1.1 本指南侧重于从水生环境中选择沉积物背景参考区，以确定沉积物地点沉积物的代表性背景浓度。这些浓度通常用于根据各种监管计划（包括《综合环境反应、赔偿和责任法案》（CERCLA））采取的污染沉积物纠正措施。尽管本指南中引用的许多参考文献都是《综合环境反应、赔偿和责任法案》- 该指南面向，适用于在地方、州、部落、联邦和国际清理计划下采取的补救措施。然而，本指南没有详细说明每个司法管辖区的现有背景要求或指导。应审查执行纠正措施的监管实体的要求，以确认合规性。 1.1.1 使用本指南选择的沉积物背景参考区域需要得到具有管辖权的监管机构的批准（或者他们不应该对所选区域有任何例外），特别是如果所开发的沉积物的代表性背景浓度可能被用来制定沉积物补救标准。 1.2 本指南提供了一个框架，用于选择适当的沉积物背景参考区域，以收集沉积物数据，从而为沉积物地点的沉积物制定具有代表性的背景浓度。它旨在告知、补充和支持（但不取代）地方、州、部落、联邦或国际机构制定的要求或指导方针。 1.2.1 本指南旨在适用于已收集沉积物数据且随时可用的污染沉积物现场。 此外，它假设已经进行了风险评估，从而确定了超过基于风险的沉积物阈值的潜在关注污染物（PCOC）。本指南可应用于项目生命周期内的多个点（如现场评估和补救设计）。 1.2.2 此外，本指南假定，已确定的基于风险的沉积物阈值足够低，足以对纠正措施的实施构成挑战，或者沉积物场地受到不受控制的持续人为或自然来源（或两者兼而有之）的再次污染。 在任何一种情况下，沉积物的代表性背景浓度都有助于确定纠正补救措施的程度（当用作补救目标时），评估这些代表性本底浓度带来的风险，并制定适当的补救后监测计划。 1.2.3 本文介绍了一个使用分层决策分析方法选择背景参考区域的案例研究 附录X1 它将与前高地制造天然气厂（MGP）设施相关的假设沉积物场地的各种特征与三个候选背景参考区域进行了比较，并确定了在选择单个背景参考区域时最能满足决策分析目标的背景参考区域。 1.3 相关ASTM标准-- 本指南与其他几本指南相关。指南 E3382 为污染沉积物场地沉积物代表性背景浓度的发展提供了总体框架，包括概念性场地模型（CSM）考虑因素。指南 E3242 描述了如何评估候选背景数据集（包括使用统计、地球化学和化学法医方法）以获得代表性背景数据集，然后如何使用这些数据集来确定沉积物的代表性背景浓度。 指南 E3164 涵盖了现场用于获取沉积物样本的采样方法（无论是从沉积物现场还是背景参考区），以及指南 E3163 讨论了用于沉积物样本中PCOC化学分析的适当实验室方法。指南 D4823 与沉积物岩心取样有关的，也与本指南有关。 1.3.1 具体而言，本指南旨在在《指南》的总体框架下使用 E3382 ，结合《指南》中概述的评估数据和制定具有代表性的沉积物背景浓度的详细框架 E3242 ，以帮助确保在代表性背景浓度开发中选择适当的背景参考区域。 1.4 单位-- 以国际单位制表示的值应被视为标准。本指南中不包括其他计量单位。 1.5 本标准并不旨在解决与其使用相关的所有安全问题（如果有的话）。本标准的使用者有责任在使用前建立适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 =====意义和用途====== 4.1 预期用途: 4.1.1 本指南可供参与沉积物纠正措施计划的各方使用，包括监管机构、项目赞助商、环境顾问、毒理学家、风险评估员、现场修复专业人员、环境承包商和其他利益相关者。 4.2 CSM的重要性: 4.2.1 CSM应根据需要进行更新和完善，以描述沉积物纠正措施项目的物理性质、化学成分和发生、生物特征和环境条件（指南 E1689 ). 4.3 参考材料: 4.3.1 本指南应与中列出的其他ASTM指南结合使用 2.1 （尤其是导游 E3242 和 E3382 ); 本指南还应与本指南末尾的参考文献中的材料结合使用（包括 1. ). 3. 使用这些参考材料将指导用户为沉积物现场的沉积物制定具有代表性的背景浓度。 4.4 灵活的现场具体实施: 4.4.1 本指南提供了一个系统但灵活的框架，以适应监管机构和用户根据项目目标、场地复杂性、独特场地特征、监管要求、新制定的指南、新发表的科学研究、监管标准的变化、科学知识和技术能力的进步以及不可预见的情况而采取的方法的变化。 4.5 监管框架: 4.5.1 本指南旨在适用于广泛的地方、州、部落、联邦（如《综合环境反应、赔偿和责任法案》）或国际司法管辖区，每个司法管辖区都有自己独特的监管框架。因此，本指南不详细讨论与这些监管框架相关的要求或指导，也不打算取代适用的法规和指导。本指南的用户需要了解工作所在司法管辖区的监管要求和指导。 4.5.2 根据管辖区的监管要求，选择背景参考区可能需要考虑关键栖息地和生态受体。 4.6 系统项目规划和范围界定过程: 4.6.1 在应用本指南时，用户应进行系统的项目规划和范围界定过程，以收集信息，协助为特定项目做出特定于现场的用户定义决策，包括组建一支经验丰富的项目专业团队。 这些从业者应具备适当的专业知识，以确定范围、计划和执行沉积物数据采集和分析程序。该团队可能包括但不限于项目赞助商、环境顾问、毒理学家、现场修复专业人员、分析化学家、地球化学家和统计学家。 4.7 其他注意事项: 4.7.1 本指南并不涵盖为沉积物制定代表性背景浓度的计划的所有组成部分。 它旨在与其他指南（如指南）结合使用 E3163 , E3164 , E3240 , E3242 ，以及 E3382 )这样做。 4.7.2 本指南不包括沉积物取样和实验室分析。指南 E3163 和 E3164 包含有关沉积物取样和实验室分析的广泛信息。 4.7.3 本指南未涵盖数据质量目标。数据质量目标在 ( 2. ) . 4.7.4 本指南未涵盖背景研究设计考虑因素，但在其他参考文献中进行了描述，包括指南 E3163 和 ( 3. ) . 4.7.5 本指南中没有详细介绍使用数据评估方法从候选背景数据集中获取代表性背景数据集，但在指南中进行了更深入的讨论 E3242 . 4.7.5.1 指南中详细讨论了从候选背景数据集中识别和删除高非检测值 E3242 . 4.7.5.2 在实践中详细讨论了从候选背景数据集中识别和删除异常值 E178 ，以及指南 E3242 . 4.7.5.3 指南中详细讨论了用于评估候选背景数据集以获得代表性背景数据集的地球化学和化学法医方法 E3242 ; 本指南讨论了它们在背景参考区域选择过程中的应用。 4.7.6 指南中详细讨论了使用统计方法从代表性背景数据集中开发BTV E3242 . 4.7.7 指南中详细讨论了使用统计方法将代表性背景数据集与沉积物现场数据集进行比较 E3242 . 4.7.8 本指南中没有深入讨论地理空间分析考虑因素，但与环境评估相关的讨论更为深入 ( 4. ) ，重点关注与地理空间分析相关的质量保证问题。 4.7.9 在本指南中，泥沙( 3.1.15 )被定义为在水体底部发现的物质。沉积成因的高地土壤在本指南中不作为沉积物考虑。 4.7.10 在本指南中，只有PCOC浓度被认为在范围内。 残余本底放射性超出范围。 4.8 本指南的结构和组成部分: 4.8.1 本指南的用户在继续使用之前应查看本指南的整体结构和组成部分，包括: 第节 1. 范围 第节 2. 参考文件 第节 3. 术语 第节 4. 意义和用途 第节 5. 沉积地点沉积物代表性背景浓度概述和发展框架 第节 6. 背景参考区域选择标准 第节 7. 关键词 附录X1 案例研究 工具书类

