tag:blogger.com,1999:blog-55319852472047669422024-03-05T01:37:56.093-05:00AQTEBLOG (The AQTESOLV Blog)News and views on AQTESOLV, the world's <i>LEADING</i> software for the analysis of aquifer testshydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.comBlogger44125tag:blogger.com,1999:blog-5531985247204766942.post-58587976705845870172014-08-28T07:14:00.000-05:002014-08-28T07:14:27.270-05:00Interview With C.V. Theis<div class="separator" style="clear: both; text-align: center;">
<a href="http://timecapsule.iah.org/files/2012/08/theis_award-150x150.jpeg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://timecapsule.iah.org/files/2012/08/theis_award-150x150.jpeg" /></a></div>
Kick back and enjoy a lively and engaging <a href="http://timecapsule.iah.org/cv-theis-interview/">video</a> interview of Charles Vernon Theis who introduced the concept of transient flow to the interpretation of pumping tests. His seminal paper from 1935, "The relation between the lowering of the piezometric surface and the rate and duration of discharge of a well using groundwater storage," is familiar to all hydrogeologists. Learn more about his many accomplishments as well as the groundwater scientists with whom he worked during his long career at the U.S. Geological Survey.<br />
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Get more details on the <a href="http://www.aqtesolv.com/theis.htm">Theis solution</a> at the <a href="http://www.aqtesolv.com/">AQTESOLV website</a>.<br />
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Follow <b>AQTESOLV</b> on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv">LinkedIn</a> and <a class="vt-p" href="https://www.google.com/+aqtesolv">Google+</a> for more updates on aquifer testing!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-5974809959733786462014-05-13T05:02:00.003-05:002014-05-13T05:18:54.084-05:00Classic USGS Pumping Test VideoCheck out this classic video of a pumping test conducted by the U.S. Geological Survey in the Little Plover River basin in Wisconsin, USA.<br />
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<iframe allowfullscreen='allowfullscreen' webkitallowfullscreen='webkitallowfullscreen' mozallowfullscreen='mozallowfullscreen' width='320' height='266' src='https://www.youtube.com/embed/ZNJcVQBIE0Y?feature=player_embedded' frameborder='0'></iframe></div>
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The USGS study made news in a Milwaukee Sentinel <a class="vt-p" href="http://news.google.com/newspapers?nid=1368&dat=19611020&id=W3RQAAAAIBAJ&sjid=PhEEAAAAIBAJ&pg=4666,4544432">article</a> in 1961. A <a class="vt-p" href="http://fyi.uwex.edu/littleplovermodel/">new study</a> in this river basin is underway.<br />
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Follow <b>AQTESOLV</b> on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv">LinkedIn</a> and <a class="vt-p" href="https://www.google.com/+aqtesolv">Google+</a> for more news on aquifer testing!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-41276245622143960272014-05-03T12:01:00.001-05:002014-05-27T05:06:17.781-05:00Follow AQTESOLV on LinkedIn!Are you a member of the <b>LinkedIn</b> professional network?<br />
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If so, please visit the new <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv" target="_blank">AQTESOLV LinkedIn page</a> and click the <b>Follow</b> button to receive periodic LinkedIn updates pertaining to <a class="vt-p" href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm">aquifer testing</a> and <a class="vt-p" href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a>.<br />
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While you are visiting LinkedIn, follow the <a class="vt-p" href="https://www.linkedin.com/company/hydrosolve">HydroSOLVE company page</a> and feel free to send <a class="vt-p" href="https://www.linkedin.com/in/hydrosolve" target="_blank">me</a> an invitation to connect as well!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-26190071718031979222014-02-25T09:40:00.000-05:002014-05-03T11:50:57.262-05:00Show/Hide Well Data on PlotsWhen using <a class="vt-p" href="http://www.aqtesolv.com/">AQTESOLV</a> to perform <a class="vt-p" href="http://www.aqtesolv.com/visual_curve_matching.htm">visual curve matching</a> on a data set with multiple observation wells, it's often useful to turn off the display of one or more wells and focus your attention on the remaining wells.<br />
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To hide observation data for particular wells, choose <b>Edit>Wells</b> and select the wells in the list that you'd like to hide. Right click over the selection and choose <b>Hide Observations</b>.<br />
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<a class="vt-p" href="http://www.aqtesolv.com/images/Hide_Observations.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="http://www.aqtesolv.com/images/Hide_Observations.jpg" height="335" width="400" /></a></div>
To turn on the display of hidden observations wells, select the wells to display, right click over the selection and choose <b>Show Observations</b>.<br />
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Find more <a class="vt-p" href="http://www.aqtesolv.com/tips.htm">tips</a> on the <b>AQTESOLV</b> website!<br />
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Follow <b>AQTESOLV</b> on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv">LinkedIn</a> and <a class="vt-p" href="https://www.google.com/+aqtesolv">Google+</a>!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-26369429903733841472014-02-05T13:25:00.000-05:002014-05-03T11:51:55.718-05:00Checking Your Cooper and Jacob MatchGroundwater hydrologists use the <a class="vt-p" href="http://www.aqtesolv.com/cooper-jacob.htm">Cooper and Jacob (1946) solution</a> to determine the aquifer properties of a nonleaky confined aquifer using drawdowns measured during a constant-rate pumping test. The approximate method of Cooper and Jacob derives from the <a class="vt-p" href="http://www.aqtesolv.com/theis.htm">Theis (1935) type-curve method</a> when the variable u in the Theis well function, w(u), is sufficiently small (i.e., time is large or radius is small).<br />
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<a class="vt-p" href="http://www.aqtesolv.com/">AQTESOLV</a> has built-in tools to check the validity of analyses performed with the Cooper and Jacob method and to assist you with <a class="vt-p" href="http://www.aqtesolv.com/visual_curve_matching.htm">visual curve matching</a>. First, you can superimpose on your plot the time when u is less than a critical value. Choose <b>View>Options>Plots tab</b> and check the option for <b>Valid time for Cooper-Jacob approximation</b> (Figure 1).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/AQTESOLV_Cooper_Jacob_Valid_Time.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/AQTESOLV_Cooper_Jacob_Valid_Time.gif" height="320" width="319" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Check option to display valid time for Cooper and Jacob solution.</td></tr>
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Click the <b>Valid Time tab</b> to set the <b>critical value of u</b> (Figure 2). A critical value between 0.01 and 0.05 is typical.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/AQTESOLV_Cooper_Jacob_Valid_Time_Tab.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/AQTESOLV_Cooper_Jacob_Valid_Time_Tab.gif" height="320" width="319" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 2. Set critical value of u used to check validity of Cooper and Jacob approximation.</td></tr>
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When you activate the valid time option, a <b>dashed vertical line</b> appears on your time-drawdown or composite plot to indicate the time when the Cooper and Jacob approximation meets the critical value of u (Figure 3). The position of the vertical line is a function of T (transmissivity) and S (storage coefficient) as well as radial distance between the pumping and observation wells..<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/Cooper_Jacob_Valid_Time.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/Cooper_Jacob_Valid_Time.gif" height="256" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 3. Cooper and Jacob method (blue line) matched to time-drawdown data from constant-rate pumping test (data from Todd 1980). Dashed vertical line indicates time when Cooper and Jacob approximation becomes valid.</td></tr>
