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December 3, 2008 WASHINGTON – The Environmental Protection Agency yesterday approved a last- minute rule change by the Bush administration that will allow.

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Presentation on theme: "December 3, 2008 WASHINGTON – The Environmental Protection Agency yesterday approved a last- minute rule change by the Bush administration that will allow."— Presentation transcript:

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2 December 3, 2008 WASHINGTON – The Environmental Protection Agency yesterday approved a last- minute rule change by the Bush administration that will allow coal companies to bury streams under the rocks, dirt and sludge from mining. A 1983 rule prohibited dumping fill from mountaintop removal mining within 100 feet of streams. In practice, the EPA hadn't been enforcing the rule under the Bush Administration. Government figures show that 535 miles of streams were buried or diverted from 2001 to 2005, more than half of them in the mountains of Appalachia. Along with the loss of the streams has been an increase of erosion and flooding. The 11th-hour change before President Bush leaves office would eliminate a tool that citizens groups have used in lawsuits to keep mining waste out of streams. Mining companies had been pushing for the change for years. In approving the change in writing as required by law, EPA Administrator Stephen Johnson rejected the appeals of environmentalists and some coal-country officials, including Kentucky Gov. Steve Beshear and Tennessee Gov. Phil Bredesen.

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4 In March, 2009, the Obama Administration began re-examining mountaintop-mining permits issued under Bush, putting a hold on six permits that had been issued, and announcing that as many as 200 other permits would also be scrutinized for their environmental impacts. The administration also announced it was reversing the Bush 2008 Rule that had weakened restrictions on mountaintop mining near water bodies. Mountaintop mining, environmentalists say, has now smothered more than 1,200 miles of streams in Appalachia.

5 Water: Resources and Pollution 1.Water Resources 2.Water Availability and Use 3.Water Pollution 4.Water Quality Today Water Legislation U. S. World Problems

6 1. Water Resources Water covers 75% of Earths surface Oceans: 70% Ice & Snow: 4% Rivers, Lakes, Wetlands: < 1%

7 Major water compartments > 97% of worlds water is saline ocean water < 3% of worlds water is fresh 87% of this is in glaciers, ice caps, and snowfields 12% is in groundwater < 1% of freshwater is surface water (lakes, ponds, rivers, streams) (this is 0.02% of all water on Earth!)

8 Figure 10.3

9 Fresh Water Resources Depend on Precipitation Patterns [Creates water-rich & water poor countries] Figure 10.2

10 Groundwater Largest reservoir of liquid fresh water Aquifers - Porous layers of rock holding water Artesian - Pressurized aquifer (springs, etc) Recharge Zone - Area where water enters an aquifer - Recharge rate is often very slow - Groundwater is often removed faster than recharge

11 Surface & Groundwater supplies interact in many ways Precipitation > Recharge zone Runoff > Stream flow - Discharge Aquifer - Water table

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13 2. Water Availability & Uses Surface Water (Renewable) ~80% of human supply Subject to great variation in dry regions, such as the western U. S. Groundwater (Nonrenewable?) ~20% of human supply (but > 40% in U. S.) Many aquifers are now subject to overdrafts (used at rates which exceed recharge rates)

14 Water Use & Distribution: ~70% of worlds water is used for agriculture ~20% is used by households ~10% is used by industry Some terms: Withdrawal - Amount of water taken from a source Consumption - Water not returned to its source Degradation - Contamination making it is unsuitable for desired use

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16 Worldwide Water Availability & Use WHO estimates that people require 1000 m 3 per person per year (265,000 gallons!) Big problem is uneven distribution Every continent has regions with scarce rainfall Natural drought cycles create temporary shortages Climatic changes (global warming) may alter supplies

17 a. World Freshwater Shortages 1 billion people lack adequate supplies of safe drinking water (typically carry water from distant source to home) 2.5 Billion lack adequate sanitation 45 countries face serious water stress (= lack of adequate supply) (mostly Africa & Middle East)

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19 Water 5 to possibly 25% of global freshwater use exceeds long-term accessible supplies (low to medium certainty) % of irrigation withdrawals exceed supply rates and are therefore unsustainable (low to medium certainty)

20 Dams / Reservoirs Huge evaporation losses Siltation > storage capacity Upsets natural balance of water systems Ecosystem Losses (wetlands, riparian) - Loss of wildlife habitat - Loss of free flowing river ecosystems Diversion systems drain & destroy aquatic systems and their ecological services b. Surface Water Depletion

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25 c. Groundwater Depletion Local depletion > Cone of depression Broad scale depletion > Aquifer depletion Ogallala Aquifer - Great Plains All large desert cities have depleted aquifers - Phoenix, Tucson, Las Vegas Consequences: > possible land subsidence, saltwater intrusion > pollution of groundwater in areas of development

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29 d. Water Management & Conservation Domestic conservation ~ 1/2 of all water use is wasted Largest domestic use is toilet flushing! (Fig ) Significant amounts of water could be recycled Agricultural water conservation Agric. is largest user (2/3 of total use) - Irrigate at the right time - Use conservative systems (e.g., drip irrig.) - Correct pricing structures

30 Price mechanisms and water policy In U.S., water policies have generally worked against conservation - Surface ownership rights (Eastern U.S.) or Prior appropriation rights (Western U.S.) Promotes use it or lose it attitudes - Dam and distribution system costs have been heavily subsidized Charging real costs would conservation

