module41REVIEW

490

In this module, we learned that wastewater from livestock and humans can cause harmful effects on the water bodies that receive it. Some of the most important effects are the high oxygen demand associated with the decomposition of the organic matter that can cause dead zones, the production of inorganic nutrients such as nitrogen and phosphorus that can cause algal blooms, and the introduction of disease-causing organisms. Fortunately, humans have invented several technologies to handle wastewater including septic tanks, sewage treatment plants, and manure lagoons. These technologies rely in part on decomposition of organic matter and help reduce the presence of pathogens. In some cases, they also reduce the amount of inorganic nutrients before the wastewater is dumped into a natural water body. In the next module, we will examine how a number of heavy metals and other chemicals affect aquatic ecosystems.

Module 41 AP® Review Questions

Question 1

1. Which is a point source of pollution?

  1. Farm runoff

  2. A sewage treatment plant

  3. Storm runoff

  4. A suburban community

  5. A harbor

Question 2

2. Eutrophication

  1. is the result of excess carbon.

  2. causes low BOD.

  3. can cause dead zones.

  4. is rarely caused by human activities.

  5. only occurs in fresh water.

Question 3

3. Fecal coliform bacteria

  1. is used as an indicator of water quality.

  2. is the cause of many waterborne diseases.

  3. is another name for Cryptosporidium.

  4. usually causes diarrhea.

  5. is rarely found in septage.

Question 4

4. Leach fields are

  1. used to remove sludge.

  2. part of tertiary water treatment.

  3. used to filter septage.

  4. a result of sewage dumping.

  5. often used with manure lagoons.

Question 5

5. A manure lagoon is being built for a dairy with 700 cows, each of which produces 40 L of manure each day. How large must the lagoon be to hold 30 days’ worth of manure?

  1. 21,000 L

  2. 28,000 L

  3. 120,000 L

  4. 560,000 L

  5. 840,000 L