1、Designation: D6564 00 (Reapproved 2012)1D6564/D6564M 17Standard Guide forField Filtration of Groundwater Samples1This standard is issued under the fixed designation D6564;D6564/D6564M; the number immediately following the designation indicatesthe year of original adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1 NOTEEditorial changes were made throughout in May 2012.1. Scope Scope*1.1 This guide covers methods for field filt
3、ration of groundwater samples collected from groundwater monitoring wells,excluding samples that contain non-aqueous phase liquids (either Dense Non-Aqueous Phase Liquids (DNAPLs) or LightNon-Aqueous Phase Liquids (LNAPLs). Methods of field filtration described herein could also be applied to sample
4、s collectedfrom wells used for other purposes. Laboratory filtration methods are not described in this guide.1.2 This guide provides procedures available for field filtration of groundwater samples. The need for sample filtration forspecific analytes should be defined prior to the sampling event and
5、 documented in the site-specific sampling and analysis plan inaccordance with Guide D5903. The decision should be made on a parameter-specific basis with consideration of the data qualityobjectives of the sampling program, any applicable regulatory agency guidelines, and analytical method requiremen
6、ts.1.3 This guide offers an organized collection of information or a series of options and does not recommend a specific courseof action. This guide cannot replace education or experience and should be used in conjunction with professional judgment. Notall aspects of this guide may be applicable in
7、all circumstances. This guide is not intended to represent or replace the standard ofcare by which the adequacy of a given professional service mustto be judged, nor should this guide be applied withoutconsideration of the many unique aspects of a project. The word “Standard” in the title of this gu
8、ide means only that the guidehas been approved through the ASTM consensus process.1.4 UnitsThe 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
9、be used independently of the other.Combining values from the two systems may result in non-conformance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish approp
10、riate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for
11、the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil, Rock, and Contained FluidsD5088 Practice for Decontamination of Field
12、 Equipment Used at Waste SitesD5092 Practice for Design and Installation of Groundwater Monitoring WellsD5903 Guide for Planning and Preparing for a Groundwater Sampling EventD6089 Guide for Documenting a Groundwater Sampling EventF740 Definitions of Terms Relating to Filtration (Withdrawn 2002)31 T
13、his 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 VadoseZone Investigations.Current edition approved May 15, 2012Dec. 15, 2017. Published December 2012 January 2018. Originally approved in 2000. Last
14、previous edition approved in 20052012as D6564 00 (2005).(2012)1. DOI: 10.1520/D6564-00R12E01.10.1520/D6564_D6564M-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to
15、the standards Document Summary page on the ASTM website.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. Becauseit may not be technically possible to adequately depict all changes
16、accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Ha
17、rbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions: DefinitionsFor definitions of common technical terms in this standard, refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 filter, vin groundwater sampling, to pass
18、a fluid containing particles through a filter medium whereby particles areseparated from the fluid. F7403.2.2 filter, nin groundwater sampling, a device for carrying out filtration which consists of the combination of the filtermedium and suitable hardware for constraining and supporting it in the p
19、ath of the fluid. F7403.2.3 filter mediummedium, nin groundwater sampling, the permeable material used for a filter that separates particles froma fluid passing through it. F7403.2.4 filter preconditioningthe process of preparing a filter medium for filtration3.2.4 filter systemsystem, nin groundwat
20、er sampling, the combination of one or more filter with all the associated processhardware required for filtration. F7403.2.6 filtratethe fluid that has passed through the filter. F7403.2.5 filtrationfiltration, vin groundwater sampling, the process by which particles are separated from a fluid by p
21、assing thefluid through a permeable material. F7403.2.6 filtered samplesample, nin groundwater sampling, a groundwater sample which has passed through a filter medium.3.2.6.1 DiscussionThis type of sample may also be referred to as a “dissolved” sample. An unfiltered sample containing dissolved, sor
22、bed,coprecipitated and all suspended particles may be referred to as a “total” sample.3.2.9 particlea small discrete mass of solid or liquid matter. F7404. Significance and Use4.1 A properlycorrectly designed, installed and developed groundwater monitoring well, constructed in accordance withPractic
23、e D5092, should facilitate collection of samples of groundwater that can be analyzed to determine both the physical andchemical properties of that sample. Samples collected from these wells that require analysis for dissolved constituents should befiltered in the field prior to chemical preservation
24、 and shipment to the laboratory for analysis.5. Purpose of Groundwater Sample Filtration5.1 Groundwater samples may be filtered to separate a defined fraction of the sample for analysis.6. Timing of Groundwater Sample Filtration6.1 Groundwater samples should be filtered immediately upon collection a
25、nd prior to chemical preservation of the sample.(1)Filtration should be completed in as short a time as possiblepracticable while minimizing sample aeration, agitation, pressurechanges, temperature changes and prolonged contact with ambient air.NOTE 1The pressure change that occurs when the sample i
26、s brought to the surface may cause changes in sample chemistry which include losses ofdissolved gases and precipitation of dissolved constituents such as metals. When handling samples during filtration operations, additional turbulence andmixing of the sample with air can cause aeration and oxidatio
27、n of dissolved ferrous to ferric iron. Ferric iron rapidly precipitates as amorphous ironhydroxide and can absorb other dissolved trace metals (21).)3.7. Groundwater Sample Filtration Procedures7.1 Preparation for Groundwater Sample FiltrationThe groundwater sample filtration process consists of thr
