Using spring water chemistry to understand groundwater inputs
The assignment will begin with teaching proper water collection and use of equipment for hydrochemical field work. Once the class is familiar with sample collecting technques, the class takes a field trip to several springs within the Madera Limestone, Sandia Mountains New Mexico. Collecting waters and obtaining hydrochemical field parameters for each spring location as well as collecting groundwater from one well in the same aquifer. Returning to the lab and preparing and running samples for ion analysis.
Spring waters will then be compared to well water and average precipitation data available from the USGS. Geochemical modeling will then be completed to understand the proportion of aquifer, precipitation and possible deeply sourced waters found in the spring waters.
The outcomes include 1) teaching proper sampling techniques 2) proper preparation of samples for ion analysis 3) Geochemical modeling to understand mixing
This would be an upper level (300) undergraduate course in geochemistry or environmental sciences. Chemistry and hydrology would be required, but sampling techniques would be taught during this course.
Skills and concepts that students must have mastered
Field sampling and equipment management. Sample preparation for ion analysis. Geochemical modeling using Phreeqci and/or Geochemist WorkBench.
How the activity is situated in the course
The exercise would be a culminating project that would provide students with opportunity to work in groups and write a final project paper explaining the mixing proportion.
Content/concepts goals for this activity
Hydrochemistry of spring waters. Hydrochemical field sampling techniques and sample analysis in hydrochemical lab.
Higher order thinking skills goals for this activity
Analysis of hydrochemical results and critical evaluation and comparison of model results
Other skills goals for this activity
Working with hydrochemical field equipment as well as lab equipment for titration and ion analysis. Geochemical modeling using Phreeqci and/or Geochemist WorkBench
Description and Teaching Materials
Teaching Notes and Tips
Hydrochemical results as well as geochemical modeling will provide details to assess if 1) samples were properly collected and dilutions prepared appropriately 2) geochemical modeling results have proper saturation indices and mixing proportions
References and Resources