Chapter 5 –Water Pollution(Hwk#5- pp.146 2,4,5)

•point source .vs. disperse source – confined or localized source .vs. a body of pollutant sources •thermal .vs. enrichment pollution – higher water temperatures due to the additions of pollutant(i.e. some fish flourish at higher temperatures, but higher temperatures decrease water solubility)

Chapter 5 –Water Pollution

•Thermal pollution prevention-Natural draft hyperbolic cooling tower.•Sediments- smothers organisms at bottom of body of water and disrupts reproductive cycles of fish•Soil Erosion – can remove the topsoils or fertile soils from the land, leaving it barren (i.e. disrupts photosynthesis when in water,caused by construction and landuse)

Chapter 5 –Water PollutionNote: Soil Erosion Prevention techniques is found on pp. 126 & 127•Reaeration –oxygen transfer between air and water•plume- a conical distribution of contaminants

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Chapter 5 –Water Pollution

Lake PollutionEutrophication- due to nutrient enrichment a lakebegins to age into a marsh(a natural form of pollution)

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Source of ContaminationIndustrial- TCE, oil spills, impoundment leakageSewage disposal systems – improper design and maintenanceMunicipal landfills-poor or no liner materialMining and Petroleum products- leaky USTs or gasoline stationsAgriculture –Nitrates, Pesticides and fertilizers.Saltwater Intrusion – within drinking water due to excessive well water usage(pp.138)

Chapter 5 –Water PollutionNote: phosphorus in lakes is caused by wastewatereffluents and runoff. Nitrogen and phosphorus enter are introduced from agricultural areas.Methods of prevention:Create streams or interceptor pipelinesIntroduce a specified amount of copper sulfate

Estuaries- are natural transition zone between salt and fresh water (including bays, river mouths, and salt marshes)The ocean depends on Estuaries for NutrientsMultiport diffusers-pp.140 Prevent plumes of sewage from going back to the shore and create uniform distribution and prevents boilOcean dumping of Sludge- Banned by Congress. (i.e. N.Y.C ships sludge by rail to Texas).Oil Spills – Prevented by stricter int’l standards

Chapter 5 –Water PollutionOcean Pollution(3.5% dissolved solids)

Chapter 5 –Water Pollution(Water Quality Standards)

STREAM STANDARDS

TREATED SEWAGE EFFLUENT

DRINKING WATER SUPPLY

CLEAN WATER ACT (1977)Added to the above act a control of priority toxic pollutants.

WATER QUALITY ACT (1965)REQUIRED THAT THE STATES ASSESSED MAXIMUM BENEFIT OFTHEIR STREAMSA. w ater suitable for primary contact B. Water Suitable for Fish C. Water Suitablefor public w ater D.Water suitable for agricultural or industrial use

FEDERAL WATER POLLUTION CONTROL ACT AMENDMENTS (1972)Included permit system for all point source dischargers w hich included effluentdischarges as w ell as stream standards.