ASTM D5299/D5299M-18

Standard Guide for Decommissioning of Groundwater Wells, Vadose Zone Monitoring Devices, Boreholes, and Other Devices for Environmental Activities

SIGNIFICANCE AND USE
5.1 Decommissioning of boreholes and monitoring wells, and other devices requires that the specific characteristics of each site be considered. The wide variety of geological, biological, and physical conditions, construction practices, and chemical composition of the surrounding soil, rock, waste, and groundwater precludes the use of a single decommissioning practice. The procedures discussed in this guide are intended to aid the geologist or engineer in selecting the tasks needed to plan, choose materials for, and carry out an effective permanent decommissioning operation. Each individual situation should be evaluated separately and the appropriate technology applied to meet site conditions. Considerations for selection of appropriate procedures are presented in this guide, but other considerations based on site specific conditions should also be considered.
Note 6: Ideally, decommissioning should be considered as an integral part of the design of the monitoring well. Planning at this early stage can make the decommissioning activity easier to accomplish. See Practice D5092 for details on monitoring well construction.  
5.2 This guide is intended to provide technical information and is not intended to supplant statutes or regulations of local governing bodies. Approval of the appropriate regulatory authorities should be an important consideration during the decommissioning process. This practice is in general accordance with other national and state guidance documents on well decommissioning (ANSI/NGWA-01-14 [1]1 and California EPA [2].
Note 7: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results...
SCOPE
1.1 This guide covers procedures that are specifically related to permanent decommissioning (closure) of the following as applied to environmental activities. It is intended for use where solid or hazardous materials or wastes are found, or where conditions occur requiring the need for decommissioning. The following devices are considered in this guide:  
1.1.1 A borehole used for geoenvironmental purposes (see Note 1),  
1.1.2 Monitoring wells,  
1.1.3 Observation wells,  
1.1.4 Injection wells (see Note 2),  
1.1.5 Piezometers,  
1.1.6 Wells used for the extraction of contaminated groundwater, the removal of floating or submerged materials other than water such as gasoline or tetrachloroethylene, or other devices used for the extraction of soil gas,  
1.1.7 A borehole used to construct a monitoring well, and  
1.1.8 Any other well or boring that houses a vadose zone monitoring device.  
1.2 Temporary decommissioning of the above is not covered in this guide.  
Note 1: This guide may be used to decommission boreholes where no contamination is observed at a site (see Practice D420 for details); however, the primary use of the guide is to decommission boreholes and wells where solid or hazardous waste have been identified. Methods identified in this guide can also be used in other situations such as the decommissioning of water supply wells and boreholes where water contaminated with nonhazardous pollutants (such as nitrates or sulfates) are present. This guide should be consulted in the event that routine geotechnical studies indicate the presence of contamination at a site. Consult and follow national, state, or local regulations as they may control required decommissioning procedures.
Note 2: The term “well” is used in this guide to denote monitoring wells, piezometers, or other devices constructed in a manner similar to a well. Some of the devices listed such as injection and extraction wells can be decomm...

General Information

• Status: Published
• Publication Date: 14-Nov-2018
• ICS: 93.025 - External water conveyance systems
• Technical Committee: D18 - Soil and Rock
• Drafting Committee: D18.21 - Groundwater and Vadose Zone Investigations

Relations

• Replaces: ASTM D5299/D5299M-17 - Standard Guide for Decommissioning of Groundwater Wells, Vadose Zone Monitoring Devices, Boreholes, and Other Devices for Environmental Activities
• Effective Date: 15-Nov-2018
• Refers: ASTM D3740-23 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Nov-2023
• Refers: ASTM D5088-20 - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 01-May-2020
• Refers: ASTM D6286-19 - Standard Guide for Selection of Drilling and Direct Push Methods for Geotechnical and Environmental Subsurface Site Characterization
• Effective Date: 01-Oct-2019
• Refers: ASTM D3740-19 - Standard Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction
• Effective Date: 01-Oct-2019
• Refers: ASTM D6167-19 - Standard Guide for Conducting Borehole Geophysical Logging: Mechanical Caliper
• Effective Date: 01-May-2019
• Refers: ASTM D6274-18 - Standard Guide for Conducting Borehole Geophysical Logging - Gamma
• Effective Date: 15-Dec-2018
• Refers: ASTM D420-18 - Standard Guide for Site Characterization for Engineering Design and Construction Purposes
• Effective Date: 01-Feb-2018
• Refers: ASTM D5753-18 - Standard Guide for Planning and Conducting Geotechnical Borehole Geophysical Logging
• Effective Date: 01-Feb-2018
• Refers: ASTM D5782-18 - Standard Guide for Use of Direct Air-Rotary Drilling for Geoenvironmental Exploration and the Installation of Subsurface Water-Quality Monitoring Devices
• Effective Date: 01-Jan-2018
• Refers: ASTM D2487-17e1 - Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System)
• Effective Date: 15-Dec-2017
• Refers: ASTM D2487-17 - Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System)
• Effective Date: 15-Dec-2017
• Refers: ASTM D2488-17 - Standard Practice for Description and Identification of Soils (Visual-Manual Procedures)
• Effective Date: 15-Jul-2017
• Refers: ASTM D5608-16 - Standard Practices for Decontamination of Sampling and Non Sample Contacting Equipment Used at Low Level Radioactive Waste Sites
• Effective Date: 01-Feb-2016
• Refers: ASTM D5088-15a - Standard Practice for Decontamination of Field Equipment Used at Waste Sites
• Effective Date: 01-Aug-2015

Overview

ASTM D5299/D5299M-18 is the standard guide developed by ASTM International for the permanent decommissioning (closure) of groundwater wells, vadose zone monitoring devices, boreholes, and other subsurface devices used in environmental activities. The guide addresses the procedures necessary for safe, effective, and compliant closure, especially where solid, hazardous, or non-hazardous wastes have been identified. Its purpose is to assist professionals in selecting methods and materials based on specific site conditions, ensuring that abandoned wells and boreholes do not become conduits for contaminant migration or sources of environmental concern.

This standard is widely referenced by environmental consultants, remediation professionals, regulators, and engineers tasked with well closure, groundwater site assessments, and environmental site management.

Key Topics

• Scope of Devices: Covers decommissioning procedures for:

  • Boreholes for geoenvironmental purposes
  • Monitoring wells, including observation and piezometer wells
  • Wells used for extraction of contaminated groundwater and soil gas
  • Injection wells and other subsurface devices within vadose zones

• Site-Specific Considerations: Recognizes that each site may have unique geological, hydrogeological, and chemical conditions. As such, the standard provides guidance for selecting appropriate decommissioning practices, but mandates site-specific evaluation by knowledgeable professionals.

• Material Selection: Emphasizes the importance of choosing plugging materials (such as Portland cement, bentonite, and specialized grouts) with properties compatible with site geology, well materials, and potential contaminants. Plugging materials should prevent vertical or horizontal migration of fluids and have sufficient structural, chemical, and hydraulic integrity.

• Regulatory Compliance: Stresses that local, state, and national regulations may supersede the guide's recommendations. Approval by relevant environmental authorities is essential in the decommissioning process.

• Procedure Planning and Documentation: Outlines the steps from project planning to closure documentation, including assessing well history, selecting methods and materials, and ensuring records meet environmental due diligence standards.

• Quality Assurance: The standard notes that outcome quality depends on the skills of personnel, the suitability of equipment, and compliance with related standards. Organizations are encouraged to meet the competence requirements referenced in ASTM D3740.

Applications

• Environmental Remediation: Used in the closure of wells and devices located at sites with historical contamination, hazardous waste facilities, or landfills to prevent continued spread of contaminants.

• Site Redevelopment: Ensures proper abandonment of legacy wells and boreholes before property transactions, construction, or redevelopment, supporting regulatory closure and minimizing liability.

• Industrial and Agricultural Wells: Applies to permanent abandonment of wells impacted by nonhazardous pollutants such as nitrates or sulfates, as well as at sites without observed contamination.

• Hydrogeological Investigations: Supports closure following groundwater monitoring or geotechnical studies, particularly when contamination is detected or monitoring objectives have been met.

• Regulatory Programs: Assists compliance under state and federal well closure mandates within programs such as Superfund, RCRA, or similar regional environmental frameworks.

Related Standards

• ASTM D5092 - Standard for design and installation of groundwater monitoring wells (important for well construction practices affecting closure)
• ASTM D420 - Guide for site characterization for engineering and construction purposes
• ASTM D3740 - Practice for minimum requirements for agencies engaged in testing and/or inspection of soil and rock
• ANSI/NGWA-01-14 - National groundwater well construction and abandonment standard
• California EPA Guidance - State-specific well decommissioning protocols

