Ms. Hazelle Ko, a graduate student in the Environmental Sciences (EV) Program at the University of Guam, successfully defended her thesis on November 21, 2024. Her thesis focuses on chloride trends in 9 wells located in the Yigo-Tumon Basin, and evaluated impacts of natural factors such as ENSO, rainfall  and sea level, and well production rates on chloride concentrations. In Ms. Ko's thesis, she found that chloride concentrations in the wells studied have increased over 49 years, influenced by production rates, well design, and sea level changes leading to saltwater intrusion. While…