Реферат на тему Landfills Essay Research Paper Landfills A Growing
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Landfills Essay, Research Paper
Landfills- A Growing Menace When asked to think of the largest man made structure, people will invariably come up with an answer like The Great Wall of China, the Great Pyramids, or the Taj Majal. In contrast to these striking achievements of mankind is the Durham Road Landfill outside San Francisco, which occupies over seventy million cubic feet. It is a sad monument to the excesses of modern society [Gore 151]. One must think this huge reservoir of garbage must be the largest thing ever produced by human hands then. Unhappily, this is not the case. The Fresh Kills Landfill, located on Staten Island, is the largest landfill in the world. It sports an elevation of 155 feet, an estimated mass of 100 million tons, and a volume of 2.9 billion cubic feet. In total acreage, it is equal to 16,000 baseball diamonds [Miller 526]. By the year 2005, when the landfill is projected to close, its elevation will reach 505 feet above sea level, making it the highest point along the Eastern Seaboard, from Florida to Maine. At that height, the mound will constitute a hazard to air traffic at Newark airport [Rathje 3-4]. The area now encompassed by the Fresh Kills (Kills is from the Dutch word for creek) Landfill was originally a tidal marsh. In 1948, New York City planner Robert Moses developed a highly praised project to deposit municipal garbage in the swamp until the level of the land was above sea level. A study of the area predicted the marsh would be filled by the year 1968. He then planned to develop the area, building houses and attracting light industry over the landfill. The Fresh Kills Landfill was originally meant to be a conservation project that would benefit the environment. The mayor of New York City issued a report titled “The Fresh Kills Landfill Project” in 1951 which stated, in part, that the project “cannot fail to affect constructively a wide area around it.” The report ended by stating, “It is at once practical and idealistic” [Rathje 4]. One must appreciate the irony in the fact that Robert Moses was considered a leading conservationist in his time. His major accomplishments include building asphalt parking lots throughout the New York Metro area, paved roads in and out of city parks, and the development of Jones Beach, now the most polluted and overcrowded piece of shoreline in the Northeast United States. In Stewart Udall’s book The Quiet Crisis, the former Secretary of the Interior praises Moses. The JFK cabinet member calls the Jones Beach development “an imaginative solution … (the) supreme answer to the ever-present problems of overcrowding” [Udall 163-4]. JFK’s introduction to the book provides this foreboding passage: “Each generation must deal anew with the raiders, with the scramble to use public resources for private profit, and with the tendency to prefer short-run profits to long-run necessities. The crisis may be quiet, but it is urgent” [Udall xii]. It is these long term effects that the developers of landfills often fail to consider. Oddly, the subject of landfills is never broached in Udall’s book; in 1963 landfills were a non-issue. A modern state-of-the-art sanitary landfill is a graveyard for garbage, where deposited wastes are compacted, spread in thin layers, and covered daily with clay or synthetic foam. The modern landfill is lined with multiple, impermeable layers of clay, sand, and plastic before any garbage is deposited. This liner prevents liquids, called leachates, from percolating into the groundwater. Leachates result from rain water mixing with fluids in the garbage, making a highly toxic fluid containing inks, heavy metals, and other poisonous compounds. Ideally, leachates are pumped up from collection points along the bottom of the landfill and either shipped to liquid waste disposal points or re-introduced into the upper layers of garbage to resume the cycle. Unfortunately, most landfills have no such pumping system. [Miller 527]. Until the formation of the Environmental Protection Agency by President Nixon in 1970, there were virtually no regulations governing the construction, operation, and closure of landfills. As a result of this lack of legislation, 85 percent of all landfills existing in this country are unlined. Many of these landfills are located in close proximity to aquifers or other groundwater features, or near geologically unstable sites. Many older landfills are leaking toxins into our water supply at this very moment, with no way to stop them. For example, the Fresh Kills landfill leaks an estimated one million gallons of toxic sludge into the surrounding water table every day [Miller 527]. Sanitary landfills do offer certain advantages however. Offensive odors, which characterized waste depositories at one time are dramatically reduced by the daily cover of clay or other material over the garbage. Vermin and insects are also denied a free meal and the opportunity to spread disease by the daily layer of deposited clay. Furthermore, modern landfills are less of an eyesore than their older counterparts. However, the sources of these positive affects are the very reasons for some of the significant drawbacks to landfills [Turk and Turk 486]. The daily compacting and covering of the garbage deposits squeezes the available oxygen out of the trash. Whatever aerobic bacteria are present in the garbage are soon suffocated and decomposition stops. Anaerobic bacteria, by their very nature, are not present in appreciable numbers in our biosphere. What few manage to enter and survive in the garbage deposits are slow-acting and perform little in the way of breaking down the materials. In other words, rather than the giant degrading compost heap most people imagine, a landfill is actually a huge mummification center. Hot dogs and bananas, decades old, have been recovered from landfills, still recognizable in their mummified state [Rathje 111-12]. What little decomposition does occur in landfills generates vast amounts of methane gas, one of the significant greenhouse effect gasses. Some landfills have built-in processes to reclaim the methane from the atmosphere. The Fresh Kills landfill pipes methane gas directly into 12,000 homes, but in most instances the gas is either burned off or leaked directly into the atmosphere. Based on ice core samples from Antarctica, the methane concentration in the Earth’s atmosphere, over the past 160,000 years, has fluctuated between 0.3 and 0.7 parts per million. The methane levels in the atmosphere are now triple that.[McKibben 17-17]. It is not only the modern landfills that defy decomposition. Because of the stench from the thousand year old refuse of an ancient Roman landfill, an 1884 archaeological dig had to be halted periodically so the workers could get fresh air.[Rathje 113] In today’s landfills decomposition is negligible. While the total tonnage of garbage decreases over years, due mostly to decay, the volume varies less than ten percent. Most of the actual short-term rotting is from scraps of prepared food. Plastics present in landfills will most likely be there forever. Even the most unstable plastic requires intense sunlight to decompose, and sunlight is denied in a sanitary landfill. Newspapers from before World War Two are still readable in these landfills; they have in fact become important date markers for scientists examining garbage strata in landfills [Rathje 112-13]. If burning garbage and dumping garbage at sea are unacceptable, what are the alternatives? Of the landfills, sanitary and otherwise, open for business in 1979, 85 percent are now closed [Miller 527]. Where is all the garbage going? Some municipalities are shipping garbage to other cities, or even other states, a costly proposition. Larger metropolitan agencies have even taken to shipping garbage to Third World countries who are strapped for cash and eager for the money that comes along with the trash. This, of course, only transfers the problem from one population to the other. Stories of wandering garbage barges and orphaned garbage trains have appeared in American newspapers. Covert garbage disposal has become a lucrative business, as the plethora of medical waste washed up along the New Jersey shoreline proves. Despite these horror stories, recycling really is making a difference. Newspapers, which used to make up 25 to 40 percent of the garbage volume of a typical city, are now effectively eliminated from household garbage. Aluminum can recycling has become a profitable enterprise, both for the economically disadvantaged and for the average homeowner trying to offset the ever-increasing cost of garbage collection. Construction waste is now barred from landfills in most areas; this high volume material is now recycled or put to Earth-friendly uses, such as making barrier reefs. Plans for the safe incineration of refuse to generate electric power have presented some highly contentious issues. The ash from such incinerators is normally highly toxic, since it concentrates existing toxins. Citizens object to these plants, as long as they will be located in their neighborhood. A clear-cut answer is probably non-existent. Several effective programs enacted in unison is the only option that can stop the growing mounds of trash that are piling up around the country.