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Read Full Article (file size: 1436822 bytes) Cited by
WATER RESOURCES RESEARCH,
VOL. 44,
W02432,
doi:10.1029/2007WR006078,
2008
Simulation assessment of the direct-push permeameter for characterizing vertical variations in hydraulic conductivity
Gaisheng Liu
Kansas Geological Survey, University of Kansas, Lawrence, Kansas, USA
Geoffrey C. Bohling
Kansas Geological Survey, University of Kansas, Lawrence, Kansas, USA
James J. Butler Jr.
Kansas Geological Survey, University of Kansas, Lawrence, Kansas, USA
Abstract
The direct-push permeameter (DPP) is a tool for the in situ characterization of hydraulic conductivity (K) in shallow, unconsolidated
formations. This device, which consists of a short screened section with a pair of pressure transducers near the screen, is
advanced into the subsurface with direct-push technology. K is determined through a series of injection tests conducted between
advancements. Recent field work by Butler et al. (2007) has shown that the DPP holds great potential for describing vertical
variations in K at an unprecedented level of detail, accuracy and speed. In this paper, the fundamental efficacy of the DPP
is evaluated through a series of numerical simulations. These simulations demonstrate that the DPP can provide accurate K
information under conditions commonly faced in the field. A single DPP test provides an effective K for the domain immediately
surrounding the interval between the injection screen and the most distant pressure transducer. Features that are thinner
than that interval can be quantified by reducing the vertical distance between successive tests and analyzing the data from
all tests simultaneously. A particular advantage of the DPP is that, unlike most other single borehole techniques, a low-K
skin or a clogged screen has a minimal impact on the K estimate. In addition, the requirement that only steady-shape conditions
be attained allows for a dramatic reduction in the time required for each injection test.
Received 31
March
2007;
accepted 8
October
2007;
published 22
February
2008.
Keywords: Direct-push permeameter;
hydraulic conductivity;
numerical simulation;
site characterization;
parameter estimation.
Index Terms: 1894 Hydrology: Instruments and techniques: modeling; 1829 Hydrology: Groundwater hydrology; 1828 Hydrology: Groundwater hydraulics; 1849 Hydrology: Numerical approximations and analysis.
Read Full Article (file size: 1436822 bytes) Cited by
Citation: Liu, G., G. C. Bohling, and J. J. Butler Jr.
(2008),
Simulation assessment of the direct-push permeameter for characterizing vertical variations in hydraulic conductivity,
Water Resour. Res.,
44,
W02432,
doi:10.1029/2007WR006078.
Copyright 2008 by the American Geophysical Union.
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