1、Designation: D 6517 00 (Reapproved 2005)Standard Guide forField Preservation of Ground-Water Samples1This standard is issued under the fixed designation D 6517; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers methods for field preservation ofground-water samples. Laboratory preservation methods arenot described in th
3、is guide.1.2 This standard may involve hazardous materials, opera-tions, and equipment. This standard does not purport toaddress all of the safety concerns, if any, associated with itsuse. It is the responsibility of the user of this standard toestablish appropriate safety and health practices and d
4、eter-mine the applicability of regulatory limitations prior to use.1.3 This guide offers an organized collection of informationor a series of options and does not recommend a specificcourse of action. This document cannot replace education orexperience and should be used in conjunction with professi
5、onaljudgment. Not all aspects of this guide may be applicable in allcircumstances. This ASTM standard is not intended to repre-sent or replace the standard of care by which the adequacy ofa given professional service must be judged, nor should thisdocument be applied without consideration of a proje
6、cts manyunique aspects. The word“ Standard” in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D 3694 Practices for Preparation of Sample Containers andfor Preservation of Organic ConstituentsD 5903
7、 Guide for Planning and Preparing for a Groundwa-ter Sampling EventD 6089 Guide for Documenting a Ground-Water SamplingEvent2.2 Other Documents:Standard Methods for the Examination of Water andWastewater, 20th ed., 19993International Air Transport Association Dangerous GoodsRegulations4U.S. EPA, Off
8、ice of Solid Waste, SW-846, 3rd ed.U.S. EPA, Title 40, Code of Federal Regulations, Part 136U.S. EPA, Title 49, Code of Federal Regulations, Part 1723. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 chemical preservationthe addition of acidic, alka-line or biologically toxic com
9、pounds, or combination thereof,to a ground-water sample to prevent changes in chemicalproperties of the sample that may occur after collection.3.1.2 holding timethe maximum amount of time that maytranspire from the moment a sample container is filled to thetime the sample is extracted or analyzed. H
10、olding times areparameter-specific, variable in length, and defined by labora-tory analytical methods.3.1.3 physical preservationmethods that are implementedto protect the physical integrity of a ground-water sample fromthe time the sample is collected until the sample is analyzed.3.1.4 temperature
11、blanka quality control sample that istransported with samples and is used by the laboratory per-forming sample analyses to verify that temperature-sensitivesamples have been adequately cooled to 4C for shipment toand arrival at the laboratory (see Note 1).NOTE 1Forms of temperature blank include: (1
12、) using a commerciallyprepared, fluid-filled bottle containing a permanently fixed NationalInstitute of Standards and Technology(NIST)-certified (or NIST-traceable)thermometer, the temperature of which is read directly by the laboratory;(2) submission of a designated sample container filled with wat
13、er (forexample, ground water, distilled water, or deionized water) that is openedby the laboratory and immediately measured for temperature of the waterusing a National Institute of Standards and Technology-certified (orNIST-traceable) thermometer; or (3) submission of a designated containerfilled w
14、ith water (for example, ground water, distilled water, or deionizedwater) on which the laboratory uses a remote infrared temperature sensorto measure the temperature. Regardless of the method used, all measuredtemperatures are compared against the required temperature for each1This guide is under th
15、e jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current edition approved Nov. 1, 2005. Published December 2005. Originallyapproved in 2000. Last previous edition approved in 2000 as D 6517 00.2F
16、or referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 2
17、5 W. 43rd St.,4th Floor, New York, NY 10036.4Available from the Superintendent of Documents, US Government PrintingOffice, Washington, DC 20402.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.sample (for example, 4C) in conjunction w
18、ith a previously definedwindow of acceptable variance from this required temperature as docu-mented in the sampling and analysis plan.4. Significance and Use4.1 Ground-water samples are subject to chemical, physical,and biological change relative to in- situ conditions at theground surfaces as a res
