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Characterization of aquifer relationships by using geochemical techniques for plume delineation

Description: Conventional approaches to characterize aquifers at hazardous waste sites rely heavily on the installation of monitoring wells, hydraulic testing, and sampling and analysis of groundwater for contaminant concentrations. The use of geochemical techniques to determine relationships among aquifers in environmental investigations is limited, in part, because of a generally held view that these techniques may not be useful for shallow aquifers. In this paper, the authors discuss the use of (a) major ion compositions, (b) stable isotope ratios of oxygen, hydrogen, and carbon, and (c) the abundance of tritium to identify multiple aquifers, to establish the lateral extent of aquitards, and to determine hydraulic interconnections among aquifers at two hazardous waste sites. Experience with these and ongoing investigations at several other sites demonstrates that carefully conducted geochemical sampling and analysis of limited samples of groundwater provide an effective tool for hydrogeologic characterization in a variety of geologic settings.
Date: April 1, 1994
Creator: Aggarwal, P. K.; Burton, J. C. & Rose, C. M.
Partner: UNT Libraries Government Documents Department

A technical approach to groundwater contamination problems

Description: Argonne National Laboratory has been performing technical investigations at sites in Nebraska and Kansas that have identified groundwater contamination by carbon tetrachloride. This comprehensive program will ultimately provide the affected communities with safe drinking water. The first step in the program is to evaluate the available data and identify sites that will require an Alternate Water Supply Study (AWSS). The objective of the AWSS is to identify options for providing a safe drinking water supply to all users, in compliance with the Safe Drinking Water Act. The AWSS consists of an engineering and cost evaluation followed by implementation of the selected alternative. For sites with contamination less than a specific concentration, the AWSS is regarded as a satisfactory long term solution, and no further action is taken. For those sites with concentrations above that specific limit, the AWSS implementation is regarded as only a stopgap measure, and the site is selected for additional remedial action. The first step of the remedial action is an Expedited Site Characterization (ESC). The ESC was developed at Argonne to decrease the cost and time of the remedial investigation and feasibility study while producing a high-quality technical investigation. The ESC is designed to characterize the contaminant plume configuration and movement, which requires an understanding of the geological and hydrogeologic controls on groundwater movement as well as the nature and extent of any remaining carbon tetrachloride source in the soils. The ESC program uses a multidisciplinary technical approach that incorporates geology, geochemistry, geohydrology, and geophysics. Field activities include sampling, chemical analysis, and borehole and surface geophysical surveys.
Date: June 1, 1993
Creator: Burton, J. C.; Leser, C. & Rose, C. M.
Partner: UNT Libraries Government Documents Department

Correct use of cone penetrometer sensors to predict subsurface conditions

Description: When cone penetrometer testing (CPT) technology is used with in-situ sensors and probes to characterize subsurface conditions in environmental investigations, each sensor must be calibrated with high quality, site specific data to establish essential interpretation criteria. Mechanical, geophysical, and chemical sensor data collected for a site in South Carolina without such controls were misleading. Core logs obtained subsequently had major lithologic discrepancies with the soil classification based on the CPT sensor data. In addition, detailed core sampling and laboratory analysis showed that the sensor data on chemical contaminants included false positive and false negative results. In contrast, for a site in Nebraska, CPT data calibrated with high quality site controls provided a detailed interpretation of subsurface conditions relevant to contaminant fate and transport. On the basis of the work in Nebraska, Argonne scientists are continuing to develop criteria to improve the interpretation of complex subsurface stratigraphy.
Date: September 1, 1997
Creator: Walker, J.L.; Rose, C.M.; Armstrong, S.C. & Burton, J.C.
Partner: UNT Libraries Government Documents Department

Collecting real-time soil moisture profiles in the vadose zone

Description: The savings realized by using cone penetrometer (CPT) technology to supplement site characterization work are well documented. Adding soil moisture profiling to CPT testing can further enhance the interpretation of geologic and hydrogeologic conditions at a site. The performance characteristics of three soil moisture probes (SMPs) used with direct push technology were tested at a site in South Carolina. In the unsaturated zone, all three probes predicted volumetric soil moisture within {+-}5 moisture units of the laboratory values more than 65% of the time. When the results were outside this range, the difference was not large enough to lead to erroneous interpretations of the actual soil moisture trends. Results of testing in a variety of hydrogeologic conditions indicate that when SMPs are used with proper site calibration and controls, each probe can predict soil moisture values within the unsaturated zone that closely match laboratory results, in real time.
Date: September 1997
Creator: Rose, C. M.; Armstrong, S. C.; Walker, J. L.; Young, G. N. & Burton, J. C.
Partner: UNT Libraries Government Documents Department

Expedited Site Characterization: A rapid, cost-effective process for preremedial site characterization

Description: Argonne National Laboratory has developed a unique, cost- and time-effective, technically innovative process for preremedial site characterization, referred to as Expedited Site Characterization (ESC). The cost of the ESC field sampling process ranges from 1/10 to 1/5 of the cost of traditional site characterization. The time required for this ESC field activity is approximately 1/30 of that for current methods. Argonne`s preremedial site investigations based on this approach have been accepted by the appropriate regulatory agencies. The ESC process is flexible and neither site nor contaminant dependent. The process has been successfully tested and applied in site investigations of multiple contaminated landfills in New Mexico (for the US Department of the Interior`s Bureau of Land Management [BLM]) and at former grain storage facilities in Nebraska and Kansas, contaminated with carbon tetrachloride (for the Department of Agriculture`s Commodity Credit Corporation [CCC/USDA]). A working demonstration of this process was sponsored by the US Department of Energy (DOE) Office of Technology Development as a model of the methodology needed to accelerate site characterizations at DOE facilities. This report describes the application of the process in New Mexico, Nebraska and Kansas.
Date: November 1, 1993
Creator: Burton, J. C.; Walker, J. L.; Jennings, T. V.; Aggarwal, P. K.; Hastings, B.; Meyer, W. T. et al.
Partner: UNT Libraries Government Documents Department