1、Designation: D 4044 96 (Reapproved 2002)Standard Test Method(Field Procedure) for Instantaneous Change in Head (Slug)Tests for Determining Hydraulic Properties of Aquifiers1This standard is issued under the fixed designation D 4044; the number immediately following the designation indicates the year
2、 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the field procedure for perform
3、-ing an in situ instantaneous change in head (slug) test.1.2 This test method is used in conjunction with an analyti-cal procedure such as Test Method D 4104 to determine aquiferproperties.1.3 The values stated in the SI units are to be regarded asstandard.1.4 This standard does not purport to addre
4、ss 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:D 653 Terminolog
5、y Relating to Soil, Rock, and ContainedFluids2D 4043 Guide for Selection of Aquifer-Test Method inDetermination of Hydraulic Properties by Well Tech-niques2D 4104 Test Method (Analytical Procedure) for Determin-ing Transmissivity of Confined Nonleaky Aquifers byOverdamped Well Response to Instantane
6、ous Change inHead (Slug Test)2D 4750 Test Method for Determining Subsurface LiquidLevels in a Borehole or Monitoring Well (ObservationWell)2D 5785 Test Method for (Analytical Procedure) for Deter-mining Transmissivity of Confined Nonleaky Aquifers byUnderdamped Well Response to Instantaneous Change
7、InHead (Slug Test)3D 5881 Test Method (Analytical Procedure) for Determin-ing Transmissivity of Confined Nonleaky Aquifers byCritically Damped Well Response to InstantaneousChange In Head (Slug Test)3D 5912 Test Method (Analytical Procedure) for Determin-ing Hydraulic Conductivity of an Unconfined A
8、quifer byOverdamped Well Response to Instantaneous Change InHead (Slug Test)33. Terminology3.1 Definitions: Definitions:3.1.1 control wellwell by which the aquifer is stressed, forexample, by pumping, injection, or change of head.3.1.2 hydraulic conductivity(field aquifer tests), the vol-ume of wate
9、r at the existing kinematic viscosity that will movein a unit time under a unit hydraulic gradient through a unitarea measured at right angles to the direction of flow.3.1.3 observation wella well open to all or part of anaquifer.3.1.4 overdamped-well responsecharacterized by the wa-ter level return
10、ing to the static level in an approximatelyexponential manner following a sudden change in water level.(See for comparison underdamped well.)3.1.5 sluga volume of water or solid object used to inducea sudden change of head in a well.3.1.6 storage coeffcientthe volume of water an aquiferreleases from
11、 or takes into storage per unit surface area of theaquifer per unit change in head. For a confined aquifer, it isequal to the product of specific storage and aquifer thickness.For an unconfined aquifer, the storage coefficient is approxi-mately equal to the specific yield.3.1.7 transmissivitythe vol
12、ume of water at the existingkinematic viscosity that will move in a unit time under a unithydraulic gradient through a unit width of the aquifer.3.1.8 underdamped-well responsecharacterized by thewater level oscillating about the static water level following asudden change in water level. (See for c
13、omparison overdampedwell.)3.1.9 For definitions of other terms used in this test method,refer to Terminology D 653.4. Summary of Test Method4.1 This test method describes the field procedures involvedin conducting an instantaneous head (slug) test. The slug testmethod involves causing a sudden chang
14、e in head in a controlwell and measuring the water level response within that controlwell. Head change may be induced by suddenly injecting or1This test method is under the jurisdiction of ASTM Committee D18 on Soil andRock and is the direct responsibility of Subcommittee D18.21 on Ground Water andV
15、adose Zone Investigations.Current edition approved Oct. 10, 1997. Published February 1997. Originallypublished as D 4044 91. Last previous edition D 4044 91.2Annual Book of ASTM Standards, Vol 04.08.3Annual Book of ASTM Standards, Vol 04.091Copyright ASTM International, 100 Barr Harbor Drive, PO Box
16、 C700, West Conshohocken, PA 19428-2959, United States.removing a known quantity or “slug” of water into the well,rapid removal of a mechanical “slug” from below the waterlevel, increasing or decreasing the air pressure in the wellcasing, or emplacement of a mechanical slug into the watercolumn.4.2
17、The water-level response in the well is a function of themass of water in the well and the transmissivity and coefficientof storage of the aquifer. One method of analysis of the datafrom this field practice is described in Test Method D 4104.5. Significance and Use5.1 This slug test field procedure
18、is used in conjunction witha slug test analytical procedure, such as Test Method D 4104 toprovide quick and relatively inexpensive estimates of transmis-sivity.5.2 The slug test provides an advantage over pumping testsin that it does not require the disposal of the large quantities ofwater that may
19、be produced. This is of special importancewhen testing a potentially contaminated aquifer. However, slugtests reflect conditions near the well, therefore are influencedby near-well conditions, such as gravel pack, poor welldevelopment, and skin effects.5.3 Slug tests may be made in aquifer materials
20、 of lowerhydraulic conductivity than generally considered suitable forhydraulic testing with pumping tests.5.4 The method of data analysis (analytical procedure)should be known prior to the field testing to ensure that allappropriate dimensions and measurements are properly re-corded. Selection of t
21、he analytical procedure can be aided byusing Guide D 4043, Test Method D 5785, Test MethodD 5881, and Test Method D 5912.6. Apparatus6.1 Slug-Inducing EquipmentThis test method describesthe types of equipment that can be used. Because of the infinitevariety of testing conditions and because similar
22、results can beachieved with different apparatus, engineering specificationsfor apparatus are not appropriate. This test method specifies theresults to be achieved by the equipment to satisfy the require-ments of this practice.6.2 Water-Level Measurement EquipmentThe method ofwater level measurement