ASTM D5299/D5299M-18 is an essential resource for environmental professionals ensuring safe, compliant, and site-appropriate decommissioning of groundwater wells and boreholes, protecting both human health and the environment from potential contaminant pathways. Always consult local regulations and involve qualified personnel throughout the closure process.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5299/D5299M − 18
Standard Guide for
Decommissioning of Groundwater Wells, Vadose Zone
Monitoring Devices, Boreholes, and Other Devices for
Environmental Activities
This standard is issued under the fixed designation D5299/D5299M; 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 (´) indicates an editorial change since the last revision or reapproval.
be decommissioned using this guide for information but are not specifi-
1. Scope*
cally covered in detail in the text.
1.1 This guide covers procedures that are specifically re-
NOTE 3—Details on the decommissioning of multiple-screened wells
latedtopermanentdecommissioning(closure)ofthefollowing
are not provided in this guide due to the many methods used to construct
these types of wells and the numerous types of commercially available
as applied to environmental activities. It is intended for use
multiple-screenedwellsystems.However,insomeinstances,themethods
where solid or hazardous materials or wastes are found, or
presentedinthisguidemaybeusedwithfewchanges.Anexampleofhow
where conditions occur requiring the need for decommission-
this guide may be used is the complete removal of the multiple-screened
ing. The following devices are considered in this guide:
wells by overdrilling.
1.1.1 A borehole used for geoenvironmental purposes (see
1.3 Most monitoring wells and piezometers are intended
Note 1),
primarily for water quality sampling, water level observation,
1.1.2 Monitoring wells,
or soil gas sampling, or combination thereof, to determine
1.1.3 Observation wells,
quality. Many wells are relatively small in diameter typically
1.1.4 Injection wells (see Note 2),
2.5 to 20 cm [1 to 8 inches] and are used to monitor for
1.1.5 Piezometers,
hazardous chemicals in groundwater. Decommissioning of
1.1.6 Wells used for the extraction of contaminated
monitoring wells is necessary to:
groundwater, the removal of floating or submerged materials
1.3.1 Eliminate the possibility that the well is used for
other than water such as gasoline or tetrachloroethylene, or
purposes other than intended,
other devices used for the extraction of soil gas,
1.3.2 Prevent migration of contaminants into an aquifer or
1.1.7 A borehole used to construct a monitoring well, and
between aquifers,
1.1.8 Any other well or boring that houses a vadose zone
1.3.3 Preventmigrationofcontaminantsinthevadosezone,
monitoring device.
1.3.4 Reduce the potential for vertical or horizontal migra-
1.2 Temporary decommissioning of the above is not cov-
tion of fluids in the well or adjacent to the well, and
ered in this guide.
1.3.5 Remove the well from active use when the well is no
NOTE 1—This guide maybeusedtodecommissionboreholeswhereno
longer capable of rehabilitation or has failed structurally; is no
contamination is observed at a site (see Practice D420 for details);
longer needed for monitoring; is no longer capable of provid-
however, the primary use of the guide is to decommission boreholes and
ing representative samples or is providing unreliable samples;
wells where solid or hazardous waste have been identified. Methods
is required to be decommissioned; or to meet regulatory
identified in this guide can also be used in other situations such as the
requirements.
decommissioning of water supply wells and boreholes where water
contaminated with nonhazardous pollutants (such as nitrates or sulfates)
NOTE 4—The determination of whether a well is providing a represen-
are present. This guide should be consulted in the event that routine
tativewaterqualitysampleisnotdefinedinthisguide.Examplesofwhen
geotechnical studies indicate the presence of contamination at a site.
a representative water quality sample may not be collected include the
Consultandfollownational,state,orlocalregulationsastheymaycontrol
biological or chemical clogging of well screens, a drop in the water level
required decommissioning procedures.
to below the base of the well screen, or complete silting of the screen.
NOTE 2—The term “well” is used in this guide to denote monitoring
These conditions may indicate that a well is not functioning correctly.
wells, piezometers, or other devices constructed in a manner similar to a
well.Someofthedeviceslistedsuchasinjectionandextractionwellscan
1.4 This guide is intended to provide information for effec-
tivepermanentclosureofwellssothatthephysicalstructureof
thewelldoesnotprovideameansofhydrauliccommunication
ThisguideisunderthejurisdictionofASTMCommitteeD18onSoilandRock
between aquifers, with above surfaces or react chemically in a
and is the direct responsibility of Subcommittee D18.21 on Groundwater and
detrimental way with the environment.
Vadose Zone Investigations.
Current edition approved Nov. 15, 2018. Published November 2018. Originally
1.5 The intent of this guide is to provide procedures that
approved in 1992. Last previous edition approved in 2017 as D5299/D5299M–17.
DOI: 10.1520/D5299_D5299M-18. when followed result in a reasonable level of confidence in the
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5299/D5299M − 18
integrityofthedecommissioningactivity.However,itmaynot D653Terminology Relating to Soil, Rock, and Contained
be practical to verify the integrity of the decommissioning Fluids
procedure.Currently,methodsarenotavailabletosubstantially
D2487Practice for Classification of Soils for Engineering
determine the integrity of the decommissioning activity. Purposes (Unified Soil Classification System)
D2488Practice for Description and Identification of Soils
1.6 This guide may also be used for closure or decommis-
(Visual-Manual Procedures)
sioning of other systems that could allow vertical or horizontal
D3740Practice for Minimum Requirements for Agencies
migration of contaminants or other cross-contamination of
Engaged in Testing and/or Inspection of Soil and Rock as
aquifers,suchasdugwells,geothermalloops,orwhenordered
Used in Engineering Design and Construction
by regulatory agencies.
D4380Test Method for Density of Bentonitic Slurries
1.7 Units—The values stated in either SI units or inch-
D5088Practice for Decontamination of Field Equipment
poundunits(giveninbrackets)aretoberegardedseparatelyas
Used at Waste Sites
standard. The values stated in each system may not be exact
D5092Practice for Design and Installation of Groundwater
equivalents;therefore,eachsystemshallbeusedindependently
Monitoring Wells
of the other. Combining values from the two systems may
D5434Guide for Field Logging of Subsurface Explorations
result in non-conformance with the standard.
of Soil and Rock
1.8 All observed and calculated values shall conform to the
D5608Practices for Decontamination of Sampling and Non
guidelines for significant digits and rounding established in
Sample Contacting Equipment Used at Low Level Radio-
Practice D6026, unless superseded by this standard.
active Waste Sites
1.9 This standard does not purport to address all of the D5753Guide for Planning and Conducting Geotechnical
safety concerns, if any, associated with its use. It is the Borehole Geophysical Logging
responsibility of the user of this standard to establish appro- D5781Guide for Use of Dual-Wall Reverse-Circulation
priate safety, health, and environmental practices and deter- Drilling for Geoenvironmental Exploration and the Instal-
mine the applicability of regulatory limitations prior to use. lation of Subsurface Water Quality Monitoring Devices
1.10 This guide offers an organized collection of informa- D5782Guide for Use of Direct Air-Rotary Drilling for
tion or a series of options and does not recommend a specific Geoenvironmental Exploration and the Installation of
course of action. This document cannot replace education or
Subsurface Water-Quality Monitoring Devices
experience and should be used in conjunction with professional D5784Guide for Use of Hollow-StemAugers for Geoenvi-
judgment. Not all aspects of this guide may be applicable in all
ronmental Exploration and the Installation of Subsurface
circumstances. This ASTM standard is not intended to repre- Water Quality Monitoring Devices
sent or replace the standard of care by which the adequacy of
D5872Guide for Use of Casing Advancement Drilling
a given professional service must be judged, nor should this Methods for Geoenvironmental Exploration and Installa-
document be applied without consideration of a project’s many
tion of Subsurface Water Quality Monitoring Devices
unique aspects. The word“ Standard” in the title of this
D5978 Guide for Maintenance and Rehabilitation of
document means only that the document has been approved
Groundwater Monitoring Wells
through the ASTM consensus process.
D6026Practice for Using Significant Digits in Geotechnical
NOTE 5—If state and local regulations are in effect where the decom-
Data
missioning is to occur, the regulations take precedence over this guide.
D6151PracticeforUsingHollow-StemAugersforGeotech-
1.11 This international standard was developed in accor-
nical Exploration and Soil Sampling
dance with internationally recognized principles on standard-
D6167Guide for Conducting Borehole Geophysical Log-
ization established in the Decision on Principles for the
ging: Mechanical Caliper
Development of International Standards, Guides and Recom-
D6274Guide for Conducting Borehole Geophysical Log-
mendations issued by the World Trade Organization Technical
ging - Gamma
Barriers to Trade (TBT) Committee.
D6282Guide for Direct Push Soil Sampling for Environ-
mental Site Characterizations
2. Referenced Documents
D6286GuideforSelectionofDrillingMethodsforEnviron-
2.1 ASTM Standards:
mental Site Characterization
C150Specification for Portland Cement
D6724Guide for Installation of Direct Push Groundwater
D420Guide for Site Characterization for Engineering De-
Monitoring Wells
sign and Construction Purposes
D422Test Method for Particle-SizeAnalysis of Soils (With-
3. Terminology
drawn 2016)
3.1 Definitions:
3.1.1 For definitions of common technical terms in this
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
standard, refer to Terminology D653.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
3.2 Definitions of Terms Specific to This Standard:
the ASTM website.
3.2.1 blowout, n—in drilling, a sudden or violent uncon-
The last approved version of this historical standard is referenced on
www.astm.org. trolled escape of fluids or gas, or both, from a borehole.
D5299/D5299M − 18
3.2.2 caliper log, n—in drilling, a geophysical borehole log 3.2.15 neat cement, n—in grouting, a mixture of Portland
that shows to scale the variations with depth in the mean Cement (C150) and water and is not extended with sand or
diameter of a cased or uncased borehole. other aggregate.
3.2.16 native material, n—in drilling, in place geologic (or
3.2.3 cement bond (sonic) log, n—in drilling, a borehole
soil) materials encountered at a site.
geophysicallogthatcanbeusedtodeterminetheeffectiveness
of a cement seal of the annular space of a well.
3.2.17 overdrilling, n—in drilling,theprocessofdrillingout
a well casing and any material placed in the annular space.
3.2.4 channeling, n—in drilling, the process of forming a
verticalcavityresultingfromafaultycementjobintheannular 3.2.18 perforation, n—in drilling, a slot or hole made in a
well casing to allow for communication of fluids between the
space.
well and the annular space.
3.2.5 curing accelerator, n—in grouting,amaterialaddedto
3.2.19 plow layer, n—in drilling,thedepthtypicallyreached
cement to decrease the time for curing.
byaploworothercommonlyusedearthturningdeviceusedin
3.2.5.1 Discussion—Examplesaresodiumchloride,calcium
agriculture.
sulfate (gypsum), and aluminum powder.
3.2.19.1 Discussion—This depth is commonly 0.3 m to 0.6
3.2.6 decommissioning (closure), n—in drilling, the engi-
m [1 to 2 ft] below land surface.
neered closure of a well, borehole, or other subsurface moni-
