Lecture 1
Water
Fetter 1.1 and 1.2
Consumption of Water
Consumer |
Usage |
| Humans | need approximately 3 L of water/day |
| The average household | uses 200 - 300 gal/day |
| Flagstaff, Arizona | ~ 125 gal/day (winter) |
| ~ 170 gal/day (summer) | |
| In the U.S. | ~ 40% ground water |
| ~ 60% surface water | |
| 338 billion gallons of fresh water/day (1990) | |
| In Arizona (1985) | ~ 48% ground water |
| ~ 52% surface water | |
| Used in Arizona (1985) | ~ 87% Agriculture |
| ~ 9% Domestic/commercial | |
| ~ 3% Industrial/mining | |
| ~1% Electric/power |
| Physical properties of water and interactions of water with the environment are dependent on: | |
| 1) Atomic structure | |
| 2) Molecular structure | |
Water is an unusual substance.
Abundance of water in all three phases makes Earth unique as a planet in the Solar System.
Figure 1.1 Withdrawal of fresh water in the United States for all uses except
hydroelectric-power generation.
Figure 1.2 Per capita fresh-water usage in the United States for all uses
except hydroelectric-power generation.
| Molecular structure | ||
| 2 - Hydrogen atoms - 1 e- in outer shell | ||
| 1 - Oxygen atom - 6 e- in outer shell | ||
| 3 Forms a covalent bond ® Very strong!!! | ||
| 3 Water has an asymmetric molecular structure. | ||
| Water is a polar molecule. | |
3 Results in many unusual properties of water. |
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For instance, the polarity produces the ability for water to form hydrogen bonds
between other water molecules.
Also, this allows for surface tension, the ability for water to be attracted to itself
® capillarity.
| Chemical constituents can exist in the subsurface as | |
| 1) Separate gas or solid phases (CO2 or minerals) | |
| 2) Separate liquid phases (crude oil) | |
| 3) Mass dissolved in water (Na+ or Cl-) | |
| Historically, hydrogeologists have studied this occurrence of mass | |
General schematic diagram of a water molecule showing location of covalent bonds.
The Hydrologic Cycle Fetter 1.3 |
Total water supply of the world |
| Source | % Total |
| Oceans | 97.2% |
| Land | |
| Ice caps/Glaciers 2.14% (75% of land water) | |
| Ground water 0.61% | |
| Soil moisture 0.005% | |
| Fresh water lakes 0.001% | |
| Rivers 0.001% | |
| Saline Lakes 0.008% | |
| Total Land | 2.8% |
*Ground water is 98% of available freshwater
| Ground water | |
| Surface water | |
| Ocean water | |
| Atmospheric water | |
| As a modifier ® ground-water system |
| Hydrology | The study of water Inclusive of occurrence, distribution, movement and chemistry of all water of earth |
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| Hydrogeology | Interrelationships of geologic materials and processes with water |
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| Domenico & Schwartz (1990) | "The study of the laws governing the movement of subterraneous water, the mechanical, chemical, and thermal interactions of this water with the porous solid and the transport of energy and chemical constituents by the flow." |
| Not only is ground-water the largest source of fresh water, it is becoming smaller as | |
| 1) it is degraded | |
| 2) population increases, and uses more water | |
| What do hydrogeologists do? | ||||
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| Research | ||||
| 1) Basic Research: The search for first principles | ||||
| USGS, universities, National labs | ||||
| 2) Applied Research: Performed to solve a specific problem for private and public organizations | ||||
| "Clean water" projects | ||||
| ground water supply and control | ||||
| Economically driven | ||||
| Dewatering mines/construction | ||||
| Aquifer protection | ||||
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| "Dirty water" projects | ||||
| Satisfy legal/regulatory requirements | ||||
| RCRA - Resource Conservation and Recover Act | ||||
| treat, store, dispose of hazardous waste | ||||
| Work for owners, lawyers, consulting firm, public | ||||
Journals/Professional Organizations
| Journal | Professional Organization |
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| Ground Water | NGWA - AGWSE |
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| Ground Water Monitoring and Remediation | NGWA - AGWSE |
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| Journal of American Water Works Association | AWWA |
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| Hydrogeology Journal | GSA, IAH |
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| Journal of Contam. Hydrology | Elservier |
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| Journal of Hydrogeology | Elservier |
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| Water Resources Res. | AGU
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Sources of Data/Info
| USGS | Water Resources Division |
| Collects basic stream, low, surface-water quality, ground-water levels, ground-water quality | |
| Becoming more like a consulting firm | |
| Publishes a lot in Federal Document repositories | |
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| NGWA | Ground water online |
| Good bookstore | |
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| NOAA | (National Weather Service) |
Army Corps, BLM, SCS, EPA, USDA, DOE
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ENV 302 - Lectures
