Chapter 20: Water Pollution

Question 1

Cultural eutrophication cannot be prevented by ____.

Answer 1

harvesting excess weeds

Question 2

Agricultural runoff would be increased if farmers ____.

Answer 2

expanded the use of animal feedlots

Question 3

Heavy metal water pollution includes ____.

Answer 3

lead, mercury, and arsenic

Question 4

The Great Lakes are sensitive to pollution because ____ of the water that enters the lakes is flushed out via the St. Lawrence River.

Answer 4

less than 1%

Question 5

Which type of sewage treatment is properly matched with its process?

Answer 5

advanced-physical and chemical processes

Question 6

In cultural eutrophication, fish die from ____.

Answer 6

depletion of oxygen

Question 7

Which statement about the disadvantages of bottled water is false?

Answer 7

most plastic bottles are recycled

Question 8

About ____ of U.S. lakes, rivers, and coastal waters were deemed unsafe for fishing and swimming in 1977.

Answer 8

two-thirds

Question 9

The oil company responsible for the oil spill of the Valdez was ____.

Answer 9

Exxon

Question 10

Storing drinking water in a reservoir is beneficial because it ____.

Answer 10

allows suspended matter to settle

Question 11

Which potential source of water pollution is a nonpoint source?

Answer 11

logged forest

Question 12

Some Great Lakes fish are unsafe for human consumption because of their mercury content.

Answer 12

true

Question 13

Most lakes and other surface waters can eventually recover from cultural eutrophication if excessive inputs of plant nutrients are stopped.

Answer 13

true

Question 14

Contamination of groundwater by natural and anthropogenic sources of ____ is a global problem that has resulted in hundreds of thousands of premature deaths.

Answer 14

arsenic

Question 15

The ____ River was so polluted that it caught fire several times.

Answer 15

cuyahoga

Question 16

In the sewage treatment process, the purpose of chlorination involves ____.

Answer 16

removing discoloration and killing bacteria

Question 17

The North Pacific Garbage Patch is composed of ____.

Answer 17

small particles of plastic and other solid wastes floating on or just below the ocean’s surface

Question 18

Warm water can hold less dissolved oxygen than cold water. What effect would thermal pollution from a power plant likely have on an ecosystem?

Answer 18

it would make the area less suitable for fish

Question 19

What effect would you expect from a river contaminated with untreated sewage?

Answer 19

depletion of dissolved oxygen

Question 20

There are inexpensive ways to effectively remove most pollutants from contaminated groundwater.

Answer 20

false

Question 21

Dredging and straightening the Mississippi River has increased the river’s flow of nutrients and sediment pollution into the Gulf of Mexico.

Answer 21

true

Question 22

Algal blooms created from excessive agricultural and sewage runoffs are least likely to cause ____.

Answer 22

a decrease in agricultural yields

Question 23

What is the leading cause of water pollution?

Answer 23

agriculture activities

Question 24

Developing countries dump the majority of their untreated sewage directly into freshwater ecosystems.

Answer 24

true

Question 25

In the United States, drinking water quality is primarily regulated under the ____.

Answer 25

Safe Drinking Water Act

Question 26

What percentage of the people using coastal beaches in the United States developed ear infections, sore throats, eye irritations, respiratory disease, or gastrointestinal disease from swimming in seawater contaminated by infectious viruses and bacteria?

Answer 26

25%

Question 27

In testing water along the length of a stream, you notice an oxygen sag curve. What would you expect to find associated with this?

Answer 27

very high dissolved oxygen

Question 28

Parking lots are major sources of point source pollution for rivers and lakes.

Answer 28

false

Question 29

The back-to-the-tap movement advocates ____.

Answer 29

avoiding bottled water

Question 30

Which statement about the Gulf of Mexico’s dead zone is false?

Answer 30

Negative effects from the dead zone are short-term and confined to the immediate area.

Question 31

Lakes and reservoirs undergo little vertical mixing because ____.

Answer 31

they contain stratified layers

Question 32

Though it would be cheaper and more effective to protect watersheds around water sources rather than building treatment facilities, no major city has made the attempt to do so.

Answer 32

false

Question 33

What percentage of expensive bottled water is actually bottled tap water?

Answer 33

more than 40%

Question 34

Which of these is not a cause of cultural eutrophication?

Answer 34

overfishing

Question 35

Oil and gas drilling are the leading causes of water pollution.

Answer 35

false

Question 36

Which statement about lakes is true?

Answer 36

Lakes are more vulnerable than streams to contamination by plant nutrients, and toxic substances.

Question 37

In cities of less-developed countries, stream pollution is often ____.

Answer 37

caused by dumping 80–90% of raw sewage directly into rivers

Question 38

How long does it take for pollutants to be flushed out of the largest of the Great Lakes (Lake Superior) into the ocean?

Answer 38

19 years

Question 39

The Gulf of Mexico’s dead zone is the only such dead zone in the world’s oceans.

Answer 39

false

Question 40

Oxygen sag curves can occur when ____.

Answer 40

bacteria break down biodegradable wastes

Question 41

The natural nutrient enrichment of a shallow lake, estuary, or slow-moving stream is called ____.