3.2.20 plugging material, n—in grouting,amaterialthathas
toring device sealed with plugging materials.
a hydraulic conductivity equal to or less than that of the
3.2.6.1 Discussion—Decommissioning also includes the
geologic formation(s) to be sealed.
planning and documenting of associated activities.Asynonym
3.2.20.1 Discussion—TypicalmaterialsincludePortlandce-
is abandonment.
ment and bentonite.
3.2.7 decontamination, n—in drilling,theprocessofremov-
3.2.21 pre-conditioning, n—in drilling, an activity con-
ing undesirable physical or chemical constituents, or both,
ducted prior to placing plugging material into a borehole in
from equipment to reduce the potential for cross-
order to stabilize the hole.
contamination.
3.2.22 temporary decommissioning, n—in drilling, the en-
3.2.8 fallback, n—in grouting, shrinkage, settlement, or loss gineered closure of a well intended to be returned to service at
some later date (generally no more than six months to one
of plugging material placed in a borehole or well.
year).
3.2.9 fire clay, n—in grouting, a siliceous clay rich in
3.2.22.1 Discussion—Temporary plugging should not dam-
hydrous aluminum silicates.
age the structural integrity of the well. Plugging materials
3.2.10 flow log, n—in drilling, a borehole geophysical log
consist of sand, bentonite, or other easily removed materials.
used to record vertical movement of groundwater and move-
3.3 The following terms used in this standard are available
ment of water into or out of a well or borehole and between
in Terminology D653 and are presented here for the conve-
formations within a well.
nience of the user.
3.2.11 grout, n—in grouting, material consisting of 3.3.1 bleeding—the autogenous flow of mixing water
within, or its emergence from, newly placed grout caused by
bentonite, cement, or a cement-bentonite mixture mixed with
water. the settlement of the solid materials within the mass.
3.2.11.1 Discussion—Neat grout is typically without the
4. Summary of Guide
addition of sand or other aggregates.
4.1 Information is provided on the significance of correctly
3.2.12 grout pipe, n—in drilling, a pipe or tube that is used
decommissioning boreholes and wells at sites containing or
to transport cement, bentonite, or other plugging materials
formerly containing solid or hazardous waste or hazardous
from the ground surface to a specified depth in a well or
materials or their byproducts, or that may be affected by solid
borehole.
or hazardous waste materials or their byproducts in the future.
3.2.12.1 Discussion—The material may be allowed to flow
Thisguidemaybeusedinsituationswherewaterqualityinone
freely or it may be injected under pressure. The term tremie
aquifer may be detrimental to another aquifer either above or
pipe is frequently used interchangeably.
below the aquifer. The primary purpose of decommissioning
activities is to permanently decommission the borehole or
3.2.13 hydraulic communication, n—in drilling, the migra-
monitoringdevicesothatthenaturalmigrationofgroundwater
tion of fluids from one zone to another, with reference to this
or soil vapor is not significantly influenced. Decommissioned
guide;especiallyalongacasing,groutplug,orthroughbackfill
boreholes and wells should have no adverse influence on the
materials.
local geologic setting than the original geologic setting (1) .
3.2.14 multiple-screened wells, n—in drilling, two or more
4.2 It is important to have a good understanding of the
monitoring wells situated in the same borehole. These devices
geology, hydrogeology, well construction, historic and future
can be either individual casing strings and screen set at a
specific depth, a well with screens in more than one zone, or
can consist of devices with screens with tubing or other
The boldface numbers in parentheses refer to a list of references at the end of
collecting devices attached that can collect a discrete sample. the text.
D5299/D5299M − 18
guideline in this standard.
land use, chemicals encountered, and the regulatory environ-
NOTE 9—The decommissioning of wells that intersect openings, frac-
ment for successful decommissioning to occur.
tured layers or other large openings, such as caves, can make sealing and
4.3 Various materials suitable for decommissioning bore-
decommissioning efforts difficult. The decommissioning of wells in areas
known to have these conditions should involve professionals experienced
holes and wells are discussed, including their positive and
in decommissioning in these areas.
negative attributes for decommissioning.Ageneralized proce-
dure is provided that discusses the process from planning
6. Materials
throughimplementationanddocumentation.Examplesoftypi-
6.1 Thematerialsusedforconstructionofamonitoringwell
cal practices are provided in the appendix.
or other monitoring device to be decommissioned in part
5. Significance and Use
determines how it is decommissioned. Various materials are
available for use in plugging boreholes and monitoring wells
5.1 Decommissioning of boreholes and monitoring wells,
(4). This section provides information on these materials.
and other devices requires that the specific characteristics of
each site be considered. The wide variety of geological,
6.2 Casing and Screen Materials:
biological, and physical conditions, construction practices, and
6.2.1 Various materials are used for well casing and screen.
chemicalcompositionofthesurroundingsoil,rock,waste,and
The most common materials used are: PVC, PTFE, fiberglass,
groundwater precludes the use of a single decommissioning
carbonsteel,stainlesssteel,andaluminum.Typically,thesame
practice.Theproceduresdiscussedinthisguideareintendedto
material is used for casing and screen in a well, however, in
aid the geologist or engineer in selecting the tasks needed to
some instances different materials may be used in a well to
plan,choosematerialsfor,andcarryoutaneffectivepermanent
achieve a particular purpose such as corrosion protection,
decommissioning operation. Each individual situation should
reduction of material costs, or improving the integrity of
beevaluatedseparatelyandtheappropriatetechnologyapplied
groundwater or soil vapor samples. This guide does not
to meet site conditions. Considerations for selection of appro-
specifically address the use of more than one type of casing or
priate procedures are presented in this guide, but other consid-
screen material used in a well, however, the same decommis-
erations based on site specific conditions should also be
sioning methods can frequently be used when more than one
considered.
materialisused(forexample,PVCandPTFE,orstainlesssteel
and carbon steel) in a well.
NOTE 6—Ideally, decommissioning should be considered as an integral
6.2.2 In selecting a well decommissioning method, PVC,
part of the design of the monitoring well. Planning at this early stage can
make the decommissioning activity easier to accomplish. See Practice PTFE, and fiberglass wells can be decommissioned using
D5092 for details on monitoring well construction.
similar methods as the three types of materials tend to be low
in tensile strength and easy to drill out or perforate. Appendix
5.2 This guide is intended to provide technical information
X1 provides a discussion on various procedures that can be
and is not intended to supplant statutes or regulations of local
used for the decommissioning of PVC wells and by reference
governing bodies. Approval of the appropriate regulatory
PTFE and fiberglass wells.
authorities should be an important consideration during the
6.2.3 Wells constructed of carbon steel, stainless steel, and
decommissioning process. This practice is in general accor-
heavy walled aluminum can be decommissioned using similar
dance with other national and state guidance documents on
methods as these materials tend to have a higher tensile
well decommissioning (ANSI/NGWA-01-14 [1]1 and Califor-
strengththatallowsforthecasingtoberemoved.AppendixX1
nia EPA [2].
provides a discussion on various procedures that can be used
NOTE 7—The quality of the result produced by this standard is
for the decommissioning of steel wells and by reference
dependent on the competence of the personnel performing it, and the
stainless steel and aluminum wells.
suitability of the equipment and facilities used. Agencies that meet the
criteria of D3740 are generally considered capable of competent and
6.3 Plugging Materials:
objective testing/sampling/inspection/etc. Users of this standard are cau-
6.3.1 Pluggingmaterialsshouldbecarefullychosenforwell
tioned that compliance with Practice D3740 does not in itself assure
closure to be permanent. Basic material characteristics are
reliable results. Reliable results depend on many factors, Practice D3740
providesameansofevaluatingsomeofthosefactors.PracticeD3740was listed as follows:
developed for agencies engaged in laboratory testing and/or inspection of
6.3.1.1 Plugging materials should not react with contami-
soils and rock.As such, it is not totally applicable to agencies performing
nants or adversely react with groundwater or geologic materi-
this practice. However, users of this practice should recognize that the
als.
framework of Practice D3740 is appropriate for evaluating the quality of
6.3.1.2 Plugging materials used in decommissioning wells,
an agency performing this practice. Currently, there is no known qualify-
ing national authority that inspects agencies that perform this practice.
borings, and the like should have hydraulic conductivity
NOTE 8—An extensive research program on annular sealants was
(saturatedcondition)thatiscomparabletoorlowerthanthatof
conducted from 2001 through 2009 and in subsequent years by the
the lowest hydraulic conductivity of the geologic material
Nebraska Grout Task Force (2). This research included cement and
being sealed.
bentonite grouts and the use of pellets and chips. The general finding of
the study indicates all sealing methods suffer from some shrinkage in the 6.3.1.3 Plugging materials must have sufficient structural
portion of the well in the unsaturated zone. The best grouts were
strength to withstand pressures expected from native condi-
cement-sand, bentonite chips, neat cements and bentonite slurries with
tions.
more than 20 percent solids. Especially problematic is the use of low
6.3.1.4 Plugging materials must maintain sealing capabili-
solids content bentonite slurries in the unsaturated zone leading to a
ties and not degrade due to chemical interaction, corrosion,
prohibition on their use in California (3). Regional or local regulations
may specify different sealing methods and mixtures that differ from seal dehydration,orotherphysicalorchemicalprocesses.Materials
D5299/D5299M − 18
should maintain their design characteristics for the length of 6.5 Extenders:
time contamination is present at the site.
6.5.1 Bentonite is the most commonly used material in
6.3.1.5 Plugging materials should not be susceptible to modifying cement properties. It can be added to most ASTM
cracking or shrinkage. and API cements. In decommissioning activities, the percent-
age of bentonite added is generally no more than 4 percent It
6.3.1.6 Plugging materials must be capable of being placed
atthepositioninthewellorboreholeinwhichtheyareneeded has the following effects when added to cement (5):
and must have properties that reduce their unintended move- 6.5.1.1 Lowers the hydraulic conductivity of the cement;
ment vertically and horizontally.
6.5.1.2 Increases slurry viscosity;
6.3.1.7 Plugging materials must be capable of forming a
6.5.1.3 Reduces fluid loss to the formation;
tight bond and seal with well casing and the formation.
6.5.1.4 Provides for a longer pumpability at normal pres-
6.3.1.8 Plugging materials must have properties that elimi-
sures as a result of delaying strength development;
nate leaching or erosion of the material, under the conditions
6.5.1.5 Reduces compressive strength; and
the material will be subjected. These include vertical or
6.5.1.6 Lowers resistance to chemical attack.
horizontal movement, or contact with groundwater or other
6.5.2 Bentonite increases shrinkage as it ties up large
existing conditions.
volumes of water that would normally be in the cement.