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The second way that you may evaluate the proper application of the Cooper and Jacob method using <b>AQTESOLV</b> is through <a class="vt-p" href="http://www.aqtesolv.com/derivative_analysis.htm">derivative analysis</a>. After superimposing the derivative on your semilog plot of drawdown versus time, match the Cooper and Jacob straight line to drawdowns corresponding to the <a class="vt-p" href="http://aqtesolv.blogspot.com/2014/01/iarf-and-cooper-and-jacob-method.html">derivative plateau</a>, i.e., during the period of <a class="vt-p" href="http://aqtesolv.blogspot.com/2014/01/infinite-acting-radial-flow-regime.html">infinite-acting radial flow</a> (Figure 4).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/Cooper_Jacob_Derivative_Plot.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/Cooper_Jacob_Derivative_Plot.gif" height="256" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 4. Cooper and Jacob method (blue line) matched to drawdown data during period of infinite-acting radial flow when derivative reaches plateau (red line).</td></tr>
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Use these two techniques to obtain more reliable results when using the <a class="vt-p" href="http://www.aqtesolv.com/cooper-jacob.htm">Cooper and Jacob method</a>. Get <a class="vt-p" href="http://www.aqtesolv.com/">AQTESOLV</a> and start applying these powerful tools in <i>your</i> next <a class="vt-p" href="http://www.aqtesolv.com/pumping_test_analysis.htm">pumping test interpretation</a>!<br />
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Visit the <a class="vt-p" href="http://www.aqtesolv.com/kb/default.htm">AQTESOLV Knowledge Base</a> to find more tips on the using the software. The <a class="vt-p" href="http://www.aqtesolv.com/support.htm#Manuals">AQTESOLV documentation</a> also includes a number of examples illustrating the use of the <a class="vt-p" href="http://www.aqtesolv.com/cooper-jacob.htm">Cooper and Jacob straight-line method</a>.<br />
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We invite you to follow HydroSOLVE on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv">LinkedIn</a> and <a class="vt-p" href="https://www.google.com/+aqtesolv">Google+</a>!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-53656075550127634222014-01-16T05:24:00.000-05:002014-05-03T11:52:28.377-05:00IARF and the Cooper and Jacob MethodGroundwater hydrologists routinely use the pumping test interpretation method of <a class="vt-p" href="http://www.aqtesolv.com/cooper-jacob.htm" target="_blank">Cooper and Jacob (1946)</a>, a straight-line approximation of the <a class="vt-p" href="http://www.aqtesolv.com/theis.htm" target="_blank">Theis (1935) type-curve solution</a>, to estimate the hydraulic properties of nonleaky confined aquifers from drawdown data measured during the period of <a class="vt-p" href="http://aqtesolv.blogspot.com/2014/01/infinite-acting-radial-flow-regime.html" target="_blank">infinite-acting radial flow (IARF)</a> when drawdown changes linearly with the logarithm of time. One expects to find IARF after the dissipation of early-time phenomena (e.g., wellbore storage) and prior to the advent of late-time effects such as aquifer boundaries.<br />
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Consider the well-known Theis solution for a constant-rate pumping test in a nonleaky confined aquifer of infinite extent:<br />
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<a align="center" class="vt-p" href="http://www.aqtesolv.com/images/Equation_Theis.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img align="center" border="0" src="http://www.aqtesolv.com/images/Equation_Theis.gif" /></a>..... (1)</div>
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<a class="vt-p" href="http://www.aqtesolv.com/images/Equation_u.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img align="center" border="0" src="http://www.aqtesolv.com/images/Equation_u.gif" /></a>..... (2)</div>
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<a class="vt-p" href="http://www.aqtesolv.com/images/Equation_Theis_compact.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img align="center" border="0" src="http://www.aqtesolv.com/images/Equation_Theis_compact.gif" /></a>..... (3)</div>
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<a class="vt-p" href="http://www.aqtesolv.com/images/Equation_w(u)_Infinite_Series.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img align="center" border="0" src="http://www.aqtesolv.com/images/Equation_w(u)_Infinite_Series.gif" /></a>..... (4)</div>
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where <i>s</i> is drawdown [L], <i>Q</i> is pumping rate [L<span style="font-family: Verdana;">³</span>/T],
<i>T</i> is transmissivity
[L<span style="font-family: Verdana;">²</span>/T], <i>t</i> is
time [T], <i>r</i> is radial distance [L] and <i>S</i> is storage
coefficient [-].<br />
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The Cooper and Jacob method approximates the Theis well function, <i>w(u)</i>, by truncating the infinite series in (4) after the first two terms:<br />
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<a class="vt-p" href="http://www.aqtesolv.com/images/Equation_w(u)_Cooper_Jacob.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img align="center" border="0" src="http://www.aqtesolv.com/images/Equation_w(u)_Cooper_Jacob.gif" /></a>..... (5)</div>
The approximation in (5) assumes that <i>u</i> is small, i.e., <i>t</i> is large and <i>r</i> is small. It is precisely when (5) is valid that infinite-acting radial flow is identified from drawdown data.<br />
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How small should <i>u</i> be for (5) to be valid? The threshold for IARF (i.e., when Cooper and Jacob becomes valid) is often given as u ≤ 0.05 (<a class="vt-p" href="http://www.aqtesolv.com/aquifer-tests/aquifer-testing-references.htm#Driscoll, F.G., 1986" target="_blank">Driscoll 1986</a>) or u ≤ 0.01 (<a class="vt-p" href="http://www.aqtesolv.com/aquifer-tests/aquifer-testing-references.htm#Kruseman, G.P. and N.A. de Ridder, 1994" target="_blank">Kruseman and de Ridder 1994</a>); however, we can see for ourselves when (5) is valid by plotting w(u) versus 1/u (dimensionless drawdown versus dimensionless time) on semilog axes and looking for a constant logarithmic derivative plateau (Figure 1).<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/Theis_Type_Curve_semilog.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/Theis_Type_Curve_semilog.gif" height="320" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Theis (1935) solution (blue curve) plotted as w(u) versus 1/u on semilog axes. Logarithmic derivative shown by red curve.</td></tr>
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It is evident from Figure 1 that the slope of the drawdown and the value of the derivative are each essentially constant when 1/u ≥ 50. Hence, when u ≤ 0.02, the Cooper and Jacob approximation of the Theis well function is safe to use. Figure 1 demonstrates just how useful <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">derivative analysis</a> can be for the detection of the IARF regime.<br />
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Visit <a class="vt-p" href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm" target="_blank">Aquifer Testing 101</a> to learn more about <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/constant-rate-pump-tests.htm" target="_blank">pumping test interpretation</a> with more examples of <b>infinite-acting radial flow</b>.<br />
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Follow <b>HydroSOLVE</b> on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv" target="_blank">LinkedIn</a> and <a class="vt-p" href="https://www.google.com/+aqtesolv">Google+</a>!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-80537447843906361082014-01-09T07:59:00.000-05:002014-05-03T11:54:08.201-05:00Infinite-Acting Radial Flow Regime<div class="separator" style="clear: both; text-align: center;">
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At the outset of interpreting a pumping test, an important feature to
detect in the response data is <b>infinite-acting radial flow</b>. During infinite-acting radial flow, steady pumping in a nonleaky
confined aquifer of infinite extent produces late-time drawdown that changes with the logarithm of
time since pumping began. Infinite-acting behavior occurs after wellbore storage effects have dissipated and before the influence of aquifer boundaries. One may observe this flow regime by plotting the familiar <a class="vt-p" href="http://www.aqtesolv.com/theis.htm" target="_blank">Theis (1935) solution</a> on semilog axes (Figure 1); at late time, a graph of dimensionless drawdown, w(u), versus dimensionless time, 1/u, plots as a straight
line and the <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">logarithmic derivative</a> is constant.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/Theis_Type_Curve_semilog.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/Theis_Type_Curve_semilog.gif" height="320" width="320" /></a> </td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Infinite-acting radial flow in a nonleaky confined aquifer illustrated with Theis (1935) solution (dimensionless drawdown and dimensionless derivative shown by blue and red curves, respectively).</td></tr>
