ASTM D5609-94e1

e1
Designation: D 5609 – 94
Standard Guide for
Defining Boundary Conditions in Ground-Water Flow
1
Modeling
This standard is issued under the fixed designation D 5609; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1
e NOTE—Paragraph 1.4 was added editorially October 1998.
1. Scope 3. Terminology
1.1 This guide covers the specification of appropriate 3.1 Definitions:
boundary conditions that are an essential part of conceptualiz- 3.1.1 aquifer, confined—an aquifer bounded above and
ing and modeling ground-water systems. This guide describes below by confining beds and in which the static head is above
techniques that can be used in defining boundary conditions the top of the aquifer.
and their appropriate application for modeling saturated 3.1.2 boundary—geometrical configuration of the surface
ground-water flow model simulations. enclosing the model domain.
1.2 This guide is one of a series of standards on ground- 3.1.3 boundary condition—a mathematical expression of
water flow model applications. Defining boundary conditions the state of the physical system that constrains the equations of
is a step in the design and construction of a model that is the mathematical model.
treated generally in Guide D 5447. 3.1.4 conceptual model—a simplified representation of the
1.3 This standard does not purport to address all of the hydrogeologic setting and the response of the flow system to
safety concerns, if any, associated with its use. It is the stress.
responsibility of the user of this standard to establish appro- 3.1.5 flux—the volume of fluid crossing a unit cross-
priate safety and health practices and determine the applica- sectional surface area per unit time.
bility of regulatory limitations prior to use. 3.1.6 ground-water flow model—an application of a math-
1.4 This guide offers an organized collection of information ematical model to the solution of a ground-water flow problem.
or a series of options and does not recommend a specific 3.1.7 hydraulic conductivity—(field aquifer tests), the vol-
course of action. This document cannot replace education or ume of water at the existing kinematic viscosity that will move
experience and should be used in conjunction with professional in a unit time under unit hydraulic gradient through a unit area
judgment. Not all aspects of this guide may be applicable in all measured at right angles to the direction of flow.
circumstances. This ASTM standard is not intended to repre- 3.1.8 hydrologic condition—a set of ground-water inflows
sent or replace the standard of care by which the adequacy of or outflows, boundary conditions, and hydraulic properties that
a given professional service must be judged, nor should this cause potentiometric heads to adopt a distinct pattern.
document be applied without consideration of a project’s many 3.1.9 simulation—one complete execution of the computer
unique aspects. The word “Standard” in the title of this program, including input and output.
document means only that the document has been approved 3.1.10 transmissivity—the volume of water at the existing
through the ASTM consensus process. kinematic viscosity that will move in a unit time under a unit
hydraulic gradient through a unit width of the aquifer.
2. Referenced Documents
3.1.11 unconfined aquifer—an aquifer that has a water table.
2.1 ASTM Standards: 3.1.12 For definitions of other terms used in this test
D 653 Terminology Relating to Soil, Rock, and Contained
method, see Terminology D 653.
2
Fluids
4. Significance and Use
D 5447 Guide for Application of a Ground-Water Flow
3
Model to a Site-Specific Problem 4.1 Accurate definition of boundary conditions is an essen-
tial part of conceptualizing and modeling ground-water flow
1 systems. This guide describes the properties of the most
This guide is under the jurisdiction of ASTM Committee D-18 on Soil and
common boundary conditions encountered in ground-water
Rock and is the direct responsibility of Subcommittee D18.21 on Ground Water and
Vadose Investigations.
systems and discusses major aspects of their definition and
Current edition approved Sept. 15, 1994. Published October 1994.
application in ground-water models. It also discusses the
2
Annual Book of ASTM Standards, Vol 04.08.
3
significance and specification of boundary conditions for some
Annual Book of ASTM Standards, Vol 04.09.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
D 5609
field situations and some common errors in specifying bound- 5.2.2.1 No Flow or Streamline Boundary—The no-flow or
ary conditions in ground-water models. streamline boundary is a special case of the specified flux
boundary. A streamline is a curve that is tangent t
...