1.1 沉积物RBCA基于保护人类健康和环境。本指南补充了RBCA（指南 E2081年 )和Eco RBCA（指南 E2205/E2205M )处理并提供受污染沉积物管理的决策过程。受污染沉积物场地在设置、使用、时空复杂性以及物理和化学特征方面存在很大差异；因此，它们可能对人类健康和环境造成的风险也有很大差异。沉积物RBCA通过使用分层方法收集和评估数据来确定是否需要根据现场特定条件和风险进行额外评估或风险管理，从而认识到这种多样性。 1.2 本指南旨在帮助指导和简化纠正行动流程，并补充（但不取代）特定管辖区的指导和法规。它可以在有管辖权的地方使用- 缺乏具体指导或不够详细；当适用重叠管辖区时，它还可以帮助统一指导。它与美国环境保护局（USEPA）、加拿大环境部、欧洲和美国各州的各种风险评估方案指南和指南相兼容，这些国家共享基本的风险评估方法。在所有应用中，应酌情咨询监管机构。沉积物RBCA不适用于当前的许可释放或许可申请。 1.3 有许多TPD与沉积物RBCA过程有关。常见的例子包括定义DQOs、识别相关受体、定义风险评估的毒性值、确定目标风险水平、指定适当的统计数据和样本量、确定暴露假设、确定何时和如何考虑累积风险和相关化学品之间的加性效应、解决资源保护问题、，以及补救行动约束（RAC）。 本指南的目的不是定义适当的TPD。用户应了解特定管辖区的指导，并应寻求批准和/或技术政策输入（如适用）。 1.4 本指南的一般性能标准要求: 1.4.1 TPD将在沉积物RBCA过程的早期确定，并在整个过程中（在每一层）重新评估， 1.4.2 沉积物RBCA过程中收集的数据和信息，包括现场评估期间收集的历史数据和新数据，将与回答问题相关，并具有足够的数量和质量，以支持各级调查的决策， 1.4.3 在基于风险的决策过程中采取的行动将保护人类健康和环境，符合当前的科学原则和实践，并符合管辖区的具体要求（例如，法规、政策和指导），以及 1.4.4 与采取行动之前相比，按照TPD和沉积物RBCA过程实施的补救措施不会导致更大的长期风险。 1.5 所有RBCA指南都有共同的基本要素: 1.5.1 现场评估； 1.5.2 暴露、影响和风险的分层评估； 1.5.3 基于风险的决策； 1.5.4 补救措施，以及 1.5.5 监测。 1.6 本沉积物RBCA侧重于沉积物中化学物质的释放，旨在与指南配套 E1739 , E2081年 和 E2205/E2205M . 指南中讨论了污染场所对人类健康的风险 E1739 和 E2081年 指南中讨论了生态受体的风险 E2205/E2205M 和指南 E2020年 . 1.7 本指南论述了受污染沉积物对人类健康和生态资源的风险。关于进行人类健康和生态风险评估的指南可从各种监管机构、已出版的文献和科学协会获得（见 附录X1 到 附录X7 指导 E2205/E2205M ，和指南 E2020年 ). 1.8 对于需要采取补救行动的现场，提供了制定补救行动目标（RAO）的指导( 附录X7 )支持补救行动计划。 1.9 本指南组织如下: 1.9.1 部分 2. 列出参考的ASTM文件； 1.9.2 部分 3. 定义本指南中使用的术语； 1.9.3 部分 4. 描述了本指南的意义和用途； 1.9.4 部分 5. 描述了沉积物RBCA过程的分层方法； 1.9.5 小节 6. 和 7. 逐步介绍沉积物RBCA程序；和 1.9.6 参考部分列出了本指南中引用的文件。 1.10 本指南还包括以下附录，作为补充信息提供: 1.10.1 附录X1 :沉积物风险评估中证据权重（WOE）方法的设计和执行考虑因素； 1.10.2 附录X2 :在筛选级生态风险评估（SLERAs）中使用沉积物质量指导值（SQG）； 1.10.3 附录X3 :在生态风险评估中推导和使用现场特定生态标准（SSEC）； 1.10.4 附录X4 :风险评估中的不确定性； 1.10.5 附录X5 :参考区域数据在沉积物生态风险评估中的应用； 1.10.6 附录X6 :生物试验方法，以及 1.10.7 附录X7 :开发RAO的指南。 1.11 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。 1.12 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====== 4.1 本指南为在沉积物现场（即沉积物RBCA）选择基于风险的纠正措施提供了一致和透明的决策过程。沉积物RBCA与中描述的其他RBCA具有相同的过程 E1739 , E2081年 和 E2205/E2205M 但明确考虑了现有沉积物评估技术如何影响决策的约束。有几个因素将沉积物场地与高地场地区分开来，并需要进行独特的考虑，包括背景、再污染的可能性、沉积物稳定性、沉积物过程、暴露和运输缺乏控制、暴露路径和受体，以及独特的场地特征，如公共土地、使用和进入缺乏场地控制。沉积物现场可用评估技术的多样性远大于其他介质。其他ASTM指南和监管指南手册中描述了有关技术工具本身的指南。 4.2 沉积物风险资本分析采用了与生态和人类健康风险评估指导文件相同的规划和范围界定、问题制定、暴露和影响评估、风险表征和不确定性分析范式。无论术语如何，沉积物RBCA和风险评估都共享相同的基于科学的过程，并共享相同的目标，即告知风险管理决策。根据管辖要求、现场复杂性、TPD和关于适当使用不同评估技术的最佳专业判断，用于制定基于风险的人类健康和生态标准以及基于风险的管理计划的具体方法可能因现场而异。沉积物RBCA的一些属性包括: 4.2.1 描述分层方法，包括过程流程图，以确定关键步骤并概述整个RBCA过程； 4. 2.2 在整个沉积物RBCA过程中识别、开发和使用TPD； 4.2.3 利益相关者参与的价值和时间指示，认识到一些管辖区需要与各种利益相关者进行不同程度的协调； 4.2.4 识别可能需要或可能不需要进行风险评估的情况； 4.2.5 确定将风险评估结果用作风险管理决策一部分的决策点；和 4.2.6 识别和制定适当的RAO，以支持风险管理。 4.3 本指南中描述的活动应由熟悉场地特征、补救行动科学和技术、人类健康和生态风险评估方法或相关科学和工程主题领域的合格专业人员进行，因为它们与复杂沉积物场地有关。RBCA过程的合理应用通常是多个主题专家的协作。 4.4 为了正确应用沉积物RBCA过程，用户应避免以下情况: 4.4.1 将一级RBSL作为默认补救行动标准，而不考虑通过二级或三级评估开发更精细的RBSL是否合适； 4.4.2 对纠正措施过程施加任意时间限制，这些限制不能反映现场造成的实际紧迫性和风险； 4.4.3 未能记录沉积物RBCA过程的目的（即，根据问题制定要求定义管理目标），并以逻辑和透明的方式将该管理目标与特定评估技术联系起来（即，根据风险评估指南制定一套明确的评估终点和效果度量）； 4.4.4 使用不合理或不适当的暴露因子、毒性参数或评估技术要求的其他假设，或应用现场不支持的模型- 具体数据； 4.4.5 根据不表现出剂量或浓度反应关系的数据开发基于生态的RBSL，或在司法管辖区特定指南要求时未考虑累积风险或附加效应； 4.4.6 在使用RBSL为站点建立RAO时，忽略美学、叙事或其他约束； 4.4.7 在确定现场的适当RAO之前，启动补救行动（而不是为解决紧迫或优先问题而采取的行动）。RAO必须能够使用现有技术（即技术上可行且具有成本效益）实现，并且必须反映沉积物现场在当前和现实的未来现场使用背景下的预期长期结果，以及背景浓度和再污染的可能性。在不考虑现场来源的情况下继续采取补救措施也是不合适的- 控制措施（由于不受控源可能再次污染）。 4.4.8 将补救行动选项限制为单一类型的补救技术，未能考虑补救活动的选项或未能考虑补救技术的使用限制。在所有情况下，都需要进行稳健的补救方案分析，不偏向于特定的补救行动方案； 4.4.9 使用临时补救措施延迟RBCA过程，而不是降低风险； 4.4.10 作为选择过程的一部分，未能考虑潜在补救措施对相关受体的影响； 4.4.11 在选择过程中未能考虑潜在补救措施的长期有效性，或未能在选择和实施后监测选项的有效性；和 4.4.12 一旦达到RAO，继续监测现场（除非RAO明确设计为涉及此类监测）。 （指南 E3164 )

