freshwater and freshwater pollutants. what’s in the water? dissolved organics and inorganics ...
TRANSCRIPT
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Freshwater and Freshwater Pollutants
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What’s in the Water?
Dissolved organics and inorganics Particulate organics and inorganics Gases – oxygen and carbon dioxide Anthropogenic inputs, effects
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"any biological, chemical, or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses."
Water Pollution
44% of lakes,37% of rives unsafe for recreation due to toxic water pollutants32% of estuaries.
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1) Biological pathogens
2) Physical pollutants
3) Chemical pollutants
Basic Types of Pollution
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Viruses
Protozoa
Parasites
Bacteria
Pathogens
TyphoidCholeraDysentery
HepatitisPolio
Schistosomiasis
Amoebic dysentery
Giardiasis
Each year, about 1.5 million Americans become ill as a result of bacterial contamination in drinking water
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Physical Pollutants
Sediment
Heat
erosion, deforestation, agriculture
electric power plants – O2, thermal shock
chokes and fills lakes, reservoirs
reduced photosynthesis
½ of water withdrawn
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Chemical Pollutants
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Nutrients
Chemical Pollutants
Nitrogen Phosphorus
NO3-
NH4+
HPO4-2
H2PO-
animal wastes, agricultural runoff, and sewage
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ArsenicErosion of natural deposits; runoff from orchards, runoff from glass & electronics production wastes, treated lumber, groundwater
MercuryErosion of natural deposits; discharge from refineries and factories; runoff from landfills, coal burning
LeadCorrosion of household plumbing systems; erosion of natural deposits, paint, fuels
Heavy Metals and Metalloids
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Metal Common Health Effects
Lead
behavioral problemshigh blood pressure, anemiakidney damagememory and learning difficultiesmiscarriage, decreased sperm productionreduced IQ
Mercury
blindness and deafness brain damagedigestive problemskidney damagelack of coordinationcognitive degeneration
Arsenic
breathing problemsdeath if exposed to high levelsdecreased intelligenceknown human carcinogen: lung and skin cancernausea, diarrhea, vomitingperipheral nervous system problems
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Lead found in blood sample from 1 of 10 Washingtonians
Arsenic found in urine samples from 4 of 10 Washingtonians
Mercury found in hair samples from 10 of 10 Washingtonians
Mercury, Arsenic, and Lead
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Mercury Nitrate
Symptoms included tremors, emotional instability, insomnia, dementia and hallucinations
Wonderland
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Petroleum
Chemical Pollutants
three to six million metric tons
Exxon Valdez - 300,000 birds and 2,500 otters were killed
Spills account for about 5% of petroleum entering waterways.
oil changes, bilge cleaning and ship maintenance, recreational boating.
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2-cycle engines emit 30 times more hydrocarbonsIn its exhaust compared to 4 cycle engines.
Conventional Outboard Motors: 25-30% of their fuel unburned
75 percent reduction in outboard hydrocarbon emissions by 2006
Four cycle outboards easily meet the EPAs 2006 emissions standards, and they are also quieter and up to 40 percent more fuel efficient than two stroke motors. However, they are also 30 percent more expensive, heavier and more complex, making maintenance more difficult.
Outboard Motors
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Organic Chemicals
PesticidesIndustry
Solvents/CleaningFlame Retardants
DDTPCBs
TCE /PCEPBDE
http://www.npr.org/templates/story/story.php?storyId=6100179
Potentially highly toxicPersistent in the environment
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Where does it come from?
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Population Dynamics
YearYear Urban Urban PopulationPopulation
% of Total % of Total PopulationPopulation
17901790 201, 656201, 656 55
18601860 6,216,5186,216,518 2020
19201920 54, 263, 28254, 263, 282 5151
19901990 187,053,487187,053,487 7575
20002000 222,353,453222,353,453 7979
IndustrialRevolution
In 1987 the Clean Water Act was reauthorized with newprovisions to address a new source of pollution, urbanization
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Two Basic Avenues of Water Pollution
Point source pollution
Specific entry pointIndustrial dischargesSewage treatment plantsLandfills
Non-point source pollution
Diffuse sourcesDifficult to trace, regulate
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Non-point Source Pollution
Lawns, GardensGolf CoursesAgriculture
Urban Runoff
FertilizersPesticidesAnimal WastesOil, gas, rubber
Golf Courses Agriculture Urban
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Point Source Pollution
Factories/IndustryWastewater Treatment
LandfillsUnderground Storage Tanks
Mines
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Factories and Wastewater treatment
Often located near waterways (pollute and dilute)
1900 40% of river pollution1968 80% of river pollution
1972 Passage of the Clean Water Act
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Landfills
Prior to the 1970s
Dissolved pollutants = leachate
Paint, solvents, oil, cleaning agents
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Underground Storage Tanks
Gasoline, solvents
Steel – corrosion - Leaking
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Butler Plaza was formerly the location of the Stengal Airfield, which was an old US Army Air Corps pilot training center that was founded in 1942. An oil house with underground storage tanks (USTs) included a 10,000 gallon tank and a 4,000 gallon tank containing 90-octane fuel. After World War II, the training center was closed. Butler Plaza was built on top of the old hanger area in 1974.
