1、Designation: D7242/D7242M 06 (Reapproved 2013)1Standard Practice forField Pneumatic Slug (Instantaneous Change in Head) Teststo Determine Hydraulic Properties of Aquifers with DirectPush Groundwater Samplers1This standard is issued under the fixed designation D7242/D7242M; the number immediately fol
2、lowing 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.1NOTEDesignation was editor
3、ially corrected to match units information in December 2013.1. Scope*1.1 This standard practice covers the field methods used toconduct an instantaneous change in head (slug) test whenpneumatic pressure is used to initiate the change in headpressure within the well or piezometer. While this practice
4、specifically addresses use of pneumatic initiation of slug testswith direct push tools these procedures may be applied to wellsor piezometers installed with rotary drilling methods whenappropriate.1.2 This standard practice is used to obtain the required fielddata for determining hydraulic propertie
5、s of an aquifer or aspecified vertical interval of an aquifer. Field data obtainedfrom application of this practice are modeled with appropriateanalytical procedures (Test Methods D4104, D5785, D5881,D5912, Ref (1)2).1.3 The values stated in either SI units or inch-pound unitsare to be regarded sepa
6、rately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 This standard does not purport to address all of thesafety concern
7、s, 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.1.5 This practice offers a set of instructions for performingone or more specific ope
8、rations. This document cannot replaceeducation or experience and should be used in conjunctionwith professional judgment. Not all aspects of this practice maybe applicable in all circumstances. This ASTM standard is notintended to represent or replace the standard of care by whichthe adequacy of a g
9、iven professional service must be judged,nor should this document be applied without consideration ofa projects many unique aspects. The word “standard” in thetitle means that the document has been approved through theASTM consensus process.2. Referenced Documents2.1 ASTM Standards:3D653 Terminology
10、 Relating to Soil, Rock, and ContainedFluidsD2434 Test Method for Permeability of Granular Soils(Constant Head)D3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4104 Test Method (Analytical Procedur
11、e) for DeterminingTransmissivity of Nonleaky Confined Aquifers by Over-damped Well Response to Instantaneous Change in Head(Slug Tests)D5084 Test Methods for Measurement of Hydraulic Con-ductivity of Saturated Porous Materials Using a FlexibleWall PermeameterD5092 Practice for Design and Installatio
12、n of GroundwaterMonitoring WellsD5521 Guide for Development of Groundwater MonitoringWells in Granular AquifersD5785 Test Method for (Analytical Procedure) for Deter-mining Transmissivity of Confined Nonleaky Aquifers byUnderdamped Well Response to Instantaneous Change inHead (Slug Test)D5856 Test M
13、ethod for Measurement of Hydraulic Conduc-tivity of Porous Material Using a Rigid-Wall,Compaction-Mold Permeameter1This 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.Curren
14、t edition approved Dec. 1, 2013. Published January 2014. Originallyapproved in 2006. Last previous edition approved in 2006 as D7242 06. DOI:10.1520/D7242-06R13.2The boldface numbers in parentheses refer to the list of references at the end ofthis standard.3For referenced ASTM standards, visit the A
15、STM 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
16、Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D5881 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 Procedure) Determ
17、iningHydraulic Conductivity of an Unconfined Aquifer byOverdamped Well Response to Instantaneous Change inHead (Slug) (Withdrawn 2013)4D6001 Guide for Direct-Push Groundwater Sampling forEnvironmental Site CharacterizationD6282 Guide for Direct Push Soil Sampling for Environ-mental Site Characteriza
