ASTM D5716-95(2006)

Many mathematical equations for determining aquifer properties based on controlled field tests utilizing a single or multiple-pumping wells include a dependent variable, termed discharge, and generally designated as Q. Equations have been developed for constant and variable discharge. Those for variable discharge may specify regularly increasing, or regularly decreasing, or randomly varying discharge rate.

Aquifer testing has been conducted for the purposes of production and pressure relief well design and water resource assessment. Production wells are used for public and industrial water supplies, hydraulic controls, and groundwater capture. Pressure relief wells are for hydraulic controls. Test wells are for the purpose of water resource assessment.

Discharge must also be known for certain methods to evaluate well and pump performance.

FIG. 1 Construction of a Circular Orifice Weir⁵

1.1 This test method covers construction and operation of a circular orifice weir for measuring the discharge from a well. This test method is a part of a series of standards prepared on the in situ determination of hydraulic properties of aquifer systems by single- or multiple-well tests. Selection of a well discharge measurement test method is described in Guide D5737.

1.2 This test method is common to a number of aquifer test methods and to evaluation of well and pump performance.

1.3 Limitations—This test method is limited to the description of a method common to hydraulic engineering for the purpose of groundwater discharge measurement in temporary or test conditions.

1.4 Much of the information presented in this test method is based on work performed by the Civil Engineering Department of Purdue University during the late 1940s. The essentials of that work have been presented in a pamphlet prepared by Layne-Bowler, Inc. and updated by Layne Western Company, Inc.

1.5 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only.

1.6 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.