540 likes | 746 Views
Chapter 21. http://news.yahoo.com/s/ap/20051123/ap_on_re_as/china_water_panic. Water & Soil Pollution. Types of Water Pollution. Sewage Disease-causing agents Sediment pollution Inorganic chemicals Radioactive substances Thermal pollution. Eutrophication.
E N D
Chapter 21 http://news.yahoo.com/s/ap/20051123/ap_on_re_as/china_water_panic Water & Soil Pollution SACCONE POWERPOINT
Types of Water Pollution Sewage Disease-causing agents Sediment pollution Inorganic chemicals Radioactive substances Thermal pollution SACCONE POWERPOINT
Eutrophication Nutrient enrichment of a standing water ecosystem Ex: Lake Washington & Oscillatoria SACCONE POWERPOINT
Eutrophication SACCONE POWERPOINT
Carrying Capacity ( K ) • Exponential growth slows as carrying capacity is reached. SACCONE POWERPOINT
Eutrophication Oscillatoria reached it’s (K). As dead and dying cells rot decomposers consume them and use up the oxygen. BOD or biological oxygen demand increases and life is choked out (hypoxia). SACCONE POWERPOINT
H2O, sunlight, carbonate CO3, N, P, & other inorganic compounds are the main requirements for algal growth (limiting factors). Limit the P and even the N to slow eutrophication. Controlling Artificial Eutrophication SACCONE POWERPOINT
Organic Compounds • Polychlorinated Biphenyls (PCB’s), Benzene, Chloroform, Dioxins, & Vinyl Chloride are examples that can be found in polluted water. SACCONE POWERPOINT
Lead (Pb) • Pb based paint was banned (for sale) in the U.S. in 1978. • Pb additives were removed from U.S. gasoline in 1986. • Pb enters the soil & groundwater from incinerator ash that is dumped into landfills. • Pb enters your body via pesticides & fertilizers on produce, canned foods, & dinnerware. • Middle-aged men, pregnant women, & young kids face the greatest threat. SACCONE POWERPOINT
Mercury (Hg) • Liquid at room temp. & can vaporize. • Liquid Gas Precipitation Contaminates Water • Coal-fired power plants release the largest amount of Hg (33%). • Technology is there to remove the Hg out of coal emissions but it is expen$ive. • Municipal incinerators medical waste incinerators contribute as well. http://www.pca.state.mn.us/programs/mercury-free/ SACCONE POWERPOINT
Mercury (Hg) • Bacteria convert the Hg in the sediments to methyl mercury. These compounds are highly toxic & remain in the environment for long periods of time. • They accumulate into organisms found at the top of the food chain. Tuna, Shark, Swordfish, &marine mammals. • 40 out of 50 states have released health advisories on Hg tainted seafood. SACCONE POWERPOINT
Algal blooms due to marine algae. These can produce toxins that directly kill fish, & cormorants & work their way up the food chain to marine mammals (Monk seals) & people. Cause? Increasing temp? Coastal Pollution? Red Tides SACCONE POWERPOINT
Red Tides SACCONE POWERPOINT
“Dead Zone” in the Gulf Of Mexico • Fertilizers flow from the mighty Mississippi into the Gulf of Mexico from Iowa, Wisconsin, & Illinois (31 states) every spring & summer. • This Dead Zone causes Hypoxia and creates an area of no life the size of New Jersey. Poses a serious threat to commercial fishing in the area. SACCONE POWERPOINT
Radioactive Substances • These isotopes emit radiation. • Originate from mining of Uranium & Thorium, nuclear plants and medical & scientific research facilities, & Radon in the earth’s crust. • 12 sewage treatment plants have tested positive for low level radiation in the U.S. since the 1980’s. SACCONE POWERPOINT
Thermal Pollution • Water is used to cool industrial plants (steam generated electric power plants) & is returned to waterways significantly warmer. • This speeds decomposition and allows less oxygen to dissolve in the water. Fish become stressed, need more food, have to ventilate their gills more and thus have a shorter lifespan. SACCONE POWERPOINT
Sources of Water Pollution Point Source vs. Non-point Source Agriculture Municipal sources Industrial wastes SACCONE POWERPOINT
Sources of Water Pollution Point Source: This is discharged into the environment through pipes, sewers, or ditches from specific sites like factories or sewage treatment plants. Ex: Cyanide spill in Feb. 2000 contaminated the Tisza & Danube Rivers. SACCONE POWERPOINT
Sources of Water Pollution Nonpoint Source: (polluted runoff) is caused by land pollutants that enter bodies of water over broad areas (not a single point.) Precipitation carries pollutants and deposits them into lakes rivers, wetlands, groundwater, & the ocean. Soil erosion is a major source. SACCONE POWERPOINT
Sediment pollution SACCONE POWERPOINT
Sources of Water Pollution Municipal sources contribute urban runoff from storm sewers and city streets. Runoff contains salt, garbage,sediments, & traffic emissions. SACCONE POWERPOINT
Sources of Water Pollution Industrial wastes: Food industries organic wastes Papermills & pulp mills sludge & chlorine Electronics Cu, Pb, Mn, & other heavy metals (can be filtered) SACCONE POWERPOINT
Improving Water Quality • Purification of drinking water through reservoirs (surface water source). • Aluminum sulfate used to take particulates out • Sand used to filter smaller particulates. • Activated carbon used sometimes • Disinfection via Chlorine, O3, or UV radiation. SACCONE POWERPOINT
Water treatment for municipal use SACCONE POWERPOINT
SACCONE POWERPOINT Some pollutants are still detectable at low levels
Improving Water Quality • Municipal Water pollution has a nonpoint source in urban runoff from sewers. • This runoff is often worse than sewage. • It contains asbestos, chlorides, copper, cyanides, grease, hydrocarbons, Pb, motor oil, organic wastes, phosphates, sulfuric acid, and Zn. SACCONE POWERPOINT
Urban Runoff (nonpoint) SACCONE POWERPOINT
Improving Water Quality • Combined sewer systems (NY, San Francisco, Pittsburgh, Boston) mix human & industrial wastes with urban runoff. If too much rain drains into the runoff then the system can’t handle it. • Thus combined sewer overflow flows into waterways without being treated. SACCONE POWERPOINT
Groundwater Pollution • 50% of the U.S. population receives water from this source. • Pesticides, fertilizers, organic compounds, come from landfill seepage, underground storage tanks, backyards, golf courses, & agriculture. • 250,000 petroleum tanks are presently seeping into groundwater (conservative estimate). SACCONE POWERPOINT
Sources of groundwater contamination SACCONE POWERPOINT
Sources of Water Pollution Agriculture: 72% of water pollution comes from agriculture. SACCONE POWERPOINT
Individual Septic Systems • Involve the use of Septic tanks and Leach fields. SACCONE POWERPOINT
Typical septic tank & drainage field system SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Testing Water Pollution SACCONE POWERPOINT
Direction of drainage SACCONE POWERPOINT
Soil Remediation • Alternatives have been developed to stop incineration of contaminated soils including; • Dilution • Vapor extraction • Bioremediation • Phytoremediation SACCONE POWERPOINT
Laws Controlling Water Pollution • Clean Water Act of 1972, 1981, & 1987 • Refuse Act of 1899 SACCONE POWERPOINT
Laws Controlling Water Pollution • Safe Drinking Water Act of 1974 SACCONE POWERPOINT
Dissolved Oxygen SACCONE POWERPOINT