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This late-time behavior of the Theis model is well known to groundwater hydrologists. The period of infinite-acting radial flow is the basis for the tried-and-true <a class="vt-p" href="http://www.aqtesolv.com/cooper-jacob.htm" target="_blank">Cooper and Jacob (1946) method</a> which
one may use to find the transmissivity and storage coefficient of a nonleaky confined aquifer by matching a straight line to late-time drawdown data from a constant-rate pumping test plotted on semilog axes.<br />
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A <a class="vt-p" href="http://aqtesolv.blogspot.com/2012/07/catalog-of-derivative-plots.html" target="_blank">derivative plot</a> is very useful for detecting the infinite-acting radial flow regime under steady pumping conditions. One starts by looking for a <b>derivative plateau</b> (constant derivative) to tentatively identify infinite-acting radial flow. For example, the response data from a constant-rate pumping test shown in Figure 2 suggest that infinite-acting radial flow conditions are present after approximately 30 minutes of pumping once the derivative stabilizes.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a class="vt-p" href="http://www.aqtesolv.com/images/derivative-gridley.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="http://www.aqtesolv.com/images/derivative-gridley.gif" height="295" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 2. Derivative plot of drawdown (squares) and derivative (crosses) measured in an observation well during constant-rate pumping test in a nonleaky confined aquifer (Walton 1962).</td></tr>
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Note that the derivative plateau in Figure 2 exhibits some noise; derivative fluctuation at the plateau is common in the <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">application of derivative analysis</a>, but the presence of a near-constant derivative in this example is clear and corresponds to the emergence of a well-defined straight line in the drawdown data.<br />
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The foregoing results suggest that the derivative plot is an indispensable tool for aquifer test interpretation; however, the mere existence of a derivative plateau does not immediately confirm infinite-acting radial flow conditions. For example, an <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/pumping-tests-in-bounded-aquifers.htm#No-Flow-Boundary" target="_blank">aquifer limited by a no-flow boundary</a> can produce a constant derivative that is not diagnostic of the infinite-acting radial flow regime. In such a situation, geologic mapping of lithologic contacts, faults and other low-permeability features would be invaluable in making a correct interpretation.<br />
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Visit <a class="vt-p" href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm" target="_blank">Aquifer Testing 101</a> for a <a class="vt-p" href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Catalog of Derivative Plots" target="_blank">catalog of derivative plot signatures</a> with more examples of <b>infinite-acting radial flow</b> in pumping tests.<br />
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Follow <b>HydroSOLVE</b> on <a class="vt-p" href="https://www.linkedin.com/company/aqtesolv" target="_blank">LinkedIn</a>!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-32025579785124197792013-12-10T11:14:00.000-05:002013-12-10T11:16:42.495-05:00Curve Matching With Multiple Observation WellsWhen you <a href="http://aqtesolv.blogspot.com/2013/12/analyzing-pumping-tests-with-multiple.html" target="_blank">analyze a pumping test with more than one observation well</a>, <b>AQTESOLV</b> matches <b><i>one</i></b> set of aquifer properties to the drawdown data from <b><i>all</i></b> of the wells in your data set.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/composite_plot_Gironde_France.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="247" src="http://www.aqtesolv.com/images/composite_plot_Gironde_France.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">One set of aquifer properties matched to two observation wells from a constant-rate pumping test in an unconfined aquifer with delayed yield.</td></tr>
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In the figure shown above, the curve-fitting analysis determines the properties of an unconfined aquifer with delayed yield from the two observation wells displayed on the graph.<br />
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Of course, if your data set has multiple observation wells, you may match wells individually or in groups with <b>AQTESOLV</b> as well. To perform <a href="http://www.aqtesolv.com/visual_curve_matching.htm" target="_blank">visual curve matching</a> on selected wells, choose <b>Wells</b> from the <b>Edit</b> menu to see all of the wells in your data set. Right click over a well in the list and choose <b>Hide Observations</b> to turn off the display of the well; to turn on the display a previously hidden well, choose <b>Show Observations</b> when you right click over a well.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/AQTESOLV_Well_List.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="300" src="http://www.aqtesolv.com/images/AQTESOLV_Well_List.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Choose Edit>Wells to add, modify or delete wells from an AQTESOLV data set.</td></tr>
</tbody></table>
To select more than one well at a time, hold down the <b>Ctrl</b> key when clicking on wells in the list shown above.<br />
<br />
<b>AQTESOLV</b> allows you to select which wells to use for <a href="http://www.aqtesolv.com/automatic_curve_matching.htm" target="_blank">automatic curve matching</a>, too. Choose <b>Automatic</b> from the <b>Match</b> menu and click the <b>Active Wells</b> tab. Remove the check next to any well that you wish to ignore during automatic matching.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/automatic_curve_matching_select_wells.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="340" src="http://www.aqtesolv.com/images/automatic_curve_matching_select_wells.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Choose Match>Automatic>Active Wells to select wells to match with automatic curve matching.</td></tr>
</tbody></table>
Selections in the <b>Active Wells</b> list shown above only affect the wells used for automatic matching, not the display of well data.<br />
<br />
Visit the <a href="http://www.aqtesolv.com/support.htm" target="_blank">Support Center</a> and the <a href="http://www.aqtesolv.com/kb/default.htm" target="_blank">Knowledge Base</a> at the <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV website</a> for additional tips and examples.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-34065715185833819202013-12-04T09:03:00.000-05:002013-12-08T07:26:33.789-05:00Analyzing Pumping Tests With Multiple Observation Wells<b>AQTESOLV</b> allows you to analyze pumping tests with more than one observation well. For example, Figure 1 shows the interpretation of drawdown data recorded in the pumped well and three observations wells during a <a href="http://www.aqtesolv.com/pumping-tests/constant-rate-pump-tests.htm" target="_blank">constant-rate pumping test</a> conducted in a nonleaky confined channel aquifer (near Estevan, Saskatchewan, Canada).<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Estevan-channel-aquifer.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="238" src="http://www.aqtesolv.com/images/Estevan-channel-aquifer.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Constant-rate pumping test in nonleaky confined channel aquifer (Walton 1970).</td></tr>
</tbody></table>
Prior to late-time <a href="http://www.aqtesolv.com/pumping-tests/pumping-tests-in-bounded-aquifers.htm" target="_blank">boundary effects</a>, one observes infinite-acting aquifer conditions in the drawdown response at all wells (Figure 1).<br />
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Analysis of multiple observation wells is not limited to nonleaky confined aquifers. In the following figure, we see the analysis of drawdown data from a constant-rate pumping test in a leaky confined aquifer with three observation wells.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/usbr-texas-hill-hantush-jacob-composite.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="246" src="http://www.aqtesolv.com/images/usbr-texas-hill-hantush-jacob-composite.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 2. Constant-rate pumping test in leaky confined aquifer (USBR 1995).</td></tr>
</tbody></table>
Interpretation of this test uses the <a href="http://www.aqtesolv.com/hantush-jacob.htm" target="_blank">Hantush and Jacob (1955) method</a> for a leaky confined aquifer with incompressible aquitard(s). Prior to the onset of leakage, the aquifer behaves like a nonleaky confined aquifer of infinite extent as shown in Figure 2 by the superimposed <a href="http://www.aqtesolv.com/theis.htm" target="_blank">Theis (1935) solution</a> (red curve).<br />
