1.1 这是在保护人类健康和环境的基础上，在化学品释放场所实施基于风险的纠正措施（RBCA）的指南。RBCA是评估和应对化学品释放的一致决策过程。化学品释放地点在复杂性、物理和化学特性以及可能对人类健康和环境造成的风险方面存在很大差异。RBCA过程通过使用分层方法来识别这种多样性，该方法将现场评估和响应行动与人类健康和生态风险评估相结合，以确定补救行动的必要性，并根据现场具体情况和风险量身定制纠正行动活动。RBCA过程中使用的评估和方法从第1层中的简单分析开始，然后转移到第2层或第3层中更复杂的评估（如适用）。 收集和评估数据的过程是按比例进行的。因此，仅在该层收集特定层决策所需的数据。 1.2 本指南描述了基于风险的纠正措施的方法。其目的是帮助指导和简化纠正措施流程，补充但不是取代联邦、州和地方法规。它可用于正在采取纠正措施的现场，包括可能没有纠正措施监管框架的现场，或用户希望采取纠正措施的现场，如自愿清理计划或棕地倡议下的现场。此外，当几个不同的代理程序影响站点时，它也可以用作统一框架。此外，用户应了解适用于现场的联邦、州和地方纠正行动计划，无论该计划如何，实施本指南中概述的流程可能需要联邦、州和地方机构的批准。 最后，无论纠正措施是否由监管计划具体管理，用户都应咨询监管机构的要求，以在实施RBCA流程之前确定适当的技术政策决策。 1.3 为了实施RBCA流程，必须做出许多技术政策决策，例如，定义数据质量目标，确定目标风险水平，指定用于计算暴露浓度的适当统计数据和样本量，选择暴露假设，确定何时以及如何考虑相关化学品之间的累积风险和附加效应，并解决资源保护问题。本指南的目的不是定义适当的技术政策决策。用户必须确定适当的技术政策决策。 1.4 本指南的一般性能标准要求: 1.4.1 在开始过程之前确定技术政策决策， 1.4.2 RBCA过程中收集的数据和信息，包括历史数据以及现场评估期间收集的新数据，将与RBCA过程中提出的问题和将要作出的决定相关，并具有足够的数量和质量， 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， 1.4.4 将遵循适用的联邦、州和地方法规（例如，废物管理要求、地下水指定、工人保护）和， 1.4.5 实施的补救措施不会导致比采取措施前更高的风险水平。 1.5 ASTM标准不是联邦或州法规，它们是可以自愿遵循的共识标准。 1.6 RBCA过程不限于特定类别的化合物。 本指南旨在与指南配套使用 E1739 ，并不会取代该文件的石油发布。如果释放场所包含石油和其他化学品的混合物，则应遵循本指南。 1.7 美国环境保护局（USEPA）制定了人类健康风险评估指南（见 附录X9 其他资源）。本指南的许多组成部分已整合到RBCA框架中。然而，生态评估科学及其应用过程并不像人类健康风险评估那样得到良好定义和认可。因此，本指南中为相关生态受体和栖息地的各级评估提供的信息是一般性的。用户是指 附录X5 ，它提供了有关制定保护生态资源的RBCA框架的更多信息。 1.8 本指南中描述的决策过程将暴露和风险评估实践与现场评估活动和补救行动选择相结合，以确保所选行动保护人类健康和环境。RBCA中规定了以下一般事件顺序: 1.8.1 执行初始现场评估，并开发现场概念模型的第一次迭代（见指南 E1689 和 E3240 和ISO 21365:2019）。如果信息足以证明不存在完整或潜在完整的暴露途径，则无需采取进一步行动， 1.8.2 评估现场（见现场定义 3.2.50 )对于响应行动（单个设施的多个站点可能需要不同的响应行动和时间）， 1.8.3 实施适合现场响应行动评估期间现场条件的响应行动， 1.8.4 定义数据要求，制定数据质量目标，并在现场概念模型表明分层评估合适的情况下，对一级评估进行现场评估， 1.8.5 进行接触途径分析，以确定是否存在相关的生态受体和栖息地，以及是否存在完整和潜在完整的接触途径。如果不存在相关的生态受体或栖息地或完整且可能完整的暴露途径，则无需对相关的生态受体和栖息地采取进一步行动， 1.8.6 对于潜在的人类暴露途径，确定适用的基于风险的筛查水平（RBSL），对于潜在的生态暴露途径，确定适用的相关生态筛查标准（RESC）。此外，确定任何其他相关的可测量标准（ORMC）（如适用）。这些是现场的1级纠正行动目标； 1.8.7 将现场条件与确定适用于现场的一级纠正措施目标进行比较； 1.8.8 如果现场条件满足相关化学品的纠正措施目标，则无需采取进一步措施， 1.8.9 如果现场条件不符合相关化学品的纠正措施目标，则应采取以下一项或多项措施: 1.8.9.1 进一步分层评估； 1.8.9.2 实施临时补救措施； 1.8.9.3 设计并实施补救措施，以实现纠正措施目标。 1.8.10 定义二级数据要求、数据质量目标，收集额外的现场特定信息，并在必要时更新现场概念模型（如果需要进一步的二级评估）， 1.8.11 根据现场特定目标水平（SSTL）、现场特定生态标准（SSEC）或ORMC（如适用），为完整和潜在完整的暴露途径，包括未确定RBSL、RESC或ORMC（如适用）的暴露途径，制定示范点和二级纠正行动目标； 1.8.12 将现场条件与确定适用于现场的二级纠正措施目标进行比较； 1.8.13 如果现场条件满足相关化学品的纠正行动目标，则无需采取进一步行动， 1.8.14 如果现场条件不符合相关化学品的纠正措施目标，则应采取以下一项或多项措施: 1.8.14.1 进一步分层评估； 1.8.14.2 实施临时补救措施； 1.8.14.3 设计并实施补救措施，以实现纠正措施目标。 1.8.15 定义三级数据要求、数据质量目标，收集额外的现场特定信息，并在必要时更新现场概念模型（如果需要进一步的三级评估）， 1.8.16 酌情根据SSTL、SSEC或ORMC制定示范点和第3级纠正行动目标； 1.8.17 将现场条件与三级纠正措施目标进行比较， 1.8.18 如果现场条件满足相关化学品的纠正行动目标，则无需采取进一步行动， 1.8.19 如果现场条件不符合相关化学品的纠正措施目标，则应采取以下措施之一: 1.8.19.1 实施临时补救措施，以促进对等级评估的重新评估； 1.8.19.2 设计并实施补救措施，以实现纠正措施目标。 1.8.20 根据纠正行动目标制定并实施监测计划，以验证用于分层评估的假设，并证明纠正行动的有效性（如适用）。 1.9 对于目前正在采取纠正措施的化学品释放场所，用户应审查该场所可用的信息和数据，并根据本指南中概述的一般性能标准和事件顺序，确定进入RBCA框架的最合适入口点。 1.10 本指南组织如下- 部分 2. 列出参考文件，章节 3. 定义本指南第节中使用的术语 4. 介绍本指南第节的意义和使用 5. 是分层方法的摘要，以及第节 6. 逐步介绍RBCA程序。 附录X1 为制定技术政策决策和建立RBCA计划提供指导， 附录X2 提供可能有助于RBCA评估的化学性质和效应数据示例， 附录X3 提供了RBSL的开发示例， 附录X4 描述了预测建模的使用， 附录X5 概述了生态评估过程， 附录X6 提供有关活动和使用限制的信息， 附录X7 包括RBCA框架应用的示例， 附录X8 含氟和多氟烷基物质的地址( PFAS ). 全氟辛烷磺酸是一种合成化学品，不会在环境中自然产生。全氟辛烷磺酸有许多不同类型，例如全氟羧酸（例如，全氟辛烷磺酸，有时称为C8和PFNA）和全氟磺酸（例如，全氟辛烷磺酸和全氟辛烷磺酸），以及 附录X9 包括可能对用户有帮助的参考资料。 注1: 附录X8 以华盛顿生态部的基于风险的纠正措施方法为例；包括阿拉斯加州、加利福尼亚州、科罗拉多州、缅因州、马萨诸塞州、密歇根州、明尼苏达州、新罕布什尔州、新泽西州、纽约州、宾夕法尼亚州、罗得岛州和佛蒙特州在内的许多其他州都制定了强有力的计划，以解决向环境排放PFA的问题。 附录仅供参考，不作为本指南的强制性章节。 1.11 以国际单位制表示的数值应视为标准值。 本标准不包括其他计量单位。 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 本指南中提出的基于风险的纠正措施（RBCA）过程是一个一致、简化的决策过程，用于在化学品释放场所选择纠正措施。 4.2 风险评估是一门发展中的科学。由于监管要求、指导和替代科学方法的使用，用于开发RBSL和SSTL的科学方法可能因监管机构和用户而异。 4.3 本指南中描述的活动应由熟悉当前现场特征描述技术、补救行动科学和技术、当前人类健康风险和暴露评估方法、毒理学和当前生态评估方法的人员进行。 4.4 为了正确应用RBCA过程，用户应该 避免 以下内容: 4.4.1 将一级RBSL或RESC规定为所有站点的补救行动标准，而不是筛查水平， 4.4.2 将RBCA过程的使用仅限于一级评估，而不继续对适合进一步二级评估的站点进行二级或三级分析， 4.4.3 对纠正措施过程施加任意时间约束；例如，要求在不反映现场实际紧迫性和风险的时间段内完成第1、2和3层， 4.4.4 只有当积极的补救措施在技术上不可行时，才使用RBCA过程，而不是作为一个适用于纠正措施所有阶段的过程， 4.4.5 在确定适用的纠正行动目标之前，采取积极的补救行动，以仅达到基于技术的补救限制（例如，渐进水平）， 4.4.6 使用可用数据或现场条件知识不支持的预测建模， 4.4.7 将补救措施选项限制为所有现场的单一补救措施类别（例如指南 E1943 ), 4.4.8 使用不合理或不适当的暴露因素， 4.4.9 使用不合理或不适当的毒性参数， 4.4.10 在评估多种化学品时，未能考虑累积风险和附加效应， 4.4.11 不包括对活动选项和使用限制、暴露点、演示点、同一设施多个地点补救行动活动排序或风险水平的评估， 4.4.12 不包括活动和使用限制的维护和监控， 4.4.13 未能考虑潜在补救行动方案的长期有效性和可靠性， 4.4.14 未能评估拟议补救措施或评估方法可能对公众、工人以及相关生态受体和栖息地造成的潜在风险，以及 4.4.15 在已实现纠正措施目标的现场继续监测或补救措施（除非活动和使用限制或其他监管要求特别要求监测）。纠正措施目标的实现取决于足够的监测，以证实现场条件。 4.5 本指南中描述的RBCA流程包括几个功能，这些功能只是解决特定活动目标的标准化方法的示例，例如，响应行动评估表和暴露场景评估流程图。这些要素应由用户根据所处理的站点或站点组的约束条件和适当的技术政策决策进行定制。本指南确定了分析的目标。

