ASTM_D_5855_-_D_5855M_-_20.pdf

Designation:D5855/D5855M20Standard Practice for(Analytical Procedure)Determining Transmissivity andStorage Coefficient of Confined Nonleaky or Leaky Aquiferby Constant Drawdown Method in Flowing Well1This standard is issued under the fixed designation D5855/D5855M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of 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 practice covers an analytical solution for determin-ing transmissivity and storage coefficient of a leaky or non-leaky confined aquifer.It is used to analyze data on the flowrate from a control well while a constant head is maintained inthe well.1.2 This analytical procedure is used in conjunction with thefield procedure in Practice D5786.1.3 LimitationsThe limitations of this technique for thedetermination of hydraulic properties of aquifers are primarilyrelated to the correspondence between field situation and thesimplifying assumption of the solution.1.4 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues in each system may not be exact equivalents;thereforeeach system shall be used independently of the other.Combin-ing values from the two systems may result in non-conformance with the standard.Reporting of test results inunits other than SI shall not be regarded as nonconformancewith this practice.1.5 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.6 This practice offers a set of instructions for performingone or more specific operations.This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment.Not all aspects of the practice maybe applicable in all circumstances.This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a given professional service must be judged,nor should this document be applied without the considerationof a projects many unique aspects.The word“Standard”inthe title of this document means only that the document hasbeen approved through the ASTM consensus process.1.7 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.1.8 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 ConstructionD4043 Guide for Selection of Aquifer Test Method inDetermining Hydraulic Properties by Well TechniquesD5786 Practice for(Field Procedure)for Constant Draw-down Tests in Flowing Wells for Determining HydraulicProperties of Aquifer SystemsD6026 Practice for Using Significant Digits in GeotechnicalData3.Terminology3.1 Derfinitions:3.1.1 For definitions of common technical terms used in thispractice,refer to Terminology D653.3.2 Symbols and Dimensions:3.2.1 Ttransmissivity L2T1.1This practice is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved May 15,2020.Published May 2020.Originallyapproved in 1995.Last previous edition approved in 2015 as D5855 15.DOI:10.1520/D5855_D5855M-20.2For 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.3.2.2 K1modified Bessel function of the second kind,firstorder nd.3.2.3 K2modified Bessel function of the second kind,zeroorder nd.3.2.4 J0Bessel function of the first kind,zero order nd.3.2.5 Y0Bessel function of the second kind,zero ordernd.3.2.6 W(u)w(well