18、tions (Withdrawn 2014)4D6724 Guide for Installation of Direct Push GroundwaterMonitoring WellsD6725 Practice for Direct Push Installation of PrepackedScreen Monitoring Wells in Unconsolidated Aquifers3. Terminology3.1 Terminology used within this practice is in accordancewith Terminology D653 with t
19、he addition of the following:3.2 Definitions:3.2.1 direct-push (DP) samplingsampling devices that aredirectly inserted into the soil without drilling or boreholeexcavation. D60013.2.2 two-tube systema system whereby inner and outertubes are advanced simultaneously into the subsurface strata tocollec
20、t a soil sample, sometimes referred to as dual-tube. Theouter tube is used for borehole stabilization. The inner tube forsampler insertion and recovery. D62823.2.3 single-tube systema system whereby singleextension/drive rods with samplers attached are advanced intothe subsurface strata to collect a
21、 soil sample. D62823.2.4 slug testa single well test to measure aquifer prop-erties such as transmissivity and hydraulic conductivity. A slugtest is conducted by inducing a near instantaneous change inthe static water level in a well and observing the recovery ofthe water level to static condition o
22、ver time. Also called aninstantaneous change in head test.4. Summary of Practice4.1 This practice describes the field procedures used toconduct an instantaneous change in head (slug) test in a directpush (DP) installed groundwater sampling device or monitor-ing well using air pressure to cause a sud
23、den change in thewater level. A pneumatic manifold is installed on a developedwell or DP installed device to control the pressure in thewellhead. Positive pressure or vacuum may be applied with thepneumatic manifold to induce a rising head test or falling headtest, respectively. The changing water l
24、evel in the well ismonitored with a transducer and data acquisition device andthe data is saved for curve fitting and analysis.4.2 Appropriate well design and construction is necessary toobtain representative slug test results. Furthermore, withoutadequate development (Practice D6725, Guide D5521, R
25、efs (1,2) of the well or groundwater sampling device slug tests mayyield biased data. Field quality control may be monitored byconducting replicate tests after development and visuallycomparing the replicate data sets.4.3 Aquifer response data obtained from the pneumatic slugtests are modeled with t
26、he appropriate analysis method (TestMethods D4104, D5785, D5881, D5912, Refs (1, 3)tocalculate the transmissivity and/or hydraulic conductivity ofthe screened formation.5. Significance and Use5.1 Combining slug test methods with the use of direct pushinstalled groundwater sampling devices provides a
27、 time andcost-effective method that was previously not available forevaluating spatial variations of hydraulic conductivity (K) inunconsolidated aquifers. Current research (Ref (4) has foundthat small (decimeter) scale variations in hydraulic conductiv-ity may have significant influence on solute tr
28、ansport andtherefore design of groundwater remediation systems. Otherinvestigators (Ref (5) report that spatial variation in K isbelieved to be the main source of uncertainty in the predictionof contaminant transport in aquifers. They found that increas-ing the data density for K in model input noti
29、ceably reducedthe uncertainty of model prediction. Because of increasedefficiency and reduced costs, the combination of slug testmethods with DP groundwater sampling devices makes itpossible to obtain the additional information required to reduceuncertainty in contaminant transport models and improv
30、eremedial action design.5.2 The data obtained from application of this practice maybe modeled with the appropriate analytical method to provideinformation on the transmissivity and hydraulic conductivity ofthe screened formation in a timely and cost effective manner.5.3 The appropriate analytical me
31、thod selected for analysisof the data will depend on several factors, including, but notlimited to, the aquifer type (confined, unconfined, leaky) wellconstruction parameters (partially or fully penetrating), and thetype of aquifer response observed during the slug test (over-damped or underdamped).
