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Chap 11, Sect. 3-Water Pollution. Objectives Compare point-source pollution and nonpoint-source pollution Classify water pollutants by five types Explain why groundwater pollution is difficult to clean up
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Chap 11, Sect. 3-Water Pollution • Objectives • Compare point-source pollution and nonpoint-source pollution • Classify water pollutants by five types • Explain why groundwater pollution is difficult to clean up • Describe the major sources of ocean pollution, and explain the effects of pollution on ecosystems • Describe six major laws designed to improve water quality in the U.S.
DE State Science Standard 8/GLEs GLEs: Evaluate decisions about the use of resources in one country and how these decisions can impact the diversity and stability of ecosystems globally. Analyze ways in which human activity (i.e., producing food, transporting materials, generating energy, disposing of waste, obtaining fresh water, or extracting natural resources) can affect ecosystems and the organisms within Relate a chemical’s properties to its accumulation within organisms, such as PCBs in the fatty tissues of fish. Explain how biomagnification has led to unsafe food supplies, such as mercury accumulation in tuna. Analyze how an understanding of biomagnification has led to the regulation of chemical use and disposal.
Bellringer - Ecolog • Define the termwater pollution • Is a cup of coffee pollutedwater? • Is a muddy stream polluted?
Water Pollution • Water Pollution: The introduction of chemical, physical, or biological agents into water that degrade water quality and adversely affect the organisms that depend on the water. • Two underlying causes of water pollution: Industrialization and rapid human population growth.
Developed vs Developing • Developed Countries: Major cause of water pollution is industrialization • Developing Countries:Major cause of water pollution is sewage and agricultural runoff, spreading diseases.
Point-source Pollution • Point-source Pollution: pollution discharged from a single source. • Examples: leaking septic tank, leaking storage lagoons for polluted waste, unlined landfills, leaking underground storage tanks that contain chemicals or fuels such as gasoline, polluted water from active or abandoned mines, water discharged by industries, public waste-water treatment plants
Non-point-source Pollution • Non-point-Source Pollution: comes from many different sources that are often difficult to identify. • Examples: chemicals added to road surfaces (salt and deicing agents), water runoff from city and suburban streets that may contain oil, gasoline, animal feces, and liter
Non-point-source Examples • Pesticides, herbicides, and fertilizer from residential lawns, golf courses, and farmland • Feces and agricultural chemicals from livestock feedlots • Precipitation containing air pollutants • Soil runoff from farms and construction sites • Oil and gas from personal watercraft
Non-point Pollution Con’t • 96% of all polluted bodies of water in the United States were contaminated by non-point sources • Controlling non-point-source pollution depends to a great extent on publicawareness of the effects of activities such as spraying lawn chemicals and using storm drains to dispose of used motor oil
Non-point Pollution Con’t • Two cycle engines (Jet Skis, snowmobiles) are estimated to leak millions of gallons of unburned fuel into ecosystems • 20-25% of fuel in two cycle engines fails to combust, and it flushes into water as raw fuel vapor.
Pollutant Types and Sources • Pathogens: disease causing organisms, such as bacteria, viruses, protozoa, and parasitic worms. • Mostly non-point sources; sewage or animal feces, livestock feedlots, and poultry farms; sewage from overburdened wastewater treatment plants
Pollutant Types and Sources • Organic Matter: animal and plant matter remains. Feces, food waste, and debris from food processing plants • Mostly non-point sources
Pollutant Types and Sources • Organic chemicals: pesticides, fertilizers, plastics, gasoline and oil, and other products made from petroleum • Mostly non-point sources: farms, lawns, golf courses, roads, wastewater, unlined landfills, and leaking underground storage tanks
Pollutant Types and Sources • Inorganic chemicals: acids, bases, salts, and industrial chemicals • Point-sources and non-point sources • Industrial waste, road surfaces, wastewater, and polluted precipitation
Pollutant Types and Sources • Heavy Metals: lead, mercury, cadmium, and arsenic • Point sources and non-point sources • Industrial discharge, unlined landfills, some household chemicals, and mining processes. • Heavy metals can also occur naturally in some groundwater
Pollutant Types and Sources • Physical Agents: heat and suspended solids • Point sources and non-point sources • Heat from industrial processes and suspended solids from soil erosion
Pollutant Sources – U.S. • Point Sources • 23 million septic-tank systems • 190,000 storage lagoons for polluted waste • 9,000 municipal landfills • About 2 million underground storage tanks containing pollutants such as gasoline • Thousands of public and industrial wastewater treatment plants
Pollutant Sources – U.S. • Non-point Sources • Highway construction and maintenance, including eroding soil and toxic chemicals • Storm-water runoff including oil, gasoline, dog feces, and liter from city and suburban streets • Pesticides from cropland • 50 million tons of fertilizer applied to crops, lawns and golf courses every year • 10 million tons of dry salt applied to highways for snow and ice control every year
Dioxins • Dioxin refers to a group of chemicals that contain chlorine, carbon, oxygen, and hydrogen. They are a byproduct of chemical processes such as paper bleaching. • Dioxins may cause liver and nerve damage, genetic, reproductive, and immune system problems, and many other problems • According to the EPA, dioxins are some of the most toxic chemicals known to science, and they are the most dangerous environmental pollutants in North America - • DuPont Edgemoor
Wastewater: water that contains waste from homes and industry Wastewater Treatment Plants filter and treat wastewater to make the water clean enough to return to river or lake Wastewater
Wastewater • Most of the wastewater from homes contains biodegradable material that can broken down by living organisms( animal and plant waste, paper, and soap) • Some household and industrial wastewater and some storm-water runoff contains toxic substances that cannot be removed by standard treatment
Sludge • Sludge: The solid material that remains after treatment. • When sludge contains dangerous concentrations of toxic chemicals, it must be disposed of as hazardous waste • Non-hazardous sludge can be used as fertilizer.
