The purpose of this Circular is to illustrate the hydrologic, geologic, and ecological concepts that must be considered to assure the wise and sustainable use of our precious ground-water resources.

The purpose of this report is to provide a brief review of selected concepts, assumptions, and uncertainties related to estimating areas contributing recharge to wells.

This Circular presents an overview of current understanding of the interaction of ground water and surface water, in terms of both quantity and quality, as applied to a variety of landscapes across the Nation.

This Circular presents an overview of current understanding of the interaction of ground water and surface water, in terms of both quantity and quality, as applied to a variety of landscapes across USA

The purpose of this publication is to provide (1) suggestions toinstructors on teaching the course outlined in Part I of the Study Guide, (2)additional references and comments on the topics in Part I of the Study Guide,and (3) answers to the exercises in Part ...

The purposes of this course are (1) to review selected fundamental aspects of ground-water flow mechanics, (2) to introduce the basic differential equations of ground-water flow and the techniques for their numerical solution, and (3) to discuss and illustrate ...

The principal purpose of this study guide is to provide a broad selectionof study materials that comprise a beginning course in ground-water hydrology, with notes and exercises

Thisreport describes the properties of the seven most common boundaryconditions encountered in ground-water systems and discusses majoraspects of their application.