1、Designation: D 5781 95 (Reapproved 2006)Standard Guide forUse of Dual-Wall Reverse-Circulation Drilling forGeoenvironmental Exploration and the Installation ofSubsurface Water-Quality Monitoring Devices1This standard is issued under the fixed designation D 5781; the number immediately following the
2、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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers how dua
3、l-wall reverse-circulationdrilling may be used for geoenvironmental exploration andinstallation of subsurface water-quality monitoring devices.NOTE 1The term reverse circulation with respect to dual-wall drillingin this guide indicates that the circulating fluid is forced down the annularspace betwe
4、en the double-wall drill pipe and transports soil and rockparticles to the surface through the inner pipe.NOTE 2This guide does not include considerations for geotechnicalsite characterizations that are addressed in a separate guide.1.2 Dual-wall reverse-circulation for geoenvironmental ex-ploration
5、 and monitoring-device installations will often in-volve safety planning, administration, and documentation. Thisguide does not purport to specifically address exploration andsite safety.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for info
6、rmationonly.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 limitations prior to use.1.5
7、 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 may be applicable in allci
8、rcumstances. 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” in the title of thisdocume
9、nt means only that the document has been approvedthrough the ASTM consensus process.2. Referenced Documents2.1 ASTM Standards:2D 653 Terminology Relating to Soil, Rock, and ContainedFluidsD 1452 Practice for Soil Investigation and Sampling byAuger BoringsD 1586 Test Method for Penetration Test and S
10、plit-BarrelSampling of SoilsD 1587 Practice for Thin-Walled Tube Sampling of Soilsfor Geotechnical PurposesD 2487 Practice for Classification of Soils for EngineeringPurposes (Unified Soil Classification System)D 3550 Practice for Thick Wall, Ring-Lined, Split Barrel,Drive Sampling of SoilsD 4428/D
11、4428M Test Methods for Crosshole Seismic Test-ingD 5088 Practices for Decontamination of Field EquipmentUsed at Waste SitesD 5092 Practice for Design and Installation of GroundWater Monitoring WellsD 5099 Test Methods for RubberMeasurement of Pro-cessing Properties Using Capillary RheometryD 5254 Pr
12、actice for Minimum Set of Data Elements toIdentify a Ground-Water SiteD 5434 Guide for Field Logging of Subsurface Explora-tions of Soil and Rock3. Terminology3.1 Definitions:3.1.1 Terminology used within this guide is in accordancewith Terminology D 653. Definitions of additional terms maybe found
13、in Terminology D 653.1This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current edition approved July 1, 2006. Published August 2006. Originallyapproved in 1995. Last previou
14、s edition approved in 2000 as D 5781 95 (2000).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 AST
15、M International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 Definitions of Terms Specific to This Standard:3.2.1 bentonitecommon name for drilling-fluid additivesand well-construction products consisting mostly of naturally-occurring montmorillonite. Some
16、 bentonite products havechemical additives that may affect water-quality analyses.3.2.2 bentonite granules and chipsirregularly-shaped par-ticles of bentonite (free from additives) that have been driedand separated into a specific size range.3.2.3 bentonite pelletsroughly spherical- or disc-shapedun
17、its of compressed bentonite powder (some pellet manufac-turers coat the bentonite with chemicals that may affect thewater quality analysis).3.2.4 coeffcient of uniformityCu(D), the ratio D60/D10,where D60is the particle diameter corresponding to 60 % fineron the cumulative particle-size distribution
18、 curve, and D10isthe particle diameter corresponding to 10 % finer on thecumulative particle-size distribution curve.3.2.5 drawworksa power-driven winch, or severalwinches, usually equipped with a clutch and brake system(s)for hoisting or lowering a drilling string.3.2.6 drill holea cylindrical hole
19、 advanced into the sub-surface by mechanical means. Also known as a borehole orboring.3.2.7 filter packalso known as a gravel pack or a primaryfilter pack in the practice of monitoring-well installations. Thegravel pack is usually granular material, having selected grainsize characteristics, that is
