1、Designation: D5978 96 (Reapproved 2011)1D5978/D5978M 16Standard Guide forMaintenance and Rehabilitation of Groundwater MonitoringWells1This standard is issued under the fixed designation D5978;D5978/D5978M; the number immediately following the designation indicatesthe year of original adoption or, i
2、n 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.1 NOTEEditorial changes were made throughout in December 2011.INTRODUCTIONThis guide for maint
3、enance and rehabilitation promotes procedures appropriate to groundwatermonitoring wells installed to evaluate the extent and nature of contamination, progress of remediation,and for long-term monitoring of either water quality or water level.1. Scope Scope*1.1 This guide covers an approach to selec
4、ting and implementing a well maintenance and rehabilitation program forgroundwater monitoring wells. It provides information on symptoms of problems or deficiencies that indicate the need formaintenance and rehabilitation. It is limited to monitoring wells, that are designed and operated to provide
5、access to, representativewater samples from, and information about the hydraulic properties of the saturated subsurface while minimizing impact on themonitored zone. Some methods described herein may apply to other types of wells although the range of maintenance andrehabilitation treatment methods
6、suitable for monitoring wells is more restricted than for other types of wells. Monitoring wellsinclude their associated pumps and surface equipment.1.2 This guide is affected by governmental regulations and by site specific geological, hydrogeological, geochemical,climatological, and biological con
7、ditions.1.3 UnitsThe values stated in either inch-pound units or SI units presented in brackets are to be regarded separately asstandard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently ofthe other. Combining values from the two syste
8、ms may result in non-conformance with the standard.1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in PracticeD 6026, unless superseded by this standard.1.5 This standard does not purport to address all of the safety concerns, if
9、 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 regulatorylimitations prior to use.1.6 This guide offers an organized collection of information or a series of options and does
10、not recommend a specific courseof action. This document cannot replace education or experience and should be used in conjunction with professional judgment.Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replacethe standard of
11、care by which the adequacy of a given professional service must be judged, nor should this document be appliedwithout consideration of a projects many unique aspects. The word “Standard” in the title of this document means only that thedocument has been approved through the ASTM consensus process.1
12、This guide is under the jurisdiction of ASTM Committee D18 on Soil and Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and VadoseZone Investigations.Current edition approved Dec. 1, 2011July 1, 2016. Published December 2012July 2016. Originally approved in 1996. Last prev
13、ious edition approved in 20052011 asD5978 96 (2005).(2011)1. DOI: 10.1520/D5978-96R11E01.10.1520/D5978_D5978M-16.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not
14、be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end
15、of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12. Referenced Documents2.1 ASTM Standards:2D652 Method of Test for Measuring Mica Stampings Used in Electronic Devices and Incandescent Lamps (Withdrawn 1956)3D653 Termin
16、ology Relating to Soil, Rock, and Contained FluidsD1889D3740 Test Method for Turbidity of WaterPractice for Minimum Requirements for Agencies Engaged in Testing and/orInspection of Soil and Rock as Used in Engineering Design and Construction (Withdrawn 2007)D4044 Test Method for (Field Procedure) fo
17、r Instantaneous Change in Head (Slug) Tests for Determining Hydraulic Propertiesof AquifersD4412 Test Methods for Sulfate-Reducing Bacteria in Water and Water-Formed DepositsD4448 Guide for Sampling Ground-Water Monitoring WellsD4750 Test Method for Determining Subsurface Liquid Levels in a Borehole
18、 or Monitoring Well (Observation Well)(Withdrawn 2010)3D5088 Practice for Decontamination of Field Equipment Used at Waste SitesD5092 Practice for Design and Installation of Groundwater Monitoring WellsD5254 Practice for Minimum Set of Data Elements to Identify a Ground-Water SiteD5299 Guide for Dec
19、ommissioning of Groundwater Wells, Vadose Zone Monitoring Devices, Boreholes, and Other Devices forEnvironmental ActivitiesD5408 Guide for Set of Data Elements to Describe a Groundwater Site; Part OneAdditional Identification DescriptorsD5409 Guide for Set of Data Elements to Describe a Ground-Water
20、 Site; Part TwoPhysical DescriptorsD5410 Guide for Set of Data Elements to Describe a Groundwater Site;Part ThreeUsage Descriptors (Withdrawn 2016)3D5472 Test Method for Determining Specific Capacity and Estimating Transmissivity at the Control WellD5474 Guide for Selection of Data Elements for Grou
21、ndwater InvestigationsD5521 Guide for Development of Groundwater Monitoring Wells in Granular AquifersD5753 Guide for Planning and Conducting Borehole Geophysical Logging2.1.1 In addition, ASTM Volume 11.01 on Water (I) and Volume 11.02 on Water (II) contain numerous test methods andstandards that m
22、ay be of value to the user of this guide.2.1.1D7726 In addition, ASTM Volume 11.01 on Water (I) and Volume 11.02 on Water (II) contain numerous test methods andstandards that may be of value to the user of this guide.Guide for The Use of Various Turbidimeter Technologies forMeasurement of Turbidity
23、in Water3. Terminology3.1 Definitions:3.1.1 For definitions of common technical terms in this standard, refer to Terminology D652D653 and Guide D5521.3.2 Definitions of Terms Specific to This Standard:3.2.1 well developmentdevelopment, nactions taken during the installation and start-up of a well fo
24、r the purpose ofmitigating or correcting damage done to the adjacent geologic formations and filter materials that might affect the wells abilityto produce representative samples.3.2.2 well maintenancemaintenance, nany action that is taken for the purpose of maintaining well performance (seeDiscussi
25、on) and extending the life of the well to provide samples that are representative of the groundwater surrounding it.Maintenance includes both physical actions taken at the well and the documentation of those actions and all operating data in orderto provide benchmarks for comparisons at later times.
26、3.2.2.1 DiscussionMaintenance includes both physical actions taken at the well and the documentation of those actions and all operating data in orderto provide benchmarks for comparisons at later times. Desired level of well performance can vary depending on the designobjectives.3.2.3 well preventiv
27、e maintenancemaintenance, nany well maintenance action that is initiated for the purpose of meetingsome preestablished rule or schedule that applies while well performance is still within preestablished ranges.3.2.4 well reconstructive maintenancemaintenance, nany preventive or rehabilitative well m
28、aintenance action involving thereplacement of a major component (for example, pump, surface protection).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
29、 Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.D5978/D5978M 1623.2.5 well redevelopmentredevelopment, nany preventive or rehabilitative well maintenance action, taken after start-up, forthe purpose of mitigating or cor
30、recting deterioration of the filter pack or adjacent geologic formations, or both, due to the wellspresence and operation over time, usually involving physical development procedures, applied in reaction to deterioration.3.2.6 well rehabilitationrehabilitation, nfor the purposes of this guide, synon
31、ymous with well rehabilitative or restorativemaintenance.3.2.7 well rehabilitative or restorative maintenancemaintenance, nany well maintenance action that is initiated for thepurpose of correcting well performance that has moved outside of preestablishedpre-established ranges.4. Significance and Us
32、e4.1 The process of operating any engineered system, such as monitoring wells, includes active maintenance to prevent, mitigate,or reverse deterioration. Lack of or improper maintenance can lead to well performance deficiencies (physical problems) or samplequality degradation (chemical problems). Th
33、ese problems are intrinsic to monitoring wells, which are often left idle for longperiods of time (as long as a year), installed in non-aquifer materials, and installed to evaluate contamination that can cause locallyanomalous hydrogeochemical conditions. The typical solutions for these physical and
34、 chemical problems that would be appliedby owners and operators of water supply, dewatering, recharge, and other wells may not be appropriate for monitoring wellsbecause of the need to minimize their impact on the conditions that monitoring wells were installed to evaluate.4.2 This guide covers acti
35、ons and procedures, but is not an encyclopedic guide to well maintenance. Well maintenance planningand execution is highly site and well specific.4.3 The design of maintenance and rehabilitation programs and the identification of the need for rehabilitation should be basedon objective observation an
36、d testing, and by individuals knowledgeable and experienced in well maintenance and rehabilitation.Users of this guide are encouraged to consult the references provided.4.4 For additional information see Test Methods D1889, D4412, D5472, D7726 and Guides D4448, D5254, D5521, D5409,D5410 and D5474.NO
37、TE 1The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of theequipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objectivetesting/samplin
38、g/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliableresults depend on many factors; Practice D3740 provides a means of evaluating some of those factors.Practice D3740 was developed for agencies engaged in the
39、testing and/or inspection of soils and rock. As such, it is not totally applicable to agenciesperforming this practice. However, user of this practice should recognize that the framework of Practice D3740 is appropriate for evaluating the qualityof an agency performing this practice. Currently there
40、 is no known qualifying national authority that inspects agencies that perform this practice.5. Well Performance Deficiencies5.1 Proper well design, installation, and development can minimize well performance deficiencies that result in the need formaintenance and rehabilitation. Practice D5092 and
41、Guide D5521 should be consulted. Performance deficiencies include: sand,silt, and clay infiltration; low yield; slow responses to changes in groundwater elevations; and loss of production.5.2 Preventable Causes of Poor Well Performance:5.2.1 Inappropriate well location or screened interval. These ma
42、y be unavoidable if a requirement for site characterization ormonitoring exists,exists;5.2.2 Inappropriate drilling technique or methodology for materials screened,screened;5.2.3 Inadequate intake structure design (screen, filter material, and so forth),forth);5.2.4 Inappropriate well construction m
43、aterials. This may lead to corrosion or collapse,collapse;5.2.5 Improper construction, operation, or maintenance, or combination thereof, of borehole or well, wellhead protection, wellcap, andand/or locking device,device;5.2.6 Ineffective development,development;5.2.7 Inappropriate pump selection,se
44、lection; and5.2.8 Introduction of foreign substances.5.3 Physical Indicators of Well Performance Deficiencies Include:5.3.1 Sand, Silt, and Clay InfiltrationCauses include inappropriate and inadequate well drilling (for example, auger flightsmearing), improper screen and filter pack, improper casing
45、 design or installation, incomplete development, screen corrosion, orcollapse of filterpack. filter pack. In rock wells, causes include the presence of fine material in fractures. The presence of sand, silt,or clay can result in pump and equipment wear and plugging, turbid samples, filterpack filter
46、 pack plugging, or combinationthereof.5.3.2 Low YieldCauses include dewatering, collapse or consolidation of fracture or water-bearing zone, pump malfunction orplugging, screen encrustation or plugging, and pump tubing corrosion or perforation.perforation or clogging.5.3.3 Water Level DeclineCauses
47、include area or regional water level decline, well interference, and chemical or microbialplugging or encrustation of the borehole, screen, or filterpack.filter pack.5.3.4 Loss of ProductionUsually caused by pump failure, but can also be caused by dewatering, plugging, or well collapse.D5978/D5978M
48、1635.3.4.1 Well CollapseCan be caused by tectonism, ground subsidence, failure of unsupported casing (that is, in caves orbecause of faulty grout), corrosion and subsequent failure of screen and casing, improper casing design, local site operations,freeze-thaw, or improper chemical or mechanical reh
49、abilitation.5.3.5 Observation of physical damage or other indicator.6. Sample Quality Degradation6.1 All of the preceding physical well performance deficiencies can result in sample quality degradation by dilution,cross-contamination, or entrainment of solid material in water samples. In addition, chemical and biological activity can bothdegrade well performance and sample quality. Any change in well or aquifer chemistry that results from the presence of the wellcan interfere with accurate characterization of a site.6.2 Physical IndicatorsChemica
