In this fictional case study, the state of Oklahoma has profited by giving incentives for companies to build power plants in rural areas of the state. The "scrubbing" systems used to minimize air pollution create potentially hazardous solid waste. To contain this waste, an impoundment facility has been built on unsuitable land from which water-soluble toxins can leach into groundwater. Student teams design a prototype sensor capable of measuring dissolved oxygen and fluorescein dye in water in order to analyze the runoff from the impoundment facility for toxins. The case was developed for an undergraduate laboratory course in photonics for junior- and senior-level students.