ASTM_D_5881_-_13.pdf

Designation:D588113Standard Test Method for(Analytical Procedure)Determining Transmissivity ofConfined Nonleaky Aquifers by Critically Damped WellResponse to Instantaneous Change in Head(Slug)1This standard is issued under the fixed designation D5881;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 test method covers determination of transmissivityfrom the measurement of water-level response to a suddenchange of water level in a well-aquifer system characterized asbeing critically damped or in the transition range from under-damped to overdamped.Underdamped response is character-ized by oscillatory changes in water level;overdamped re-sponse is characterized by return of the water level to the initialstatic level in an approximately exponential manner.Over-damped response is covered in Guide D4043;underdampedresponse is covered in D5785,D4043.1.2 The analytical procedure in this test method is used inconjunction with Guide D4043 and the field procedure in TestMethod D4044 for collection of test data.1.3 LimitationsSlug tests are considered to provide anestimate of the transmissivity of an aquifer near the wellscreen.The method is applicable for systems in which thedamping parameter,is within the range from 0.2 through 5.0.The assumptions of the method prescribe a fully penetratingwell(a well open through the full thickness of the aquifer)ina confined,nonleaky aquifer.1.4 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.5 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.1.5.1 The procedures used to specify how data are collected/recorded or calculated,in this standard are regarded as theindustry standard.In addition,they are representative of thesignificant digits that generally should be retained.The proce-dures used do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives and it is common practice toincrease to reduce significant digits of reported data to becommensurate with these considerations.It is beyond the scopeof this standard to consider significant digits used in analyticalmethods for design.1.6 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 and health practices and determine the applica-bility of regulatory limitations prior to use.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 TechniquesD4044 Test Method for(Field Procedure)for InstantaneousChange in Head(Slug)Tests for Determining HydraulicProperties of AquifersD5785 Test Method for(Analytical Procedure)for Deter-mining Transmissivity of Confined Nonleaky Aquifers byUnderdamped Well Response to Instantaneous Change inHead(Slug Test)D6026 Practice for Using Significant Digits in GeotechnicalData3.Terminology3.1 DefinitionsFor definitions of common technical termsin this standard,refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 aquifer,confinedan aquifer bounded above and be-low by confining beds and in which the static head is above thetop of the aquifer.1This test method is under the jurisdiction ofASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Groundwater andVadose Zone Investigations.Current edition approved Nov.15,2013.Published December 2013.Originallyapproved in 1995.Last previous edition approved in 2005 as D5881 95(2005).DOI:10.1520/D5881-13.2For 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 States1 3.2.2 critically damped well responsecharacterized by thewater level responding in a transitional range between under-damped and overdamped following a sudden change in waterlevel.3.2.3 observation wella well open to all or part of anaquifer.3.3 Symbols and Dimensions:3.3.1 Ttransmissivity L2T1.3.3.2 Sstorage coefficient nd.3.3.3 Lstatic water column length above top of aquiferL.3.3.4 Leeffective length