ASTM D6517-00(2005)
(Guide)Standard Guide for Field Preservation of Groundwater Samples
Standard Guide for Field Preservation of Groundwater Samples
SIGNIFICANCE AND USE
Groundwater 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). Physical and chemical preservation of samples minimize further changes in sample chemistry that can occur from the moment the groundwater sample is retrieved, to the time it is removed from the sample container for extraction or analysis, or both. Measures also must be taken to preserve the physical integrity of the sample container.
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.
SCOPE
1.1 This guide covers methods for field preservation of groundwater samples. Laboratory preservation methods are not described in this guide.
1.2 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.3 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.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D6517 − 00(Reapproved 2005)
Standard Guide for
Field Preservation of Groundwater 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 2.2 Other Documents:
Standard Methods for the Examination of Water and
1.1 This guide covers methods for field preservation of
Wastewater, 20th ed., 1999
groundwatersamples.Laboratorypreservationmethodsarenot
International Air Transport Association Dangerous Goods
described in this guide. 4
Regulations
U.S. EPA, Office of Solid Waste, SW-846, 3rd ed.
1.2 This standard may involve hazardous materials,
U.S. EPA, Title 40, Code of Federal Regulations, Part 136
operations, and equipment. This standard does not purport to
U.S. EPA, Title 49, Code of Federal Regulations, Part 172
address all of the safety concerns, if any, associated with its
use. It is the responsibility of the user of this standard to
3. Terminology
establish appropriate safety and health practices and deter-
3.1 Definitions of Terms Specific to This Standard:
mine the applicability of regulatory limitations prior to use.
3.1.1 chemicalpreservation—theadditionofacidic,alkaline
1.3 This guide offers an organized collection of information
or biologically toxic compounds, or combination thereof, to a
or a series of options and does not recommend a specific
groundwater sample to prevent changes in chemical properties
course of action. This document cannot replace education or
of the sample that may occur after collection.
experienceandshouldbeusedinconjunctionwithprofessional
3.1.2 holding time—the maximum amount of time that may
judgment. Not all aspects of this guide may be applicable in all
transpire from the moment a sample container is filled to the
circumstances. This ASTM standard is not intended to repre-
time the sample is extracted or analyzed. Holding times are
sent or replace the standard of care by which the adequacy of
parameter-specific, variable in length, and defined by labora-
a given professional service must be judged, nor should this
tory analytical methods.
document be applied without consideration of a project’s many
3.1.3 physical preservation—methods that are implemented
unique aspects. The word“ Standard” in the title of this
to protect the physical integrity of a groundwater sample from
document means only that the document has been approved
the time the sample is collected until the sample is analyzed.
through the ASTM consensus process.
3.1.4 temperature blank—a quality control sample that is
transported with samples and is used by the laboratory per-
2. Referenced Documents
forming sample analyses to verify that temperature-sensitive
2.1 ASTM Standards:
samples have been adequately cooled to 4°C for shipment to
D3694 Practices for Preparation of Sample Containers and
and arrival at the laboratory (see Note 1).
for Preservation of Organic Constituents
NOTE1—Formsoftemperatureblankinclude:(1)usingacommercially
D5903 Guide for Planning and Preparing for a Groundwater
prepared, fluid-filled bottle containing a permanently fixed National
Sampling Event
InstituteofStandardsandTechnology(NIST)-certified(orNIST-traceable)
thermometer, the temperature of which is read directly by the laboratory;
D6089 Guide for Documenting a Ground-Water Sampling
(2) submission of a designated sample container filled with water (for
Event
example, groundwater, distilled water, or deionized water) that is opened
by the laboratory and immediately measured for temperature of the water
using a National Institute of Standards and Technology-certified (or
NIST-traceable) thermometer; or (3) submission of a designated container
ThisguideisunderthejurisdictionofASTMCommitteeD18onSoilandRock
filled with water (for example, groundwater, distilled water, or deionized
and is the direct responsibility of Subcommittee D18.21 on Groundwater and
water) on which the laboratory uses a remote infrared temperature sensor
Vadose Zone Investigations
to measure the temperature. Regardless of the method used, all measured
Current edition approved Nov. 1, 2005. Published December 2005. Originally
approved in 2000. Last previous edition approved in 2000 as D6517 – 00. DOI:
10.1520/D6517-00R05.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 4th Floor, New York, NY 10036.