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We can use <b>AQTESOLV</b> to analyze multi-well tests in phreatic aquifers, too. For example, two fully penetrating observation wells are used for the interpretation of a constant-rate pumping test in an unconfined aquifer with delayed yield near Gironde, France (Figure 3).<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/composite_plot_Gironde_France.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="247" src="http://www.aqtesolv.com/images/composite_plot_Gironde_France.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 3. Constant-rate pumping test in unconfined aquifer with delayed yield (Neuman 1975).</td></tr>
</tbody></table>
Analysis in the example above is performed with the <a href="http://www.aqtesolv.com/neuman.htm" target="_blank">Neuman (1974) method</a> for an anisotropic water-table aquifer with delayed gravity response; one can see from the composite plot how the shape of the drawdown response is affected by radial distance from the pumping well (Figure 3).<br />
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Figure 4 shows the interpretation of a multi-well constant-rate pumping test in a double-porosity fractured aquifer using a solution by <a href="http://www.aqtesolv.com/moenchf.htm" target="_blank">Moench (1984)</a>.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Moench_1984_benchmark_NTS.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="258" src="http://www.aqtesolv.com/images/Moench_1984_benchmark_NTS.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 4. Constant-rate pumping test in double-porosity fractured aquifer (Moench 1984).</td></tr>
</tbody></table>
In the example above, the blue curve on the composite plot shows the fit to drawdown data from the pumped well while the red curve is matched to observation well data.<br />
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In each of the preceding examples, <b><i>one</i></b> set of aquifer properties was used to match drawdown data from <b><i>all</i></b> observation wells in a data set. At times, however, you may wish to match only a few wells by themselves. You may accomplish this task using either <a href="http://www.aqtesolv.com/visual_curve_matching.htm" target="_blank">visual</a> or <a href="http://www.aqtesolv.com/automatic_curve_matching.htm" target="_blank">automatic curve matching</a> in <b>AQTESOLV</b>.<br />
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Sometimes you start out with only one or two observation wells in a data set and wish to add more wells later. Adding observation wells is easy with <b>AQTESOLV</b>. Choose <b>Wells</b> from the <b>Edit</b> menu and click <b>New</b> to enter data for a new well.<br />
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To find worked examples of pumping tests with multiple observation wells, check out the <a href="http://www.aqtesolv.com/support.htm" target="_blank">AQTESOLV Help file/manual</a> or visit the <a href="http://www.aqtesolv.com/gallery.htm" target="_blank">Application Gallery</a> at the <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV web site</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-16418039632142060122013-11-26T11:47:00.000-05:002013-11-27T06:34:58.166-05:00Entering Pumping Rates Into AQTESOLVEntering pumping rates from an aquifer test into <b>AQTESOLV</b> requires little effort. The first thing to remember is that all pumping rates are entered as a sequence of constant-rate steps. For each step, enter the time when the step begins (as elapsed time since the start of the test) with the corresponding pumping rate. For your convenience, <b>AQTESOLV</b> provides options to type the rates into a spreadsheet, import them from a file or copy/paste them from another spreadsheet.<br />
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<b><i><u>Constant-Rate Test</u></i></b><br />
<div>
For a constant-rate pumping test, you only need to enter <i>one rate</i> into <b>AQTESOLV</b>. For example, if the pumping rate during a constant-rate test is 100 gpm (gallons-per-minute), enter the rate as shown below.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Rates_Spreadsheet_Constant_Rate_Test.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="276" src="http://www.aqtesolv.com/images/Rates_Spreadsheet_Constant_Rate_Test.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Pumping rate entry for a constant-rate test.</td></tr>
</tbody></table>
<div>
Note that there's no need to duplicate the rate in the spreadsheet after the first entry. <b>AQTESOLV</b> assumes that the rate doesn't change until you add a new one. Duplicating rates in successive rows of the spreadsheet only serves to slow down calculations.</div>
<div>
The following figure shows an interpretation of drawdown data from a constant-rate pumping test with the <a href="http://www.aqtesolv.com/theis.htm" target="_blank">Theis (1935) type-curve method</a>.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Theis-Gridley-pumping-test.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="237" src="http://www.aqtesolv.com/images/Theis-Gridley-pumping-test.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Analysis of drawdown data from constant-rate pumping test.</td></tr>
</tbody></table>
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<b><i><u>Constant-Rate Test With Recovery</u></i></b><br />
<div>
Now consider a constant-rate pumping test with recovery. For this case, enter the constant-rate portion of the test as above and add a row to the rates spreadsheet to indicate the start of recovery. For example, if pumping at 100 gpm ceases after 24 hours (1440 minutes), enter the constant rate and recovery periods as follows.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Rates_Spreadsheet_Constant_Rate_Test_With_Recovery.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="276" src="http://www.aqtesolv.com/images/Rates_Spreadsheet_Constant_Rate_Test_With_Recovery.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Pumping rate entry for a constant-rate test with recovery.</td></tr>
</tbody></table>
<div>
The next graph shows the rate history for the example above. The rate during the pumping test is a constant 100 gpm. After one day (1440 minutes), the test ends and the rate is zero during recovery.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Rate_History_Constant_Rate_Test_With_Recovery.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="355" src="http://www.aqtesolv.com/images/Rate_History_Constant_Rate_Test_With_Recovery.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Rate history for constant-rate test with recovery.</td></tr>
</tbody></table>
<div>
As before, do not duplicate pumping rates in successive rows of the rates spreadsheet. Between 0 and 1440 minutes, <b>AQTESOLV</b> recognizes that the constant rate is 100 gpm. <b>AQTESOLV</b> knows from the data entered that the rate after 1440 minutes is zero during recovery.</div>
<div>
The plot below illustrates the analysis of drawdown and recovery data from a constant-rate pumping test with recovery.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/usbr-combined-analysis-theis.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="243" src="http://www.aqtesolv.com/images/usbr-combined-analysis-theis.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Analysis of constant-rate pumping test with recovery.</td></tr>
</tbody></table>
<br />
<b><i><u>Variable-Rate Test</u></i></b><br />
<div>
Entering pumping rates for a variable-rate test is likewise straightforward. Enter a new rate into <b>AQTESOLV</b> <i>when the rate changes</i>. For example, consider a step-drawdown test consisting of three one-hour steps of 50, 100 and 150 gpm. As before, the first step starts at an elapsed time of zero. The second and third steps begin at 60 and 120 minutes, respectively.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Rates_Spreadsheet_Step_Test.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="276" src="http://www.aqtesolv.com/images/Rates_Spreadsheet_Step_Test.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Pumping rate entry for step-drawdown test.</td></tr>
</tbody></table>
<div>
The rate history for this step-drawdown test example is illustrated in the graph below.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Rate_History_Step_Drawdown_Test.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="368" src="http://www.aqtesolv.com/images/Rate_History_Step_Drawdown_Test.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Rate history for step-drawdown test.</td></tr>
</tbody></table>
<div>
Enter only one row per step in the rates spreadsheet to indicate when the step begins. During each step, the pumping rate is assumed to remain constant.</div>
<div>
Interpretation of a step-drawdown test with recovery is shown in the following figure.</div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/step-drawdown-test-theis-clark.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="240" src="http://www.aqtesolv.com/images/step-drawdown-test-theis-clark.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Interpretation of drawdown and recovery data from a step-drawdown test.</td></tr>
