ASTM D6724-01

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D 6724 – 01
Standard Guide for
Installation of Direct Push Ground Water Monitoring Wells
This standard is issued under the fixed designation D 6724; 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 1.5 This guide offers an organized collection of information
or a series of options and does not recommend a specific course
1.1 This guide describes various direct push ground water
of action. This document cannot replace education or experi-
monitoring wells and provides guidance on their selection and
ence and should be used in conjunction with professional
installation for obtaining representative ground water samples
judgement. Not all aspects of this guide may be applicable in
and monitoring water table elevations. Direct push wells are
all circumstances. This ASTM standard is not intended to
used extensively for monitoring ground water quality in
represent or replace the standard of care by which the adequacy
unconsolidated formations. This guide also includes discussion
of a given professional service must be judged, nor should this
of some groundwater sampling devices which can be perma-
document be applied without consideration of a project’s many
nently emplaced as monitoring wells.
unique aspects. The word “Standard” in the title of this
1.2 This guide does not address the single event sampling of
document means only that the document has been approved
ground water using direct push water samplers as presented in
through the ASTM consensus process.
Guide D 6001. The methods in this guide are often used with
1.6 This standard does not purport to address all of the
other tests such as direct push soil sampling (Guide D 6282)
safety concerns, if any, associated with its use. It is the
and the cone penetrometer test (Guide D 6067). The present
responsibility of the user of this standard to establish appro-
guide does not address the installation of monitoring wells by
priate safety and health practices and determine the applica-
rotary drilling methods such as those presented in Practice
bility of regulatory requirements prior to use.
D 5092. Techniques for obtaining ground water samples from
monitoring wells are covered in Guide D 4448.
2. Referenced Documents
1.3 The installation of direct push ground water monitoring
2.1 ASTM Standards:
wells is limited to unconsolidated soils and sediments includ-
D 653 Terminology Relating to Soil, Rock, and Contained
ing clays, silts, sands, and some gravels and cobbles. Penetra-
Fluids
tion may be limited, or damage may occur to equipment, in
D 4448 Guide for Sampling Ground Water Monitoring
certain subsurface conditions; some of which are discussed in
Wells
5.5. Information in this guide is limited to ground water
D 4750 Test Method for Determining Subsurface Liquid
monitoring in the saturated zone.
Levels in a Borehole or Monitoring Well (Observation
1.4 This guide does not purport to comprehensively address
Well)
all of the methods and issues associated with monitoring well
D 5088 Practice for Decontamination of Field Equipment
installation. Users should seek input from qualified profession-
Used at Non-Radioactive Waste Sites
als for the selection of proper equipment and methods that
D 5092 Practice for Design and Installation of Ground
would be the most successful for their site conditions. Other
Water Monitoring Wells in Aquifers
methods may be available for monitoring well installation, and
D 5254 Practice for Minimum Set of Data Elements
qualified professionals should have flexibility to exercise
D 5299 Guide for Decommissioning Monitoring Wells, Va-
judgement concerning alternatives not covered in this guide.
dose Zone Monitoring Devices, Boreholes, and Other
The practice described in this guide is current at the time of
Devices for Environmental Activities
issue; however, new, alternative, and innovative methods may
D 5434 Guide for Field Logging of Subsurface Explora-
become available prior to revisions. Therefore, users should
tions of Soil and Rock
consult with manufacturers or producers prior to specifying
D 5474 Guide for Selection of Data Elements for Ground
program requirements.
Water Investigation
This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock
and is the direct responsibility of Subcommittee D18.21 on Ground Water. Annual Book of ASTM Standards, Vol 04.08.
Current edition approved Nov. 10, 2001. Published January 2002. Annual Book of ASTM Standards, Vol 11.04.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6724–01
D 5521 Guide for Development of Ground Water Monitor- with regulatory requirements. The well can be developed to
ing Wells in Granular Aquifers remove mobile sediments. Water levels can be measured, and
D 5730 Guide for Site Characterization for Environmental water samples are taken as required in the sampling plan.
