1、Designation: D6517 00 (Reapproved 2012)1Standard Guide forField Preservation of Groundwater Samples1This standard is issued under the fixed designation D6517; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEEditorial changes were made throughout in May 2012.1. Scope1.1 This guide covers methods for field preservation ofgroundwater samples. La
3、boratory preservation methods are notdescribed in this guide.1.2 This standard may involve hazardous materials,operations, 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 toestab
4、lish appropriate safety and health practices and deter-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 orexperien
5、ce and should be used in conjunction with professionaljudgment. 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 thisdo
6、cument be applied without consideration of a projects 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:2D653 Terminology Relating to Soil, Rock, and Containe
7、dFluidsD3694 Practices for Preparation of Sample Containers andfor Preservation of Organic ConstituentsD5903 Guide for Planning and Preparing for a GroundwaterSampling EventD6089 Guide for Documenting a Ground-Water SamplingEvent2.2 Other Documents:Standard Methods for the Examination of Water andWa
8、stewater, 20th ed., 19993International Air Transport Association Dangerous GoodsRegulations4U.S. EPA, Office of Solid Waste, SW-846, 3rd ed.U.S. EPA, Title 40, Code of Federal Regulations, Part 136U.S. DOT, Title 49, Code of Federal Regulations, Part 1723. Terminology3.1 Definitions: For definitions
9、 of common technical termsin this standard, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 chemical preservationthe addition of acidic, alkalineor biologically toxic compounds, or combination thereof, to agroundwater sample to prevent changes in chemical propertie
10、sof the sample that may occur after collection.3.2.2 holding timethe maximum amount of time that maytranspire from the moment a sample container is filled to thetime the sample is extracted or analyzed. Holding times areparameter-specific, variable in length, and defined by labora-tory analytical me
11、thods.3.2.3 physical preservationmethods that are implementedto protect the physical integrity of a groundwater sample fromthe time the sample is collected until the sample is analyzed.3.2.4 temperature blanka quality control sample that istransported with samples and is used by the laboratory per-f
12、orming 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) using a commerciallyprepared, fluid-filled bottle containing a permanently fixed NationalInstit
13、ute 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 water (forexample, groundwater, distilled water, or deionized water) that is openedby the laboratory
14、 and immediately measured for temperature of the water1This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone InvestigationsCurrent edition approved May 15, 2012. Published December 2012. Origina
15、llyapproved in 2000. Last previous edition approved in 2005 as D6517 00(2005).DOI: 10.1520/D6517-00R12E1.2For 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 standar
16、ds Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.4Available from the Superintendent of Documents, US Government PrintingOffice, Washington, DC 20402.Copyright ASTM International, 100 Barr Harbor Dri
17、ve, PO Box C700, West Conshohocken, PA 19428-2959. United States1using a National Institute of Standards and Technology-certified (orNIST-traceable) thermometer; or (3) submission of a designated containerfilled with water (for example, groundwater, distilled water, or deionizedwater) on which the l
18、aboratory uses a remote infrared temperature sensorto measure the temperature. Regardless of the method used, all measuredtemperatures are compared against the required temperature for eachsample (for example, 4C) in conjunction with a previously definedwindow of acceptable variance from this requir
19、ed temperature as docu-mented in the sampling and analysis plan.4. Significance and Use4.1 Groundwater samples are subject to chemical, physical,and biological change relative to in- situ conditions at theground surfaces as a result of exposure to ambient conditionsduring sample collection (for exam
20、ple, 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 groundwater sample is retrieved, to the time itis removed from the sample conta
21、iner 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 event and documentedin the site-specific sampling and analysis plan in acco
22、rdancewith Guide D5903. The decision to preserve a sample shouldbe made on a parameter-specific basis as defined by individualanalytical methods.5. Timing and Purpose of Groundwater SamplePreservation5.1 Groundwater samples should be preserved in the field atthe time of sample collection using physi
23、cal means to preventsample container breakage or temperature increases, andchemical means to minimize changes in groundwater samplechemistry prior to laboratory analysis.6. Groundwater Sample Preservation Procedures6.1 Groundwater sample preservation procedures aregrouped into two general categories
24、: (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, temperature control, chemical addition, andpH control measures (2).6.1.1 Phy
