About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Environmental Geosciences (DEG)

Abstract

Environmental Geosciences, V. 12, No. 4 (December 2005), P. 279-289.

Copyright copy2005. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

DOI:10.1306/eg.06070505004

Permeability estimation from transient vadose zone pumping tests in shallow coastal-plain sediments

K. L. Dixon,1 R. L. Nichols2

1Savannah River National Laboratory, Savannah River Site, 773-42A, Aiken, South Carolina 29808; [email protected]
2Savannah River National Laboratory, Savannah River Site, 773-42A, Aiken, South Carolina 29808; [email protected]

AUTHORS

Kenneth Dixon is a principal engineer at the Savannah River National Laboratory, where he has conducted research related to soil and groundwater characterization and remediation for 14 years. He received his B.S. and M.S. degrees in agricultural engineering from the University of Georgia and an M.E. degree in civil engineering from the University of South Carolina. His primary research interests are in pilot-scale testing of innovative remedial technologies and numerical modeling of contaminant fate and transport in the vadose zone.

Ralph Nichols is a fellow engineer at the Savannah River National Laboratory, where he has conducted research related to soil and groundwater characterization and remediation for 17 years. He received a B.S. degree in geological engineering from the University of Missouri–Rolla and an M.S. degree in civil engineering from the University of Oklahoma. His primary research interests are in the collection and synthesis of data from multiple scales into conceptual models that are used to develop sustainable environmental management strategies.

ACKNOWLEDGMENTS

The authors thank Charles R. Betivas for his invaluable field support. This article was prepared by the Westinghouse Savannah River Company for the U.S. Department of Energy under Contract No. DE-AC09-96SR18500.

ABSTRACT

Short-term, field-scale transient vadose zone pumping tests were performed on several wells at the Savannah River Site, located near Aiken, South Carolina. A total of 18 vacuum extraction tests were conducted in shallow coastal-plain vadose zone sediments, which yielded 38 data sets for analysis. Data collected during these tests were analyzed using two different modified Hantush-Jacob models to estimate the physical properties of the unsaturated sediments. The first model used was a commercially available software package used to estimate aquifer properties. This model assumed the test fluid (air) to be incompressible. The second model used was provided by Clemson University and accounted for the compressibility of the test fluid. This model was used primarily to provide confirmation of results from the first model. Comparisons between the results of the two models showed that both produced similar estimates of permeability for a given data set. Results from the analysis of the 38 data sets showed that the radial air permeability values ranged from 4.7 to 84.0 d. Vertical air permeability values were found to range from 0.93 to 11.7 d. The permeability values for the overlying semiconfining layer ranged from 2.7 times 10minus10 to 2.01 d. The results from these tests can be used to establish a general range of air permeabilities for shallow coastal-plain vadose zone sediments.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24