Estimating confined aquifer parameters using a simple derivative-based method.

Area of Science:

• Hydrogeology
• Geotechnical Engineering

Background:

• Confined aquifer parameters like transmissivity and storage coefficient are crucial for groundwater management.
• Existing methods for estimating these parameters from pumping tests have limitations, including data range restrictions and subjective analysis.

Purpose of the Study:

• To introduce a novel, objective derivative-based method for estimating confined aquifer parameters.
• To overcome the drawbacks and subjectivities associated with traditional pumping test analysis techniques.

Main Methods:

• A derivative-based approach is presented to analyze drawdown data during pumping tests.
• Aquifer parameters are estimated using developed equations derived from the least squares optimization approach.
• The method utilizes the non-linear relationship between drawdown time derivatives and pumping time.

Main Results:

• The new method provides acceptable estimation accuracy for confined aquifer parameters.
• It is applicable to the entire drawdown data range, unlike some existing methods.
• Parameter estimation is minimally affected by the drawdown time interval due to the analytical nature of derivative calculations.

Conclusions:

• The proposed derivative-based method offers a simplified and objective approach to determine confined aquifer parameters.
• It eliminates the need for curve matching, initial parameter guesses, and complex calculations, enabling on-site analysis.
• This method enhances the efficiency and reliability of pumping test interpretations in hydrogeology.