Recycling
Recycling
|I | |INTRODUCTION |
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Overflowing Landfill
An average city dweller may produce a ton of refuse in a year, a volume that rapidly overflows local dumps. Cities running out of space for landfill often turn to incinerating their waste or transporting it to other areas, although up to 90 percent of the material might have been recycled.
Rafael Macia/Photo Researchers, Inc.
Recycling, collection, processing, and reuse of materials that would otherwise be thrown away. Materials ranging from precious metals to broken glass, from old newspapers to plastic spoons, can be recycled. The recycling process reclaims the original material and uses it in new products.
In general, using recycled materials to make new products costs less and requires less energy than using new materials. Recycling can also reduce pollution, either by reducing the demand for high-pollution alternatives or by minimizing the amount of pollution produced during the manufacturing process. Recycling decreases the amount of land needed for trash dumps by reducing the volume of discarded waste.
Recycling can be done internally (within a company) or externally (after a product is sold and used). In the paper industry, for example, internal recycling occurs when leftover stock and trimmings are salvaged to help make more new product. Since the recovered material never left the manufacturing plant, the final product is said to contain preconsumer waste. External recycling occurs when materials used by the customer are returned for processing into new products. Materials ready to be recycled in this manner, such as empty beverage containers, are called postconsumer waste.
|II | |TYPES OF MATERIALS RECYCLED |
Just about any material can be recycled. On an industrial scale, the most commonly recycled materials are those that are used in large quantities—metals such as steel and aluminum, plastics, paper, glass, and certain chemicals.
|A | |Steel |
There are two methods of making steel using recycled material: the basic oxygen furnace (BOF) method and the electric arc furnace (EAF) method. The BOF method involves mixing molten scrap steel in a furnace with new steel. About 28 percent of the new product is recycled steel. Steel made by the BOF method typically is used to make sheet-steel products like cans, automobiles, and appliances. The EAF method normally uses 100 percent recycled steel. Scrap steel is placed in a furnace and melted by electricity that arcs between two carbon electrodes. Limestone and other materials are added to the molten steel to remove impurities. Steel produced by the EAF method usually is formed into beams, reinforcing bars, and thick plate.
Approximately 64 percent of all steel is recycled, making it one of the world’s most recycled materials. In 2000 31 billion steel cans, weighing 2.4 million metric tons (2.6 million U.S. tons), were used in the United States, of which 58.4 percent were recycled. In 2000 more than 60 million metric tons (70 million U.S. tons) of scrap steel were recycled in the United States.
|B | |Aluminum |
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Recycling Plant
Many products may be made using recycled materials at less cost and with less pollution. Materials that can be recycled include metal, plastic, paper, and glass. One commonly recycled item, aluminum cans, are shown here being formed into a large block that will be shipped to another facility for reprocessing.
Roberto Soncin Gerometta/PNI
Recycling aluminum in the United States provides a stable, domestic aluminum supply amounting to approximately one-third of the industry’s requirement. In contrast, most of the ore required to produce new aluminum must be imported from Jamaica, Australia, Surinam, Guyana, and Guinea. About 2 kg (about 4 lb) of ore, a mixture of aluminum oxides called bauxite, are needed to make 0.5 kg (1 lb) of aluminum.
The U.S. aluminum industry has recognized the advantage of a domestic aluminum supply and has established systems for collection, transportation, and processing. For this reason, aluminum cans almost always produce a profit in community recycling programs. A number of states require deposits for beverage containers and have established redemption centers at supermarkets. The overall recycling rate of all forms of aluminum is about 35 percent.
Cans brought to collection centers are crushed, baled, and shipped to regional mills or reclamation plants. The cans are then shredded to reduce volume and heated to remove coatings and moisture. Next, they are put into a furnace, melted, and formed into ingots, or bars, weighing 10,000 kg (30,000 lb) or more. The ingots go to another mill to be rolled into sheets. The sheets are sent to a container plant and cut into disks from which new cans are formed. The cans are printed with the beverage makers’ logos and are shipped (with tops separate) to the filling plant.