Purposes with Emphasis on Soil, Rock, the Vadose Zone,
and Ground Water
5. Significance and Use
D 6001 Guide for Direct Push Water Sampling for Geoen-
5.1 The direct push ground method is a rapid and economi-
vironmental Investigations
cal procedure for installing ground water monitoring wells to
D 6067 Guide for Electronic Cone Penetrometer Testing for
obtain representative ground water samples and location-
Environmental Site Characterization
specific hydrogeologic measurements. Direct push installations
D 6282 Guide for Direct Push Soil Sampling for Environ-
may offer an advantage over conventional rotary drilled
mental Site Characterization
monitoring wells (Practice D 5092) for ground water investi-
D 6286 Guide for Selection of Drilling Methods for Envi-
gations in unconsolidated formations because they reduce
ronmental Site Characterization
disturbance to the formation, and eliminate or minimize drill
D 6452 Guide for Purging Methods for Wells Used for
cuttings. At facilities where contaminated soils are present, this
Groundwater Quality Investigations
can reduce hazard exposure for operators, local personnel, and
D 6564 Guide for Field Filtration of Ground Water
the environment, and can reduce investigative derived wastes.
Samples
Additionally, smaller equipment can be used for installation,
D 6634 Guide for the Selection of Purging and Sampling
providing better access to constricted locations.
Devices for Ground Water Sampling Wells
5.2 Direct push monitoring wells generally do not extend to
depths attainable by drilling. They are also typically smaller in
3. Terminology
diameter than drilled wells, thereby reducing purge water
3.1 Terminology used within this standard is in accordance
volumes, sampling time, and investigative derived wastes.
with D 653.
Practice D 5092 monitoring wells are used when larger diam-
eters and/or sample volumes are required, or at depths to which
4. Summary of Guide
it is difficult to install direct push wells. Direct push monitoring
4.1 This guide provides information to be used by experi-
wells should be viable for monitoring for many years.
enced ground water professionals for investigation of the
5.3 Prior to construction and installation of a direct push
subsurface and ambient ground water conditions.
well or any other type of ground water well the reader should
4.2 This guide outlines a variety of field methods for
consult appropriate local and state agencies regarding regula-
installing direct push ground water monitoring wells. Installa-
tory requirements for well construction in the state. A regula-
tion methods include: (1) soil probing using combinations of
tory variance may be required for installation of direct push
dynamic (percussion or vibratory) driving with, or without,
monitoring wells in some states.
additions of static (constant) force; (2) static force from the
5.4 To date, published comparison studies between drilled
surface using hydraulic penetrometer or drilling equipment;
monitoring wells and direct push monitoring wells have shown
and (3) incremental drilling combined with direct push meth-
comparability (1, 2, 3, 4, 5). However, selection of direct push
ods. Methods for installation of annular seals and annular
monitoring wells over conventional rotary drilled wells should
grouts are also discussed as well as abandonment grouting.
be based on several criteria, such as site accessibility and
4.3 This guide addresses considerations for selection and
penetrability, stratigraphic structure, depth to groundwater, and
use of direct push well systems and installation techniques that
aquifer transmissivity.
may be classified into two main categories; exposed screen
5.5 Typical penetration depths for installation of ground
techniques and protected screen techniques. In exposed screen
water monitoring wells with direct push equipment depend on
techniques, the screened casing may serve as the drive rod, or
many variables. Some of the variables are the size and type of
may surround a drive rod that is removed following installa-
the driving system, diameter of the drive rods and monitoring
tion. In protected screen techniques, the well may be advanced
well, and the resistance of the earth materials being penetrated.
along with a protective outer casing, or may be lowered into a
Some direct push systems are capable of installing ground
driven casing that is subsequently removed. Alternatively, the
water monitoring wells to depths in excess of 100 feet, and
screen, riser, and a retractable shield may be driven simulta-
larger direct push equipment, such as the vibratory sonic type
neously and all remain in the ground.
