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1、Water PollutionChapter 21Chapter 21Identify what pollutes water and the source of the pollution.Identify the major pollution problems affecting our waterways including oceans, surface water and groundwaterDetermine methods to “clean up” water Describe state and federal water legislationVocabulary Wo
2、rdsWater pollutionpoint/non-point sourceBiological Oxygen Demand (BOD)Chemical Oxygen Demand (COD)sludgeSafe Drinking Water ActClean Water ActOil Spill Prevention & Liability ActIdentifying PollutionWhich of the beakers on the front table contain polluted water?Chlorine, specific conductanceAcid, pH
3、Organic constituents, lab analysisSediment, visual identificationSurfactants, visual identificationWe All Live Downstream“Today, everybody is downstream from somebody else,” William RuckelshausWhat does that mean?How does that affect your water quality?“Frontline: Poisoned Waters”http:/video.pbs.org
4、/video/1114515379/ Water PollutionWater pollution is any chemical, biological or physical change in water quality that has a harmful effect on living organisms or makes water unsuitable for desired uses.Who decides if water is “harmful”?What does “harmful” mean?Which “living organisms” matter?“All s
5、ubstances are poisons, there is none which is not a poison. The right dose differentiates a poison and a remedy.” Paracelsus (1493-1541)ToxicologyThe study of the interaction between chemical agents and biological systems.Toxicity is the relative ability of a substance to cause adverse effects in li
6、ving organisms.Definitions of “harmful”Toxic refers to a parameter, constituent to pollutant that has an LD50; in other words, it has been known to kill organisms (usually humans)Hazardous refers to a compound which causes acute or chronic health problems, including, but not limited to, death.The po
7、int is . . .If the chemicals and biological agents that we use and produce as waste products were not “harmful” in some way to some population, there would be no point in studying water pollution.The source of it allPoint source: pollution that comes from a specific locationSludge from a copper mine
8、.Industrial dischargeOther SourcesNon-point source: pollution that occurs from multiple sources with no single polluter identified.Who are the polluters?The major source of 41-48% water pollution is agriculture according to the EPA.Connect the dots from population growth, food production, water use
9、and water pollution.Industrial Facilities Municipal Mining What is water polluted with?Disease-causing agentsOxygen demanding wastePlant nutrients (NO3-, PO43-)Organic chemicals (solvents, petroleum)Inorganic chemicals (Fe, Pb, NH3)SedimentHeatWhat are they polluting?What else are they polluting?Eff
10、ects of PollutionThe two major effects of water pollution are:exposure to infectious agents from contaminated drinking water; and,not having enough water for effective sanitation.Waterborne DiseasesWhat is “clean” or “safe”?The definition of clean or safe water is very dependent on its use and the l
11、aws that affect the source and discharge of the water.Example: pHRCRA: 2 S.U. 12.5SDWA: 6.5 S.U. 8.5HMTA: those substances which cause visible destruction to skin tissueThe WaterDrinking Water: Safe Drinking Water ActSurface Water: Clean Water ActGroundwater: CWA, RCRA as Solid Waste, CERCLA for cle
12、an-upSurface WaterSurface Water is polluted by:human activityindustrial activitypower plantsFreshwater SourcesWater QualityThere are two classes of water quality standards:biologicalchemicalChemical Water QualityWater Quality Index (WQI) is a set of standard test parameters used to compare water qua
13、lity all around the country.An numerical WQI is assigned based on the results of nine (9) separate parametersWQI ParametersDissolved Oxygen (DO)pHTemperature Change (T)Fecal ColiformBiochemical Oxygen Demand (BOD)NitratesTotal PhosphatesTotal Dissolved Solids (TDS)Turbidity or Total Suspended Solids
14、 (TSS)Q ValueMeasurements of each parameter are taken and recorded and then are converted into a “Q value”Water Quality Factor WeightsThe “Q” value for each parameter is determined and multiplied by a weighting factor:Dissolved oxygen0.17Fecal coliform0.16pH0.11Biochemical oxygen demand0.11Temperatu
15、re change0.10Total phosphate0.10Nitrates0.10Turbidity0.08Total solids0.07Final calculationThe weighted “Q values” are added for all of the parameters and compared to a water quality index scaleThe ScaleWater Quality Index Scale91 - 100 : Excellent Water Quality71 - 90 : Good Water Quality51 - 70 : M
16、edium or Average Quality26 - 50 : Fair Water Quality 0 - 25 : Poor Water QualityDissolved OxygenOxygen gas is not very soluble in water. As the temperature of a liquid increases, the solubilities of gases in that liquid decrease. T, SolubilityGas SolubilityWe can use the Second Law of Thermodynamics