Standards volume information, refer to the standard’s Document Summary page on Available from the Superintendent of Documents, US Government Printing
the ASTM website. Office, Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6517 − 00 (2005)
temperatures are compared against the required temperature for each
selection are documented in parameter-specific analytical
sample (for example, 4°C) in conjunction with a previously defined
methods (for example, ASTM, U.S. EPA SW846, AWWA
window of acceptable variance from this required temperature as docu-
Standard Methods) as well as in Federal (40 CFR Part 136),
mented in the sampling and analysis plan.
state, and local regulatory guidelines on groundwater sample
collection and preservation. The type of sample containers to
4. Significance and Use
be used in a sampling event should be determined during
4.1 Groundwater samples are subject to chemical, physical,
sampling event planning in accordance with Guide D5903 and
and biological change relative to in- situ conditions at the
documented in the sampling and analysis plan as described in
ground surfaces as a result of exposure to ambient conditions
8.1 of this guide and Guide D6089.
during sample collection (for example, pressure, temperature,
6.1.1.2 SampleContainerPackingandShipping—Fieldper-
ultraviolet radiation, atmospheric oxygen, and contaminants)
5 sonnelshouldpackageandshipsamplesincompliancewithall
(1)(2). Physical and chemical preservation of samples mini-
applicable regulations including the Department of Transpor-
mize further changes in sample chemistry that can occur from
tation (for example, Title 49 Code of Federal Regulations, Part
the moment the groundwater sample is retrieved, to the time it
172) and the International Air Transportation Association
is removed from the sample container for extraction or
(IATA). Sample containers should be shipped in a manner that
analysis, or both. Measures also must be taken to preserve the
will ensure the samples are received intact by the laboratory, at
physical integrity of the sample container.
the appropriate temperature, and as soon as possible to allow
4.2 The need for sample preservation for specific analytes
sufficient time for the laboratory to perform the requested
should be defined prior to the sampling event and documented
analyses within the holding time defined by the applicable
in the site-specific sampling and analysis plan in accordance
laboratory analytical method for each parameter.
with Guide D5903. The decision to preserve a sample should
6.1.1.3 Temperature Control—Samples analyzed for some
be made on a parameter-specific basis as defined by individual
parameters (for example, nitrite) require temperature control.
analytical methods.
The temperature of these samples should be lowered to 4°C
immediately after performing any field analyses required (for
5. Timing and Purpose of Groundwater Sample
example, temperature or pH) and chemical preservation (3).
Preservation
When necessary, temperature should be lowered as soon as
5.1 Groundwater samples should be preserved in the field at
possible and maintained at 4°C until the sample is analyzed.
the time of sample collection using physical means to prevent
Sample temperatures can be lowered most efficiently using
sample container breakage or temperature increases, and
on-site refrigeration or wet ice. Wet ice may need to be
chemical means to minimize changes in groundwater sample
replenished prior to shipping to maintain sample temperatures
chemistry prior to laboratory analysis.
at 4°C. If required by regulation, dry ice may be used to cool
samples, however, care should be taken to prevent sample
6. Groundwater Sample Preservation Procedures
freezing. Reuseable ice packs may be used to lower sample
6.1 Groundwater sample preservation procedures are temperature, however, they often do not have the capacity to
grouped into two general categories: (1) physical preservation
adequately lower or maintain temperatures, or both; conse-
and (2) chemical preservation. Preservation procedures should quently, their use is not recommended (4).Atemperature blank
address the following details on a parameter-specific basis:
should be used with each shipping container of samples to
sample container design and construction, protection from determine actual sample temperatures at the time the sample
ultraviolet light, temperature control, chemical addition, and
shipment is received by the laboratory.
pH control measures (2).
