ASTM D6517-18(2023)

Standard Guide for Field Preservation of Ground Water Samples

SIGNIFICANCE AND USE
4.1 Ground water samples are subject to chemical, physical, and biological change relative to in- situ conditions at the ground surfaces as a result of exposure to ambient conditions during sample collection (for example, pressure, temperature, ultraviolet radiation, atmospheric oxygen, and contaminants) (1) (2).6 Physical and chemical preservation of samples minimize further changes in sample chemistry that can occur from the moment the ground water sample is retrieved, to the time it is removed from the sample container for extraction or analysis, or both. Measures also should be taken to preserve the physical integrity of the sample container.  
4.2 The need for sample preservation for specific analytes should be defined prior to the sampling event and documented in the site-specific sampling and analysis plan in accordance with Guide D5903. The decision to preserve a sample should be made on a parameter-specific basis as defined by individual analytical methods.  
4.3 This guide includes examples from government documents in the United States. When work is in other countries or regions, the local governing or regulating agencies should be consulted.  
Note 1: 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 Practice 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.
SCOPE
1.1 This guide covers methods for field preservation of ground water samples from the point of sampling through receipt at the laboratory. Laboratory preservation methods are not described in this guide. Purging and sampling techniques are not addressed in this standard but are addressed in Guides D6564/D6564M, D6634/D6634M, D7929, and Practice D6771.  
1.2 Ground water samples are subject to chemical, physical, and biological change relative to in situ conditions at the ground surfaces due to exposure to ambient conditions during sample collection. Physical and chemical preservation of samples minimize further changes in sample chemistry that can occur from the moment the ground water sample is retrieved, to the time it is removed from the sample container for extraction or analysis.  
1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 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.  
1.5 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.  
1.6 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 ...

General Information

• Status: Published
• Publication Date: 31-Oct-2023
• ICS: 13.060.10 - Water of natural resources
• Technical Committee: D18 - Soil and Rock
• Drafting Committee: D18.21 - Groundwater and Vadose Zone Investigations

Relations

• Replaces: ASTM D6517-18 - Standard Guide for Field Preservation of Ground Water Samples
• Effective Date: 01-Nov-2023
• Refers: ASTM D3694-96(2024) - Standard Practices for Preparation of Sample Containers and for Preservation of Organic Constituents
• Effective Date: 01-Apr-2024
• Refers: ASTM D6564/D6564M-17(2024) - Standard Guide for Field Filtration of Groundwater Samples
• Effective Date: 01-Feb-2024
• Refers: ASTM D6089-19(2023) - Standard Guide for Documenting a Groundwater Sampling Event
• Effective Date: 01-Nov-2023
• 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 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 D6089-19 - Standard Guide for Documenting a Groundwater Sampling Event
• Effective Date: 01-Aug-2019
• Refers: ASTM D6564/D6564M-17 - Standard Guide for Field Filtration of Groundwater Samples
• Effective Date: 15-Dec-2017
• Refers: ASTM D3694-96(2017) - Standard Practices for Preparation of Sample Containers and for Preservation of Organic Constituents
• Effective Date: 15-Dec-2017
• Referred By: ASTM D6001/D6001M-20 - Standard Guide for Direct-Push Groundwater Sampling for Environmental Site Characterization
• Effective Date: 01-Nov-2023
• Referred By: ASTM D6771-21 - Standard Practice for Low-Flow Purging and Sampling Used for Groundwater Monitoring
• Effective Date: 01-Nov-2023
• Referred By: ASTM D7929-20 - Standard Guide for Selection of Passive Techniques for Sampling Groundwater Monitoring Wells
• Effective Date: 01-Nov-2023
• Referred By: ASTM D7069-04(2015) - Standard Guide for Field Quality Assurance in a Groundwater Sampling Event
• Effective Date: 01-Nov-2023
• Referred By: ASTM D4448-01(2019) - Standard Guide for Sampling Ground-Water Monitoring Wells
• Effective Date: 01-Nov-2023
• Referred By: ASTM D6699-16 - Standard Practice for Sampling Liquids Using Bailers
• Effective Date: 01-Nov-2023

Overview

ASTM D6517-18(2023), Standard Guide for Field Preservation of Ground Water Samples issued by ASTM International, provides comprehensive guidelines for the effective field preservation of groundwater samples. Preserving groundwater samples from the moment of collection through to laboratory receipt is essential to ensure sample integrity and reliable analytical data. This guide focuses on methods for physical and chemical preservation, the selection and handling of sample containers, and documentation procedures to minimize changes in sample chemistry due to exposure to ambient conditions. Proper adherence reduces the risk of contamination, chemical alteration, and loss of analyte, ensuring sample results accurately reflect in situ groundwater conditions.

