Chapter 14 Environmental Science for AP - Friedland and Relyea
Diffuse areas that pollute. Farming region, suburban community with many lawns and septic systems, or storm runoff from parking lots.
Contamination of streams, lakes, oceans, or groundwater with substances produced by humans.
Overnourishment of aquatic ecosystems with plant nutrients (mostly nitrates and phosphates) because of human activities such as agriculture, urbanization, and discharges from industrial plants and sewage treatment plants. This leads to algae blooms shading lower plants from sunlight and decomposition of algae depleting the oxygen to form dead zones where most aquatic life is absent.
Distinct locations like a factory, or a sewage treatment plant.
Waste produced by human activities including human sewage from toilets and gray water.
Oxygen Demanding Waste
Organic matter that enters a body of water and feeds the growth of microbes that are decomposers. Measured in terms of BOD
Biochemical Oxygen Demand. Amount of oxygen a quantity of water uses over a period of time at a specific temperature. Lower is less polluted.
Areas with little oxygen and little life. Can be self-perpetuating with the dying organisms subsequently decomposing and causing continued oxygen demand by microbes.
Decomposition of waste water provides an overabundance of fertility to a water body.
Organism that indicates whether or not disease causing pathogens are likely to be present.
Fecal Coliform bacteria
Generally harmless microorganisms that live in the intestines of human beings and other animals. E. coli. Found in water when human waste is in it.
Composed of a septic tank and a leach field. Found in individual houses in rural areas. Wastewater held in septic tank where solids settle to bottom as sludge, middle layer is fairly clear water called septage, and floating stuff forms scum layer. Septage moves out of septic tank by gravity into several underground pipes laid out across a lawn below the surface called leach field. Then filtered by soil.
Sewage Treatment Plant System
Underground pipes carry waste to treatment plants. Large debris filtered out by screens and sent to landfill. Solid Waste/sludge settles to bottom of tank. Bacteria break down organic material to CO2 and inorganic nutrients and settled particles added to sludge. Sludge thickened by removing water. Thickened sludge taken to landfill, burned, or used for fertilizer. Exposure to chemicals or UV light kills pathogens. Treated water released into river or lake.
Large, human-made ponds lined with rubber to prevent manure from leaking into groundwater. Leaks could greatly contaminate.
Naturally in crust and can dissolve into groundwater, humans breaking up rocks also contributes.
NOx and SO2 convert to sulfuric and nitric acids in atmosphere. React and bond with rain and fall with it. Increased pH can be lethal to some aquatic organisms.
Flame retardants. Can lead to brain damage, been found in fish, birds, and human breast milk. More research needed.
Oil Spill Cleanup Methods
For surface oil, contain oil within one area with plastic barriers and suck off surface. Apply chemicals that help break up the oil making it disperse before it hits shoreline, but chemicals could be toxic to marine life. Tides naturally remove from beaches but oil remaining in rocky crevices will have negative effects. No agreed upon method for cleaning up underwater plumes.
When human activities cause a substantial change in the temperature of water.
Many species die because a dramatic change in temperature puts them outside their natural range of temps.
Clean Water Act
Maintains and restores the chemical, physical, and biological properties of natural waters.
Maximum Containment Levels
Max level of one of 77 substances that can exist in a body of water.
Leading causes and sources of pollutants for streams and rivers
Bacterial pathogens, habitat alteration, oxygen depletion. Agriculture, water diversions, dam construction.
Leading causes and sources of pollutants for Lakes, ponds, and reservoirs
Leading causes and sources of pollutants for bays and estuaries
Bacterial pathogens, oxygen depletion, mercury.
Atmospheric deposition, municipal discharges including sewage.
Chesapeake Bay Watershed
- Largest estuary in the United States
Safe Drinking Water Act
(SDWA, 1974) set maximum contaminant levels for pollutants in drinking water that may have adverse effects on human health
The ground area around a septic tank through which waste waters filters after leaving the tank.
Heavy metal pollution
Such as mercury and lead, can cause various health problems and bio magnify in the aquatic food web.
Oxygen Sag Curve
The curve obtained when the concentration of dissolved oxygen in a river into which sewage or some other pollutant has been discharged is plotted against the distance downstream from the sewage outlet (see graph). Samples of water are taken at areas upstream and downstream from the sewage outlet.
Flint Michigan Water Crisis
Treated water supply switched to Flint river which is more acidic and thus more corrosive to lead pipes. High levels of lead end up in drinking water. Lead contamination has severe health effects on elderly and children including rashes, infections and impairments to the development of brain and nervous system.
National Pollutant Discharge Elimination System Limits the amount of effluents discharged into the USA's waterways.
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