FROM THE PREFACE
The approach of this book is "how-to-do and hands-on." Its purpose is to provide clear, step-by-step instruction in many of the fundamental methods of hydrogeologic investigation. These methods include both 1) the traditional techniques of data analysis, such as mathematical computation by electronic calculator and construction of graphs by hand-plotting, and 2) microcomputer techniques employing electronic spreadsheets, graphing and gridding and contouring software. The microcomputer methods employ commercial software such as Lotus 1-2-3. Microsoft Excel, Quattro-Pro, Golden Software's Grapher and Surfer, and Geraghty and Miller's AQTESOLV.
Although familiarity with any of the applications is helpful, the instructions in this manual assume no prior experience with them. Basic Hydrogeologic Methods is divided into three sections: Groundwater Occurrence and Movement, Groundwater Investigations, and Well and Aquifer Hydraulics. Each section begins with a brief summary of relevant terminology and principles. This introductory chapter is followed by a case study, which may be employed to provide a practical context for the hydrogeological methods that are described in subsequent chapters. Most of the methodological exercises culminate in an analytical product, such as data table, graph, contour map, etc., which readily serve as a focus for problem-solving activities, classroom discussions, and investigative reports. Many of the exercises present at least two investigative methods for accomplishing a particular hydrogeologic task. For example, time-drawdown graphs may be produced by a hand-plotting method or by a microcomputer method. For the professional scientist, the choice of a particular method might depend on such factors as the time available to carry out the task, the degree of accuracy required, or the availability of assessory equipment and materials. The introductory student can work through a more fundamental method (e.g., hand-plotting) before advancing to a microcomputer method (e.g., spreadsheet and graphing).
Table of Contents
Part I: Occurrence and Movement of Groundwater
Principles of Groundwater Occurrence and Movement - Case Study: Hydrogeologic Investigation of a Proposed Flyash Storage Site - Field Procedure for Measuring Depth to Water level in Wells and Piezometers - Analytical Procedure for Determining Elevation of Water Level and Depth to Water Level Below Land Surface - Method for Graphing Water Level Fluctuations - Method for Preparing Water Level Maps - Method for Preparing Flow Line Maps - Analytical Procedure for Estimating Rate of Groundwater Flow
Part II: Groundwater Investigations
Principles of Groundwater Investigations - Case Study: Siting Wells for a Public Water Supply - Method for Characterizing the Hydrogeologic Setting - Analytical Procedure for Determining Well Yield Frequency Distributions - Method for Graphing Well Yield Distributions - Method for Preparing Groundwater Availability Maps - Method for Preparing Test Well Site Maps
Part III: Aquifers and Well Hydraulics
Principles of Aquifers and Well Hydraulics - Case Study: Analysis of the Hydrogeologic Properties of an Aquifer - Field Procedure for Conducting Aquifer Tests - Analytical Procedure for Determining Time and Drawdown from Pumping Test Measurements - Method for Graphing Time-Drawdown Curves - Analytical Procedure for Estimating Hydraulic Properties of Ideal Aquifers: Theis Nonequilibrium Method - Analytical Procedure for Estimating Hydraulic Properties of Ideal Aquifers: Modified Theis Nonequilibrium (Cooper-Jacob) Method - Analytical Procedure for Estimating Hydraulic Properties of Leaky Aquifers: Hantush-Jacob Method - Analytical Procedure for Estimating Hydraulic Properties of Unconfined Aquifers: Neuman Method