Deck 16: Groundwater

Question 1

Agriculture is the primary user of groundwater in the United States.

Answer 1

True

Question 2

Groundwater supply demands have resulted in increased pollution but no lack of supply.

Answer 2

False

Question 3

The majority of Earth's usable fresh water comes from lakes, rivers and streams.

Answer 3

False

Question 4

Porosity of igneous rocks is generally less than that of sedimentary rocks.

Question 5

If rocks are porous rocks, then they are permeable also.

Question 6

The water in a well drilled into an unconfined aquifer will rise to the elevation of the water table.

Question 7

The water in an artesian well drilled into a confined aquifer will rise in the well above the elevation at which it was first encountered.

Question 8

The water table is flat, featureless surface between the zones of aeration and saturation.

Question 9

Water may move upward, against the force of gravity.

Question 10

A spring forms where water under pressure "spring"up or shoots from the ground.

Question 11

As long as limestone is present near the surface, karst topography will form in any climate.

Question 12

Geysers are hot springs formed where the temperature of the water is above boiling point.

Question 13

Once an aquifer has been contaminated it "cleanses itself"rather rapidly because the contaminants adhere to rock/sediment particles.

Question 14

Groundwater contamination is relatively easy to trace to its source and to contain.

Question 15

The major source of groundwater is

A) water infiltrating from lakes and streams
B) precipitation that infiltrates the ground
C) recharge ponds
D) wastewater-treatment systems

Question 16

Which of the following would be considered groundwater?

A) water infiltrating from lakes and streams
B) water infiltrating from precipitation
C) water infiltrating from septic systems
D) water infiltrating from the base of glaciers
E) all of the above

Question 17

Which of the following is most porous?

A) shale
B) siltstone
C) gravel
D) granite
E) limestone

Question 18

Which of the following is most permeable?

A) shale
B) siltstone
C) arkose
D) limestone
E) quartzite

Question 19

Within the zone of saturation, water always moves

A) under the influence of gravity
B) from high topographic positions to low topographic positions
C) from areas of high pressure to areas of low pressure
D) A and B
E) all of the above

Question 20

Springs occur where

A) streams have cut valleys below the regional water table
B) where an impermeable layer intersects the surface
C) where a perched water table intersects the surface
D) seepage occurs at the surface
E) all of the above.

Question 21

Conditions needed for the development of karst topography include

A) humid climate.
B) arid climate.
C) carbonate bedrock at a shallow depth.
D) A and C
E) all of the above

Question 22

The water table is lowered when

A) discharge is less than recharge
B) drought occurs
C) water quality decreases
D) soil moisture is evaporated
E) A and D

Question 23

Recharge of groundwater is affected by

A) climate change
B) seasonality of climate
C) land use and cover
D) pathways of groundwater movement
E) all of the above

Question 24

Current production of groundwater from the High Plains Aquifer cannot be sustained because

A) the small farmer is increasingly not viable
B) recharge is less than discharge
C) discharge is less than recharge
D) global climate is warming because of human impacts
E) irrigation will decrease in the future

Question 25

One of the reasons that geothermal energy is not as widely used as it could be because

A) geothermal waters are not common
B) it is not cost-effective
C) geothermal water is too hot to handle
D) it has high greenhouse gas emissions
E) it is not inexhaustible

Question 26

In regions of moderate to high rainfall the groundwater table is the same as the level of water in___________and___________ .

Question 27

Saltwater incursion occurs because saltwater is (less/more) ___________dense than fresh water, and thus, remains (above/below) ___________fresh water unless discharge pumping exceeds the recharge of fresh water and the cone of depression (falls/rises) ___________to the level of water wells.

Question 28

Groundwater erupting from geysers which contains dissolved calcium carbonate will form deposits of___________or___________ ___________.

Question 29

The percentage of open space within the rock or sediment is known as its and its___________ capacity to transmit fluid is known as ___________.

Question 30

A(n) ___________is a permeable layer which transports water

Question 31

___________activity may be due to the heating of water by ___________or Earth's geothermal gradient.

Question 32

Hard water is a problem in areas underlain by ___________.

Question 33

the area above the water table in which water is held in tension in pores is known as the zone of___________.

Question 34

The cone of depression results when___________from the well is greater than___________to the well.

Question 35

Groundwater flows under the influence of ___________and___________ .

Question 36

___________are icicle-like structures hanging from cave ceilings that form as a result of precipitation of the mineral___________ .

Question 37

Explain why stalactites and stalagmites typically form in pairs and often merge to form a column.

Question 38

Why was the Yucca Mountain area selected for the national high-level radioactive waste repository?

Question 39

What are three reasons that some geologists are concerned about the Yucca Mountain site as a radioactive waste repository?

Question 40

Why is the High Plains Aquifer being depleted?

Question 41

Under what conditions does subsidence occur and why is this such a problem?

Question 42

Which major use requires the most groundwater, and to what percentage, in the United States?

Question 43

What is groundwater?

Question 44

Approximately what percentage of Earth's fresh water is groundwater?

Question 45

How does groundwater eventually return to the rest of the hydrologic cycle?

Question 46

What is an aquiclude?

Question 47

Briefly explain why shales have low permeability:

Question 48

What is the water table?

Question 49

In regions of moderate to high precipitation is the groundwater table a flat surface? Explain.

Question 50

What is the surface configuration of the groundwater table in arid regions?

Question 51

What happens to the water table during periods of drought?

Question 52

What is meant by the term recharge, as used in connection with groundwater?

Question 53

Where does groundwater discharge naturally?

Question 54

What is a spring?

Question 55

What causes a perched water table?

Question 56

Why can large cones of depression be a serious problem in some areas?

Question 57

What three geologic conditions which must exist for an artesian system to form?

Question 58

What is an artesian system?

Question 59

What is an example of a large and well-known artesian aquifer in the central United States?

Question 60

In what climatic conditions does karst topography best develop?

Question 61

What is dripstone?

Question 62

What causes a disappearing stream to disappear?

Question 63

Distinguish stalactites from stalagmites.

Question 64

Briefly explain how karst topography such as that in west Texas and New Mexico can be present despite arid to semi-arid climates.

Question 65

The High Plains aquifer accounts for about 30% of the groundwater usage for what purpose in the United States?

Question 66

How is hard water softened?

Question 67

How does groundwater become acidic?

Question 68

What causes the subsidence which is sometimes associated with groundwater use?

Question 69

Why is clay used to line the sides of landfills?

Question 70

List four of the specific toxic materials found in landfills and illegal dumps which can contaminate groundwater.

Question 71

List four specific toxic substances which can enter the groundwater in small quantities over large areas.

Question 72

For safe disposal of high-level radioactive waste, how long must the material remain isolated from the environment?

Question 73

Why are high-level radioactive wastes considered extremely dangerous?

Question 74

Where are most of the hot springs in the United States located?

Question 75

What are three world famous regions which contain large numbers of geysers?