scholarly journals Reassessing the MADE direct-push hydraulic conductivity data using a revised calibration procedure

2016 ◽  
Vol 52 (11) ◽  
pp. 8970-8985 ◽  
Author(s):  
Geoffrey C. Bohling ◽  
Gaisheng Liu ◽  
Peter Dietrich ◽  
James J. Butler
Keyword(s):  
Hydraulic Conductivity ◽  
Calibration Procedure ◽  
Conductivity Data ◽  
Direct Push

Direct Push Technology and Application to Vertical Profiling of Hydraulic Conductivity in Unconsolidated Formations

2003 ◽  
Author(s):  
Wesley McCall ◽  
Thomas M. Christy ◽  
James J. Butler
Keyword(s):  
Hydraulic Conductivity ◽  
Test Data ◽  
Small Diameter ◽  
Cost Effective ◽  
Depth Interval ◽  
Contaminant Migration ◽  
Slug Tests ◽  
Monitoring Wells ◽  
Direct Push ◽  
Vertical Profiling

Direct push (DP) methods provide a cost-effective alternative to conventional rotary drilling for investigations in unconsolidated formations. DP methods are commonly used for sampling soil gas, soil and groundwater; installing small-diameter monitoring wells; electrical logging; cone penetration testing; and standard penetration tests. Most recently, DP methods and equipment for vertical profiling of formation hydraulic conductivity (K) have been developed. Knowledge of the vertical and lateral variations in K is integral to understanding contaminant migration and, therefore, essential to designing an adequate and effective remediation system. DP-installed groundwater sampling tools may be used to access discrete intervals of the formation to conduct pneumatic slug tests. A small-diameter (38mm OD) single tube protected screen device allows the investigator to access one depth interval per advancement. Alternatively, a larger diameter (54mm OD) dual-tube groundwater profiling system may be used to access the formation at multiple depths during a single advancement. Once the appropriate tool is installed and developed, a pneumatic manifold is installed on the top of the DP rod string. The manifold includes the valving, regulator, and pressure gauge needed for pneumatic slug testing. A small-diameter pressure transducer is inserted via an airtight fitting in the pneumatic manifold, and a data-acquisition device connected to a laptop computer enables the slug test data to be acquired, displayed, and saved for analysis. Conventional data analysis methods can then be used to calculate the K value from the test data. A simple correction for tube diameter has been developed for slug tests in highly permeable aquifers. The pneumatic slug testing technique combined with DP-installed tools provides a cost-effective method for vertical profiling of K. Field comparison of this method to slug tests in conventional monitoring wells verified that this approach provides accurate K values. Use of this new approach can provide data on three-dimensional variations in hydraulic conductivity at a level of detail that has not previously been available. This will improve understanding of contaminant migration and the efficiency and quality of remedial system design, and ultimately, should lead to significant cost reductions.

Comparison of Several Interpolators for Smoothing Hydraulic Conductivity Data in South West Iran

1993 ◽  
Vol 36 (6) ◽  
pp. 1687-1693 ◽  
Author(s):  
E. Hosseini ◽  
J. Gallichand ◽  
J. Caron
Keyword(s):  
Hydraulic Conductivity ◽  
Conductivity Data ◽  
South West

Multi-scale integrated characterization of heterogeneous hydraulic and thermal properties of a deltaic aquifer

2020 ◽  
Author(s):  
Jean-Marc Ballard ◽  
Cynthia Lee ◽  
Nataline Simon ◽  
Jerome de la Bernardie ◽  
Daniel Paradis ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Hydraulic Conductivity ◽  
Fiber Optics ◽  
Tracer Test ◽  
Future Application ◽  
Quebec City ◽  
Aquifer Characterization ◽  
Characterization Methods ◽  
Direct Push ◽  
Groundwater Flux

