1、Designation: D 5299 99 (Reapproved 2005)Standard Guide forDecommissioning of Ground Water Wells, Vadose ZoneMonitoring Devices, Boreholes, and Other Devices forEnvironmental Activities1This standard is issued under the fixed designation D 5299; the number immediately following the designation indica
2、tes 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 procedures that are speci
3、fically re-lated to permanent decommissioning (closure) of the followingas applied to environmental activities. It is intended for usewhere solid or hazardous materials or wastes are found, orwhere conditions occur requiring the need for decommission-ing. The following devices are considered in this
4、 guide:1.1.1 A borehole used for geoenvironmental purposes (seeNote 1),1.1.2 Monitoring wells,1.1.3 Observation wells,1.1.4 Injection wells (see Note 2),1.1.5 Piezometers,1.1.6 Wells used for the extraction of contaminated groundwater, the removal of floating or submerged materials otherthan water s
5、uch as gasoline or tetrachloroethylene, or otherdevices used for the extraction of soil gas,1.1.7 A borehole used to construct a monitoring well, and1.1.8 Any other vadose zone monitoring device.1.2 Temporary decommissioning of the above is not cov-ered in this guide.NOTE 1This guide may be used to
6、decommission boreholes where nocontamination is observed at a site (see Practice D 420 for details);however, the primary use of the guide is to decommission boreholes andwells where solid or hazardous waste have been identified. Methodsidentified in this guide can also be used in other situations su
7、ch as thedecommissioning of water supply wells and boreholes where watercontaminated with nonhazardous pollutants (such as nitrates or sulfates)are present. This guide should be consulted in the event that a routinegeotechnical investigation indicates the presence of contamination at asite.NOTE 2The
8、 term “well” is used in this guide to denote monitoringwells, piezometers, or other devices constructed in a manner similar to awell. Some of the devices listed such as injection and extraction wells canbe decommissioned using this guide for information, but are not specifi-cally covered in the text
9、.NOTE 3Details on the decommissioning of multiple-screened wellsare not provided in this guide due to the many methods used to constructthese types of wells and the numerous types of commercially availablemultiple-screened well systems. However, in some instances, the methodspresented in this guide
10、may be used with few changes.An example of howthis guide may be used is the complete removal of the multiple-screenedwells by overdrilling.1.3 Most monitoring wells and piezometers are intendedprimarily for water quality sampling, water level observation,or soil gas sampling, or combination thereof,
11、 to determinequality. Many wells are relatively small in diameter and areused to monitor for hazardous chemicals in ground water.Decommissioning of monitoring wells is necessary to:1.3.1 Eliminate the possibility that the well is used forpurposes other than intended,1.3.2 Prevent migration of contam
12、inants into an aquifer orbetween aquifers,1.3.3 Prevent migration of contaminants in the vadose zone,1.3.4 Reduce the potential for vertical or horizontal migra-tion of fluids in the well or adjacent to the well, and1.3.5 Remove the well from active use when the well is nolonger capable of rehabilit
13、ation, or has failed structurally; nolonger required for monitoring; no longer capable of providingrepresentative samples or is providing unreliable samples; orrequired to be decommissioned; or to meet regulatory require-ments.NOTE 4The determination of whether a well is providing a represen-tative
14、water quality sample is not defined in this guide. Examples of whena representative water quality sample may not be collected include thebiological or chemical clogging of well screens, a drop in water level tobelow the base of the well screen, or complete silting of a tail pipe. Theseconditions may
15、 indicate that a well is not functioning properly.1.4 This guide is intended to provide information for effec-tive permanent closure of wells so that the physical structure ofthe well does not provide a means of hydraulic communicationbetween aquifers or react chemically in a detrimental way withthe
16、 environment.1.5 The intent of this guide is to provide procedures thatwhen followed result in a reasonable level of confidence in theintegrity of the decommissioning activity. However, it may notbe possible to verify the integrity of the decommissioning1This guide is under the jurisdiction ofASTM C