20、 placed between a monitoring deviceand the borehole wall. The basic purpose of the filter pack orgravel envelope is to act as: (1) a non-clogging filter when theaquifer is not suited to natural development or, (2) act as aformation stabilizer when the aquifer is suitable for naturaldevelopment.3.2.7
21、.1 DiscussionUnder most circumstances a clean,quartz sand or gravel should be used. In some cases apre-packed screen may be used.3.2.8 hoisting lineor drilling line, is wire rope used on thedrawworks to hoist and lower the drill string.3.2.9 in-situ testing devicessensors or probes, used forobtainin
22、g mechanical or chemical-test data, that are typicallypushed, rotated or driven below the bottom of a boreholefollowing completion of an increment of drilling. However,some in-situ testing devices (such as electronic pressuretransducers, gas-lift samplers, tensiometers, and etc.) mayrequire lowering
23、 and setting of the device(s) in a pre-existingborehole by means of a suspension line or a string of loweringrods or pipe. Centralizers may be required to correctly positionthe device(s) in the borehole.3.2.10 intermittent-sampling devicesusually barrel-typesamplers that are driven or pushed below t
24、he bottom of aborehole following completion of an increment of drilling. Theuser is referred to the following ASTM Standards relating tosuggested sampling methods and procedures: Practice D 1452,Test Method D 1586, Practice D 3550, and Practice D 1587.3.2.11 mastor derrick, on a drilling rig is used
25、 forsupporting the crown block, top drive, pulldown chains,hoisting lines, etc. It must be constructed to safely carry theexpected loads encountered in drilling and completion of wellsof the diameter and depth for which the rig manufacturerspecifies the equipment.3.2.11.1 DiscussionTo allow for cont
26、ingencies, it is rec-ommended that the rated capacity of the mast should be at leasttwice the anticipated weight load or normal pulling load.3.2.12 piezometeran instrument for measuring pressurehead.3.2.13 subsurface water-quality monitoring devicean in-strument placed below ground surface to obtain
27、 a sample foranalysis of the chemical, biological or radiological character-istics of subsurface-pore water or to make in-situ measure-ments.4. Significance and Use4.1 Dual-wall reverse-circulation drilling can be used insupport of geoenvironmental exploration and for installation ofsubsurface water
28、-quality monitoring devices in unconsolidatedand consolidated materials. Dual-wall reverse-circulation drill-ing methods permit the collection of water-quality samples atany depth(s), allows the setting of temporary casing duringdrilling, cuttings samples can be taken continuously as circu-lation is
29、 maintained at all times during drilling. Other advan-tages of the dual-wall reverse-circulation drilling methodinclude: (1) the capability of drilling without the introductionof any drilling fluid(s) to the subsurface; (2) maintenance ofhole stability for sampling purposes and monitor-wellinstallat
30、ion/construction in poorly-indurated to unconsolidatedmaterials.NOTE 3The user of dual-wall reverse-circulation drilling for geoen-vironmental exploration and monitoring-device installations should becognizant of both the physical (temperature and airborne particles) andchemical (compressor lubrican
31、ts and possible fluid additives) qualities ofcompressed air that may be used as the circulating medium.4.2 The application of dual-wall reverse-circulation drillingto geoenvironmental exploration may involve soil or rocksampling, or in-situ soil, rock, or pore-fluid testing.NOTE 4The user may instal
32、l a monitoring device within the sameborehole wherein sampling, in-situ or pore-fluid testing, or coring wasperformed.4.3 The subsurface water-quality monitoring devices thatare addressed in this guide consist generally of a screened- orporous-intake device and riser pipe(s) that are usually install
33、edwith a filter pack to enhance the longevity of the intake unit,and with isolation seals and low-permeability backfill to deterthe movement of fluids or infiltration of surface water betweenhydrologic units penetrated by the borehole (see PracticeD 5092). Inasmuch as a piezometer is primarily a dev
34、ice usedfor measuring subsurface hydraulic heads, the conversion of apiezometer to a water-quality monitoring device should bemade only after consideration of the overall quality andintegrity of the installation to include the quality of materialsthat will contact sampled water or gas.NOTE 5Both wat
35、er-quality monitoring devices and piezometersshould have adequate casing seals, annular isolation seals and backfills todeter communication of contaminants between hydrologic units.D 5781 95 (2006)25. Apparatus5.1 The basic mechanical components of dual-wall reverse-circulation drilling systems incl