NOTE 10—The grain size of plugging material used in plugging and
6.6 Accelerators:
decommissioningoperationsconductedinareaswherethickvadosezones
6.6.1 Accelerators hasten the settling of cement and are
occur should be coarser than materials used in areas where thin vadose
useful when voids occur, or when cement plugs are to be used
zones or shallow saturated conditions occur. This is necessary as water is
nottransportedeffectivelyincoarse-grainedmaterialsundernegativepore
in the first pour. Two common materials are used; calcium
pressures. Coarse-grained materials should not be used where saturated
chloride and sodium chloride.
conditions are likely to exist during the period of time that hazardous
6.6.2 Calcium chloride is available as a powder or flake.
materials can be expected to occur at the site. It is important to determine
Flakes are the most commonly used form, as it is easy to store
the lithology and grain size (D422, D2487, D2488) distribution of
materials adjacent to the borehole or well prior to selection of plugging and can absorb some moisture without becoming lumpy (9).
materials. Well backfilling with native soils is not recommended.
Two to four percent of calcium chloride by weight is used to
NOTE 11—If coarse-grained materials are used to decommission the
achieve maximum acceleration. The use of calcium chloride
borehole or well, a layer of fine-grained material (such as cement or
should be considered when a rapid set, a decrease in viscosity,
bentonite, or both) 0.3 or 0.6 m [1 or 2 ft] thick should be placed at 3 m
and early strength are desired.
[10 ft] intervals in the borehole in the saturated zone. This layer should
extend 0.6 to 0.9 m [2 to 3 ft] above the highest expected level saturation
6.6.3 Sodium chloride can be added between 1.5 to 5
is expected based on historical information on the water table for
percent by weight of cement to reduce setting time. Maximum
unconfined aquifers.Asimilar thickness of these materials should be used
accelerationoccursataconcentrationof2to2.5percentexcept
for confined aquifers. A similar 1.5 m [5 ft] seal of a low-permeability
when higher water ratios are used (9).
material should be placed near the ground surface to reduce the potential
for entrance of fluids at the ground surface.
6.7 Retarders:
6.4 Commonly Used Materials—Subsections 6.2 and 6.3
6.7.1 Sodium chloride can be used to retard the setting of
introduced the general criteria that must be evaluated during
cement as well as accelerate the setting of cement. Fifteen to
the process of selecting the appropriate procedure and material
seventeen percent salt by weight is added to retard cement set
for plugging a specific well. Because well construction and
(9).
local geological conditions are site specific, a wide variety of
6.7.2 Other chemicals (cellulose, lignosulfates) have been
materials and procedures may be used to complete the closure.
used as retarders, but are not appropriate for decommissioning
6.4.1 Section6.4presentsareviewofthepluggingmaterials
activities without additional information on their compatibility
mostcommonlyusedtodecommissionmonitoringwells.Table
with waste and their effect on water quality. Reference (10)
1 summarizes these materials and lists the most important
indicates that sugar-derived retarders such as cellulose ligno-
considerations (positive and negative) for their use. Table 2
sulfates are destructive to cement strength and should not be
provides a comparison of sulfate resistance between ASTM
used where strength is important. Organic retarders should not
TypeVcementwithandwithoutpozzolans.Colealsoreported
be used for decommissioning activities.
resistance to various chemicals for epoxy cements (see Table
6.8 Density Improvers—The density of cement can be
3).
improvedtoincreasehydrostaticpressure.Sandcanbeusedto
6.4.2 Cement Additives—Many materials can be added to
increase density without affecting the cement chemically
cement to modify properties to meet a specific need. Cement
althoughadditionalwatermaybeneeded.Baritehasbeenused,
additives can be used to extend, accelerate, retard, increase
but may interact with waste and should not be used.
density, control fluid losses, minimize shrinkage or increase
6.9 Fluid Loss Controllers:
expansion,controlcirculationlosses,orreducefriction (5), (7).
Several of these materials have more than one use; for 6.9.1 Various organic materials such as cellulose can be
example, sodium chloride can be used to accelerate or retard used to produce a constant water to solids ratio that may have
cement. The most common cement additives are discussed in applicability when a grout is placed under pressure and water
the following subsections. Fig. 1 lists these additives and loss can occur. However, these materials may not be suitable
presents the relative impact of their use on selected perfor- for decommissioning activities, as they may contribute to
mance criteria. contamination.
D5299/D5299M − 18
TABLE 1 Properties of Common Plugging Materials
Plugging Description Positive Attributes Negative Attributes
Material
ASTM C-50 Portland
Cement
Type I Most commonly used type of cement Forms a good seal when used with High heats of hydration may be a
for plugging. bentonite in 3 to 5 percent problem in PVC-cased wells. Can
concentration. Commonly available shrink and crack; low-sulfate
and can be purchased premixed on- resistance. Should not be used in the
site. presence of strong acids or in low-pH
environments.
Type II Similar to Type I, but with a moderate Moderate heat of hydration. Moderate Somewhat slower strength
heat of hydration. resistance to sulfate. development than Type I; expensive.
Can shrink and crack. Can be difficult
to use. Should not be used in the
presence of strong acids or in low-pH
environments.
Type III High early strength. May prove useful in situations where Not a common cement. Can set very
high early strength is needed, such as quickly before decommissioning is
borehole walls that have a tendency completed. Should not be used in the
to collapse. presence of strong acids or in low-pH
environments.
Type IV Low heat of hydration. May prove useful in situations where a Not a common cement. Should not be
low heat of hydration is needed used in the presence of strong acids
or in low-pH environments.
Type V Similar to Type I or CEM IV, with high High resistance to sulfate and brine. Ultimate strength is less than Types I
resistance to sulfate and brine. Low heat of hydration. and III. Expensive; should not be used
in the presence of strong acids or in
low-pH environments. Can be difficult
to use. Can shrink or crack.
K Expansive cement. Type I or Type II Portland Cement
with additions (tricalcium sulfo
aluminate for example) to provide for
expansion. Expansion is generally in
the range from 0.05 to 0.20 percent.
Good resistance to sulfate attack.
EN 197 European Cement Types
CEM I Portland Cement. Commonly available and can be High heats of hydration may be a
purchased premixed on-site. problem in PVC-cased wells. Can
shrink and crack; low-sulfate
resistance. Should not be used in the
presence of strong acids or in low-pH
environments.
CEM II Portland-composite Cement May prove useful in situations where Dependent on the actual composition
low heat of hydration is needed utilized
CEM III Blastfurnace Cement May prove useful in situations where Dependent on the actual composition
low heat of hydration is needed utilized
CEM IV Pozzolanic Cement High resistance to sulfate and brine. Expensive; should not be used in the
Low heat of hydration. Good presence of strong acids or in low-pH
resistance to corrosive conditions and environments. Can be difficult to use.
in reducing the permeability of Can shrink or crack. Many types of
cement. materials can be used that can result
in variable results.
CEM V Composite Cement Dependent on the actual composition Dependent on the actual composition
utilized utilized
API 10
Class A Similar to ASTM Type I. Can be used to a depth of 1800 m High heats of hydration may be a
[6000 ft]. Forms a good seal when problem in PVC-cased wells. Can
used with bentonite in 3 to 5 percent shrink and crack; low-sulfate
concentration. Commonly available resistance. Should not be used in the
and can be purchased premixed on- presence of strong acids or in low-pH
site. environments.
Class B Similar to ASTM Type II. Can be used to depth of 1800 m Somewhat slower strength
[6000 ft]. Moderate heat of hydration. development than Type I; expensive.
Moderate resistance to sulfate. Can shrink and crack. Can be difficult
Available as a high-sulfate resistant to use. Should not be used in the
variety. presence of strong acids or in low-pH
environments.
Class C Similar to ASTM Type III. Can be used to a depth of 1800 m Can set very quickly before
[6000 ft]. decommissioning is completed.
Should not be used in the presence of
strong acids or in low-pH
environments. Can shrink and crack.
Class G Useful in a wide range of Can be used to a depth of 2400 m Should not be used in the presence of
temperatures and depths using [8000 ft]. Available as a sulfate- strong acids or in low-pH
accelerators or retarders. resistant variety. environments. Can shrink and crack.
D5299/D5299M − 18
TABLE 1 Continued
Class H Useful in a wide range of depths and Can be used to a depth of 2400 m Should not be used in the presence of
temperatures using accelerators or [8000 ft]. Available only as a moderate strong acids or in low-pH
retarders. sulfate type. environments. Can shrink and crack.
Class J Intended for use from a depth 3600 to Has use where very high Should not be used in the presence of
4900 m [12 000 to 16 000 ft]. temperatures and pressures occur. strong acids or in low-pH
environments. Can shrink and crack.
Pozzolanic cement Addition of siliceous materials to Good resistance to corrosive Many types of materials can be used
ASTM Type V or API Class A cement conditions and in reducing the that can result in variable results.
or CEM IV. permeability of cement.
Epoxy cements Vinyl ester resins. Good chemical resistance to acids Very expensive. Poor chemical
and bases. Can use available resistance to chlorinated hydrocarbons
equipment to place cement. and acetic acid. Should be used only
by experienced personnel. Water
accelerates curing, must use diesel oil
to precondition hole (diesel may
increase contamination of site if
hydrocarbons are a concern).
Bentonite
Pellets Granular bentonite compressed into a Uniform in size. Easy to use. Must be hydrated after placement.
tablet Produces a low permeability seal. Shrinkage may occur when desiccated
or when in contact with high
concentrations of organic compounds
(greater than 2 percent) or materials
that are strongly acidic or alkaline.
Expensive.
Chips Raw mined montmorillonite in the form Inexpensive. No mixing equipment Difficult to place. Must be hydrated
1 3
of chunks 0.60 to 2 cm [ ⁄4 to ⁄4 in.] in needed. Forms a low-permeability after placement. Less swelling than
size. seal. beneficiated bentonite. Shrinkage may
occur when desiccated when in
contact with high concentrations of
organic compounds (greater than 2
percent) or materials that are strongly
acidic or alkaline.
Granular Raw mined montmorillonite crushed Can be placed at depth in dry holes. Difficult to place in holes containing
and seared to a #8 to #20-mesh size. Forms a low-permeability seal. water as it quickly hydrates. Can
0.841 to 2.38 mm [0.331 to 0.0937 in.] bridge in hole. May desiccate when in
contact with high concentrations of
organic compounds (greater than 2
percent) or materials that are strongly
acidic or alkaline causing shrinkage.
Powdered Pulverized and seared bentonite that Used with cement to compensate for May not be a desirable plugging
passes a #200- mesh 0.074 mm shrinkage (under saturated material in deep vadose zones due to
[0.0029 in.] screen. Used as drilling conditions). Other additives can be the drying out of the material, resulting
mud or as an additive to cement. used to inhibit swelling. Retards in cracking. Difficult to place in holes
cement set; lowers heat of hydration. containing water, as it quickly
hydrates. Can bridge in hole. May
desiccate when in contact with high
concentrations of organic compounds
(greater than 2 percent) or materials
