1. In the United States, the majority of water pollution of streams and lakes is from:
Point pollution from sewage treatment plants
Point pollution from abandoned mines
Point pollution from factories
Nonpoint pollution from agriculture

2. Which of the following is not listed as a major category of water pollution?
Plastics
Erosion
Acid deposition
Heat

3. True or false? Flooding tends to produce cleaner drinking water by flushing rivers and streams of debris and pollutants.
True
False

4. The oxygen sag curve is caused by:
Inorganic wastes
Oxygen-demanding wastes
Sediments
Plant nutrients

5. Cultural eutrophication of lakes is most often caused by input of:
Nitrates and phosphates
Selenium
PCBs
Sediment

6. True or false? Since 1972, algal blooms in the Great Lakes have decreased.

7. Groundwater cannot cleanse itself of degradable wastes quickly because of all but which one of the following reasons?
It has a high concentration of dissolved oxygen
It flows slowly
It has small populations of decomposing bacteria
Cold temperatures slow down decomposing chemical reactions

8. Which of the following is a major groundwater pollutant in parts of India and Bangladesh?
Fluoride
Arsenic
Selenium
PCBs

9. By weight, the bulk of the phosphates in Chesapeake Bay comes from:
Air pollution
Shellfish farms
Pesticide runoff
Sewage treatment plants

10. Secondary sewage treatment:
Removes about 60% of suspended solids from sewage
Does not remove any phosphorous or nitrogen from sewage
Utilizes aerobic bacteria
Is a mechanical process

11. About _____% of sewage sludge is dumped in conventional landfills.45 35 55 65

12. Using _____ would reduce the amount of sewage output from homes and businesses.
Tertiary sewage treatment
Composting toilet systems
Sludge digesters
Anaerobic digesters

13. Scientists call for a ban on _____ in all new plumbing.
Copper
Selenium
PVC
Lead

14. True or false? Bottled water is always of better quality than water from municipal water suppliers.

15. True or false? The Cuyahoga River in Ohio was so polluted it actually caught fire twice (in 1959 and 1969).
True
False

16. Viruses Shistosomiasis Fecal coliform Cholera
_____ are bacteria that live in the colons and digestive tracts of humans and other animals and are often present in unsafe amounts in freshwaters.
Viruses
Shistosomiasis
Fecal coliform
Cholera

17. True or false? Pollution of coastal areas is largely insignificant due to the large dilution effects of ocean waters.
True
False