Geology 210

Aquifer Characterization


California State University, Sacramento


Week 4


- Data logger demonstration

- Three hour drawdown test

- Distance drawdown solution




Upon completion of this unit students should be able to:

  • Service and calibrate vented and non-vented pressure transducers

  • Modify the line code that controls a Campbell CR-10 data logger

  • Start, stop and modify a test using a Solinst levelogger

  • Set up and monitor a multi-well aquifer test, then download results


Reading for week 4:

Your readings and references this week come from Fetter, Applied Hydrogeology:


1) General reading on well hydraulics:

Fetter, 4th ed., pp. 190-205


Fetter, 3rd ed., pp. 214-239   


2) Jacob distance drawdown method:

Fetter, 4th ed., pp. 176-177


Fetter, 3rd ed., pp. 227-229



Tuesday (Aug 14):

Guest lecture by Michelle Sneed, USGS Hydrologist.  Michelle will talk to us about data loggers and pressure transducers, and we will calibrate a pressure transducer.


Saturday morning activities (Aug. 18):

Conduct a three hour drawdown test using the extraction well and downhole pump


Field data files from 3 hour drawdown test, Saturday Aug 18:  Hint: Open MS Excel first, then import the file.


Manual measurements (all wells)





Saturday afternoon activities (Aug 18):

Return to Placer Hall, and solve a distance drawdown problem.  Determine T, K and S for the deeper interval.

Semi-log paper for distance drawdown analysis


3 x 5 log paper for Theis type curve fit



Assignment for week 4:

For Tuesday (Aug. 21)


Plot the results of our 3 hour test on 3 x 5 log paper.  We will use this to look for leakage (type curve fit) in class Tuesday evening.  Choose a well or two that have significant drawdown.


3 x 5 log paper for Theis type curve fit


For next Saturday (due Aug. 25)


Use the data that we collected from our 3  hour drawdown test to estimate T, K and S.  Use the Jacob distance-drawdown method.  Try an early solution (10 minutes or less), a medium solution (60 or 90 minutes) and a "long" solution (180 min).  Compare your results.  Is this really a long test?


Format of the report:

Cover page (letter to the client):  Provide a cover letter and company logo that introduces your report to the client.


Introduction and purpose: State the purpose of the study: To estimate T, K and S using a distance drawdown solution (Jacob method).


Hydrogeologic setting: Geologic, hydrologic, land use, construction, hazards, etc. as appropriate.  Which wells did you use?


Methods: Field methods, test parameters (flow rate, time), data loggers used, manual methods


Results: Summarize results, including equations and estimates.  Show a graph of distance-drawdown.


Conclusions and recommendations  Based on distance-drawdown tests at the CSUS wellfield, what is your estimate of T, K and S in the deeper water-bearing interval?


Due date: Saturday, Aug. 25