Key Topics

• Scope and Application
  • Covers methods for field preservation, not laboratory preservation.
  • Excludes detailed purging and sampling techniques, which are addressed in other ASTM guides.
• Risks to Sample Integrity
  • Groundwater samples are vulnerable to chemical, physical, and biological changes after collection.
  • Exposure to temperature fluctuations, ultraviolet light, oxygen, and contaminants can compromise sample quality.
• Preservation Methods
  • Physical Preservation: Includes temperature control and careful packaging to prevent container breakage and cross-contamination.
  • Chemical Preservation: Addition of specific chemicals (e.g., acids, bases, or biocides) to inhibit reactions, maintain pH, or prevent microbial activity.
• Sample Containers
  • Selection based on analyte requirements, container material (e.g., glass, polyethylene), and regulatory guidelines.
  • Containers should be appropriately cleaned, sealed, and protected.
• Documentation and Traceability
  • Detailed record-keeping of preservation methods, sample handling, container type, temperatures, and chain-of-custody procedures.

Applications

Adopting ASTM D6517-18 promotes best practices in a variety of environmental and engineering projects, such as:

• Environmental Site Assessments: Ensuring the accuracy of groundwater monitoring during site investigations or remediation projects.
• Compliance Monitoring: Supporting regulatory compliance with national and local water quality standards for drinking water, environmental discharge, and hazardous waste.
• Research and Laboratory Analysis: Providing consistent methods for sample preservation in academic and industrial research projects.
• Field Sampling Operations: Serving as a training reference for environmental sampling technicians, consultants, and laboratories involved in groundwater assessment.

Implementing these preservation techniques is particularly crucial where decisions regarding public health, regulatory compliance, or environmental remediation are based on groundwater monitoring data.

Related Standards

ASTM D6517-18 references and complements other key standards and guidance documents for groundwater sampling and analysis:

• ASTM D5903 - Planning and preparing for a groundwater sampling event.
• ASTM D3694 - Preparation of sample containers and preservation of organic constituents.
• ASTM D4840 - Sample chain-of-custody procedures.
• ASTM D6564/D6564M - Field filtration of groundwater samples.
• ASTM D6771 - Low-flow purging and sampling for groundwater monitoring.
• Standard Methods for the Examination of Water and Wastewater - Additional best practices for water sample handling.
• Relevant U.S. EPA and international regulatory guidelines - Referenced for parameter-specific preservation and transport requirements.

By integrating ASTM D6517-18 with these related documents, organizations can establish robust groundwater sampling programs that assure data quality, comparability, and defensibility. This standard is especially valuable for environmental professionals seeking to meet regulatory obligations and ensure high-quality groundwater data.

