Lecture chapter 22 - water pollution upload by raj kumar
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Transcript of Lecture chapter 22 - water pollution upload by raj kumar
Chapter Chapter ##2222Water PollutionWater Pollution
In-class Discussion In-class Discussion Readers:Readers:
Chapter Chapter ##1 - Me1 - MeChapter Chapter ##2 – David Dudley2 – David DudleyChapter Chapter ##3 – Elizabeth Goodrich3 – Elizabeth GoodrichChapter Chapter ##4 – James McLeod4 – James McLeodChapter Chapter ##5 – Labecca Hampton and 5 – Labecca Hampton and Jessica VidalJessica VidalChapter Chapter ##6 – Patrick Grennan and 6 – Patrick Grennan and Scott ArnoldScott ArnoldChapter Chapter ##7 – William Arnold7 – William ArnoldChapter Chapter ##8 – Crisy Overgard8 – Crisy OvergardChapter Chapter ##9 – Juan Rodriguez9 – Juan Rodriguez
OverviewOverviewo Types of Water PollutionTypes of Water Pollution
• SewageSewage• Disease-causing agentsDisease-causing agents• Sediment pollutionSediment pollution• Inorganic plant and algal nutrientsInorganic plant and algal nutrients• Organic compoundsOrganic compounds• Inorganic chemicalsInorganic chemicals• Thermal pollutionThermal pollution
o Water Quality TodayWater Quality Todayo Improving Water QualityImproving Water Qualityo Laws Controlling Water PollutionLaws Controlling Water Pollution
Types of Water PollutionTypes of Water Pollution
o Water pollutionWater pollution• Any physical or chemical change in water Any physical or chemical change in water
that adversely affects the health of humans that adversely affects the health of humans and other organisms and other organisms
• Varies in magnitude by locationVaries in magnitude by locationo Major water pollution issue globallyMajor water pollution issue globally
• Lack of disease-free waterLack of disease-free watero Eight categoriesEight categories
• Sewage, disease-causing agents, sediment Sewage, disease-causing agents, sediment pollution, inorganic plant and algal pollution, inorganic plant and algal nutrients, organic compounds, inorganic nutrients, organic compounds, inorganic chemicals, radioactive substances, and chemicals, radioactive substances, and thermal pollution thermal pollution
SewageSewage
o The release of wastewater from drains or The release of wastewater from drains or sewers sewers • Includes human wastes, soaps, and detergents Includes human wastes, soaps, and detergents
o Causes 2 serious environmental problems:Causes 2 serious environmental problems:• EnrichmentEnrichment
• Fertilization of a body of water by high levels of plant Fertilization of a body of water by high levels of plant and algal nutrients (nitrogen and phosphorus)and algal nutrients (nitrogen and phosphorus)
• Increase in Biological Oxygen Demand (BOD)Increase in Biological Oxygen Demand (BOD)• Amount of oxygen needed by microorganisms to Amount of oxygen needed by microorganisms to
decompose biological wastesdecompose biological wastes• As BOD increases Dissolve Oxygen (DO) decreasesAs BOD increases Dissolve Oxygen (DO) decreases
SewageSewage
Sewage- EutrophicationSewage- Eutrophicationo OligotrophicOligotrophic
• Unenriched, clear water that supports Unenriched, clear water that supports small populations of aquatic small populations of aquatic organisms organisms
Sewage- EutrophicationSewage- Eutrophicationo Eutrophic-Eutrophic-
• Slow-flowing stream, lake or estuary Slow-flowing stream, lake or estuary enriched by inorganic plant and algal enriched by inorganic plant and algal nutrients such as phosphorus nutrients such as phosphorus
• Often due to fertilizer or sewage runoffOften due to fertilizer or sewage runoff
Disease-causing AgentsDisease-causing Agents
o Infectious organisms Infectious organisms that cause diseasesthat cause diseases• Originate in the Originate in the
wastes of infected wastes of infected individuals individuals
o Common bacterial or Common bacterial or viral diseases:viral diseases:• Typhoid, cholera, Typhoid, cholera,
bacterial dysentery, bacterial dysentery, polio, and infectious polio, and infectious hepatitishepatitis
Disease-causing AgentsDisease-causing Agents
o Monitored by testing for presence of E. Monitored by testing for presence of E. coli in the water via a coli in the water via a fecal coliform fecal coliform testtest• Indicates the presence of pathogenic Indicates the presence of pathogenic
organismsorganisms
Sediment PollutionSediment Pollution
o Excessive amounts of suspended soil Excessive amounts of suspended soil particlesparticles• Originates from erosion of agricultural Originates from erosion of agricultural