1.1 Sediment-RBCA is based on protecting human health and the environment. The guide supplements the RBCA (Guide E2081 ) and Eco-RBCA (Guide E2205/E2205M ) processes and provides a decision-making process for the management of contaminated sediment. Contaminated sediment sites vary greatly in terms of setting, usage, spatial and temporal complexity, and physical and chemical characteristics; and, therefore, they also vary greatly in terms of the risk that they may pose to human health and the environment. The Sediment-RBCA recognizes this diversity by using a tiered approach for gathering and evaluating data to determine the need for additional evaluation or risk management tailored to site-specific conditions and risks. 1.2 This guide is intended to help direct and streamline the corrective action process and to complement (but not supersede) jurisdiction-specific guidance and regulations. It can be employed where jurisdiction-specific guidance is absent or insufficiently detailed; it can also assist to unify guidance when overlapping jurisdictions apply. It is compatible with a variety of programmatic guidelines for risk assessment and guidance from US Environmental Protection Agency (USEPA), Environment Canada, European, US states, that share the underlying risk assessment approach. In all applications, regulatory agencies should be consulted, as appropriate. Sediment-RBCA is not intended to apply to current permitted releases or permit applications. 1.3 There are numerous TPDs related to the Sediment-RBCA process. Common examples are defining DQOs, identifying relevant receptors, defining toxicity values for risk evaluation, determining target risk levels, specifying the appropriate statistics and sample sizes, determining exposure assumptions, determining when and how to account for cumulative risks and additive effects among chemical(s) of concern, addressing resource protection, along with remedial action constraints (RACs). It is not the intent of this guide to define appropriate TPDs. Users should be aware of jurisdiction-specific guidance and should seek approvals and/or technical policy input as applicable. 1.4 The general performance standard for this guide requires that: 1.4.1 TPDs will be identified early in the Sediment-RBCA process and reevaluated throughout the process (at each tier), 1.4.2 Data and information compiled during the Sediment-RBCA process, including historical data and new data collected during the site assessment, will be relevant to and of sufficient quantity and quality to answer the questions and support the decisions made at each tier of investigation, 1.4.3 Actions taken during the risk-based decision-making process will be protective of human health and the environment, consistent with current scientific principles and practices, and in accordance with jurisdiction-specific requirements (for example, regulations, policies, and guidance), and 1.4.4 Remedial actions implemented consistent with TPDs and the Sediment-RBCA process will not result in greater long-term risks than existed before taking actions. 1.5 There are basic elements common to all RBCA guides: 1.5.1 site assessment; 1.5.2 tiered evaluations of exposure, effects, and risk; 1.5.3 risk-based decision making; 1.5.4 remedial action, and 1.5.5 monitoring. 1.6 This Sediment-RBCA focuses on releases of chemicals from sediment and is intended to be a companion to Guides E1739 , E2081 , and E2205/E2205M . Risks to human health from contaminated sites are discussed in Guides E1739 and E2081 , while risks to ecological receptors are discussed in Guide E2205/E2205M and Guide E2020 . 1.7 Both human health and ecological resource risks from contaminated sediment are addressed in this guide. Guidance on conducting human health and ecological risk assessments is available, including from various regulatory agencies, published literature, and scientific associations (see Appendix X1 to Appendix X7 , Guide E2205/E2205M , and Guide E2020 ). 