17、 to explain why. Heating a solution of a gas enables the particles of gas to move more freely between the solution and the gas phase. The Second Law predicts that they will shift to the more disordered, more highly dispersed, and therefore, more probably gas state.Where does DO come from?Most of the
18、 DO in surface water comes from contact with the atmosphere.Splashing and flowing water traps oxygenPhotosynthetic organisms also produce oxygenDO TestThe test for DO determines the availability of oxygen for aquatic lifeA high concentration of DO indicates high water qualityFig. 21-3, p. 496WaterQu
19、alityBelow 4Below 4.5DO (ppm) at 20C4.56.76.7889GravelypollutedHeavilypollutedModeratelypollutedSlightlypollutedGoodReferencehttp:/www.indiana.edu/bradwood/eagles/waterquality.htmPhysical Influences on Dissolved OxygenWater temperature and the volume of water moving down a river (discharge) affect d
20、issolved oxygen levels. Gases, like oxygen, dissolve more easily in cooler water than in warmer water. In temperate areas, rivers respond to changes in air temperature by cooling or warming.Climate and DORiver discharge is related to the climate of an area. During dry periods, flow may be severely r
21、educed, and air and water temperatures are often higher. Both of these factors tend to reduce dissolved oxygen levels. Wet weather or melting snows increase flow, with a resulting greater mixing of atmospheric oxygen.Human-Caused Changes in Dissolved OxygenThe main factor contributing to changes in
22、dissolved oxygen levels is the build- up of organic wastes. Organic wastes consist of anything that was once part of a living plant or animal, including food, leaves, feces, etc. Organic waste can enter rivers in sewage, urban and agricultural runoff, or in the discharge of food processing plants, m
23、eat packing houses, dairies, and other industrial sources.Farming and Dissolved OxygenA significant ingredient in urban and agricultural runoff are fertilizers that stimulate the growth of algae and other aquatic plants. As plants die, aerobic bacteria consume oxygen in the process of decomposition.
24、 Many kinds of bacteria also consume oxygen while decomposing sewage and other organic material in the river.Changes in Aquatic LifeDepletions in dissolved oxygen can cause major shifts in the kinds of aquatic organisms found in water bodies. Species that cannot tolerate low levels of dissolved oxyg
25、en-mayfly nymphs, stonefly nymphs, caddisfly larvae, and beetle larvae-will be replaced by a few kinds of pollution-tolerant organisms, such as worms and fly larvae. Nuisance algae and anaerobic organisms (that live without oxygen) may also become abundant in waters with low levels of dissolved oxyg
26、en.Calculating Percent SaturationThe percent saturation of water with dissolved oxygen at a given temperature is determined by pairing temperature of the water with the dissolved oxygen value, after first correcting your dissolved oxygen measurement for the effects of atmospheric pressure. This is d
27、one with the use of the correction table and the percent saturation chart. Using the Conversion ChartsTo calculate percent saturation, first correct your dissolved oxygen value (milligrams of oxygen per liter) for atmospheric pressure. Look at the correction chart. Using either your atmospheric pres
28、sure (as read from a barometer) or your local altitude (if a barometer is not available), read across to the right hand column to find the correction factor. Multiply your dissolved oxygen measurement by this factor to obtain a corrected value.The Meaning of Percent SaturationRivers that consistentl
29、y have a dissolved oxygen value of 90 percent or higher are considered healthy, unless the waters are supersaturated due to cultural eutrophication. Rivers below 90 percent saturation may have large amounts of oxygen-demanding materials, i.e. organic wastes.Biochemical Oxygen Demand (BOD)When organi
30、c matter decomposes, it is fed upon by aerobic bacteria. In this process, organic matter is broken down and oxidized (combined with oxygen). Biochemical oxygen demand is a measure of the quantity of oxygen used by these microorganisms in the aerobic oxidation of organic matter. Biochemical Oxygen De
31、mand (BOD)When aquatic plants die, they are fed upon by aerobic bacteria. The input of nutrients into a river, such as nitrates and phosphates, stimulates plant growth. Eventually, more plant growth leads to more plant decay. Nutrients, then, can be a prime contributor to high biochemical oxygen dem
32、and in rivers. Sources of Organic MatterThere are natural sources of organic material which include organic matter entering lakes and rivers from swamps, bogs, and vegetation along the water, particularly leaf fall.There are also human sources of organic material. When these are identifiable points