1.1 This guide focuses on the selection of sediment background reference areas from aquatic environments for the purpose of developing representative background concentrations for sediment at sediment sites. These concentrations are typically used in contaminated sediment corrective actions performed under various regulatory programs, including the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Although many of the references cited in this guide are CERCLA-oriented, the guide is applicable to remedial actions performed under local, state, tribal, federal, and international cleanup programs. However, this guide does not provide a detailed description of the existing background requirements or guidance for each jurisdiction. The requirements for the regulatory entity under which the corrective action is being performed should be reviewed to confirm compliance. 1.1.1 The sediment background reference areas chosen using this guide will need to be approved by the regulatory agency having jurisdiction (or they should take no exception to the areas chosen), especially if the representative background concentrations for sediment developed will potentially be used to set sediment remedial criteria. 1.2 This guide provides a framework to select appropriate sediment background reference areas for the collection of sediment data in the development of representative background concentrations for sediment at sediment sites. It is intended to inform, complement, and support (but not supersede) the requirements or guidelines established by local, state, tribal, federal, or international agencies. 1.2.1 This guide is designed to apply to contaminated sediment sites where sediment data have been collected and are readily available. Additionally, it assumes that risk assessments have been performed, so that the potential contaminants of concern (PCOCs) that exceed risk-based thresholds for sediment have been identified. This guide can be applied at multiple points within the project life cycle (such as site assessment and remedial design). 1.2.2 Furthermore, this guide presumes that the identified risk-based thresholds for sediment are low enough to pose corrective action implementation challenges or that the sediment site is subject to recontamination from ongoing anthropogenic or naturally occurring sources (or both) that are not controlled. In either case, representative background concentrations for sediment are useful for determining the extent of corrective remedial actions (when used as remedial goals), evaluating risks posed by these representative background concentrations, and establishing appropriate post-remedial monitoring plans. 1.2.3 A case study for selecting a background reference area using a tiered decision analysis approach is presented in Appendix X1 . It compares various characteristics of a hypothetical sediment site associated with a former upland manufactured gas plant (MGP) facility to three candidate background reference areas and identifies the background reference area that best satisfies the decision analysis objectives in the choice of a single background reference area. 1.3 Related ASTM Standards— This guide is related several other guides. Guide E3382 provides the overarching framework for the development of representative background concentrations for sediment at contaminated sediment sites, including Conceptual Site Model (CSM) considerations. Guide E3242 describes how to evaluate candidate background data sets (including the use of statistical, geochemical, and chemical forensic methodologies) to obtain representative background data sets and then how to use these data sets to develop representative background concentrations for sediment. Guide E3164 covers the sampling methodologies used in the field to obtain sediment samples (whether from the sediment site or background reference areas), and Guide E3163 discusses appropriate laboratory methodologies to use for the chemical analysis of PCOCs in sediment samples. Guide D4823 , which concerns sediment core sampling, is also related to this guide. 