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Alex Guzman & Cassidy Yueh

Project Summary
This study showed that it is theoretically possible to recover enough methane gas from fish waste to power an aquaponics system. Work involved parameterizing an interactive mathematical STELLA model to enable aquaponics managers to determine the optimal system volume, numbers of fish, and pump size for the most efficient aquaponics system, which is practical as sustainable food production increases in importance. Results to determine effects of feeding rates on fish size and waste production showed that feeding rates directly affect fish growth (p = 0.0047), but feeding rates did not affect waste production (p = 0.3976). The STELLA model we created showed that the rate of energy production increased less than the total energy demand as the size of an aquaponics system increases; therefore, this study shows that larger aquaponics systems are not more energy efficient than smaller aquaponics systems in anaerobically producing methane gas from aquaponics waste. Results from treating waste using thermochemical hydrolysis showed no significant increase in methane gas production (p = 0.6805). This information will be useful to aquaponics managers as they use our model to design an efficient aquaponics system. Finally, an inexpensive prototype anaerobic digester was engineered for methane gas production from waste that can be used by aquaponics farmers.
 Alex Guzman

If one were to ask my peers to describe me, common words that would inevitably be brought to attention in the otherwise long list of mediocre traits would be chill, funny, laid back (just check page 219 of the 2016 yearbook), and musical. Outside of my academic interest such as environmental science and history, the last characteristic mentioned above (musical) truly describes my principal interest. I Love Music! More than I love listening to my favorite artists Bob Dylan, The Beatles, and The Grateful Dead, songwriting is a passion of mine. I play guitar and drums, but it’s relatively difficult to write a song on drums, so one may commonly find me strumming away on my mom’s old acoustic YAMAHA guitar from the 80s. I also participate in athletics. I once had dreams of conjuring the heroism of a gladiator and playing sports like hockey and football (I actually played hockey in the third grade) but my scrawny legs kept me chained to the less romanticized sports of cross country and long distance track. Nevertheless, I fell in love with running and ran throughout my high school career. I am also an avid outdoors fan! I joined Boy Scouts at the age of 11. Since, I have spread my wings and soared my way to the rank of Eagle Scout. My experiences in scouting and adventures outdoors have sparked my interest in environmental issues, which led me to pursue environmental/sustainability-focused research through the Advanced Science Research program.
   Cassidy Yueh

My name is Cassidy Yueh, Class of 2017. I was born in Seattle, Washington, and lived there for eight years, and am of Brazilian, Manchurian, and Taiwanese descent, but I am only fluent in English. I have a younger brother I call Stu. I springboard dove for the Breck Girls Swim and Dive team for three years. Currently, I am a Track and Field thrower, Breck Mock Trial co-captain, a participant in the Art Club, Environmental Club, and the Photography Club, the founder of the Psychology Club, the founder of the Mental Health Awareness Club, and I am a Poetry and Art Section Editor for the Ars Nova Magazine Club. My scientific areas of interest comprise environmental science focusing on sustainability and alternative materials engineering for a better future, including purification of waste and generating biofuels. In my free time, I draw, read botany books, and may or may not play 2048. My favorite animals are Felis catus and Odontodactyllus scyllarus. I am quite the squirrel enthusiast, and I particularly enjoy the Jelly Belly Candy Company™ black licorice jelly bean.
Honors & Awards
Alex Guzman (2016) & Cassidy Yueh (2017) worked in the Biology Department at the University of St. Thomas under the guidance of Dr. Gaston Small. Alex and Cassidy were selected as Siemens Competition regional semifinalists and Intel ISEF alternates. They also won a Bronze Medal at the International Sustainable World Engineering, Energy, Environment Project Olympiad (ISWEEEP). At the regional science fair, they received the 3M Inventor Award, the 3M Renewable Energy Award, United States Navy and United States Marine Office of Naval Research Award, American Fisheries Society Aquatic Sciences Achievement Award, and qualified for the 3M Young Inventor Recognition Event. At the state science fair, they won a Third Place Bronze Grand Award, the SAS/JMP Institute Data Visualization & Discovery Award, and the American Meteorological Society Special Award. They also participated in the North Central Tri-State JSHS Competition. Alex will be attending the University of Puget Sound.