About 100 billion aluminum beverage cans are used each year in the United States and about 55 percent of these are then recycled. The average aluminum can in the United States contains more than 50 percent postconsumer recycled aluminum. About 97 percent of all soft drink cans and 99 percent of all beer cans are made of aluminum.
|C | |Plastics |
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Sorting Plastics
Many plastic products are marked to help consumers tell which plastics can be recycled. Collecting, sorting, and recycling plastics is an expensive process. Although automated plastic sorting machines are being developed, many recycling operations sort plastic by hand, as shown here. Only 4.7 percent of plastic products in the United States are reused.
Phil Degginger/Tony Stone Images
Plastics are more difficult to recycle than metal, paper, or glass. One problem is that any of seven categories of plastics can be used for containers alone. For effective recycling, the different types cannot be mixed. Most states require that plastic containers have identification codes so they can be more easily identified and separated. The code assigns a particular number to each of the seven plastics used in packaging. The number 1 refers to polyethylene teraphthalate (PET) and the number 2 refers to high-density polyethylene (HDPE). PET can be made into carpet, or fiberfill for ski jackets and clothing. HDPE can be recycled into construction fencing, landfill liners, and a variety of other products. Plastics coded with the number 6 are polystyrene (PS), which can be recycled into cafeteria trays, combs, and other items.
The recycling process for plastic normally involves cleaning it, shredding it into flakes, then melting the flakes into pellets. The pellets are melted into a final product. Some products work best with only a small percentage of recycled content. Other products, such as HDPE plastic milk cases, can be made successfully with 100 percent recycled content. The plastic container industry has concentrated on weight reduction and source reduction. For example, the one-gallon HDPE milk container that weighed about 120 gm (about 4.2 oz) in the 1960s weighed just 65 gm (about 2.3 oz) in 1996.
In the United States, the overall recycling of plastic was 5.4 percent in 2000, with the recycling rate of plastic containers at about 18.3 percent. Most discarded plastic is in the form of plastic containers. Plastics made up about 11 percent of the waste stream by weight in 2000.
|D | |Paper and Paper Products |
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Recycling Newspapers
Newspapers are shredded and bailed at the Dakota Recyclables Collection Center in Minnesota. The papers will be used for making recycled paper products. Mixed resource collection necessitates costly separation of paper from metal and plastics, while collection of paper alone reduces the recycling costs.
Hank Morgan/Photo Researchers, Inc.
Paper products that can be recycled include cardboard containers, wrapping paper, and office paper. The most commonly recycled paper product is newsprint.
In newspaper recycling, old newspapers are collected and searched for contaminants such as plastic bags and aluminum foil. The paper goes to a processing plant where it is mixed with hot water and turned into pulp in a machine that works much like a big kitchen blender. The pulp is screened and filtered to remove smaller contaminants. The pulp then goes to a large vat where the ink separates from the paper fibers and floats to the surface. The ink is skimmed off, dried and reused as ink or burned as boiler fuel. The cleaned pulp is mixed with new wood fibers to be made into paper again.
Paper and paper products such as corrugated board constitute about 37 percent of the discards in the United States, making it the most plentiful single item in landfills. Experts estimate the average office worker generates about 5 kg (about 11 lb) of wastepaper per month. Every ton of paper that is recycled saves about 1.4 cu m (about 50 cu ft) of landfill space. One ton of recycled paper saves 17 pulpwood trees (trees used to produce paper).
|E | |Glass |
Scrap glass taken from the glass manufacturing process, called cullet, has been internally recycled for years. The scrap glass is economical to use as a raw material because it melts at lower temperatures than other raw materials, thus saving fuel and operating costs.
Glass that is to be recycled must be relatively free from impurities and sorted by color. Glass containers are the most commonly recycled form of glass, and their colors are flint (clear), amber (brown), and green. Other glass, such as window glass, pottery, and cooking utensils, are considered contaminants because they have different compositions than glass used in containers. The recycled glass is melted in a furnace and formed into new products.
Glass containers make up 90 percent of the total glass used in the United States. The 2000 recycling rate for glass was about 23 percent. Other uses for recycled glass include glass art and decorative tiles. Cullet mixed with asphalt forms a paving material called glassphalt.
|F | |Chemicals and Hazardous Waste |
Household hazardous wastes include drain cleaners, oven cleaners, window cleaners, disinfectants, motor oil, paints, paint thinners, and pesticides. Most municipalities ban hazardous waste from the regular trash. Periodically, citizens are alerted that they can take their hazardous waste to a collection point where trained workers sort it, recycle what they can, and package the remainder in special leak-proof containers called lab packs, for safe disposal. Typical materials recycled from the collection drives are motor oil, paint, antifreeze, and tires.
