1、Designation: C998 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 revision. A number in paren
2、theses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the sampling of surface soil for thepurpose of obtaining a sample representative of a particulararea for subsequent chemical anal
3、ysis of selected radionu-clides. This practice describes one acceptable approach tocollect soil samples for radiochemical analysis.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address
4、 all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance
5、 with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Stand
6、ards:2C859 Terminology Relating to Nuclear MaterialsD420 Guide to Site Characterization for Engineering Designand Construction Purposes (Withdrawn 2011)3D1129 Terminology Relating to Water2.2 Other References:MARLAP, Chapter 10IAEA-TECDOC-1415, Soil Sampling for EnvironmentalContaminants3. Terminolo
7、gy3.1 Except as otherwise defined herein, definitions of termsare as given in Terminology C859.3.2 Definitions:3.2.1 sampling, nobtaining a representative portion of thematerial concerned (see Terminology D1129).4. Summary of Practice4.1 Guidance is provided for the collection of soil samplesto a de
8、pth of 50 mm. Ten core samples are collected in aspecified pattern and composited to obtain sufficient sample soas to be representative of the area.5. Significance and Use5.1 Soil provides a source material for the determination ofselected radionuclides and serves as an integrator of thedeposition o
9、f airborne materials. Soil sampling should not beused as the primary measurement system to demonstratecompliance with applicable radionuclides in air standards. Thisshould be done by air sampling or by measuring emission rates.Soil sampling does serve as a secondary system, and in manycases, is the
10、only available avenue if insufficient air samplingoccurred at the time of an incident. For many insolubleradionuclides, the primary exposure pathway to the generalpopulation is by inhalation. The resuspension of transuranicelements has received considerable attention (1, 2)4and theirmeasurement in s
11、oil is one means of establishing compliancewith the U.S. Environmental Protection Agency (EPA) guide-lines on exposure to transuranic elements. Soil sampling canprovide useful information for other purposes, such as plantuptake studies, total inventory of various radionuclides in soildue to atmosphe
12、ric nuclear tests, and the accumulation ofradionuclides as a function of time. A soil sampling andanalysis program as part of a preoperational environmentalmonitoring program serves to establish baseline concentra-tions. Consideration was given to these criteria in preparingthis practice.5.2 Soil co
13、llected using this practice and subsequent analy-sis can be used to monitor radionuclide deposition of emissionsfrom nuclear facilities. The critical factors necessary to provide1This practice is under the jurisdiction of ASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Su
14、bcommittee C26.05 on Methods ofTest.Current edition approved June 1, 2017. Published July 2017. Originally approvedin 1983. Last previous edition approved in 2010 as C998 05 (2010)1. DOI:10.1520/C0998-17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
15、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4The boldface numbers in parentheses refer to the list of references at t
16、he end ofthis standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for
17、theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1this information are sampling location, time of sampling,frequency of sampling, sample size, and maintenance of theintegrity of the sample prior t
18、o analysis. Since the soil isconsidered to be a heterogeneous medium, multipoint samplingis necessary. The samples must represent the conditions exist-ing in the area for which data are desired.6. Apparatus6.1 Sampling Instrument5In order to standardize thesample collection, it is suggested that the
19、 coring tool be thatinstrument used by golf courses to place the hole in the puttinggreen. This instrument is commercially available at reasonablecost, has approximately a 0.105-m diameter barrel, and cantake samples down to 300 mm. An illustration of the samplinginstrument and its use is provided i
20、n Fig. 1.6.2 Sample Container, such as metal cans with lids, plasticbags, etc.6.3 Meter Stick.6.4 Small Scoop.7. Sampling7.1 IntroductionThe sampling depth for this practice is thetop 50 mm of soil. Experience has shown this depth is best forthis purpose (3) and has been proven to provide samples fo
21、r theanalysis of deposited radionuclides following a recent airbornerelease. The difference in concentration from previously col-lected samples at the same locations would be a measure of thecontamination. If the purpose of the sampling is to measure thetotal amount of a radionuclide deposited onto
22、the soil, that is,from fallout of previous atmospheric nuclear tests, then sam-pling must be conducted to a 300 mm depth. It is recommendedby the EPA (2) that soil sampling for plutonium be the top 10mm of soil. Although this may be a desirable depth forresuspension studies in certain parts of the c
23、ountry that havepowdery, dry, loose, sandy soils, in most areas, the vegetativecover and root mat make this an unworkable sampling depth.Because the data may be used in various ways, it is importantto accurately record the sample location, the depth of thesample, and the sample weight. In order to o
24、btain sufficientsample to be representative of the area, due to the inherentheterogeneity of soil, it is recommended that a total samplingarea of greater than 0.05 m2be collected as described inSection 8.7.2 Site Selection:7.2.1 As an idealized guideline, each site should be selectedon the basis tha
25、t the soil appears, or was known to have been,undisturbed for a number of years. Open, level, grassy areasthat are mowed at reasonable intervals, such as public parks,are suitable choices. The site should have moderate to goodpermeability and there should be little or no runoff duringheavy rains. Th