</tbody></table>
<div>
Visit the <a href="http://www.aqtesolv.com/kb/default.htm" target="_blank">Knowledge Base</a> at the <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV website</a> for more helpful tips on using the software!</div>
hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-90835498622227721412013-11-19T11:38:00.000-05:002013-11-19T11:43:55.666-05:00AQTESOLV Examples and TutorialsThe <b>Help file</b> installed with <b>AQTESOLV</b> is chock-full of examples with step-by-step instructions for using the software.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/AQTESOLV_Help_System.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="325" src="http://www.aqtesolv.com/images/AQTESOLV_Help_System.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Accessing Examples in the AQTESOLV Help System</td></tr>
</tbody></table>
To access the Help system, choose <b>Contents and Index</b> from the <b>Help</b> menu in the <b>AQTESOLV</b> application. Go to the <b>Quick Start</b> chapter in the <b>Contents</b> tab to explore the many detailed tutorials for analyzing pumping tests, slug tests and constant-head tests.<br />
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To download a <b>PDF</b> version of the <b>AQTESOLV</b> manual, please visit the <a href="http://www.aqtesolv.com/support.htm" target="_blank">Support Center</a> at the <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV website</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-46556148526723672282013-11-13T08:32:00.000-05:002013-11-13T17:51:13.116-05:00Intermittent PumpingOne of the many applications for the <a href="http://www.aqtesolv.com/pumping_test_analysis.htm#Variable_Rates" target="_blank">variable pumping rate</a> option in <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a> is to simulate drawdown resulting from <b>intermittent pumping</b> in one or more pumping wells. Use this feature for <a href="http://www.aqtesolv.com/pumping_test_analysis.htm" target="_blank">pumping test interpretation</a> or <a href="http://www.aqtesolv.com/prediction_and_test_design.htm" target="_blank">drawdown modeling</a>.<br />
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In the following figure, <b>AQTESOLV</b> predicts drawdown due to an irrigation well extracting water from a nonleaky confined aquifer with daily on/off cycles extending over a growing season of 245 days. During each pumping cycle, the well withdraws groundwater at 220 gallons-per-minute (gpm) for 12 hours followed by 12 hours of recovery. At the end of the growing season, all pumping stops and sustained recovery begins. Drawdown in the pumping well (<span style="color: blue;">blue line</span>) clearly shows the cycles of intermittent pumping; whereas the two observation wells (<span style="color: red;">red lines</span>) located 500 and 2000 ft from the extraction well demonstrate how the cyclic drawdown response dissipates with distance.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Intermittent_Pumping_Theis.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="256" src="http://www.aqtesolv.com/images/Intermittent_Pumping_Theis.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Drawdown due to intermittent (cyclic) pumping in a nonleaky confined aquifer.</td></tr>
</tbody></table>
<div class="separator" style="clear: both; text-align: center;">
</div>
Entering a lot of pumping cycles by hand can be tedious, so <b>AQTESOLV</b> makes the task easy for you. One method is to prepare the cyclic rate history in Excel and copy/paste the rates from Excel into <b>AQTESOLV</b>. Alternatively, you may enter just one cycle into <b>AQTESOLV</b> and have the software repeat the cycle a specified number of times (find details in the <a href="http://www.aqtesolv.com/support.htm#Manuals" target="_blank">AQTESOLV manual</a>).<br />
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If your primary interest is the average drawdown at relatively distant observation wells over long periods of intermittent pumping, it is often sufficient to assume a constant average pumping rate. The following figure shows the predicted drawdown for a well extracting at 110 gpm over the same 245-day growing season as the previous intermittent pumping scenario.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.aqtesolv.com/images/Intermittent_Pumping_Theis_Average_Rate.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="256" src="http://www.aqtesolv.com/images/Intermittent_Pumping_Theis_Average_Rate.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Drawdown assuming average pumping rate in a nonleaky confined aquifer.</td></tr>
</tbody></table>
The two preceding examples applied the <a href="http://www.aqtesolv.com/theis.htm" target="_blank">Theis (1935) nonequilibrium solution</a> to predict drawdown under intermittent pumping conditions in a nonleaky confined aquifer of infinite extent; however, you may use virtually <i>any</i> of the <a href="http://www.aqtesolv.com/summary_of_solutions.htm" target="_blank">pumping test solutions in AQTESOLV</a> to forecast drawdown for constant- or variable-rate pumping in nonleaky confined, leaky confined, unconfined or fractured aquifers. Plus, <b>AQTESOLV</b> allows you to add <a href="http://www.aqtesolv.com/bounded_aquifers.htm" target="_blank">no-flow or constant-head boundaries</a> to model surface water boundaries and limited aquifers as required.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-82652961170283057052013-11-06T06:45:00.000-05:002013-11-07T06:16:14.811-05:00Distance-Drawdown Analysis<a href="http://www.aqtesolv.com/pumping_test_analysis.htm#Interference_Tests" target="_blank">Distance-drawdown analysis</a> is a useful technique for estimating aquifer properties when drawdown measurements are taken during a pumping test at several observation wells located at different radial distances from the control (pumped) well. To perform distance-drawdown analysis, one plots a single drawdown observation per well, each recorded at the same time since the start of pumping, on a <b>graph of drawdown versus radial distance</b>.<br />
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Most of us are familiar with estimating an aquifer's <a href="http://www.aqtesolv.com/aquifer-tests/glossary-of-aquifer-testing-terms.htm#Transmissivity" target="_blank">transmissivity</a> and <a href="http://www.aqtesolv.com/aquifer-tests/glossary-of-aquifer-testing-terms.htm#Storativity" target="_blank">storativity</a> from distance-drawdown data using the <a href="http://www.aqtesolv.com/cooper-jacob.htm">Cooper and Jacob (1946) method</a> as shown in the following figure.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><img alt="Distance-drawdown analysis, Cooper and Jacob (1956)" border="0" height="256" src="http://www.aqtesolv.com/images/usbr-sioux-flats-unconfined-cooper-jacob-distance-drawdown.gif" style="display: block; margin-left: auto; margin-right: auto;" width="400" /></td></tr>
<tr><td class="tr-caption">Distance-drawdown analysis for an unconfined aquifer.</td></tr>
</tbody></table>
<div>
Did you know that you may perform distance-drawdown analysis with <a href="http://www.aqtesolv.com/summary_of_solutions.htm">pumping test methods in AQTESOLV</a> other than Cooper and Jacob? For example, you may match distance-drawdown data with the <a href="http://www.aqtesolv.com/hantush-jacob.htm">Hantush and Jacob (1955) method for a leaky confined aquifer</a> (see figure below).<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><img border="0" height="247" src="http://www.aqtesolv.com/images/distance_drawdown_texas_hill.gif" style="display: block; margin-left: auto; margin-right: auto;" width="400" /></td></tr>
<tr><td class="tr-caption">Distance-drawdown plot for a leaky confined aquifer.</td></tr>
</tbody></table>
To display a distance-drawdown graph in <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a>, choose <b>Distance-Drawdown</b> from the <b>View</b> menu. The <b>Distance-Drawdown</b> option is active when you have more than one observation well in your data set. If your data set includes more than one pumping well, the <b>Distance-Drawdown</b> option is inactive as distance-drawdown analysis assumes radially symmetric flow around a single pumping well; however, you may use <b>AQTESOLV</b> to prepare <a href="http://www.aqtesolv.com/contouring.htm" target="_blank">contour plots of drawdown</a> (plan and cross section) when multiple pumping wells are present.<br />
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To learn more about <b>AQTESOLV</b>, take the <a href="http://www.aqtesolv.com/tour.htm" target="_blank">guided tour</a> or <a href="http://www.aqtesolv.com/demo.htm" target="_blank">download the demo</a>!</div>
hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-14259941344151205752013-10-23T07:59:00.000-05:002013-10-24T07:35:29.487-05:00Plot Orientation in AQTESOLVMany groundwater hydrologists prefer plotting drawdown data from a pumping test with the origin placed in the upper left corner of the graph. When formatted this way, a graph shows drawdown increasing downward.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGNkZslKL0X39aTs_F9OP8ip6FSzn7KR2fCM8AUFxhSajwiX_1qLa9aUJkQmoMoJHPN_Y9hLa8tm7uXYiQlLoKZQc35AhF0MxYOIrNVjWEc5gWoykzsA9pLlnAhtjxaDePKMjDQw17qB1b/s1600/USBR_Recovery.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="252" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGNkZslKL0X39aTs_F9OP8ip6FSzn7KR2fCM8AUFxhSajwiX_1qLa9aUJkQmoMoJHPN_Y9hLa8tm7uXYiQlLoKZQc35AhF0MxYOIrNVjWEc5gWoykzsA9pLlnAhtjxaDePKMjDQw17qB1b/s400/USBR_Recovery.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Analysis of drawdown and recovery from a pumping test in a confined aquifer.</td></tr>
</tbody></table>
To have <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a> orient your drawdown plot in this manner, choose <b>Format</b> from the <b>View</b> menu and check <b>Origin in Upper Left</b>.<br />
<br />
For additional <b>AQTESOLV</b> tips, visit the <a href="http://www.aqtesolv.com/kb/default.htm" target="_blank">Knowledge Base</a> and <a href="http://www.aqtesolv.com/examples/default.htm" target="_blank">Examples</a> at the <a href="http://www.aqtesolv.com/support.htm" target="_blank">AQTESOLV Support Center</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-36064616339728794512013-09-02T12:55:00.000-05:002013-09-02T17:54:17.657-05:00Follow Us On LinkedIn!Are you a member of the <b>LinkedIn</b> professional network?<br />
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If so, please visit our <a href="https://www.linkedin.com/company/hydrosolve" target="_blank">company page</a> and click the <b>Follow</b> button to receive periodic updates pertaining to aquifer testing and <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a>.<br />
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Or just click the button below to follow us:.<br />
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While you are visiting LinkedIn, feel free to send <a href="https://www.linkedin.com/in/hydrosolve" target="_blank">me</a> an invitation to connect as well!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-49385091802489835232012-11-14T04:17:00.000-05:002013-11-07T06:34:14.445-05:00AQTESOLV Voted #1 Software In Poll<b><i>What is the best pumping test analysis software?</i></b> Groundwater professionals, responding to a <a href="http://linkd.in/Q36zdK" target="_blank">recent poll on LinkedIn</a>, <i>overwhelmingly</i> chose <a href="http://www.aqtesolv.com/">AQTESOLV</a> as their <a href="http://www.aqtesolv.com/pumping_test_analysis.htm#Best_pumping_test_analysis_software" target="_blank">preferred software for pumping test analysis</a>.[<a href="http://www.aqtesolv.com/Poll_Results_LinkedIn_3.pdf" target="_blank">pdf</a>]<br />
<div class="separator" style="clear: both; text-align: center;">
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5KYHX6-fyJ0jfmZcq_2szMOvcH53gk-iXND_tgeRS12LR_SPig10L3PCJ6-Y5s6a-jWDYuUcZWHYdp4wDnof67qliA7NCh372VA8NlNf32hCR4oQhn3KA62N_CShPU4QkqbvJJfbGUE8w/s1600/LinkedIn_Pumping_Test_Software_Poll_Final_Results.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="207" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5KYHX6-fyJ0jfmZcq_2szMOvcH53gk-iXND_tgeRS12LR_SPig10L3PCJ6-Y5s6a-jWDYuUcZWHYdp4wDnof67qliA7NCh372VA8NlNf32hCR4oQhn3KA62N_CShPU4QkqbvJJfbGUE8w/s400/LinkedIn_Pumping_Test_Software_Poll_Final_Results.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Results of LinkedIn poll, "What's your preferred pumping test software?"</td></tr>
</tbody></table>
Here's just a sample of <a href="http://linkd.in/Q36zdK" target="_blank">comments</a> posted by participants in the pumping test software poll:<br />
<ul>
<li><span style="background-color: #fff2cc; font-family: inherit;">"AQTESOLV [has] a great solution set with real flexibility."</span></li>
<li><span style="font-family: inherit;">"AQTESOLV is not only a great solution but is user friendly and has great customer support that comes along with it."</span></li>
<li><span style="background-color: #fff2cc; font-family: inherit;">"AQTESOLV is the industry's standard. Glenn D[uffield] does a great job with continuing updating and improving an already superb product."</span></li>
<li><span style="font-family: inherit;">"AQTESOLV is a fantastic tool. Easy to use, informative help documentation, and great customer support."</span></li>
<li><span style="background-color: #fff2cc; font-family: inherit;">"Totally agree with the other commenters [regarding AQTESOLV]. Glenn [Duffield] has built a wonderful product that is both powerful and user-friendly. Oh, and speaking of friendly, if a person has a question about the software, Glenn is very quick to provide help, either by phone or email. Great product, great customer service. What more could you want?"</span></li>
</ul>
Thanks to everyone who voted in the poll and for all of the kind words!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-58737311188730567602012-07-09T08:12:00.001-05:002012-07-09T08:13:46.378-05:00Catalog of Derivative Plots<a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">Derivative analysis</a> is a powerful diagnostic technique for the interpretation of data from <a href="http://www.aqtesolv.com/pumping-tests/pump-tests.htm" target="_blank">pumping tests</a>. Use of the derivative in pumping test analysis can highlight many flow regime features that otherwise may be hard to discover when inspecting drawdown data alone.<br />
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A <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Catalog%20of%20Derivative%20Plots" target="_blank">catalog of derivative plots</a>, showing the theoretical drawdown and derivative signatures on log-log axes for different flow regimes, is a useful reference to the practicing hydrogeologist when performing derivative analysis. For example, Figure 1 shows the drawdown and derivative response for a finite-diameter pumping well with wellbore storage in an infinite nonleaky confined aquifer.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgDGvxEqDPrHeSijQB5znT5a642ZO4lcGxt3ISOV55mbHR4Q5YO1jwyQ4pmqTKE41x3WuwFVlQi-KwOMFnCB7i_qtd2xrnAMEyFKU3q-5GJbJwR8lun51h9rD3-IaMA20YrZU5_5CoDA7EI/s1600/derivative_plot_confined_papadopulos_cooper_pw.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgDGvxEqDPrHeSijQB5znT5a642ZO4lcGxt3ISOV55mbHR4Q5YO1jwyQ4pmqTKE41x3WuwFVlQi-KwOMFnCB7i_qtd2xrnAMEyFKU3q-5GJbJwR8lun51h9rD3-IaMA20YrZU5_5CoDA7EI/s400/derivative_plot_confined_papadopulos_cooper_pw.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Wellbore storage flow regime, infinite nonleaky confined aquifer.</td></tr>
</tbody></table>
One observes the wellbore storage flow regime at early time when the drawdown and derivative curves both exhibit unit (1:1) slopes (Figure 1). Radial flow in an infinite-acting aquifer shows up as a plateau on the derivative response.<br />
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An extensive <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Catalog%20of%20Derivative%20Plots" target="_blank">catalog of derivative plots</a> is available at the <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm" target="_blank">Aquifer Testing 101</a> section of the <a href="http://www.aqtesolv.com/" target="_blank">AQTESOLV</a> web site to help you with derivative analysis. Use the catalog to become familiar with the derivative plot signatures for various well/aquifer geometries corresponding to different flow regimes.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-62394662790879780732012-06-24T18:47:00.000-05:002012-06-25T09:56:58.666-05:00Importance of Smoothing Derivative Data<b>Derivative analysis</b> is a powerful diagnostic tool that enhances the interpretation of pumping test data. Hydrogeologists use the technique to identify flow regimes, discern boundary conditions and refine the selection of aquifer models.<br />
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Derivatives are not measured directly in the field; rather, they are <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Derivative%20Calculation" target="_blank">computed by numerical differentiation</a> from drawdowns collected during a pumping test. Straightforward calculation of the derivative from neighboring drawdown measurements typically leads to noisy derivative data. Therefore, <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Derivative%20Calculation" target="_blank">smoothing routines</a> are employed to obtain a cleaner derivative signal (Bourdet et al. 1989; Spane and Wurstner 1993).<br />
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To appreciate the importance of derivative smoothing, consider field data measured in a deep piezometer during a
constant-rate pumping test performed in an unconfined aquifer (Kruseman
and de Ridder 1994). Figure 1 is a derivative plot for the piezometer showing drawdown (squares) and
derivatives (crosses) computed without smoothing (nearest neighbor