1.1 This is a guide for conducting risk-based corrective action (RBCA) at chemical release sites based on protecting human health and the environment. The RBCA is a consistent decision-making process for the assessment and response to chemical releases. Chemical release sites vary greatly in terms of complexity, physical and chemical characteristics, and in the risk that they may pose to human health and the environment. The RBCA process recognizes this diversity by using a tiered approach that integrates site assessment and response actions with human health and ecological risk assessment to determine the need for remedial action and to tailor corrective action activities to site-specific conditions and risks. The evaluations and methods used in the RBCA process begin with simple analyses in Tier 1 and move to more complex evaluations in either Tier 2 or Tier 3, as applicable. The process of gathering and evaluating data is conducted in a scaled fashion. Consequently, only the data that are necessary for a particular tier's decision-making are collected at that tier. 1.2 This guide describes an approach for risk-based corrective action. It is intended to help direct and streamline the corrective action process and to complement but not to supersede federal, state and local regulations. It can be employed at sites where corrective action is being conducted including sites where there may not be a regulatory framework for corrective action, or where the user wishes to conduct corrective action such as sites in voluntary cleanup programs or under Brownfields initiatives. In addition, it can also be used as a unifying framework when several different agency programs affect the site. Furthermore, the user should be aware of the federal, state and local corrective action programs that are applicable for the site and, regardless of the program, federal, state and local agency approvals may be required to implement the processes outlined in this guide. Finally, regardless of whether a corrective action is specifically governed by a regulatory program, the user should consult the regulatory agency requirements to identify the appropriate technical policy decisions prior to implementing the RBCA process. 1.3 There are numerous technical policy decisions that must be made to implement the RBCA process, for example, defining data quality objectives, determining target risk levels, specifying the appropriate statistics and sample sizes for calculating exposure concentrations, selection of exposure assumptions, determining when and how to account for cumulative risks and additive effects among chemical(s) of concern and addressing resource protection. It is not the intent of this guide to define appropriate technical policy decisions. The user must identify the appropriate technical policy decisions. 1.4 The general performance standard for this guide requires that: 1.4.1 Technical policy decisions be identified before beginning the process, 1.4.2 Data and information collected during the RBCA process, including historical data as well as new data collected during the site assessment, will be relevant to and of sufficient quantity and quality to answer the questions posed by and the decisions to be made in the RBCA process, 1.4.3 Actions taken during the risk-based decision process will be protective of human health and the environment, 1.4.4 Applicable federal, state and local regulations will be followed (for example, waste management requirements, ground water designations, worker protection) and, 1.4.5 Remedial actions implemented will not result in higher risk levels than existed before taking actions. 