Baywood Publishing Company
0047-2433
1541-3802
Journal of Environmental Systems
BWES
300323
http://baywood.metapress.com/link.asp?target=journal&id=300323
31
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000031000120070701
Number 1 / 2004-2005
P32MX6518318
http://baywood.metapress.com/link.asp?target=issue&id=P32MX6518318
10.2190/2406-3212-6V40-3820
240632126V403820
2
A Risk Based, Multi-Component Model to Identify Contaminant Loadings and Transport through Groundwater Systems Under Uncertainty
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48
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20070614
20070614
240632126V403820.pdf
http://baywood.metapress.com/link.asp?target=contribution&id=240632126V403820
1
Todd
A.
Wang
William
F.
McTernan
U.S. Army, Ft. Bragg, North Carolina
Oklahoma State University, Stillwater
We developed and applied a suite of risk-based methods for characterizing the contaminant potentials from a former munitions plant in East Texas. The site was originally "clean closed" when a subsequent groundwater monitoring program disclosed areas of contamination by the chlorinated solvent, trichloroethylene (TCE) and others. As part of an overall decision model developed for the site, a series of probability-based mathematical and statistical models were developed to address off-site contamination and plume configuration. As with most historic hazardous waste sites, there was virtually no information relative to contaminant loading rates to the water table aquifer. These loads were reconstructed by comparing the results generated from a Monte Carlo-based technique which linked the vadose and saturated zone models to minimal groundwater data previously collected. The contaminant flux in the aquifer was assumed to coincide with activities at the munitions plants peaking as the plant was decommissioned and tailing off through subsequent years. This curve followed the classic boundary condition where the contaminant source is terminated after a period of flux into the aquifer. Comparisons between simulated data and the site activity curve indicated that the peak of the contamination had occurred before the monitoring program was initiated, generally matching concentrations along the recession limb. Probabilistic transport modeling through the water table aquifer produced a series of statistical distributions of off-site contamination. These curves further corroborated the observation that peak contamination at this site had occurred before the monitoring data were collected. A Bayesian updating technique was applied to compare the revised probabilities associated with various management alternatives and a conditional simulation was completed to define the plume configuration with some statistical confidence.
T. A. Wang, W. F. McTernan, and K. D. Willett, A Risk Based Decision Model to Optimize Remediation Choices at a Superfund Site, in <i>Superfund Risk Assessment in Soil Contamination Studies, ASTM STP 1338</i>, D. B. Hoddinott (ed.), ASTM, West Conshohocken, Pennsylvania, 1998.
T. A. Wang and W. F. McTernan, The Development and Application of a Multilevel Decision Analysis Model for the Remediation of Contaminated Groundwater Under Uncertainty, <i>Journal of Environmental Management</i>, <b>64</b>, pp. 221-235, 2002.
F. H. Chapelle, M. A. Widdowson, J. S. Brauner, E. Mendez, and C. C. Casey, Methodology for Estimating Times of Remediation Associated with Monitored Natural Attenuation, <i>U.S. Geological Survey: Water Resources Investigations Report 03-4057</i>, Columbia, South Carolina, 2003.
M. G. Green and A. J. Marr, Closure of an Unlined Evaporation Pond: A Case History, <i>Bulletin of the Association of Engineering Geologists</i>, <b>27</b>:2, pp. 235-243, 1998.
E. M. Cushing, E. H. Boswell, and R. L. Hosman, <i>General Geology of the Mississippi Embayment.</i> U.S. Geological Survey Professional Paper 448-B, 1964.
W. L. Fisher and J. H. McGowan, Depositional Systems in Wilcox Group (Eocene) of Texas and Their Occurrence of Oil and Gas, <i>The American Association of Petroleum Geologists Bulletin</i>, <b>53</b>:1, pp. 30-54, 1969.
R. L. Hosman and J. S. Weiss, Geohydrologic Units of the Mississippi Embayment and Texas Coastal Uplands Aquifer Systems, South-Central United States. U.S. Geological Survey Professional Paper 1416-B, Reston, Virginia, 1991.
