ASTM D6030-96(2002)
(Guide)Standard Guide for Selection of Methods for Assessing Ground Water or Aquifer Sensitiviy and Vulnerability
Standard Guide for Selection of Methods for Assessing Ground Water or Aquifer Sensitiviy and Vulnerability
SCOPE
1.1 This guide covers information needed to select one or more methods for assessing the sensitivity of ground water or aquifers and the vulnerability of ground water or aquifers to water-quality degradation by specific contaminants.
1.2 This guide may not be all-inclusive; it offers a series of options and does not specify a course of action. It should not be used as the sole criterion or basis of comparison, and does not replace professional judgment.
1.3 This guide is to be used for evaluating sensitivity and vulnerability methods for purposes of land-use management, water-use management, ground-water protection, government regulation, and education. This guide incorporates descriptions of general classes of methods and selected examples within these classes but does not advocate any particular method.
1.4 Limitations—The utility and reliability of the methods described in this guide depend on the availability, nature, and quality of the data used for the assessment; the skill, knowledge, and judgment of the individuals selecting the method; the size of the site or region under investigation; and the intended scale of resulting map products. Because these methods are being continually developed and modified, the results should be used with caution. These techniques, whether or not they provide a specific numeric value, provide a relative ranking and assessment of sensitivity or vulnerability. However, a relatively low sensitivity or vulnerability for an area does not preclude the possibility of contamination, nor does a high sensitivity or vulnerability necessarily mean that ground water or an aquifer is contaminated.
1.5 The values stated in SI units are to be regarded as standard.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.7 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word "Standard" in the title of this document means only that the document has been approved through the ASTM consensus process.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D6030–96 (Reapproved 2002)
Standard Guide for
Selection of Methods for Assessing Ground Water or
Aquifer Sensitivity and Vulnerability
This standard is issued under the fixed designation D 6030; 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. Scope course of action. This document cannot replace education or
experienceandshouldbeusedinconjunctionwithprofessional
1.1 This guide covers information needed to select one or
judgment. Not all aspects of this guide may be applicable in all
more methods for assessing the sensitivity of ground water or
circumstances. This ASTM standard is not intended to repre-
aquifers and the vulnerability of ground water or aquifers to
sent or replace the standard of care by which the adequacy of
water-quality degradation by specific contaminants.
a given professional service must be judged, nor should this
1.2 This guide may not be all-inclusive; it offers a series of
document be applied without consideration of a project’s many
optionsanddoesnotspecifyacourseofaction.Itshouldnotbe
unique aspects. The word “Standard” in the title of this
used as the sole criterion or basis of comparison, and does not
document means only that the document has been approved
replace professional judgment.
through the ASTM consensus process.
1.3 This guide is to be used for evaluating sensitivity and
vulnerability methods for purposes of land-use management,
2. Referenced Documents
water-use management, ground-water protection, government
2.1 ASTM Standards:
regulation, and education. This guide incorporates descriptions
D 653 Terminology Relating to Soil, Rock, and Contained
of general classes of methods and selected examples within
Fluids
these classes but does not advocate any particular method.
D 5447 Guide for Application of a Ground-Water Flow
1.4 Limitations—The utility and reliability of the methods
Model to a Site-Specific Problem
described in this guide depend on the availability, nature, and
D 5490 Guide for Comparing Ground-Water Flow Model
quality of the data used for the assessment; the skill, knowl-
Simulations to Site-Specific Information
edge,andjudgmentoftheindividualsselectingthemethod;the
D 5549 Guide for the Contents of Geostatistical Site Inves-
size of the site or region under investigation; and the intended
tigation Report
scale of resulting map products. Because these methods are
D 5717 Guide for the Design of Ground-Water Monitoring
being continually developed and modified, the results should
Systems in Karst and Fractured-Rock Aquifers
be used with caution. These techniques, whether or not they
D 5880 Guide for Subsurface Flow and Transport Model-
provide a specific numeric value, provide a relative ranking
ing
and assessment of sensitivity or vulnerability. However, a
relatively low sensitivity or vulnerability for an area does not
3. Terminology
preclude the possibility of contamination, nor does a high
3.1 Definitions—Many of the terms discussed in this guide
sensitivity or vulnerability necessarily mean that ground water
arecontainedinTerminologyD 653.Thereadershouldreferto
or an aquifer is contaminated.
this guide for definitions of selected terms.
1.5 The values stated in SI units are to be regarded as
3.1.1 ground-water region, n—an extensive area where
standard.
relatively uniform geology and hydrology controls ground
1.6 This standard does not purport to address all of the
water movement.
safety concerns, if any, associated with its use. It is the
3.1.2 hydrogeologic setting, n—a composite description of
responsibility of the user of this standard to establish appro-
allthemajorgeologicandhydrologicfeatureswhichaffectand
priate safety and health practices and determine the applica-
control ground-water movement into, through, and out of an
bility of regulatory limitations prior to use.
area (1).