1.5 ASTM standards are not federal or state regulations, they are consensus standards that can voluntarily be followed. 1.6 The RBCA process is not limited to a particular class of compounds. This guide is intended to be a companion to Guide E1739 , and does not supersede that document for petroleum releases. If a release site contains a mixture of releases of petroleum and other chemicals, this guide should be followed. 1.7 The United States Environmental Protection Agency (USEPA) has developed guidance for human health risk evaluation (see Appendix X9 for other resources). Many of the components of this guidance have been integrated into the RBCA framework. The science of ecological evaluation and the process by which the science is applied, however, are not as well defined and agreed upon as human health risk assessment. Therefore, the information provided in this guide for each tier evaluation for relevant ecological receptors and habitats is general. The user is referred to Appendix X5 , which provides additional information regarding the development of a RBCA framework for protection of ecological resources. 1.8 The decision process described in this guide integrates exposure and risk assessment practices with site assessment activities and remedial action selection to ensure that the chosen actions are protective of human health and the environment. The following general sequence of events is prescribed in RBCA: 1.8.1 Perform an initial site assessment and develop the first iteration of the site conceptual model (see Guides E1689 and E3240 and ISO 21365:2019). If the information is sufficient to demonstrate that there are no complete or potentially complete exposure pathways, then no further action is warranted, 1.8.2 Evaluate the site (see definition of site 3.2.50 ) for response actions (multiple sites at a single facility may require different response actions and times), 1.8.3 Implement a response action that is appropriate for conditions found at the site during the site response action evaluation, 1.8.4 Define data requirements, develop data quality objectives, and perform a site assessment for the Tier 1 evaluation if the site conceptual model indicates that the tiered evaluation is appropriate, 1.8.5 Conduct an exposure pathway analysis to determine if relevant ecological receptors and habitats are present and if complete and potentially complete exposure pathways are present. If no relevant ecological receptors or habitats or complete and potentially complete exposure pathways exist, then no further action for relevant ecological receptors and habitats is warranted, 1.8.6 For potential human exposure pathways, identify the applicable Risk Based Screening Levels (RBSL) and for potential ecological exposure pathways, identify the applicable Relevant Ecological Screening Criteria (RESC). In addition, identify any Other Relevant Measurable Criteria (ORMC), as applicable. Collectively these are the Tier 1 corrective action goals for the site; 1.8.7 Compare site conditions to the Tier 1 corrective action goals determined to be applicable to the site; 1.8.8 If site conditions meet the corrective action goals for chemical(s) of concern then, no further action is warranted, 1.8.9 If site conditions do not meet corrective action goals for chemical(s) of concern then, one or more of the following actions is appropriate: 1.8.9.1 Further tier evaluation; 1.8.9.2 Implement interim remedial action; 1.8.9.3 Design and implement remedial action to achieve the corrective action goals. 