1.3.1 Specifically, this guide is intended to be used under the overarching framework of Guide E3382 , in conjunction with the detailed framework to evaluate data and develop representative background concentrations for sediment outlined in Guide E3242 , to help ensure appropriate background reference areas are chosen for use in representative background concentration development. 1.4 Units— The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this guide. 1.5 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. 1.6 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 ====== 4.1 Intended Use: 4.1.1 This guide may be used by various parties involved in sediment corrective action programs, including regulatory agencies, project sponsors, environmental consultants, toxicologists, risk assessors, site remediation professionals, environmental contractors, and other stakeholders. 4.2 Importance of the CSM: 4.2.1 The CSM should be updated as needed and refined to describe the physical properties, chemical composition and occurrence, biologic features, and environmental conditions of the sediment corrective action project (Guide E1689 ). 4.3 Reference Material: 4.3.1 This guide should be used in conjunction with other ASTM guides listed in 2.1 (especially Guides E3242 and E3382 ); this guide should also be used in conjunction with the material in the References at the end of this guide (including 1 ). 3 Using these reference materials will direct the user in developing representative background concentrations for sediment at a sediment site. 4.4 Flexible Site-Specific Implementation: 4.4.1 This guide provides a systematic but flexible framework to accommodate variations in approaches by regulatory agencies and by the user based on project objectives, site complexity, unique site features, regulatory requirements, newly developed guidance, newly published scientific research, changes in regulatory criteria, advances in scientific knowledge and technical capability, and unforeseen circumstances. 4.5 Regulatory Frameworks: 4.5.1 This guide is intended to be applicable at a broad range of local, state, tribal, federal (such as CERCLA), or international jurisdictions, each with its own unique regulatory framework. As such, this guide does not provide a detailed discussion of the requirements or guidance associated with any of these regulatory frameworks, nor is it intended to supplant applicable regulations and guidance. The user of this guide will need to be aware of the regulatory requirements and guidance in the jurisdiction where the work is being performed. 4.5.2 Depending on the regulatory requirements in a jurisdiction, the choice of background reference areas may need to consider critical habitats and ecological receptors. 