Business and industry have made much progress in reducing both the hazardous waste they generate and its toxicity. Although large quantities of chemical solvents are used in cleaning processes, technology has been developed to clean and reuse solvents that used to be discarded. Even the vapors evaporated from the process are recovered and put back into the recycled solvent. Some processes that formerly used solvents no longer require them.
|G | |Nuclear Waste |
Certain types of nuclear waste can be recycled, while other types are considered too dangerous to recycle. Low-level wastes include radioactive material from research activities, medical wastes, and contaminated machinery from nuclear reactors. Nickel is the major metal of construction in the nuclear power field and much of it is recycled after surface contamination has been removed.
High-level wastes come from the reprocessing of spent fuel (partially depleted reactor fuel) and from the processing of nuclear weapons. These wastes emit gamma radiation, which can cause birth defects, disease, and death. High-level nuclear waste is so toxic it is not normally recycled. Instead, it is fused into inert glass tubes encased in stainless steel cylinders, which are then stored underground.
Spent fuel can be reprocessed and recycled into new fuel elements, although fuel reprocessing was banned in the United States in 1977 and has never been resumed for legal, political, and economic reasons. However, spent fuel is being reprocessed in other countries such as Japan, Russia, and France. Spent fuel elements in the United States are kept in storage pools at each reactor site.
|III | |REASONS FOR RECYCLING |
Rare materials, such as gold and silver, are recycled because acquiring new supplies is expensive. Other materials may not be as expensive to replace, but they are recycled to conserve energy, reduce pollution, conserve land, and to save money.
|A | |Resource Conservation |
Recycling conserves natural resources by reducing the need for new material. Some natural resources are renewable, meaning they can be replaced, and some are not. Paper, corrugated board, and other paper products come from renewable timber sources. Trees harvested to make those products can be replaced by growing more trees. Iron and aluminum come from nonrenewable ore deposits. Once a deposit is mined, it cannot be replaced.
|B | |Energy Conservation |
Recycling saves energy by reducing the need to process new material, which usually requires more energy than the recycling process. To make an aluminum can from recycled metal takes only 5 percent of the total energy needed to produce the same aluminum can from unrecycled materials, a 95 percent energy savings. Recycled paper and paperboard require 75 percent less energy to produce than new products. Significant energy savings result in the recycling of steel and glass, as well.
|C | |Pollution Reduction |
Recycling reduces pollution because recycling a product creates less pollution than producing a new one. For every ton of newspaper recycled, 7 fewer kg (16 lb) of air pollutants are pumped into the atmosphere. Recycling can also reduce pollution by recycling safer products to replace those that pollute. Some countries still use chlorofluorocarbons (CFCs) to manufacture foam products such as cups and plates. Many scientists suspect that CFCs harm the atmosphere’s protective layer of ozone. Using recycled plastic instead for those products eliminates the creation of harmful CFCs.
|D | |Land Conservation |
Recycling saves valuable landfill space, land that must be set aside for dumping trash, construction debris, and yard waste (see Solid Waste Disposal: Landfill). In the United States, each person on average discards almost a ton of municipal solid waste (MSW) per year. MSW is raw, untreated garbage of the kind discarded by homes and small businesses. Waste from industry and agriculture normally is not part of MSW, but construction and demolition wastes are. The United States has the highest MSW discard level of any country in the world.
Landfills fill up quickly and acceptable sites for new ones are difficult to find because of objections by neighbors to noise and smells, and the hazard of leaks into underground water supplies. The two major ways to reduce the need for new landfills are to generate less initial waste and to recycle products that would normally be considered waste.
In 2000 about 15 million metric tons (16.5 million U.S. tons) of food and yard debris were composted in the United States, accounting for almost a quarter of all recycling by weight. The combined effort of reducing waste and recycling resulted in 37.6 million fewer metric tons (41.4 million U.S. tons) of material going to landfills.