that are strongly acidic or alkaline
causing shrinkage.
High solids clay grout Powdered bentonite (#200 mesh) Does not shrink during curing. Low May not be a desirable plugging
0.074 mm [0.0029 in.] mixed with density reduces formation losses. material in deep vadose zones due to
fresh water to form a slurry with Forms a low-permeability seal that the drying out of the material, resulting
20 percent solids or more and a stays flexible as long as it is hydrated. in cracking. May desiccate when in
density of 1126 Kg/m g/L [9.4 lb/gal]. contact with high concentrations of
This would be approximately 0.9 kg [2 organic compounds (greater than
lb] of bentonite for each 3.8 L [gal] of 2 percent) or materials that are
water. strongly acidic or alkaline causing
shrinkage. A low-strength material
subject to expansion under low-
pressure differentials such as artesian
conditions.
Low solids grouts Less than 20 percent solids Easily placed and flowable Excessive shrinkage initially and over
time may lead to inadequate plugging.
6.9.2 These organic materials (fibrous materials, cellophane 6.10 Friction Reducers (Dispersants):
flakes) act to block the movement of the grout into the 6.10.1 These materials reduce friction to improve flow and
formation. It is not desirable to use these materials in decom- can be effective when the water cement ratio is reduced.
missioning activities due to their organic content that may Reduction of the water cement ratio is a method to decrease
adversely affect water quality and may not result in a good cement friction. (It is practical to reduce the amount of water
plug. added by using a dispersant (11). These materials (sodium
D5299/D5299M − 18
TABLE 2 Comparison of ASTM Type V Cement With and Without
6.11.1.2 Preformed Donuts—Commercialpreformeddonuts
A
Pozzolan Materials
consist of compressed bentonite and may have use in decom-
Percentage of
missioning activities.
Sulfate (as SO )in
Relative Degree of Water Soluble
Cement Type Water Samples,
6.11.2 Chips—Raw mined sodium montmorillonite in the
Sulfate Attack Sulfate (as SO )in
ppm
1 3
Soil, ppm
form of chunks that are 0.6 to 2 cm [ ⁄4 to ⁄4 in.] in diameter.
V Severe 0.20 to 2.00 1 500 to 10 000
Their angular shape can make it difficult to place chips to the
V (plus pozzolan) Very severe 2.00 or more 10 000 or more
desired depth in a small-diameter well or borehole without
A
See Ref (5).
bridging.
6.11.2.1 Fine-grained material resulting from the mechani-
cal breakdown during shipping may cause a problem in the
TABLE 3 List of Chemicals Reported Not to Affect Epoxy
A
placement of chips due to clumping. Fines should be screened
Cement
through a 6.4-mm [ ⁄4-in.] mesh screen before use.
Chemical Concentration, percent
6.11.2.2 The lower affinity for water that chips have allow
Hydrochloric acid 30
Sulfuric acid 25
them to fall through a water column without rapid hydration.
Chromic acid up to 10
6.11.2.3 Chips have applicability in large-diameter bore-
Nitric acid 5
holes and when carefully dropped into the hole to reduce
Hydroxide up to 20
Hypochlorite up to 6
bridging.
A
See Ref (6). 6.11.3 Granular—Raw-mined sodium montmorillonite
without any additives that has been crushed and seared to an 8
to 20-mesh size 2.38 to .841 mm [0.0937 to .0331 in.]. This
material can be placed at depth in dry holes but hydrates
quickly when placed into water. It often sticks to wet borehole
chloride, polymers, and calcium lignosulfonate) also help to
walls and bridges when placed through water. Granular mate-
reduce the energy needed to pump the grout. Polymers and
rial is recommended for use in the unsaturated zone with
calcium lignosulfonate may not be appropriate materials for
enough water added to provide adequate hydration.
decommissioning activity as they may affect water quality.
6.11.3.1 Fines can clump when in contact with water (12).
Finesresultfrommechanicalbreakdownofthematerialduring
6.11 Bentonite—Bentonite is predominantly composed of
shipping. Granular bentonite should be poured slowly to
the clay mineral sodium montmorillonite. It has the ability to
reducethepotentialforbridging.Insomesituations,apourrate
absorb large quantities of water and swell to many times its
not exceeding 22 Kg [48 lb] in 5 min has been used
original size when hydrated, and the material remains flexible.
successfully (12).
Bentonite clay may be used in any of its various forms to meet
6.11.4 Powdered—Untreated, seared, and ground bentonite
placement, strength, and sealing criteria listed in 6.3. The
that passes through a 200-mesh (0.074 mm [0.0029 in.])
amountofshrinkageorsettlingofabentonitesealisdependent
screen.Itisdesignedtobeusedindrillingfluids(muds)andas
on the percent solids of bentonite, composition of surrounding
an additive to other plugging materials such as cement.
formation and its soil moisture. Higher water to bentonite
Bentonite powder slurry can become an effective grout mate-
ratios increase the likelihood of dehydration.
rial when combined with density-increasing additives and
NOTE 12—A 20 percent or greater solids content is recommended for
swelling inhibitors. Powdered bentonite should not be placed
bentonite mixes. Bentonite/cement mixes are commercially available.
in dry form through water as it can bridge and stick to the
Users to are to follow manufacturer’s instructions. Bentonite only slurries
borehole walls.
should not be used for permanent plugging.
6.11.5 High Solids Clay Grout—This material is a blend of
6.11.1 The permeability of bentonite is very low; hydraulic
powderedpolymer-freebentoniteclaysmixedwithfreshwater
−6
conductivities of 1×10 cm/s or less can be achieved.
that forms a slurry with 20 percent solids or more by weight
However, bentonite may desiccate in the presence of high
and a density of 1.127 kg/L [9.4 lb/gal] (Note 13). The slurry
concentrations of some organic chemicals, strong acids or
sets to a low-permeable plastic grout that generates no heat of
bases, saline groundwater, or when allowed to dry, thereby
hydration and does not shrink during curing in the presence of
increasing its hydraulic conductivity. Bentonite is commer-
moisture. High solids clay grouts are commonly used for
cially available in the following forms:
borehole plugging (2).
6.11.1.1 Pellets—Pellets are made from granular powdered
NOTE13—Somestatesrequire30percentsolidsgroutwithadensityof
1.21 kg/L [10.1 lb/gal] or more.
bentonite that has been compressed into tablets, commonly 0.6
1 3
to2cm[ ⁄4 to ⁄4 in.] in diameter. Pellets have a low-moisture
6.12 Other Materials:
content, high density, and uniform size. Pellets should be
6.12.1 A number of other materials have been used for
composed of additive-free, high-swelling granular sodium
plugging:
bentonite. Correctly placed in a well or borehole, pellets
6.12.1.1 Attapulgiteclay(mayhaveapplicabilitywhenused
−6
hydrate and expand creating a low permeability (1×10
with a salt cement grout),
cm/s) plug. Pellets can be used in the saturated zone provided
6.12.1.2 Fire clay,
the length of the water column is short. The rate of pour into
the hole should not be more than 22 Kg [48 lb] of bentonite in
5 min (12). Sutton, Fred, Personal Communication, 1990.
D5299/D5299M − 18
NOTE 1—See Ref (8).
FIG. 1 Effects of Some Additives on the Physical Properties of Cement
6.12.1.3 Commercial packing materials, and missioning activity is successfully
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5299/D5299M − 17 D5299/D5299M − 18
Standard Guide for
Decommissioning of Groundwater Wells, Vadose Zone
Monitoring Devices, Boreholes, and Other Devices for
Environmental Activities
This standard is issued under the fixed designation D5299/D5299M; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This guide covers procedures that are specifically related to permanent decommissioning (closure) of the following as
applied to environmental activities. It is intended for use where solid or hazardous materials or wastes are found, or where
conditions occur requiring the need for decommissioning. The following devices are considered in this guide:
1.1.1 A borehole used for geoenvironmental purposes (see Note 1),
1.1.2 Monitoring wells,
1.1.3 Observation wells,
1.1.4 Injection wells (see Note 2),
1.1.5 Piezometers,
1.1.6 Wells used for the extraction of contaminated groundwater, the removal of floating or submerged materials other than
water such as gasoline or tetrachloroethylene, or other devices used for the extraction of soil gas,
1.1.7 A borehole used to construct a monitoring well, and
1.1.8 Any other well or boring that houses a vadose zone monitoring device.
1.2 Temporary decommissioning of the above is not covered in this guide.
NOTE 1—This guide may be used to decommission boreholes where no contamination is observed at a site (see Practice D420 for details); however,
the primary use of the guide is to decommission boreholes and wells where solid or hazardous waste have been identified. Methods identified in this guide
can also be used in other situations such as the decommissioning of water supply wells and boreholes where water contaminated with nonhazardous
pollutants (such as nitrates or sulfates) are present. This guide should be consulted in the event that a routine geotechnical study indicatesstudies indicate
the presence of contamination at a site. Consult and follow national, state, or local regulations as they may control required decommissioning procedures.
NOTE 2—The term “well” is used in this guide to denote monitoring wells, piezometers, or other devices constructed in a manner similar to a well.
Some of the devices listed such as injection and extraction wells can be decommissioned using this guide for information,information but are not
specifically covered in detail in the text.
NOTE 3—Details on the decommissioning of multiple-screened wells are not provided in this guide due to the many methods used to construct these
types of wells and the numerous types of commercially available multiple-screened well systems. However, in some instances, the methods presented
in this guide may be used with few changes. An example of how this guide may be used is the complete removal of the multiple-screened wells by
overdrilling.
1.3 Most monitoring wells and piezometers are intended primarily for water quality sampling, water level observation, or soil
gas sampling, or combination thereof, to determine quality. Many wells are relatively small in diameter typically 2.5 to 20 cm [1
to 8 in.]inches] and are used to monitor for hazardous chemicals in groundwater. Decommissioning of monitoring wells is
necessary to:
1.3.1 Eliminate the possibility that the well is used for purposes other than intended,
1.3.2 Prevent migration of contaminants into an aquifer or between aquifers,
1.3.3 Prevent migration of contaminants in the vadose zone,
1.3.4 Reduce the potential for vertical or horizontal migration of fluids in the well or adjacent to the well, and
1.3.5 Remove the well from active use when the well is no longer capable of rehabilitation,rehabilitation or has failed
structurally; is no longer needed for monitoring; is no longer capable of providing representative samples or is providing unreliable
samples; is required to be decommissioned; or to meet regulatory requirements.
This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and Vadose
Zone Investigations.
Current edition approved Dec. 15, 2017Nov. 15, 2018. Published January 2018November 2018. Originally approved in 1992. Last previous edition approved in 20122017
ɛ1
as D5299 – 99D5299/D5299M – 17.(2012) . DOI: 10.1520/D5299_D5299M-17.10.1520/D5299_D5299M-18.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5299/D5299M − 18
NOTE 4—The determination of whether a well is providing a representative water quality sample is not defined in this guide. Examples of when a
representative water quality sample may not be collected include the biological or chemical clogging of well screens, a drop in the water level to below
the base of the well screen, or complete silting of the screen. These conditions may indicate that a well is not functioning correctly.
1.4 This guide is intended to provide information for effective permanent closure of wells so that the physical structure of the
