A simple borehole dilution technique in measuring horizontal ground water flow

Area of Science:

• Hydrogeology
• Environmental Science
• Analytical Chemistry

Background:

• Borehole dilution techniques are used to monitor groundwater movement into wells.
• Estimating horizontal Darcy flow velocity is crucial for aquifer characterization.
• Previous methods used saline or deionized water, requiring distinct fluid properties.

Purpose of the Study:

• To introduce a new, practical borehole dilution technique.
• To utilize Brilliant Blue FCF dye and a photometric sensor for groundwater velocity measurement.
• To demonstrate the technique's effectiveness with real-world examples.

Main Methods:

• Establishing a uniform fluid column condition within a monitoring well.
• Introducing Brilliant Blue FCF dye to mark the fluid column.
• Employing a custom-built photometric sensor to track dye dilution over time.

Main Results:

• The technique successfully monitored the rate of groundwater inflow.
• Dilution of Brilliant Blue FCF dye correlated with groundwater movement.
• Two practical examples validated the method's application.

Conclusions:

• The Brilliant Blue FCF dye dilution method provides a viable alternative for measuring groundwater flow velocity.
• This technique offers a safe and effective approach for hydrogeological assessments.
• The photometric sensor enhances the accuracy and practicality of borehole dilution measurements.