33、of discharge into rivers and lakes, they are called point sources. Point Sources of Organic MatterPoint sources of organic pollution include: pulp and paper mills; meat-packing plants; food processing industries; wastewater treatment plants. Non-point Sources of Organic MatterUrban runoff of rain an
34、d melting snow that carries sewage from illegal sanitary sewer connections into storm drains; pet wastes from streets and sidewalks; nutrients from lawn fertilizers; leaves, grass clippings, and paper from residential areas; Agricultural runoff that carries nutrients, like nitrogen and phosphates, f
35、rom fields; Runoff from animal feedlots that carries fecal material into rivers.Changes in Aquatic LifeIn rivers with high BOD levels, much of the available dissolved oxygen is consumed by aerobic bacteria, robbing other aquatic organisms of the oxygen they need to live. Organisms that are more tole
36、rant of lower dissolved oxygen may appear and become numerous, such as carp, midge larvae, and sewage worms. Organisms that are intolerant of low oxygen levels, such as caddisfly larvae, mayfly nymphs, and stonefly nymphs, will not survive. Cause and EffectAs organic pollution increases, the ecologi
37、cally stable and complex relationships present in waters containing a high diversity of organisms is replaced by a low diversity of pollution-tolerant organisms. Fig. 21-4, p. 4978 ppmBiologicaloxygendemandDissolvedoxygen(ppm)Types oforganisms8 ppmRecoveryZoneSeptic ZoneDecompositionZoneClean ZoneFi
38、sh absent,fungi, sludgeworms,bacteria(anaerobic)Trash fish(carp, gar,leeches)Clean Normal clean water organisms(Trout, perch, bass,mayfly, stonefly)Normal clean water organisms(Trout, perch, bass,mayfly, stonefly)Clean ZoneTrash fish(carp, gar,leeches)pHWater contains both H+ (hydrogen) ions and OH-
39、 (hydroxyl) ions. The pH test measures the H+ ion concentration of liquids and substances. Changes in pHIt is important to remember that for every one unit change on the pH scale, there is approximately a ten-fold change in how acidic or basic the sample is. The average pH of rainfall over much of t
40、he northeastern United States is 4.3, or roughly ten times more acidic than normal rainfall of 5.0-5.6. Lakes of pH 4 (acidic) are roughly 100 times more acidic than lakes of pH 6.Human-Caused Changes in pHIn the U.S., the pH of natural water is usually between 6.5 and 8.5, although wide variations
41、can occur. Increased amounts of nitrogen oxide (NOx) and sulfur dioxide (SO-2), primarily from automobile and coal-fired power plant emissions, are converted to nitric acid and sulfuric acid in the atmosphere. Acid NeutralizationAcid rain is responsible for thousands of lakes in eastern Canada, nort
42、heastern United States, Sweden, and Finland becoming acidic. If limestone is present, the alkaline (basic) limestone neutralizes the effect the acids might have on lakes and streams.The areas hardest hit by acid rain and snow are downwind of urban/industrial areas and do not have any limestone to re
43、duce the acidity of the water.Changes in Aquatic LifeChanges in the pH value of water are important to many organisms. Most organisms have adapted to life in water of a specific pH and may die if it changes even slightly. This has happened to brook trout in some streams in the Northeast.pH ExtremesA
44、t extremely high or low pH values (e.g., 9.6 or 4.5) the water becomes unsuitable for most organisms. For example, immature stages of aquatic insects and young fish are extremely sensitive to pH values below 5.Very acidic waters can also cause heavy metals, such as copper and aluminum, to be release
45、d into the water. NitratesNitrogen is a much more abundant nutrient than phosphorus in nature. Blue-green algae, the primary algae of algal blooms, are able to use N2 and convert it into forms of nitrogen that plants can take up through their roots and use for growth: ammonia (NH3) and nitrate (NO3-
46、).NitratesHow do aquatic animals obtain the nitrogen they need to form proteins? they either eat aquatic plants and convert plant proteins to specific animal proteins, or, they eat other aquatic organisms which feed upon plants.NitratesAs aquatic plants and animals die, bacteria break down large pro
47、tein molecules into ammonia. Ammonia is then oxidized (combined with oxygen) by specialized bacteria to form nitrites (NO2) and nitrates (NO-3). These bacteria get energy for metabolism from oxidation.NitratesExcretions of aquatic organisms are very rich in ammonia, although the amount of nitrogen t
48、hey add to waters is usually small. Duck and geese, however, contribute a heavy load of nitrogen (from excrement) in areas where they are plentiful. algae into ammonia and nitrates. EutrophicationEutrophication promotes more plant growth and decay, which in turn increases biochemical oxygen demand.
