
Geology 210 Aquifer Characterization
California State University, Sacramento
Week 4
 Data logger demonstration  Three hour drawdown test  Distance drawdown solution

Objectives:
Upon completion of this unit students should be able to:
Service and calibrate vented and nonvented pressure transducers
Modify the line code that controls a Campbell CR10 data logger
Start, stop and modify a test using a Solinst levelogger
Set up and monitor a multiwell 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. 190205
or
Fetter, 3rd ed., pp. 214239
2) Jacob distance drawdown method:
Fetter, 4th ed., pp. 176177
or
Fetter, 3rd ed., pp. 227229
Activities:
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.
Semilog 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 distancedrawdown 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 distancedrawdown.
Conclusions and recommendations Based on distancedrawdown tests at the CSUS wellfield, what is your estimate of T, K and S in the deeper waterbearing interval?
Due date: Saturday, Aug. 25