method). Without smoothing, the derivative data provide little useful information for the interpretation of this test.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBx8aKpxa_0NEcRRHiJ9PxpwcO5f0ZjYT6BAHaskGLqVCoXJX1gaB6qftjvRRFgxpgW_QndLoIOKeIObTrDf96K7fLjDzk-x5LTvTyOLrGGc0cWb8YuueKwVUNf34-tJFHPpD-I0KbTGDF/s1600/derivative_nearest_neighbor_vennebulten.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="302" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBx8aKpxa_0NEcRRHiJ9PxpwcO5f0ZjYT6BAHaskGLqVCoXJX1gaB6qftjvRRFgxpgW_QndLoIOKeIObTrDf96K7fLjDzk-x5LTvTyOLrGGc0cWb8YuueKwVUNf34-tJFHPpD-I0KbTGDF/s320/derivative_nearest_neighbor_vennebulten.gif" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 1. Derivative plot showing derivatives computed without smoothing.</td></tr>
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<div style="text-align: left;">
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Application of the <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Derivative%20Calculation" target="_blank">Bourdet method</a> to smooth the derivatives leads to a derivative plot with useful information (Figure 2). The trough in the derivative curve shown in Figure 2 is typical for an <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm#Instantaneous%20Drainage%20at%20Water%20Table" target="_blank">unconfined aquifer with delayed yield</a>. The derivative signature suggests the possibility of using a mathematical model by Neuman (1974) to interpret the data.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYfIHGTk-z9J-tFEU7KdAYcRSh-id3meuRvaatjojuO6oaHXKIT4CWjpJweDZRBDvINWGdfb-XUf9b1Fc_w2janUu1Ac5P9S972inbhkylDmy8YzjB-YClW304Sulgm8r8HgwFwP4EPAj_/s1600/derivative_smoothing_bourdet_vennebulten.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="302" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiYfIHGTk-z9J-tFEU7KdAYcRSh-id3meuRvaatjojuO6oaHXKIT4CWjpJweDZRBDvINWGdfb-XUf9b1Fc_w2janUu1Ac5P9S972inbhkylDmy8YzjB-YClW304Sulgm8r8HgwFwP4EPAj_/s320/derivative_smoothing_bourdet_vennebulten.gif" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Figure 2. Derivative plot showing derivatives computed with Bourdet smoothing.</td></tr>
</tbody></table>
<b>AQTESOLV</b> features <a href="http://www.aqtesolv.com/derivative_analysis.htm" target="_blank">three smoothing methods</a> for computing derivatives including the Bourdet and Spane methods.<br />
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More information on <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">derivative analysis</a> is available at <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm" target="_blank">Aquifer Testing 101</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-15160548892476857132012-06-19T06:02:00.000-05:002012-06-24T17:29:27.516-05:00Hydraulics of Wells<i><b>Hydraulics of Wells</b></i> by M. S. Hantush (1964) is available for <a href="https://www.ees.nmt.edu/deceased/213-hantush-wellshydrolics" target="_blank">download</a>. This classic work is a recommended reference for the bookshelf of every practicing hydrogeologist.<br />
<br />
To find more aquifer testing materials including other links to downloadable resources, check out my <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-testing-references.htm" target="_blank">reference list</a> at the <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm" target="_blank">Aquifer Testing 101</a> web site.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-9766095592039859732012-03-21T15:50:00.003-05:002012-03-21T15:59:51.055-05:00Three-Day Aquifer Testing Course in BaltimoreI'm very excited about the upcoming aquifer testing course entitled <i><b>Advanced Aquifer Testing Techniques Featuring AQTESOLV: New Concepts, Field Methods and Data Analysis Procedures</b></i> to be held in Baltimore, Maryland, USA on April 24-26, 2012. It's the first time that we've offered the three-day course in the USA since 2009.<br />
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The instructors at this year's course will include <b>Dr. Jim Butler</b> of the Kansas Geological Survey, <b>Dr. Shlomo Neuman</b> of the University of Arizona and myself. Dr. Butler is well known for his essential book <i>The Design, Performance and Analysis of Slug Tests</i> as well as numerous papers on pumping tests and slug tests. Dr. Neuman, who will be a special guest instructor at the course, is acclaimed for his important contributions to the published literature on the interpretation of pumping tests in unconfined and leaky confined aquifers. I'll be on hand to give personalized instruction on the use of <a href="http://www.aqtesolv.com/training.htm" target="_blank">AQTESOLV</a>.<br />
<br />
<div class="separator" style="clear: both; text-align: center;"><a href="http://upload.wikimedia.org/wikipedia/en/e/e9/Baltimore_Orioles_Script.svg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="http://upload.wikimedia.org/wikipedia/en/e/e9/Baltimore_Orioles_Script.svg" /></a></div>We'll be holding the course at the <b style="color: black;">Camden Yards Conference Event Center</b> in Baltimore's very attractive Inner Harbor area. Camden Yards is the highly regarded ballpark of the <b><span style="color: #b45f06;">Baltimore Orioles</span></b>; as a bonus, course participants will have a special opportunity to attend an evening baseball game on Day 2 of the course.<br />
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For more information and to register for the course, please visit the Midwest Geosciences <a href="http://www.midwestgeo.com/courses/aquifer2012-baltimore.php" target="_blank">web site</a>. I hope that you can join us!hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-61126665250977976002011-10-11T08:39:00.000-05:002012-06-23T17:03:46.480-05:00Fort Collins 2011I'm back from another well-attended aquifer testing short course held at the headquarters of In-Situ, Inc.on October 5 and 6, 2011 and the sixth consecutive year that we've traveled to Ft. Collins, CO to present <i><b>Aquifer Testing for Improved Hydrogeologic Site Characterization Featuring AQTESOLV and the In-Situ LevelTROLL</b></i>.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjrachyPwCAFHALtNNg9i19-Zaiwsm8vwru7uF7E-ejeSpsyKExuMDWlhh_XcdXB51IgF-lC_Zm5sxORM48_ej_u__jW0OAd1v4_0QlAZ4hzEHDYwOmgLixhNZFpBxCktnsON6Jn684athn/s1600/usbr-agarwal-cooper-jacob.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="256" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjrachyPwCAFHALtNNg9i19-Zaiwsm8vwru7uF7E-ejeSpsyKExuMDWlhh_XcdXB51IgF-lC_Zm5sxORM48_ej_u__jW0OAd1v4_0QlAZ4hzEHDYwOmgLixhNZFpBxCktnsON6Jn684athn/s400/usbr-agarwal-cooper-jacob.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Analysis of recovery data combining Agarwal method and derivative analysis.</td></tr>
</tbody></table>
The course covered topics relating to designing, performing and analyzing both slug tests and pumping tests and included hands-on use of <a href="http://www.aqtesolv.com/">AQTESOLV</a> as a teaching tool. As part of my lectures, I spent a good deal of time going over the finer points of diagnostic methods for pumping tests including <a href="http://www.aqtesolv.com/pumping-tests/derivative-analysis.htm" target="_blank">derivative analysis</a>, a technique widely practiced in the petroleum industry for well test analysis. I further introduced the class to the <a href="http://www.aqtesolv.com/recovery_tests.htm#Agarwal_Method_of_Recovery_Analysis">Agarwal method</a> for analyzing recovery tests which also drew a lot of attention.<br />
<br />
Thanks to all who attended the course and to In-Situ for hosting us! I look forward to doing it again next year.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-42405185716596137622011-08-30T17:49:00.000-05:002013-11-10T05:53:37.548-05:00Enhancing Reliability of Slug Test Data AnalysisData from an <a href="http://www.aqtesolv.com/slug-tests/overdamped-slug-tests.htm" target="_blank">overdamped slug test</a> in a well with a fully submerged screen (screen below water table) may exhibit a concave upward appearance on a plot of log normalized head vs. time. The curvature can make analysis by straight-line methods such as <a href="http://www.aqtesolv.com/bouwer-rice.htm" target="_blank">Bouwer and Rice (1976)</a> somewhat ambiguous.<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiA_y9q95lHs-8hyphenhyphenOY_Kwd4XvUH3Yvve0tcMpHoZKKJKxiR8_RhocdDeQ4-MEi6ZO5Jg3qbpGEDLdLwc3jtuUj-2mqDCm_Vfp9I_CBqziqx0OBfNOuHYjQjd2mvkIbsEZqiWWq6VRKwrzlX/s1600/recommended-head-range-bouwer-rice.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="250" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiA_y9q95lHs-8hyphenhyphenOY_Kwd4XvUH3Yvve0tcMpHoZKKJKxiR8_RhocdDeQ4-MEi6ZO5Jg3qbpGEDLdLwc3jtuUj-2mqDCm_Vfp9I_CBqziqx0OBfNOuHYjQjd2mvkIbsEZqiWWq6VRKwrzlX/s400/recommended-head-range-bouwer-rice.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Analysis of slug test data using recommended normalized head range.</td></tr>
</tbody></table>
