1.1 本规程涵盖了一种分析程序，用于确定承压含水层的透射率和蓄水系数，同时考虑上覆或下覆封闭层或两者中的蓄水量变化。本规程用于分析在以恒定速率从控制井抽水期间从一个或多个观察井或测压计收集的水位或水头数据。随着符号的适当变化，这种做法也可用于分析以恒定速率向控制井注水的效果。 1.2 该分析程序与试验方法一起使用 D4050 . 1.3 限制- 改进的Hantush方法的有效使用 ( 1. ) 2. 仅限于确定水文地质环境中含水层的水力特性，并与Hantush-Jacob方法（实践）的假设合理对应 D6029/D6029M )例外情况是，在这种情况下，考虑了封闭层中蓄水的得失（见 5.1 ). 所有可能的不透水层和源层组合（例如，水头保持均匀的层）均考虑在限制相关含水层的渗漏层的远侧（见 图1 ). 图1 通过渗漏含水层中排水井的横截面，在封闭层中储存水，说明了边界条件的三种不同情况（来自Reed）( 2. ) ) 1.4 所有观察值和计算值应符合实践中确定的有效数字和舍入准则 D6026 . 1.4.1 用于规定如何在标准中收集/记录和计算数据的程序被视为行业标准。此外，它们代表了通常应保留的有效数字。使用的程序不考虑材料变化、获取数据的目的、特殊目的研究或用户目标的任何考虑因素； 通常的做法是增加或减少报告数据的有效位数，以与这些考虑因素相称。考虑工程数据分析方法中使用的有效数字超出了这些测试方法的范围。 1.5 以国际单位制或英寸-磅单位表示的数值应单独视为标准值。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。两个系统的组合值可能会导致不符合标准。以国际单位制以外的单位报告结果不应视为不符合本标准。 1.6 本实践提供了一组用于执行一个或多个特定操作的说明。本文件不能取代教育或经验，应与专业判断一起使用。并非实践的所有方面都适用于所有情况。 本ASTM标准不代表或取代必须根据其判断给定专业服务的充分性的谨慎标准，也不应在不考虑项目的许多独特方面的情况下应用本文件。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。 1.7 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。 1.8 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====== 5.1 假设: 5.1.1 控制井以恒定速率排放， Q . 5.1.2 控制井直径无限小，完全穿透含水层。 5.1.3 含水层是均质、各向同性的，区域广泛。 注1: 段塞和泵送试验隐含假设为多孔介质。断裂岩石和碳酸盐岩环境可能无法提供有意义的数据和信息。 5.1.4 含水层保持饱和（即水位不会下降到含水层顶部以下）。 5.1.5 含水层通过单独具有均匀水力传导率、特定蓄水量和厚度的封闭层覆盖或覆盖，或两者兼有。封隔层在远侧由图1所示的一种情况所包围 图1 . 5.1.6 含水层中的水流是二维的，在水平面呈径向。 5.2 井和含水层系统的几何形状如所示 图1 . 5.3 假设的含义: 5.3.1 段落 5.1.1 表明控制井的排放速率恒定。段落 8.1 试验方法 D4050 讨论了可接受的严格恒定速率的变化。除非加以考虑，否则流量变化的连续趋势可能会导致对水位变化数据的误解。 注2: 本标准产生的结果的质量取决于执行该标准的人员的能力，以及所用设备和设施的适用性。符合实践标准的机构 D3740 通常认为能够胜任和客观的测试/采样/检查等。本标准的用户应注意遵守惯例 D3740 本身并不能保证可靠的结果。可靠的结果取决于许多因素；实践 D3740 提供了一种评估其中一些因素的方法。 5.3.2 改进的Hantush方法考虑的泄漏约束层问题要求控制井具有无穷小的直径且没有储层。Moench公司 ( 6. ) 推广了改进的Hantush方法解决的现场情况 ( 1. ) 将井筒蓄能包括在泵井中的方法。他用于获得更一般问题的解的数学方法导致拉普拉斯变换解，其解析反演尚未开发，如果可能的话，评估可能会非常复杂。Moench公司 ( 6. ) 使用数值拉普拉斯反演算法为选定情况绘制类型曲线。Moench考虑的情况表明，大型井筒储存可能会掩盖因限制层储存变化而产生的泄漏影响。未明确给出导致这种掩蔽的含水层和限制层特性以及井半径的特定组合。 然而，Moench( ( 6. ) ，第1125页）指出，“因此，对于给定的井径，当含水层透过率 Kb 和存储系数 S s b 都很小。”Moench（第1129页）指出，“减少或有效消除井筒蓄水掩盖效应的一种方法是用液压封隔器隔离相关含水层，并在加压条件下重复泵试验。因为井筒蓄水 C 这将是由于流体的可压缩性，而不是改变井中的水位”。“无量纲井筒存储参数可以减少4到5个数量级。” 5.3.3 改进的Hantush方法假设，对于情况1和3（参见 图1 )，即封闭层远端源层中的水头保持不变。纽曼和威瑟斯彭 ( 7. ) 为一个案例开发了一个解决方案，该解决方案可能对应于Hantush的案例1 K " = O = S “但他们不要求未抽水含水层中的水头保持恒定。在这种情况下，他们得出结论，抽水含水层中的水位下降不会受到其他未抽水含水层特性的影响（Neuman和Witherspoon） ( 7. ) p、 810）时间满足: 5.3.4 假设中隐含的条件是，封闭层中的水流基本上是垂直的，含水层中的水流基本上是水平的。Hantush氏 ( 8. ) 对仅以一个渗漏封闭层为边界的含水层的分析表明，无论在何处，这些假设都是可以接受的精确性 含水层和约束层性质之间的这种关系形式也可能对两个渗漏约束层的情况提供有用的指导。

1.1 This practice covers an analytical procedure for determining the transmissivity and storage coefficient of a confined aquifer taking into consideration the change in storage of water in overlying or underlying confining beds, or both. This practice is used to analyze water-level or head data collected from one or more observation wells or piezometers during the pumping of water from a control well at a constant rate. With appropriate changes in sign, this practice also can be used to analyze the effects of injecting water into a control well at a constant rate. 1.2 This analytical procedure is used in conjunction with Test Method D4050 . 1.3 Limitations— The valid use of the modified Hantush method ( 1 ) 2 is limited to the determination of hydraulic properties for aquifers in hydrogeologic settings with reasonable correspondence to the assumptions of the Hantush-Jacob method (Practice D6029/D6029M ) with the exception that in this case the gain or loss of water in storage in the confining beds is taken into consideration (see 5.1 ). All possible combinations of impermeable beds and source beds (for example, beds in which the head remains uniform) are considered on the distal side of the leaky beds that confine the aquifer of interest (see Fig. 1 ). FIG. 1 Cross Sections Through Discharging Wells in Leaky Aquifers with Storage of Water in the Confining Beds, Illustrating Three Different Cases of Boundary Conditions (from Reed ( 2 ) ) 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . 1.4.1 The procedures used to specify how data are collected/recorded and calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of these test methods to consider significant digits used in analysis methods for engineering data. 1.5 The values stated in SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values for the two systems may result in nonconformance with the standard. Reporting of results in units other than SI shall not be regarded as nonconformance with this standard. 