Drinking Water Quality: An Interdisciplinary Research Experience of Introductory Geology and Chemistry Classes

Robert Shuster, University of Nebraska at Omaha

Summary

At the University of Nebraska at Omaha, we have involved students in introductory Geology and Chemistry classes in an interdisciplinary study of drinking water quality. The goals of this project are to introduce the students to the scientific method, get them to actually "do" relevant science, and show how science affects their lives. We have also used this exercise to help some students overcome their fear of science by allowing them to actively learn science, rather than absorb it in a passive fashion.

Context

Audience

These courses are mainly populated by first or second year students. There is typically a significant population (average 15%) of pre-service elementary and secondary level teacher education majors who take the introductory Geology classes. The majority of students in these courses are non-majors, taking the course to fulfill a natural science requirement. Interestingly, we have been able to attract majors with this exercise. The Chemistry course serves mainly pre-health students, engineering majors, and other STEM area majors.

Class Size

More than 50 students

How the Activity is Situated in the Course

This activity is part of the Geology courses, with at least one class time (two is better) dedicated to discussion of the project. It is usually scheduled to occur when we are discussing water topics in the Geology courses. For the Chemistry course, it comprises one of the labs, specifically the one on ion chromatography and capillary electrophoresis.

Goals

• Have students learn the scientific method and learn how scientific research studies are designed and carried out.
• Teach students the interdisciplinary nature of science and scientific research (that there is a reason for them to take Chemistry classes).
  
• Teach students about sample collection protocols.
• Develop data handling and analysis skills.
• Develop an appreciation for the power and dynamics of working in groups.
• Develop discussion and presentation skills.
• Have students learn about how to handle various types of error and uncertainty in data.
• Incite interest and enthusiasm for science and possible choice of science as a career.

Description

This exercise involves students from two different departments to work together on a research project, a study of drinking water quality in the Omaha area. Students from an introductory Geology course collect drinking water samples from around the Omaha area. They collect multiple samples if their homes have water softening systems, water filtration systems, or from the same source, to serve as a replicate analysis. Samples of well water are also collected to compare to the municipal water. These samples are taken to the Chemistry class, where students analyze the samples using ion chromatography in one of their labs. The results of these analyses are sent in spread-sheet form to the Geology class, who analyzes the results. Questions asked are: What is the effect of water-softening on water composition?; What is the effect of filtering on water quality?; Is there any geographic control on the composition of the drinking water?; and What is the difference between municipal water and well water? These questions lead to the discussion of how water-softeners work (zeolites) and filtering systems work, what geologic factors control the composition of drinking water, and why there might be a variation geographically in Omaha in drinking water composition. The class is divided up into teams to discuss one of these topics. A volunteer then presents the results to the rest of the class and then a discussion ensues.

Finally, volunteer teams from Geology and Chemistry develop presentations to deliver to the other classes. The Chemistry presentation involves ion chromatography, analytical methods, and analytical error. The Geology student presentation involves the analysis of the data.
Work accomplished in this interdisciplinary study was the basis of a successful grant proposal written to the National Science Foundation for an ICP-MS.

Notes, Tips, and Logistical Considerations

• A research exercise like this requires a close working relationship between Geology and Chemistry Departments.
• Deciding exactly when samples should be collected and analyzed and scheduling class discussion time needs to be done early in the semester to make sure that conflicts do not occur.
• We found that this exercise worked much better with specific, written instructions on sample collection.
• A simple web site where students could enter data (sample number, location, type, etc.) facilitated organization of the data. This same web site was used by Chemistry students to enter analytical data.
• The assessment plan helped us develop and modify the project as time went on.
• This project could be modified to fit any local situation. For example, the reason we look at geographic differences in water quality is that Omaha has two (now three) separate water sources: well fields next to the Platte and Elkhorn Rivers and surface water from the Missouri River.
• Be prepared to work closely with student groups at first, to make sure they are doing the data analysis correctly. Many students also are at a complete loss of how to begin. A little care in the organization of the student groups can help in these situations (make sure there is a class leader in a group if possible). This can help keep the groups on task.
• Be sure to be ready to discuss with students why a simple, single answer or explanation might not exist.

Assessment

• The student outcomes of this project were evaluated through an anonymous student-feed back survey and student focus group discussions.
• The survey was a Likert-scaled instrument developed for this project by the Center for Assessment and Evaluation of Student Learning at WestEd.
• Separate focus groups were composed of 6 - 10 students from each class and lasted for approximately 30 minutes. These group discussions were led by faculty not directly involved in the research project. These sessions were recorded and transcribed and the results were evaluated by an external evaluator.
• A more complete discussion of the instruments used and our results can be found at Richter-Egger et al., 2010.

Teaching Materials

• A good working relationship with your Chemistry Department
• Adequate analytical equipment for the water analyses
• A variety of sources for drinking water (softened vs. non-softened, filtered vs. non-filtered, well water vs. municipal water, etc.)
  

References

Richter-Egger, Dana L., Hagen, James P., Laquer, Frederic C., Grandgenett, Neal F., and Shuster, Robert
D., 2010, Improving student attitudes about science by integrating research into the Introductory Chemistry Laboratory: interdisciplinary drinking water analysis: Journal of Chemical Education,
v. 87 (8), pp 862-868.

Shuster, Robert D., Hagen, James P., Laquer, Fredric C., and Richter-Egger, Dana L., 2004, Learning science by doing science: Research inquiries in introductory science: 10th National Conference, Council on Undergraduate Research, Workshop and Poster Abstracts, p. 38.

Shuster, Robert D., and Richter-Egger, Dana, 2007, Early undergraduate research in introductory geology and chemistry classes, Geol. Society of America, Abstracts with Programs, v. 39, no. 6, p. 247.