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Water Pollution. Sources. Two Types: Point sources and nonpoint sources Ex: Point: sewage plants; nonpoint: runoff Examples of sources: Chemicals (metals, solvents, oils) Air pollution Microbiological sources Mining Noise Nutrients Oil spills
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Sources • Two Types: Point sources and nonpoint sources • Ex: Point: sewage plants; nonpoint: runoff • Examples of sources: • Chemicals (metals, solvents, oils) • Air pollution • Microbiological sources • Mining • Noise • Nutrients • Oil spills • Oxygen depleting substances (biodegradable) • Suspended matter • Thermal sources • hormones
Water Quality 1. Cultural Eutrophication: the process by which human activity increases the amount of nutrients entering surface water. (nitrogen and phosphorus) nutrients= algae = DEAD ZONES (oligotrophic = low nutrients Eutrophic= high nutrients) 2. Tests to monitor water quality: • Nitrogen (Fertilizers) • Chlorine (disinfects) • Hardness (usually caused by calcium and magnesium) • Copper (fertilizers, septic tanks and industrial waste) • DO (dissolved oxygen) flowing = increase (closer to surface) • Phosphate: fertilizers • pH: needs to be close to 7 3. EPA Standards • Primary: health concerns • Secondary: aesthetics
We will be testing water on Friday. If you have water you want to test. Bring it and we will test it • Awesome Video
Effects • Infectious diseases • Chronic: slowly impairs the function • Acute: rapidly impairs function • Spread of disease: epidemic vs. pandemic • Epidemic: rapid increase of a disease • Pandemic: the disease spreads to other places • Toxicology: study of harmful chemicals • Neurotoxins- disrupt the nervous system ( lead and mercury) • Carcinogens: cause cancer (radon, formaldehyde) • Teratogens: interfere with embryo development • Allergens: cause an allergic reaction (not pathogens) • Endocrine disruptors: interfere with normal hormone function (cleaning products and household goods) • Biomagnification: the increase of a chemical in animal tissues as it moves up the food chanin.
What can be done? • Water treatment • Septic Tanks: two parts- septic tank and leach field. • Sewage treatment plant: • Primary (reduces oils, includes sand catchers, screens, and sedimentation) • Secondary (gets rid of the biological content) includes: filters, activated sludge, filter (oxidizing) beds, trickling filter beds, and secondary sedimentation. • tertiary treatments(final stage before releasing into the environment. May include: filtration, lagooning, constructed wetlands, nutrient removal through biological or chemical precipitation, denitrificationusing bacteria, phosphorous removal using bacteria, microfilration and disinfection using UV, chlorine or ozone.
Treatment Methods and remediation technologies • Adsorption • Disinfection • Filtration • Flocculation • Ion Exchange • Aeration • Air stripping • Bioreactors • Constructed wetlands • Deep-well injections • Enhanced bioremediation • Fluid-vapor extraction • Granulated activated carbon • Hot water flushing • In-well air stripping • phytoremediation • UV oxidation
Legislation • Stockholm Convention: (2001): a group of 127 countries gathered in Sweden. 12 chemicals were banned, phased out or reduced. (the “the dirty dozen”) • Clean Water Act: (1972) issued water quality standards that defined acceptable limits of various pollutants in US waterways. (Surface water not ground water) • Safe Drinking Water Act: (1974, 1986, 1996) sets the national standards for safe drinking water. (MCL: maximum contaminant levels)
Noise Pollution • Causes: Human created sound that disrupts the environment. (transportation, factories, appliances, audio entertainment systems) • Health Effects: hearing loss, cardiovascular problems, decrease in ability to memorize, nervousness, pupil dilation, decrease in visual field, insomnia, bulimia, high blood pressure, depression, anxiety, and sexual dysfunction. • Control: noise barriers (trees) and new technologies.
Solid Waste • Types: • Organic: kitchen waste, vegetables, flowers (usually decomposes in 2 wks ** Wood can take up to 10-15 years) • Radioactive: spent fuel rods, smoke detectors (100 of thousands of years) • Recyclable: paper, glass, metals, and some plastics. (paper- 10 days, glass- never, metals- 100-500 years, plastics- some up to 1 million years) • Soiled: hospital waste (cotton cloth-2-5 months) • Toxic: paints, chemicals, pesticides (100’s of years.) • Uses in the US: • Disposal and Reduction Flow Chart
Solid Waste • Choices to disposal: • Burning, incineration or energy recovery • Detoxify • Exporting • Land disposal(land fills) • Land disposal (open dumping) • Ocean dumping • Recycling • Reuse