lands, forest soils exposed by logging, lands, forest soils exposed by logging, degraded stream banks, overgrazed degraded stream banks, overgrazed rangelands, strip mines, and construction rangelands, strip mines, and construction
o ProblemsProblems• Limits light penetrationLimits light penetration• Covers aquatic animals and plantsCovers aquatic animals and plants• Brings insoluble toxins into waterwaysBrings insoluble toxins into waterways
Inorganic Plant and Algal Inorganic Plant and Algal NutrientsNutrients
o Chemicals such as nitrogen and Chemicals such as nitrogen and phosphorus that stimulate the growth of phosphorus that stimulate the growth of plants and algaeplants and algae• Harmful in large concentrationsHarmful in large concentrations
o Sources:Sources:• Human and animal wastes, plant residues, Human and animal wastes, plant residues,
atmospheric deposition, and fertilizer runoffatmospheric deposition, and fertilizer runoffo Causes:Causes:
• Enrichment, bad odors, and a high BOD Enrichment, bad odors, and a high BOD
Inorganic Plant and Algal Nutrient- Inorganic Plant and Algal Nutrient- The Dead ZoneThe Dead Zone
The Great Pacific The Great Pacific Patch of GarbagePatch of Garbage
Organic CompoundsOrganic Compounds
o Chemicals that contain carbon atomsChemicals that contain carbon atoms• Natural examples: sugars, amino acids, Natural examples: sugars, amino acids,
and oils and oils • Human-made examples: pesticides, Human-made examples: pesticides,
solvents, industrial chemicals, and plastics solvents, industrial chemicals, and plastics
Inorganic ChemicalsInorganic Chemicals
o Contaminants that contain elements Contaminants that contain elements other than carbonother than carbon• Examples: acids, salts, and heavy metals Examples: acids, salts, and heavy metals
o Do not degrade easilyDo not degrade easilyo LeadLead
• Found in old paint, industrial pollutants, Found in old paint, industrial pollutants, leaded gasolineleaded gasoline
o MercuryMercury• Mercury bioaccumulates in the muscles of Mercury bioaccumulates in the muscles of
top predators of the open ocean top predators of the open ocean
Radioactive SubstancesRadioactive Substances
o Contain atoms of unstable isotopes that Contain atoms of unstable isotopes that spontaneously emit radiation spontaneously emit radiation
o SourcesSources• MiningMining• Processing radioactive materialsProcessing radioactive materials• Nuclear power plantsNuclear power plants• Natural sourcesNatural sources
Thermal PollutionThermal Pollutiono Occurs when heated Occurs when heated
water produced water produced during industrial during industrial processes is released processes is released into waterways into waterways
o Organisms affectedOrganisms affected• Temperature affects Temperature affects
reproductive cycles, reproductive cycles, digestion rates, and digestion rates, and respiration rates respiration rates
• Warm water holds less Warm water holds less DO than cold waterDO than cold water
Water Quality TodayWater Quality Todayo Two Types of Water PollutionTwo Types of Water Pollutiono -Point Source Pollution-Point Source Pollution
• water pollution that can be traced to a water pollution that can be traced to a specific origin specific origin
• Discharge via pipes, sewage, and ditchesDischarge via pipes, sewage, and ditcheso -Non-point Source Pollution-Non-point Source Pollution
• Pollutants that enter bodies of water over Pollutants that enter bodies of water over large areas rather than being concentrated at large areas rather than being concentrated at a single point of entry a single point of entry
• Diffuse, but its cumulative effect is very largeDiffuse, but its cumulative effect is very large• Ex: runoff from agricultural fields or parking Ex: runoff from agricultural fields or parking
lotslots
Water Pollution from Water Pollution from AgricultureAgriculture
o Agriculture is leading source of water Agriculture is leading source of water pollution in USpollution in US• Animal wastes and plants residues have Animal wastes and plants residues have
high BODhigh BOD• Chemical pesticides can leach into Chemical pesticides can leach into
groundwatergroundwatero Almost all streams and rivers are Almost all streams and rivers are
polluted with agricultural pesticidespolluted with agricultural pesticides
Municipal Water PollutionMunicipal Water Pollution
Industrial Wastes in WaterIndustrial Wastes in Water
o Different industries generate different Different industries generate different pollutantspollutants• Food processing plants- high BODFood processing plants- high BOD• Paper mills- High BOD and toxic compoundsPaper mills- High BOD and toxic compounds
o Many industries recover toxins before they go Many industries recover toxins before they go into the waste streaminto the waste stream
