Hazardous Wastes. Read this selection to learn about the problems posed by hazardous wastes. Then answer the questions that follow.

Transcription

1 North arolina Testing Program Read this selection to learn about the problems posed by hazardous wastes. Then answer the questions that follow. Hazardous Wastes Types of Hazardous Wastes Many people picture hazardous wastes as bubbling chemicals, thick fumes, or oozing slime. ut even some harmless-looking, common materials such as window cleaner, radio batteries, and nail polish remover can become hazardous wastes. Hazardous waste is any material that can be harmful to human health or the environment if it is not properly disposed of. Hazardous wastes are created during the manufacture of many household products. Many more are produced as a result of agriculture, industry, military operations, and research at hospitals and scientific laboratories. Hazardous wastes are classified into four categories: toxic, explosive, flammable, and corrosive. Figure 13 gives some examples of these types of waste. Toxic wastes, or poisonous wastes, are wastes that can damage the health of humans and other organisms. Explosive wastes are wastes that react very quickly when exposed to air or water, or that explode when they are dropped. Explosive wastes are also called reactive wastes. Flammable wastes catch fire easily and can begin burning at fairly low temperatures. orrosive wastes are wastes that dissolve or eat through many materials. Other wastes that require special disposal are radioactive wastes. Radioactive wastes are wastes that contain unstable atoms. These unstable atoms give off radiation that can cause cancer and other diseases. There are two types of radioactive wastes: high-level waste and low-level waste. n example of high-level radioactive waste is the used fuel from nuclear reactors. Lowlevel radioactive wastes are produced when radioactive minerals such as uranium are mined. They are also produced at some medical and scientific research sites. Radioactive waste can remain dangerous for thousands of years. ategory: Radioactive Examples: Uranium, plutonium RIOTIVE 7 ategory: Toxic Examples: hlorine, P s, mercury POISON 6 ORROSIVE 8 ategory: orrosive Examples: Hydrochloric acid, sodium hydroxide ategory: Flammable Example: Kerosene FLMMLE 3 ategory: Explosive Example: Nitroglycerin EXPLOSIVES Figure 13 Vehicles transporting dangerous materials must use signs like these to alert people of the potential dangers of their loads. Page 1 Published pril May reproduce for instructional and

2 North arolina Testing Program Health Effects of Hazardous Wastes person can be exposed to hazardous wastes by breathing, eating or drinking, or touching them. Many factors determine the effects of a hazardous substance on a person. One factor is how harmful the substance is. nother factor is how much of the substance a person is exposed to. third factor is how long the exposure lasts. person may be exposed for a short time, such as a child accidentally drinking antifreeze. Or a person may be exposed for many years, as were the residents of Love anal. Finally, a person s age, weight, and health all influence how a substance affects that person. In general, short-term exposure to hazardous wastes may cause irritation or more severe health problems. These health problems can include breathing difficulties, internal bleeding, paralysis, coma, and even death. Long-term exposure to hazardous wastes may cause diseases, such as cancer, and may damage body organs, including the brain, liver, kidneys, and lungs. These effects may eventually be life threatening. isposal of Hazardous Wastes It is hard to safely dispose of hazardous wastes. urying them can pollute the soil or groundwater. Releasing wastes into lakes or rivers can pollute surface water. urning hazardous wastes can pollute the air. You can see the problem! Methods of hazardous waste disposal include burial in landfills, incineration, and breakdown by living organisms. nother method involves storing liquid wastes in Figure 15 Superfund sites are located all over the country. This map shows the number of sites in different states in a recent year. deep rock layers. Hazardous wastes are most often disposed of in carefully designed landfills. These landfills are lined with clay and plastic to keep chemicals from leaking into the soil and groundwater. clay and plastic cover prevents rainwater from seeping into the wastes. Scientists have developed some other methods for disposing of hazardous waste. For example, wastes can be incinerated at very high temperatures. Incineration often Page 2 Published pril May reproduce for instructional and

3 North arolina Testing Program breaks down harmful compounds into less harmful ones. acteria, algae, and fungi can break down some hazardous chemicals. nother disposal method involves pumping liquid wastes into a layer of sandstone or limestone thousands of meters underground. The wastes spread throughout this soft rock layer. ut wastes cannot move through the thicker, harder layers of rock above and below. few types of hazardous waste, such as motor oil and lead-acid car batteries, can even be recycled. Scientists have not been able to develop completely safe methods for disposing of radioactive waste. Some techniques used today are mixing the waste with concrete or sealing it in abandoned mine shafts. High-level radioactive wastes are currently stored in vaults dug hundreds of meters underground or in concrete and steel containers above ground. ut these storage areas are temporary. Scientists are still searching for methods that will provide safe, permanent disposal of radioactive wastes. In 1980, ongress passed a law creating a hazardous waste site cleanup program called the Superfund. The law determines who should pay for the cleanup. This can include any businesses or people that have ever owned or operated the property, or have ever contributed wastes to it. Hazardous Wastes from Prentice Hall Science Explorer: Environmental Science 2002 by Pearson Education Inc., publishing as Prentice Hall. Used by permission. 1. To which category of hazardous waste does kerosene belong? corrosive explosive flammable toxic 2. Which conclusion about the health effects of hazardous waste is based on the information in the selection? person s general health is a factor in how he or she is affected by hazardous waste. The damaging effects of exposure to hazardous waste usually show up immediately. Most hazardous substances tend to affect people in the same way. Scientists do not understand many of the effects of hazardous waste. Page 3 Published pril May reproduce for instructional and

4 North arolina Testing Program 3. How is short-term exposure to hazardous wastes similar to long-term exposure to hazardous wastes? 4. ccording to the selection, what is the main problem in disposing of hazardous waste? oth cause identical health problems. oth can cause serious health problems. Neither can be avoided by a job change. Neither is caused by human carelessness. inventing uses for recycled waste finding a method that is affordable protecting the workers who are handling it preventing the waste from polluting the environment Page 4 Published pril May reproduce for instructional and

5 North arolina Testing Program 5. The diagram below organizes some of the information in the selection. burial in special landfills incinerate at high temperatures WYS TO ISPOSE OF HZROUS WSTE store liquid wastes in deep rock Which of the following belongs in the empty circle? release into rivers release into the air breakdown by bacteria or fungi pump into surface ground layers Page 5 Published pril May reproduce for instructional and

6 North arolina Testing Program 6. ased on the selection, how does the disposal of motor oil differ from the disposal of substances such as window cleaners or nail polish? It can be recycled. It can be buried. It can be incinerated. It can be pumped underground. End of Set In compliance with federal law, including the provisions of Title IX of the Education mendments of 1972, the epartment of Public Instruction does not discriminate on the basis of race, sex, religion, color, national or ethnic origin, age, disability, or military service in its policies, programs, activities, admissions or employment. Page 6 Published pril May reproduce for instructional and

7 nswers to Grade 7 Reading omprehension Sample Items Question orrect Objective Passage Title Number nswer ategory Thinking Skill Number Hazardous Wastes 1 ognition Knowledge 2.01 Hazardous Wastes 2 Interpretation Integrating 2.01 Hazardous Wastes 3 ritical Stance Organizing 2.01 Hazardous Wastes 4 ognition Knowledge 2.01 Hazardous Wastes 5 ognition Organizing 2.01 Hazardous Wastes 6 ritical Stance Organizing 2.01 Wednesday, pril 07, 2004 Page 1 of 1