1.8.10 Define Tier 2 data requirements, data quality objectives, collect additional site-specific information and update the site conceptual model, as necessary, if further tier evaluation is warranted, 1.8.11 Develop point(s) of demonstration and Tier 2 corrective action goals based on Site-Specific Target Levels (SSTL), Site-Specific Ecological Criteria (SSEC) or ORMC, where appropriate, for complete and potentially complete exposure pathways, including exposure pathways for which no RBSL, RESC or ORMC, as applicable, were determined; 1.8.12 Compare site conditions to the Tier 2 corrective action goals determined to be applicable to the site; 1.8.13 If site conditions meet corrective action goals for chemical(s) of concern, then no further action is warranted, 1.8.14 If site conditions do not meet corrective action goals for chemical(s) of concern then, one or more of the following actions is appropriate: 1.8.14.1 Further tier evaluation; 1.8.14.2 Implement interim remedial action; 1.8.14.3 Design and implement remedial action to achieve the corrective action goals. 1.8.15 Define Tier 3 data requirements, data quality objectives and collect additional site-specific information and update the site conceptual model, as necessary, if further tier evaluation is warranted, 1.8.16 Develop point(s) of demonstration and Tier 3 corrective action goals based on SSTL, SSEC, or ORMC, where appropriate; 1.8.17 Compare site conditions to the Tier 3 corrective action goals, 1.8.18 If site conditions meet corrective action goals for chemical(s) of concern, then no further action is warranted, 1.8.19 If site conditions do not meet corrective action goals for chemical(s) of concern, then one of the following actions is appropriate: 1.8.19.1 Implement interim remedial action to facilitate reassessment of the tier evaluation; 1.8.19.2 Design and implement remedial action to achieve the corrective action goals. 1.8.20 Develop and implement a monitoring plan based on the corrective action goals to validate the assumptions used for the tier evaluation and to demonstrate effectiveness of the remedial action, as applicable. 1.9 For chemical release sites currently in corrective action, the user should review information and data available for the site and determine the most appropriate entry point into the RBCA framework consistent with the general performance standards and sequence of events outlined in this guide. 1.10 This Guide is Organized as Follows— Section 2 lists referenced documents, Section 3 defines terminology used in this guide, Section 4 describes the significance and use of this guide, Section 5 is a summary of the tiered approach, and Section 6 presents the RBCA procedures in a step-by-step process. Appendix X1 provides guidance on developing technical policy decisions and building a RBCA program, Appendix X2 provides examples of chemical properties and effects data that may be useful for a RBCA evaluation, Appendix X3 provides EXAMPLE development of RBSL, Appendix X4 describes the use of predictive modeling, Appendix X5 provides an outline of the process of the ecological evaluation, Appendix X6 provides information about activity and use limitations, Appendix X7 includes illustrative examples of the application of the RBCA framework, Appendix X8 addresses Per- and polyfluoroalkyl substances ( PFAS ). PFAS are synthetic chemicals that do not occur naturally in the environment. There are many different types of PFAS such as perfluorocarboxylic acids (for example, PFOA, sometimes called C8, and PFNA) and perfluorosulfonates (for example, PFOS and PFHxS), and Appendix X9 includes references that may be helpful to the user. Note 1: Appendix X8 references the Washington Department of Ecology’s risk-based corrective action approach to PFAS as an example; numerous other states including Alaska, California, Colorado, Maine, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont have robust programs to address releases of PFAS to the environment. The appendixes are provided for additional information and are NOT included as mandatory sections of this guide. 