Validation of Student Generated Data for Assessment of Groundwater Quality

As part of a research project to evaluate the effects of sand and gravel mining on water quality, students were trained to analyze their own drinking water for simple quality indicators. Indicators analyzed were pH, conductivity, hardness, nitrate, chloride, and dissolved iron. Approximately 523 analyses were completed by students between 2006 and 2010. A total of 208 sample splits were analyzed in a laboratory to evaluate student accuracy and precision for pH, hardness, chloride, and nitrate. Overall students produced very good quality data for pH and conductivity. Hardness, chloride, and nitrate, all of which were quantified using titrations, were less precise and accurate than laboratory samples. The student results overall were useful with the limits of method uncertainties. As an experiment to teach students about water quality the results are very good. Validation of results for use in additional research indicates that additional quality control or new methods will be needed to improve the accuracy of student analyses.