1.8 For sites that warrant remedial action, guidance is provided on developing remedial Action Objectives (RAOs) ( Appendix X7 ) that support a remedial action plan. 1.9 This guide is organized as follows: 1.9.1 Section 2 lists referenced ASTM documents; 1.9.2 Section 3 defines terminology used in this guide; 1.9.3 Section 4 describes the significance and use of this guide; 1.9.4 Section 5 describes the tiered approach to the Sediment-RBCA process; 1.9.5 Sections 6 and 7 present Sediment-RBCA procedures in a step-by-step process; and 1.9.6 The reference section lists documents cited in this guide. 1.10 This guide also includes the following appendices, which are provided as supplemental information: 1.10.1 Appendix X1 : Considerations for Design and Execution of Weight of Evidence (WOE) Approaches in Sediment Risk Assessment; 1.10.2 Appendix X2 : Use of Sediment Quality Guideline Values (SQGs) in Screening Level Ecological Risk Assessments (SLERAs); 1.10.3 Appendix X3 : Derivation and Use of Site-specific Ecological Criteria (SSEC) in Ecological Risk Assessments; 1.10.4 Appendix X4 : Uncertainty in Risk Evaluation; 1.10.5 Appendix X5 : Application of Reference Area Data in Sediment Ecological Risk Assessment; 1.10.6 Appendix X6 : Biological Test Methods, and 1.10.7 Appendix X7 : Guidance for Developing RAOs. 1.11 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. 1.12 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 This guide provides a consistent and transparent decision-making process for selecting risk-based corrective actions at sediment sites (that is, a Sediment-RBCA). Sediment-RBCA shares the same process as other RBCAs described in E1739 , E2081 , and E2205/E2205M but with explicit consideration of the constraints on how the available sediment assessment techniques impact decision making. Several factors exist that distinguish sediment sites from upland sites and warrant unique consideration, including background, potential for recontamination, sediment stability, sediment processes, lack of control on exposure and transport, exposure pathways and receptors, and unique site characteristics such as public lands, lack of site control on use and access. The diversity of available assessment techniques for a sediment site is considerably larger than for other media. Guidance on the technical tools themselves are described in other ASTM guides and regulatory guidance manuals. 4.2 Sediment-RBCA incorporates the same paradigm of planning and scoping, problem formulation, exposure and effects assessments, risk characterization, and uncertainty analysis that is common to ecological and human health risk assessment guidance documents. Irrespective of terminology, both Sediment-RBCA and risk assessment share the same science-based process and share the same goal of informing risk management decisions. The specific approach used to develop risk-based human health and ecological criteria and risk-based management plans may vary from site to site based on jurisdictional requirements, site complexity, TPDs, and best professional judgment regarding the appropriate use of different assessment techniques. Some attributes of Sediment-RBCA are: 4.2.1 Description of a tiered approach, including process flow charts, to identify critical steps and provide an overview of the entire RBCA process; 4.2.2 Identification, development, and use of TPDs throughout the Sediment-RBCA process; 4.2.3 Indications of the value and timing of stakeholder involvement, recognizing that some jurisdictions require varying degrees of coordination with a variety of stakeholders; 4.2.4 Identification of situations under which a risk assessment may or may not be necessary; 4.2.5 Identification of decision points where risk assessment results are used as part of the risk management decision making; and 4.2.6 Identification and development of appropriate RAOs to support risk management. 