The assessment tasks presented below are designed to be used to: 1) elicit students' prior ideas, 2) engage students in thinking about water quality issues, and/or 3) assess students' understandings following instruction.  Assessment Task 1 reflects an assessment task with several possible correct answer where students construct a rational for their response.  Assessment Tasks 2 and 3 are practical tasks where student perform water quality tests to answer the questions.  Assessment Task 4 is an open-response task where students must decide where to place a well based on runoff.

Tom, Joe and Mary, fifth-grade students in Ms. Well’s classroom, were discussing the results of their drinking water tests.  Their water sample was taken from the well on Mary’s parent’s farm.  All of the tests were within the acceptable EPA range except for Nitrate. The Nitrate reading was 12 PPM.  The EPA recommends that Nitrate levels be less than 10 PPM.  The well is located 150 feet from the septic system, 200 feet from the corn field, 100 feet from the county road, and 200 feet from the hog feed lot.  In determining the cause of the high Nitrate level, Mary believes it is because the well is close to the cornfield and Nitrate from corn fertilizer is leeching into the ground water that flows into the well.  Although Tom respects Mary’s idea, he disagrees.  Tom thinks that the source of the Nitrate is the hog feed lot.  Waste products from the hogs are percolating through the ground after a rainstorm and into the ground water that flows into the well.  Joe, however, thinks the high Nitrate is caused by the road salt used in the winter, that runs off the road and leeches into the ground water that flows into the well.  Which student, Tom, Joe, or Mary, do you think has the better explanation for the cause of the high Nitrate level and why?

You are the lab technician for the Department of Water Quality for the State.  You have received three water samples, one from each of the three wells for the City of Water Valley.  The Engineer for Water Valley would like you to test each sample for Total Hardness (total amount of calcium and magnesium dissolved in the water).  The Engineer wants to make sure that the water in each well is within the EPA range of 50 to 125 PPM, and whether the City needs to treat the water for hardness or softness.  It is known that soft water (Total Hardness < 50 PPM) can damage cooper plumbing and the lead solder used in the joints.  Hard water (Total Hardness > 250 PPM) can also damage plumbing by forming scale inside pipes.  Hard water also forms scale on the surface of sinks and tubs and reduces the formation of suds from soap.  As the technician, you need to test the three water samples (Well 1, Well 2, and Well 3) and write a brief report stating your findings and recommendation to the Water Valley Engineer.

You work in the home appliance department of the local department store.  Mrs. Johnson has brought in a water sample to test for Total Hardness (total amount of calcium and magnesium dissolved in the water) and Iron to see if she needs to purchase a water softener.  You know that the EPA range for Total Hardness is between 50 and 125 PPM.  You also known that soft water (Total Hardness < 50 PPM) can damage cooper plumbing and the lead solder used in the joints, and that Hard water (Total Hardness > 250 PPM) can damage plumbing by forming scale inside pipes.  Hard water also forms scale on the surface of sinks and tubs and reduces the formation of suds from soap, making cleaning more difficult.  High Iron concentrations (> 0.3 PPM), although causes no health risk, does create an unpleasant taste and can stain laundry, sinks, and tubes.  As the clerk, you need to test Mrs. Johnson’s water sample and complete the Customer Report below, recommending whether she needs to purchase the $500 water softener.
 

Customer Report

Customer Name: _____________________________  Date: __________

Water Test Results                                                          Recommendation
 
 
 

Clerk Name: ______________________________________
 

You are the Water Quality Engineer for Water Valley and the two new homes on Thomas Avenue have asked you to recommend the best location on their property to drill their water wells.  The location should reduce the risk of well water contamination from storm runoff.  You have conducted a site visit identifying the direction of possible water runoff from storms (arrows on site map).  Indicate on the map the site you would recommend that each landowner drill their well.  You also need to provide a written report that explains the reasons behind your recommendation.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

From Home*A*Syst, D.J. Eagan (1997), Editor