3rd Test Starts Here • Service Opps: today (April 6) – 12:15; bag lunch discussion on UT recycling in UC 224. • Upcoming Clean Air Race April 10: email@example.com • Nashville trip cancelled (we lost again) • Final Exam – last day of our class (April 27) OR assigned day • Service Opp! Big Dig: Summer Intern with Cumberland trail May 16-June 26. Pays $1000.; learn to build & maintain wilderness trails, supervise volunteer trailworkers • Contact: Mark Stanfill at 931-456-6259; www.cumberlandtrail.org
Water Pollution • Water pollution is contamination of water by foreign matter that deteriorates the quality of the water • Normally water can cleanse itself via: dilution, settling, aerosols, biodegradation • Water pollution occurs when these four are overwhelmed • Point vs Non-point sources
Importance: water pollution • Globally, 2.3 billion people suffer from diseases linked to water • Water borne diseases, also known as “dirty water” disease, result from using water contaminated by human, animal, or chemical wastes. These diseases cause an estimated 12 million deaths a year, 5 million of them from diarrheal diseases. Most of the victims are children in developing countries. • According to the World Commission on Water for the 21st Century, more than half of the World’s major rivers are so depleted and polluted that they endanger human health and poison surrounding ecosystem. • In many large cities in the developing world the drinking water supply is contaminated. Only half of Southeast Asia’s 550 million people have access to safe drinking water
Eutrophication • Eutrophication = literally, too much food • Occurs when sewage and/or fertilizer drains into a water body (esp ponds, lakes) • Causes rapid growth of algae (“blooms”) • Algae die and decay uses up oxygen • Causes fish kill; becomes “scummy”
Aerial view of Lake 227 in 1994. Note the bright green color caused by algae stimulated by the experimental addition of phosphorus for the 26th consecutive year. Lake 305 in the background is unfertilized
Mitigating eutrophication • What Can I Do? • Limit your fertilizer use and apply at appropriate times (UMD's Home and Garden Information Center) • "BayScape" your yard (Alliance for the Chesapeake Bay) • Control runoff and soil erosion (UMD's Home and Garden Information Center). • Start a compost pile and recycle yard waste (UMD's Home and Garden Information Center). • Conserve water and energy (Maryland Department of Natural Resources) • Plant trees (Maryland Department of Natural Resources). • Maintain your septic system (University of Maryland) • Drive less • Be a responsible boater and pump out wastes
Fixing (restoring) water bodies • 1) Stop point pollution – factories, pipes (pretty easy) • 2) Stop non-point pollution-very hard; build artificial wetlands: retention ponds with lots of cat-tails and other vegetation (slow water down, trickle into river or lake) • 3) For ponds: drain and dredge; aerate • 4) Restock with native fishs and plants • Lake Erie is recovering; Lake Apopka Fla • Rivers & creeks can recover quickly if pollution stopped and river channel renaturalized
Water quality testing • DO (Dissolved Oxygen) • Nitrates, phosphates • E. coli (coliform bacteria) – culture kits • Sediment (turbidity) • IBI – Index Biotic Integrity: is aquatic diversity low? Are a few species superabundant? If yes: unhealthy stream • Indicator species: trout, most clams, stream minnows = healthy stream • many insect larvae, protozoans, exotic species (carp, zebra mussel)= unhealthy stream.
EPA primary regs • List of Contaminants regulated by EPA: Microorganisms | Disinfectants | Disinfection Byproducts | Inorganic Chemicals | Organic Chemicals | Radionuclides • MCL’s for all of these are tested, periodically by law, especially in water systems
EPA secondary regs • National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA recommends secondary standards to water systems but does not require systems to comply. However, states may choose to adopt them as enforceable standards.
Oxidation ditch Clarifier
Wastewater treatment • The chemicals used in the waste purification process can also be harmful. Used in large quantities, these chemicals – including chlorine or chlorine dioxide gas -- can produce environmental risks. Storm water run-off might also pose a problem if contaminated with waste or other pollutants. The often foul smell of sewage treatment plants can generally be attributed to hydrogen sulfide, which is toxic and can cause problems ranging from eye irritation and nausea to toxic explosions. However, the odor is often diluted in the air and is usually of little or no harm. • Treatment plants can cause contaminated water. Potential contaminators are bacteria, nitrates, oxygen-depleting organics, and metals. Exposure can occur through drinking such water, direct skin contact, digesting fish from contaminated waters, or even swimming in such waters. Reactions can range from rashes to hepatitis. • Trihalomethanes (THM’s) = carcinogenic byproducts of chlorination. Solution? Ozonation of water.
