prakt3 (3) английский

UNIT 7 WASTE DISPOSAL
Assignment 1
Take a look at the following pictures displaying different waste disposal methods and match them with the names.
1) Incineration 3) Hazardous waste containers 5) Recycling
2) Sanitary Landfill 4) Ocean dumping 6) Open dumping/landfill






A __________________ B __________________




C __________________ D __________________





E __________________ F __________________

Assignment 2
You are going to read the text about hazardous waste and its disposal. Think of the most suitable heading for each paragraph (1-3).
Headings: Waste minimization and recycling

Disposal options
Hazardous waste

1

The Resource Conservation and Recovery Act (RCRA), enacted in 1976, defines hazardous waste as a liquid, solid, sludge, or containerized gas waste substance that due to its quantity, concentration, or chemical properties may cause significant threats to human health or the environment if managed improperly. U.S. legislation considers a waste hazardous if it is corrosive, flammable, unstable, or toxic. Sources of hazardous waste may include industry, research, medical, household, chemical producers, agriculture, and mining, as well as many others.
Most hazardous waste comes from industrial sources. The EPA specifies four different categories of hazardous waste that are subject to regulation: hazardous wastes from nonspecific sources involved in industrial processes such as spent halogenated solvents; hazardous wastes from specific industrial sources, such as untreated wastewater from the production of the herbicide 2,4-dichlorophenoxyacetic acid (2,4,-d); commercial chemical products that may be discarded (such as benzene) used in the manufacture of drugs, detergents, lubricants, dyes and pesticides; and wastes that are classified as toxic, such as vinyl chloride. Hazardous waste from many industrial processes include solvents such as methylene chloride, a probable carcinogen that is commonly used in paint removers. Trichloroethylene, a solvent that has been found in groundwater is monitored and regulated in drinking water in the United States. Drinking or breathing high levels of trichloroethylene can lead to damage of the liver, lung, and nervous system. In many industries the sludge remaining after treatment of wastewater accounts for much of the generated hazardous waste. Sludges and wastewater from electroplating operations commonly contain cadmium, copper, lead, and nickel. These heavy metals are found in the sediment of Lake Huron and have been associated with degradation of benthos and planktonic communities. Heavy metals can impact the health of humans and wildlife in a variety of ways: lead interferes with the nervous system and can lead to learning disabilities in children and cadmium accumulates in humans and animals and can lead to kidney disfunction. Household products that contain hazardous ingredients are not regulated under RCRA but should be disposed of separately from municipal garbage following label instructions. Household hazardous waste (HHW) can include used motor oil, paint thinners and removers, wood preservers, batteries, fluorescent lights that contain mercury, and unused pesticides.
The U.S. Environmental Protection Agency (EPA) and state regulatory agencies collect information about the generation, management, and final disposal of hazardous wastes regulated under RCRA. This report gives detailed data on hazardous waste generation and waste management practices for treatment, storage, and disposal facilities.

2

Recycling and waste minimization may be the best ways to deal with hazardous waste. Waste minimization reduces the volume of waste generated, whereas recycling means that less hazardous waste requires disposal. Techniques for waste minimization may include audits, better inventory management, production process/equipment modifications, and operational/maintenance procedures. Raw material changes, volume reductions, nonhazardous material substitutions, reuse, or recovery also reduce hazardous waste production. For example biodegradable, nontoxic lactate esters are solvents manufactured from renewable carbohydrate sources that can be substituted for toxic halogenated solvents.
The EPA's Industrial Toxics Project is a nonregulatory program initiated in 1990 to achieve, voluntarily, overall reductions for seventeen toxic chemicals reported in the government's Toxics Release Inventory (TRI), including cadmium, lead, mercury, trichloroethylene, and toluene. The recycling of waste through waste exchanges is one aspect of industrial ecology and another way to address the issue of hazardous waste disposal. For example the sludge that accumulates in scrubbers removing sulfur dioxide from power plant smokestacks contains calcium sulfate, which can be recycled in wallboard. Waste exchange also promotes the use of one company's waste as another company's raw material. Waste exchanges typically list both available and desired materials. Several regional waste exchanges exist, as well as exchanges within small geographic regions. Some exchanges charge for their services, whereas others are supported by grants.

3

Workers wearing hazardous materials suits, neutralizing hazardous materials.