Solid waste can also be burned instead of buried in the ground. Typically, waste-to-energy (WTE) facilities burn trash to heat water for steam-turbine electrical generators. This WTE recycling keeps another 14.5 percent of municipal solid waste out of the landfills.
|E | |Economic Savings |
Recycling in the short term is not always economically profitable or a break-even financial operation. Most experts contend, however, that the economic consequences of recycling are positive in the long term. Recycling will save money if potential landfill sites are used for more productive purposes and by reducing the number of pollution-related illnesses.
|IV | |HISTORY |
People have recycled materials throughout history. Metal tools and weapons have been melted, reformed, and reused since they came in use thousands of years ago. The iron, steel, and paper industries have almost always used recycled materials. Recycling rates were modest in the United States up through the 1960s, although rates increased during World War II (1939-1945). Since the 1960s, recycling has steadily increased. Recycling in the United States between 1960 and 2000 rose from 5.35 million metric tons (5.9 million U.S. tons) per year to 63.4 million metric tons (69.9 million U.S. tons). In 1930 about 7 percent of municipal solid waste was recycled. By 2000 that amount had climbed to 30.1 percent.
European countries have a long history of recycling and, in some cases, stiff requirements. In 1991 the German parliament approved legislation setting recycling targets of 80 to 90 percent for packaging materials and banned the sale of products from companies that do not cooperate. France has set specific recycling goals. Other countries with significant overall recycling rates include Spain at 29 percent, Switzerland at 28 percent, and Japan at 23 percent.
Contributed By:
Roy A. Hartman
Microsoft ® Encarta ® 2007. © 1993-2006 Microsoft Corporation. All rights reserved.
Thermal Pollution
|I | |INTRODUCTION |
Thermal Pollution, harmful increase in water temperature in streams, rivers, lakes, or occasionally, coastal ocean waters. Thermal pollution is caused by either dumping hot water from factories and power plants or removing trees and vegetation that shade streams, permitting sunlight to raise the temperature of these waters. Like other forms of water pollution, thermal pollution is widespread, affecting many lakes and vast numbers of streams and rivers in the United States and other parts of the world. A temperature increase as small as 1 or 2 Celsius degrees (about 2 to 4 Fahrenheit degrees) can kill native fish, shellfish, and plants, or drive them out in favor of other species, often with undesirable effects.
|II | |MAJOR SOURCES |
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Thermal Pollution from Power Plants and Factories
Power plants and industrial factories are among the major contributors to the problem of thermal pollution. These facilities draw water from nearby lakes and streams, which they use to cool their machinery and steam-driven equipment. Although many such facilities now take care not to contaminate the water with chemical pollutants, few return the heated water to its original temperature before dumping it back into the lakes and streams from which it came. The heated water warms local bodies of water by as much as 10° C (18° F), making the water uninhabitable for fish and other organisms.
Anthony Edwards/The Image Bank
The major sources of thermal pollution are electric power plants and industrial factories. In most electric power plants, heat is produced when coal, oil, or natural gas is burned or nuclear fuels undergo fission to release huge amounts of energy. This heat turns water to steam, which in turn spins turbines to produce electricity. After doing its work, the spent steam must be cooled and condensed back into water. To condense the steam, cool water is brought into the plant and circulated next to the hot steam. In this process, the water used for cooling warms 5 to 10 Celsius degrees (9 to 18 Fahrenheit degrees), after which it may be dumped back into the lake, river, or ocean from which it came. Similarly, factories contribute to thermal pollution when they dump water used to cool their machinery.
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Deforestation and Erosion
The lush vegetation bordering lakes and streams provides a shade cover that keeps water temperatures cool. When the plants and trees are removed, sunlight shines directly on the water, raising the temperature as much as 10° C (18° F). The ensuing erosion compounds the thermal pollution because silty muddy waters absorb more energy from the sun than clear water does.
S.E. Cornelius/Photo Researchers, Inc.