49、However, unlike phosphorus, nitrogen rarely limits plant growth, so plants are not as sensitive to increases in ammonia and nitrate levels.Sources of NitratesSewage is the main source of nitrates added by humans to rivers and lakes. Septic systems are common in rural areas. In properly functioning s
50、eptic systems, soil particles remove nutrients like nitrates and phosphates before they reach groundwater. Sources of NitratesWhen septic system drainfields are placed too close to the water table, nutrients and bacteria are able to percolate down into the groundwater where they may contaminate drin
51、king water supplies. Septic tanks must also be emptied periodically, to function properly. Problems with Nitrate Contaminated WaterWater containing high nitrate levels can cause a serious condition called methemoglobinemia (met-hemo-glo-bin-emia), if it is used for infant milk formula. This conditio
52、n prevents the babys blood from carrying oxygen; hence the nickname blue baby syndrome.Water TemperatureThe water temperature of a river is very important for water quality. Many of the physical, biological, and chemical characteristics of a river are directly affected by temperature. Temperature In
53、fluencesthe amount of oxygen that can be dissolved in water; the rate of photosynthesis by algae and larger aquatic plants; the metabolic rates of aquatic organisms; the sensitivity of organisms to toxic wastes, parasites, and diseases. Remember, cool water can hold more oxygen than warm water, beca
54、use gases are more easily dissolved in cool water. Human-Caused Changes in TemperatureThermal pollution is an increase in water temperature caused by adding relatively warm water to a body of water. Industries, such as nuclear power plants, may cause thermal pollution by discharging water used to co
55、ol machinery. Thermal pollution may also come from stormwater running off warmed urban surfaces, such as streets, sidewalks, and parking lots. Human Temperature People also affect water temperature by cutting down trees that help shade the river, exposing the water to direct sunlight. Soil erosion c
56、an also contribute to warmer water temperatures. Soil erosion raises water temperatures because it increases the amount of suspended solids carried by the river, making the water cloudy (turbid). Cloudy water absorbs the suns rays, causing water temperature to rise. Changes in Aquatic LifeAs water t
57、emperature rises, the rate of photosynthesis and plant growth also increases. More plants grow and die. As plants die, they are decomposed by bacteria that consume oxygen. Therefore, when the rate of photosynthesis is increased, the need for oxygen in the water (BOD) is also increased. Hot AnimalsTh
58、e metabolic rate of organisms also rises with increasing water temperatures, resulting in even greater oxygen demand. The life cycles of aquatic insects tend to speed up in warm water. Animals that feed on these insects can be negatively affected, particularly birds that depend on insects emerging a
59、t key periods during their migratory flights. Temperature AdaptationsMost aquatic organisms have adapted to survive within a range of water temperatures. Some organisms prefer cooler water, such as trout, stonefly nymphs, while others thrive under warmer conditions, such as carp and dragonfly nymphs
60、. As the temperature of a river increases, cool water species will be replaced by warm water organisms. Temperature and ToxicityTemperature also affects aquatic lifes sensitivity to toxic wastes, parasites, and disease. Thermal pollution may cause fish to become more vulnerable to disease, either du
61、e to the stress of rising water temperatures or the resulting decrease in dissolved oxygen.TurbidityTurbidity is a measure of the relative clarity of water: the greater the turbidity, the murkier the water. Turbidity increases as a result of suspended solids in the water that reduce the transmission
62、 of light. Suspended solids are varied, ranging from clay, silt, and plankton, to industrial wastes and sewage.Sources of TurbidityHigh turbidity may be caused by soil erosion, waste discharge, urban runoff, abundant bottom feeders (such as carp) that stir up bottom sediments, or algal growth. The p
63、resence of suspended solids may cause color changes in water, from nearly white to red-brown, or to green from algal blooms. Changes in Aquatic LifeAt higher levels of turbidity, water loses its ability to support a diversity of aquatic organisms. Waters become warmer as suspended particles absorb h
64、eat from sunlight, causing oxygen levels to fall (warm water, less O2). Photosynthesis decreases because less light penetrates the water, causing further drops in oxygen levels. The combination of warmer water, less light, and oxygen depletion makes it impossible for some forms of aquatic life to su
65、rvive. Suspended SolidsSuspended solids can clog fish gills, reduce growth rates, decrease resistance to disease, and prevent egg and larval development. Particles of silt, clay, and organic materials can smother the eggs of fish and aquatic insects, as well as suffocate newly-hatched insect larvae.