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: D6517 − 18 (Reapproved 2023)
Standard Guide for
Field Preservation of Ground Water Samples
This standard is issued under the fixed designation D6517; 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* 1.6 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This guide covers methods for field preservation of
ization established in the Decision on Principles for the
ground water samples from the point of sampling through
Development of International Standards, Guides and Recom-
receipt at the laboratory. Laboratory preservation methods are
mendations issued by the World Trade Organization Technical
not described in this guide. Purging and sampling techniques
Barriers to Trade (TBT) Committee.
are not addressed in this standard but are addressed in Guides
D6564/D6564M, D6634/D6634M, D7929, and Practice
D6771. 2. Referenced Documents
1.2 Ground water samples are subject to chemical, physical,
2.1 ASTM Standards:
and biological change relative to in situ conditions at the
D653 Terminology Relating to Soil, Rock, and Contained
ground surfaces due to exposure to ambient conditions during
Fluids
sample collection. Physical and chemical preservation of
D3694 Practices for Preparation of Sample Containers and
samples minimize further changes in sample chemistry that can
for Preservation of Organic Constituents
occur from the moment the ground water sample is retrieved,
D3740 Practice for Minimum Requirements for Agencies
to the time it is removed from the sample container for
Engaged in Testing and/or Inspection of Soil and Rock as
extraction or analysis.
Used in Engineering Design and Construction
1.3 Units—The values stated in SI units are to be regarded
D4840 Guide for Sample Chain-of-Custody Procedures
as standard. No other units of measurement are included in this
D5903 Guide for Planning and Preparing for a Groundwater
standard.
Sampling Event
1.4 This guide offers an organized collection of information D6089 Guide for Documenting a Groundwater Sampling
or a series of options and does not recommend a specific Event
course of action. This document cannot replace education or
D6564/D6564M Guide for Field Filtration of Groundwater
experience and should be used in conjunction with professional
Samples
judgment. Not all aspects of this guide may be applicable in all
D6634/D6634M Guide for Selection of Purging and Sam-
circumstances. This ASTM standard is not intended to repre-
pling Devices for Groundwater Monitoring Wells (With-
sent or replace the standard of care by which the adequacy of
drawn 2023)
a given professional service must be judged, nor should this
D6771 Practice for Low-Flow Purging and Sampling Used
document be applied without consideration of a project’s many
for Groundwater Monitoring
unique aspects. The word“ Standard” in the title of this
D7929 Guide for Selection of Passive Techniques for Sam-
document means only that the document has been approved
pling Groundwater Monitoring Wells
through the ASTM consensus process.
2.2 Other Documents:
1.5 This standard does not purport to address all of the
Standard Methods for the Examination of Water and
safety concerns, if any, associated with its use. It is the
Wastewater, 20th ed., 1999
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock Standards volume information, refer to the standard’s Document Summary page on
and is the direct responsibility of Subcommittee D18.21 on Groundwater and the ASTM website.
Vadose Zone Investigations The last approved version of this historical standard is referenced on
Current edition approved Nov. 1, 2023. Published November 2023. Originally www.astm.org.
approved in 2000. Last previous edition approved in 2018 as D6517 – 18. DOI: Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
10.1520/D6517-18R23. 4th Floor, New York, NY 10036, http://www.ansi.org.
*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
D6517 − 18 (2023)
International Air Transport Association Dangerous Goods (1) (2). Physical and chemical preservation of samples mini-
Regulations mize further changes in sample chemistry that can occur from
U.S. EPA, Office of Solid Waste, SW-846, 3rd ed. (with the moment the ground water sample is retrieved, to the time it
updates) is removed from the sample container for extraction or
U.S. EPA, Title 40, Code of Federal Regulations, Part 136 analysis, or both. Measures also should be taken to preserve the
with updates physical integrity of the sample container.
U.S. DOT, Title 49, Code of Federal Regulations, Part 172
4.2 The need for sample preservation for specific analytes
with updates
should be defined prior to the sampling event and documented
in the site-specific sampling and analysis plan in accordance
3. Terminology
with Guide D5903. The decision to preserve a sample should
be made on a parameter-specific basis as defined by individual
3.1 Definitions—For definitions of common technical terms
in this standard, refer to Terminology D653. analytical methods.
4.3 This guide includes examples from government docu-
3.2 Definitions of Terms Specific to This Standard:
ments in the United States. When work is in other countries or
3.2.1 chemical preservation, n—in ground water sampling,
regions, the local governing or regulating agencies should be
the addition of acidic, alkaline or biologically toxic
consulted.
compounds, or combination thereof, to a ground water sample
to prevent changes in chemical properties of the sample that
NOTE 1—The quality of the result produced by this standard is
may occur after collection.
dependent on the competence of the personnel performing it, and the
suitability of the equipment and facilities used. Agencies that meet the
3.2.2 holding time, n—in ground water sampling, the maxi-
criteria of Practice D3740 are generally considered capable of competent
mum amount of time that may transpire from the moment a