Case-In-Point Green ChemistryCase-In-Point Green Chemistry
Groundwater PollutionGroundwater Pollution
Water Pollution in Other Water Pollution in Other CountriesCountries
o Lake Maracaibo, VenezuelaLake Maracaibo, Venezuela• 10,000 oil wells tap lake bottom10,000 oil wells tap lake bottom
• Leak oil into lakeLeak oil into lake• Agricultural Agricultural
wastes from wastes from local fieldslocal fields
• Unit recently Unit recently raw human raw human waste polluted waste polluted the lakethe lake
Water Pollution in Other Water Pollution in Other CountriesCountries
o Po River, ItalyPo River, Italy• Similar to Mississippi River• Pollutants: Sewage, industrial wastes,
sediment• >16 million Italians depend on the river for
drinking water• Pollution is high
• Swimming and fishing prohibited• Cleanup will require a national
management plan and may take decades
Water Pollution in Other Water Pollution in Other CountriesCountries
o Ganges River, IndiaGanges River, India• Used for bathing and Used for bathing and
washing clothingwashing clothing• Sewage and industrial Sewage and industrial
waste discharged into waste discharged into riverriver
• Ganga Action Plan Ganga Action Plan initiated by governmentinitiated by government
• Construction of 29 Construction of 29 sewage treatment plantssewage treatment plants
Improving Water Quality-Improving Water Quality-Purification of Drinking WaterPurification of Drinking Water
o In US most In US most municipal water municipal water supplies are supplies are treated treated
o Collected from Collected from water or water or reservoirreservoir
o TreatedTreated
o Treated water Treated water distributed to distributed to customerscustomers
o Sewer lines bring Sewer lines bring sewage to sewage to treatment planttreatment plant
o Sewage treated at Sewage treated at sewage treatment sewage treatment plantplant
Improving Water Quality-Improving Water Quality-Purification of Drinking WaterPurification of Drinking Water
Purification of Drinking WaterPurification of Drinking Water
o Chlorine DilemmaChlorine Dilemma• Chlorine kills disease causing organismsChlorine kills disease causing organisms• Chlorine byproducts are linked to numerous Chlorine byproducts are linked to numerous
cancers, miscarriages and birth defectscancers, miscarriages and birth defects• Peru stopped using chlorinePeru stopped using chlorine
• 1991- huge cholera epidemic that infected 1991- huge cholera epidemic that infected 300,000 people300,000 people
o FluoridationFluoridation• Prevents tooth decayPrevents tooth decay• Linked to cancer, kidney diseaseLinked to cancer, kidney disease
Municipal Sewage TreatmentMunicipal Sewage Treatmento Primary treatmentPrimary treatment
• Removing suspended and floating particles by Removing suspended and floating particles by mechanical processes mechanical processes
o Secondary treatmentSecondary treatment• Treating wastewater biologically to decompose Treating wastewater biologically to decompose
suspended organic material; reduces BOD suspended organic material; reduces BOD
Municipal Sewage TreatmentMunicipal Sewage Treatment
o Sewage SludgeSewage Sludge• Solids remaining after primary and Solids remaining after primary and
secondary sewage treatment has been secondary sewage treatment has been completed completed
o Tertiary treatmentTertiary treatment• Advanced wastewater treatment methods Advanced wastewater treatment methods
that are sometimes employed after primary that are sometimes employed after primary and secondary treatments and secondary treatments
• Reduce phosphorus and nitrogenReduce phosphorus and nitrogen
Municipal Sewage TreatmentMunicipal Sewage Treatment
Individual Septic System-Individual Septic System-Septic TankSeptic Tank
Individual Septic System-Individual Septic System-Drain FieldDrain Field
Laws Controlling Water Laws Controlling Water PollutionPollution
o Citizen Watchdogs to Monitor PollutionCitizen Watchdogs to Monitor Pollutiono Safe Drinking Water Act (1974)Safe Drinking Water Act (1974)
• Set uniform federal standards for drinking Set uniform federal standards for drinking waterwater
• Maximum contaminant levelMaximum contaminant levelo Clean Water Act (1972)Clean Water Act (1972)
• EPA sets up and monitors National EPA sets up and monitors National Emissions LimitationsEmissions Limitations
• Effectively improved water quality from Effectively improved water quality from point sourcespoint sources
Laws that Protect GroundwaterLaws that Protect Groundwater
o Safe Drinking Water ActSafe Drinking Water Acto Resource, Conservation and Recovery Resource, Conservation and Recovery
ActAct