The Incredible, Edible Landfill!

Solid Waste Lesson Plan: The Incredible, Edible Landfill!
(Developed by the York County Solid Waste Authority © 2001) 

Objective
Students will learn about the science and engineering that is part of building and operating a modern sanitary landfill. Landfills must meet strict regulatory guidelines in order to operate. In York County, landfill technology is part of the overall integrated system used to manage garbage.

Students will learn that since we can’t recycle everything and some things don’t burn or can’t be processed at the York County Resource Recovery Center, a landfill plays an important role. Students will understand what a landfill is, what types of waste can be managed in a landfill, how landfills are regulated, and how advances in science and technology now influence how and where landfills are built.

Ages:  4 and up.

Group Size:  Up to 60.

Method
Students are appointed “honorary landfill engineers” for the day (after answering a series of questions qualifying them for the job). In this hands-on activity, students build their own landfills layer by layer to learn the function of each layer and how it helps protect the environment as garbage decomposes. Since students use edible materials to build their landfills, once the landfills pass a final inspection and are “permitted to operate”, students get to eat their work!

Materials
Paper bowls or cups, spoons, napkins, wet wipes, fruit roll-ups, animal crackers, licorice, M&M’s™, sugar wafers, marshmallows, chocolate pudding, smarties™, green cookie sprinkles, garbage bag. All materials provided by the Authority.

Subjects/Skills
Science. Discussion, deduction, following directions, fine motor-skills, real-life application.

Duration
30 minutes to 1 hour (adaptable to grade-appropriate length).

Setting
Indoors or outdoors. Classroom, auditorium or pavilion.

Vocabulary Words
Decomposition, municipal solid waste, leachate, monofill, organic, methane, groundwater, liner, cap, subbase, daily cover.

Background
The York County Solid Waste Authority was established in 1971 by the York County Board of Commissioners to assure the adequate and proper disposal of all municipal solid waste generated in York County. To this end, the Authority uses an INTEGRATED system to manage garbage.

This integrated system emphasizes waste reduction, recycling, reuse, and waste-to-energy (burning waste in an enclosed air pollution-controlled environment to reduce it to a smaller volume of ash, and using the heat from burning garbage to produce steam that drives a turbine-generator to create electricity).

This integrated system also includes using landfill technology to manage waste streams that cannot be recycled or processed at the York County Resource Recovery Center (York County’s waste-to-energy facility).

Like many communities across the country, York County relied for years on a landfill to serve as the primary repository for waste disposal. This landfill, called the York County Sanitary Landfill, is located in Hopewell Township and is owned by the York County Solid Waste Authority.

The landfill ceased operations in December 1997 and was capped and closed in 1998. The Authority retains environmental responsibility for the site and continues to maintain and monitor it.

The landfill was permitted by the Pennsylvania Department of Environmental Resources (now the Pennsylvania Department of Environmental Protection) to accept municipal solid waste in 1974. The landfill operated from November 1974 to December 31, 1997. From 1974 to 1989, the landfill accepted garbage from York County households and commercial establishments.

In 1989, when York County shifted from a reliance on landfilling to an emphasis on recycling and waste-to-energy, only the ash residue from the York County Resource Recovery Center was managed in the landfill.

Since 1989, all household garbage produced in York County has been processed at the resource recovery center. All the ash residue from the resource recovery center is now recycled into an aggregate material used in a variety of construction applications.

Waste that cannot be managed at the resource recovery center includes materials that do not burn (such as large metal items), construction demolition (large quantities of drywall, brick, asphalt shingles, window glass, etc.), wastewater treatment sludge, and some types of manufacturing waste. York County has one privately-owned landfill that accepts these waste streams.

A landfill must comply with strict state regulations in order to be permitted to operate. These regulations guide how a landfill is sited (i.e.: must maintain a certain distance from occupied dwellings and perennial streams), how they must be constructed (using liner and drainage systems), and how they must be operated (ton- per-day limits on waste, hours of operation, traffic impacts, etc.).

Landfills constructed today use science and technology to help protect human health and the environment. The materials used in a landfill are intended to protect the soil and groundwater from the potential impacts of decomposing garbage. Landfills that produce sufficient levels of methane gas (the natural result of decomposition of garbage) can harness that resource to produce energy through co-generation. The privately operated landfill in York County is an example of a landfill that does just that!

There is no one perfect way to manage a community’s garbage. But, by using a combination of waste management methods that minimize reliance on landfilling, York County has developed a system that enables us to achieve a 75.6 percent county-wide recycling rate and preserve our valuable land for future generations.

Procedure
Using the materials provided, a speaker will lead students in the construction of a modern sanitary landfill.

Evaluation Tool
Quiz questions (and answers) will be provided for teacher use. Students will be able to describe the basics of how a landfill works, understand the environmental pros and cons of landfill technology, and the role a landfill plays in an integrated waste management system.

Extensions

  1. Schedule an actual tour of a working landfill. Modern Landfill in York County conducts tours for school groups (Call 717-246-4624 to schedule a visit).
  2. How Fast does Waste Decompose in a Landfill? Materials needed: clear container, dirt or potting soil, garbage, water. Have each student fill a clear container with a few inches of dirt. Add a layer of various types of garbage (paper, food waste, metal, glass, etc.). Over the garbage layer, add an inch of dirt. Continue layering with garbage and dirt until container is full. Be sure the last layer consists of dirt. Set containers on a windowsill that is subjected to sunlight. Add some water every other day to simulate rain. Allow each “landfill” container to “decompose” for a month. Each day, ask students to record their observations about the landfill. Has any of the garbage decomposed? If so, what kind of garbage has begun to break down? Is there any odor? Are there any bugs attracted by the landfill? Has the soil changed in appearance? If so, how? Did results vary from container to container? If so, how? What did students discover about how garbage decomposes in a landfill?

How to Get this Lesson Plan Into Your Classroom
This lesson is available at no cost to any York County school or civic group and is presented by a member of the Authority’s Education Center staff. All materials and handouts associated with this lesson plan are provided by the Authority. Call 717-845-1066 to schedule a presentation of this lesson plan for your class or assembly program.