28、ee phases:selection of filtration method; selection and pretreatment of filter media; and groundwater sample filtration prior to transfer intothe sample container.7.1.1 Filtration Method Selection CriteriaAwide variety of methods are available for field filtration of groundwater samples.In general,
29、filtration equipment can be divided into positive pressure filtration and vacuum (negative pressure) filtration methods,each with several different filtration medium configurations. Groundwater samples undergo pressure changes as they are broughtfrom the saturated zone (where groundwater is under pr
30、essure greater than atmospheric) to the surface (where it is underatmospheric pressure), resulting in changes in sample chemistry. Vacuum filtration methods further exacerbate pressure changes.For this reason, positive pressure filtration methods are preferred. Table 1 presents equipment options ava
31、ilable for positivepressure and vacuum filtration of groundwater samples. Fig. 1 presents examples of common filter characteristics and applications.3 The last approved version of this historical standard is referenced on www.astm.org.3 The boldface numbers given in parentheses refer to a list of re
32、ferences at the end of the text.D6564/D6564M 1727.1.2 When selecting a filtration method, the following criteria should be evaluated on a site-by-site basis:7.1.2.1 Effect on sample integrity considering the potential for the following to occur:7.1.2.2 Sample aeration (Note 2),7.1.2.3 Sample agitati
33、on (Note 2),NOTE 2Sample aeration and increased agitation may result in sample chemical alteration.7.1.2.4 Change in partial pressure of sample constituents resulting from application of negative pressure to the sample duringfiltration,7.1.2.5 Sorptive losses of components from the sample onto the f
34、ilter medium or components of the filtration equipment (forexample, flasks, filter holders etc.); and the like); and7.1.2.6 Leaching of components from the filter medium or components of the filtration equipment into the sample.7.1.2.7 Volume of sample to be filtered;7.1.2.8 Chemical compatibility o
35、f filter medium with groundwater sample chemistry;7.1.2.9 Anticipated amount of suspended solids and the attendant effects of particulate loading (reduction in effective filter poresize);7.1.2.10 Time required to filter samples (Note 3);NOTE 3Short filtration times are recommended to minimize the ti
36、me available for chemical changes to occur in the sample.7.1.2.11 Ease of use;7.1.2.12 Availability of an appropriate medium in the desired filter pore size7.1.2.13 Filter surface area;7.1.2.14 Use of disposable versus non-disposable equipment;7.1.2.15 Ease of cleaning equipment if not disposable;7.
37、1.2.16 Potential for sample bias associated with ambient air contact during sample filtration; and7.1.2.17 Cost, evaluating the costs associated with: equipment purchase price, expendable supplies and their disposal, timerequiredneeded for filtration, time requiredneeded for decontamination of non-d
38、isposable equipment and quality control measures.7.1.2.18 The filtration method used for any given sampling program should be documented in the site-specific sampling andanalysis plan and should be consistent throughout the life of the sampling program to permit comparison of data generated. If anim
39、proved method of filtration is determined to be appropriate for a sampling program, the sampling and analysis plan should berevised and implemented in lieu of continuation of the existing filtration method. In this event, the effect on comparability of dataneeds to be examined and quantified to allo
40、w proper data analysis and interpretation (Note 4).NOTE 4Statistical methods may need to be implemented to determine the significance of any changes in data resulting from a change in filtrationmethod.7.1.3 Filtration Equipment Materials of ConstructionFiltration equipment and filtration media are a
41、vailable in a wide varietyof materials of construction. Materials of construction should be evaluated (for example, by contacting manufacturers, conductingleach tests or collecting equipment blanks) to minimize sample bias:7.1.3.1 Potential for negative bias due to adsorption of constituents from th
42、e sample (21);7.1.3.2 Potential for positive bias due to desorption or leaching of constituents into the sample (3-2-65);7.1.3.3 Reduction of the effective filter pore size caused by clogging when filtering water containing suspended particles; (65)and7.1.3.4 Aeration of the sample leading to precip
43、itation of some constituents (for example, ferric hydroxide) (32).7.1.4 Selection and Pretreatment of Filter MediaFiltration media are manufactured with specific pore size diameters designedto permit particles of a selected size to be retained by the filter medium. Filtration media must is to be sel
44、ected after consideringfilter pore size, and materials of construction. Groundwater samples requiring field filtration must are to be filtered using a mediumwith a pore size that meets the requirements of the approved sampling and analysis plan.7.1.5 Preconditioning of the Filtration Medium:TABLE 1
45、Examples of Equipment Options for Positive andNegative Pressure Filtration of Groundwater SamplesPositive Pressure Filtration Equipment: In-line capsulesattached directly to a pumping device discharge hoseattached to a pressurized transfer vesselattached to a pressurized bailer Free-standing disk fi
46、lter holders Syringe filters Zero headspace extraction vesselsNegative Pressure Filtration Equipment: Glass funnel support assemblyD6564/D6564M 1737.1.5.1 Filter media require preconditioning prior to sample filtration (76). Purposes of filter preconditioning include: tominimize positive sample bias
47、 associated with residues that may exist on the filter surface or constituents that may leach from thefilter; and to create a uniform wetting front across the entire surface of the filter to prevent channel flow through the filter andincrease the efficiency of the filter surface area. Preconditionin
48、g the filter medium may not completely prevent sorptive losses fromthe sample as it passes through the filter medium.7.1.5.2 In most cases, filter preconditioning should be done at the wellhead (Note 5) immediately prior to use. Somemanufacturers prerinse filters prior to sale. These filters are typ
49、ically marked “prerinsed”“pre-rinsed” on filter packaging andprovide directions for any if additional field preconditioning required is needed prior to filter use.NOTE 5Some filters require preconditioning procedures that can only be done in the laboratory (for example, GF/F filters must are to be baked priorto use).7.1.5.3 The procedure used to precondition the filter medium is determined by the following: the design of the filter (that is,filter capsules, or disks), the material of construction of the filter medium, the configuration of the f