1、Designation:D623518Standard Practice forExpedited Site Characterization of Vadose Zone andGroundwater Contamination at Hazardous WasteContaminated Sites1This standard is issued under the fixed designation D6235;the number immediately following the designation indicates the year oforiginal adoption o
2、r,in the case of revision,the year of last revision.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 Applicability of the ESC ProcessThis practice coversa process for expedited site char
3、acterization(ESC)of hazard-ous waste contaminated sites2to identify vadose zone,ground-water and other relevant contaminant migration pathways anddetermine the distribution,concentration,and fate of contami-nants for the purpose of providing an ESC client,regulatoryauthority,and stakeholders with th
4、e necessary information tochoose a course of action.3Generally,the process is applicableto larger-scale projects or contaminated sites where the ESCprocess can be reasonably expected to reduce the time and costof site characterization compared to alternative approaches.The ESC process has been appli
5、ed successfully at a variety ofsites(see Table X1.1).It typically achieves significant cost andschedule savings compared to traditional site characterization(see X1.2 and X1.3),4although it should be recognized thatin-depth site characterization of hazardous waste contaminatedsites may require a mor
6、e elaborate process than ESC.1.2 Features of the ESC ProcessThe ESC process oper-ates within the framework of existing regulatory programs.Itfocuses on collecting only the information required to meetcharacterization objectives and on ensuring that characteriza-tion ceases as soon as the objectives
7、are met.Central to theESC process is the use of judgement-based sampling andmeasurement to characterize vadose zone and groundwatercontamination in a limited number of field mobilizations by anintegrated multidisciplinary team,led by a technical leader andoperating within the framework of a dynamic
8、work plan thatgives him or her the flexibility of responsibility to select thetype and location of measurements needed to optimize datacollection activities.Table 1 identifies other essential featuresof the ESC process,and Fig.1 presents a flow diagram for theentire ESC process.1.3 Investigation Met
9、hodsThe process described in thispractice is based on good scientific practice but is not tied toany particular regulatory program,site investigation method ortechnique,chemical analysis method,statistical analysismethod,risk analysis method,or computer modeling code.Appropriate investigation techni
10、ques in an ESC project arehighly site specific and are selected and modified based uponthe professional judgement of the core technical team(inparticular the technical team leader).Whenever feasible,non-invasive and minimally invasive methods are used,as dis-cussed in Appendix X2.Appropriate chemica
11、l analysis meth-ods are equally site specific.Analyses may be conducted in thefield or laboratory,depending on data quality requirements,required turnaround time,and costs.1.4 Sites Generally Not Appropriate for the ESC ProcessGenerally,the ESC process is not applicable to:small petro-leum release s
12、ites,real estate property transactions that requireno more than a Phase I ESA,sites where contamination islimited to the near surface or there is no basis for suspectingthat contaminant movement through the vadose zone andgroundwater is a matter of concern,sites where the cost ofremedial action is l
13、ikely to be less than the cost of sitecharacterization,or sites where existing statutes or regulationsprohibit the use of essential features of the ESC process.51.5 Other Potentially Applicable ASTM Standards for SiteCharacterizationGuide E1912 addresses accelerated site1This practice is under the j
14、urisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.01 on Surface andSubsurface Characterization.Current edition approved Dec.15,2018.Published January 2019.Originallyapproved in 1998.Last previous edition approved in 2010 as D6235 04(2010).DOI:10.1
15、520/D6235-18.2The term hazardous waste in the title is used descriptively.The term also hasspecific meanings in the context of different regulatory programs.Expedited sitecharacterization is also appropriate for radiologically contaminated sites and somelarger petroleum release sites,such as refiner
16、ies.Section 4.2 further identifies typesof contaminated sites where ESC may be appropriate.See Appendix X1 foradditional background on the ESC process.3The text of this practice emphasizes vadose zone and groundwater contamina-tion because these contaminant migration pathways are the most difficult tocharacterize.An ESC project should also address all other relevant contaminantmigration pathways,such as air,surface water,submerged sediments,and biota.4This practice uses the term“traditional”site