32、 Some of the appropriate methodsmay include Test Methods D4104, D5785, D5881 and D5912.A thorough review of many slug test models and analyticalmethods is provided in Ref (1).5.4 Slug tests may be conducted in materials of lowerhydraulic conductivity than are suitable for pumping tests. Slugtests ma
33、y be used to obtain estimates of K for aquitardsconsisting primarily of silts and clays. Special field proceduresmay be required.5.5 The pneumatic slug test provides some advantages whencompared to pumping tests or slug tests conducted by othermethods.5.5.1 Some of the advantages relative to pump te
34、sts include:5.5.1.1 No water added to or removed from the well. Animportant consideration when water quality must not be alteredfor purposes of environmental sampling.4The last approved version of this historical standard is referenced onwww.astm.org.D7242/D7242M 06 (2013)125.5.1.2 Large volumes of
35、water not removed from the wellas during a pumping test. An important consideration if thegroundwater is contaminated and will require disposal as aregulated waste.5.5.1.3 Slug tests usually require only a fraction of the timeneeded to complete a pump test.5.5.1.4 No large diameter pumping well or d
36、own well pumprequired.5.5.1.5 Slug tests provide information on K for the forma-tion in the vicinity of the well.5.5.2 Some advantages relative to slug tests using water ora mechanical slug include:5.5.2.1 No water added to or removed from the well or DPsampler to conduct the test. Generally does no
37、t change waterquality for sampling. Use of vacuum to induce a falling headtest could result in loss of volatiles from water in the wellcolumn. Additional purging may be required before samplingfor volatile contaminants.5.5.2.2 Pneumatic initiation of the slug test provides clean,high quality data wi
38、th minimal noise, especially important inhigh hydraulic conductivity formations and small diameterwells.5.5.2.3 In small diameter DP tools, inserting a mechanicalslug or adding water may be difficult or even preclude accuratemeasurement of changing water levels.5.5.3 Some disadvantages of slug tests
39、 as compared topumping tests include:5.5.3.1 Slug tests provide information on K for the forma-tion only in the vicinity of the well, not a large scale averagevalue as obtained from a pumping test.5.5.3.2 Most slug test analytical methods can provide infor-mation only on aquifer transmissivity and h
40、ydraulic conduc-tivity. Pumping test analysis can provide additional informa-tion on aquifer parameters such as specific storage, etc.5.5.4 Some disadvantages of the pneumatic slug test relativeto slug tests using water or a mechanical slug include:5.5.4.1 Airtight seals needed on the well casing or
41、 driverods.5.5.4.2 The screen must remain below the water levelthroughout the slug test. Wells screened across the water tablecannot be slug tested with the pneumatic method.5.5.4.3 Pressure transducers and electronic acquisitionmethods usually required for pneumatic slug testing. Notalways needed f
42、or manual methods.5.5.4.4 Equilibration of water level after pressure (orvacuum) applied to the wellhead increases time required tocomplete the slug test, especially important in low-K forma-tions.5.6 Direct push methods provide some advantages as com-pared to conventional drilling methods for the i
43、nstallation ofwells and temporary groundwater monitoring devices to beused for slug testing. Some of the advantages include:5.6.1 DP methods minimize generation of soil cuttingsreducing waste handling and disposal costs at contaminatedsites during the installation of permanent wells (Guide D6724,Pra
44、ctice D6725) and temporary groundwater monitoring de-vices (Guide D6001).5.6.2 Several types of temporary groundwater monitoringdevices may be installed by DPmethods (Guide D6001). Thesetools may be installed at various depths and various locationsfor slug testing and groundwater sampling in unconso
45、lidatedmaterials. Most of these tools are extracted for decontamina-tion and multiple re-use, and can minimize the need forpermanent well installations.5.6.3 Short screens may be used to slug test discrete depthintervals to document vertical and lateral variations of K withinan aquifer in a cost and
46、 time effective manner.5.6.4 Equipment required to install DP wells and temporarygroundwater samplers are often smaller and more mobile thanconventional rotary drilling equipment. This can make siteaccess easier and more rapid.5.6.5 Other direct push screening and sampling methods, forexample Guide
47、D6282 on soil sampling, can be used to detecttest zones in advance of slug testing, which helps withknowledge of test location.5.6.6 Direct push tests are minimally intrusive.5.6.7 Direct push tests are generally more rapid and lessexpensive than other drilling methods.5.7 Some disadvantages of DP m
48、ethods as compared toconventional rotary drilling include:5.7.1 DP methods generally provide a smaller diameter borehole than traditional rotary drilling. This may limit the size ofequipment than can be placed down hole.5.7.2 Direct push tools are designed to penetrate unconsoli-dated materials only
49、. Other rotary drilling methods will berequired to penetrate consolidated rock.5.7.3 Some subsurface conditions may limit the depth ofpenetration of DP methods and tools. Some examples includethick caliche layers, cobbles or boulders, or very densematerials, such as high density glacial tills.NOTE 1The quality of the result produced by this standard isdependent on the competence of the personnel performing it, and thesuitability of the equipment and facilities used. Agencies that meet thecriteria of Practice D3740 are generally considered capable of competentand object
