The slug test is currently the most common method for the in situ estimation of hydraulic conductivity at sites of suspected groundwater contamination. However, inappropriate procedures in one or more phases of a slug test can introduce considerable error into the resulting parameter estimates. This book remedies this problem by answering virtually every question regarding the design, performance, and analysis of slug tests. This is the first book to provide detailed information on the practical aspects of the methodology of slug tests. All major analysis methods are described in The Design, Performance, and Analysis of Slug Tests. Each analysis method is outlined in a step-by-step manner and illustrated with a field example. The major practical issues related to the field application of each technique are also discussed. This book will help the reader get more reliable parameter estimates from slug tests and increase the utility of slug test data.

The slug test can provide valuable information for hydrogeologic investigations ranging from assessments of sites of groundwater contamination to the monitoring of well deterioration through time. Inappropriate procedures in one or more phases of a test program, however, can introduce considerable error into the resulting parameter estimates. The Design, Performance, and Analysis of Slug Tests, Second Edition remedies that problem by explaining virtually all there is to know regarding the design, performance, and analysis of slug tests. The first edition has become the standard reference for all aspects of slug tests; this revised edition updates the earlier material and expands the topical coverage with new developments that have come to the fore in the intervening years between editions. Features: Describes and demonstrates the eight key steps for the performance and analysis of slug tests Presents new methods for the analysis of tests in unconfined aquifers and in highly permeable settings Expands topical coverage of LNAPL baildown tests and slug tests in small diameter wells Includes numerous flow charts that illustrate easy-to-use strategies for selection of analysis methods, and field examples demonstrate how each method should be used to get the most out of test data Offers straightforward practical guidelines that summarize the major points of each chapter Written for practicing groundwater consultants and engineers, The Design, Performance, and Analysis of Slug Tests, Second Edition will enable readers to get more reliable information from slug tests and increase the utility of this widely-used field method.

Numerical models of flow and transport processes are heavily employed in the fields of surface, soil, and groundwater hydrology. They are used to interpret field observations, analyze complex and coupled processes, or to support decision making related to large societal issues such as the water-energy nexus or sustainable water management and food production. Parameter estimation and uncertainty quantification are two key features of modern science-based predictions. When applied to water resources, these tasks must cope with many degrees of freedom and large datasets. Both are challenging and require novel theoretical and computational approaches to handle complex models with large number of unknown parameters.

The slug test can provide valuable information for hydrogeologic investigations ranging from assessments of sites of groundwater contamination to the monitoring of well deterioration through time. Inappropriate procedures in one or more phases of a test program, however, can introduce considerable error into the resulting parameter estimates. The Design, Performance, and Analysis of Slug Tests, Second Edition remedies that problem by explaining virtually all there is to know regarding the design, performance, and analysis of slug tests. The first edition has become the standard reference for all aspects of slug tests; this revised edition updates the earlier material and expands the topical coverage with new developments that have come to the fore in the intervening years between editions. Features: Describes and demonstrates the eight key steps for the performance and analysis of slug tests Presents new methods for the analysis of tests in unconfined aquifers and in highly permeable settings Expands topical coverage of LNAPL baildown tests and slug tests in small diameter wells Includes numerous flow charts that illustrate easy-to-use strategies for selection of analysis methods, and field examples demonstrate how each method should be used to get the most out of test data Offers straightforward practical guidelines that summarize the major points of each chapter Written for practicing groundwater consultants and engineers, The Design, Performance, and Analysis of Slug Tests, Second Edition will enable readers to get more reliable information from slug tests and increase the utility of this widely-used field method.

Variations in hydraulic conductivity (K) between larger scale aquifer tests and smaller scale slug tests, and within individual aquifer tests, have been linked to method bias and aquifer heterogeneity. The impacts of varying slug sizes on K, which represents K dependence on a smaller scale, is not as well understood. To examine the relationship between K and slug size, a series of slug tests with a range of initial displacements were performed in three intermediate to high K, unconfined aquifers encompassing homogeneous, mildly heterogeneous, and moderate to highly heterogeneous conditions. Slug test estimated K values at Asylum Lake are compared to K values derived from a 28-hour aquifer pumping test to examine for method bias. A statistically significant increase in hydraulic conductivity with decreasing scale, or in this case slug size, was only found at the Grand Rapids site and is likely related to turbulent energy loss in the porous media surrounding the well screen for the largest slugs. Additionally, a series of multi-well pneumatic slug tests were performed at Asylum Lake in hopes of obtaining reliable storage parameters comparable to an aquifer pumping test and testing the effect of slug size on storage parameters. Results indicate that multi-well tests can produce reliable Ss estimates representative of the aquifer. Lastly, guidelines were developed for performing pneumatic slug testing in the field using a newly designed pneumatic slug unit.

In recognition of the trend toward using numerical methdos for analyzing aquifer test data, Aquifer Test Modeling delineates the application of numerical Laplace inversion analytical equations and numerical models and demonstrates the use of public domain software. Written by a leading expert with over fifty years of experience, this highly practical text provides a thorough grounding in the terms and methods employed in aquifer test modeling, while also establishing a protocol for organizing and simplifying conceptual model definition and data analysis. Using graphs, tables, and sample datasets to enhance understanding, the author delineates the five major steps involved in the aquifer test modeling process. He discusses the importance of the conceptual model definition as a framework for organizing, simplifying, and idealizing information. The chapters cover the selection of appropriate aquifer test mathematical model equations compatible with previously defined conceptual models and highlight the importance of reviewing the mathematical assumption and the adjustment of data for any departures. They also explain format selection, technique selection, well function or drawdown calculation, and calibration. The book provides five sample data sets to assist the reader in becoming familiar with WTAQ and MODFLOW aquifer test modeling input and output data file contents with confined nonleaky and unconfined aquifer conditions. It includes conceptual models consisting of abbreviated descriptions of aquifer test facilities, aquifer test data, and aquifer parameter values together with selected sample file sets. These are just a few of the features that make the book a valuable tool for estimating the supply and contamination characteristics of aquifers.