well does not provide a means of hydraulic communication between aquifers, with above surfaces,surfaces or react chemically in
a detrimental way with the environment.
1.5 The intent of this guide is to provide procedures that when followed result in a reasonable level of confidence in the integrity
of the decommissioning activity. However, it may not be practicablepractical to verify the integrity of the decommissioning
procedure. At this time, Currently, methods are not available to substantially determine the integrity of the decommissioning
activity.
1.6 This guide may also be used for closure or decommissioning of other systems that could allow vertical or horizontal
migration of contaminants or other cross-contamination of aquifers, such as dug wells, geothermal loops, or when ordered by
regulatory agencies.
1.7 Units—The values stated in either SI units or inch-pound units (given in brackets) are to be regarded separately as standard.
The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other.
Combining values from the two systems may result in non-conformance with the standard.
1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice
D6026, unless superseded by this standard.
1.9 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.10 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.
NOTE 5—If state and local regulations are in effect where the decommissioning is to occur, the regulations take precedence over this guide.
1.11 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
C150 Specification for Portland Cement
D420 Guide for Site Characterization for Engineering Design and Construction Purposes
D422 Test Method for Particle-Size Analysis of Soils (Withdrawn 2016)
D653 Terminology Relating to Soil, Rock, and Contained Fluids
D2487 Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System)
D2488 Practice for Description and Identification of Soils (Visual-Manual Procedures)
D3740 Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in
Engineering Design and Construction
D4380 Test Method for Density of Bentonitic Slurries
D5088 Practice for Decontamination of Field Equipment Used at Waste Sites
D5092 Practice for Design and Installation of Groundwater Monitoring Wells
D5434 Guide for Field Logging of Subsurface Explorations of Soil and Rock
D5608 Practices for Decontamination of Sampling and Non Sample Contacting Equipment Used at Low Level Radioactive
Waste Sites
D5753 Guide for Planning and Conducting Geotechnical Borehole Geophysical Logging
D5781 Guide for Use of Dual-Wall Reverse-Circulation Drilling for Geoenvironmental Exploration and the Installation of
Subsurface Water Quality Monitoring Devices
D5782 Guide for Use of Direct Air-Rotary Drilling for Geoenvironmental Exploration and the Installation of Subsurface
Water-Quality Monitoring Devices
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
D5299/D5299M − 18
D5784 Guide for Use of Hollow-Stem Augers for Geoenvironmental Exploration and the Installation of Subsurface Water
Quality Monitoring Devices
D5872 Guide for Use of Casing Advancement Drilling Methods for Geoenvironmental Exploration and Installation of
Subsurface Water Quality Monitoring Devices
D5875 Guide for Use of Cable-Tool Drilling and Sampling Methods for Geoenvironmental Exploration and Installation of
Subsurface Water Quality Monitoring Devices
D5876 Guide for Use of Direct Rotary Wireline Casing Advancement Drilling Methods for Geoenvironmental Exploration and
Installation of Subsurface Water-Quality Monitoring Devices
D5978 Guide for Maintenance and Rehabilitation of Groundwater Monitoring Wells
D6026 Practice for Using Significant Digits in Geotechnical Data
D6151 Practice for Using Hollow-Stem Augers for Geotechnical Exploration and Soil Sampling
D6167 Guide for Conducting Borehole Geophysical Logging: Mechanical Caliper
D6274 Guide for Conducting Borehole Geophysical Logging - Gamma
D6282 Guide for Direct Push Soil Sampling for Environmental Site Characterizations
D6286 Guide for Selection of Drilling Methods for Environmental Site Characterization
D6724 Guide for Installation of Direct Push Groundwater Monitoring Wells
D6725 Practice for Direct Push Installation of Prepacked Screen Monitoring Wells in Unconsolidated Aquifers
E11 Specification for Woven Wire Test Sieve Cloth and Test Sieves
F480 Specification for Thermoplastic Well Casing Pipe and Couplings Made in Standard Dimension Ratios (SDR), SCH 40 and
SCH 80
3. Terminology
3.1 Definitions:
3.1.1 For definitions of common technical terms in this standard, refer to Terminology D653.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 blowout, n—in drilling, a sudden or violent uncontrolled escape of fluids or gas, or both, from a borehole.
3.2.2 caliper log, n—in drilling, a geophysical borehole log that shows to scale the variations with depth in the mean diameter
of a cased or uncased borehole.
3.2.3 cement bond (sonic) log, n—in drilling, a borehole geophysical log that can be used to determine the effectiveness of a
cement seal of the annular space of a well.
3.2.4 channeling, n—in drilling, the process of forming a vertical cavity resulting from a faulty cement job in the annular space.
3.2.5 curing accelerator, n—in grouting, a material added to cement to decrease the time for curing.
3.2.5.1 Discussion—
Examples are sodium chloride, calcium sulfate (gypsum), and aluminum powder.
3.2.6 curing retarder, n—in grouting, a material added to cement to increase the time for curing.
3.2.6.1 Discussion—
Sodium chloride in high concentrations is an example.
3.2.6 decommissioning (closure), n—in drilling, the engineered closure of a well, borehole, or other subsurface monitoring
device sealed with plugging materials.
3.2.6.1 Discussion—
Decommissioning also includes the planning and documenting of associated activities. A synonym is abandonment.
3.2.7 decontamination, n—in drilling, the process of removing undesirable physical or chemical constituents, or both, from
equipment to reduce the potential for cross-contamination.
3.2.8 fallback, n—in grouting, shrinkage, settlement, or loss of plugging material placed in a borehole or well.
3.2.9 fire clay, n—in grouting, a silicioussiliceous clay rich in hydrous aluminum silicates.
3.2.10 flow log, n—in drilling, a borehole geophysical log used to record vertical movement of groundwater and movement of
water into or out of a well or borehole and between formations within a well.
D5299/D5299M − 18
3.2.11 geophysical borehole log, grout, n—a login grouting, obtained by lowering an instrument into a borehole and
continuously recording a physical property of native or backfill material and contained fluids. material consisting of bentonite,
cement, or a cement-bentonite mixture mixed with water.
3.2.11.1 Discussion—
Examples include resistivity, induction, caliper, sonic, and natural gamma logs.Neat grout is typically without the addition of sand
or other aggregates.
3.2.12 grout pipe, n—in drilling, a pipe or tube that is used to transport cement, bentonite, or other plugging materials from the
ground surface to a specified depth in a well or borehole.
3.2.12.1 Discussion—
The material may be allowed to flow freely or it may be injected under pressure. The term tremie pipe is frequently used
interchangeably.
3.2.13 hydraulic communication, n—in drilling, the migration of fluids from one zone to another, with reference to this guide;
especially along a casing, grout plug, or through backfill materials.
3.2.14 multiple-screened wells, n—in drilling, two or more monitoring wells situated in the same borehole. These devices can
be either individual casing strings and screen set at a specific depth, a well with screens in more than one zone, or can consist of
devices with screens with tubing or other collecting devices attached that can collect a discrete sample.
3.2.15 neat cement, n—in grouting, a mixture of Portland Cement (C150) and water and is not extended with sand or other
aggregate.
3.2.16 native material, n—in drilling, in place geologic (or soil) materials encountered at a site.
3.2.17 overdrilling, n—in drilling, the process of drilling out a well casing and any material placed in the annular space.
3.2.18 perforation, n—in drilling, a slot or hole made in a well casing to allow for communication of fluids between the well
and the annular space.
3.2.18 permanent plugging (Closing) (Sealing), n—in grouting, a seal that has a hydraulic conductivity that is equivalent or less
than the hydraulic conductivity of the geologic formation. This term is often used with uncased boreholes.
3.2.19 plow layer, n—in drilling, the depth typically reached by a plow or other commonly used earth turning device used in
agriculture.
3.2.19.1 Discussion—
This depth is commonly one to two feet (.3 m to .6 m)0.3 m to 0.6 m [1 to 2 ft] below land surface.
3.2.20 plugging material, n—in grouting, a material that has a hydraulic conductivity equal to or less than that of the geologic
formation(s) to be sealed.
3.2.20.1 Discussion—
Typical materials include portlandPortland cement and bentonite.
3.2.21 pre-conditioning, n—in drilling, an activity conducted prior to placing plugging material into a borehole in order to
stabilize the hole.
3.2.22 temporary decommissioning, n—in drilling, the engineered closure of a well intended to be returned to service at some
later date (generally no more than six months to one year).
3.2.22.1 Discussion—
Temporary plugging should not damage the structural integrity of the well. Plugging materials consist of sand, bentonite, or other
easily removed materials.
3.3 The following terms used in this standard are available in Terminology D653 and are presented here for the convenience
of the user.
3.3.1 bleeding—the autogenous flow of mixing water within, or its emergence from, newly placed grout caused by the
settlement of the solid materials within the mass.
D5299/D5299M − 18
4. Summary of Guide
4.1 Information is provided on the significance of correctly decommissioning boreholes and wells at sites containing or formerly
containing solid or hazardous waste or hazardous materials or their byproducts, or that may be affected by solid or hazardous waste
materials or their byproducts in the future. This guide may be used in situations where water quality in one aquifer may be
detrimental to another aquifer either above or below the aquifer. The primary purpose of decommissioning activities is to
permanently decommission the borehole or monitoring device so that the natural migration of groundwater or soil vapor is not
significantly influenced. Decommissioned boreholes and wells should have no adverse influence on the local geologic setting than
the original geologic setting (1) .
4.2 It is important to have a good understanding of the geology, hydrogeology, well construction, historic and future land use,
chemicals encountered, and the regulatory environment for successful decommissioning to occur.
4.3 Various materials suitable for decommissioning boreholes and wells are discussed, including their positive and negative
attributes for decommissioning. A generalized procedure is provided that discusses the process from planning through
implementation and documentation. Examples of typical practices are provided in the appendix.
5. Significance and Use
5.1 Decommissioning of boreholes and monitoring wells, and other devices requires that the specific characteristics of each site
be considered. The wide variety of geological, biological, and physical conditions, construction practices, and chemical
composition of the surrounding soil, rock, waste, and groundwater precludes the use of a single decommissioning practice. The
procedures discussed in this guide are intended to aid the geologist or engineer in selecting the tasks needed to plan, choose
materials for, and carry out an effective permanent decommissioning operation. Each individual situation should be evaluated
separately and the appropriate technology applied to meet site conditions. Considerations for selection of appropriate procedures
are presented in this guide, but other considerations based on site specific conditions should also be taken into account.considered.