36、ude dual-wall pipe, drill com-pressor and filter(s), water pump, discharge hose, cleaningdevice (cyclone separator). The dual-wall drill advanced by thepercussive action of an above-ground pile hammer or byrotation from a rotary-drive unit.NOTE 6Other methods, such as vibratory equipment sonic reson
37、ators,may be used to apply the energy required to advance the dual-wall drillpipe.5.1.1 dual-wall drill pipe, consists of an inner pipe securedconcentrically within an outer pipe. Inner-pipe connectionsutilize pin and box components with seals. Outer-pipe connec-tions are flush threaded.NOTE 7Drill
38、pipes usually require lubricants on the threads to alloweasy unthreading (breaking) of the connecting joints. Some lubricantshave organic or metallic constituents, or both, that could be interpreted ascontaminants if detected in a sample. Various lubricants are available thathave components of known
39、 chemistry. The effect of pipe-thread lubricantson chemical analyses of samples should be considered and documentedwhen using dual-wall reverse-circulation drilling. The same considerationand documentation should be given to lubricants used with water swivels,hoisting swivels, or other devices used
40、near the drilling axis.5.1.2 The drill bit is attached to the bottom of the dual-walldrill pipe and provides the soil- or rock-cutting capability. Drillbit types include tricone roller, down-the-hole (DTH) hammeror, open faced. Drill bit selection should be based upon thecharacter of the soils or ro
41、cks penetrated. DTH lubricantsshould be documented.NOTE 8In NorthAmerica, the sizes of casings bits, drill rods and corebarrels are standardized by American Petroleum Institute (API) and theDiamond Core Drill Manufacturers Association (DCDMA). Refer to theDCDMA technical manual and to published mate
42、rials of API for availablesizes and capacities of drilling tools equipment.5.1.3 The air compressor and filter(s) should provide anadequate volume of air for removal of cuttings withoutsignificant contamination generated at the bit.Air requirementswill vary depending upon the size and configuration
43、of the drillpipe used, and the character of the soil and rock penetrated.The air-flow rates are usually based on maintaining an upflowair velocity of about 1400 m/min (4200 ft/min).NOTE 9The quality of compressed air entering the borehole and thequality of air discharged from the borehole and air-cl
44、eaning devices mustbe considered. If not adequately filtered, the air produced by mostoil-lubricated air compressors inherently introduces a significant quantityof oil into the circulation system. High-efficiency, in-line, air filters areusually required to prevent significant contamination of the b
45、orehole.Air-quality monitoring may be required and, if performed, results shouldbe documented.5.1.4 A water pump may be used to inject water into thecirculating air stream or may be used to inject water without airas the circulating fluid. If water is injected, the approximatevolumes and locations s
46、hould be reported.5.1.5 A discharge hose conducts discharged drill cuttingsand circulation-return air away from the borehole.5.1.6 Air-Cleaning Device System, generally called a cy-clone separator, separates cuttings from the air returning fromthe borehole.NOTE 10A properly-sized cyclone separator c
47、an remove practicallyall of the cuttings from the return air. A small quantity of fine particles,however, are usually discharged to the atmosphere with the “cleaned” air.Some air-cleaning devices consist of a cyclone separator alone. In specialcases, the cyclone separator can be combined with a HEPA
48、 (high-efficiency particulate air) filter for removing dust particles that might beradioactive. In other special situations, the cyclone separator may be usedin conjunction with a charcoal-filtering arrangement for removal oforganic volatiles. Samples of drill cuttings can be collected for analyses
49、ofmaterials penetrated. If samples are obtained, the depth(s) and interval(s)of sample collection should be documented.5.1.7 Pile Hammer, is commonly used to advance dual-walldrill pipe. The percussive force of the pile hammer is appliedonly to the outer pipe.5.1.8 Rotary-Drive Unit, may be used to advance dual-walldrill pipe by rotation. Torque generated from a rotary-drive unitis applied only to the outer pipe.6. Drilling Procedures6.1 Dual-Wall Percussion-Hammer Method (see Fig. 1):FIG. 1 Drilling with the Dual Wall Percussion Hammer MethodD 5781 95 (