6.1.2 Chemical Preservation of Groundwater Samples:
6.1.1 Physical Preservation of Groundwater Samples—
6.1.2.1 Chemical preservation of groundwater samples in-
Physical groundwater sample preservation methods include:
volves the addition of one or more chemicals (reagent-grade or
(1) use of appropriate sample collection containers for each
better)onaparameter-specificbasistoprotectsampleintegrity.
parameter being analyzed, (2) use of appropriate packing of
Appendix X1 provides examples of common analyte-specific
sample containers for shipment to prevent sample container
chemical preservation methods.
breakage and potential cross-contamination of samples during
6.1.2.2 Chemical preservation is specified in numerous
shipment, and (3) temperature control.
analytical methods as well as in various regulatory guidance
6.1.1.1 Sample Container Selection —Proper selection of
documents. Chemicals can be used to adjust sample pH or
containers for groundwater sample collection is an important
inhibit microbial activity to prevent chemical alteration of
means of protecting the integrity of the sample. Specifications
samples. Initial pH of samples should be determined prior to
on container design, including shape, volume, gas tightness,
chemical preservation so appropriate chemical adjustment can
materials of construction, and use of cap liners, are defined for
be made.
specificparametersorsuitesofparameters(forexample,amber
6.1.2.3 Groundwater samples can be chemically preserved
glasscontainersprotectphotosensitiveanalytessuchas(PCBs)
inoneofseveralways:(1)titrationofpH-adjustingcompounds
from chemical alteration). Specifications for sample container
(for example, nitric acid) while monitoring pH change with a
pH meter or narrow-range litmus paper; (2) addition of a
premeasured volume of liquid preservative (for example,
The boldface numbers in parentheses refer to the list of references at the end of
this standard. sulfuric acid) contained in glass vials or ampules to the sample
D6517 − 00 (2005)
by regulatory agencies and laboratories involved, and allowed by the
container (Note 2); (3) addition of pelletized preservative (for
sampling and analysis plan.
example, sodium hydroxide) to the sample container; and (4)
NOTE 7—It may be necessary to establish site-specific protocol to
addition of preservative to empty sample containers prior to
address acceptable periods for storage and storage conditions for prepre-
shipment of the empty containers to the field (that is, prepre-
served sample containers due to the potential for chemical reactions to
servedsamplecontainers)Note3.Afterthesamplecontaineris
occur between the chemical preservative and the empty sample container.
filled and preserved, it should be securely capped and gently
8. Report
inverted to ensure uniform distribution of the preservative
8.1 Records should be kept for all forms of sample preser-
throughout the sample (seeNote 4).
vation used for groundwater samples. Report the following in
NOTE 2—Care should be taken not to add too large a volume of
accordance with Guide D6089:
chemical preservative to prevent sample dilution. A generally accepted
8.1.1 Type of sample container(s) used for each parameter
limit is 0.5 % maximum dilution.
being analyzed (volume, materials of construction, type of cap,
NOTE 3—The use of prepreserved containers should be evaluated on a
and so forth);
parameter-specific basis.
NOTE 4—Pelletized preservatives may take longer to dissolve and mix 8.1.2 Number of each type of sample container actually
with the sample.
filled;
8.1.3 Packaging method(s) used to prevent sample bottle
6.1.2.4 The end point of chemical preservation, designed to
breakage during sample storage and shipment;
adjust pH to specific final pH levels, (for example, <2.0 or
8.1.4 Temperature and pH of groundwater samples at the
>12.0)shouldbeverifiedinthefieldusingnarrow-rangelitmus
time of sample collection;
paper (pH paper) or a properly calibrated pH meter. A small
8.1.5 How groundwater samples were cooled to 4°C, if
amount of sample can either be decanted into a separate
required for physical preservation;
container or a parallel sample can be collected for pH verifi-
8.1.6 Sample temperature at the time of sample shipment;
cation(for example, for samples containing light non-aqueous
8.1.7 Chemical preservative(s) used on a parameter-specific
phases), rather than introducing foreign materials into the
basis:
sample container being submitted for analysis. When collect-
8.1.7.1 What chemicals were added, by whom, time, and
ing samples in prepreserved containers, care must be taken not
date,
to prerinse the container with the sample and to avoid
8.1.7.2 Specifications (if known) on actual preservative(s)
overfilling the container to prevent loss of chemical preserva-
used (that is, source, manufacturer, grade, lot number, and so
tive.
forth),
6.1.2.5 When using premeasured volume preservatives such
8.1.7.3 How the chemical preservative was added,
as vials, ampules, or prepreserved containers, additional pre-
8.1.7.4 Volume of chemical preservative added (if known),
servativeshouldbeprovidedbythelaboratoryandbeavailable
and
in the field to add to a sample if necessary to reach the required
8.1.7.5 Results of field preservation verification tests when
final pH. The additional preservative should be the same type,
pH is adjusted (initial and after preservation).
grade, and concentr
...
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