1.1 本指南涵盖了确定地下水建模项目中使用的计算机代码的要求和选择的系统方法。由于地下流体流动以及生物和化学运输的复杂性，存在许多不同的地下水建模代码，每个代码都有特定的能力和局限性。此外，在使用地下水模型的项目中，可能会遇到各种各样的情况。为特定应用程序确定最合适的代码需要对手头的问题以及所需和可用的资源进行彻底分析，并详细描述候选代码的功能。 1.2 本指南中描述的代码选择过程包括系统分析项目需求和仔细评估项目需求与候选代码能力之间的匹配。候选代码的功能记录不足，可能需要对代码功能进行额外分析，作为代码选择过程的一部分。 图1 用于帮助确定项目在代码能力方面的需求，并在必要时确定代码能力。 1.3 本指南是关于地下水建模代码及其应用的一系列指南之一，例如指南 D5447 , D5490 , D5609 , D5610 , D5611 , D5718 和 D6025 . 1.4 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。本指南不能取代教育或经验，应与专业判断结合使用。并非本指南的所有方面都适用于所有情况。本指南无意代表或取代必须根据其判断特定专业服务是否充分的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本指南。 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。 1.5 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和健康实践，并确定监管限制的适用性。 ====意义和用途====== 4.1 地下水建模已成为支持地下水管理规划和决策过程的重要方法。 地下水模型提供了一个分析框架，用于了解地下水系统的机制和控制以及影响其质量的过程，尤其是人为干预此类系统引起的过程。模型越来越多地成为水资源评估、保护和恢复研究的一个组成部分，并为规划和筛选影响地下水的替代政策、法规和工程设计提供必要且具有成本效益的支持。 4. 4.2 有许多不同的地下水建模代码可用，每个代码都有自己的功能、操作特点和局限性。 此外，每个地下水项目在建模方面都有自己的要求。因此，为特定项目选择最合适的代码是很重要的。对于需要广泛建模的项目，或者部分基于基于建模的分析结果的昂贵决策的项目，这一点更为重要。 4.3 对项目要求和代码特征的系统和全面描述为高效选择地下水建模代码提供了必要的基础。本标准指南旨在鼓励对代码选择过程中的代码能力和代码要求进行全面、一致的描述，以及对代码选择过程进行全面的记录。

1.1 This guide covers a systematic approach to the determination of the requirements for and the selection of computer codes used in a groundwater modeling project. Due to the complex nature of fluid flow and biotic and chemical transport in the subsurface, many different groundwater modeling codes exist, each having specific capabilities and limitations. Furthermore, a wide variety of situations may be encountered in projects where groundwater models are used. Determining the most appropriate code for a particular application requires a thorough analysis of the problem at hand and the required and available resources, as well as detailed description of the functionality of candidate codes. 1.2 The code selection process described in this guide consists of systematic analysis of project requirements and careful evaluation of the match between project needs and the capabilities of candidate codes. Insufficiently documented capabilities of candidate codes may require additional analysis of code functionality as part of the code selection process. Fig. 1 is provided to assist with the determination of project needs in terms of code capabilities, and, if necessary, to determine code capabilities. 1.3 This guide is one of a series of guides on groundwater modeling codes and their applications, such as Guides D5447 , D5490 , D5609 , D5610 , D5611 , D5718 , and D6025 . 1.4 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This guide cannot replace education or experience and should be used in conjunction with professional judgement. Not all aspects of this guide may be applicable in all circumstances. This guide 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 guide 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. 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 and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 4.1 Groundwater modeling has become an important methodology in support of the planning and decision-making processes involved in groundwater management. Groundwater models provide an analytical framework for obtaining an understanding of the mechanisms and controls of groundwater systems and the processes that influence their quality, especially those caused by human intervention in such systems. Increasingly, models are an integral part of water resources assessment, protection, and restoration studies, and provide needed and cost-effective support for planning and screening of alternative policies, regulations, and engineering designs affecting groundwater. 4 4.2 Many different groundwater modeling codes are available, each with their own capabilities, operational characteristics and limitations. Furthermore, each groundwater project has its own requirements with respect to modeling. Therefore, it is important that the most appropriate code is selected for a particular project. This is even more important for projects that require extensive modeling, or where costly decisions are based, in part, on the outcome of modeling-based analysis. 4.3 Systematic and comprehensive description of project requirements and code features provides the necessary basis for efficient selection of a groundwater modeling code. This standard guide is intended to encourage comprehensive and consistent description of code capabilities and code requirements in the code selection process, as well as thorough documentation of the code selection process.