1、Designation: C998 05 (Reapproved 2010)1C998 17Standard Practice forSampling Surface Soil for Radionuclides1This standard is issued under the fixed designation C998; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1 NOTEThe units statement in subsection 1.2 was added editorially in June 2010.1. Scope1.1 This practice covers the sampling of surface
3、soil for the purpose of obtaining a sample representative of a particular areafor subsequent chemical analysis of selected radionuclides. This practice describes one acceptable approach to collect soil samplesfor radiochemical analysis.1.2 The values stated in SI units are to be regarded as standard
4、. No other units of measurement are included in this standard.1.3 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 appropriate safety and health practices and determine the applica
5、bility of regulatorylimitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the Worl
6、d Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C859 Terminology Relating to Nuclear MaterialsD420 Guide to Site Characterization for Engineering Design and Construction Purposes (Withdrawn 2011)3D1129 Terminology Relating to Water2.2 Other
7、 References:MARLAP, Chapter 10IAEA-TECDOC-1415, Soil Sampling for Environmental Contaminants3. Terminology3.1 Except as otherwise defined herein, definitions of terms are as given in Terminology C859.3.2 Definitions:3.2.1 sampling, nobtaining a representative portion of the material concerned (see T
8、erminology D1129).4. Summary of Practice4.1 Guidance is provided for the collection of soil samples to a depth of 50 mm. Ten core samples are collected in a specifiedpattern and composited to obtain sufficient sample so as to be representative of the area.5. Significance and Use5.1 Soil provides a s
9、ource material for the determination of selected radionuclides and serves as an integrator of the depositionof airborne materials. Soil sampling should not be used as the primary measurement system to demonstrate compliance withapplicable radionuclides in air standards. This should be done by air sa
10、mpling or by measuring emission rates. Soil sampling doesserve as a secondary system, and in many cases, is the only available avenue if insufficient air sampling occurred at the time ofan incident. For many insoluble radionuclides, the primary exposure pathway to the general population is by inhala
11、tion. The1 This practice is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of Test.Current edition approved June 1, 2010June 1, 2017. Published June 2010July 2017. Originally approved in 1983. Last previous editio
12、n approved in 20052010 asC998 05.C998 05 (2010)1. DOI: 10.1520/C0998-05R10E01.10.1520/C0998-17.2 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 the standards Document
13、 Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.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 m
14、ay not be technically possible to adequately depict all changes 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.Copyright ASTM International, 100 Barr Har
15、bor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1resuspension of transuranic elements has received considerable attention (1, 2)4 and their measurement in soil is one means ofestablishing compliance with the U.S. Environmental Protection Agency (EPA) guidelines on exposure to
16、transuranic elements.Soil sampling can provide useful information for other purposes, such as plant uptake studies, total inventory of variousradionuclides in soil due to atmospheric nuclear tests, and the accumulation of radionuclides as a function of time.Asoil samplingand analysis program as part
17、 of a preoperational environmental monitoring program serves to establish baseline concentrations.Consideration was given to these criteria in preparing this practice.5.2 Soil collected using this practice and subsequent analysis can be used to monitor radionuclide deposition of emissions fromnuclea
18、r facilities. The critical factors necessary to provide this information are sampling location, time of sampling, frequency ofsampling, sample size, and maintenance of the integrity of the sample prior to analysis. Since the soil is considered to be aheterogeneous medium, multipoint sampling is nece
19、ssary. The samples must represent the conditions existing in the area for whichdata are desired.6. Apparatus6.1 Sampling Instrument5In order to standardize the sample collection, it is suggested that the coring tool be that instrumentused by golf courses to place the hole in the putting green. This
20、instrument is commercially available at reasonable cost, hasapproximately a 0.105-m diameter barrel, and can take samples down to 300 mm. An illustration of the sampling instrument andits use is provided in Fig. 1.6.2 Sample Container, such as metal cans with lids, plastic bags, etc.6.3 Meter Stick.
