ASTM_D_4104_-_96_2010e1.pdf

Designation:D410496(Reapproved 2010)1Standard Test Method(Analytical Procedure)for Determining Transmissivity ofNonleaky Confined Aquifers by Overdamped Well Responseto Instantaneous Change in Head(Slug Tests)1This standard is issued under the fixed designation D4104;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.1NOTEThe units statement in 1.4 was revised editorially in August 2010.1.Scope1.1 This test method covers the determination of transmis-sivity from the measurement of force-free(overdamped)re-sponse of a well-aquifer system to a sudden change of waterlevel in a well.Force-free response of water level in a well toa sudden change in water level is characterized by recovery toinitial water level in an approximate exponential manner withnegligible inertial effects.1.2 The analytical procedure in this test method is used inconjunction with the field procedure in Test Method D4044 forcollection of test data.1.3 LimitationsSlug tests are considered to provide anestimate of transmissivity.Although the assumptions of thistest method prescribe a fully penetrating well(a well openthrough the full thickness of the aquifer),the slug test methodis commonly conducted using a partially penetrating well.Such a practice may be acceptable for application underconditions in which the aquifer is stratified and horizontalhydraulic conductivity is much greater than vertical hydraulicconductivity.In such a case the test would be considered to berepresentative of the average hydraulic conductivity of theportion of the aquifer adjacent to the open interval of the well.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 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 ContainedFluidsD4043 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 AquifersD4750 Test Method for Determining Subsurface LiquidLevels in a Borehole or Monitoring Well(ObservationWell)(Withdrawn 2010)3D5912 Test Method for(Analytical Procedure)DeterminingHydraulic Conductivity of an Unconfined Aquifer byOverdamped Well Response to Instantaneous Change inHead(Slug)(Withdrawn 2013)33.Terminology3.1 Definitions:3.1.1 aquifer,confinedan aquifer bounded above and be-low by confining beds and in which the static head is above thetop of the aquifer.3.1.2 confining beda hydrogeologic unit of less permeablematerial bounding one or more aquifers.3.1.3 control wellwell by which the aquifer is stressed,forexample,by pumping,injection,or change of head.3.1.4 head,staticthe height above a standard datum of thesurface of a column of water(or other liquid)that can besupported by the static pressure at a given point.3.1.5 hydraulic conductivity(field aquifer tests),the vol-ume of water at the existing kinematic viscosity that will move1This 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 Aug.1,2010.Published September 2010.Originallyapproved in 1991.Last previous edition approved in 2004 as D4104 96(2004).DOI:10.1520/D4104-96R10E01.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandardsvolume 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 in a unit time under a unit hydraulic gradient through a unitarea measured at right angles to the direction of flow.3.1.6 observation wella well open to all or part of anaquifer.3.1.7 overdamped-well responsecharacterized by the wa-ter level returning to the static level in an approximatelyexponential manner following a sudden change in water level.(See for comparison underdamped-well response.)3.1.8 sluga volume of water or solid object used to inducea sudden change of head in a well.3.1.9 specific storagethe volume of water released fromor taken into storage per unit volume of the porous medium perunit change in head.3.1.10 storage coeffcientthe volume of water an aquiferreleases from or take