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WATER Outline • Water pollution enforcement (before test) • Sources –Categories of pollution (before test) • Effects –Result of pollution in water (after test) Environmental Issue • Problems that affect some part of the Earth, usually a result of people or their actions – Water, air, soil, food, waste, plants • Water as an environmental issue – Quality – how clean is it? – Quantity – how much is there? Water pollution • Pollutant: any waste discharged into water, including materials, equipments, rock, spoil, sewage, garbage, etc. – Heated water above the temperature of the receiving water also a pollutant 1 Terminology • Point source pollution: “any discernable, confined, and discrete conveyance”, such as pipes or man made ditches that discharge pollutants into water • Nonpoint source pollution: caused by rainfall or snowmelt moving over and through the ground. – Includes atmospheric deposition – contaminants carried by air Nonpoint source pollution 4 categories of NPS pollution 1. Agriculture runoff – Pesticides and fertilizers – Example: cows produce 66lbs of manure/day • Feedlots not necessarily required to control, treat, or capture runoff 2. Urban runoff: streets, parking lots, golf courses, gardens, industrial sites 3. Construction Sites: release vast amount of sediments in water 4. Land disposal: waste, dumps, septic systems Cleaning up the waters • 1899 Rivers and Harbors Act – navigable waters • 1948 Federal Water Pollution Control Act – Control water pollution through state-led efforts – Enforcement left to governors (states) 2 Events leading up to new regulation • • • • • Cuyahoga River Fire (1969) Santa Barbara, CA oil spill (1969) EPA founded 1970 Earth Day 1970 Water Wasteland (Ralph Nadar) -1971 Cuyahoga River, 1936 State of water in early 1970s • 1966-1968: 26 million fish killed in Florida due to food-processing plant discharge • 1969: Hudson River had 170x the safe level of bacteria • 1970: 30% of drinking water samples exceeded recommended chemical limits • 1971: 85+% swordfish contained mercury exceeding safe limits Clean Water Act - 1972 • Amendment to the Federal Water Pollution Control act • Changed in philosophy to “clean waters” • Uniform technology-based standards • Goals to eliminate pollution • Protect fish, wildlife, and recreational use • Shifted permitting and enforcement from states to federal government - EPA 3 NPDES and CWA additions • National Pollutant Discharge Elimination System (NPDES) – issues all permits for discharges of allowable levels of pollutants into waters – Generally does not issue permit for discharges into municipal water sewer system • EPA • Water Quality Acts of 1985 and 1987 – sets goals for swimmable quality and storm water discharge Other important water regulations • Ports and Waterways Safety Act – 1972regulates oil transport and oil handling facility operation • Safe Drinking Water Act – 1974 – requires minimum drinking standards for every community – Bacteria, nitrates, arsenic, cadmium, chromium, lead, mercury, silver, radioactivity, barium • London Dumping Convention – 1990 – calls for end of ocean dumping of waste and trash Storm water discharge • Water Quality Act of 1987 – require industries and municipalities to have permits for discharges of stormwater runoff to control nonpoint source pollution – Storm water can carry sediment, chemicals, hazardous wastes, debris (Ben Raines/Press-Register) 4 State of water today • Large-scale success • Some water still not drinkable, swimmable, nor should fish be consumed from it • Last EPA report (2002): 40% streams, 45% lakes, 50% estuaries too polluted – From bacteria, nutrients, metals, sewage – Cause: urban runoff, sewage, agricultural runoff Categories of water pollution Category Examples Sources A. Causes Health Problems Infectious agents Bacteria, viruses, Human and animals parasites Organic chemicals Pesticides, plastics, Industrial, household, detergents, oil, & and farm use gasoline Inorganic chemicals Acids, caustics, Industrial, household salts, metals cleaners, surface runoff Radioactive materials Uranium, thorium, Mining and processing production, natural cesium, iodine, of ores, power plants, sources radon weapons Water Pollution Category Examples Sources B. Causes Ecosystem Disruption Sediment Soil, silt Land erosion Plant nutrients Nitrates, phosphates, Agricultural and urban ammonium fertilizers, sewage, manure OxygenAnimal waste and Sewage, agricultural demanding wastes plant residues runoff, paper mills, food processing Thermal Heat Power plants, industrial cooling 5 Infectious agents • Pathogens (disease-causing organisms) • Waterborne diseases: typhoid, cholera, bacterial dysentery, polio, infectious hepatitis, E. Coli, and schistosomiasis • Main culprit: untreated or improperly treated human waste – Contamination of water supply – Animal feedlot waste runoff into drinking water supply or food processing factories Classic case: Cholera • Cholera: intestinal disease, that if severe enough, leads to death (possibly within hours of exposure) – Treatable today • 1854 London: sewage dumped into River Thames – Cholera believed to be from “bad air” – John Snow proved it was from water 6 Organic chemicals • Chemicals released in the environment (includes those intentionally and unintentionally produced) • Natural and synthetic organic chemicals – Pesticides, plastics, pharmaceuticals Organic chemicals • Carried by wind and water • Persistent organic pollutants (POPs): stick around and travel in food chain – “Dirty Dozen”: aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, toxaphene, PCBs, dioxins and furans • 1,000 wells shutdown in Florida with toxic levels of pesticides Plant nutrients & oxygen-demanding wastes • Organic waste (sewage, food waste) produce oxygen-demanding bacteria • Fertilizer, plant operations, automobile waste 7 Inorganic pollutants • Include natural breakdown and release of minerals into the water • Inorganic pollutants: metals, minerals, acids, salts, nitrates – Some are not toxic in small amounts • Metals and industrial solvents: – Hexavalent chromium (a carcinogen) found in ground water in Hinkley, CA. • Groundwater exceeded the Maximum Contaminant Level of 0.10 ppm with 0.58 ppm Metals • Mercury, lead, cadmium, tin, and nickel – highly toxic in very small doses – Most widespread is mercury – released from coal-burning power plants and deposited in lakes – Predator fish eat small fish – lead to higher doses of mercury – Affects: brain, heart, kidneys, lungs, and immune system Arsenic • Odorless and tasteless semi-metal • Occurs naturally and from agricultural and industrial practices. • Possible effects: digestive, skin, partial paralysis, and cancer. • New drinking water standard: 0.010 parts per million (10 parts per billion) – EPA set water system deadline for January 23, 2006. – Usually found in ground wells vs. surface water • Problem in developing countries 8 USGS report (2002) • Sampled 130 streams, testing for 95 contaminants – Drinking water standards only exist for 14 of the 95 contaminants Detection frequency (% of samples) Detection frequency 100 90 80 70 60 50 40 30 20 10 0 Steroids Nonprescription drugs Thermal pollution Insect repellent Dis infectants Antibiotics Insecticides Horm ones Other pres cription drugs • Raising or lowering of water temperatures affects aquatic life • Typically raised by discharging heated water from industrial facilities – Electric power plants, petroleum refineries, paper mills, food-processing factories all release “cooling water” – Thermal plume: heated water discharged into river and lake Thermal pollution • Regulated by EPA • Can construct artificial cooling ponds or cooling towers • Some thermal pollution beneficial: – Attract wildlife – Manatees of Florida – Can be hazardous – if plant shuts down, even temporarily, fatal to wildlife 9