Sanitary Landfills Municipal Solid Waste: Lesson 3b

Objectives Students will understand the basic structure of a sanitary landfill. Students will understand the basic structure of a sanitary landfill. Students will understand the difference between the old style landfill and the sanitary landfill. Students will understand the difference between the old style landfill and the sanitary landfill.

Nevada State Standards: Grades 9-12 N.12.B Students understand the impacts of science and technology in terms of cost and benefits to society. N.12.B Students understand the impacts of science and technology in terms of cost and benefits to society. N.12.B.1 Students know science, technology, and society influenced one another in both positive and negative ways. E/S N.12.B.1 Students know science, technology, and society influenced one another in both positive and negative ways. E/S N.12.A.5 Students know models and modeling can be used to identify and predict cause-effect relationships. I/S N.12.A.5 Students know models and modeling can be used to identify and predict cause-effect relationships. I/S E.12.C.5 Students know soil, derived from weathered rocks and decomposed organic material, is found in layers. E/S E.12.C.5 Students know soil, derived from weathered rocks and decomposed organic material, is found in layers. E/S

Lesson Draw layers of the sanitary landfill. Draw layers of the sanitary landfill. Gather students in groups of 5, depending on class size. Gather students in groups of 5, depending on class size. Pass out prefilled reusable grocery bags. Pass out prefilled reusable grocery bags.

Lesson Mark 2 from top of bottle with marker. Mark 2 from top of bottle with marker. Use scissors or knife to cut the top of the bottle off. Use scissors or knife to cut the top of the bottle off. Cut nylon hose into 2 squares, 2 per group. Cut nylon hose into 2 squares, 2 per group.

Lesson Place 2 cotton balls into the neck of the bottle and rubber band the hose squares around the nozzle (later, this will slow the drainage and represent rainfall). Place 2 cotton balls into the neck of the bottle and rubber band the hose squares around the nozzle (later, this will slow the drainage and represent rainfall). Add 1 cup of soil to represent ground. Add 1 cup of soil to represent ground.

Lesson Add modeling clay disk to the model. Clay should be cut 5 in diameter. Press the clay to the sides of the bottle to form a seal. Add modeling clay disk to the model. Clay should be cut 5 in diameter. Press the clay to the sides of the bottle to form a seal. Add precut plastic circle to model to form a liner (5 diameter). Add precut plastic circle to model to form a liner (5 diameter).

Lesson Add 1 cup of gravel. Add 1 cup of gravel. Add plastic drinking straw, used to represent pipes for collection and treatment of leachate. Add plastic drinking straw, used to represent pipes for collection and treatment of leachate.

Lesson Add 5 diameter, precut, circle of material representing geotextile fabric. Add 5 diameter, precut, circle of material representing geotextile fabric. Add a layer of soil to the model. Add a layer of soil to the model.

Lesson Add shredded paper to the model to represent MSW. Add shredded paper to the model to represent MSW. Add a final layer of soil to the model to represent daily cover. Add a final layer of soil to the model to represent daily cover. Place top of bottle upside down in bottle. Place top of bottle upside down in bottle. Using the measuring cup, pour water into the landfill model, through the upside down lid (this will emulate rain). Using the measuring cup, pour water into the landfill model, through the upside down lid (this will emulate rain).

Questions to Answer How does this model show us how leachate flows through a landfill? How does this model show us how leachate flows through a landfill? What are the benefits of using a sanitary landfill? What are the benefits of using a sanitary landfill? What are your general thoughts on the differences between the sanitary landfill and the old style landfill? What are your general thoughts on the differences between the sanitary landfill and the old style landfill?

Questions to Answer Why is it important to prevent leachate from getting into the groundwater? Why is it important to prevent leachate from getting into the groundwater? What types of substances could leach into the groundwater from a landfill? What types of substances could leach into the groundwater from a landfill? How has the technology of the sanitary landfill impacted society? How has the technology of the sanitary landfill impacted society?