1、Designation:D5521/D5521M18Standard Guide forDevelopment of Groundwater Monitoring Wells in GranularAquifers1This standard is issued under the fixed designation D5521/D5521M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of
2、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.Scope*1.1 This guide covers the development of screened wellsinstalled for the purpose of obtaining representative ground-water info
3、rmation and water quality samples from granularaquifers,though the methods described herein could also beapplied to wells used for other purposes.Other well-development methods that are used exclusively in open-borehole bedrock wells are not described in this guide.1.2 The applications and limitatio
4、ns of the methods de-scribed in this guide are based on the assumption that theprimary objective of the monitoring wells to which themethods are applied is to obtain representative water qualitysamples from aquifers.Screened monitoring wells developedusing the methods described in this guide should
5、yield rela-tively sediment-free samples from granular aquifer materials,ranging from gravels to silty sands.While many monitoringwells are considered“small-diameter”wells(that is,less than10 cm 4 in.inside diameter),some of the techniquesdescribed in this guide will be more easily applied to large-d
6、iameter wells(that is,10 cm 4 in.or greater insidediameter).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues
7、 from the two systems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and det
8、er-mine the applicability of regulatory limitations prior to use.1.5 This guide offers an organized collection of informationor a series of options and does not recommend a specificcourse of action.This document cannot replace education orexperience and should be used in conjunction with professiona
9、ljudgment.Not all aspects of this guide may be applicable in allcircumstances.This ASTM standard is not intended to repre-sent or replace the standard of care by which the adequacy ofa given professional service needs to be judged,nor should thisdocument be applied without consideration of a project
10、s manyunique aspects.The word“Standard”in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision
11、 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:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD3740 Practice for Minimum Requ
12、irements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD5088 Practice for Decontamination of Field EquipmentUsed at Waste SitesD5092 Practice for Design and Installation of GroundwaterMonitoring Wells3.Terminology3.1 Definitions:3.1.1
13、For definitions of common terminology terms usedwithin this standard,refer to Terminology D653.3.1.2 annular seal,nin groundwater,material used toprovide a seal between the borehole and the casing of a well.The annular seal should have a hydraulic conductivity less thanthat of the surrounding geolog
14、ic materials,be resistant tochemical or physical deterioration.1This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved June 1,2018.Published July 2018.Orig
15、inally approvedin 1994.Last previous edition approved in 2013 as D5521 13.DOI:10.1520/D5521_D5521M-18.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Docum
16、ent Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright 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 theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers
