1.1 本指南涵盖了适用于环境活动的以下永久退役（关闭）程序。它适用于发现固体或危险材料或废物的地方，或需要退役的情况下。本指南考虑了以下设备: 1.1.1 用于地质环境目的的钻孔（参见 注1 ), 1.1.2 监测井， 1.1.3 观察井， 1.1.4 注入井（见 注释2 ), 1.1.5 测压计， 1.1.6 用于提取受污染地下水、去除除水以外的漂浮或浸没物质（如汽油或四氯乙烯）的井，或用于提取土壤气体的其他装置， 1.1.7 用于建造监测井的钻孔，以及 1.1.8 装有渗流区监测装置的任何其他井或钻孔。 1.2 本指南不包括上述设备的临时退役。 注1: 本指南可用于现场未观察到污染的钻孔退役（见实践 D420 详细信息）；然而，本指南的主要用途是在已确定固体或危险废物的钻孔和油井退役。本指南中确定的方法也可用于其他情况，如供水井和钻孔的退役，其中存在受非有害污染物（如硝酸盐或硫酸盐）污染的水。 如果常规岩土工程研究表明现场存在污染，应参考本指南。咨询并遵守国家、州或地方法规，因为它们可能控制所需的退役程序。 注2: 本指南中使用术语“井”表示监测井、测压计或以类似井的方式建造的其他装置。所列的一些设备（如注入井和抽油井）可以使用本指南进行退役，以获取信息，但本文没有具体介绍。 注3: 由于建造这些类型的井所使用的方法很多，以及商业上可获得的多种类型，本指南中未提供多个屏蔽井退役的详细信息- 屏蔽井系统。然而，在某些情况下，可以使用本指南中介绍的方法，只需稍作修改。如何使用本指南的一个示例是通过过度钻井完全移除多个屏蔽井。 1.3 大多数监测井和测压管主要用于水质采样、水位观察或土壤气体采样或其组合，以确定质量。许多井的直径相对较小，通常为2.5至20厘米[1至8英寸]，用于监测地下水中的危险化学品。监测井的退役是必要的，以: 1.3.1 消除油井用于非预期用途的可能性， 1.3.2 防止污染物迁移到含水层或含水层之间， 1.3.3 防止污染物在渗流区迁移， 1.3.4 降低井内或井附近流体垂直或水平运移的可能性，以及 1.3.5 当油井不再能够修复或结构失效时，将其从有效使用中移除；不再需要监测；不再能够提供代表性样品或提供不可靠的样品；需要退役；或满足监管要求。 注4: 本指南中未定义井是否提供代表性水质样本的确定。 可能无法收集代表性水质样本的例子包括滤井网的生物或化学堵塞、水位降至滤井网底部以下或滤井网完全淤积。这些情况可能表明油井工作不正常。 1.4 本指南旨在提供有效永久关闭油井的信息，以使油井的物理结构不会提供含水层之间的水力通信方式，也不会与地表发生化学反应，从而对环境造成不利影响。 1.5 本指南的目的是提供程序，当遵循这些程序时，会对退役活动的完整性产生合理的置信度。 然而，验证退役程序的完整性可能不切实际。目前，还没有基本确定退役活动完整性的方法。 1.6 本指南也可用于其他系统的关闭或退役，这些系统可能允许污染物垂直或水平迁移或含水层的其他交叉污染，如挖井、地热回路，或在监管机构命令时。 1.7 单位- 以国际单位制或英寸-磅单位（括号中给出）表示的值应单独视为标准值。每个系统中规定的值可能不是精确的等效值； 因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 1.8 所有观察值和计算值应符合实践中确定的有效数字和舍入准则 D6026 ，除非被本标准取代。 1.9 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.10 本指南提供了有组织的信息收集或一系列选项，并不推荐具体的行动方案。本文件不能取代教育或经验，应与专业判断一起使用。并非本指南的所有方面都适用于所有情况。本ASTM标准不代表或取代必须根据其判断给定专业服务的充分性的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本文件。本文件标题中的“标准”一词仅表示该文件已通过ASTM共识程序获得批准。 注5: 如果要进行退役的地方的州和地方法规有效，则这些法规优先于本指南。 1.11 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 钻孔、监测井和其他设备的退役需要考虑每个现场的具体特征。 由于地质、生物和物理条件、施工实践以及周围土壤、岩石、废物和地下水的化学成分多种多样，因此无法使用单一的退役实践。本指南中讨论的程序旨在帮助地质学家或工程师选择计划、选择材料和执行有效永久退役操作所需的任务。应单独评估每种情况，并应用适当的技术以满足现场条件。本指南介绍了选择适当程序的注意事项，但也应考虑基于现场特定条件的其他注意事项。 注6: 理想情况下，退役应被视为监测井设计的一个组成部分。在此早期阶段进行规划可以使退役活动更容易完成。参见练习 D5092 有关监测油井施工的详细信息。 5.2 本指南旨在提供技术信息，并不取代当地管理机构的法规或条例。在退役过程中，适当监管机构的批准应该是一个重要的考虑因素。该实践通常符合其他国家和州油井退役指导文件（ANSI/NGWA- 01-14[1]1和加利福尼亚州环境保护局[2]。 注7: 本标准产生的结果的质量取决于执行该标准的人员的能力，以及所用设备和设施的适用性。符合标准的机构 D3740 通常认为能够胜任和客观的测试/采样/检查等。本标准的用户应注意遵守惯例 D3740 本身并不能保证可靠的结果。可靠的结果取决于许多因素，实践 D3740 提供了一种评估其中一些因素的方法。实践 D3740 是为从事土壤和岩石实验室测试和/或检查的机构开发的。 因此，它并不完全适用于执行这种做法的机构。然而，这种做法的用户应该认识到，实践框架 D3740 适用于评估执行此实践的机构的质量。目前，还没有已知的合格国家机构来检查执行这种做法的机构。 注8: 2001年至2009年，内布拉斯加州灌浆工作队对环形密封剂进行了广泛的研究 ( 2. ) . 这项研究包括水泥和膨润土灌浆以及颗粒和碎屑的使用。研究的总体发现表明，所有密封方法都会在非饱和带的油井部分出现收缩。 最好的灌浆是水泥砂、膨润土碎屑、纯水泥和固体含量超过20%的膨润土泥浆。尤其是在不饱和带使用低固体含量的膨润土泥浆，导致加利福尼亚州禁止使用这些泥浆 ( 3. ) . 区域或地方法规可能规定了不同于本标准密封指南的不同密封方法和混合物。 注9: 与开口、裂缝层或其他大开口（如洞穴）相交的油井退役可能会使密封和退役工作变得困难。在已知存在这些条件的地区，油井的退役应涉及在这些地区退役经验丰富的专业人员。

1.1 This guide covers procedures that are specifically related to permanent decommissioning (closure) of the following as applied to environmental activities. It is intended for use where solid or hazardous materials or wastes are found, or where conditions occur requiring the need for decommissioning. The following devices are considered in this guide: 1.1.1 A borehole used for geoenvironmental purposes (see Note 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 other than water such as gasoline or tetrachloroethylene, or other devices used for the extraction of soil gas, 1.1.7 A borehole used to construct a monitoring well, and 1.1.8 Any other well or boring that houses a vadose zone monitoring device. 1.2 Temporary decommissioning of the above is not covered in this guide. Note 1: This guide may be used to decommission boreholes where no contamination is observed at a site (see Practice D420 for details); however, the primary use of the guide is to decommission boreholes and wells where solid or hazardous waste have been identified. Methods identified in this guide can also be used in other situations such as the decommissioning of water supply wells and boreholes where water contaminated with nonhazardous pollutants (such as nitrates or sulfates) are present. This guide should be consulted in the event that routine geotechnical studies indicate the presence of contamination at a site. Consult and follow national, state, or local regulations as they may control required decommissioning procedures. Note 2: The term “well” is used in this guide to denote monitoring wells, piezometers, or other devices constructed in a manner similar to a well. Some of the devices listed such as injection and extraction wells can be decommissioned using this guide for information but are not specifically covered in detail in the text. Note 3: Details on the decommissioning of multiple-screened wells are not provided in this guide due to the many methods used to construct these types of wells and the numerous types of commercially available multiple-screened well systems. However, in some instances, the methods presented in this guide may be used with few changes. An example of how this guide may be used is the complete removal of the multiple-screened wells by overdrilling. 1.3 Most monitoring wells and piezometers are intended primarily for water quality sampling, water level observation, or soil gas sampling, or combination thereof, to determine quality. Many wells are relatively small in diameter typically 2.5 to 20 cm [1 to 8 inches] and are used to monitor for hazardous chemicals in groundwater. Decommissioning of monitoring wells is necessary to: 1.3.1 Eliminate the possibility that the well is used for purposes other than intended, 1.3.2 Prevent migration of contaminants into an aquifer or between aquifers, 1.3.3 Prevent migration of contaminants in the vadose zone, 1.3.4 Reduce the potential for vertical or horizontal migration of fluids in the well or adjacent to the well, and 1.3.5 Remove the well from active use when the well is no longer capable of rehabilitation or has failed structurally; is no longer needed for monitoring; is no longer capable of providing representative samples or is providing unreliable samples; is required to be decommissioned; or to meet regulatory requirements. Note 4: The determination of whether a well is providing a representative water quality sample is not defined in this guide. Examples of when a representative water quality sample may not be collected include the biological or chemical clogging of well screens, a drop in the water level to below the base of the well screen, or complete silting of the screen. These conditions may indicate that a well is not functioning correctly. 1.4 This guide is intended to provide information for effective permanent closure of wells so that the physical structure of the well does not provide a means of hydraulic communication between aquifers, with above surfaces or react chemically in a detrimental way with the environment. 1.5 The intent of this guide is to provide procedures that when followed result in a reasonable level of confidence in the integrity of the decommissioning activity. However, it may not be practical to verify the integrity of the decommissioning procedure. Currently, methods are not available to substantially determine the integrity of the decommissioning activity. 1.6 This guide may also be used for closure or decommissioning of other systems that could allow vertical or horizontal migration of contaminants or other cross-contamination of aquifers, such as dug wells, geothermal loops, or when ordered by regulatory agencies. 1.7 Units— The values stated in either SI units or inch-pound units (given in brackets) are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.8 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 , unless superseded by this standard. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.10 This guide offers an organized collection of information or a series of options and does not recommend a specific course of 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 replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word“ Standard” in the title of this document means only that the document has been approved through the ASTM consensus process. Note 5: If state and local regulations are in effect where the decommissioning is to occur, the regulations take precedence over this guide. 1.11 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Decommissioning of boreholes and monitoring wells, and other devices requires that the specific characteristics of each site be considered. The wide variety of geological, biological, and physical conditions, construction practices, and chemical composition of the surrounding soil, rock, waste, and groundwater precludes the use of a single decommissioning practice. The procedures discussed in this guide are intended to aid the geologist or engineer in selecting the tasks needed to plan, choose materials for, and carry out an effective permanent decommissioning operation. Each individual situation should be evaluated separately and the appropriate technology applied to meet site conditions. Considerations for selection of appropriate procedures are presented in this guide, but other considerations based on site specific conditions should also be considered. Note 6: Ideally, decommissioning should be considered as an integral part of the design of the monitoring well. Planning at this early stage can make the decommissioning activity easier to accomplish. See Practice D5092 for details on monitoring well construction. 5.2 This guide is intended to provide technical information and is not intended to supplant statutes or regulations of local governing bodies. Approval of the appropriate regulatory authorities should be an important consideration during the decommissioning process. This practice is in general accordance with other national and state guidance documents on well decommissioning (ANSI/NGWA-01-14 [1]1 and California EPA [2]. Note 7: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors, Practice D3740 provides a means of evaluating some of those factors. Practice D3740 was developed for agencies engaged in laboratory testing and/or inspection of soils and rock. As such, it is not totally applicable to agencies performing this practice. However, users of this practice should recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this practice. Currently, there is no known qualifying national authority that inspects agencies that perform this practice. Note 8: An extensive research program on annular sealants was conducted from 2001 through 2009 and in subsequent years by the Nebraska Grout Task Force ( 2 ) . This research included cement and bentonite grouts and the use of pellets and chips. The general finding of the study indicates all sealing methods suffer from some shrinkage in the portion of the well in the unsaturated zone. The best grouts were cement-sand, bentonite chips, neat cements and bentonite slurries with more than 20 percent solids. Especially problematic is the use of low solids content bentonite slurries in the unsaturated zone leading to a prohibition on their use in California ( 3 ) . Regional or local regulations may specify different sealing methods and mixtures that differ from seal guideline in this standard. Note 9: The decommissioning of wells that intersect openings, fractured layers or other large openings, such as caves, can make sealing and decommissioning efforts difficult. The decommissioning of wells in areas known to have these conditions should involve professionals experienced in decommissioning in these areas.