25、sical Preservation of Groundwater SamplesPhysical groundwater sample preservation methods include:(1) use of appropriate sample collection containers for eachparameter being analyzed, (2) use of appropriate packing ofsample containers for shipment to prevent sample containerbreakage and potential cr
26、oss-contamination of samples duringshipment, and (3) temperature control.6.1.1.1 Sample Container Selection Proper selection ofcontainers for groundwater sample collection is an importantmeans of protecting the integrity of the sample. Specificationson container design, including shape, volume, gas
27、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 alteration). Specifications for sample containerselection are documented in parameter
28、-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 groundwater samplecollection and preservation. The type of sample containers tobe used in a sampling event should be determined duri
29、ngsampling event planning in accordance with Guide D5903 anddocumented in the sampling and analysis plan as described in8.1 of this guide and Guide D6089.6.1.1.2 Sample Container Packing and ShippingField per-sonnel should package and ship samples in compliance with allapplicable regulations includi
30、ng the Department of Transpor-tation (for example, Title 49 Code of Federal Regulations, Part172) and the International Air Transportation Association(IATA). Sample containers should be shipped in a manner thatwill ensure the samples are received intact by the laboratory, atthe appropriate temperatu
31、re, 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 Temperature ControlSamples analyzed for someparameters (for example, nitrite) require tempe
32、rature 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 should be lowered as soon aspossible and maintained at 4C until the sample is anal
33、yzed.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 ice may be used to coolsamples, however, care should be taken to prevent samplefree
34、zing. Reuseable ice packs may be used to lower sampletemperature, however, they often do not have the capacity toadequately lower or maintain temperatures, or both;consequently, their use is not recommended (4). A temperatureblank should be used with each shipping container of samplesto determine ac
35、tual sample temperatures at the time the sampleshipment is received by the laboratory.6.1.2 Chemical Preservation of Groundwater Samples:6.1.2.1 Chemical preservation of groundwater samples in-volves the addition of one or more chemicals (reagent-grade orbetter) on a parameter-specific basis to prot
36、ect 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 guidancedocuments. Chemicals can be used to adjust sample pH orinhibit microbial activi
37、ty 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 Groundwater samples can be chemically preservedin one of several ways: (1) titration of pH-adjusting compounds5The boldface numb
38、ers in parentheses refer to the list of references at the end ofthis standard.D6517 00 (2012)12(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
39、vials or ampules to the samplecontainer (Note 2); (3) addition of pelletized preservative (forexample, sodium hydroxide) to the sample container; and (4)addition of preservative to empty sample containers prior toshipment of the empty containers to the field (that is, prepre-served sample containers
40、) 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 taken not to add too large a volume ofchemical preservative to prevent sample dilution.
41、 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 the sample.6.1.2.4 The end point of chemical preservation, designed toadjust pH to spe
42、cific 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 separatecontainer or a parallel sample can be collected for pH verifi-cation(for example, for
43、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 notto prerinse the container with the sample and to avoidoverfilling the container to
44、prevent loss of chemical preserva-tive.NOTE 5Samples containing a light non-aqueous phase should not bechemically preserved with strong acid or base.6.1.2.5 When using premeasured volume preservatives suchas vials, ampules, or prepreserved containers, additional pre-servative should be provided by t
45、he laboratory and be availablein 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 6, Note 7, and Note 8).7. Timing of Groundwater Sample Preserv
46、ation7.1 Groundwater samples 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 6When using ampules,
47、care should be taken to avoid introduc-ing glass shards or painted ampule surfaces into the sample containerwhich could impact sample integrity (5).NOTE 7Even when following recommended chemical preservationmethods, chemical reactions may occur (2). For example, water contain-ing high concentrations
48、 of calcium carbonate may 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,
49、and allowed by thesampling and analysis plan.NOTE 8It 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.8. Report8.1 Records should be kept for all forms of sample preser-vation used for groundwater samples. Report the following inaccordance with Guide D6089:8.1.1 Type of sample container(s) used for each parameterbeing analyzed (volume, mat