Tap water problems • Tap Water Is Full Of Disease-Causing Contaminants - Most municipal water flows through lead pipes over 100 years old picking up harmful toxins and pollutants before the water treatment plant (which performs very limited functions) and also afterwards when the water is on its way to your house. • Arsenic - Which has been directly linked to cancer and many other diseases, has been found in 85% of our cities' water. Exposure to lead found at "alarmingly high levels" in many cities by Consumer Reports, can cause learning and behavioral problems in children, lower IQ, high blood pressure, and problems to the reproductive and nervous systems. • Some other common water contaminants and what they have been linked to are: Asbestos (cancer and other diseases), Aluminum (Alzheimer's), Benzene (cancer, anemia), Mercury (nervous system and kidney damage), Toluene (cancer), herbicides and pesticides such as Endrin (liver, kidney and heart damage, respiratory problems and cancer). • 80% of city water systems were not equipped with filters that meet EPA standards. In addition, most cities add the harmful Chlorine and Fluoride to water.
Tap water problems • A recent Water Quality Association poll showed that 74% of Americans consider their tap water contaminated or dangerous. 80% don't like the taste. And the following annual figures from the National Resources Defense Council confirm the shocking problem: Every year in the U.S.: • 900,000 Sick and 900 Dead due to water contamination. • These figures don't even factor in the thousands of long term illnesses and deaths from cancer, kidney and heart disease linked to contaminated water. • If you have your own well water, you're not really better off. In fact, most of those on well water have more contaminants per drop than those in cities. • Many are also concerned today by bio-terrorism threat to our water supplies as there are 168,000 different public water supplies in the U.S., many of which are completely unprotected.
Bottled water • Bottled Water May Be Worse - Recognizing the problem with tap water, many Americans have turned to bottled water. Unfortunately, bottled water is not only quite expensive, it is often just as contaminated as your tap water. • According to FDA rules, bottled water is subject to less testing and lower standards than our tap water! Even disinfection is not a requirement for bottled water! A 4-year NRDC scientific study on bottled water, based on 1000 bottles of 103 brands of water confirmed that bottled water is not necessarily cleaner or safer than common tap water. • University of Iowa tested 39 different brands of bottled water and found that 75% of them contained chemicals, dissolved metals, and traces of arsenic, barium and toluene. Their conclusion was "Bottled water is no better than tap water and, in some cases, even worse".
Low pressure units typically provide between 24 and 35 gallons per day of water They typically filter up to 95% of the material in the water.
Legal Aspects I • Riparian law = landowner water rights • Appropriation law = government water rights • Both often fail to protect downstream users • Example: rule of “prior use” out West: big mess (Colorado River) • Example: private law suits to collect damages in your water
Legal Aspects II • Clean Water Act 1972: point sources largely fixed • Safe Drinking Water Act 1974: water supply regulated • Unfixed problems: non-point runoff and ground water pollution (mostly state laws; very weak in TN)
Announcements • Exam April 27 or during finals week • Service opps: • UT EarthDay April 22: contact Christina at firstname.lastname@example.org • April 14 – see Lois Gibbs talk (Love Canal story) 7 pm UC auditorium; also 2-4 pm workshop on activism in Physics 306
Air Pollution • When air composition is altered to the point that harm occurs (to human health or property) • Air composition: 78% N, 21% O = 99% • N2 is an inert (nonreactive) gas • Remaining 1% includes hundreds of kinds of gases and particles (CO2, CH4, dust, water vapor); usu measured as ppm, ppb • All air pollution is in this remaining 1%
Importance of Air Pollution • Health: bad air costs US over $150 billion per year (medical, lost work days), kills over 10,000 people per year (how?who?) • Most dangerous in US: indoor air pollution (stealth problem) is no. 1; also smog is v. imp. • Ecological harm: ozone layer loss, global warming, acid rain, smog on plants • Property harm: erosion of buildings
Kinds of air pollution • Lots of human activities increase air pollution (anthropogenic sources) – most come from fossil fuel combustion • 1) particulates (unburned ash) – mostly in poor nations – in US 99% filtered out by scrubbers in smokestacks; causes lung damage • 2) carbon oxides (CO, CO2) - esp from motor vehicles: CO is odorless, colorless gas. CO2 is main cause of global warming
Kinds of air pollution (cont.) • 3) Sulfur oxides (SOx) – from coal burning, H2O + SOx = H2SO4 (sulfuric acid). • Creates acid rain. pH scale goes from 0-14, > 7 = alkaline; < 7 = acidic. Log scale. Natural rain is mildly acid (around 6). Acid rain < 5.6. Record in Smokies < 1. • Result: acid lakes impacts trout, acid soils kills trees.