1.6 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of the practice may be applicable in all circumstances. This ASTM standard 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 document be applied without the 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. 1.7 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. 1.8 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 ====== 5.1 Assumptions: 5.1.1 The control well discharges at a constant rate, Q . 5.1.2 The control well is of infinitesimal diameter and fully penetrates the aquifer. 5.1.3 The aquifer is homogeneous, isotropic, and areally extensive. Note 1: Slug and pumping tests implicitly assume a porous medium. Fractured rock and carbonate settings may not provide meaningful data and information. 5.1.4 The aquifer remains saturated (that is, water level does not decline below the top of the aquifer). 5.1.5 The aquifer is overlain or underlain, or both, everywhere by confining beds individually having uniform hydraulic conductivities, specific storages, and thicknesses. The confining beds are bounded on the distal sides by one of the cases shown in Fig. 1 . 5.1.6 Flow in the aquifer is two-dimensional and radial in the horizontal plane. 5.2 The geometry of the well and aquifer system is shown in Fig. 1 . 5.3 Implications of Assumptions: 5.3.1 Paragraph 5.1.1 indicates that the discharge from the control well is at a constant rate. Paragraph 8.1 of Test Method D4050 discusses the variation from a strictly constant rate that is acceptable. A continuous trend in the change of the discharge rate could result in misinterpretation of the water-level change data unless taken into consideration. Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors. 5.3.2 The leaky confining bed problem considered by the modified Hantush method requires that the control well has an infinitesimal diameter and has no storage. Moench ( 6 ) generalized the field situation addressed by the modified Hantush ( 1 ) method to include the well bore storage in the pumped well. The mathematical approach that he used to obtain a solution for that more general problem results in a Laplace transform solution whose analytical inversion has not been developed and probably would be very complicated, if possible, to evaluate. Moench ( 6 ) used a numerical Laplace inversion algorithm to develop type curves for selected situations. The situations considered by Moench indicate that large well bore storage may mask effects of leakage derived from storage changes in the confining beds. The particular combinations of aquifer and confining bed properties and well radius that result in such masking is not explicitly given. However, Moench ( ( 6 ) , p. 1125) states “Thus observable effects of well bore storage are maximized, for a given well diameter, when aquifer transmissivity Kb and the storage coefficient S s b are small.” Moench (p. 1129) notes that “.one way to reduce or effectively eliminate the masking effect of well bore storage is to isolate the aquifer of interest with hydraulic packers and repeat the pump test under pressurized conditions. Because well bore storage C will then be due to fluid compressibility rather than changing water levels in the well”.“the dimensionless well bore storage parameter may be reduced by 4 to 5 orders of magnitude.” 5.3.3 The modified Hantush method assumes, for Cases 1 and 3 (see Fig. 1 ), that the heads in source layers on the distal side of confining beds remain constant. Neuman and Witherspoon ( 7 ) developed a solution for a case that could correspond to Hantush's Case 1 with K " = O = S " except that they do not require the head in the unpumped aquifer to remain constant. For that case, they concluded that the drawdowns in the pumped aquifer would not be affected by the properties of the other, unpumped, aquifer when (Neuman and Witherspoon ( 7 ) p. 810) time satisfies: 5.3.4 Implicit in the assumptions are the conditions that the flow in the confining beds is essentially vertical and in the aquifer is essentially horizontal. Hantush's ( 8 ) analysis of an aquifer bounded only by one leaky confining bed suggested that these assumptions are acceptably accurate wherever That form of relation between aquifer and confining bed properties may also be a useful guide for the case of two leaky confining beds.