G. C. Matson, <i>The Caddo Oil and Gas Field, Louisiana and Texas</i>, U.S. Geological Survey Bulletin 619, 1916.
U.S. Army Corps of Engineers (USACE). <i>Tulsa, OK District, Data Summary Report of Investigation Results from 1976 through 1992 for Burning Ground 3 and the Unlined Evaporation Pond, Longhorn Army Ammunition Plant, Karnack, Texas</i>, U.S. Army Corps of Engineers, Tulsa, Oklahoma, 1993.
M. L. Golden, A. C. Peer, and S. E. Brown, Jr., <i>Soil Survey of Harrison County, Texas.</i> Soil Conservation Service, United States Department of Agriculture, Washington, D.C., 1994.
American Petroleum Institute, <i>Decision Support System for Exposure and Risk Assessment (APIDSS) User Manual</i> (Version 1.0), American Petroleum Institute, New York, 1994.
W. A. Jury, W. F. Spencer, and W. J. Farmer, Behavior Assessment Model for Trace Organics in Soil-1, Model Description, <i>Journal of Environmental Quality</i>, <b>12</b>, pp. 558-564, 1983.
G. T. Yeh, AT123D: <i>Analytical Transient One- Two- and Three-Dimensional Simulation of Waste Transport in the Aquifer System</i>, Environmental Sciences Division Publication No. 1439, Oak Ridge National Laboratory, Oak Ridge, 1981.
R. M. Cooper and J. D. Istok, Geostatistics Applied to Groundwater Contamination. I; Methodology, <i>Journal of Environmental Engineering</i>, <b>114</b>:2, pp. 270-299, 1988.
P. Goovaerts, Geostatistical Tools for Characterizing the Spatial Variability of Microbial and Physico-Chemical Soil Properties. <i>Biology of Fertile Soils</i>, <b>27</b>, pp. 315-334, 1998.
E. Englund and A. Sparks, <i>Geostatistical Environmental Assessment Software User's Guide.</i> U.S. Environmental Protection Agency, EPA 600/8-91/008, Las Vegas, Nevada, 1991.
C. V. Deutsch, DECLUS: A FORTRAN 77 Program for Determining Optimum Spatial Declustering Weights, <i>Computers and Geosciences</i>, <b>15</b>:3, pp. 325-332, 1989.
J. P. Delhomme, Spatial Variability and Uncertainty in Groundwater Flow Parameters: A Geostatistical Approach, <i>Water Resources Research</i>, <b>15</b>:2, pp. 269-280, 1979.
M. E. Hohn, <i>Geostatistics and Petroleum Geology</i>, Van Nostrand Reinhold, New York, 1988.
J. P. Delhomme, Kriging in the Geosciences, <i>Advances in Water Resources</i>, <b>1</b>:5, pp. 251-266, 1978.
ASCE Task Committee, Review of Geostatistics in Geohydrology. I: Basic Concepts, <i>Journal of Hydraulic Engineering</i>, <b>116</b>:5, pp. 612-658, 1988.
C. V. Deutsch and A. G. Journel, <i>GSLIB Geostatistical Software Library and User's Guide.</i> Oxford University Press, New York, 1992.
J. D. Dean, P. S. Huyakorn, A. S. Donigian, K. S. Voos, R. W. Schanz, Y. J. Meeks, and R. F. Carsel, <i>Risk of Unsaturated/Saturated Transport and Transformation of Chemical Concentrations (RUSTIC). Volume 1: Theory and Code Verification.</i> U.S. Environmental Protection Agency, EPA 600/3-89/048a, Athens, Georgia, 1989.
L. Smith, R. A. Freeze, and J. Massmann, Geostatistical Approach to Site Characterization and Risk Assessment Related to Groundwater Contamination at Hazardous Waste Management Sites, in <i>Risk Assessment for Groundwater Pollution Control</i>, W. F. McTernan and E. Kaplan (eds.), American Society of Civil Engineers, New York, 1990.