为了遵守第2阶段消毒剂/消毒副产品（D/DBP）规则 配电系统中消毒副产物（DBP）形成的评估或研究 必修的。本文讨论了两种选择，第一种是评估配电系统中DBP的形成， 称为初始分配系统评估（IDSE），需要一年的时间 总三卤甲烷（TTHM）和五种卤乙酸（HAA5）样品 每隔一个月在配送系统内的八个地点收集一次。顺从 然后根据DBP结果选择样本点。另一个选择是 完成系统特定研究（SSS）。SSS使用历史数据和分布 系统模型或其他方法来评估分销系统并选择 具有代表性的样本位置。IDSE或SSS应在规则颁布后两年到期。 IDSE要求适用于所有服务于1万吨及以上人口的公共供水系统 使用受地表水影响（GWUI）的地表水或地下水 根据地表水处理规则的要求。IDSE 要求也适用于使用主要消毒剂的地下水系统 比紫外线（UV）或添加残留的消毒剂到他们的水，或系统，提供这样的水。 美国环境保护局（USEPA）制定了第2阶段消毒剂和消毒副产品规则草案 初始分配系统评估指导手册（美国环保局2001）可供 公开审查。尽管仍处于草稿阶段，但手册涵盖了所有行业的IDSE要求 系统类型和大小。以下是IDSE需求摘要的详细信息 报告可在指南手册草案中找到。 已制定了具体要求，以满足使用 液压分配系统模型。这些指南仅针对水力建模 不涉及分配系统水质模型。集成液压系统 而水质分配系统模型可以提供更好的信息 分布式数据库环境中的信息系统。与所有SSS一样，一个集成的 水力和水质分配系统模型必须提供等效或 与系统监控计划（SMP）相比，选址信息更优越。为满足SSS的要求，液压和水质组件 综合配送系统的设计必须详细、全面、完善 校准。了解这些组件的功能非常重要 以达到理解配电系统中DBP形成的目标 环境水力模型模拟配水系统中的水运动，以 了解水龄、需求模式和压力。水质模型估计 根据工厂处理工艺或 配电系统状况。与IDSE特别相关的是，水质模型可以 确定消毒残留物和消毒副产品的浓度。 SSS的主要目标是让公用事业公司更好地了解 供水系统的水力和水质。这是一个可以用来 识别配电系统中的故障点。此外，生成的模型是 强大的规划工具，可用于预测分布中DBP的形成 建议修改的系统。最后，本实用新型允许该实用程序改进其功能 运营和彻底评估每个现场的备选方案 避免代价高昂的全系统资本变动，如实施 氯胺化以减少配电系统中DBP的形成。 出于这些原因，黄金城选择采用SSS合规方法。 本文重点介绍了执行全面SSS所采取的步骤，特别是

In order to comply with the Stage 2 Disinfectant/Disinfection Byproduct (D/DBP) Rule, an evaluation or study of disinfection byproduct (DBP) formation in the distribution system is required. This paper discusses two options, the first being an evaluation of DBP formation in the distribution system, called an Initial Distribution System Evaluation (IDSE), that requires that one year of paired total trihalomethane (TTHM) and the five haloacetic acid species (HAA5) samples be collected every other month at eight locations within the distribution system. Compliance sample sites are then selected based on the DBP results. The other option is to complete a System-Specific-Study (SSS). An SSS uses historical data, distribution system models or other methods to assess the distribution system and select representative sample locations. The IDSE or SSS is due two years after rule promulgation. IDSE requirements apply to all public water systems serving a population of >10,000 and using surface water or groundwater under the influence (GWUI) of surface water that are subject to the requirements of the Surface Water Treatment Rule. The IDSE requirements also apply to groundwater systems that use a primary disinfectant other than ultraviolet (UV) or add a residual disinfectant to their water, or systems that deliver such water. The US Environmental Protection Agency (USEPA) has made the Draft Stage 2 Disinfectants and Disinfection Byproducts Rule Initial Distribution System Evaluation Guidance Manual (USEPA 2001) available to the public for review. While still in draft form, the manual covers IDSE requirements for all system types and sizes. Details of the IDSE requirements summary that follows in this report can be found in the draft guidance manual. Specific requirements have been developed to meet the requirements for a SSS using a hydraulic distribution system model. These guidelines address only hydraulic modeling and do not address distribution system water quality models. An integrated hydraulic and water quality distribution system model may provide even better information about DBP formation in distribution system environments. As with all SSSs, an integrated hydraulic and water quality distribution system model must provide equivalent or superior information for site selection than a system monitoring plan (SMP). To meet the requirements of the SSS, both the hydraulic and water quality components of the integrated distribution system must be detailed, comprehensive, and well calibrated. It is important to understand how each of these components function individually to meet the goal of understanding DBP formation in a distribution system environment. Hydraulic models simulate water movement in a distribution system to understand water age, demand patterns, and pressure. Water quality models estimate changes in source and treated water quality based on plant treatment processes or distribution system conditions. Specifically related to the IDSE, water quality models can characterize disinfection residual and disinfection byproduct concentrations. The main objective of a SSS is to allow utilities to gain a better understanding of the hydraulics and water quality in their distribution system. It is a tool that can be used to identify trouble spots within the distribution system. In addition, the resulting model is a powerful planning tool that can be used to predict DBP formation in the distribution system for proposed modifications. Finally, the model allows the utility to refine its operations and thoroughly evaluated alternatives on a site-by-site basis potentially avoiding costly system-wide capital changes such as the implementation of chloramination in order to decrease the formation of DBPs in the distribution system. For these reasons, the City of Golden elected to pursue the SSS compliance approach. This paper focuses on the steps taken to perform a full-scale SSS, specifically