Measurement of Road Salts in Water
Course: 14.332 - Environmental Engineering Lab
Semester: Spring 2006, Spring 2007, Spring 2008
Instructor: Clifford Bruell
Partner:Town of Dunstable and Board of Health
The Town of Dunstable Board of Health partnered with the Environmental Engineering Lab course students through Dr. William Moeller’s long time participation on the town board and board of health. The Environmental Engineering Lab students conducted a Measurement of Road Salts in Water, Laboratory Exercise as a service-learning research and education activity. The Town of Dunstable had expressed concerns regarding potential fresh water well contamination from road salts during the New England winter season. The town Board of Health invited the students to gather, analyze and compare well water samples. The laboratory class analyzed water using chloride probes to screen well water samples, taken at numerous locations in Dunstable, MA, for evidence of NaCl contamination resulting from road deicing activity. The goal of the screening effort was to identify the extent and intensity of NaCl contamination and to determine the location of potential “hot spots”.
This SLICE project provided students with the opportunity to learn more about the proper calibration and use of specific ion probes (i.e., chloride probe) and associated analysis of field data. In addition, the community obtained an initial screening of the NaCl levels that reported elevated NaCl levels occurring at six of the sixteen locations sampled within Dunstable, MA. A letter was sent to the town board along with a copy of a representative student laboratory report indicating NaCl levels and locations within Dunstable, MA. Results and analysis of additional samples collected at additional locations conducted by the instructor were also shared with the town for use in local decision-making. This was the first time that this type of service-learning project was conducted within the town of Dunstable. In the future, there is hope to expand the scope of the project by linking the sample analysis of both ground waters and surface waters not only to the topography but also to the hydrology of Dunstable (i.e., to conduct some mass balances of NaCl movement into and out the region). Hopefully, such an analysis may be conducted in conjunction with the 14.460 Water Resources Engineering courses taught by Prof. Zhang.
The Environmental Engineering laboratory class analyzed water using chloride probes to screen well water samples, taken at numerous locations in Dunstable, MA, for evidence of NaCl contamination resulting from road de-icing activities. The goal of the screening effort was to identify the extent and intensity of NaCl contamination and to determine the location of potential “hot spots”. Copies of two representative students laboratory reports were provided the town of Dunstable in which NaCl levels and locations were indicated. In addition, analyses of additional well samples were provided by the course professor. Students reported that they enjoyed the laboratory because it involved the analysis of real world samples and that they were grateful that their analysis results would be used to help identify and solve a real problem. Since this laboratory involved the analysis of real world samples and the data was of real value the students were reported as more engaged by the professor.
Learning objectives met by the S-L project:
- Students learned the proper calibration and use of specific ion probes (i.e. chloride probe) and analysis of field data Community objectives met by S-L project:
- The community obtained screenings of the NaCl levels in wells selected by the BOH
This is the third time that this service-learning project has been run by the Environmental Engineering laboratory class. They now have historic data over a three-year period, but, this year, for the first time, they have compiled some data from both ground waters and surface waters and have also obtained details of individual well construction. With this additional data it may be possible to conduct a more meaningful analysis of the NaCl hydrology of Dunstable, i.e., to conduct some mass balances of NaCl movement into and out the region. Hopefully, this analysis will be conducted in the course 14.460 Water Resources Engineering in the future. The class is still going to deliver copies of two representative students laboratory reports to the town of Dunstable in which NaCl levels and locations were indicated. The chief barrier of this project has been reported to be that the “sample collection (by professor) involves driving and having homeowners grant permission to sample their wells on their property”, nevertheless, this shows the great commitment that our professors have to these service learning projects. It is also worthy of repeating that this is the third year that this project has been assigned and completed, which is another example of commitment by the professor, students and community – the partnership has demonstrated to be strong and lasting.