Field Biology Packet
Unit 5
Soils # 10
INTRODUCTION TO
LANDFILLS
What is a Landfill?
Identify history of garbage and landfills with text books
Directions: Using text book pages 305-307, answer the following questions in complete sentences.
1) What were the first cities to use a garbage dump? How far did the dump need to be from the city?
2) Why did NYC and other cities stop dumping garbage into the ocean?
3) What is a landfill and how much of today’s garbage is dumped in it?
4) Why was open dumping of garbage stopped?
5) Open dumping of garbage is illegal in many states due to leaching of pollutants, what does this
mean?
6) Describe a sanitary landfill.
7) \How does methane gas pose a problem to landfills?
8) What can be done to prevent a methane gas build up?
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BACKGROUND INFORMATION
Most people use the words landfill and dump
interchangeably. However a landfill is not a dump. A
dump is an open hole in the ground where trash is
buried. A landfill is a carefully designed structure
in which trash is disposed and isolated from air
and water. There are many types of landfills that
handle specific types of waste and that are
constructed in unique ways to accommodate that type
of waste.
Before a landfill can be built, much must be taken into consideration. First, a site must be selected
that has an adequate amount of land available. The actual landfill will occupy only a small area of
the site. The rest of the land includes areas for runoff collection, leachate collection, drop-off
areas for vehicles, and buffer zones. Second, the land must be inspected for its composition and
possible impact on groundwater. The rocks should be as watertight as possible to prevent any
leakage from reaching groundwater. Also wells and pipes must be able to penetrate the rock/soil;
therefore the land must be able to accommodate this. Third, nearby waterways should be
examined to determine if runoff from the landfill will potentially reach these waterways. Issues
like the slope of the land toward waterways and distance toward the waterway must be
considered. Finally the impact that the landfill will have on wildlife must also be considered.
The construction of a landfill is also a complicated process. To avoid environmental problems,
many preventive steps are taken during construction. One such measure is a liner. The liner
separates the trash from the groundwater, so as not to contaminate the groundwater. Another
measure is storm water drainage system which collects rainwater that falls on the landfill and
runs off. A leachate collection system is another measure that collects liquid that has percolated
through the landfill. Leachate can contain biological and chemical contaminants, and therefore
cannot enter the groundwater; so, it is collected in a pipe and carried to outside the landfill where
it can be stored and treated. Another measure is a methane collection system. As trash breaks
down, methane gas is released. To prevent an explosion, methane gas must be vented to the
outside of the landfill. A final measure to be taken is a cap which seals the top of the landfill after
the landfill is full.
OBJECTIVE
Students will be able to identify the parts of a landfill and explain how a landfill
MATERIALS
Textbook and guide questions
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PROCEDURE
1. Answer the following questions after reading the Background Information:
A. Why don’t we use dumps instead of landfills for the disposal of trash?
B. What kinds of concerns are created if a landfill is constructed on a fault line (where
earthquakes can occur)?
C. Why is a landfill designed with storm water drainage areas?
d. Why are there usually concerns from nearby residents when a landfill is proposed?
E. After a landfill is full, we cap it and then make use of the land. What kinds of
activities do you believe should be allowed to occur on this piece of land? Justify your
answer. What kinds of activities do you believe should not be allowed? Explain.
ANALYSIS
1. Why is clay placed at the bottom of a landfill?
2. What property of sand makes it a good type of soil to place below trash and above clay?
3. The rate at which we fill landfills is of great concern. How can we slow the rate at which
landfills are filled?
4. Every day the trash in a landfill must be covered, with up to 6 inches of compacted soil.
Why is this a problem?
5. When a landfill is filled and closed a new landfill must be located for waste disposal. Why
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is location becoming more difficult?
6. You have bought a 6-pack of soda, just like the one to the
right. Instead of throwing away the empty cans and plastic
rings when you are finished, you need to reuse all the parts
in your home, school, or work. What would you do with
each can and the plastic rings so that they don’t end up in a
landfill? (You cannot recycle.)
Item
Can 1
Can 2
Can 3
Can 4
Can 5
Can 6
Plastic rings
What the item will be used for?
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REVIEW
1) Identify two problems with using landfills.
2) How much garbage can you save?]

Identify 2 ways you can reduce the amount of garbage you make.
a)________________________________________________
b)________________________________________________

Identify 2 ways you can reduce the impact of the garbage you make.
a)___________________________________________________________________________
b)___________________________________________________________________________

How will this impact the environment?
3) Hypothesize what will happen to the number of landfills in the next 100 years.
4) Hypothesize what will happen to the available land in the next 100 years.
5. Hypothesize what will happen to the number of landfills over the next 100 years, if we recycle
ALL paper goods, plastics and metals; we do not create any new paper goods, plastics or metals;
we compost our organic materials, and only put animal by products and non recyclable materials
into the garbage.
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