ASTM_D_4696_-_18.pdf

Designation:D469618Standard Guide forPore-Liquid Sampling from the Vadose Zone1This standard is issued under the fixed designation D4696;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.Scope*1.1 This guide covers the equipment and procedures usedfor sampling pore-liquid from the vadose zone(unsaturatedzone).The guide is limited to in situ techniques and does notinclude soil core collection and extraction methods for obtain-ing samples.1.2 The term“pore-liquid”is applicable for liquids fromaqueous pore-liquid to oil.However,the samplers described inthis guide were designed,and are used to sample aqueouspore-liquids only.The abilities of these samplers to collectother pore-liquids may be quite different than those described.1.3 Some of the samplers described in this guide are notcurrently commercially available.These samplers are pre-sented because they may have been available in the past,andmay be encountered at sites with established vadose zonemonitoring programs.In addition,some of these designs areparticularly suited to specific situations.If needed,thesesamplers could be fabricated.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 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 deter-mine the applicability of regulatory limitations prior to use.1.6 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 professionaljudgment.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 must be judged,nor should thisdocument be applied without consideration of a projects manyunique aspects.The word“Standard”in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.1.7 This international standard was developed in accor-dance 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 Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and Construction3.Terminology3.1 Definitions3.1.1 For common definitions of terms in this standard,referto Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 air entry value,nin vadose zone,the applied suctionat which water menisci of the porous segment of a suctionsampler break down,and air enters.3.2.2 bubbling pressure,nin vadose zone,the applied airpressure at which water menisci of the porous segment of asuction sampler break down,and air exits.3.2.3 cascading water,nin groundwater,perched ground-water that enters a well casing via cracks or uncoveredperforations,trickling,or pouring down the inside of thecasing.3.2.4 hydrophobicity,nin vadose zone,the property thatdefines a material as being water repellent.Water exhibits anobtuse contact angle with hydrophobic materials.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 Nov.15,2018.Published November 2018.Originallyapproved in 1992.Last previous edition approved in 2008 as D4696 92(2008),which was withdrawn January 2017 and reinstated in November 2018.DOI:10.1520/D4696-18.2For 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 Document 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 to Trade(TBT)Committee.1 3.2.5 matric potential,nin vadose zone,the energy neede