ASTM_D_4448_-_01_2013.pdf

Designation:D444801(Reapproved 2013)Standard Guide forSampling Ground-Water Monitoring Wells1This standard is issued under the fixed designation D4448;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide covers sampling equipment and proceduresand“in the field”preservation,and it does not include welllocation,depth,well development,design and construction,screening,or analytical procedures that also have a significantbearing on sampling results.This guide is intended to assist aknowledgeable professional in the selection of equipment forobtaining representative samples from ground-water monitor-ing wells that are compatible with the formations beingsampled,the site hydrogeology,and the end use of the data.1.2 This guide is only intended to provide a review of manyof the most commonly used methods for collecting ground-water quality samples from monitoring wells and is notintended to serve as a ground-water monitoring plan for anyspecific application.Because of the large and ever increasingnumber of options available,no single guide can be viewed ascomprehensive.The practitioner must make every effort toensure that the methods used,whether or not they are ad-dressed in this guide,are adequate to satisfy the monitoringobjectives at each site.1.3 The values stated in SI units are to be regarded asstandard.The values given in parentheses are provided forinformation only.1.4 This standard does not purport to address all of thesafety problems,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.2.Referenced Documents2.1 ASTM Standards:2D4750 Test Method for Determining Subsurface LiquidLevels in a Borehole or Monitoring Well(ObservationWell)(Withdrawn 2010)3D5088 Practice for Decontamination of Field EquipmentUsed at Waste SitesD5792 Practice for Generation of Environmental Data Re-lated to Waste Management Activities:Development ofData Quality ObjectivesD5903 Guide for Planning and Preparing for a GroundwaterSampling EventD6089 Guide for Documenting a Groundwater SamplingEventD6452 Guide for Purging Methods for Wells Used forGroundwater Quality InvestigationsD6517 Guide for Field Preservation of GroundwaterSamples2.2 EPA Standards:EPA Method 9020AEPA Method 90223.Terminology3.1 Definitions:3.1.1 low-flow samplinga ground water sampling tech-nique where the purge and sampling rates do not result insignificant changes in formation seepage velocity.3.1.2 minimal purge samplingthe collection of groundwater that is representative of the formation by purging onlythe volume of water contained by the sampling equipment(thatis,tubing,pump bladder).3.1.2.1 DiscussionThis sampling method should be con-sidered in situations where very low yield is a considerationand results from this sampling method should be scrutinized toconfirm that they meet data quality objectives(DQOs)and thework plan objectives.3.1.3 passive samplingthe collection of ground-waterquality data so as to induce no hydraulic stress on the aquifer.3.1.4 water quality indicator parametersrefer to fieldmonitoring parameters that include but are not limited to pH,specific conductance,dissolved oxygen,oxidation-reductionpotential,temperature,and turbidity that are used to monitorthe completeness of purging.1This guide is under the jurisdiction of ASTM Committee D34 on WasteManagement and is the direct responsibility of Subcommittee D34.01.02 onSampling Techniques.Current edition approved April 1,2013.Published April 2013.Originallyapproved in 1985.Last previous edition approved in 2007 as D444801(2007).DOI:10.1520/D4448-01R13.2For 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 Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Summary of Guide4.1 The equipment and procedures used for sampling amonitoring well depend on many factors.These include,butare not limited to:the design and construction of the well,rateof ground-water flow,and the chemical species of interest.Sampling procedures may be different if analyses for traceorganics,volatiles,oxidizable species,or trace metals areneeded.This guide considers all of these factors by discussingequipment and procedure options at each stage of the samplingsequence.For ease of organization,the sampling process canbe divided into three steps:well purging,sample withdrawal,and field pre