Abstract
The hydraulic parameters representative of actual aquifer conditions can be obtained through aquifer tests formerly known as pumping tests. Diverse methodologies based on analytical or numerical solutions have been proposed for the interpretation of aquifer tests; however, measurement and model errors are often neglected, which could lead to hydraulic parameter values that do not reflect the aquifer conditions. In this paper, a new alternative is presented for the interpretation of aquifer tests in confined aquifers based on the Cooper–Jacob solution by means of the dynamic Kalman filter and a nonlinear optimization method. This proposal was tested in two previously published case studies; the measured drawdowns were filtered by considering measurement and model errors to match the Cooper–Jacob solution. For the case studies, the results show that filtering the measured drawdowns leads to variations of up to 49.97% in the values for T and 150% for S when compared to the values determined by methodologies that neglect measurement and model errors. A poor match between filtered and measured data reflects large measurement errors and considerable deviations of the aquifer conditions with respect to the proposed model.
Highlights
It has been stated that numerical flow models represent the most advisable and powerful available tool for the adequate evaluation, planning and management of groundwater [1]
In order to calibrate a numerical flow model, the hydraulic parameters can be obtained from aquifer tests, formerly known as pumping tests, which evaluate the response of an aquifer by extracting water through a pumping well
The Kalman filter-based procedure proposed in this paper represents a new alternative for the interpretation of aquifer tests in confined aquifers considering model and measurement errors
Summary
It has been stated that numerical flow models represent the most advisable and powerful available tool for the adequate evaluation, planning and management of groundwater [1]. In order to calibrate a numerical flow model, the hydraulic parameters can be obtained from aquifer tests, formerly known as pumping tests, which evaluate the response of an aquifer (time-drawdown data usually measured at observation wells) by extracting water (at a constant flow rate) through a pumping well. Another option to determine the hydraulic parameters is the execution of permeability tests performed in the laboratory, or alternatively with the use of tracers, from reference tables, or empirical formulas; aquifer tests provide the most representative values for specific aquifer conditions [3,4,5]. They represent the exact solution of a mathematical model that describes the groundwater flow in the vicinity of a pumping well following particular assumptions
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call