1.7 This guide offers an organized collection of information
3.1.3 sensitivity, n—in ground water, the potential for
or a series of options and does not recommend a specific
ground water or an aquifer to become contaminated based on
1 2
ThisguideisunderthejurisdictionofASTMCommitteeD18onSoilandRock Annual Book of ASTM Standards, Vol 04.08.
and is the direct responsibility of Subcommittee D18.21 on Ground Water and Annual Book of ASTM Standards, Vol 04.09.
Vadose Zone Investigations. The boldface numbers in parentheses refer to a list of references at the end of
Current edition approved Oct. 10, 1996. Published May 1997. this guide.
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959, United States.
D6030–96 (2002)
intrinsic hydrogeologic characteristics. Sensitivity is not de- by significant biological activity. In the United States, these
pendent on land-use practices or contaminant characteristics. typicallyincludeunconsolidatedmaterialsthatoccurtoadepth
Sensitivity is equivalent to the term 88intrinsic ground-water of2to3mor more.
vulnerability” (2).
4.3.1 In many areas, significant thicknesses of unconsoli-
3.1.3.1 Discussion—Hydrogeologic characteristics include dated materials may occur below the soil. Retardation, degra-
dation, and other chemical attenuation processes are typically
the natural properties of the soil zone, unsaturated zone, and
less than in the upper soil horizons.These underlying materials
saturated zone.
maybetheresultofdepositionalprocessesormayhaveformed
3.1.4 vulnerability, n—in ground water, the relative ease
in place by long-term weathering processes with only limited
with which a contaminant can migrate to ground water or an
biological activity. Therefore, when compiling the data re-
aquifer of interest under a given set of land-use practices,
quired for assessing ground-water sensitivity and vulnerability,
contaminant characteristics, and sensitivity conditions. Vulner-
it is important to distinguish between the soil zone and the
ability is equivalent to 88specific ground-water vulnerability.”
underlying sediments and to recognize that the two zones have
significantly different hydraulic and attenuation properties.
4. Significance and Use
4.1 Sensitivity and vulnerability methods can be applied to
5. Description of Methods
avarietyofhydrogeologicsettings,whetherornottheycontain
5.1 Hydrogeologic Settings and Scoring Methods—This
specifically identified aquifers. However, some methods are
group of methods includes those that involve geologic map-
best suited to assess ground water within aquifers, while others
ping, evaluation, and scoring of hydrogeologic characteristics
assess ground water above aquifers or ground water in areas
to produce a composite sensitivity map or composite vulner-
where aquifers have not been identified.
ability map, or both. The methods range from purely descrip-
4.1.1 Intergranular media systems, including alluvium and
tive of hydrogeologic settings to methods incorporating nu-
terrace deposits, valley fill aquifers, glacial outwash, sand-
merical scoring. They can include descriptive information or
stones, and unconsolidated coastal plain sediments are charac-
quantitative information, or both, and the maps can be applied
terized by intergranular flow, and thus generally exhibit slower
as a “filter” to exclude specific hydrogeologic units from
and more predictable ground-water velocities and directions
further consideration or select sensitive areas for further study.
than in fractured media. Such settings are amenable to assess-
5.1.1 The concept of assessing ground-water sensitivity and
ment by the methods described in this guide. Hydrologic
vulnerability is relatively recent and still developing. Thus, the
settings dominated by fracture flow or flow in solution open-
methodspresenteddifferbecausetheyhavebeendevelopedfor
ings are generally not amenable to such assessments, and
different purposes by different researchers using various types
application of these techniques to such settings may provide
of data bases in several hydrogeologic settings. These methods
misleading or totally erroneous results.
have been divided into three groups: assessments using hydro-
4.2 The methods discussed in this guide provide users with
geologic settings without scoring or rankings, assessments in
information for making land- and water-use management
which hydrogeologic setting information is combined with
decisions based on the relative sensitivity or vulnerability of
rankingorscoringofhydrologicfactors,andassessmentsusing
underlying ground water or aquifers to contamination. Most
scoring methods applied without reference to the hydrogeo-
sensitivity and vulnerability assessment methods are designed
logicsetting.Thegroupsarenotexclusivebutoverlap.Eachof
to evaluate broad regional areas for purposes of assisting
these methods produces relative, not absolute, results whether
federal, state, and local officials to identify and prioritize areas
or not it produces a numerical score. Sensitivity analyses can
where more detailed assessments are warranted, to design and
be used as the basis for a vulnerability assessment by adding
locate monitoring systems, and to help develop optimum
the information on potential point and non-point contaminant
ground-water management, use and protection policies. How-
sources.