The second type of thermal pollution is much more widespread. Streams and small lakes are naturally kept cool by trees and other tall plants that block sunlight. People often remove this shading vegetation in order to harvest the wood in the trees, to make room for crops, or to construct buildings, roads, and other structures. Left unshaded, the water warms by as much as 10 Celsius degrees (18 Fahrenheit degrees). In a similar manner, grazing sheep and cattle can strip streamsides of low vegetation, including young trees. Even the removal of vegetation far away from a stream or lake can contribute to thermal pollution by speeding up the erosion of soil into the water, making it muddy. Muddy water absorbs more energy from the sun than clear water does, resulting in further heating. Finally, water running off of artificial surfaces, such as streets, parking lots, and roofs, is warmer than water running off vegetated land and, thus, contributes to thermal pollution.
|III | |IMPACTS |
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Brown Trout
When thermal pollution drives water temperatures up, most aquatic and marine wildlife cannot survive. Immobile organisms, such as plants and shellfish, simply die. Animals capable of moving may leave in search of cooler waters, but even those able to find a more suitable habitat may not survive the transition. Salmonids, members of the trout and salmon family, are genetically programmed to lay their eggs in the same gravel streambeds where they themselves hatched. When thermal pollution warms streams and erosion covers the gravel bottom with a layer of silt, the fish eggs cannot survive. Such habitat degradation has caused the demise of many populations of brown trout, shown here, and other salmonids.
Hans Reinhard/OKAPIA/Photo Researchers, Inc.
All plant and animal species that live in water are adapted to temperatures within a certain range. When water in an area warms more than they can tolerate, species that cannot move, such as rooted plants and shellfish, will die. Species that can move, such as fish, will leave the area in search of cooler conditions, and they will die if they can not find them. Typically, other species, often less desirable, will move into the area to fill the vacancy.
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Cyanobacteria Growing in a Hot Spring
Bright bands of cyanobacteria, also known as blue-green algae, grow in concentric rings in the hot waters of thermal springs. Different species of cyanobacteria, each of a different color, thrive at temperatures far above those tolerated by most other forms of life. Cyanobacteria are often the only organisms able to survive in lakes and streams that have been devastated by thermal pollution. Even if other animals can survive the warmer temperatures, they will probably die as cyanobacteria take over and alter the water’s oxygen level.
Godfrey Merlen/Oxford Scientific Films
In general, cold waters are better habitat for plants and animals than warm ones because cold waters contain more dissolved oxygen. Many freshwater fish species that are valued for sport and food, especially trout and salmon, do poorly in warm water. Some organisms do thrive in warm water, often with undesirable effects. Algae and other plants grow more rapidly in warm water than in cold, but they also die more rapidly; the bacteria that decompose their dead tissue use up oxygen, further reducing the amount available for animals. The dead and decaying algae make the water look, taste, and smell unpleasant.
|IV | |CONTROLS |
Thermal pollution from power plants and factories is relatively easy to control. Instead of discharging heated water into lakes and streams, power plants and factories can pass the heated water through cooling towers or cooling ponds, where evaporation cools the water before it is discharged. Alternatively, power plants can be designed or refitted to be more efficient and to produce less waste heat in the first place. In a process called cogeneration, the excess heat energy from generating electricity can be used in another manufacturing process that needs such energy. Where homes or other buildings are located near industrial plants, waste hot water can be used for heating—an arrangement often found in Scandinavian towns and cities, and proposed for use in China.
In the United States, the problem of industrial thermal pollution was first addressed in 1970, when Congress gave the Atomic Energy Commission authority to regulate thermal pollution from nuclear power plants. In 1972, the comprehensive Clean Water Act instructed the Environmental Protection Agency to issue regulations to clean up all hot water discharges from all power plants, nuclear or conventional. Since then, thermal pollution from power plants has not been a major issue in the United States.
To prevent thermal pollution due to devegetation, the prescription is simple: do not devegetate. Landowners can leave strips of trees and vegetation along streams and shorelines. Grazing livestock can be kept away from streamsides by fencing. All efforts to control erosion also have the effect of keeping water clearer and, thus, cooler.
As a practical matter, however, thermal pollution from devegetation is quite hard to control because it is caused by the cumulative effect of many peoples’ actions, most of which are individually minor. Regulations focus on a few of the most important threats. Grazing management plans, for instance, are intended to counter thermal pollution and other problems on lands owned by the federal government. In the United States, regulations governing logging on both public and private lands supposedly protect streamsides, though enforcement is often lax. Elsewhere, streamside protection is largely up to private landowners, encouraged and aided by such advisory organizations as the federal Natural Resources Conservation Service and cooperative Resource Conservation Districts.