Butler (1998) suggests matching straight-line slug test solutions to data within <b>recommended normalized head ranges</b> to overcome ambiguity associated with slug test data curvature and thereby enhance the reliability of data analysis. <b>AQTESOLV</b>, <a href="http://www.aqtesolv.com/slug_test_analysis.htm#Best_slug_test_analysis_software">advanced software for slug test analysis</a>, includes the recommended normalized head ranges to assist you with <a href="http://www.aqtesolv.com/visual_curve_matching.htm">visual curve matching</a>.<br />
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Learn more about <a href="http://www.aqtesolv.com/slug-tests/recommended-normalized-head-ranges.htm">recommended normalized head ranges</a> and <a href="http://www.aqtesolv.com/slug-tests/slug-tests.htm" target="_blank">slug testing</a> in <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm">Aquifer Testing 101</a> at the <a href="http://www.aqtesolv.com/">AQTESOLV web site</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-48058983528071039282011-07-20T10:53:00.022-05:002011-11-04T14:53:43.979-05:00Summit in Lawrence, KansasOn today's date in 1969, Neil Armstrong made history by becoming the first man to walk on the moon. Forty-two years later, July 20th marks another red-letter day with the conclusion of the 1<sup>st</sup> Lawrence Summit hosted by Jim Butler and attended by Dan Kelleher and myself. The summit met its primary goal of laying the groundwork for future aquifer testing short courses around the world.<br />
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="clear: right; float: right; margin-bottom: 1em; text-align: right;"><tbody>
<tr><td style="text-align: center;"><a href="http://www.kgs.ku.edu/Hydro/Publications/OFR00_62/gifs/figure2.jpg" imageanchor="1" style="clear: right; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img border="0" height="240" src="http://www.kgs.ku.edu/Hydro/Publications/OFR00_62/gifs/figure2.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">GEMS Research Site (Butler et al. 2000)</td></tr>
</tbody></table>Unforgettable moments during the visit included a tour of the venerable Kansas Geological Survey and its GEMS research site, a view of the Allen Field House from Jim's bleacher seats ("Rock, Chalk, Jayhawk!") and a reverential pilgrimage to the James Naismith ("Inventor of Basketball") Memorial. Without question, though, the unsurpassed highlight of the summit was the delightful sushi dinner served to perfection by Jim's daughter, Mai. Many thanks to Jim and wife Yun for their warm hospitality throughout the Lawrence Summit!<br />
<div class="separator" style="clear: both; text-align: center;"></div>hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-89030996745228236262011-07-14T21:26:00.001-05:002013-10-31T19:04:25.866-05:00Agarwal Recovery MethodIn <a href="http://aqtesolv.blogspot.com/2011/07/analyzing-recovery-tests.html">yesterday's post</a>, I presented <a href="http://www.aqtesolv.com/pumping-tests/recovery-tests.htm">three different methods for analyzing recovery tests</a>. Today, I will focus on the <b>Agarwal recovery method</b> which has been used by petroleum engineers for over 30 years. Agarwal (1980) devised a simple yet powerful data transformation for the interpretation of recovery tests. The transformation, known as Agarwal equivalent time, allows one to analyze recovery data with standard type curves developed for drawdown data.<br />
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The following figure illustrates the simplicity of the Agarwal method in the analysis of a recovery test. In this example, I matched the familiar Theis type curve, normally applied to drawdown data, to estimate aquifer properties from recovery test data (USBR 1995).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhq10tm_DW9NBJiFTrNRke7QJNKEaIM7sISW5lYOtUnP6CIwFKb3pvSdto4PVQh_Io93SZrFKfjq654-1cEbcKVmGC5z5xIh58Vd9b2eaUBe4d4jJKCUe2MTi1aBmMg80PPVQMuFe3bYq9w/s1600/usbr-theis-agarwal.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="243" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhq10tm_DW9NBJiFTrNRke7QJNKEaIM7sISW5lYOtUnP6CIwFKb3pvSdto4PVQh_Io93SZrFKfjq654-1cEbcKVmGC5z5xIh58Vd9b2eaUBe4d4jJKCUe2MTi1aBmMg80PPVQMuFe3bYq9w/s400/usbr-theis-agarwal.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Agarwal recovery analysis using Theis (1935) solution.</td></tr>
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Many different pumping test solutions may be used in conjunction with the Agarwal technique as well as diagnostic methods such as <a href="http://www.aqtesolv.com/derivative_analysis.htm">derivative analysis</a>. The figure below shows recovery and derivative data matched together with the Cooper-Jacob straight-line solution.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgP-4Jtbp0UYW_DRH3W0IAKS26VrFTAn57Q1VOsqr8oOtkHi8MVrx-_ImbeEcGqBOnpHe3YynkwQdBd-WXRZ1TKyzsZxtW4RMl7EF-TYkMs95yQua9EmGEfaorLhUUeJ0KCWYWU4W901cao/s1600/usbr-agarwal-cooper-jacob.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="257" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgP-4Jtbp0UYW_DRH3W0IAKS26VrFTAn57Q1VOsqr8oOtkHi8MVrx-_ImbeEcGqBOnpHe3YynkwQdBd-WXRZ1TKyzsZxtW4RMl7EF-TYkMs95yQua9EmGEfaorLhUUeJ0KCWYWU4W901cao/s400/usbr-agarwal-cooper-jacob.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Agarwal recovery analysis using Cooper-Jacob (1946) solution with derivative.</td></tr>
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Recovery test analysis with the Agarwal equivalent-time method is available in <a href="http://www.aqtesolv.com/recovery_tests.htm">AQTESOLV v4.x</a>. This <a href="http://www.aqtesolv.com/tour.htm#Best_aquifer_test_analysis_software">advanced aquifer test analysis software</a> allows you to estimate aquifer properties by matching both recovery and derivative data together.<br />
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Learn more about the <a href="http://www.aqtesolv.com/pumping-tests/recovery-tests.htm">Agarwal method</a> in <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm">Aquifer Testing 101</a> at the <a href="http://www.aqtesolv.com/">AQTESOLV web site</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0tag:blogger.com,1999:blog-5531985247204766942.post-33934801050480982202011-07-13T17:31:00.011-05:002013-10-08T06:03:17.146-05:00Analyzing Recovery TestsDid you know that <a href="http://www.aqtesolv.com/">AQTESOLV v4.x</a> provides three different methods for the analysis of <a href="http://www.aqtesolv.com/recovery_tests.htm">recovery tests</a>?<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEguZKVXqWGdkDMkuayJOi9BAHK6AC1HRC9f9bRVBXmt1-apmiF-XBX6TImZv1Hmwrv4ACAFlmKVISpqCv_SVxHJ7uN_-J_mbEtAu5UN_IIWgJ_Ioov7VD81hb5lU0ZWU0yyjY15evZH7HCq/s1600/usbr-combined-analysis-theis.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="244" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEguZKVXqWGdkDMkuayJOi9BAHK6AC1HRC9f9bRVBXmt1-apmiF-XBX6TImZv1Hmwrv4ACAFlmKVISpqCv_SVxHJ7uN_-J_mbEtAu5UN_IIWgJ_Ioov7VD81hb5lU0ZWU0yyjY15evZH7HCq/s400/usbr-combined-analysis-theis.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Method 1: Combined analysis of drawdown and recovery data.</td></tr>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgscalFc7UQ7s8mq9oJhnsdMwDgcwTAdJksM3ThwwpcyZl7tCQnfvG88DqNQASD2BDIPvAYqjLATFE-db_KxxLHZQOKw9yk3Tkd1fksAvqZ2VSBM8a_8cPybs_tT7tTDb2kvEnKb7cw8lf1/s1600/usbr-theis-residual-drawdown.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="248" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgscalFc7UQ7s8mq9oJhnsdMwDgcwTAdJksM3ThwwpcyZl7tCQnfvG88DqNQASD2BDIPvAYqjLATFE-db_KxxLHZQOKw9yk3Tkd1fksAvqZ2VSBM8a_8cPybs_tT7tTDb2kvEnKb7cw8lf1/s400/usbr-theis-residual-drawdown.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Method 2: Analysis of residual drawdown data.</td></tr>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhq10tm_DW9NBJiFTrNRke7QJNKEaIM7sISW5lYOtUnP6CIwFKb3pvSdto4PVQh_Io93SZrFKfjq654-1cEbcKVmGC5z5xIh58Vd9b2eaUBe4d4jJKCUe2MTi1aBmMg80PPVQMuFe3bYq9w/s1600/usbr-theis-agarwal.gif" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="243" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhq10tm_DW9NBJiFTrNRke7QJNKEaIM7sISW5lYOtUnP6CIwFKb3pvSdto4PVQh_Io93SZrFKfjq654-1cEbcKVmGC5z5xIh58Vd9b2eaUBe4d4jJKCUe2MTi1aBmMg80PPVQMuFe3bYq9w/s400/usbr-theis-agarwal.gif" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Method 3: Analysis using Agarwal (1980) method.</td></tr>
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The foregoing figures illustrate the use of the three recovery test methods in the analysis of a field example reported in the <i>Ground Water Manual</i> (USBR 1995). The results show that one may obtain consistent aquifer property estimates with all three techniques.<br />
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Learn more about the <a href="http://www.aqtesolv.com/pumping-tests/recovery-tests.htm">three methods of recovery analysis</a> in <a href="http://www.aqtesolv.com/aquifer-tests/aquifer-tests.htm">Aquifer Testing 101</a> at the <a href="http://www.aqtesolv.com/">AQTESOLV web site</a>.hydrosolvehttp://www.blogger.com/profile/16677271373093317184noreply@blogger.com0