At Conserve School we are very fortunate to have our very own waste water treatment facility right here on campus. This allows us to reduce our environmental impact by returning water to the environment within a half mile of the well where it is extracted. What makes this treatment facility unique is that it is able to remove solid waste and nutrients with the help of industrious naturally occurring bacteria and plants. AP Environmental Science students received a tour of this facility from science teacher Andy on Thursday morning.
During the tour students learned about the process by which waste and nutrients are broken down and removed in the green machine. The process begins with a closed anaerobic stage in which water is stored in a tank deficient in oxygen where anaerobic bacteria can begin the process of breaking down the waste and removing nutrients. Then water flows into the open anaerobic tank where a similar process continues; however, this time the tank is capped by a roof of soil. The soil traps gasses that are produced as the bacteria work away. The soil must stay moist for this to work, so plants are grown in the soil to indicate the soil moisture. Moving on to the next tank, students saw a giant banana palm growing out of the open aerobic tank. In this tank aerobic bacteria and plants extract more nutrients from the water. The plant roots actually create a three dimensional structure in which the bacteria can live and feed on the nutrients, and the plants also convert some of the nutrients in the water into plant tissue. Next down the line are the clarifying and polishing tanks where the process is completed by allowing any leftover matter to settle to the top or bottom where it is skimmed off. Then the water is delivered into the environment in one of 5 septic fields that are used on a rotating basis.
When the students returned to the classroom, they compare this system with traditional septic tank systems. Andy described Northwoods zoning regulations and the social aspects of environmental science. His whiteboard illustrations and descriptions of historical and current zoning laws got the students thinking about the complex, political, and interdisciplinary nature of environmental issues. Compromise is often necessary, and it is important to consider the issue from many different perspectives. These real life lessons will help the students to understand how they can make their own voices heard when they return home at the end of the semester.
~ Graduate Fellow Heather