Answer 41

eutrophication

Question 42

Besides contaminated drinking water, lead poisoning in the home commonly occurs because of ____.

Answer 42

lead paint

Question 43

Imagine you are testing water samples from a local pond for pollutants. Your lab instructor sees the results of your dissolved oxygen test and remarks that your water sample has the same dissolved oxygen level as water found near the seafloor of a dead zone. What is the dissolved oxygen level of this water sample?

Answer 43

2-3ppm

Question 44

Which organism is least likely to cause disease?

Answer 44

algae

Question 45

Drinking water for about ____% of the United States population and ____% of the rural populations comes from groundwater.

Answer 45

50; 95

Question 46

The Gulf of Mexico’s dead zone is caused by high levels of ____ in the Mississippi River.

Answer 46

plant nutrients

Question 47

You are testing a sample of water from a nearby lake that has very few fish living in it and you suspect that it is the dissolved oxygen level that is responsible for this. What dissolved oxygen level would you associate with a body of water that can support very few fish?

Answer 47

2.3 ppm

Question 48

Placing contaminated water in a clear plastic bottle and exposing it to the sun can kill infectious microbes in as little as three hours.

Answer 48

true

Question 49

Cold temperatures of groundwater slow down the chemical reactions that decompose wastes.

Answer 49

true

Question 50

Dead zones have a detrimental impact on ____.

Answer 50

fish and shellfish populations

Question 51

Oxygen can be depleted from a body of water by ____.

Answer 51

biodegradable wastes

Question 52

The Exxon Valdez oil spill was an example of point source water pollution.

Answer 52

true

Question 53

There are actions that everyone can take to help reduce water pollution. Pollution will not, however, be reduced if we ____.

Answer 53

buy commercially produced foods

Question 54

On a human time scale, nonbiodegradable wastes (such as toxic lead and arsenic) remain in the water permanently.

Answer 54

true

Question 55

It is possible to turn sewer water into pure drinking water.

Answer 55

true

Question 56

For a lab activity, you are testing water samples from your favorite swimming hole. Coliform bacteria colonies were found in the 100 mL samples you used in your test. Is the water still safe for swimming?

Answer 56

Only if there were less than 200 colonies.

Question 57

Arsenic in the drinking water is not a concern in the United States.

Answer 57

false

Question 58

A major water pollution problem is exposure to infectious bacteria, viruses, and parasites.

Answer 58

true

Question 59

The primary cause of BP’s Deepwater Horizon oil spill in the Gulf of Mexico was ____.

Answer 59

faulty equipment and poor decision-making

Question 60

The most effective way to deal with groundwater pollution is to ____.

Answer 60

prevent contamination

Question 61

The most common problem encountered by seabirds coated with oil is ____.

Answer 61

loss of buoyancy and insulation, causing deaths from drowning or loss of body heat

Question 62

In your environmental science lab, you test water samples from local bodies of water and find high levels of coliform bacteria. What does this tell you the water is contaminated with?

Answer 62

animal wastes

Question 63

Wetlands, estuaries, mangrove swamps, and coral reefs are examples of ____.

Answer 63

coastal areas

Question 64

The Clean Water Act could be strengthened by ____.

Answer 64

allowing citizens to bring lawsuits to ensure that water pollution laws are enforced

Question 65

Which source is often responsible for thermal water pollution?

Answer 65

power plants

Question 66

Climate change contributes to water pollution in some areas because of local changes in precipitation.

Answer 66

true

Question 67

Red, brown, and green toxic tides can release waterborne and airborne toxins that poison fish, shellfish, birds, and humans who eat seafood.

Answer 67

TRUE

Question 68

The biggest threat to water quality in the Great Lakes is from ____.

Answer 68

increased runoff caused by urban sprawl

Question 69

Dead zones are characterized by a lack of ____.

Answer 69

oxygen

Question 70

A lake with low nutrient levels and very clear water is called ___.

Answer 70

oligotrophic

Question 71

Most of the oil that pollutes the ocean comes from ____.

Answer 71

urban and industrial runoff from land

Question 72

A good indicator of water quality is a low quantity of ____ present in a water sample.

Answer 72

coliform bacteria

Question 73

Which potential source of water pollution is a point source?

Answer 73

oil wells

Question 74

The Great Lakes Water Quality Agreement between the United States and Canada improved water quality by ____.

Answer 74

upgrading sewage treatment plants

Question 75

Groundwater is primarily stored in underground ____.

Answer 75

aquifiers

Question 76

What percentage of the world’s population lives on or near the coast?

Answer 76

37%

Question 77

The sun’s heat and ultraviolet (UV) rays can kill infectious microbes in water in clear plastic bottles.

Answer 77

true

Question 78

All arsenic pollution in groundwater is human-caused.

Answer 78

false

Question 79

Imagine you are testing water samples from a local pond for pollutants. You measure the dissolved oxygen level at 20 degrees Celsius and find evidence that the pond is slightly polluted. Which of these dissolved oxygen levels would be expected of slightly polluted water?

Answer 79

7.2ppm

Question 80

The Great Lakes possess ____% of all the surface fresh water in the United States.

Answer 80

95