1、Designation: D4043 96 (Reapproved 2010)1Standard Guide forSelection of Aquifer Test Method in Determining HydraulicProperties by Well Techniques1This standard is issued under the fixed designation D4043; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he 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 1.2 was revised editorially in September 2010.1. Scope1.1 This guide
3、covers an integral part of a series ofstandards that are being prepared on the in situ determinationof hydraulic properties of aquifer systems by single- ormultiple-well tests. This guide provides guidance for develop-ment of a conceptual model of a field site and selection of ananalytical test meth
4、od for determination of hydraulic proper-ties. This guide does not establish a fixed procedure fordetermination of hydrologic properties.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 LimitationsWell techniques have lim
5、itations in thedetermination of hydraulic properties of ground-water flowsystems. These limitations are related primarily to the simpli-fying assumptions that are implicit in each test method. Theresponse of an aquifer system to stress is not unique; therefore,the system must be known sufficiently t
6、o select the properanalytical method.1.4 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 lim
7、itations prior to use.1.5 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 m
8、ay 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” i
9、n the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil, Rock, and ContainedFluidsD4044 Test Method for (Field Procedure) for InstantaneousChange in Head (Slug) Tests for
10、 Determining HydraulicProperties of AquifersD4050 Test Method for (Field Procedure) for Withdrawaland Injection Well Tests for Determining Hydraulic Prop-erties of Aquifer SystemsD4104 Test Method (Analytical Procedure) for DeterminingTransmissivity of Nonleaky Confined Aquifers by Over-damped Well
11、Response to Instantaneous Change in Head(Slug Tests)D4105 Test Method for (Analytical Procedure) for Deter-mining Transmissivity and Storage Coefficient of Non-leaky Confined Aquifers by the Modified Theis Nonequi-librium MethodD4106 Test Method for (Analytical Procedure) for Deter-mining Transmissi
12、vity and Storage Coefficient of Non-leaky Confined Aquifers by the Theis NonequilibriumMethodD4630 Test Method for Determining Transmissivity andStorage Coefficient of Low-Permeability Rocks by In SituMeasurements Using the Constant Head Injection TestD4631 Test Method for Determining Transmissivity
13、 andStorativity of Low Permeability Rocks by In Situ Mea-surements Using Pressure Pulse TechniqueD5269 Test Method for Determining Transmissivity ofNonleaky Confined Aquifers by the Theis RecoveryMethodD5270 Test Method for Determining Transmissivity and1This guide is under the jurisdiction ofASTM C
14、ommittee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current edition approved Aug. 1, 2010. Published September 2010. Originallyapproved in 1991. Last previous edition approved in 2004 as D404396(2004).DOI: 10.1520/D4043-9
15、6(2010)1.2For 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.1Copyright ASTM International, 100 Barr Harbor Drive
16、, PO Box C700, West Conshohocken, PA 19428-2959, United States.Storage Coefficient of Bounded, Nonleaky, ConfinedAqui-fersD5472 Test Method for Determining Specific Capacity andEstimating Transmissivity at the Control WellD5473 Test Method for (Analytical Procedure for) Analyz-ing the Effects of Par
17、tial Penetration of Control Well andDetermining the Horizontal and Vertical Hydraulic Con-ductivity in a Nonleaky Confined AquiferD5716 Test Method for Measuring the Rate of Well Dis-charge by Circular Orifice WeirD5785 Test Method for (Analytical Procedure) for Deter-mining Transmissivity of Confin
18、ed Nonleaky Aquifers byUnderdamped Well Response to Instantaneous Change inHead (Slug Test)D5786 Practice for (Field Procedure) for Constant Draw-down Tests in Flowing Wells for Determining HydraulicProperties of Aquifer SystemsD5850 Test Method for (Analytical Procedure) DeterminingTransmissivity,
19、Storage Coefficient, and Anisotropy Ratiofrom a Network of Partially Penetrating WellsD5881 Test Method for (Analytical Procedure) DeterminingTransmissivity of Confined Nonleaky Aquifers by Criti-cally Damped Well Response to Instantaneous Change inHead (Slug)D5912 Test Method for (Analytical Proced
20、ure) DeterminingHydraulic Conductivity of an Unconfined Aquifer byOverdamped Well Response to Instantaneous Change inHead (Slug)D5920 Test Method (Analytical Procedure) for Tests ofAnisotropic Unconfined Aquifers by Neuman Method3. Terminology3.1 Definitions:3.1.1 aquifer, confinedan aquifer bounded
21、 above andbelow by confining beds and in which the static head is abovethe top of the aquifer.3.1.2 aquifer, unconfinedan aquifer that has a water table.3.1.3 barometric effciencythe ratio of the change in depthto water in a well to the change in barometric pressure,expressed in length of water.3.1.