drill (Guide D 6286) are capable of reaching much greater
4.4 The interval to be tested is determined in advance by
depths, sometimes in excess of 400 ft. However, installation
prior investigation, or by soil or water sampling during direct
depths of 10 to 50 feet are most common. Direct push methods
push driving. A screen section, either protected or unprotected,
cannot be used to install monitoring wells in consolidated
is connected to riser pipes and either driven on the outside of,
bedrock (for example, granite, limestone, gneiss), but are
or placed inside of direct push rods. With some monitoring
intended for installation in unconsolidated materials such as
well designs, it may be necessary to add sand pack and seals to
clays, silts, sands, and some gravels. Additionally, deposits
isolate the screened test zone as the rods are retracted. The top
containing significant cobbles and boulders (for example, some
of the installation is usually completed in a manner consistent
glacial deposits), or strongly cemented materials (for example,
caliche) are likely to hinder or prevent penetration to the
Annual Book of ASTM Standards, Vol 04.09. desired monitoring depth.
D6724–01
5.6 For direct push methods to provide accurate ground placed without determination of nearby geologic conditions
water monitoring results, precautions must be taken to ensure can be ineffective and possibly dangerous. Geologic investiga-
that cross-contamination by “smearing” or “drag-down” (that tions should look for perched aquifers and use installation
is, driving shallow contamination to deeper levels) does not methods which will avoid any crosscontamination of the unit.
occur, and that hydraulic connections between otherwise iso-
6.3 Environmental site characterization approaches are de-
lated water bearing strata are not created. Similar precautions
scribed in Guide D 5730. Proper site characterization for
as those applied during conventional rotary drilling operations
monitoring well placement is reviewed in Practice D 5092 on
(Guide D 6286) should be followed.
Monitoring Well Design.
5.7 There have been no conclusive comparisons of effec-
6.3.1 Characterization Tools—In geologic settings ame-
tiveness of sealing between drilled monitoring wells and direct
nable to the use of direct push ground water monitoring wells,
push monitoring wells. As with drilled monitoring wells,
other direct push methods and tools can likely also be used to
sealing methods must be carefully applied to be effective.
effectively characterize the site. For example, the Cone Pen-
5.8 Selection of direct push monitoring wells versus con-
etrometer Test (CPT) (Guide D 6067) is an effective tool for
ventional rotary drilled monitoring wells should be based on
mapping stratigraphy and locating target layers. Other sensors,
many issues. The advantages and disadvantages of the many
such as electrical conductivity and optical detectors have been
available types of driving equipment and well systems must be
placed on CPT and other direct push systems. Direct push soil
considered with regard to the specific site conditions. Specific
sampling (Guide D 6282) and water sampling (Guide D 6001)
well systems and components, as well as direct push driving
can be used in advance to locate strata of concern. Direct push
equipment, are described in Section 7.
characterization experience at a site can guide the user in well
5.9 Advantages:
design or device selection.
5.9.1 Minimally intrusive and less disturbance of the natural
6.3.2 Sampling During Installation—Many direct push sys-
formation conditions than many conventional drilling tech-
tems can take soil or water samples as part of the well
niques.
installation process. For example, two-tube systems described
5.9.2 Rapid and economical.
in direct push soil sampling Guide D 6282 can be used to
5.9.3 Smaller equipment with easier access to many loca-
collect soil samples while driving. When the target aquifer is
tions.
reached, the well screen system can be installed in the casing.
5.9.4 Use of shorter screens can eliminate connections
Sampling data taken prior to well installation can confirm the
between multiple aquifers providing better vertical definition
target stratum has been reached.
of water quality than long well screens.
6.3.3 Sampling Systems—There is a wide variety of direct
5.9.5 Generates little or potentially no contaminated drill
push ground water sampling systems which can also be used
cuttings.
for ground water monitoring. Direct push water sampling
5.9.6 Less labor intensive than most conventional drilling
Guide D 6001 describes exposed screen versus protected
techniques.
5.10 Disadvantages: screen samplers. Guide D 6282 describes the differences in
5.10.1 Cannot be used to install monitoring devices in two-tube and single-rod direct push soil sampling systems.
consolidated bedrock
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