THE LIVING FILTER: MONITORING NUTRIENT ACCUMULATION

As global freshwater sources decline due to environmental contamination and a growing population, more sustainable wastewater renovation techniques will need to be applied to ensure freshwater for future generations. Sustainable wastewater disposal is one way to reduce freshwater use and recycle valuable nutrients into the ecosystem simultaneously. One such example of a sustainable solution is called the Living Filter, located on the campus of Pennsylvania State University. For fifty years, Penn State has sprayed treated wastewater onto agricultural fields and forest ecosystems, leaving natural processes to further filter the wastewater. As the wastewater is filtered, it eventually reaches the groundwater where it is pumped for university drinking water again. This cyclical process is deemed sustainable because the freshwater is recycled, providing drinking water to an increasing university population and nutrients to agricultural crops, without causing major environmental catastrophes such as fish kills, eutrophication or groundwater contamination. At first glance this project seems sustainable and effective, but for how long can this setup continue without nutrient overloading and environmental contamination? To be truly declared sustainable, the hopeful answer to this question is indefinitely. The purpose of this project is to evaluate the sustainability of the Living Filter process, examining the cycling and accumulation of nutrients within the system. The goal is to analyze long-term monitoring tools to measure and evaluate ecosystem indicators such as soil nutrient capacities, moisture levels, compaction rates, and conductivities that can be used to declare the process a sustainable solution to wastewater disposal. Comparing data from the initial system installation to present data collected from soil cores and lysimeters will provide essential indicators of changes over time. This is one of the few systems that have data from the past to compare to the present to evaluate the life history and effectiveness of the system. In order to achieve this goal, a multi-disciplinary approach will be used to track nutrient movement from wastewater spray to groundwater, yielding a quantitative nutrient analysis for future wastewater reuse recommendations.