17、ommittee D18 on Soil and Rockand is the direct responsibility of Subcommittee D18.21 on Ground Water andVadose Zone Investigations.Current edition approved Jan. 1, 2005. Published February 2005. Originallyapproved in 1092. Last previous edition approved in 1999 as D 5299 99.1Copyright ASTM Internati
18、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.procedure. At this time, methods are not available to substan-tially determine the integrity of the decommissioning activity.1.6 The values stated in inch-pound units are to be regardedas the standard. The SI u
19、nits given in parentheses are forinformation only.1.7 This standard does not purport to address all of thesafety problems, 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 r
20、egulatory limitations prior to use.1.8 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
21、 this guide may 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
22、“ Standard” in the title of thisdocument means only that the document has been approvedthrough the ASTM consensus process.NOTE 5If state and local regulations are in effect where the decom-missioning is to occur, the regulations take precedence over this guide.2. Referenced Documents2.1 ASTM Standar
23、ds:2C 150 Specification for Portland CementD 420 Guide to Site Characterization for Engineering, De-sign and Construction PurposesD 4380 Test Method for Density of Bentonitic SlurriesD 5088 Practice for Decontamination of Field EquipmentUsed at Nonradioactive Waste SitesD 5092 Practice for Design an
24、d Installation of GroundWater Monitoring Wells in Aquifers3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 abandonmentsee decommissioning.3.1.2 attapulgite claya chain-lattice clay mineral. Theterm also applies to a group of clay minerals that are light-weight, tough, matted, a
25、nd fibrous.3.1.3 borehole television loga borehole or well videorecord produced by lowering a television camera into theborehole or well. This record is useful in visually observingdownhole conditions such as collapsed casing or a blockedscreen.3.1.4 blowouta sudden or violent uncontrolled escape of
26、fluids or gas, or both, from a borehole.3.1.5 caliper loga geophysical borehole log that shows toscale the variations with depth in the mean diameter of a casedor uncased borehole.3.1.6 cement, API, Class Aa cement intended for use fromthe surface to a depth of 6000 ft (1828 m). This cement issimila
27、r to ASTM Type I cement.3.1.7 cement, API, Class Ba cement intended for use fromthe surface to a depth of 6000 ft (1828 m) when conditionsrequire moderate- to high-sulfate resistance. This cement issimilar to ASTM Type II cement.3.1.8 cement, API, Class Cthis cement is intended for usefrom the surfa
28、ce to a depth of 6000 ft (1828 m) whenconditions require high early strength. This cement is similar toASTM Type III cement. Also available as a high sulfateresistant type.3.1.9 cement, API, Class Gthis cement is intended for usefrom the surface to a depth of 8000 ft (2438 m). It can be usedwith acc
29、elerators or retarders to cover a wide range of welldepths and temperatures. No additions other than calciumsulfate or water, or both, can be interground or blended with theclinker during manufacture of the cement. Also available asseveral sulfate-resistant types.3.1.10 cement, API, Class Hthis ceme
30、nt is intended foruse from the surface to a depth of 8000 ft (2438 m). It can beused with accelerators or retarders to cover a wide range ofwell depths and temperatures. No additions other than calciumsulfate or water, or both, can be interground or blended with theclinker during manufacture of the
31、cement. Also available as asulfate-resistant type.3.1.11 cement, API, Class Jthis cement is intended for usefrom depths of 12 000 to 16 000 ft (3658 to 4877 m) underconditions of extremely high temperatures and pressures. It canbe used with accelerators and retarders to cover a range of welldepths a
32、nd temperatures. No additions of retarders other thancalcium sulfate, or water, or both, can be interground orblended with the clinker during manufacture of the cement.3.1.12 cement bond (sonic) loga borehole geophysical logthat can be used to determine the effectiveness of a cement sealof the annul
33、ar space of a well.3.1.13 channelingthe process of forming a vertical cavityresulting from a faulty cement job in the annular space.3.1.14 curing acceleratora material added to cement todecrease the time for curing. Examples are sodium chloride,calcium sulfate (gypsum), and aluminum powder.3.1.15 cu
34、ring retardera material added to cement toincrease the time for curing. Sodium chloride in high concen-trations is an example.3.1.16 decommissioning (closure)the engineered closureof a well, borehole, or other subsurface monitoring devicesealed with plugging materials. Decommissioning also in-cludes