<div>Historically, heat and temperature observations have been occasionally used to help understand aquifer systems or constrain numerical flow models. However, the development of fiber optics (FO) as part of the Distributed Temperature Sensing (DTS) technology has spun a renewed interest in the use of heat as a groundwater tracer. Recent studies have shown the possibility to carry out an active heat tracer test using fiber optics and heating cables installed by direct push and to invert the resulting thermal responses to estimate a vertical profile of groundwater fluxes. However, a better understanding of how FO-DTS results compare to other aquifer characterization methods is needed to guide its future application and integration into a practical workflow. The objective of this study was thus to compare the information provided by FO-DTS with other direct and indirect measurements used to characterize the heterogeneity of granular aquifers at multiple scales. </div><div>The multiscale integrated characterization was carried out at a heterogeneous deltaic aquifer located north of Quebec City, Canada. This aquifer has been the object of a complete hydrogeological characterization and thus provides a wide range of existing data against which the acquired data can be compared. This communication will focus on the multiscale methodology for the granular aquifer characterization including FO-DTS measurements. Based on an existing numerical hydrogeological model, three sites with a range of horizontal groundwater fluxes were selected for active FO-DTS heat tracer experiments. At one of the sites, direct push monitoring wells were also installed downstream to measure the hydraulic conductivity of the hydrofacies and the arrival of the thermal front from the heat tracer test. A previous study established a relationship between the hydrofacies of the deltaic aquifer to cone penetration test (CPT) response. As such, each FO cable and monitoring well direct-push installation was preceded by a co-located CPT. Soil cores were also taken for laboratory measurements of hydraulic and thermal properties. </div><div>The vertical profiles of groundwater fluxes from FO-DTS were found to correlate well with the relative magnitude of permeability of the hydrofacies identified with CPT profiles. FO-DTS could thus provide a qualitative or quantitative proxy for hydraulic conductivity and allow the recognition of hydrofacies at a fine scale. At the aquifer scale, the total flux measured by FO-DTS can also be compared to fluxes obtained from numerical models and thus provide a constraint to validate models. Overall, this study shows that not only does FO-DTS provide coherent results with other characterization methods, but it also adds the key measurement of groundwater flux that cannot be easily obtained by other means. FO-DTS thus has the potential to become a significant addition to existing characterization methods for granular aquifers.</div>

A constant-head pumping test method using direct-push equipment for in situ hydraulic conductivity measurements

Géotechnique ◽  
2012 ◽  
Vol 62 (3) ◽  
pp. 253-262 ◽  
Author(s):  
T. KOBAYASHI ◽  
H. ONOUE ◽  
S. OBA ◽  
N. YASUFUKU ◽  
K. OMINE
Keyword(s):  
Hydraulic Conductivity ◽  
Pumping Test ◽  
Test Method ◽  
Conductivity Measurements ◽  
Direct Push ◽  
Constant Head

A physical based model to describe effective hydraulic conductivity of the soil mixtures

2020 ◽  
Author(s):  
Deep Chandra Joshi ◽  
Mahyar Naseri ◽  
Wolfgang Durner
Keyword(s):  
Hydraulic Conductivity ◽  
Effective Conductivity ◽  
Effective Medium Theory ◽  
Mixture Component ◽  
Conductivity Data ◽  
Medium Theory ◽  
Effective Hydraulic Conductivity ◽  
Wide Range ◽  
Simple Physical Model ◽  
Soil Mixtures

<p>There is a long-lasting interest in obtaining the effective hydraulic conductivity functions of soil mixtures. The few available models to obtain hydraulic conductivity of mixtures are mostly empirical and applicable for saturated conditions. We propose a simple physical model based on the effective medium theory to calculate the effective hydraulic conductivity of soil mixtures with two or more components. The model incorporates the volumetric content of each mixture component and their hydraulic conductivity to calculate the effective conductivity of the mixture. The results of the model were compared with the measured hydraulic conductivity data obtained from the simplified evaporation method using the Hyprop device. Samples were prepared by packing homogeneous mixtures of different soil textures in cylinders with a volume of 250 cm<sup>3</sup>. Packed soil mixtures were saturated and exposed to evaporation in a climate controlled laboratory with constant air temperature and humidity. The results show an acceptable match between the measured and modeled hydraulic conductivity of the tested soil mixtures. The model can be used as a physical way to describe the effective hydraulic conductivity of mixtures in a wide range of moisture.</p>

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