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Students devise ways to clean up an oil “spill.”
Academic Areas: | Science |
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Grade Levels: | Grades 4–8 |
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Learning Objectives: |
After participating in the activity that follows, students will be able to do the following:
- List several ways of cleaning up oil spills.
- Name the biggest cause of oil contamination.
- Analyze experiment results to find a “best” way to deal with oil spills.
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Science Standards Met: |
- Gains abilities necessary to do scientific inquiry
- Learns properties and changes of properties in matter
- Aquires understanding about science and technology
- Knows about natural hazards
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Materials for each team of three or four students: |
Newspapers, water, clear glass or plastic bowl, 2 tablespoons of vegetable oil, paper or plastic cup, paper towels, cotton balls, Styrofoam pieces (such as packing material), string, index cards, tape, dish detergent, sawdust, diatomous earth (available at garden-supply stores), sand, gauze cloth, notebook, and pen
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Background:
The phrase “oil spill” is likely to bring to mind a huge tanker wreck, such as the Exxon Valdez, that dumps thousands of gallons of oil into the sea. Such spills are catastrophic but, surprisingly, they are not the greatest source of oil contamination in the ocean. Research conducted by the state of Alaska found that more than 1 billion gallons of oil—100 times as much as the Exxon Valdez spill—dump into the ocean every year. The majority of this contamination comes not from tanker spills, but rather from wastes and storm sewer runoff. In other words, the oil that people throw out or dump down the drain constitutes the largest source of oil in the seas.
The best way to protect the ocean is to prevent oil from getting into the water. Requiring double hulls on tankers and educating people not to dump oil but to recycle it instead are two ways. But despite prevention, spills still occur and cleaning them up remains a challenge for scientists and conservationists.
Each spill is unique, as various types of oils create different cleanup challenges. Generally, spills are contained as well as possible to prevent the oil from contaminating more water or shoreline. Various floating and submerged barriers help contain a spill. Then oil removal can begin. This process may involve using sorbent materials such as peat moss, straw, sawdust, clay, or types of plastics that absorb the oil. Sometimes the oil is simply dispersed using surfactants that break the oil into tiny droplets. The oil isn’t physically removed from the water, but because it is broken down into such tiny amounts, the natural action of wind and waves helps eliminate it—hopefully before it can reach shore. There are also chemicals that turn the oil into a jelly-like substance that can then be more easily scooped up.
Oil is just one type of pollutant that harms oceans, but it is a difficult one to remedy. Your students will realize this when they attempt to clean up an oil “spill” in the classroom.
What to Do: |
- Cover the work surface with newspapers. Then fill the bowl about half way with water. Pour 2 tablespoons of vegetable oil into the water.
- Explain to your students that they are going to be in charge of cleaning up this oil “spill.” Their job is to contain and clean up the spill using the materials given to them and they must find the best way to remove the oil. Each team should make notes about the methods tried and the results.
- First, the students should try to contain the spill. Pieces of string or index cards taped together and to the sides of the bowl are a couple of ways to keep the oil from spreading. Once students have the spill contained in still water, try “making some waves” with your finger to see how well the containment works in “choppy” seas.
- Next, students can begin testing various materials to see which ones disperse, absorb, or remove the oil best. Remind students to test the methods in both still and choppy conditions. Here are some ways to use the materials provided:
- Gauze cloth—Use as a “net” to trap and remove the oil.
- Paper towels, cotton balls, Styrofoam, saw dust, diatomous earth—Place on top of the oil, let sit for a bit, and then remove to observe the results.
- Dish detergent—Pour small amounts onto the oil to disperse it.
- Sand—Pour onto the oil, and observe what happens.
- Rate the effectiveness of each method. Students may find that a combination of methods works best. After assessing the results, each group should share its findings with the class. Try to reach a consensus on which method works better under calm conditions and which is better in choppy waters.
- Ask the class what is responsible for most of the oil that ends up in the ocean. Use the information in the background section to explain that individuals, not oil tankers, are the biggest culprits in releasing oil into the seas. Discuss ways to prevent oil contamination.
- As an extension, students can do additional research into actual methods of oil spill cleanup. Do cleanup technicians use methods similar to those the students tried? What are some major oil spills of the past and how were they cleaned up? What new methods for oil cleanup are being studied by scientists?
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Resources
After the Spill: The Exxon Valdez Disaster, Then and Now by Sandra Markle (Walker, 1999).
The EPA Oil Spill home page provides information about oil spills, including techniques for responding to spills.
NASA Quest Oil and Water presents“Oil and Water Don’t Mix…or Do They?” This activity expands on the one detailed above by investigating how oil affects wildlife. Students use feathers and synthetic fur to learn about how oil affects animals and what methods best clean feathers and fur.
Oil Spill, available from the NSTA Science Store, is an oceanography module containing reading, writing, and hands-on activities.
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Listen to More?
Click on these links to hear more about oil contamination and ways to prevent and clean up oil spills.
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![No Minor Spills [5/25/00]](images/audio.gif){kind=small}