanions: Oremland, R.S., 2012 in Drelich, R., ed., Water in Mineral Processing, Englewood, Colo., Society for Mining, Metallurgy, and Exploration, p. 17-27, ISBN:9780873353496.
USGS scientist collecting an unsaturated-zone gas sample with a syringe from a vapor
sampling well at the Bemidji Crude Oil Spill Research Site, Bemidji, MN.
The sample was used to study the natural attenuation of hydrocarbon vapors in the unsaturated zone.
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