Contributed By:
John Hart
Microsoft ® Encarta ® 2007. © 1993-2006 Microsoft Corporation. All rights reserved.
1971: Oceanography
Activities of NOAA.
President Richard M. Nixon's new National Oceanic and Atmospheric Administration (NOAA), formed in 1970, continued organizational activities this year, and budget cutbacks resulted in belt-tightening for American oceanographers. (Inflation, money troubles in universities and colleges, increased costs of research, and government curtailment of several oceanographic programs all contributed to an economic recession in the oceanographic community.) In addition to organizational problems, NOAA was involved in national reorientation from basic exploratory research to mission-oriented oceanography. Through financial incentives, NOAA will promote programs of direct utility to the nation for utilization and protection of resources and for defense.
Contamination of animal tissue.
Hazardous levels of mercury and pesticides have prevented commercial sales of several lots of mackerel, tuna, and salmon and practically eliminated swordfish from the American diet. Heavy metals and pesticides accumulate in animal tissues, and even trace amounts of these compounds are magnified in the food chain of the sea. Predatory fish, such as tuna, receive and store contaminants accumulated by all of the organisms below them in the food chain. In areas of sewage dumping and drainage outfalls, where contamination is concentrated, levels of pesticides became alarmingly high in edible fishes.
Animals which feed on fish, such as whales, porpoises, and seabirds, have been dangerously contaminated. Samples of whale tissue have been shown to contain 7.4 to 25.9 parts per million of mercury. Investigations on the 1969 Irish seabird kill, where more than 17,000 seabirds died, were completed in 1971. There were high levels of polychlorinated biphenyls (PCB's) in the livers of these birds. PCB's are plasticizers and insulators and are similar in structure to DDT. Levels of lead, mercury, and other heavy metals were also high.
Oil pollution.
For 133 days a Shell Oil platform belched smoke, flames, and crude oil into the Gulf of Mexico. This fire, the largest and longest-lasting platform fire to date, was extinguished primarily by drilling relief wells and pumping mud into the wild wells. The U.S. government indicted and fined a number of oil companies for failure to provide storm chokes and similar subsurface shutoff devices on offshore platforms. Initial, uncontested fines against three of the companies totaled more than $500,000.
Exploratory offshore oil-drilling activities continued to spread around the world. Drilling began on continental shelves from Australia to the North Atlantic, and wells were drilled in unprecedented depths, with the Humble Oil and Refining Company completing an exploratory well in 1,497 feet of water. The oceans will probably yield more than 2 million barrels of oil in 1971. By 1985, reserves of 20 billion barrels are expected to be discovered on the U.S. continental shelves to depths of 2,000 feet. Unfortunately, estimates of oil spills and well leaks are also high—10 million metric tons by 1980.
Despite the oil companies' claim that they spent $1.5 million a day in pollution control, accidents and oil spills were frequent occurrences. Many oil spill clean-up devices were invented to combat the spreading layer of oil on the ocean surface, but the problem of locating the spills and deploying these inventions presented almost impossible logistics. Realizing that accidental and deliberate oil spills are frequent occurrences, tanker-owning oil companies in January signed a voluntary agreement to create a fund that will meet the liability for tanker pollution damage up to a total of $30 million for each incident. In April, at a NATO conference on protecting the environment, the United States announced a decision to halt all deliberate discharge of oil wastes into the sea by 1975.
Ocean dumping.
In February concern that ocean dumping of solid wastes might lead to ecological problems prompted the Department of Defense to place a moratorium on ocean dumping of tactical supplies, such as nerve gas, until further studies are made. Delaware and New Jersey took measures to prevent ocean dumping off their shores, and Delaware legislated against continued development of heavy industry along its coastline. The Environmental Protection Agency sponsored several waste disposal programs, including one which investigated the use of compacted wastes as artificial reefs.
Pollution control programs.
The National Science Foundation provided $3 million funding for the International Decade of Ocean Exploration's Geochemical Ocean Sections Study. This program will establish standards to which future experimental data can be compared in such areas as radiation pollution and ocean mixing. Standardized measurements will enable future researchers to detect changes in these critical parameters. Preliminary tests were conducted in the Pacific, and major expeditions will be undertaken to the Atlantic, Indian, Pacific, and Antarctic oceans in 1972.
