1、Designation:D826521Standard Practices forElectrical Methods for Mapping Leaks in InstalledGeomembranes1This standard is issued under the fixed designation D8265;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.1.Scope1.1 These practices describe standard procedures for usingelectrical methods to locate leaks in geomembranes coveredwith liquid or earthen
3、materials,or both.1.2 These practices are intended to ensure that leak locationsurveys are performed to the highest technical capability ofelectrical methods,which should result in complete liquidcontainment(no leaks in geomembrane).1.3 Not all sites will be easily amenable to this method,butsome pr
4、eparation can be performed in order to enable thismethod at nearly any site as outlined in Section 6.If idealtesting conditions cannot be achieved,the method can still beperformed,but any issues with site conditions are documented.1.4 Leak location surveys can be used on geomembranesinstalled in bas
5、ins,ponds,tanks,ore and waste pads,landfillcells,landfill caps,and other containment facilities.Theprocedures are applicable for geomembranes made of materialssuch as polyethylene,polypropylene,polyvinyl chloride,chlo-rosulfonated polyethylene,bituminous material,and othersufficiently electrically i
6、nsulating materials.1.5 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.6 The electrical methods used for geomembrane leaklocation should be attempted only by qualified and experiencedpersonnel.Appropriate safety measures shoul
7、d be taken toprotect the leak location operators,as well as other people atthe site.A current limiter of no greater than 290 mA should beused for all direct current power sources used to conduct thesurvey.1.7 This standard does not purport to address all of thesafety concerns,if any,associated with
8、its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized princi
9、ples 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 Standards:2D4439 Terminology for GeosyntheticsD7
10、909 Guide for Placement of Intentional Leaks DuringElectrical Leak Location Surveys of Geomembranes3.Terminology3.1 For general definitions related to geosynthetics,seeTerminology D4439.3.2 Definitions of Terms Specific to This Standard:3.2.1 actual leak,nfor the purposes of this standard,theterm“ac
11、tual leak”is used for a leak to distinguish it from anartificial leak.3.2.2 anomaly,nelectrical measurement caused by someaberration in the survey area,which may or may not be a leak.3.2.3 artificial leak,nfor the purposes of this standard,anartificial leak is an electrically insulated disk with a c
12、ircularconductive electrode,which electrically mimics a leak in thelining system and is used to confirm method functionalitywithout creating an actual leak in the lining system.3.2.4 conductive-backed geomembrane,na specialtygeomembrane manufactured using co-extrusion technologyfeaturing an insulati
13、ng layer in intimate contact with a conduc-tive layer.3.2.5 current source electrode,nthe electrode that isplaced in the water or earthen material above the geomem-brane.1These practices are under the jurisdiction of ASTM Committee D35 onGeosynthetics and are the direct responsibility of Subcommitte
14、e D35.10 onGeomembranes.Current edition approved May 1,2021.Published May 2021.Originallyapproved in 2019.Last previous edition approved in 2020 as D8265 20.DOI:10.1520/D8265-21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For
15、Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.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 rec
16、ognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.13.2.6 dipole measurement,nan electrical measurementmade on or in a partially conductive material using two closelyspaced electrodes.3.2.7 earthen material,nsand,gravel,clay,silt,combina-tions of these materials,and similar materials.3.2.8 electrically isolated cond