1.11 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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 The risk-based corrective action (RBCA) process presented in this guide is a consistent, streamlined decision process for selecting corrective actions at chemical release sites. 4.2 Risk assessment is a developing science. The scientific approach used to develop the RBSL and SSTL may vary by regulatory agency and by user due to regulatory requirements, guidance and use of alternative scientifically-based methods. 4.3 Activities described in this guide should be conducted by persons familiar with current site characterization techniques, remedial action science and technology, current human health risk and exposure assessment methodologies, toxicology, and current ecological evaluation methodologies. 4.4 In order to properly apply the RBCA process, the user should AVOID the following: 4.4.1 Prescribing Tier 1 RBSL or RESC as remedial action standards for all sites rather than screening levels, 4.4.2 Limiting use of the RBCA process to Tier 1 evaluation only and not continuing with Tier 2 or Tier 3 analyses for sites where further tier evaluation is appropriate, 4.4.3 Placing arbitrary time constraints on the corrective action process; for example, requiring that Tiers 1, 2, and 3 be completed within time periods that do not reflect the actual urgency of and risks posed by the site, 4.4.4 Using the RBCA process only when active remedial action is not technically feasible, rather than as a process that is applicable during all phases of corrective action, 4.4.5 Conducting active remedial action to achieve only technology-based remedial limits (for example, asymptotic levels) prior to determining applicable corrective action goals, 4.4.6 Using predictive modeling that is not supported by available data or knowledge of site conditions, 4.4.7 Limiting remedial action options to a single class of remedial actions for all sites (for example Guide E1943 ), 4.4.8 Using unjustified or inappropriate exposure factors, 4.4.9 Using unjustified or inappropriate toxicity parameters, 4.4.10 Failing to consider cumulative risks and additive effects when evaluating multiple chemicals, 4.4.11 Excluding the evaluation of options for activity and use limitations, point(s) of exposure, point(s) of demonstration, sequencing remedial action activities at multiple sites on the same facility, or risk levels, 4.4.12 Excluding the maintenance and monitoring of activity and use limitations, 4.4.13 Failing to consider the long-term effectiveness and reliability of potential remedial action options, 4.4.14 Failing to evaluate potential risks to the public, to workers and to relevant ecological receptors and habitats that may be created by proposed remedial actions or assessment methods and 4.4.15 Continuing monitoring or remedial action at sites that have achieved the corrective action goals (unless monitoring is specifically required for an activity and use limitation or another regulatory requirement). Achievement of corrective action goals is predicated on sufficient monitoring to substantiate the site conditions. 4.5 The RBCA process described in this guide includes several features that are only examples of standardized approaches to addressing the objectives of the particular activity, for example, the response action evaluation table and the exposure scenario evaluation flowchart. These elements should be customized by the user based on the constraints of the site or group of sites being addressed and the appropriate technical policy decisions. The objectives of the analyses are identified in this guide.