1、Designation: D5787 95 (Reapproved 2009)D5787 14Standard Practice forMonitoring Well Protection1This standard is issued under the fixed designation D5787; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis practice for monitoring well protection is provided to promote durable and reliable protectionof installed monitoring wells agains
3、t natural and man caused damage.The practices contained promotethe development and planning of monitoring well protection during the design and installation stage.1. Scope Scope*1.1 This practice identifies design and construction considerations to be applied to monitoring wells for protection from
4、naturaland man caused damage ordamage and/or impacts.1.2 The installation and development of a well is a costly and detailed activity with the goal of providing representative samplesand data throughout the design life of the well. Damages to the well at the surface frequently result in loss of the
5、well or changesin the data. This standard provides for access control so that tampering with the installation should be evident. The design andinstallation of appropriate surface protection will mitigate the likelihood of damage or loss.1.3 This practice may be applied to other surface or subsurface
6、 monitoring device locations, such as piezometers, permeameters,temperature or moisture monitors, or seismic devices to provide protection.1.4 UnitsThe values stated in inch-pound SI (inch-pound) units are to be regarded as standard. No other units of measurementare included in this standard.1.5 Thi
7、s practice offers a set of instructions for performing one or more specific operations. This document cannot replaceeducation or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may beapplicable in all circumstances. This ASTM standard is not
8、intended to represent or replace the standard of care by which theadequacy of a given professional service must be judged, nor should this document be applied without consideration of a projectsmany unique aspects. The word “Standard” in the title of this document means only that the document has be
9、en approved throughthe ASTM consensus process.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regula
10、torylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C150D653 Specification for Portland CementTerminology Relating to Soil, Rock, and Contained FluidsC294 Descriptive Nomenclature for Constituents of Concrete AggregatesD5092D5918 Practice for Design and Installation of Groundwate
11、r Monitoring WellsTest Methods for Frost Heave and ThawWeakening Susceptibility of Soils3. Terminology3.1 Definitions:3.1.1 For definitions of common technical terms in this standard, refer to Terminology D653.1 This practice is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is th
12、e direct responsibility of Subcommittee D18.21 on Groundwater and VadoseZone Investigations.Current edition approved April 1, 2009Oct. 1, 2014. Published April 2009October 2014. Originally approved in 1995. Last previous edition approved in 2000 asD5787 95 (2009). (2000). DOI: 10.1520/D5787-95R09.10
13、.1520/D5787-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is i
14、ntended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the cu
15、rrent versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 Definitions:Definitions o
16、f Terms Specific to This Standard:3.2.1 barrierbarrier, nany device that physically prevents access or damage to an area.3.2.2 barrier markersmarkers, nplastic, or metal posts, often in bright colors, placed around a monitoring well to aid inidentifying or locating the well.3.2.3 barrierbollards, po
17、stsnsteel pipe, typically from 4 to 12 inches10 to 30 cm (4 to 12 in.) in diameter and normally filledwith concrete or grout that are placed around a well location to protect the well from physical damage, such as from vehicles.3.1.4 boreholea circular open or uncased subsurface hole created by dril
18、ling.3.1.5 casingpipe, finished in sections with either threaded connections or bevelled edges to be field welded, which is installedtemporarily or permanently to counteract caving, to advance the borehole, or to isolate the zone being monitored, or a combinationthereof.3.1.6 casing, protectivea sec
19、tion of larger diameter pipe that is emplaced over the upper end of a smaller diameter monitoringwell riser or casing to provide structural protection to the well and restrict unauthorized access into the well.3.1.7 riserthe pipe extending from the well screen to or above the ground surface.3.2.4 se
20、aled capcap, na sealable riser PVC, steel, or alloy pipe end cap, normally gasketed or sealed, that is designed toprevent water or other substances from entering into, or out of the well riser.3.1.9 vented capa cap with a small hole that is installed on top of the riser.4. Significance and Use4.1 An
21、 adequately designed and installed surface protection system will mitigate the consequences of naturally natural damage(that is, freeze/thaw damage) in susceptible areas, or man caused damages (that is, from vehicles), which could otherwise occurand result in either changes to the data, or complete
22、loss of the monitoring well.4.2 The extent of application of this practice may depend upon the importance of the monitoring data, cost of monitoring wellreplacement, expected or design life of the monitoring well, the presence or absence of potential risks, and setting or location ofthe well.4.3 Mon
23、itoring well surface protection should be a part of the well design process, and installation of the protective systemshould be completed at the time of monitoring well installation and development.4.4 Information determined at the time of installation of the protective system will form a baseline f
24、or future monitoring wellinspection and maintenance. Additionally, elements of the protection system will satisfy some regulatory requirements such as forprotection of near surface groundwater and well identification.5. Design Considerations5.1 The design of a monitoring well protective system is li
25、ke other design processes, where the input considerations aredetermined and the design output seeks to remedy or mitigate the negative possibilities, while taking advantage of the sitecharacteristics.5.2 The factors identified in this practice should be considered during the design of the monitoring
26、 well protective system. Thefinal design should be included in the monitoring well design and installation documentation and be completed and verified duringthe final completion and development of the well.5.3 In determining the level or degree of protection required, the costs and consequences, suc
27、h as loss of data or replacementof the well, must be weighed against the probability of occurrence and the desired life of the well. For monitoring wells whichwill be used to obtain data over a short time period, the protection system may be minimal. For wells which are expected to beused for an ind
