Chapter 19 Land Pollution

1. Chapter 19Land Pollution

2. Definition • 1976- Congress defined solid wastes as ALL garbage, refuse and sludge products from Agriculture, Forestry, Mining and Municipalities. • History- 500 BC Athens had laws that created first garbage dump. Europe, however, had garbage in the streets as late as 1800’s.

3. History continued • 1892-typhoid/cholera forced NY to establish daily pick up of garbage from city streets, loaded on barges and dumped in the ocean…. Good idea?....for how long? • First landfills (sites where wastes are buried) were established to alleviate above problem. • 70% of today’s garbage is found in landfills

4. % by volume of types of wastes created by communities Paper 50% Glass 1% Metal 6% Misc. 20% Plastic 10% Organic 13%

5. The Landfill Problem • 1. open landfills-easier/convenient; unfortunately it was a cause of vermin infestations, odors and possibly diseases. • rainfall carried pollutio into groundwater, this has made this type of dumping illegal in many states.

6. Sanitary Landfills • This type of landfills has wastes spread out in layers of 3m in thickness and compacted by bulldozers; Soil (15cm) is then spread on top of it and compacted. This goes on until a desired height of garbage is reached. Final layer of soil about 60cm thick is spread on area, grass and trees are planted. • Methane ventilation pipes are constructed and sometimes the gas is collected and sold. • Leaching of toxins is avoided by lining the area with plastic and clay. (Not always successful!)

7. Secure Chemical Landfill

8. Hazardous Wastes • Definition: solids, liquids or gaseous wastes that are potentially harmful to humans and the environment, even in low concentrations. • Read article on the “Love Canal Incident!”

9. Classification of Hazardous Wastes • Through classification the EPA can figure out the proper way to dispose of them. • Reactive wastes- explosive wastes, such as the element Sodium (Na) • Corrosive wastes- wastes that can eat through steel and other materials. (battery acid, lye (Drano)) • Ignitable wastes- can burst into flames at low temperatures. (paint thinners, cleaning fluids and oils.)

10. Categories continues • Toxic wastes- poisonous to people. Cause health problems such as cancer and/or birth defects. (cyanide, mercury, lead, arsenic and some pesticides.) • Radioactive wastes- wastes that give off radiations. (mining of uranium, plutonium etc., materials used in nuclear power plants, mining and processing radioactive ores.) • Medical wastes- tissue samples, blood vials, syringes, etc. • Home wastes- bleaches, ammonia, lye,etc.

11. Topsoil erosion • Soil cycle: mechanical and chemical weathering forms soil, natural forces such as wind and running water carry it away in a process called EROSION • SOIL LOSS- major reasons: 1. overgrazing, deforestation, poor irrigation and cultivation practices cause soil loss and desertification. desertification occurs most often in dry regions that border on deserts. 30% of Earth’s land has undergone desertification!

12. Soil Loss Cont. • Recent report from the U.S. department of agriculture estimates that soil loss from erosion will threaten 1/3 of all farmland in the U.S. • Soil erosion is not limited to US; countries uch as China lose top soil at a rate of 43 metric tons/hectare/year, compared to US that is 18 metric tons/ hectare/year. Guatemala (mountain regions) 200/3600 metric tons/hectare/year. • The major cause is wind and WATER!

13. Soil Conservation and Land Management • New methods used by Farmer to help with the problem • Strip-cropping- Farmland plowed so that plowed strips are separated by planted strips. Planted strips reduces soil erosion • Contour farming- plowing occurs along a slope instead of across it. The furrows between rows of crops collect water, preventing heavy soil erosion

14. Continue • Terracing- series of platforms called terraces are built into the slope of a hill. A vertical step separate each terrace from the next. This slows water flow, water soaks into soil.

15. Cont. • Shelter Belt- rows of trees may be planted along the outer edges of a field. These rows of trees are called windbreakers, they slow down erosion by slowing down the wind.

16. Controlling pollution on Land • The best way to control pollution on Land is to avoid making it. Disposable items make up ¼ of all waste placed in landfills. • By substituting reusable or recyclable goods can reduce volume of waste. • What are some changes you can make?

17. Changes • Cloth napkins or handkerchiefs, china instead of paper plates, cloth diapers instead of paper • Recycling-paper metal glass, are being sorted from garbage and recycled/ • Some materials are naturally recycled, these we call BIODEGRADABLE. This means that some substances decompose easily and enrich the soil. Composting is a man made way to form humus

18. Disposing of hazardous wastes • Waste exchange- use of hazardous wastes by other companies that need that material for the making of their product. Win-win situation • Deep-well injection- petroleum Co. take their liquid wastes and pump it into deep porous rocks through lined pipes. Rocks located well below drinking water aquifers

19. Disposal Cont. • Secure Chemical Landfill- land filled built in area of NONPOROUS bedrock. This prevents leaching of pollutants into ground water. In addition the top of landfill is covered with layer of clay to keep water out.

20. Disposal Cont. • Controlled Incinerator- burning of wastes at high temp. 542C-1662Celsius. Here complete burning takes place. Best method for getting rid of Hazardous wastes. However, very expensive.

21. Cont. • Chemical and Biological Treatment Plants- neutralizes hazardous materials and makes them harmless. Once contained easier to dispose. • Radioactive Waste Disposal- at present radioactive wastes are placed in water. Water together with the waste is sealed in stainless steel tanks which are encased in concrete. These are placed in concrete vaults underground.

22. Legislation • EPA established in the 1970 to carry out federal laws designed to protect the environment. Page 317 has table of major laws passed because of the EPA. • To protect communities from the dangers of hazardous wastes, Congress passed a law nicknamed SUPERFUND. Official name is CERCLA. Its job is clean up hazardous wastes, making polluters pay, encouraging research for the reduction, treatment, and disposal of hazardous wastes.

23. Legislation cont. • Not enough money is being allocated to the EPA to truly make a dent in this problem. Americans and other cities ship their hazardous waste to developing nations. This is a “delicate issue!” • Many governments and industries are working to reduce hazardous waste. Pollution prevention, grants for further research, are a few of the methods used to cut down on generating wastes