21、6.4 Small Scoop.7. Sampling7.1 IntroductionThe sampling depth for this practice is the top 50 mm of soil. Experience has shown this depth is best forthis purpose (3) and has been proven to provide samples for the analysis of deposited radionuclides following a recent airbornerelease. The difference
22、in concentration from previously collected samples at the same locations would be a measure of thecontamination. If the purpose of the sampling is to measure the total amount of a radionuclide deposited onto the soil, that is, fromfallout of previous atmospheric nuclear tests, then sampling must be
23、conducted to a 300 mm depth. It is recommended by the EPA(2) that soil sampling for plutonium be the top 10 mm of soil. Although this may be a desirable depth for resuspension studies incertain parts of the country that have powdery, dry, loose, sandy soils, in most areas, the vegetative cover and r
24、oot mat make this4 The boldface numbers in parentheses refer to the list of references at the end of this standard.5 Model 28200 Scalloped Style of the Standard Manufacturing Company of Cedar Falls, IA, or its equivalent, has been found satisfactory for this purpose.FIG. 1 Soil Sampling Instrument a
25、nd UseC998 172an unworkable sampling depth. Because the data may be used in various ways, it is important to accurately record the samplelocation, the depth of the sample, and the sample weight. In order to obtain sufficient sample to be representative of the area, dueto the inherent heterogeneity o
26、f soil, it is recommended that a total sampling area of greater than 0.05 m2 be collected as describedin Section 8.7.2 Site Selection:7.2.1 As an idealized guideline, each site should be selected on the basis that the soil appears, or was known to have been,undisturbed for a number of years. Open, l
27、evel, grassy areas that are mowed at reasonable intervals, such as public parks, aresuitable choices. The site should have moderate to good permeability and there should be little or no runoff during heavy rains.The site should not be near enough to buildings, trees, or other obstructions that it is
28、 sheltered or shielded. High earthworm activity(as a result of direct observation of the removed sample) or aeration of the root zone may result in uneven mixing of the surfacesoil and, therefore, this type of site should be avoided. Care should be taken not to select a site that is fertilized or wa
29、tered withsources that may add radioactive materials to the soil, that is, some fertilizers have high uranium concentrations. It is importantto be able to accurately describe the location at which the sample was collected (the use of GPS is suggested) if it becomesnecessary to return and resample th
30、e location.7.2.2 The number of sites sampled is determined by the purpose of the sampling and the information required from the particularanalysis. If the sampling is part of a preoperational survey around a facility, one acceptable distribution is that proposed inHASL-300 (4) and depicted in Fig. 2
31、. This distribution of 13 sampling sites extending up to 10 km in the downwind direction fromthe facility should be adequate to provide the background concentration of the nuclides of interest. Sampling for other purposesmay require other distribution of sites, while sampling to define the distribut
32、ion of a nuclide from a specific incident would requireextensive knowledge of meteorological and climatological factors. It is important that the purpose of the sampling dictate thesample distribution.8. Procedure8.1 Sampling Procedure:8.1.1 Select the sampling location based on Section 7.8.1.2 Meas
33、ure out two 1-m2 areas, about 3 m apart.8.1.3 Remove all vegetation to a height of 10 to 20 mm above the soil and save if desired.8.1.4 Collect soil from the center and each corner of the two 1-m2 areas.8.1.5 Insert the sampling tool to a depth of 50 mm below the soil surface and remove the soil plu
34、g.8.1.6 Place the soil plug and residual vegetation and roots in an appropriate container.8.1.7 Repeat the procedure until the ten cores are collected. Composite the ten cores as one sample.8.1.8 Label the container with such information as location, time, date, collector, depth of core, and area sa
35、mpled.8.1.9 Clean the sampling tools in water and detergent and dry before collecting the next sample.8.2 Sampling RationaleThe intent of the sampling procedure is to define the operational steps necessary to collect arepresentative sample from a desired location. The selection of the sampling tool
36、should be dictated by local soil conditions as itis not the intent of this practice to identify one instrument to the exclusion of all others. However, two common procedures, orvariations thereof, are most frequently used. These two procedures are the core procedure and the ring procedure. Because o
37、f thelarge variation in soil types, the core method described in HASL-300 (4) is recommended where applicable, and a ring methodFIG. 2 Soil Sampling PatternC998 173used by the Nevada Applied Ecology Group (NAEG) is offered as an option (5) for dry, sandy soils. The concepts and techniquesin this pra
38、ctice are applicable to most situations requiring sampling surface soil for radionuclides.8.3 Core ProcedureThe collection of ten cores will sample about 0.086 m2 of soil surface. Composite the ten cores to producea single sample of about 4 to 5 kg. Most soils contain sufficient moisture to be cohes
39、ive and the plug can be removed intact. Forsome types of dry, loose soils, wetting the ground by sprinkling prior to sampling may allow the plug to be removed. Place theplugs in a container, seal, and carefully label. Clean the sampling tools in water and detergent and dry before proceeding to thene
40、xt sample collection site.8.4 Ring ProcedureFor the dry, loose, sandy soil for which the core method is not applicable, press a ring, 100 mm in diameterand 50 mm deep, into the soil. Remove the soil inside the ring with a small scoop to a depth of 50 mm and place into a container.Repeat this until a
41、 total of ten cores are collected, using the procedure outlined in Section 7 for sample location selection. Cleanthe sampling tools in water and detergent and dry before proceeding to the next sample collection site.9. Discussion9.1 Either method works well for fine-grained soils, but difficulties o
42、ccur with rocky soils. For samples in which plutonium isthe element of interest, the rocks may be considered voids in the sample and usually are discarded during sample preparation. Ifthis is the case, larger numbers of cores, and therefore larger areas, should be sampled to ensure that the sample i
43、s representativeof the site. If it is necessary to remove large rocks, this should be noted in the sampling plan.9.2 The sampling techniques described in this practice will provide sufficient information to allow the calculation of results interms of deposition per unit area or concentration. If the
44、 sampling is part of a routine monitoring program, it may be necessaryto repeat the sampling at each location and compare results to determine the effect of facility operation.10. Keywords10.1 environmental; radionuclides; sampling; soilREFERENCES(1) “Proposed Guidance on Dose Limits for Persons Exp
45、osed to Transuranium Elements in the General Environment,” Environmental ProtectionAgency520/4-77-016, October 1977.(2) “Persons Exposed to Transuranium Elements in the Environment,” Federal Register, Vol 42, No. 230, Nov. 30, 1977.(3) “Measurements of Radionuclides in the Environment: Sampling and
46、Analysis of Plutonium in Soil,” Atomic Energy Commission Regulatory Guide4.5, May 1974.(4) Harley, J. H., ed., “EML Procedures Manual,” D.O.E. Report HASL-300, August 1979.(5) Fowler, F. B., Gilbert, R. O., and Essington, E. H., “Sampling of Soils for Radioactivity: Philosophy, Experience, and Resul
47、ts,”Atmospheric-SurfaceExchange of Particulate and Gaseous Pollutants, ERDA Symposium Series 38, 1974, pp. 706727.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly adv
48、ised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either
49、 reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428
