Lab 7 - Water Contamination
Sonahana
Lab7_guideline.pdf
EAS104 Lab 7 - Water Contamination
Fall 2019
In this Lab, you will test a variety of water samples. Then you will determine how to treat the water samples to make them safe to drink.
Procedure:
1. Go to http://www.glencoe.com/sites/common_assets/science/virtual_labs/CT04/CT04.html
2. Click the right and left arrows to select a body of water to analyze. 3. Click Test to test the water sample. 4. Look at the results of the water analysis to identify which contaminants exceed the safe
range. 5. Click the tabs to find information on how to treat each contaminant. 6. Enter the contaminant and treatment information in the Table. 7. Click Go To Treatment to go to the treatment screen. 8. Use the information in the Table and click the wheels on the valves to add chemicals or
additives to the water sample. 9. Click the Treatment Switch to start treating the water. The Safe/Unsafe Sign will indicate
whether the water is safe to drink. 10. If the water is safe to drink, use Return to Lab to go to the lab screen and test another
water sample. 11. If the water is unsafe to drink, check your information and treat the water sample again. 12. When you have tested and treated all the water samples, use your completed Table to
complete the Journal questions.
Questions:
1. Fill in the table below based on your water sample results (35 points).
Water Sample Acidity pH
Metals Coliform bacteria
Pesticides/ Herbicides
Nitrate Level
Type of Contamination
Treatment
Safe Range 6.5 - 8.5 < 1.3 mg/L
0 per 100 mL
< 0.04 mg/L
< 10 mg/L ----------------- ---------------
City
Lake
Mountain
Rural
Well
2. What contaminants were found in the surface water (which can be exposed to air) samples? (2 points)
3. What contaminants were found in the groundwater (typically used for residents’ supply, e.g. city, rural and well) samples? (4 points)
4. Generally, farmers do not farm and industries do not build factories on the sides of mountains in remote wilderness areas. These areas are usually not highly populated by people. What might explain the high nitrate level in the mountain water in this activity? (1 point)
5. What is pH level, what are its characteristics, and how does it contribute to pollution? (3 points)
6. What chemicals are used in treating low pH levels?(1 point) 7. Which regions of the city are supplied by surface water before 2007? Which regions of
the city are supplied by groundwater before 2007? What about current water distribution? (3 points) https://www1.nyc.gov/site/dep/water/groundwater-supply-system.page https://www1.nyc.gov/site/dep/water/current-water-distribution.page
8. Water in an old building, tested recently, showed high copper and iron content, and low pH levels. A water reading has taken 20 years before showed low pH levels. None of the new buildings on the same street showed signs of metallic contaminants.
a. What do you expect from the water reading (e.g. pH level) in the new buildings? (1 point)
b. What can be the reasons for low pH in water samples from the new buildings? (1 point) https://www1.nyc.gov/site/dep/water/monitoring-for-lead.page
c. What can you do to reduce your exposure to lead in drinking water? (3 points) https://www1.nyc.gov/site/dep/water/monitoring-for-lead.page