4.3 Activities described in this guide should be conducted by qualified professionals familiar with site characterization, remedial action science and technology, human health and ecological risk assessment methodologies, or related scientific and engineering subject areas, as they relate to complex sediment sites. A defensible application of a RBCA process is often a collaboration of multiple subject matter experts. 4.4 To properly apply the Sediment-RBCA process, the user should AVOID the following: 4.4.1 Using Tier 1 RBSLs as a default remedial action standard without considering if proceeding to develop more refined RBSLs through a Tier 2 or Tier 3 evaluation is appropriate; 4.4.2 Placing arbitrary time constraints on the corrective action process that do not reflect the actual urgency and risk posed by the site; 4.4.3 Failing to document the purpose of the Sediment-RBCA process (that is, defining the management goal per the problem formulation requirement) and connecting that management goal to the specific assessment techniques in a logical and transparent way (that is, developing a clear set of assessment endpoints and measures of effects per risk assessment guidance); 4.4.4 Using unjustified or inappropriate exposure factors, toxicity parameters, or other assumptions required by an assessment technique or applying a model that is not supported by site-specific data; 4.4.5 Developing ecologically-based RBSLs from data that do not exhibit a dose- or concentration-response relationship, or failing to consider cumulative risks or additive effects when required to do so by jurisdiction-specific guidance; 4.4.6 Neglecting aesthetic, narrative, or other constraints when using RBSLs to establish the RAOs for a site; 4.4.7 Initiating remedial action(s) (other than an action taken to address imminent or priority issues) before determining the appropriate RAOs for the site. RAOs must be attainable using existing technology (that is, technically practicable and cost effective) and must reflect the desired long-term outcome for a sediment site in the context of current and realistic future site uses, as well as background concentrations and the potential for recontamination. It is also inappropriate to proceed with remedial action(s) without consideration of site source-control measures (due to the potential for recontamination from uncontrolled sources). 4.4.8 Limiting remedial action options to a single type of remedial technology, failing to consider options for remedial activity or failing to consider use limitations of remedial technologies. In all cases, a robust remedial options analysis that is not biased towards a particular remedial action option is needed; 4.4.9 Using an interim remedial action to delay the RBCA process rather than to reduce risk; 4.4.10 Failing to consider the impact of a potential remedial action on relevant receptors as part of the selection process; 4.4.11 Failing to consider the long-term effectiveness of a potential remedial action during the selection process, or failing to monitor the effectiveness of the option once selected and implemented; and 4.4.12 Continuing to monitor a site once the RAOs have been achieved (unless the RAOs were explicitly designed to involve such monitoring). (Guide E3164 )