Реферат: Landfills Essay Research Paper Landfillsby Brandon NollLandfills
Название: Landfills Essay Research Paper Landfillsby Brandon NollLandfills Раздел: Топики по английскому языку Тип: реферат |
Landfills Essay, Research Paper Landfills by Brandon Noll Landfills are places where all our trash goes when we no longer need it. Each person in the United States makes an average 4.5 pounds of garbage per year. And every year the United States as a whole produces 4,036,300,000 metric tons of solid waste each year. All of this waste does not just disappear, 80 percent ends up in landfills. In the following report I am going to tell you about the different types of landfills there are, the problems that have come up with the building of landfills, and what can be done and is being done to reduce the amount of waste going into landfills. First of all, “What are the different types of landfills?” Well, there are two different types of landfills; the first type is the old type of landfill which are often called open dumps where trash and other waste were thrown, often times in a ditch or just placed in a pile. These open dumps are a poor method of waste disposal because they cause numerous environmental problems. For example, they can ruin an area’s appearance and provide a home and breeding ground for animals that spread disease. In addition, rain water drains through refuse and can carry harmful substances to nearby streams and to water that is used for drinking. Unregulated dumps where waste is burned in the open can cause smoke and foul-smelling air. Burning in open dumps has been prohibited in the United States. The other type of landfill is most often called a sanitary landfill. Properly operated sanitary landfills cause little damage to the environment. The waste is firmly packed by heavy tractors and other machinery, and covered with earth each day. The cover of earth prevents insects and other animals from getting into the refuse. In time, sanitary landfill sites become filled up. Many communities then cover the site with earth a final time and use the area for recreational purposes. Concern for the environment has led to the establishment of many strict laws and ordinances to control land disposal sites. A secure sanitary landfill is lined with materials like plastic or clay that prevents water from carrying leachates, or dissolved substances from the refuse into underground water supplies. Pipes collect the water for transfer to a treatment plant that removes the leachates in the groundwater. Pipes sunk into the landfill allow gases to escape or be collected for fuel. Another variation of the landfill concept greatly increases the disposal capacity of certain cites and provides recreational slopes in otherwise flat terrain. In this variation, wastes are compacted in layers to create a landscaped hill 100 feet (30 meters) or more in height. Such hills, sometimes nicknamed Mount Trashmore, have been built in Dupage County and Evanston, Illinois; Virginia Beach, Virginia; Frankfurt, Germany; and Stockholm, Sweden. Not all potential landfill sites are suitable for conversion into hills, but many are. In regions where natural hills are scarce, a carefully built, covered, and landscaped hill of waste can solve a waste-disposal problem and at the same time actually enhance the environment. Another site sometimes used for waste disposal, and under consideration for more extensive use is the ocean floor. A major deterrent to wider use of the ocean floor is the long term threat of contamination of the deep-sea environment by materials that injure marine life. What are the problems in landfills today? Operators of landfills expect the refuse in them to decay. However, environmental experts have found that many materials are called biodegradable, because they decompose when tightly packed in a landfill. The decomposition of cellulose in a landfill is accompanied by a very slow formation of methane gas, which seeps out into the atmosphere. When methane gas forms by natural decay swamps it is called swamp, and or marsh gas. Normally, much more methane is released into the air by natural decay of trees and other vegetation than by the decay of waste in landfills. In a rare misapplication of landfilling too close to a building, the methane gas may seep into and accumulate inside the building and cause an explosion. A problem of landfilling in metropolitan areas is that as the need for waste disposal grows, the number of suitable sites diminishes. This problem is enormously complicated when the city has completely surrounded by residential suburbs that are hostile to all forms of waste processing in their areas, especially the processing of waste from a neighboring community. The well-founded hostility to the formerly widespread practice of open dumping has, however, prejudiced many taxpayers against any form of landfilling regardless of the demonstrated success of the sanitary landfill method. Incineration is one process that reduces the amount of waste that is contained in landfills. Incineration is the process of burning waste products. Many large cities use incinerators because they do not have suitable land waste disposal sites. Older municipal incinerators often lack adequate air pollution control devices. Burning in many of these incineration plants releases gases and solid particles that may harm human health, damage property, and kill plants. In the United States and Canada, incinerators are required to limit the amount of pollution they release. Ash produced by incineration should be monitored to ensure that it will not harm the environment. Composting is also a method of reducing the amount of waste going to landfills. Composting is the production of useful soil conditioning material from the cellulosic and organic portions of community wastes remains an attractive concept, but most large-scale attempts have failed because of marketing problems and costs. Research in composition is continuing, and under special supply and marketing conditions, composting will eventually find some limited applications. In the large industrial city of Sao Paulo, Brazil, a Danish compost system has been successful because nearby small vegetable farms, operated largely by Japanese immigrants, have found the compost useful for improving the compacted soil of the area. Another method of waste reduction is recycling. Some people think that most of the material in landfills was fast food packaging, but it has been found that this packaging only takes up one percent of the trash. Diapers take up less than one percent, and plastic takes up nine to twelve percent of the material in landfills. The most commonly found item in a landfill is newspapers. They make up about fourteen percent of the trash that is found in landfills. What people need to start doing is recycling material that can be reused in a different ways that we can save some of the room in the landfills. Many things can be recycled like paper, plastic, aluminum, steel, tires, oil, and glass, these things can be reused which can save many important things in our world. When we recycle we save trees, energy, and air pollution. Recycling and waste reduction helps lessen the amount of refuse that is buried in landfills or burned in incinerators. Recycling is the process of reusing materials instead of throwing them away. Commonly recycled materials include metals, glass, and paper. Waste reduction is the process by of producing less waste. For example, people can reduce waste by using handkerchiefs instead of disposable tissues. Municipal solid waste garbage is not as lethal as toxic and hazardous waste, but its disposal is reaching the point of crisis in many cities. Much of the 20,000 tons New York City produces each day is taken to Fresh Kills Landfill. This gigantic waste mound on Long Island, covering 3,000 acres, leaches two million gallons of toxic fluid in the ground and surface water daily. Facing mounting costs and environmental problem, New York City has decided to phase into mandatory recycling. Few people want to live or work near a garbage disposal site. As it grows increasingly difficult to find locations for new landfills and incinerators, recycling and waste reduction will gain importance methods of waste management. For example, in the late 1980’s, Americans buried about seventy three percent of their municipal solid waste in landfills, recycled thirteen percent of it, and burned fourteen percent of it in incinerators. Difficulties with the containment of toxins have led to a promising discovery. When hazardous household wastes come into contact with rain water, a toxic liquid known as leachate is created. Engineers have struggled to find ways of minimizing leachate but are now learning that it may have an important use. By recirculating leachate through landfills, the rate of decomposition is greatly increased. This development could lead to a new vision of landfilling…the permanent dumping ground of the past may eventually become an efficient eater of trash. From open dumps, to sanitary landfills, landfills have come a long way. But, there is still a lot of problems with them and things to be learned I hope have informed you of many of in this report. |