4.6 Systematic Project Planning and Scoping Process: 4.6.1 When applying this guide, the user should undertake a systematic project planning and scoping process to collect information to assist in making site-specific, user-defined decisions for a particular project, including assembling an experienced team of project professionals. These practitioners should have the appropriate expertise to scope, plan, and execute a sediment data acquisition and analysis program. This team may include, but is not limited to, project sponsors, environmental consultants, toxicologists, site remediation professionals, analytical chemists, geochemists, and statisticians. 4.7 Other Considerations: 4.7.1 This guide does not cover all components of a program to develop representative background concentrations for sediment. It is meant to be used in conjunction with other guides (such as Guides E3163 , E3164 , E3240 , E3242 , and E3382 ) to do so. 4.7.2 Sediment sampling and laboratory analyses are not covered in this guide. Guides E3163 and E3164 contain extensive information concerning sediment sampling and laboratory analyses. 4.7.3 Data quality objectives are not covered in this guide. Data quality objectives are described in ( 2 ) . 4.7.4 Background study design considerations are not covered in this guide but are described in other references, including Guide E3163 and ( 3 ) . 4.7.5 The use of data evaluation methodologies to obtain representative background data sets from candidate background data sets is not covered in detail in this guide but is discussed in more depth in Guide E3242 . 4.7.5.1 Identification and removal of high nondetect values from candidate background data sets are discussed in detail in Guide E3242 . 4.7.5.2 Identification and removal of outliers from candidate background data sets are discussed in detail in Practice E178 , as well as Guide E3242 . 4.7.5.3 Geochemical and chemical forensics methodologies used in evaluating candidate background data sets to obtain representative background data sets are discussed in detail in Guide E3242 ; their applications during background reference area selection are discussed in this guide. 4.7.6 The use of statistical methods to develop BTVs from representative background data sets are discussed in detail in Guide E3242 . 4.7.7 The use of statistical methods to compare representative background data sets to sediment site data sets are discussed in detail in Guide E3242 . 4.7.8 Geospatial analysis considerations are not thoroughly discussed in this guidance but are discussed in more depth relative to environmental evaluations in ( 4 ) , which focuses on quality assurance concerns relative to geospatial analyses. 4.7.9 In this guide, sediment ( 3.1.15 ) is defined as material being found at the bottom of a water body. Upland soils of sedimentary origin are excluded from consideration as sediment in this guide. 4.7.10 In this guide, only PCOC concentrations are considered to be in scope. Residual background radioactivity is out of scope. 4.8 Structure and Components of this Guide: 4.8.1 The user of this guide should review the overall structure and components of this guide before proceeding with use, including: Section 1 Scope Section 2 Referenced Documents Section 3 Terminology Section 4 Significance and Use Section 5 Overview of Representative Background Concentrations for Sediment at Sediment Sites and Development Framework Section 6 Background Reference Area Selection Criteria Section 7 Keywords Appendix X1 Case Study References