Disposal options for hazardous waste include landfills, injection wells, incineration, and bioremediation, as well as several others. The greatest concern with the disposal of hazardous waste in landfills or injection wells is that toxic substances will leak into surrounding groundwater. Groundwater is a major source of drinking water worldwide and once it is contaminated, pollutants are extremely difficult and costly to remove. In some instances, it is impossible to remove groundwater contamination. The ideal disposal method is the destruction and conversion of hazardous waste to a non-hazardous form. New technology for hazardous and mixed low-level radioactive waste conversion includes a high-temperature plasma torch that converts low-level radioactive wastes to environmentally safe glass. Conversion to environmentally safe substances can be very expensive for some types of hazardous wastes and technically impossible for others, creating the need for alternative disposal methods.
The most common form of hazardous waste disposal in the United States is landfilling. Hazardous waste landfills are highly regulated and are required to include clay liners, monitoring wells, and groundwater barriers. The 1984 Hazardous Solid Waste Amendments require the monitoring of groundwater near landfills for thirty years. Injection wells may be used to inject hazardous waste deep into the earth, but problems result with aquifer contamination and the ultimate fate of the hazardous waste after injection is unknown.
Incineration may be an effective way to convert hazardous waste into a nonhazardous form while greatly decreasing its volume. The waste is burned and converted into carbon dioxide, water, and inorganic by-products. The problems associated with incineration are high capital and operating costs, and the disposal of ash, which may contain hazardous substances. In addition, incinerating wastes can cause mercury and dioxin air pollution. Bioremediation may also be used in situ or ex situ to convert hazardous wastes to nontoxic by-products using microorganisms and natural degradation processes. Biodegradation requires very long treatment times and it may be difficult to control or enhance natural degradation processes. Phytoremediation, the process by which plants absorb and in some cases degrade hazardous substances in the environment, is being investigated as an emerging cleanup technology. For example poplar trees have been shown to break down the herbicide atrazine, mustard plants will remove lead from soil, and the alpine pennycress plant will take large amounts of heavy metals and also uranium from soil.
When hazardous waste is to be transported off-site for disposal, the waste generator prepares a shipping document called a manifest. This form must accompany the waste to its final destination and is used to track the waste's movements from "cradle to grave."
(http://www.pollutionissues.com/Fo-Hi/Hazardous-Waste.html)

Assignment 3
Complete the table below in accordance with the text.
Method of waste disposal Principle of working Examples
(if mentioned) Problems associated with the method
Landfill
Injection well
Incineration
Bioremediation
Transportation off-site


Assignment 4
For questions 1-15, read the text below and think of the word from the box which best fits each space. Use only one word in each space.
which/that, before, not, rid, few, on, into/to, with, and, a, of/for, so, than, all/any, other

DEALING WITH WASTE PLASTIC
Every year people throw away millions of tonnes of plastic bottles, boxes and wrapping. These create huge mountains of waste (1) __________ are extremely hard to get (2) __________ of. Now, a new recycling process promises to reduce this problem by turning old plastic (3) __________ new. Scientists have taken (4) __________ long time to develop their ideas because waste plastic has always been a bigger problem (5) ___________ substances like waste paper. You can bury plastic, but it is years (6) __________ it breaks down. If you burn it, it just becomes another form of pollution. A (7) __________ products, for example bottles, can be re-used but it is expensive or difficult to do this (8) __________ a lot of plastic products. Now a group of companies has developed a new method (9) __________ recycling that could save almost (10) _________ plastic waste. The advantage of the new process is that nearly every type of waste plastic can be used: it does (11) __________ have to be sorted. In addition, labels and ink may be left (12) __________ the products. Everything is simply mixed together (13) __________ heated to more than 400 degrees centigrade (14) __________ that it melts. It is then cooled, producing a waxy substance that can be used to make new plastic products such as bags, bottles and, among (15) ___________ things, computer hardware.

Assignment 5
Use the words given in capitals to fulfill the spaces.
Recycling steel cans
Cans made of steel are very easy to remove from domestic rubbish because steel is the only common metal that is 1__________ to magnets. Many waste removal authorities have taken advantage of this fact and have 2__________ large magnets, which, to put it simply, pull all steel containers out of the general 3__________ rubbish. The system is known as 'magnetic 4__________' and it has two great advantages.
Firstly, 5___________ most recycling schemes, the recycling of steel cans through 'magnetic extraction' requires almost no effort from the public. As long as you throw your used steel can into the rubbish bin, it will be collected and then the waste removal authority will do the rest. Other 6__________ cannot be recycled 7___________ the public collect the material and take it, usually by car, to a central collection point. This often uses up more energy in petrol than is eventually saved by recycling the material.
8___________, local authorities actually save public money through recovering used steel cans. Magnetic extraction equipment is simple and cheap, and the steel that has been saved is 9___________ to companies who re-use it for making new steel products. As the value of the metal is 10__________ than the cost of magnetic extraction, the process has financial benefits.
So, magnetic recycling of steel cans from waste saves you time, effort and money, as well as saving energy for us all. ATTRACTED

SOLD
PACKAGING
UNLESS

INSTALLED


GREATER

UNLIKE
SECONDLY
HOUSEHOLD


EXTRACTION

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