31 3. Types and Effects of Water Pollution Water pollution = Any physical, biological, or chemical change in water quality that adversely affects life Point Sources - Pollution from specific locations - Factories, Municipal sewage Non-Point Sources - Scattered or diffuse (no specific location of discharge) - Agricultural fields, Air pollution

32 Major Categories of Pollutants

33 a. Types (classes) of water pollution 1.Infectious Pathogens Sources: improperly treated human waste, agric. runoff (e.g., feedlots) Impacts: 2.5 billion people in LDCs lack adequate sanitation > water contamination - ~ 1 billion people lack clean drinking water ~ Cause 80% of all diseases in LDCs ~ 25 million deaths/year (if you include malaria, and yellow fever) - More than 500 pathogenic bacteria, viruses, and parasites can travel from human or animal excrement through water

34 2. Biological Oxygen-Demanding Wastes = Organic matter that is readily decomposed Sources: Agric. runoff, sewage Impacts: bacteria > O 2 > Aquatic life - O 2 is removed from water by respiration (decomposer bacteria) - Water with < 2 ppm dissolved O 2 will support only detritivores and decomposers

35 Oxygen Sag - O 2 levels decline downstream from a pollution source as decomposers metabolize waste materials

36 3. Plant Nutrients = Nitrates, phosphates, etc Sources: sewage, runoff, air pollution Impacts: algal bloom > light > algae death > O 2 > Aquatic life - Eutrophication - Process of increasing nutrient levels and biological productivity - Oligotrophic - few nutrients (clear water with low biological productivity) - Eutrophic - nutrient rich water (high productivity)

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38 4. Toxic Inorganic Pollutants Include: - Toxic metals such as mercury, lead, cadmium - Salts, acids, bases (in high concentrations) Sources: industrial wastes, mine runoff, homes (e.g., lead in pipes) Impacts: water quality ( uses), Aquatic life (metals bioaccumulate)

39 5. Organic Chemicals Include: 1000s of natural and synthetic organic chemicals found in pesticides, plastics, pigments, oil, etc. Sources: Industrial and household wastes, runoff of pesticides from high-use areas Impacts: water quality ( uses), Aquatic life (many organic molecules bioaccumulate)

40 6. Sediments = Insoluble suspended matter Sources: runoff (soil), sewage, atmos. dust - Human-induced erosion and runoff > sediments (greatest single cause of water pollution) Impacts: light > Psn > Food Chains - Also smothers benthic life and spawning areas

41 b. Water Quality Today Major success story (Legislation that works plus EPA oversight) In 1950s, many rivers/lakes badly polluted (some rivers caught on fire from oil poll.!) (Lake Erie had virtually no fish) In 1999, EPA reported 91.4% of all river miles and 87.5% of all lake areas suitable for their designated uses

42 Cuyahoga River Fires in Cleveland, Ohio 1969

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44 Clean Water Act (1972) established a National Pollution Discharge System, which requires a permit for any entity dumping wastes in surface waters - Discharge permits are required for all point sources - No discharge allowed for 126 priority pollutants - Goal was to return all U.S. surface waters tofishable and swimmable condition (these are the 2 key criteria established by CWA)

45 Major areas of progress: - Most progress due to municipal sewage treatment facilities - In 1997, EPA switched regulatory approaches: Now focus on watershed-level monitoring and protection - States are required to identify waters not meeting water quality goals and develop approaches to meet water quality goals

46 Remaining Problem Areas (Local & Global) Greatest problems are from non-point sources: include sediments, nutrients, and pathogens 3/4 of water pollution in the US comes from soil erosion, agricultural and urban runoff, and air pollution deposition - Feedlots produce 144 million tons of waste/year Atmospheric Deposition - Contaminants from air deposited into watersheds or directly onto surface waters - Great Lakes estimated to contain > 1 million pounds of the herbicide atrazine

47 Groundwater contamination: Half the US population (95% of rural pop.) rely on aquifers for drinking water For decades, seepage has contaminated aquifers - ~1 trillion gallons of contaminated water seep into the ground every day - Fertilizers and pesticides contaminate aquifers and wells in rural aquifers - Oil, & MTBE is present in many urban aquifers Largest aquifer in San Diego Co. is contaminated with oil Natural gas extraction contaminates aquifers with dozens of unknown chemicals (thanks to Bush loophole in water laws)

48 Groundwater Pollution

49 Drinking water: 1.5 million Americans fall ill from fecal contamination annually Some pathogens resistant to treatment Cryptosporidium outbreaks

50 Ocean Pollution: 6 million metric tons of trash and litter tossed from ships into the ocean annually Most coastlines contaminated by oil & pollution

51 The oceans garbage patches Charles Moore founded the Algalita Foundation in 1998 after sailing a catamaran from Hawaii, which took him through the Great Pacific Gyre It began with a line of plastic bags ghosting the surface, followed by an ugly tangle of junk: nets and ropes and bottles, motor-oil jugs and cracked bath toys, a mangled tarp. Tires. A traffic cone. Moore could not believe his eyes. Out here in this desolate place, the water was a stew of plastic crap. There is 6 times more plastic than plankton in this area, which is twice the size of Texas

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55 Water pollution problems in other countries: In Russia, only about half of the tap water supply is safe to drink In urban areas of South America, Africa, and Asia, 95% of all sewage is discharged untreated into rivers 2/3 of Indias surface waters dangerous to human health 2/3 of Chinas surface water is unsafe for humans


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