ever, some of these methods are independent of the size of the
5.1.2 Hydrogeologic Settings, No Scoring or Ranking—
area evaluated and, therefore, can be used to evaluate the
Hydrogeologic mapping has been widely used to provide
aquifer sensitivity and vulnerability of any specific area.
aquifer sensitivity information. This subgroup of methods
4.3 Many methods for assessing ground-water sensitivity
includes those that generally present information as composite
and vulnerability require information on soils, and for some
hydrogeologic maps that can be used for multiple purposes.
types of potential ground-water contaminants, soil is the most
The maps can be used individually to make a variety of
important factor affecting contaminant movement and attenu-
land-use decisions or used as a basis for ground-water and
ation from the land surface to ground water. The relatively
aquifer sensitivity evaluations. Although derivative ground-
largesurfaceareaoftheclay-sizeparticlesinmostsoilsandthe
water and aquifer sensitivity maps can be prepared, any
soils’ content of organic matter provide sites for the retardation geologic or hydrogeologic map could potentially be used to
and degradation of contaminants. Unfortunately, there are
assess sensitivity. In settings where quantitative data are
significant differences in the definition of soil between the lacking, hydrogeologic maps can allow the same conclusions,
sciences of hydrogeology, engineering, and agronomy. For the
with the same level of confidence, as scoring methods. Hydro-
purposes of this guide, soils are considered to be those geologic settings were mapped in detail without scoring or
unconsolidated organic materials and solid mineral particles
ranking in the Denver Colorado, United States area by Hearne
that have been derived from weathering and are characterized and others (3).
D6030–96 (2002)
5.1.2.1 Sensitivity assessments based on hydrogeologic set- calculatedfromequationsbasedoncriteriaassumedtoapplyto
tings with no scoring or ranking can be used to assess different geographic areas and different hydrogeologic condi-
ground-water or aquifer vulnerability by overlaying informa- tions (1,13–14). For example, in South Dakota (15), drilling
tion on potential point or non-point contamination sources. For logs and soil survey maps were used to prepare maps based on
example, the sensitivity map included in Ref (3) has been used hydraulic conductivity which was inferred from the percent
in combination with a series of maps entitled “Land Uses and thickness of surface organic matter.Attenuation potentials
Which Affect Ground-Water Management” (4) to conduct of soil in selected Wisconsin counties (16) were mapped based
vulnerability assessments at specific sites within the greater on soil depth, permeability, drainage class, organic matter
Denver area. content, pH, and texture.
5.1.3 Hydrogeologic Settings with Ranking or Scoring, or 5.2 Process-Based Simulation Models—These methods for
Both—This group of methods includes those which assess assessment of ground-water sensitivity and vulnerability use a
variety of models, each of which simulates some combination
ground-water or aquifer sensitivity within or among various
hydrogeologic settings using specific criteria to rank or score of the physical, chemical, and biological processes that control
the movement of water and chemicals from land surface
areasbeneathwhichthegroundwateroraquifershavedifferent
potentials for becoming contaminated. The assessment is throughtheunsaturatedzonetoandthroughthesaturatedzone.
These processes are formulated in terms of equations that are
usually based on two or more hydrogeologic criteria. For
example, material texture and depth to aquifer are parameters derived theoretically or empirically. Analytical or numerical
techniques are used, usually within a computer program, to
that are commonly used to establish criteria (5-10). Criteria,
solve the equations. The solutions take the form of predicted
once defined, can then be ranked or scored, or both.
ratesofwaterandchemicalmovementasafunctionoflocation
5.1.3.1 Assessing vulnerability from point and non-point
and time. Models differ greatly in the degree of complexity
sources of potential contamination (for example, leaking tanks,
used to incorporate actual processes, the amount of data
waste generators, landfills, and abandoned hazardous waste
required, the intended scale of the application, and the domain
sites) is accomplished by mapping their location on a sensitiv-
simulated. The latter criterion is arbitrarily selected here to
ity map (for example, numerous waste-generation sites in an
categorize different simulation models. The three categories
area of low sensitivity would result in a relatively low
are: Root Zone Models, which simulate water and chemical
vulnerability rank, all other factors being equal).This mapping
movement through the portion of the unsaturated zone that is
method is particularly useful for evaluating the vulnerability of
affected by vegetation; Unsaturated Zone Models, which simu-
a large region. However, it can also be used to target smaller
late transport through the entire thickness of the unsaturated
areas of particular concern where more detail
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.