Modeling the Breakdown of Pharmaceuticals in East Gemini Lake

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Computer Sciences | Physical Sciences and Mathematics


Mike Heroux, Computer Science


In addition to theory and experimentation, computer modeling has emerged as a third approach to scientific discovery. The Virtual East Gemini Lake Project is the beginning of an effort to develop a computer model of East Gemini Lake at Saint John's University in order to simulate the flow and breakdown of pharmaceuticals in the St. John's wastewater treatment system. The project seeks to increase understanding of how pharmaceuticals enter the system, breakdown, or otherwise leave it. The final goal of the project is to be able to simulate speculative changes to the Saint John's wastewater treatment system through a model of East Gemini Lake and to seek changes that may improve the quality of our water supply, with the possibility of providing guidance for water treatment efforts beyond the Saint John's community. In order to begin constructing a model for East Gemini Lake, a program was developed which is able to calculate the rate of direct photolysis in a water body for a particular chemical. This program was created by following the work of Richard Zepp and David Cline. The program calculates photolysis rates as well as half-lives for a chemical as a function of location on Earth, time of day and year, depth of the chemical in the water body, the molar extinction coefficient of the chemical, the quantum yield of the chemical, and the absorption coefficient of the water body in question.