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Meaningful Interpretation of Step‐Drawdown Tests
Groundwater, 1995Abstract From a critical review of literature it is concluded that the available methods of analyzing step‐drawdown tests produce information which can be misleading, inaccurate, or meaningless. Calculation of the total well loss from step‐drawdown tests, on the other hand, provides a meaningful evaluation of well performance but is ...
M. Kawecki
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Analysing step-drawdown tests in heterogeneous aquifers
Quarterly Journal of Engineering Geology and Hydrogeology, 2002All existing methods for analysing step-drawdown test data assume that the aquifer is homogeneous, whereas most real aquifers are heterogeneous. Failure to account for such heterogeneity can lead to erroneous mis-interpretation of step-drawdown test results, which may in turn result in expensive over- or under-design of long-term pumping plant.
Karami GH, Younger PL
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Parameter Estimation for Step‐Drawdown Tests
Groundwater, 1992Abstract Step‐drawdown tests may be used to evaluate the well loss component of the well drawdown and to obtain estimates of the aquifer properties. A procedure that analyzes step‐drawdown tests with pumping stages of unequal time durations was formulated and developed into a computer program; the method is applicable to confined ...
Cem Avci
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An approach to interpretation of step drawdown tests
Hydrogeology Journal, 2006To understand the behaviour of drawdown with discharge under site-specific conditions, a step drawdown test (SDT) was conducted on a tubewell in alluvium near Delhi, India, and the data were analyzed to find the value of well efficiency. The entrance velocity of groundwater into the well screen was computed to see if it exceeded the safety limit of 0 ...
S. Shekhar
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Discussion on ‘The analysis and planning of step drawdown tests’ by L. Clark
Quarterly Journal of Engineering Geology, 1978May I congratulate Lewis Clark on his paper covering the analysis and planning of step drawdown tests. I think the subject of well performance is due for a ‘shake-up’ and this paper will hopefully initiate some useful scientific discussion in the right direction. I have two main criticisms to make.
B. Connorton
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Identification of aquifer and well parameters from step-drawdown tests
Hydrogeology Journal, 2010A new analysis technique has been proposed for interpreting transient step-drawdown test data. The proposed method is based on taking the derivative of the drawdown with respect to time for the entire pumping test period to eliminate the time-independent well-loss terms.
Cem B. Avci, Emin Ciftci, A. Ufuk Sahin
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EDNHAZ: a program for analyzing step drawdown tests
Computers & Geosciences, 1989Abstract This paper presents a FORTRAN program for analyzing step drawdown tests which has some advantages over traditional graphically based methods. A more flexible approach to the planning and execution of stepped pumping tests is possible by using the method of analysis adopted in the program and outlined in the text.
K. J. Vines
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The analysis and planning of step drawdown tests: a clarification
Quarterly Journal of Engineering Geology, 1979I have received letters from Mr D. M. Milne and Dr P. F. Worthington pointing out an error in the application of the analytical methods in this paper, (published in 1977 in Q. Jl Engng Geol . 12 , 125–143). I would therefore like to take this opportunity to clarify the matter.
L. Clarke
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Numerical analysis of step-drawdown tests: Parameter identification and uncertainty
Journal of Hydrology, 2010An inverse, numerical model is presented as an interpretation method for step-drawdown tests. The model consists of an axi-symmetric model to simulate radial flow in a horizontally stratified aquifer, and a nonlinear regression analysis to identify hydraulic parameters and quantify parameter uncertainty.
A. Louwyck, A. Vandenbohede, L. Lebbe
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New Insight Into The Step-Drawdown Test In Fractured-Rock Aquifers
Hydrogeology Journal, 1994Review of the historical development of the step-drawdown pumping test and interpretations of well test data using the step-drawdown method indicates considerable differences in the importance attributed to head losses in the artificial environment (e.g., the gravel pack and screen) in the immediate vicinity of the wellbore and the losses resulting ...
Lee C. Atkinson +2 more
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