66、 Material that settles into the spaces between rocks makes these microhabitats unsuitable for mayfly nymphs, stonefly nymphs, caddisfly larvae, and other aquatic insects living there. Fecal Coliform BacteriaFecal coliform bacteria are found in the feces of humans and other warm-blooded animals. Thes
67、e bacteria can enter rivers directly or from agricultural and storm runoff carrying wastes from birds and mammals, and from human sewage discharged into the water. Pathogenic OrganismsFecal coliform by themselves are not dangerous (pathogenic) . Fecal coliform bacteria naturally occur in the human d
68、igestive tract, and aid in the digestion of food. In infected individuals, pathogenic organisms are found along with fecal coliform bacteria. Presence of Both If fecal coliform counts are high (over 200 colonies/100 ml of water sample) in the river, there is a greater chance that pathogenic organism
69、s are also present. Diseases and illness such as typhoid fever, hepatitis, gastroenteritis, dysentery, and ear infections can be contracted in waters with high fecal coliform counts. What to monitor?Pathogens are relatively scarce in water, making them difficult and time-consuming to monitor directl
70、y. Instead, fecal coliform levels are monitored, because of the correlation between fecal coliform counts and the probability of contracting a disease from the water. Municipal MonitoringSanitary wastes (from toilets, washers, and sinks) flow through sanitary sewers and are treated at the wastewater
71、 treatment plant. Storm sewers carry rain and snow melt from streets, and discharge untreated water directly into rivers. Heavy rains and melting snow wash animal wastes from sidewalks and streets and may wash fecal coliform into the storm sewers. StandardsPhosphorusPhosphorus is usually present in
72、natural waters as phosphate .Organic phosphate is a part of living plants and animals, their by-products, and their remains. Inorganic phosphates are ions and are bonded to soil particles; there are some phosphates present in laundry detergents. Phosphorus is essentialPhosphorus is a plant nutrient
73、needed for growth, and a fundamental element in the metabolic reactions of plants and animals. Plant growth is limited by the amount of phosphorus available. In most waters, phosphorus functions as a growth-limiting factor because it is usually present in very low concentrations. Phosphorus is scarc
74、eThe natural scarcity of phosphorus can be explained by its attraction to organic matter and soil particles. Any unattached or “free phosphorus, in the form of inorganic phosphates, is rapidly taken up by algae and larger aquatic plants. Because algae only require small amounts of phosphorus to live
75、, excess phosphorus causes extensive algal growth called blooms.EutrophicationMost of the eutrophication occurring today is human-caused (cultural eutrophication). Phosphorus from natural sources generally becomes trapped in bottom sediments or is rapidly taken up by aquatic plants. Forest fires and
76、 fallout from volcanic eruptions are natural events that cause eutrophication. Sources of PhosphorusPhosphorus comes from several sources: human wastes, animal wastes, industrial wastes, and human disturbance of the land and its vegetation.Sewage effluent (out flow) should not contain more than 1 mg
77、/ L phosphorus according to the U.S. EPA. Sources of PStorm sewers sometimes contain illegal connections to sanitary sewers. Sewage from these connections can be carried into waterways by rainfall and melting snow. Phosphorus-containing animal wastes sometimes find their way into rivers and lakes in
78、 the runoff from feedlots and barnyards. Erosion is a sourceSoil erosion contributes phosphorus to rivers. The removal of natural vegetation for farming or construction exposes soil to the eroding action of rain and melting snow.Draining swamps and marshes for farmland or construction projects relea
79、ses phosphorus that has remained dormant in years of accumulated organic deposits. Drained wetlands no longer function as filters of silt and phosphorus, allowing more runoff -and phosphorus- to enter waterways. Impacts of Cultural EutrophicationThe first symptom of cultural eutrophication is an alg