NOTE 6—Ideally, decommissioning should be considered as an integral part of the design of the monitoring well. Planning at this early stage can make
the decommissioning activity easier to accomplish. See Practice D5092 for details on monitoring well construction.
5.2 This guide is intended to provide technical information and is not intended to supplant statutes or regulations of local
governing bodies. Approval of the appropriate regulatory authorities should be an important consideration during the
decommissioning process. This practice is in general accordance with other national and state guidance documents on well
decommissioning (ANSI/NGWA-01-14 [1]1 and California EPA [2].
NOTE 7—The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the
equipment and facilities used. Agencies that meet the criteria of D3740 are generally considered capable of competent and objective testing/sampling/
inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend
on many factors, Practice D3740 provides a means of evaluating some of those factors. Practice D3740 was developed for agencies engaged in laboratory
testing and/or inspection of soils and rock. As such, it is not totally applicable to agencies performing this practice. However, users of this practice should
recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this practice. CurrentCurrently, there
is no known qualifying national authority that inspects agencies that perform this practice.
NOTE 8—An extensive research program on annular sealants was conducted from 2001 through 2009 and in subsequent years by the Nebraska Grout
Task Force (2). This research included cement and bentonite grouts and the use of pellets and chips. The general finding of the study indicates all sealing
methods suffer from some shrinkage in the portion of the well in the unsaturated zone. The best grouts were cement-sand, bentonite chips, neat cements
and bentonite slurries with more than 20% 20 percent solids. Especially problematic is the use of low solids content bentonite slurries in the unsaturated
zone leading to a prohibition on their use in California (3). The bentonite slurries used in this standard are high solids slurries with more than 20% solids
and bentonite slurry is not recommended in the unsaturated zone regardless of solids content. Regional or local regulations may specify different sealing
methods and mixtures that differ from seal guideline in this standard. Regional or local regulations for mixtures of bentonite and cement slurries may
differ from this standard and may control mixture requirements. This practice is in general accordance with other national and state guidance documents
on well decommissioning (ANSI/NGWA-01-14 [1]1 and California EPA [2].
NOTE 9—The decommissioning of wells that intersect openings, fractured layers or other large openings, such as caves, can make sealing and
decommissioning efforts difficult. The decommissioning of wells in areas known to have these conditions should involve professionals experienced in
decommissioning in these areas.
6. Materials
6.1 The materials used for construction of a monitoring well or other monitoring device to be decommissioned in part
determines how it is decommissioned. Various materials are available for use in plugging boreholes and monitoring wells (4). This
section provides information on these materials.
6.2 Casing and Screen Materials:
6.2.1 Various materials are used for well casing and screen. The most common materials used are: PVC, PTFE, fiberglass,
carbon steel, stainless steel, and aluminum. Typically, the same material is used for casing and screen in a well, however, in some
instances different materials may be used in a well to achieve a particular purpose such as corrosion protection, reduction of
material costs, or improving the integrity of groundwater or soil vapor samples. This guide does not specifically address the use
The boldface numbers in parentheses refer to a list of references at the end of the text.
D5299/D5299M − 18
of more than one type of casing or screen material used in a well, however, the same decommissioning methods can frequently
be used when more than one material is used (for example, PVC and PTFE, or stainless steel and carbon steel) in a well.
6.2.2 In selecting a well decommissioning method, PVC, PTFE, and fiberglass wells can be decommissioned using similar
methods as the three types of materials tend to be low in tensile strength and easy to drill out or perforate. Appendix X1 provides
a discussion on various procedures that can be used for the decommissioning of PVC wells and by reference PTFE and fiberglass
wells.
6.2.3 Wells constructed of carbon steel, stainless steel, and heavy walled aluminum can be decommissioned using similar
methods as these materials tend to have a higher tensile strength that allows for the casing to be removed. Appendix X1 provides
a discussion on various procedures that can be used for the decommissioning of steel wells and by reference stainless steel and
aluminum wells.
6.3 Plugging Materials:
6.3.1 Plugging materials should be carefully chosen for well closure to be permanent. Basic material characteristics are listed
as follows:
6.3.1.1 Plugging materials should not react with contaminants or adversely react with groundwater or geologic materials.
6.3.1.2 Plugging materials used in decommissioning wells, borings, and the like,like should have hydraulic conductivity
(saturated condition) that is comparable to or lower than that of the lowest hydraulic conductivity of the geologic material being
sealed.
6.3.1.3 Plugging materials must have sufficient structural strength to withstand pressures expected from native conditions.
6.3.1.4 Plugging materials must maintain sealing capabilities and not degrade due to chemical interaction, corrosion,
dehydration, or other physical or chemical processes. Materials should maintain their design characteristics for the length of time
contamination is present at the site.
6.3.1.5 Plugging materials should not be susceptible to cracking or shrinkage.
6.3.1.6 Plugging materials must be capable of being placed at the position in the well or borehole in which they are needed and
must have properties that reduce their unintended movement vertically and horizontally.
6.3.1.7 Plugging materials must be capable of forming a tight bond and seal with well casing and the formation.
6.3.1.8 Plugging materials must have properties that eliminate leaching or erosion of the material, under the conditions the
material will be subjected. These include vertical or horizontal movement, or contact with groundwater or other existing
conditions.
NOTE 10—The grain size of plugging material used in plugging and decommissioning operations conducted in areas where thick vadose zones occur
should be coarser than materials used in areas where thin vadose zones or shallow saturated conditions occur. This is necessary as water is not transported
effectively in coarse-grained materials under negative pore pressures. Coarse-grained materials should not be used where saturated conditions are likely
to exist during the period of time that hazardous materials can be expected to occur at the site. It is important to determine the lithology and grain size
(D422, D2487, D2488) distribution of materials adjacent to the borehole or well prior to selection of plugging materials. Well backfilling with native soils
is not recommended.
NOTE 11—If coarse-grained materials are used to decommission the borehole or well, a layer of fine-grained material (such as cement or bentonite,
or both) .30.3 or .60.6 m [1 or 2 ft] thick should be placed at 3 m [10 ft] intervals in the borehole in the saturated zone. This layer should extend .60.6
to .90.9 m [2 to 3 ft] above the highest expected level saturation is expected based on historical information on the water table for unconfined aquifers.
A similar thickness of these materials should be used for confined aquifers. A similar 1.5-m [5-ft] 1.5 m [5 ft] seal of a low-permeability material should
be placed near the ground surface to reduce the potential for entrance of fluids at the ground surface.
6.4 Commonly Used Materials—Subsections 6.2 and 6.3 introduced the general criteria that must be evaluated during the
process of selecting the appropriate procedure and material for plugging a specific well. Because well construction and local
geological conditions are site specific, a wide variety of materials and procedures may be used to complete the closure.
6.4.1 Section 6.4 presents a review of the plugging materials most commonly used to decommission monitoring wells. Table
1 summarizes these materials and lists the most important considerations (positive and negative) for their use. A detailed discussion
of each material is presented in the following subsections.
6.4.2 Portland Cement—Portland cement may be used in any of its various forms to meet placement, strength, and durability
criteria listed in 6.1. The amount of shrinkage or settling of neat cement is dependent on the amount of water used. Higher water
to cement ratios tend to increase shrinkage (5), (6).
NOTE 12—A typical cement based grout consists of water and cement with the water/cement ratio between .44 and .53. Any excess water will cause
bleed water and excessive shrinkage. The use of additives may decrease the amount of water required for neat cements and the further reduce the amount
of shrinkage during setting.
6.5 Specification C150:
6.5.1 Type 1—Type 1 cement, a general-purpose material, is the most commonly used cement. This material has a tendency to
develop a relatively high heat of hydration when used in confined situations and has relatively low-sulfate resistance.
6.5.2 Type II—Somewhat slower strength development than Type I; however, Type II cement has moderate heat of hydration
and moderate sulfate resistance.
6.5.3 Type III—Type III cement is used when high early strength is desired. This material is not commonly used in
decommissioning activities because of its ability to quickly set. Care must be used in working with this material.
D5299/D5299M − 18
TABLE 1 Properties of Common Plugging Materials
Plugging Description Positive Attributes Negative Attributes
Material
ASTM C-50 Portland
Cement
Type I Most commonly used type of cement Forms a good seal when used with High heats of hydration may be a
for plugging. bentonite in 3 to 5 % concentration. problem in PVC-cased wells. Can
Commonly available and can be shrink and crack; low-sulfate
purchased premixed on-site. resistance. Should not be used in the
presence of strong acids or in low-pH
environments.
Type I Most commonly used type of cement Forms a good seal when used with High heats of hydration may be a
for plugging. bentonite in 3 to 5 percent problem in PVC-cased wells. Can
concentration. Commonly available shrink and crack; low-sulfate
and can be purchased premixed on- resistance. Should not be used in the
site. presence of strong acids or in low-pH
environments.
Type II Similar to Type I, but with a moderate Moderate heat of hydration. Moderate Somewhat slower strength
heat of hydration. resistance to sulfate. development than Type I; expensive.
Can shrink and crack. Can be difficult
to use. Should not be used in the
presence of strong acids or in low-pH
environments.
Type III High early strength. May prove useful in situations where Not a common cement. Can set very
high early strength is needed, such as quickly before decommissioning is
borehole walls that have a tendency completed. Should not be used in the
to collapse. presence of strong acids or in low-pH
environments.
Type IV Low heat of hydration. May prove useful in situations where a Not a common cement. Should not be
low heat of hydration is needed used in the presence of strong acids
or in low-pH environments.
Type V Similar to Type I, with high resistance High resistance to sulfate and brine. Ultimate strength is less than Types I
to sulfate and brine. Low heat of hydration. and III. Expensive; should not be used
in the presence of strong acids or in
low-pH environments. Can be difficult
to use. Can shrink or crack.
Type V Similar to Type I or CEM IV, with high High resistance to sulfate and brine. Ultimate strength is less than Types I