Coupled with programs to gather standardized measurements is NOAA's planned global network of intercommunicating buoys. This program, entitled the National Data Buoy Program, will utilize knowledge gained by the Monster Buoy Program in construction of deep-sea, moored buoys with oceanographic and meteorological sensors. Environmental data collected by the buoys will be relayed by satellite to a central oceanographic computer bank in the United States. This year contracts were let for construction of test instrument packages and buoy platforms.
Buoys for near-shore pollution control have been developed and put into use. In August the Environmental Protection Agency's National Marine Water Quality Laboratory in Rhode Island relayed environmental parameters from a subsurface buoy in Narragansett Bay to a control display at the Marine Technological Society conference in Washington, D.C. Real-time data were available and the buoy could be interrogated by telephone hookup.
Research projects and results.
Scientists at the National Institute of Oceanography in Great Britain discovered the function of an enigmatic organ in the nose of sperm whales and some related porpoises. This organ contains a substance known as spermaceti. By regulating blood flow to the organ, the animal's body adjusts the temperature of the spermaceti. At 84°F it solidifies and contracts about 5 percent, adding about 200 pounds of negative buoyancy. The spermaceti organ thus gives the whale a sensitive buoyancy control to aid descent, ascent, and submerged swimming orientation.
The research vessel Glomar Challenger continued its worldwide expeditions. Among its accomplishments was reentry into a bore hole in 13,000 feet of water in the Caribbean. Although the system was proved the previous year, this was the first time it was used to collect samples otherwise unobtainable. After a hole was drilled 2,300 feet into the earth's crust, a layer of chert (a flint-like rock) dulled the tungsten carbide bit. The bit was withdrawn from the hole and repaired. After one miss, the crew maneuvered the new bit back into the casing and resumed drilling to basalt sediment that was more than 45 million years old. The presence of this igneous rock may cause revision of theories of the age of the Caribbean. From the Caribbean, the Glomar Challenger moved to the Pacific to investigate sea-floor spreading, prehistoric climatic changes, and earthquake zones.
In September, the Atlantic Oceanographic Laboratory of NOAA deployed sea-floor tide gauges in 2,400 to 2,600 fathoms of water south of Puerto Rico. Previously, measurements of ocean tides were made only by shore stations. Even on small islands, submerged topography influences the tides, confusing correlation of ocean tides with lunar and solar movements. The delicate pressure sensors record open ocean tides for one month and float back to the surface when released by a sonic trigger.
Scientists at the Makapuu Oceanic Institute in Hawaii made a major breakthrough in marine aquaculture. By means of hormones and controlled environmental conditions, mullet were cultured through a complete life cycle, including maturation and spawning. Though many marine organisms have been reared in captivity, this was the first time a full biological cycle was completed in a manner suitable for commercial aquiculture. Hatchery-controlled culture of mullet may provide a significant new protein source for underdeveloped countries.
Man in the sea.
Submersible activity decreased this year with several of the more prominent research submersibles, including the Aluminaut, retiring from active duty. The U.S. Navy's first Deep Submergence Rescue Vehicle (DSRV-1) made a dive to the design depth of 3,500 feet, and a second DSRV was commissioned.
An important innovation in submersibles was the development and use of acrylic spheres as pressure hulls. The Johnson-Sea-Link, commissioned in Florida in January, features a two-man transparent acrylic sphere which gives panoramic underwater visibility. The 7-meter-long vessel can operate at a depth of 1,200 feet indefinitely and has a three-man aluminum lock-in/lock-out compartment.
An increasing number of subsea habitats were put into use. Tektite 2, the habitat which supported a multitude of scientists in the Virgin Islands in 1970, was moved to Texas, where it will become the first national continental-shelf station. The Perry Hydrolab began continuous operations off Grand Bahama in March. The U.S. Navy has placed Sea Lab 1 off Panama City, Fla., in 65 feet of water. NOAA organized a series of scientific programs using the mobile habitat Edalhab off the Florida Keys, and Canada continued its activities with the Sublimnos habitat. Japan, Germany, and the Soviet Union were also conducting habitat operations this year.