23、may be dependent on the methodselected for injection or withdrawal of water, and the nature ofthe response of the well. For an open-well test, that is, whereaccess to the water level is open to the surface, measure waterlevels manually as described in Test Method D 4750, by anautomatic recording dev
24、ice linked to a float, or with a pressuretransducer linked to a data logger or display device. A pressuretransducer linked to a data logger will be necessary for a test ina closed well in which water-level changes are induced byvacuum or pressure on the control well and where manualmeasurements do n
25、ot provide measurements of adequate fre-quency (see 9.3).7. Conditioning7.1 Pre-Test Procedure:7.1.1 Measuring Pre-Test Water LevelsMeasure the waterlevel in the control well before beginning the test for a periodlonger than the duration of the test to determine the pre-testwater level fluctuations
26、and to establish pre-pumping water-level trend and to determine a pre-pumping reference waterlevel.8. Procedure8.1 Cause a change in water level, either a rise or decline, byone of the following methods:8.1.1 Water SlugInject or withdraw water of a knownquantity into or from the control well.8.1.2 M
27、echanical SlugInject or withdraw a mechanicalslug below or above the water level. The water within thecontrol well will then rise or decline an amount equal to thevolume of the mechanical slug.8.1.3 Release Vacuum or PressureA method of simulatingthe injection or withdrawal of a slug of water is by
28、the releaseof a vacuum or pressure on a tightly capped (shut-in) controlwell. Before the release, the vacuum or pressure is heldconstant.NOTE 1There is no fixed requirement for the magnitude of the changein water level. Similar results can be achieved with a wide range ininduced head change. Some co
29、nsiderations include a magnitude of changethat can be readily measured with the apparatus selected, for example thehead change should be such that the method of measurement should beaccurate to1%ofthemaximum head change. Generally, an induced headchange of from one-third to one meter is adequate. Al
30、though the inducedhead change should be sufficient to allow the response curve to be defined,excessive head change should be avoided to reduce the possibility ofintroducing large frictional losses in well bore.The mechanical model for the test assumes the head change is inducedinstantaneously. Pract
31、ically, a finite time is required to effect a headchange. Selection of time zero can be selected experimentally. Refer to themethod of analysis (such as Test Method D 4104) to determine time zeroand to evaluate the suitability of the change effected in the well.8.2 Measure water-level response to th
32、e change in waterlevel. The frequency of water-level measurement during thetest is dependent upon the hydraulic conductivity of thematerial being tested. During the early portions of the test,measure water levels at closely-spaced intervals. Measure-ments of water level made manually with a tape sho
33、uld bemade as frequently as possible until the water level hasrecovered about 60 to 80 %. Increase the length of timebetween measurements with increasing duration of the test.Since most methods of data analysis are curve-fitting tech-niques, it is essential that water levels are measured frequentlye
34、nough to define the water-level response curve (see GuideD 4043, Test Methods D 4104 and D 5785).8.2.1 In aquifer-well systems where water-level changes arerapid, it may be necessary to use a pressure transducer linkedto an electronic data logger to measure and record the waterlevels frequently enou
35、gh to adequately define the waterlevelresponse. The use of transducers and data loggers generallyprovides a greater than adequate frequency of measurements,ranging from several measurements per second in the early partof the test to a specified frequency in the later portions of a test.With such equ
36、ipment, the test analysis may use a reduced dataset of measurements to calculate the hydraulic properties (seeGuide D 4043, Test Methods D 4104 and D 5785 for analysisof water level data).8.3 Post-Test ProcedureMake preliminary analysis ofdata before leaving the field and evaluate the test regarding
37、 theD 40442criteria given in this test method and the method of analysis,such as Test Method D 4104 to determine if the test should bererun.9. Report9.1 Include the information listed below in the report of thefield procedure:9.2 All test reports should include the following:9.2.1 Date, time, and we
38、ll identification,9.2.2 Method of slug withdrawal or injection, as well aswhether the test is a falling head (injection) or a rising head(withdrawal) test,9.2.3 Inside diameter of well screen and well casing abovescreen,9.2.4 Depth of well,9.2.5 Length and depth setting of screen,9.2.6 Volume of mec
39、hanical slug or pressure change im-posed on water level, and9.2.7 Pre-testing water-level trend.9.3 Establish and record the measurement point from whichall measurements of water level are made. Record date, time,and depth to water level below measurement point of all waterlevels.9.4 Water levels me
40、asured during the test should be re-corded with information on date, clock time, and time since teststarted. If the water levels are measured with a pressuretransducer and recorded with an electronic data logger, recordthe name of the data file on the data logger.10. Precision and Bias10.1 It is not
41、 practical to specify the precision of this testmethod because the response of aquifer systems during aquifertests is dependent upon ambient system stresses. No statementcan be made about bias because no true reference values exist.11. Keywords11.1 aquifers; aquifer tests; ground water; hydraulic co
42、nduc-tivity; hydraulic properties; instantaneous head test; slug tests;storage coefficient; transmissivityASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised tha
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45、el that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 40443