80、al bloom that colors the water a pea-soup green. The advanced stages of cultural eutrophication can produce anaerobic conditions in which oxygen in the water is completely depleted. These conditions usually occur near the bottom of a lake or impounded river stretch, and produce gases like hydrogen s
81、ulfide, unmistakable for its rotten egg smell.Changes in Aquatic LifeCultural eutrophication causes a shift in aquatic life to a fewer number of pollution tolerant species. The species that can tolerate low dissolved oxygen levels include-carp, midge larvae, sewage worms (Tubifex), and others. Rever
82、sing the Effects of Cultural EutrophicationAquatic ecosystems have the capacity to recover if the opportunity is provided by:Reducing our use of lawn fertilizers; Encouraging better farming practices; Preserving natural vegetation whenever possible, particularly near shorelines; preserving wetlands
83、to absorb nutrients and maintain water levels; enacting strict ordinances to prevent soil erosion; Supporting measures (including taxes) to improve phosphorus removal by wastewater treatment plants and septic systems; treating storm sewer wastes if necessary; encouraging homeowners along lakes and s
84、treams to invest in community sewer systems; Biological MonitoringYou can determine the toxicity of an effluent or water sample to determine the LD50Ceriodaphnia dubiaDaphnia pulexPimephales promelasStream monitoring: collect samples of organisms and collect data regarding identification and numbers
85、Save Our Streamshttp:/www.vasos.org/pages/gettingstarted.htmlhttp:/www.vasos.org/pages/documents/vasosstandardoperatingprocedures.pdfUsing Insects to Study Stream Health A sample of stream insects, or “macroinvertebrates” is collected, identified and counted.http:/www.vasos.org/ModifiedBugIDCardoct2
86、004.pdfSensitive Insects# Types x 3caddisfly larvahellgrammitemayfly nymphgilled snailsriffle beetle adultstonefly nymphwater penny larvaSomewhat Sensitive Insects# Types x 2beetle larvaclamscrane fly larvacrayfishdamselfly nymphdragonfly nymphscudssowbugsfishfly larva alderfly larvablackfly larvaat
87、herixVery Tolerant Organisms# Types x 1aquatic wormspouch (& other) snailsleechesmidge larvaThe Quality Rating ScaleWATER QUALITY RATINGExcellent (22)Good (17-22)Fair (11-16) Poor (11) What about groundwater?Groundwater pollution caused by human activities usually falls into one of two categories: p
88、oint-source pollution and nonpoint-source pollution. Point-source contamination originates from a single tank, disposal site, or facility. Industrial waste disposal sites, accidental spills, leaking gasoline storage tanks, and dumps or landfills are examples of point sources. Non-point Source Ground
89、water ContaminationChemicals used in agriculture, such as fertilizers, pesticides, and herbicides are examples of nonpoint-source pollution because they are spread out across wide areas. Runoff from urban areas is a nonpoint source of pollution. Because nonpoint-source substances are used over large
90、 areas, they collectively can have a larger impact on the general quality of water in an aquifer than do point sources, Fig. 21-8, p. 502AquiferWater wellMigrating vapor phaseContaminant plume moveswith the groundwaterFree gasolinedissolves ingroundwater(dissolved phase)GroundwaterflowWatertableGaso
91、lineleakage plume(liquid phase)LeakingtankBedrockContamination can move!Groundwater tends to move very slowly and with little turbulence, dilution, or mixing. Therefore, once contaminants reach groundwater, they tend to form a concentrated plume that flows along with groundwater. Despite the slow mo
92、vement of contamination through an aquifer, groundwater pollution often goes undetected for years, and as a result can spread over a large area. One chlorinated solvent plume in Arizona, for instance, is 0.8 kilometers (0.5 miles) wide and several km long!Groundwater MigrationGroundwater migration m
93、odels use hydrology, geology and soil science to predict the flow of the aquifer and the subsequent contamination. Methods are very complex.Computer based models are used to predict the potential reach of the contaminated plume.Groundwater LawsThe two major federal laws that focus on remediating gro
94、undwater contamination include the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also known as Superfund. Groundwater Laws: RCRA and CERCLARCRA regulates storage, transportation, treatment, and disposal of solid
