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Hydrofracking Data

Unit Plan: Hydrofracking - with Chloride DataLesson: 2 Time: One-two 40-minute class periods Setting: Classroom
6-8, 9-12Data Exploration & NOS
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Students will know how to recognize variability in hydrofracking data, and will be able to make an appropriate graph of a selected variable in Excel or by hand. 


    Students explore the idea of groundwater and pollution with visuals/models.

    Students explore the reasons for variability with a short hands-on activity. 

    Students graph hydrofracking data and discuss ecological implications. 


    • Copies of student worksheet – Hydrofracking Data
    • Copies of forest data (Excel or handout)
    • Jar with water
    • Salt
    • Conductivity or chloride meter
    • Plastic bags filled with two different colors of beans (enough bags for each pair of students to have one)
    • 10 leaves from the same tree (or 10 pine needles, pine cones, blades of grass, etc)
    • Computer or overhead projector.
    • Beans Example Template (Excel datasheet)
    • Sampling bottles

    Advance preparation: Prepare a bag for each pair (or group) of students that has two different colors of dried beans (any two colors will work).  You want to have enough beans in the bag so that students need to take the beans out of the bags and carefully count them.  We suggest bags of 40-50 beans per color.  Each bag needs to have the same amount of beans- but don’t tell the students this!   You will limit the amount of time it takes them to count the beans, and providing a distraction while they are counting can also be helpful.  We suggest giving students 1 minute to count if you use 50 beans per color.  This reminds students how easy it is to make mistakes when you aren’t paying close attention!  For a fun introduction to this idea, consider watching the “Gorilla in the Room” video: .  This video shows two teams of students (team white vs team black) passing basketballs.  Students are asked to count how many times the white team passes their ball.  Most students will completely miss the gorilla that walks into the middle of the basketball court during the 1-minute exercise. 

    1. Engage:  Since students struggle with visualizing how groundwater contamination (and groundwater) works, this engagement is designed to improve their understanding of this type of water movement.  There are several suggestions for engaging students to think about groundwawter:
    • Create a simple groundwater model by following the plans on this website:
    • There is also a good visualization online through the MetEd website: .  You have to create an account, but it is free.  Once on their website, look for the module titled “Understanding the Hydrological Cycle”.  Within that module, there is a section on Groundwater that students can go through on their own time. 
    • We highly recommend the MetEd module on “Watersheds”, which has a section on Water Quality that explains how contaminants move into groundwater.
    • You can do a simple demonstration of water movement through “soil” – add food coloring to a small clear cup of dried rice.  Students can see how the liquid moves.  I also like this groundwater pollution demo:
    1. Explore: Hand out the student worksheet, “Hydrofracking Data” along with the forest data (either in Excel or as a handout).  Each variable has been provided on a separate page, or on a separate tab in Excel.  Once students have produced the graph, begin a discussion of variability.  This study was conducted by the USFS over the course of three years; the citation for the full report is found in the Credits. 
    2. To introduce the concept of variability, give each pair (or group) of students a bag of beans.  Give students a defined amount of time (less time if you have fewer beans – I recommend limiting the counting to 1 minute if you have 50 beans per bag) and ask them to count all of the beans in the bags.  Tell them that both speed AND accuracy matter.  Once students have counted, they should come up to the board and write down their counts on the board.  Don’t allow students to recount their beans.
    3. Compare and discuss the students’ results – are they the same?  Do some counts differ?  Why?  What are some reasons for the differences – could it be due to human error, or actual differences between the bags?
    4. Next, provide students with the natural objects – leaves, pine needles, etc.  They should have enough of the objects so that when they compare them, they are similar but not exactly the same.  Ask students to measure the diameter of the leaves or the lengths of the pine needles, and record the results.  Students should share their results.  Ask:  Why are there differences between the leaves?  Are these differences due to the leaves, or to human error?  Brainstorm answers to both questions. 
    5. Explain: Place this chart up on the board, and fill in with student help (students have a copy of this chart in their packet).  Ask students to think about potential error with reference to the Baltimore salt data.   Some examples are included below.


    Real/natural – what might be some sources of variability that are due to the ecosystem? 

    Human/experimental – variability due to human error, sampling effort, design etc

    • Sampling during different times of year might provide different results
    • Rainfall events could affect results
    • The soil might have had elevated levels of some of the variables to begin with
    • Interactions between components of the ecosystem might affect results


    • The sampling equipment might have been different throughout the year
    • Researchers may have collected data in different areas
    • Data might not have been collected often enough
    • The sampling equipment might have been working incorrectly or someone used the equipment incorrectly 

     Students often focus on human error instead of thinking about the types of changes that might naturally occur in the ecosystem.  Make sure they can also recognize some natural variability in the system.  Finally, show students the “Beans Example Template” that gives an example of the bean data – this spreadsheet will show you an example of the activity.  (You can also put in your own bean count data.)  First, you can see the bean counts individually (as a scatter plot), the averaged bean counts (bar graph), and a bar graph with error bars.  Ask students to explain the benefits and drawbacks of the different types of graphs.  Students should recognize that error bars allows them to have some information about the range of the data in the sample, similar to a scatter plot, but with the additional benefit of knowing the average of the set of data.  This idea will be reviewed in the last lesson.

    1. Explain: Ask students to graph their chosen variable.  Then, lead a discussion about which variable showed the largest change as a result of the flowback water application.  Depending on your class, you can have students share their results in small groups or in a large discussion format.  Students should notice that chloride levels changed dramatically, and rapidly, immediately after the application.  But, there are many other chemicals that the scientists did not measure. The chemicals found in the flowback water include naturally occurring materials that were in the ground, along with chemicals that were added to the water in order to do the fracking. 
    2. Scientists are concerned that if proper safeguards are not put into place, and the number of wells continues to increase, it could have a significant impact on streams.  The table below provides information on the types of materials in the wastewater (for more details, please see Issues 7& 8 of the Marcellus Papers - 




    1. Extend: Students could research the ecological impacts of the compounds found in flowback water on other organisms.  


    1. Evaluate: Students should complete the worksheet.  Pay attention to whether students are able to explain their claim about whether a change in soil chemistry will affect the aquatic ecosystem.   For homework, have students bring in a water sample to test it for conductivity and/or chloride. 




    Lesson Files

    Student Worksheet
    Beans Example Excel Template
    Chloride Data Sets Excel
    Chloride Data Excel Answers
    Worksheet Answer Key
    Chloride Data Sets Handout

    Benchmarks for Science Literacy

    2B Mathematics, Science and Technology, 2C Mathematical Inquiry, 8C Energy Sources and Use

    NYS Standards

    MST 1 - Mathematical analysis, scientific inquiry, and engineering design, MST 3- Mathematics in real-world settings
    Next Generation Science Standards

    Science and Engineering Practices

    Analyzing and interpreting data, Using mathematics and computational thinking

    Adams, M.B., Edwards, P.J., Ford, W.M., Johnson, J.B., Schuler, T.M., Thomas-Van Gundy, M., and F. Wood.  2011.  Effects of Development of a Natural Gas Well and Associated Pipeline on the Natural and Scientific Resources of the Fernow Experimental Forest.  General Technical Report NRS-76.