19、ult of exposure to ambient conditionsduring sample collection (for example, pressure, temperature,ultraviolet radiation, atmospheric oxygen, and contaminants)(1)(2).5Physical and chemical preservation of samples mini-mize further changes in sample chemistry that can occur fromthe moment the ground-w
20、ater sample is retrieved, to the time itis removed from the sample container for extraction oranalysis, or both. Measures also must be taken to preserve thephysical integrity of the sample container.4.2 The need for sample preservation for specific analytesshould be defined prior to the sampling eve
21、nt and documentedin the site-specific sampling and analysis plan in accordancewith Guide D 5903. The decision to preserve a sample shouldbe made on a parameter-specific basis as defined by individualanalytical methods.5. Timing and Purpose of Ground-Water SamplePreservation5.1 Ground-water samples s
22、hould be preserved in the fieldat the time of sample collection using physical means toprevent sample container breakage or temperature increases,and chemical means to minimize changes in ground-watersample chemistry prior to laboratory analysis.6. Ground-Water Sample Preservation Procedures6.1 Grou
23、nd-water sample preservation procedures aregrouped into two general categories: (1) physical preservationand (2) chemical preservation. Preservation procedures shouldaddress the following details on a parameter-specific basis:sample container design and construction, protection fromultraviolet light
24、, temperature control, chemical addition, andpH control measures (2).6.1.1 Physical Preservation of Ground-Water SamplesPhysical ground-water sample preservation methods include:(1) use of appropriate sample collection containers for eachparameter being analyzed, (2) use of appropriate packing ofsam
25、ple containers for shipment to prevent sample containerbreakage and potential cross-contamination of samples duringshipment, and (3) temperature control.6.1.1.1 Sample Container SelectionProper selection ofcontainers for ground-water sample collection is an importantmeans of protecting the integrity
26、 of the sample. Specificationson container design, including shape, volume, gas tightness,materials of construction, and use of cap liners, are defined forspecific parameters or suites of parameters (for example, amberglass containers protect photosensitive analytes such as (PCBs)from chemical alter
27、ation). Specifications for sample containerselection are documented in parameter-specific analyticalmethods (for example, ASTM, U.S. EPA SW846, AWWAStandard Methods) as well as in Federal (40 CFR Part 136),state, and local regulatory guidelines on ground-water samplecollection and preservation. The
28、type of sample containers tobe used in a sampling event should be determined duringsampling event planning in accordance with Guide D 5903 anddocumented in the sampling and analysis plan as described in8.1 of this guide and Guide D 6089.6.1.1.2 Sample Container Packing and ShippingFieldpersonnel sho
29、uld package and ship samples in compliance withall applicable regulations including the Department of Trans-portation (for example, Title 49 Code of Federal Regulations,Part 172) and the International Air Transportation Association(IATA). Sample containers should be shipped in a manner thatwill ensu
30、re the samples are received intact by the laboratory, atthe appropriate temperature, and as soon as possible to allowsufficient time for the laboratory to perform the requestedanalyses within the holding time defined by the applicablelaboratory analytical method for each parameter.6.1.1.3 Temperatur
31、e ControlSamples analyzed for someparameters (for example, nitrite) require temperature control.The temperature of these samples should be lowered to 4Cimmediately after performing any field analyses required (forexample, temperature or pH) and chemical preservation (3).When necessary, temperature s
32、hould be lowered as soon aspossible and maintained at 4C until the sample is analyzed.Sample temperatures can be lowered most efficiently usingon-site refrigeration or wet ice. Wet ice may need to bereplenished prior to shipping to maintain sample temperaturesat 4C. If required by regulation, dry ic
33、e may be used to coolsamples, however, care should be taken to prevent samplefreezing. Reuseable ice packs may be used to lower sampletemperature, however, they often do not have the capacity toadequately lower or maintain temperatures, or both; conse-quently, their use is not recommended (4).Atempe
34、rature blankshould be used with each shipping container of samples todetermine actual sample temperatures at the time the sampleshipment is received by the laboratory.6.1.2 Chemical Preservation of Ground-Water Samples:6.1.2.1 Chemical preservation of ground-water samples in-volves the addition of o