In 1985, the DEP Northeast District requested that the Operation Response Section conduct a groundwater contamination source identification study for volatile organic contamination (VOC) found in two private wells in a residential area. They were contaminated with trichloroethylene (TCE) and perchloroethylene (PCE).
The supply wells were shut down and all areas were hooked to city water. Evaluation of groundwater monitoring data indicated that the Floridan aquifer had been impacted by VOC contamination in two areas.
According to the groundwater investigation reports, the primary source of the chlorinated solvent-related groundwater contamination is in the vicinity of one of the old airfield hangers formerly located at a spot covered by the Butler Plaza.
Gainesville
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Two Basic Avenues of Water Pollution
Point source pollution
Specific entry pointIndustrial dischargesSewage treatment plantsIndustryLandfillsUSTs
Non-point source pollution
Diffuse sourcesDifficult to trace, regulate
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Point and Non-Point Pollution
Example
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Superior
Michigan
Erie
OntarioHuron
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Shallowest of the Great Lakesaverage depth = 62 feet
Most populated
agriculture
Largest population density of Great Lakes
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Heavy Metals
Point and Non-Point Source Pollution
Industrial Chemicals
Petroleum
Nutrients and Pesticides
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A Dead Lake?
Non-point Source Pollution
Blue-green algaephytoplankton
O2
Nitrogen and Phosphorus
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Point Sources
lip papillomas
petroleum, PCBs, PAHs
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Cuyahoga River Fire (1969)
Petrochemicals
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Clean Water Act: 1972
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End of Lecture 22
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Determining Water Quality
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BiologicalMetals
NutrientsOrganic Chemicals
TurbidityTemperature/Dissolved O2
pH Salinity
Basic Water Quality Parameters
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Turbidity and Biological Contaminants
Often related to dissolved or suspended organic materials
Organic materials are consumed by heterotrophic microorganisms
Higher turbidity levels are often associated with higher levels of disease-causing microorganisms such as viruses, parasites and some bacteria.
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BOD measures the rate of oxygen uptake by micro-organisms in a sample of water at a fixed temperature (20°C) and over a given period of time in the dark.
Biological Oxygen Demand
pristine rivers will have a 5-day BOD below 1 mg/l.
Moderately polluted rivers BOD values in the range of 2 to 8 mg/l.
efficiently treated municipal sewage has a value of 20 mg/l.
Untreated sewage varies, but average around 600 mg/l in Europe and as low as 200 mg/l in the U.S
Due to microbial breakdown of organic materials in water
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pH, Temperature, Oxygen, and Salinity
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pH
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pH (hydrogen)
Low pH = High H+
H+
pH 2 = 0.01 g H+/ L pH 8 = 0.00000001 g H+/ L
Acid: any substance whichincreases the hydrogen ionconcentration in water.
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H2PO4- HPO4
2-pH
Low pH High pH
Availability and Form of Nutrients or Metals
Fe, Zn, Mg, Mn, Cu, Al, S, N, Mo
Micronutrients and metals generally more available at lower pH
High H+ conc. low H+ conc.
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Cr2O3 + 6H+ 2Cr3+ + 3H2O
InsolubleIn water
solubleIn water
Availability and Form of Metals
Dissolution of metal oxides increases their mobility
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Temperature
municipal
industrial
Industrial Coolingasphalt and concrete pavement
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Cooling Water billions of m3 (%) Electric Power 153.7 81.23Primary Metals 12.8 6.76Chemical and Products 11.8 6.24 Petroleum and Coal 4.6 2.43 Paper and Products 2.30 1.21 Food 1.48 0.78 Machinery 0.620 0.34 Rubber and Plastics 0.484 0.26 Transportation 0.386 0.21 All Other 1.03 0.54 Totals 189.2 100,0
Temperature
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Temperature
Poikilothermic Organisms
Changes in the growth rates of cold-blooded aquatic organisms and many biochemical reaction rates can often be approximated by a rule which predicts that growth rates will double if temperature increases by 10°C (18°F) within their "preferred" range
Fish, insects, zooplankton, phytoplankton, bacteria
Increased temperature, however, impacts dissolved oxygen contents.
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Temperature and Oxygen
The solubility of oxygen in water is highly temperature dependent.
Oxygen
10.1 mg/L 8.3 mg/L
15oC 25oC
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Oxygen is water soluble, but its solubility is temperature-dependent.
Cold water species: 5 mg/L TroutCool water species: 4 mg/L PikeWarm water species: 2-3 mg/L Bass, Catfish, Bluegill
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Stirring and agitation increases oxygen content
Cooler Water
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SO4-2 HS-
O2
NO3-
SO4-2
Still Ponds
C6H12O6 + 3SO42- + 3H+ = 6HCO3
- + 3HS-
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Oxygen
Oxygen is water soluble, but its solubility is temperature-dependent.In the atmosphere, about one out of 5 molecules is oxygen; in water, about one out of every 100,000 molecules is oxygen.
Oxygen enters the water body from the atmosphereand from photosynthesis near the surface
Oxygen leaves the water column principally by organism respiration.
Oxygen contents of water bodies generally is higher at the surface than at depth.
Stirring and agitation increases water’s oxygen content