28、efinite period, are in a vulnerable location, and for which the costs of lost data could be high, the protective systemshould be extensive. Factors to consider and methods of mitigating them are presented in the following sections.5.3.1 Impact DamagesPhysical damages resulting from construction equi
29、pment, livestock, or vehicles striking the monitoringwell casing frequently occur. Protective devices and approaches include:5.3.1.1 Extra heavy protective casings with a reinforced concrete apron extending several feet 1 m or more (3 ft or more) aroundthe casing may be an acceptable design in those
30、 areas where frost heave is not a problem. The principle behind this is to designthe protective casing so that it will be able to withstand the impact of vehicles without damage to the riser within.5.3.1.2 Barrier Posts Bollards placed in an array such that any anticipated vehicle can not pass betwe
31、en them to strike theprotective casing. Barrier posts Bollards are typically filled with concrete and set in post holes several feet deep 1 m and greater(3 ft and greater) in depth, which are backfilled with concrete. Barrier posts Bollards typically extend from 3 to 5 feet1 to 1.5 m(3 to 5 ft) abov
32、e the ground surface. Barrier posts Bollards are frequently used in and around industrial or high vehicle traffic areas.Costs for installation can be substantial however they provide a high degree of protection for exposed wells. Cost of removal atdecommissioning can also be substantial.NOTE 1Cattle
33、 frequently rub against above ground completions leading to damage of unprotected casings. Concrete filled posts or driven T-posts,wrapped with barbed wire, are frequently used.D5787 1425.3.1.3 Barrier Markersmarkers are relatively lightweight metal or often plastic posts which provide minimal impac
34、t resistancebut which by their color, location, and height, warn individuals of the well presence. The use of barrier markers is effective in areasthat are well protected from impact type damage by other features, such as surrounding structures or fences. They are relativelyinexpensive to install.5.
35、3.1.4 SignsAn inexpensive means of identifying the presence of a monitoring well. Signs provide protection only bywarning of the well presence. Signs may be required in some circumstances and appropriate in others. Wells known to containhazardous, radioactive, or explosive compounds should be marked
36、 to warn sampling personnel of potential dangers. When apotential exists for water usage, signage indicating that the water is non-potable and is utilized strictly as a monitoring well, andnot for any other purpose, may be appropriate. Disadvantages of signs are that they may be ignored, are often d
37、ifficult to maintain,and may invite vandalism to the well.5.3.1.4 Recessed or Subsurface casings may be used to mitigate impact damage by allowing the vehicles to pass over.Frequently used techniques include recessing the casing below ground level, using commercially available covers. These may take
38、the form of valve pits or manholes, as examples. Advantages include both protecting the well while minimizing the interferenceto surface traffic, such as in parking lots or urban areas and screening the well from view. Using this technique, wells may belocated in the most desired locations from a gr
39、oundwater monitoring perspective. Disadvantages include the need to assureensuresurface drainage does not enter the well riser, either by maintaining positive drainage or by using a sealed riser cap (or both). Whenthe risk is from the influx of surface water, drains below the level of the riser shou
40、ld be installed. In extreme cases, such as inlocation with high groundwater levels or potential drainage from surrounding areas, automatic sump pumps may be required.Consideration should be given to the sampling personnel who will require adequate space to perform sampling, particularly inmanhole si
41、tuations. Additionally, personnel protection requirements from working in a confined space should be considered.5.3.1.5 Fencing, such as commercial chainlink type fences may provide adequate protection in areas with light risk fromvehicles, but where people or animals may interfere or affect the wel
42、l. Advantages are relative minimal costs, ease of removal oropening. Disadvantages include maintenance, adequacy of protection from hard vehicle impacts, and visual and traffic interference.5.3.2 VandalismDamage from vandals can take two forms, those which seek to damage or destroy the well itself,
43、and thosewhich intend to damage the data that the well may provide. Theft of sampling pumps, loss of access to the riser, plugging of thewell with foreign debris, or injection of foreign materials or chemicals are potential results of vandalism.5.3.2.1 Physical damage to the well can be minimized wi
44、th many of the same techniques as used to protect the well from impactdamages. Generally two techniques can be used to protect a well from physical damage, one, by hiding or camouflaging the well,the other by constructing the surface protection of the well with multiple physical barriers. Hiding or
45、camouflaging the well utilizesthe philosophy that what cant be found cant be damaged. Camouflage techniques include enclosing the well in manholes orsumps, planting shrubs or vegetation to shield the well from view, enclosing the well in another structure, such as inside a raisedplanter or a small s
46、hed. Color characteristics of the above ground can be used to disguise the well or to assist in making it blendinto the surroundings. Costs for camouflage can vary widely, but are generally minimal when included with other protections.Disadvantages are that if found, the well is still susceptible to
47、 damage by vandals, that damage may be undetected, and thatsampling personnel not familiar with the well may have difficulty locating it.5.3.2.2 Protection from vandalism is generally achieved by constructing multiple physical barriers. The first barrier shouldalways include a rugged protective casi
48、ng with a locking cap or lid. The lock quality can vary from relatively inexpensive andeasily broken types to more costly high security type locks. Locks used on wells are subject to weather, dirt and deterioration.FIG. 1 Example of Protective DesignD5787 143Frequently locks must be cut if not regul
49、arly maintained and the design and selection of the cap and lock should include thisconsideration. Construction of the hasps, locking lugs, or other mechanisms should be rugged, made of metal and welded toprevent access to the casing by prying, hammering or other typical vandalism. The casing should be heavy enough to resistpenetration by bullets in areas where shooting may occur. A concrete apron or grout collar around the casing will provide massto defeat attempts to pull the casing upwards, or sideways. Additional physical barriers should be added in cons