and objective testing/sampling/inspection/etc. Users of this standard are
sample container is filled to the time the sample is extracted or
cautioned that compliance with Practice D3740 does not in itself assure
analyzed. Holding times are parameter-specific, variable in reliable results. Reliable results depend on many factors; Practice D3740
provides a means of evaluating some of those factors.
length, and defined by laboratory analytical methods.
3.2.3 temperature blank, n—in ground water sampling, a
5. Timing and Purpose of Ground Water Sample
quality control sample that is transported with samples and is
Preservation
used by the laboratory performing sample analyses to verify
5.1 Ground water samples should be preserved in the field at
that temperature-sensitive samples have been adequately
the time of sample collection using physical means to prevent
cooled for shipment to and arrival at the laboratory.
sample container breakage or temperature increases, and
3.2.3.1 Discussion—Forms of temperature blank include:
chemical means to minimize changes in ground water sample
(1) using a commercially prepared, fluid-filled bottle contain-
chemistry prior to laboratory analysis.
ing a permanently fixed, calibrated, and certified thermometer,
the temperature of which is read directly by the laboratory; (2)
6. Ground Water Sample Preservation Procedures
submission of a designated sample container filled with water
6.1 Ground water sample preservation procedures are
(for example, ground water, distilled water, or deionized water)
grouped into two general categories: (1) physical preservation
that is opened by the laboratory and immediately measured for
and (2) chemical preservation. Preservation procedures should
temperature of the water using a calibrated and certified
address the following details on a parameter-specific basis:
thermometer; or (3) submission of a designated container filled
sample container design and construction, protection from
with water (for example, ground water, distilled water, or
ultraviolet light, temperature control, chemical addition, and
deionized water) on which the laboratory uses a remote
pH control measures (2).
infrared temperature sensor to measure the temperature. Re-
6.1.1 Physical Preservation of Ground Water Samples—
gardless of the method used, the measured temperatures are
Physical ground water sample preservation methods include:
compared against the required temperature for each sample in
(1) use of appropriate sample collection containers for each
conjunction with a previously defined window of acceptable
parameter being analyzed, (2) use of appropriate packing of
variance from this required temperature as documented in the
sample containers for shipment to prevent sample container
sampling and analysis plan.
breakage and potential cross-contamination of samples during
shipment, and (3) temperature control.
4. Significance and Use
6.1.1.1 Sample Container Selection—Proper selection of
4.1 Ground water samples are subject to chemical, physical,
containers for ground water sample collection is an important
and biological change relative to in- situ conditions at the
means of protecting the integrity of the sample. Specifications
ground surfaces as a result of exposure to ambient conditions
on container design, including shape, volume, gas tightness,
during sample collection (for example, pressure, temperature,
materials of construction, and use of cap liners, are defined for
ultraviolet radiation, atmospheric oxygen, and contaminants)
specific parameters or suites of parameters (for example, amber
glass containers protect photosensitive analytes such as (PCBs)
Available from U.S. Government Printing Office Superintendent of Documents,
732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:// The boldface numbers in parentheses refer to the list of references at the end of
www.access.gpo.gov. this standard.
D6517 − 18 (2023)
from chemical alteration). Specifications for sample container documents. Chemicals can be used to adjust sample pH or
selection are documented in parameter-specific analytical inhibit microbial activity to prevent chemical alteration of
methods (for example, ASTM, U.S. EPA SW846, AWWA samples. Initial pH of samples should be determined prior to
Standard Methods) as well as in state and local regulatory chemical preservation so appropriate chemical adjustment can
guidelines on ground water sample collection and preservation. be made.
The type of sample containers to be used in a sampling event 6.1.2.3 Ground water samples can be chemically preserved
should be determined during sampling event planning in
in one of several ways: (1) titration of pH-adjusting compounds
accordance with Guide D5903 and documented in the sampling (for example, nitric acid) while monitoring pH change with a
and analysis plan as described in 8.1 of this guide and Guide
pH meter capable of measuring to .1 pH units (2) addition of a
D6089. premeasured volume of liquid preservative (for example,
6.1.1.2 Sample Container Packing and Shipping—Field per-
sulfuric acid) contained in glass vials or ampules to the sample
sonnel should package and ship samples in compliance with container (Note 3); (3) addition of pelletized preservative (for
applicable regional and national regulations. Sample containers
example, sodium hydroxide) to the sample container; and (4)
should be shipped in a manner that will make sure the samples addition of preservative to empty sample containers prior to
are received intact by the laboratory, at the appropriate shipment of the empty containers to the field (that is, prepre-
temperature, and as soon as practicable to allow sufficient time served sample containers) Note 4. After the sample container is
for the laboratory to perform the requested analyses within the filled and preserved, it should b
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