Eutrophication • Eutrophication: when lakes and slow moving streams contain an abundance of nutrients. When organic matter (leaves and animal waste) builds up in a body of water it will begin to decay and decompose. This process of decomposition uses up oxygen. As oxygen is used up, the types of organisms that live in the water change over time
Eutrophication • Plants take root in fertile sediment at the bottom of water. As more plants grow the waters begin to fill in forming a swamp or marsh
Artificial Eutrophication • Eutrophication caused by humans is known as Artificial Eutrophication • Inorganic plant nutrients such as phosphates and nitrogen enter the water from sewage and fertilizer runoff. • Phosphates from laundry detergents can also cause eutrophication
Artificial Eutrophication • Phosphates can cause the growth of large algal blooms,large floating mats of algae. As the algae dies and decompose, most of the dissolved oxygen is used and fish and other organisms suffocate in the oxygen depleted water. ( fish kills)
Thermal Pollution • When the temperature of a body of water increases thermal pollution can result. • As water temperature increases, oxygen levels decrease and can cause massive fish kills • Thermal pollution can occur when power plants and other industries use water in their cooling systems and then discharge the warm water into a lake or stream
Groundwater Pollution • Pollutants usually enter groundwater when polluted water percolates down from the Earth’s surface • Pesticides, herbicides, chemical fertilizers, and petroleum products, as well as leaking underground tanks, are common groundwater pollutants • Other sources include: septic tanks, unlined landfills, and industrial waste lagoons
ppm –(parts per million) • Parts per million water contamination is usually measured in parts per million (ppm) • If the concentration of a pollutant is 5 ppm, there are 5 parts of the pollutant in 1 million parts of water. • If the concentration of gasoline is 3 ppm in 650,000 L of water, how many liters of gasoline are in the water?
ppm solution • (3/1,000,000) x 650,000 L = 1.95 L
Groundwater Clean-up • Groundwater pollution is world’s most challenging environmental problem • Even if groundwater pollution were stopped tomorrow, some ground water would remain for generations to come. • Groundwater recharges are very slow, sometimes taking hundreds to thousands of years
Ocean Pollution • Approximately 85% of ocean pollution, including oil, toxic wastes, and medical wastes, come from activities on land • Most activities that pollute oceans occur near the coasts, where much of the world’s population lives • Sensitive coastal ecosystems (coral reefs, estuaries, and coastal marshes) are most effected by pollution
Eco-Fact • Cruise Ship Discharges • In one year, ships dump almost 7 billion kg of trash into the oceans, about 75% from cruise ships • According to most international law, cruise ships are allowed to dump non-plastic waste, including untreated sewage into the oceans
Oil Spills • Each year approximately 37 million gallons of oil from tanker accidents is spilled into the oceans • Tanker oil spills only account for about 5% of oil pollution in the oceans • Most of the oil that pollutes the oceans comes from cities and towns
Oil Spills • Every year, as many as 200 million to 300 million gallons of oil enter the ocean from no-point sources on land • That’s almost 10 times the amount of oil spilled by tankers • The road runoff from a coastal city with a population of 5 million in one year could contain as much as a tanker spill
Water Pollution and Ecosystems • Many pollutants accumulate in the environment because they do not decompose quickly • Biomagnification: Each organism along the food chain stores store pollutants in their tissue. So, at each level of the food chain, the level of pollutants increases. • Top of food chain accumulates most toxins
Anti-Pollution Legislation • In 1972 the Clean Water Act was passed in the United States. • The stated purpose of the act was to “restore and maintain the chemical, physical, and biological integrity of the nation’s waters” • Goal: to make all surface water clean enough for swimming and fishing by 1983
Anti-Pollution Legislation • This goal was not achieved. The percentage of lakes and rivers that are fit for swimming and fishing has increased by 30% • Many toxic metals are now removed from wastewater before the water is discharged
Anti-Pollution Legislation • 1972: Clean Water Act: goal of making all surface water safe for swimming and fishing by 1983 – 30% achieved • 1972 (Amended 1988)Marine Protection, Research, and Sanctuaries Act: Empowered the EPA to control the dumping of sewage and toxic chemicals in U.S. waters
Anti-Pollution Legislation • 1975: Safe Drinking Water Act: (Amended 1996): introduced programs to protect groundwater and surface water from pollution, strengthened public “right-to know” laws
Anti-Pollution Legislation • 1980: Comprehensive Environmental Response Compensation and Liability Act ( Superfund act): Makes owners, operators, and customers of hazardous waste sites responsible for the cleanup of the sites
Anti-Pollution Legislation • 1987: Water Quality Act: Supported state and local efforts to clean polluted runoff. Established loan funds for new wastewater treatment plants, and created programs to protect major estuaries
Anti-Pollution Legislation • 1990: Oil Pollution Act: Attempts to protect U.S. waterways from oil pollution by requiring that oil tankers in U.S. waters be double-hulled by 2015.