Effects of acid rain on statue Statue in a makeshift shelterto save it from acid rain in Berlin Germany
statue in Germany. The photo on the left was taken in 1908 and the one on the right was taken in 1969.
Kinds of air pollution (cont) • 4) smog = NOx + VOCs + O3 + light • NOxVille, Tennessee • This is a photochemical reaction. • Most damaging air poll to our health • Effect: burns lung tissue, eyes • Sources? 140,000 cars/trucks on I-40 daily • Time of day smog peaks?
Bad air rankings Cities and counties with the worst ozone air pollution, based on U.S. Environmental Protection Agency monitoring in 1997-1999, according to "State of the Air 2001" report by the American Lung Association released Tuesday. Previous year rankings are in brackets. • Los Angeles, Calif. (1) • Bakersfield, Calif. (2) • Fresno, Calif. (3) • Visalia, Calf. (4) • Houston, Texas (5) • Atlanta, Ga. (9) • Washington, D.C.(7) • Charlotte, N.C., Rock Hill, S.C. (8) • Knoxville, Tenn. (12) • Philadelphia, Pa., Atlantic City, N.J. (13) • Raleigh, Durham, Chapel Hill, N.C. (17) • Sacramento, Calif. (10) • Merced, Calif. (10) • Dallas, Texas (14) • New York, N.Y.; (16) • Nashville, Tenn. (18)
The above photo shows a long line of cars lined up to enter Great Smoky National Park. Aside from the smog blown in from distant power plants and urban areas, the exhaust from the cars of an average of 10,000,000 visitors each year doesn't help the severe air pollution problem in Great Smoky National Park, either. On 140 days during the past four years, the National Park Service has had to warn employees and park visitorsthat the air in the park was unhealthy because of high levels of smog
GSMNP same view, With and w/out smog
Solutions to air pollution • Clean Air Act 1970 reduced many sources BUT many loopholes remain: • Grandfathered power plants (TVA) • Clunker cars (before 1985 esp) • Trucks & SUVs, Semi-trucks exempt from much of it • Small engines: boats, mowers, leaf blower • TN phased out mandatory inspections!
Indoor air pollution • Overlooked but most harmful. Why: spend 80% indoors, poll is concentrated • Main kinds: cig smoke (incl 2nd hand); radon, toxic chems from carpet, furniture, household chems • SBS = sick building syndrome
Global Air Pollution • Loss of the ozone layer – 20 miles up protects life from ultra-violet radiation • How made? Light + 3O22O3+CFC CFC is a catalyst that accelerates the return of O3 back to O2
CFCs • CFC = chlorofluorocarbons, invented 1931 • Since then, 36 billion pounds produced in US • Very inert; used as refrigerant (freon), cleaning fluid, aerosol propellant (why?) • So lasts many decades in air w/out breaking down • In 1970’s discovery of “ozone hole” over S. Pole
If we lose the ozone layer: • Blindness • Skin cancer • Fertility loss • Plants dies • Ocean food chain • Eventually cities underground? Matrix movie but probably without Neo
Solutions? • Montreal Protocol (Treaty) of 1987 to phase out CFCs • Production of alternatives: compressed air, HFC’s, HCFC’s etc. • Very successful (why?) • Corporate idiocy? DuPont vs Greenpeace • Remaining problems: continued illegal production and use of CFCs • Takes over 10 yrs to diffuse up to Oz layer