Building an Aquifer
Background - An aquifer is an area below ground in which water is stored between the grains of sand and rock. We will be building a model of two types of aquifers. You should work in groups of about 5 students.
Materials – Each group will need.
1 jar, sand, gravel, two straws, a squirt bottle, clay, food coloring, a piece of green felt –(to represent grass), cocoa powder (to represent pesticide), scissors, tape, and water.
Procedure –
1) The straws will represent the wells that have been dug into the artesian aquifers. Because we will not be able to drill into our aquifer after we build it we will put the wells in first. Tape both straws to the side of your jar. The wells should be about .5- 1 cm from the bottom of the jar and should be about 1 cm apart from each other.
2) Put enough gravel in the jar to fill it up about 4 cm.
3) Now put enough water in the jar to just barely cover the gravel.
4) Flatten out the clay and place it over the gravel, sealing the confined aquifer.
5) Now put the sand in the jar. Form it into a hill on one side of the jar. The hill should be about 4 cm tall and the lower part about 1 cm tall.
6) Put enough water in the jar to make a small “lake” in the lower part of the sand and leave the higher part out of the water.
7) Now cut the felt to fit on the hill. This will be grass on your hill. – Answer question #1
8) There are young children playing by your lake, but mosquitoes are biting them. The parents in the community are concerned about West Nile virus. Put enough “pesticide” on the grass to kill the mosquitoes.
9) One of your wells has been polluted by chemicals. Put about 7-8 drops of food coloring in one well to represent the pollution.
10) Use the squirt bottle to make it rain on the grass and pond.
(answer # 2+3)
11) Open the squirt bottle and use it as a pump to pull water out of the clean well. Observe the pollution from the other well. If you pull up enough water what happens to the clean well? (answer 4+5)
Name______Date______
People in your group ______
Observation Questions
1) Describe the appearance of the water in both aquifers. ______
2) Describe what happened to the water table aquifer and to the lake when you made it rain.
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3) If there were fish in your lake, how might they be affected by the pesticide now that it has rained. If you know anything about bioaccumulation include this concept in your answer.
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4) What happened to the pollution as you pumped up the clean water?
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5) In the 1970’s laws were passed that made it illegal to put garbage and chemicals down old wells. Before the 1970’s people used old wells as land fills or garbage disposal places so many of these people were upset about the law because they felt, “It is my well I can do what I want to it. I am only hurting my own property.” Why is this sentiment not really correct?
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6) Lately there has been a push to limit the use of pesticides, herbicides, and fertilizers. Why do you think this is an issue?
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7) On Long Island, NY people get their water from an unconfined aquifer. Most people have septic tanks. This is a tank in which all the waste water (shower, sinks, toilets, washers) from their house goes into. It is under ground and the waste slowly seeps out of the tank into the ground. Why should the people who live there be concerned about their water quality?
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8) There is a law that went into effect in 2008 that requires all new underground fuel storage tank to have a secondary containment system (double tanks) In other words they must have two layers of metal not just one. Why do you think this law was put into place? (
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9) According to the law mentioned in question 8, a secondary containment system is required on all underground storage tanks installed on or after July1, 2008. The law does not apply to undergroundstorage tanks existing at a facility before July 1, 2008. This is often called “grandfathering in” an old system. Do you think old facilities should be grandfathered? What if they can’t afford to change their tanks and will go out of business if they are made to dig up the old tanks and replace them?Explain your answer.
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10) Methyl tertiary butyl ether (MTBE) is a natural gas derivative used as a gasoline additive to help reduce smog. Later it was found out that MTBE does not break down in water. It does not get cleaned out of water when the water goes through the cleaning process so it can be pumped to our house. Federal research studies have linked MTBE to tumors in laboratory rats. Imagine you are an employee of the EPA. How would you weigh the benefits of reduced smog with the dangers of MTBE? Describe tour thought process and the decision you would implement.
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Going Further. Choose one of the topics below and research this topic. Write a 1-2 page summary of what you learned. Be prepared to share what you learned with a small group.
MTBE in Nevada
The history of the Sparks Marina
PCE contamination of ground water in Washoe County
Overuse of ground water