35、ne or more chemicals (reagent-grade orbetter) on a parameter-specific basis to protect sample integrity.Appendix X1 provides examples of common analyte-specificchemical preservation methods.6.1.2.2 Chemical preservation is specified in numerousanalytical methods as well as in various regulatory guid
36、ancedocuments. Chemicals can be used to adjust sample pH orinhibit microbial activity to prevent chemical alteration ofsamples. Initial pH of samples should be determined prior tochemical preservation so appropriate chemical adjustment canbe made.6.1.2.3 Ground-water samples can be chemically preser
37、vedin one of several ways: (1) titration of pH-adjusting compounds(for example, nitric acid) while monitoring pH change with apH meter or narrow-range litmus paper; (2) addition of apremeasured volume of liquid preservative (for example,sulfuric acid) contained in glass vials or ampules to the sampl
38、econtainer (Note 2); (3) addition of pelletized preservative (for5The boldface numbers in parentheses refer to the list of references at the end ofthis standard.D 6517 00 (2005)2example, sodium hydroxide) to the sample container; and (4)addition of preservative to empty sample containers prior toshi
39、pment of the empty containers to the field (that is, prepre-served sample containers) Note 3.After the sample container isfilled and preserved, it should be securely capped and gentlyinverted to ensure uniform distribution of the preservativethroughout the sample (seeNote 4).NOTE 2Care should be tak
40、en not to add too large a volume ofchemical preservative to prevent sample dilution. A generally acceptedlimit is 0.5 % maximum dilution.NOTE 3The use of prepreserved containers should be evaluated on aparameter-specific basis.NOTE 4Pelletized preservatives may take longer to dissolve and mixwith th
41、e sample.6.1.2.4 The end point of chemical preservation, designed toadjust pH to specific final pH levels, (for example, 12.0) should be verified in the field using narrow-range litmuspaper (pH paper) or a properly calibrated pH meter. A smallamount of sample can either be decanted into a separateco
42、ntainer or a parallel sample can be collected for pH verifi-cation(for example, for samples containing light non-aqueousphases), rather than introducing foreign materials into thesample container being submitted for analysis. When collect-ing samples in prepreserved containers, care must be taken no
43、tto prerinse the container with the sample and to avoidoverfilling the container to prevent loss of chemical preserva-tive.6.1.2.5 When using premeasured volume preservatives suchas vials, ampules, or prepreserved containers, additional pre-servative should be provided by the laboratory and be avail
44、ablein the field to add to a sample if necessary to reach the requiredfinal pH. The additional preservative should be the same type,grade, and concentration as that used initially to preserve thesample (see Note 5, Note 6, and Note 7).7. Timing of Ground-Water Sample Preservation7.1 Ground-water sam
45、ples should be preserved immediatelyupon collection to minimize the time for chemical alteration ofsample chemistry to occur (3). An exception is those samplesrequiring field filtration, which should be field-filtered first,then chemically preserved.NOTE 5When using ampules, care should be taken to
46、avoid introduc-ing glass shards or painted ampule surfaces into the sample containerwhich could impact sample integrity (5).NOTE 6Even when following recommended chemical preservationmethods, chemical reactions may occur (2). For example, water contain-ing high concentrations of calcium carbonate ma
47、y effervesce whenacidified. In these cases, modifications of sample preservation methodsmay be necessary, such as collecting an unpreserved sample or usingalternate chemical preservatives.Any modifications must be pre-approvedby regulatory agencies and laboratories involved, and allowed by thesampli
48、ng and analysis plan.NOTE 7It may be necessary to establish site-specific protocol toaddress acceptable periods for storage and storage conditions for prepre-served sample containers due to the potential for chemical reactions tooccur between the chemical preservative and the empty sample container.
49、8. Report8.1 Records should be kept for all forms of sample preser-vation used for ground-water samples. Report the following inaccordance with Guide D 6089:8.1.1 Type of sample container(s) used for each parameterbeing analyzed (volume, materials of construction, type of cap,and so forth);8.1.2 Number of each type of sample container actuallyfilled;8.1.3 Packaging method(s) used to prevent sample bottlebreakage during sample storage and shipment;8.1.4 Temperature and pH of ground-water samples at thetime of sample collection;8.1.5 How ground-water samples were c
