Groundwater

Section 10.1

1. About 97% of the HYDROSPHERE is contained in the oceans.

2. The POLAR ICE CAPS and glaciers hold about 90% of Earth’s freshwater.

3. Only a very small amount of all the Earth’s liquid FRESHWATER is contained in rivers, streams, and lakes.

4. Water evaporates from seawater and forms invisible WATER VAPOR and visible clouds.

5. The winds and WEATHER SYSTEMS move the atmospheric water all over Earth.

6. PRECIPITATION, mostly in the form of rain and snow, falls into the oceans and on the land.

7. Precipitation that falls on land enters the ground through the process of INFILTRATION and becomes groundwater.

8. Small openings in subsurface Earth materials are pores, and the percentage of pore space in a material is its POROSITY.

10., 11., 12.

10. ZONE OF AERATION

11. WATER TABLE

12. ZONE OF SATURATION

13. Depth below Earth’s surface at which groundwater completely fills all the pores of a material

13. F ZONE OF SATURATION

14. Permeable layers through which groundwater flows

14. A AQUIFER

15. Upper boundary of the zone of saturation

15. D WATER TABLE

16. Ability of a material to let water pass through it

16. C PERMEABILITY

17. Water found in the zone of saturation

17. B GROUNDWATER

18. Zone below the surface, but above the zone of saturation, where materials are moist

18. E ZONE OF AERATION

19. What is gravitational water?

19. Gravitational water is water that trickles downward because of the force of gravity.

20. What is capillary water?

20. Capillary water is water that is drawn upward from the water table and held in the pore spaces because of surface tension.

21. How does the depth of the water table differ in stream valleys, swampy areas, and hilltops?

21. Stream Valleys - close to surface Swampy areas - at surface Hilltops - tens to hundreds of meters below the surface

Section 10.3

1. Natural discharge sites for groundwater on Earth’s surface are SPRINGS.

In contrast to air temperatures, groundwater is colder in the summer and warmer in the winter

2. However, in some regions of the United States, HOT SPRINGS will give off very warm or hot water.

3. Explosive hot springs that erupt on a regular basis are GEYSERS

True or False

4. Some lakes are fed by karst springs, which are like underground rivers emerging from the ground.

4. True

5. All springs have essentially the same temperature of water

5. False statements that say ALWAYS, ALL or NEVER are normally not True

6. Geysers are hot springs that erupt at regular intervals.

6. True

7. To obtain water, a WELL must tap into an aquifer.

8. The difference between the original water-table level and the water level in the pumped well is called the DRAWDOWN.

9. In order for the water supply of the wells to be replenished, water from precipitation and runoff must RECHARGE the zone of saturation.

10. An ARTESIAN WELL contains water that is under pressure, which may cause that well water to spurt into the air.

True or False

11. To produce water, a well must be drilled deep into aquicludes.

11. False To produce water, a well must be drilled into the aquifer (zone of saturation)

12. It is very difficult to cause drawdown in and aquifer, no matter how many wells are tapped into the aquifer

12. False Many wells will cause ground water levels to lower

13. An important artesian aquifer in the United States is the Ogallala Aquifer

13. True

14. What are four common sources of groundwater pollution?

14. sewage, industrial waste, landfills, agricultural chemicals

15. What are two natural pollutants?

15. Salt and Radioactive Radon Gas

16. How can salt get into freshwater supplies?

16. Overpumping of wells can cause underlying salt water to rise into the wells and contaminate the freshwater aquifer.

17. Where does radon originate?

17. Radon is generated by the radioactive decay of uranium in rocks and sediments, especially granite and shale.

True or False

18. Subsidence is caused by flooding caves

18. False

19. Most pollution plumes spread extremely slowly, and time is available for alternate water supplies to be found.

19. True

20. Most chemical contaminants can be removed easily from the groundwater and aquifers

20. False

21. If the recharge areas of confined aquifers are polluted, then the aquifer becomes polluted, too.

21. True