22、4 conceptual modela simplified representation of thehydrogeologic setting and the response of the flow system tostress.3.1.5 confining beda hydrogeologic unit of less perme-able material bounding one or more aquifers.3.1.6 control wellwell by which the aquifer is stressed, forexample, by pumping, in
23、jection, or change of head.3.1.7 hydraulic conductivity (field aquifer tests)the vol-ume of water at the existing kinematic viscosity that will movein a unit time under unit hydraulic gradient through a unit areameasured at right angles to the direction of flow.3.1.8 observation wella well open to a
24、ll or part of anaquifer.3.1.9 piezometera device used to measure static head at apoint in the subsurface.3.1.10 specific capacitythe rate of discharge from a welldivided by the drawdown of the water level within the well ata specific time since pumping started.3.1.11 specific storagethe volume of wa
25、ter released fromor taken into storage per unit volume of the porous medium perunit change in head.3.1.12 specific yieldthe ratio of the volume of water thatthe saturated rock or soil will yield by gravity to the volume ofthe rock or soil. In the field, specific yield is generallydetermined by tests
26、 of unconfined aquifers and represents thechange that occurs in the volume of water in storage per unitarea of unconfined aquifer as the result of a unit change inhead. Such a change in storage is produced by the draining orfilling of pore space and is, therefore, mainly dependent onparticle size, r
27、ate of change of the water table, and time ofdrainage.3.1.13 storage coeffcientthe volume of water an aquiferreleases from or takes into storage per unit surface area of theaquifer per unit change in head. For a confined aquifer, thestorage coefficient is equal to the product of specific storageand
28、aquifer thickness. For an unconfined aquifer, the storagecoefficient is approximately equal to the specific yield.3.1.14 transmissivitythe volume of water at the existingkinematic viscosity that will move in a unit time under a unithydraulic gradient through a unit width of the aquifer.3.2 For defin
29、itions of other terms used in this guide, seeTerminology D653.4. Significance and Use4.1 An aquifer test method is a controlled field experimentmade to determine the approximate hydraulic properties ofwater-bearing material. The hydraulic properties that can bedetermined are specific to the test met
30、hod. The hydraulicproperties that can be determined are also dependent upon theinstrumentation of the field test, the knowledge of the aquifersystem at the field site, and conformance of the hydrogeologicconditions at the field site to the assumptions of the testmethod. Hydraulic conductivity and st
31、orage coefficient of theaquifer are the basic properties determined by most testmethods. Test methods can be designed also to determinevertical and horizontal anisotropy, aquifer discontinuities, ver-tical hydraulic conductivity of confining beds, well efficiency,turbulent flow, and specific storage
32、 and vertical permeability ofconfining beds.5. Procedure5.1 The procedure for selection of an aquifer test method ormethods is primarily based on selection of a test method that iscompatible with the hydrogeology of the proposed test site.Secondarily, the test method is selected on the basis of thet
33、esting conditions specified by the test method, such as themethod of stressing or causing water-level changes in theaquifer and the requirements of a test method for observationsof water level response in the aquifer. The decision tree inTable 1 is designed to assist, first, in selecting test method
34、sapplicable to specific hydrogeologic site characteristics. Sec-ondly, the decision tree will assist in selecting a test method onthe basis of the nature of the stress on the aquifer imposed bythe control well. The decision tree references the sections inthis guide where the test methods are cited.5
35、.2 Pretest-Selection ProceduresAquifer test methods arehighly specific to the assumptions of the analytical solution ofD4043 96 (2010)12the test method. Reliability of determination of hydraulicproperties depends upon conformance of the hydrologic sitecharacteristics to the assumptions of the test m
36、ethod. Aprerequisite for selecting an aquifer test method is knowledgeof the hydrogeology of the test site. A conceptual understand-ing of the hydrogeology of the aquifer system at the prospec-tive test site should be gained in as much detail as possiblefrom existing literature and data, and a site