95、and hazardous wastes, and emphasizes prevention of releases through management standards in addition to other waste management activities. CERCLA regulates the cleanup of abandoned waste sites or operating facilities that have contaminated soil or groundwater. CERCLA was amended in 1986 to include p
96、rovisions authorizing citizens to sue violators of the law.Groundwater Clean-upThe EPA decides who is responsible for the clean-up process and monitors progress. ContainmentRemovalBioremediationTreatmentOcean Pollution80 percent of pollution to the marine environment comes from land-based sources, s
97、uch as runoff pollution. Runoff pollution includes many small sources, like septic tanks, cars, trucks and boats, plus larger sources, such as farms, ranches and forest areas.NOAAs RoleThe Commerce Departments National Oceanic and Atmospheric Administration (NOAA) works with the Environmental Protec
98、tion Agency, Department of Agriculture and other federal and state agencies to develop ways to control runoff pollution. NOAAs Coastal Zone Management Program is helping to create special non-point source pollution control plans for each participating coastal state. When runoff pollution does cause
99、problems, NOAA scientists help track down the exact causes and find solutions.Fig. 21-10, p. 505Healthy zoneClear, oxygen-richwaters promote growthof plankton and sea grasses,and support fish.Oxygen-depleted zoneSedimentation and algaeovergrowth reduce sunlight,kill beneficial sea grasses, useup oxy
100、gen, and degrade habitat.Red tidesExcess nitrogen causesexplosive growth of toxicmicroscopic algae,poisoning fish andmarine mammals.FarmsRunoff of pesticides, manure, and fertilizers adds toxins and excess nitrogen and phosphorus.Toxic sedimentsChemicals and toxic metals contaminate shellfish beds,
101、kill spawning fish, andaccumulate in the tissues of bottom feeders.Construction sitesSediments are washed intowaterways, choking fish and plants, clouding waters, and blocking sunlight.Urban sprawlBacteria and viruses fromsewers and septic tanks contaminate shellfish bedsOxygen-depletedzoneClosedbea
102、chCitiesToxic metals and oil from streets and parking lots pollute waters; IndustryNitrogen oxidesfrom autos andsmokestacks,toxic chemicals,and heavy metals in effluents flow into bays and estuaries.Closedshellfish bedsThe LawThe Ocean Dumping Act has two basic aims: to regulate intentional ocean di
103、sposal of materials, and to authorize related research. Title I of the Marine Protection, Research, and Sanctuaries Act of 1972, contains permit and enforcement provisions for ocean dumping. Research provisions are contained in Title II, concerning general and ocean disposal research; Title IV, whic
104、h established a regional marine research program; and Title V, which addresses coastal water quality monitoring. The third title of the MPRSA, authorizes the establishment of marine sanctuaries. SolutionsDilution is NOT the solution to pollution!Even though it rhymes!Fig. 21-18, p. 517 Prevent groun
105、dwater contaminationSolutionsWater Pollution Reduce birth rates Reduce poverty Reduce air pollution Practice four Rs of resource use (refuse, reduce, recycle, reuse) Work with nature to treat sewage Find substitutes for toxic pollutants Reuse treated wastewater for irrigation Reduce nonpoint runoffF
106、ig. 21-9, p. 504SolutionsGroundwater PollutionCleanupPreventionFind substitutes for toxic chemicalsInstall monitoring wells near landfills and underground tanksRequire leak detectors on underground tanksBan hazardous waste disposal in landfills and injection wellsStore harmful liquids in aboveground
107、 tanks with leak detection and collection systemsPump to surface, clean, and return to aquifer (very expensive)Pump nanoparticles of inorganic compounds to remove pollutants (may be the cheapest, easiest, and most effective method but is still being developed)Keep toxic chemicals out of the environm
108、entInject microorganisms to clean up contamination (less expensive but still costly) Fig. 21-14, p. 509Reduce input of toxic pollutantsSolutionsCoastal Water PollutionPreventionCleanupUse wetlands, solar-aquatic, or other methods to treat sewageRequire at least secondary treatment of coastal sewageS