26、e site should not be near enough to buildings,trees, or other obstructions that it is sheltered or shielded. Highearthworm activity (as a result of direct observation of theremoved sample) or aeration of the root zone may result inuneven mixing of the surface soil and, therefore, this type ofsite sh
27、ould be avoided. Care should be taken not to select a sitethat is fertilized or watered with sources that may addradioactive materials to the soil, that is, some fertilizers havehigh uranium concentrations. It is important to be able toaccurately describe the location at which the sample wascollecte
28、d (the use of GPS is suggested) if it becomes necessaryto return and resample the location.7.2.2 The number of sites sampled is determined by thepurpose of the sampling and the information required from theparticular analysis. If the sampling is part of a preoperationalsurvey around a facility, one
29、acceptable distribution is thatproposed in HASL-300 (4) and depicted in Fig. 2. Thisdistribution of 13 sampling sites extending up to 10 km in thedownwind direction from the facility should be adequate to5Model 28200 Scalloped Style of the Standard Manufacturing Company ofCedar Falls, IA, or its equ
30、ivalent, has been found satisfactory for this purpose.FIG. 1 Soil Sampling Instrument and Use FIG. 2 Soil Sampling PatternC998 172provide the background concentration of the nuclides ofinterest. Sampling for other purposes may require other distri-bution of sites, while sampling to define the distri
31、bution of anuclide from a specific incident would require extensiveknowledge of meteorological and climatological factors. It isimportant that the purpose of the sampling dictate the sampledistribution.8. Procedure8.1 Sampling Procedure:8.1.1 Select the sampling location based on Section 7.8.1.2 Mea
32、sure out two 1-m2areas, about 3 m apart.8.1.3 Remove all vegetation to a height of 10 to 20 mmabove the soil and save if desired.8.1.4 Collect soil from the center and each corner of the two1-m2areas.8.1.5 Insert the sampling tool to a depth of 50 mm below thesoil surface and remove the soil plug.8.
33、1.6 Place the soil plug and residual vegetation and roots inan 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 sampled.8
34、.1.9 Clean the sampling tools in water and detergent anddry before collecting the next sample.8.2 Sampling RationaleThe intent of the sampling proce-dure is to define the operational steps necessary to collect arepresentative sample from a desired location. The selection ofthe sampling tool should b
35、e dictated by local soil conditions asit is not the intent of this practice to identify one instrument tothe exclusion of all others. However, two common procedures,or variations thereof, are most frequently used. These twoprocedures are the core procedure and the ring procedure.Because of the large
36、 variation in soil types, the core methoddescribed in HASL-300 (4) is recommended where applicable,and a ring method used by the Nevada Applied Ecology Group(NAEG) is offered as an option (5) for dry, sandy soils. Theconcepts and techniques in this practice are applicable to mostsituations requiring
37、 sampling surface soil for radionuclides.8.3 Core ProcedureThe collection of ten cores willsample about 0.086 m2of soil surface. Composite the ten coresto produce a single sample of about 4 to 5 kg. Most soilscontain sufficient moisture to be cohesive and the plug can beremoved intact. For some type
38、s of dry, loose soils, wetting theground by sprinkling prior to sampling may allow the plug tobe removed. Place the plugs in a container, seal, and carefullylabel. Clean the sampling tools in water and detergent and drybefore proceeding to the next sample collection site.8.4 Ring ProcedureFor the dr
39、y, loose, sandy soil forwhich the core method is not applicable, press a ring, 100 mmin diameter and 50 mm deep, into the soil. Remove the soilinside the ring with a small scoop to a depth of 50 mm andplace into a container. Repeat this until a total of ten cores arecollected, using the procedure ou
40、tlined in Section 7 for samplelocation selection. Clean the sampling tools in water anddetergent and dry before proceeding to the next samplecollection site.9. Discussion9.1 Either method works well for fine-grained soils, butdifficulties occur with rocky soils. For samples in whichplutonium is the
41、element of interest, the rocks may beconsidered voids in the sample and usually are discardedduring sample preparation. If this is the case, larger numbers ofcores, and therefore larger areas, should be sampled to ensurethat the sample is representative of the site. If it is necessary toremove large
42、 rocks, this should be noted in the sampling plan.9.2 The sampling techniques described in this practice willprovide sufficient information to allow the calculation ofresults in terms of deposition per unit area or concentration. Ifthe sampling is part of a routine monitoring program, it may beneces
43、sary to repeat the sampling at each location and compareresults to determine the effect of facility operation.10. Keywords10.1 environmental; radionuclides; sampling; soilREFERENCES(1) “Proposed Guidance on Dose Limits for Persons Exposed to Transu-ranium Elements in the General Environment,” Enviro
44、nmental Pro-tection Agency 520/4-77-016, 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 andAnalysis of Plutonium in Soil,” Atomic Energy Commission Regula-
45、tory Guide 4.5, 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 Soilsfor Radioactivity: Philosophy, Experience, and Results,”Atmospheric-Surface Exchange of Particulate and GaseousPoll
46、utants, ERDA Symposium Series 38, 1974, pp. 706727.C998 173ASTM 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 advised that determination of the validity of any such pat
47、ent 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 reapproved or withdrawn. Your comments are invited eit
48、her 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
49、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 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright C