37、reconnaissance. InTABLE 1 Decision Tree for Selection of Aquifer Test MethodD4043 96 (2010)13developing a site characterization, incorporate geologic map-ping, drillers logs, geophysical logs, records of existing wells,water-level and water-quality data, and results of geophysicalsurveys. Include in
38、formation on the thickness, lithology, strati-fication, depth, attitude, continuity, and extent of the aquiferand confining beds.5.3 Select Applicable Aquifer Test MethodsSelect a testmethod based on conformation of the site hydrogeology toassumptions of the test model and the parameters to bedeterm
39、ined. A summary of principal aquifer test methods andtheir applicability to hydrogeologic site conditions is given inthe following paragraphs. The decision tree for aquifer testselection, Table 1, provides a graphic display of the hydrogeo-logic site conditions for each test method and references to
40、 thesection where each test method is cited.5.3.1 Extensive, Isotropic, Homogeneous, Confined, Non-leaky Aquifer:5.3.1.1 Constant DischargeTest method in which thedischarge or injection rate in the control well is constant aregiven by the nonequilibrium method of Theis (1)3for thedrawdown and recove
41、ry phases. The Theis test method is themost widely referenced and applied aquifer test method and isthe basis for the solution to other more complicated boundarycondition problems. The Theis test method for the pumping orinjection phase is given in Test Method D4106. Cooper andJacob (2) and Jacob (3
42、) recognized that for large values of timeand small values of distance from the control well, the Theissolution yields a straight line on semilogarithmic plots ofvarious combinations of drawdown and distance from thecontrol well. The solution of the Theis equation can thereforebe simplified by the u
43、se of semilogarithmic plots. The modifiedTheis nonequilibrium test method is given in Test MethodD4105. A test method for estimating transmissivity fromspecific capacity by the Theis method is given in Test MethodD5472.5.3.1.2 Variable DischargeTest methods for a variablydischarging control well hav
44、e been presented by Stallman (5)and Moench (6) and Birsoy and Summers (4). These testmethods simulate pumpage as a sequence of constant-ratestepped changes in discharge. The test methods utilize theprinciple of superposition in constructing type curves bysumming the effects of successive changes in
45、discharge. Thetype curves may be derived for control wells discharging fromextensive, leaky, and nonleaky confined aquifers or any situa-tion where the response to a unit stress is known. Hantush (7)developed drawdown functions for three types of decreases incontrol-well discharge. Abu-Zied and Scot
46、t (8) presented ageneral solution for drawdown in an extensive confined aquiferin which the discharge of the control well decreases at anexponential rate. Aron and Scott (9) proposed an approximatetest method of determining transmissivity and storage from anaquifer test in which discharge decreases
47、with time during theearly part of the test. Lai et al (10) presented test methods fordetermining the drawdown in an aquifer taking into accountstorage in the control well and having an exponentially andlinearly decreasing discharge.5.3.1.3 Constant DrawdownTest methods have been pre-sented to determ
48、ine hydraulic-head distribution around a dis-charging well in a confined aquifer with near constant draw-down. Such conditions are most commonly achieved byshutting in a flowing well long enough for the head to fullyrecover, then opening the well. The solutions of Jacob andLohman (11) and Hantush (7
49、) apply to aerially extensive,nonleaky aquifers. Rushton and Rathod (12) used a numericalmodel to analyze aquifer-test data. Reed (13) presents acomputer program that includes some of the above proceduresand also includes discharge as a fifth-degree polynomial oftime.5.3.1.4 Slug Test MethodsTest methods for estimatingtransmissivity by injecting a given quantity or slug of waterinto a well were introduced by Hvorslev (14) and Ferris andKnowles (15). Solutions to overdamped well response to slugtests have also been presented by Cooper et al (16). Theso
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