35、 the planning and documenting of all associated activi-ties. A synonym is abandonment.3.1.17 decontaminationthe process of removing undesir-able physical or chemical constituents, or both, from equip-ment to reduce the potential for cross-contamination.3.1.18 fallbackshrinkage, settlement, or loss o
36、f pluggingmaterial placed in a borehole or well.3.1.19 fire claya silicious clay rich in hydrous aluminumsilicates.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 t
37、he standards Document Summary page onthe ASTM website.D 5299 99 (2005)23.1.20 flow loga borehole geophysical log used to recordvertical movement of ground water and movement of waterinto or out of a well or borehole and between formations withina well.3.1.21 geophysical borehole loga log obtained by
38、 lower-ing an instrument into a borehole and continuously recording aphysical property of native or backfill material and containedfluids. Examples include resistivity, induction, caliper, sonic,and natural gamma logs.3.1.22 groutmaterial consisting of bentonite, cement, or acement-bentonite mixture
39、.3.1.23 grout pipea pipe or tube that is used to transportcement, bentonite, or other plugging materials from the groundsurface to a specified depth in a well or borehole. The materialmay be allowed to flow freely or it may be injected underpressure. The term tremie pipe is frequently used interchan
40、ge-ably.3.1.24 hydraulic communicationthe migration of fluidsfrom one zone to another, with reference to this guide;especially along a casing, grout plug, or through backfillmaterials.3.1.25 multiple-screened wellstwo or more monitoringwells situated in the same borehole.These devices can be eitheri
41、ndividual casing strings and screen set at a specific depth, awell with screens in more than one zone, or can consist ofdevices with screens with tubing or other collecting devicesattached that can collect a discrete sample.3.1.26 native materialin place geologic (or soil) materialsencountered at a
42、site.3.1.27 overdrillingthe process of drilling out a well cas-ing and any material placed in the annular space.3.1.28 perforationa slot or hole made in well casing toallow for communication of fluids between the well and theannular space.3.1.29 permanent plugginga seal that has a hydraulicconductiv
43、ity that is equivalent or less than the hydraulicconductivity of the geologic formation. This term is often usedwith uncased boreholes.3.1.30 plow layerthe depth typically reached by a plow orother commonly used earth turning device used in agriculture.This depth is commonly one to two feet (.3 m to
44、 .61 m) belowland surface.3.1.31 plugging materiala material that has a hydraulicconductivity equal to or less than that of the geologic forma-tion(s) to be sealed. Typical materials include portland cementand bentonite.3.1.32 pre-conditioningan activity conducted prior toplacing plugging material i
45、nto a borehole in order to stabilizethe hole.3.1.33 temporary decommissioningthe engineered clo-sure of a well intended to be returned to service at some laterdate (generally no more than six months). Temporary pluggingshould not damage the structural integrity of the well. Pluggingmaterials consist
46、 of sand, bentonite, or other easily removedmaterials.4. Summary of Guide4.1 Information is provided on the significance of properlydecommissioning boreholes and wells at sites containing orformerly containing solid or hazardous waste or hazardousmaterials or their byproducts, or that may be affecte
47、d by solidor hazardous waste materials or their byproducts in the future.This guide may be used in situations where water quality in oneaquifer may be detrimental to another aquifer either above orbelow the aquifer. The primary purpose of decommissioningactivities is to permanently decommission the
48、borehole ormonitoring device so that the natural migration of ground wateror soil vapor is not significantly influenced. Decommissionedboreholes and wells should have no adverse influence on thelocal environment than the original geologic setting.4.2 It is important to have a good understanding of t
49、hegeology, hydrogeology, well construction, historic and futureland use, chemicals encountered, and the regulatory environ-ment for successful decommissioning to occur.4.3 Various materials suitable for decommissioning bore-holes and wells are discussed, including their positive andnegative attributes for decommissioning. A generalized proce-dure is provided that discusses the process from planningthrough implementation and documentation. Examples of typi-cal practices are provided in the appendix.5. Significance and Use5.1 Decommissioning of bo