109、prinkle nanoparticles over an oil or sewage spill to dissolve the oil or sewage without creating harmful by-products(still under development)Improve oil-spill cleanup capabilitiesRecycle used oilRegulate coastal developmentProtect sensitive areas from development, oil drilling, and oil shippingBan o
110、cean dumping of sludge and hazardous dredged materialBan dumping of wastes and sewage by maritime and cruise ships in coastal watersSeparate sewage and storm linesRequire double hulls for oil tankersFig. 21-19, p. 517What Can You Do?Water Pollution Fertilize garden and yard plants with manure or com
111、post instead of commercial inorganic fertilizer. Minimize your use of pesticides. Do not apply fertilizer or pesticides near a body of water. Grow or buy organic foods. Do not drink bottled water unless tests show that your tap water is contaminated. Merely refill and reuse plastic bottles with tap
112、water. Compost your food wastes. Do not use water fresheners in toilets. Do not flush unwanted medicines down the toilet. Do not pour pesticides, paints, solvents, oil, antifreeze, or other products containing harmful chemicals down the drain or onto the ground.OCEAN POLLUTIONOceans, if they are not
113、 overloaded, can disperse and break down large quantities of degradable pollutants.Pollution of coastal waters near heavily populated areas is a serious problem.About 40% of the worlds population lives near on or near the coast.The EPA has classified 4 of 5 estuaries as threatened or impaired.Fig. 2
114、1-10, p. 505Healthy zoneClear, oxygen-richwaters promote growthof plankton and sea grasses,and support fish.Oxygen-depleted zoneSedimentation and algaeovergrowth reduce sunlight,kill beneficial sea grasses, useup oxygen, and degrade habitat.Red tidesExcess nitrogen causesexplosive growth of toxicmic
115、roscopic algae,poisoning fish andmarine mammals.FarmsRunoff of pesticides, manure, and fertilizers adds toxins and excess nitrogen and phosphorus.Toxic sedimentsChemicals and toxic metals contaminate shellfish beds, kill spawning fish, andaccumulate in the tissues of bottom feeders.Construction site
116、sSediments are washed intowaterways, choking fish and plants, clouding waters, and blocking sunlight.Urban sprawlBacteria and viruses fromsewers and septic tanks contaminate shellfish bedsOxygen-depletedzoneClosedbeachCitiesToxic metals and oil from streets and parking lots pollute waters; IndustryN
117、itrogen oxidesfrom autos andsmokestacks,toxic chemicals,and heavy metals in effluents flow into bays and estuaries.Closedshellfish bedsOCEAN POLLUTIONHarmful algal blooms (HAB) are caused by explosive growth of harmful algae from sewage and agricultural runoff.Figure 21-11Figure 21-11Oxygen Depletio
118、n in the Northern Gulf of MexicoA large zone of oxygen-depleted water forms for half of the year in the Gulf of Mexico as a result of HAB.Figure 21-AFigure 21-ACase Study: The Chesapeake Bay An Estuary in TroublePollutants from six states contaminate the shallow estuary, but cooperative efforts have
119、 reduced some of the pollution inputs.Figure 21-12Figure 21-12OCEAN OIL POLLUTIONMost ocean oil pollution comes from human activities on land.Studies have shown it takes about 3 years for many forms of marine life to recover from large amounts of crude oil (oil directly from ground).Recovery from ex
120、posure to refined oil (fuel oil, gasoline, etc) can take 10-20 years for marine life to recover.OCEAN OIL POLLUTIONTanker accidents and blowouts at offshore drilling rigs can be extremely devastating to marine life (especially diving birds, left).Figure 21-13Figure 21-13Fig. 21-14, p. 509Reduce inpu
121、t of toxic pollutantsSolutionsCoastal Water PollutionPreventionCleanupUse wetlands, solar-aquatic, or other methods to treat sewageRequire at least secondary treatment of coastal sewageSprinkle nanoparticles over an oil or sewage spill to dissolve the oil or sewage without creating harmful by-produc
122、ts(still under development)Improve oil-spill cleanup capabilitiesRecycle used oilRegulate coastal developmentProtect sensitive areas from development, oil drilling, and oil shippingBan ocean dumping of sludge and hazardous dredged materialBan dumping of wastes and sewage by maritime and cruise ships in coastal watersSeparate sewage and storm linesRequire double hulls for oil tankers