resistance to sulfate and brine. Low heat of hydration. and III. Expensive; should not be used
in the presence of strong acids or in
low-pH environments. Can be difficult
to use. Can shrink or crack.
K Expansive cement. Basically Type I or Type II Portland
Cement with additions (tricalcium sulfo
aluminate for example) to provide for
expansion. Expansion is generally in
the range from 0.05 to 0.20 % Good
resistance to sulfate attack.
K Expansive cement. Type I or Type II Portland Cement
with additions (tricalcium sulfo
aluminate for example) to provide for
expansion. Expansion is generally in
the range from 0.05 to 0.20 percent.
Good resistance to sulfate attack.
EN 197 European Cement Types
CEM I Portland Cement. Commonly available and can be High heats of hydration may be a
purchased premixed on-site. problem in PVC-cased wells. Can
shrink and crack; low-sulfate
resistance. Should not be used in the
presence of strong acids or in low-pH
environments.
CEM II Portland-composite Cement May prove useful in situations where Dependent on the actual composition
low heat of hydration is needed utilized
CEM III Blastfurnace Cement May prove useful in situations where Dependent on the actual composition
low heat of hydration is needed utilized
CEM IV Pozzolanic Cement High resistance to sulfate and brine. Expensive; should not be used in the
Low heat of hydration. Good presence of strong acids or in low-pH
resistance to corrosive conditions and environments. Can be difficult to use.
in reducing the permeability of Can shrink or crack. Many types of
cement. materials can be used that can result
in variable results.
CEM V Composite Cement Dependent on the actual composition Dependent on the actual composition
utilized utilized
API 10
6.5.4 Type IV—Type IV cement is used where a low heat of hydration is desired. It is not commonly used in decommissioning
activities.
D5299/D5299M − 18
TABLE 1 Continued
Class A Similar to ASTM Type I. Can be used to a depth of 1800 m High heats of hydration may be a
[6000 ft]. Forms a good seal when problem in PVC-cased wells. Can
used with bentonite in 3 to 5 % shrink and crack; low-sulfate
concentration. Commonly available resistance. Should not be used in the
and can be purchased premixed on- presence of strong acids or in low-pH
site. environments.
Class A Similar to ASTM Type I. Can be used to a depth of 1800 m High heats of hydration may be a
[6000 ft]. Forms a good seal when problem in PVC-cased wells. Can
used with bentonite in 3 to 5 percent shrink and crack; low-sulfate
concentration. Commonly available resistance. Should not be used in the
and can be purchased premixed on- presence of strong acids or in low-pH
site. environments.
Class B Similar to ASTM Type II. Can be used to depth of 1800 m Somewhat slower strength
[6000 ft]. Moderate heat of hydration. development than Type I; expensive.
Moderate resistance to sulfate. Can shrink and crack. Can be difficult
Available as a high-sulfate resistant to use. Should not be used in the
variety. presence of strong acids or in low-pH
environments.
Class C Similar to ASTM Type III. Can be used to a depth of 1800 m Can set very quickly before
[6000 ft]. decommissioning is completed.
Should not be used in the presence of
strong acids or in low-pH
environments. Can shrink and crack.
Class G Useful in a wide range of Can be used to a depth of 2400 m Should not be used in the presence of
temperatures and depths through the [8000 ft]. Available as a sulfate- strong acids or in low-pH
use of accelerators or retarders. resistant variety. environments. Can shrink and crack.
Class G Useful in a wide range of Can be used to a depth of 2400 m Should not be used in the presence of
temperatures and depths using [8000 ft]. Available as a sulfate- strong acids or in low-pH
accelerators or retarders. resistant variety. environments. Can shrink and crack.
Class H Useful in a wide range of depths and Can be used to a depth of 2400 m Should not be used in the presence of
temperatures through the use of [8000 ft]. Available only as a moderate strong acids or in low-pH
accelerators or retarders. sulfate type. environments. Can shrink and crack.
Class H Useful in a wide range of depths and Can be used to a depth of 2400 m Should not be used in the presence of
temperatures using accelerators or [8000 ft]. Available only as a moderate strong acids or in low-pH
retarders. sulfate type. environments. Can shrink and crack.
Class J Intended for use from a depth 3600 to Has use where very high Should not be used in the presence of
4900 m [12 000 to 16 000 ft]. temperatures and pressures occur. strong acids or in low-pH
environments. Can shrink and crack.
Pozzolanic cement Addition of silicious materials to ASTM Good resistance to corrosive Many types of materials can be used
Type V or API Class A cement. conditions and in reducing the that can result in variable results.
permeability of cement.
Pozzolanic cement Addition of siliceous materials to Good resistance to corrosive Many types of materials can be used
ASTM Type V or API Class A cement conditions and in reducing the that can result in variable results.
or CEM IV. permeability of cement.
Epoxy cements Vinyl ester resins. Good chemical resistance to acids Very expensive. Poor chemical
and bases. Can use available resistance to chlorinated hydrocarbons
equipment to place cement. and acetic aid. Should be used only
by experienced personnel. Water
accelerates curing, must use diesel oil
to precondition hole (diesel may
increase contamination of site if
hydrocarbons are a concern).
Epoxy cements Vinyl ester resins. Good chemical resistance to acids Very expensive. Poor chemical
and bases. Can use available resistance to chlorinated hydrocarbons
equipment to place cement. and acetic acid. Should be used only
by experienced personnel. Water
accelerates curing, must use diesel oil
to precondition hole (diesel may
increase contamination of site if
hydrocarbons are a concern).
Bentonite
Pellets Granular bentonite compressed into a Uniform in size. Easy to use. Must be hydrated after placement.
tablet Produces a low permeability seal. Shrinkage may occur when desiccated
or when in contact with high
concentrations of organic compounds
(greater than 2 %) or materials that
are strongly acidic or alkaline.
Expensive.
Pellets Granular bentonite compressed into a Uniform in size. Easy to use. Must be hydrated after placement.
tablet Produces a low permeability seal. Shrinkage may occur when desiccated
or when in contact with high
concentrations of organic compounds
(greater than 2 percent) or materials
that are strongly acidic or alkaline.
Expensive.
D5299/D5299M − 18
TABLE 1 Continued
Chips Raw mined montmorillonite in the form Inexpensive. No mixing equipment Difficult to place. Must be hydrated
1 3
of chunks .60 to 2 cm [ ⁄4 to ⁄4 in.] in needed. Forms a low-permeability after placement. Less swelling than
size. seal. beneficiated bentonite. Shrinkage may
occur when desiccated when in
contact with high concentrations of
organic compounds (greater than 2 %)
or materials that are strongly acidic or
alkaline.
Chips Raw mined montmorillonite in the form Inexpensive. No mixing equipment Difficult to place. Must be hydrated
1 3
of chunks 0.60 to 2 cm [ ⁄4 to ⁄4 in.] in needed. Forms a low-permeability after placement. Less swelling than
size. seal. beneficiated bentonite. Shrinkage may
occur when desiccated when in
contact with high concentrations of
organic compounds (greater than 2
percent) or materials that are strongly
acidic or alkaline.
Granular Raw mined montmorillonite crushed Can be placed at depth in dry holes. Difficult to place in holes containing
and seared to a #8 to #20-mesh size. Forms a low-permeability seal. water as it quickly hydrates. Can
0.841 to 2.38 mm [.331 to .0937 in.] bridge in hole. May desiccate when in
contact with high concentrations of
organic compounds (greater than 2 %)
or materials that are strongly acidic or
alkaline causing shrinkage.
Granular Raw mined montmorillonite crushed Can be placed at depth in dry holes. Difficult to place in holes containing
and seared to a #8 to #20-mesh size. Forms a low-permeability seal. water as it quickly hydrates. Can
0.841 to 2.38 mm [0.331 to 0.0937 in.] bridge in hole. May desiccate when in
contact with high concentrations of
organic compounds (greater than 2
percent) or materials that are strongly
acidic or alkaline causing shrinkage.
Powdered Pulverized and seared bentonite that Used with cement to compensate for May not be a desirable plugging
passes a #200- mesh .074 mm [.0029 shrinkage (under saturated material in deep vadose zones due to
in.] screen. Used as drilling mud or as conditions). Other additives can be the drying out of the material, resulting
an additive to cement. used to inhibit swelling. Retards in cracking. Difficult to place in holes
cement set; lowers heat of hydration. containing water, as it quickly
hydrates. Can bridge in hole. May
desiccate when in contact with high
concentrations of organic compounds
(greater than 2 %) or materials that
are strongly acidic or alkaline causing
shrinkage.
Powdered Pulverized and seared bentonite that Used with cement to compensate for May not be a desirable plugging
passes a #200- mesh 0.074 mm shrinkage (under saturated material in deep vadose zones due to
[0.0029 in.] screen. Used as drilling conditions). Other additives can be the drying out of the material, resulting
mud or as an additive to cement. used to inhibit swelling. Retards in cracking. Difficult to place in holes
cement set; lowers heat of hydration. containing water, as it quickly
hydrates. Can bridge in hole. May
desiccate when in contact with high
concentrations of organic compounds
(greater than 2 percent) or materials
that are strongly acidic or alkaline
causing shrinkage.
High solids clay grout Powdered bentonite (#200 mesh) .074 Does not shrink during curing. Low May not be a desirable plugging
mm [.0029 in.] mixed with fresh water density reduces formation losses. material in deep vadose zones due to
to form a slurry with 20 % solids or Forms a low- permeability seal that the drying out of the material, resulting
more and a density of 1126 Kg/m g/L stays flexible as long as it is hydrated. in cracking. May desiccate when in
[9.4 lb/gal]. contact with high concentrations of
This would be approximately 0.9 kg [2 organic compounds (greater than 2 %)
lb] of bentonite for each 3.8 L [gal] of or materials that are strongly acidic or
water. alkaline causing shrinkage. A low-
strength material subject to expansion
under low-pressure differentials such
as artesian conditions.
High solids clay grout Powdered bentonite (#200 mesh) Does not shrink during curing. Low May not be a desirable plugging
0.074 mm [0.0029 in.] mixed with density reduces formation losses. material in deep vadose zones due to
fresh water to form a slurry with Forms a low-permeability seal that the drying out of the material, resulting
20 percent solids or more and a stays flexible as long as it is hydrated. in cracking. May desiccate when in
density of 1126 Kg/m g/L [9.4 lb/gal]. contact with high concentrations of
This would be approximately 0.9 kg [2 organic compounds (greater than
lb] of bentonite for each 3.8 L [gal] of 2 percent) or materials that are
water. strongly acidic or alkaline causing
shrinkage. A low-strength material
subject to expansion under low-
pressure differentials such as artesian
conditions.
Low solids grouts Less than 20 % solids Easily placed and flowable Excessive shrinkage initially and over
time may lead to inadequate plugging.
D5299/D5299M − 18
TABLE 1 Continued
Low solids grouts Less than 20 percent solids Easily placed and flowable Excessive shrinkage initially and over
time may lead to inadequate plugging.
6.5.5 Type V—Type V cement has high resistance to sulfate, and brine solutions. This material has ultimate strength
development somewhat less than either Types I or II.
6.5.6 Type K cement is expansive and can be used to compensate for shrinkage. This cement is basically Type I or more
commonly Type II Portland Cement with additives to produce expansion. It can be of use in plugging situations where
water-tightness is important. Type K cement contains calciu
...