Diving exploration under arctic ice highlighted the man-in-the-sea programs this year. U.S. Navy oceanographers dove 800 kilometers from the north pole during the arctic night. The MacInnis Foundation also dove in Resolute Bay in Canada, only 160 kilometers from the magnetic pole. Dives of two to three hours demonstrated man's ability to work effectively in the polar seas. The underside of the 15-to-60-foot-thick ice pack was surveyed and photographed, and divers collected samples of organisms growing under the ice. The water was exceedingly clear with visibility up to 150 feet.
Microsoft ® Encarta ® 2007. © 1993-2006 Microsoft Corporation. All rights reserved.
Oil spills and fires plagued offshore drilling operations throughout the year. A massive oil fire erupted in the Gulf of Mexico on February 19, when a storm tipped over a giant oil rigging platform which the Chevron Oil Company had erected on the outer continental shelf. Nearly 1 million gallons of crude oil gushed into the waters before the fire was completely put out on March 19 and before all the leakage was able to be stopped on March 31. The company was found to have violated many pollution control regulations and was fined $1 million. On December 1 a Shell Oil Company platform in the Gulf of Mexico near Louisiana exploded, killing four men. The oil that gushed from the 22 wells caused massive fires and left a slick estimated to be 3 miles long and 1ψ miles wide. Nevertheless, sales of the leases to permit offshore drilling, halted for two years because of disasters, resumed in December.
Mercury, a pollutant that has been fouling waterways for years, was discovered, almost overnight, to be at dangerous levels in the rivers, lakes, fish, and wildlife of at least 33 states. Mercury is discharged in the wastes from chemical, paper, and other manufacturing plants and collects in the bottoms of rivers and lakes. The discharged mercury, harmless in its organic form, changes its potency in water and is transferred into methyl mercury, a deadly poison that kills human brain cells. The deadly mercury enters the food chain when it is absorbed by microorganisms in the water and eventually reaches human beings who eat poisoned fish. Mercury that is already in the water can remain in its methyl state for 50 to 100 years.
Serious attention was given to the pollutant in March, when Canadian officials discovered contaminated fish in the St. Clair and Detroit rivers, which flow into Lake St. Clair and Lake Erie. Canada banned all fishing in these waters in March, and Ohio forbade commercial fishing in Lake Erie.
In August and September mercury pollution was reported in game birds in Michigan, North Dakota, and Idaho. The Department of the Interior reported in July that mercury poisoning was the cause of death in some bald eagles. In October the Food and Drug Administration recalled 10,000 pills that had been made from the livers of contaminated seals, some caught as far away as the Pribilof Islands off Alaska. As a precautionary measure, in December the FDA ordered off the market 1 million cans of tuna fish suspected of being contaminated. The brands considered to contain more mercury than specified by FDA guidelines are certain lots of Bumble Bee, Chicken of the Sea, Empress, Grand Union, Orchard Park, Star Kist, and Van Camp. This was the first time ocean fish were found to contain high levels of mercury. Later in the month the FDA asked for voluntary removal from the market of frozen swordfish found to contain dangerous levels of mercury.
Widespread pollution of the oceans was reported during the year. In February it was revealed in a report by the U.S. Marine Laboratory of Sandy Hook, N.Y., that the millions of tons of sewage sludge and dredging spoils that had been dumped over the years about 12 miles from the New Jersey and New York shoreline had polluted the ocean to such an extent that no marine life could live there.
Air pollution.
During the week beginning July 26, the eastern seaboard experienced an air pollution crisis of the sort now commonplace in Los Angeles. From Boston to Atlanta eyes smarted and people breathed heavily as a gray pall of polluted air was held close to the ground by a temperature inversion.
On August 3 the National Air Pollution Control Administration released a list ranking U.S. cities with the worst sulfur oxide levels; New York, Chicago, Huntington, W.Va., Philadelphia, Pittsburgh, Cleveland and St. Louis (tied), Washington, D.C., Detroit, and Providence held the top ten positions.
An emergency smog alert system was set up in Tokyo on July 27 during a week of severe smog caused by a combination of ultraviolet rays from the sun, exhaust fumes from cars, and sulfur dioxide emitted from factories burning heavy oil. In five days an estimated 8,000 people sought treatment at hospitals for sore eyes and throats, and residents were warned to stay indoors during the worst of the alert. Air and water pollution problems have been reported in Sydney, Santiago, Buenos Aires, Rome, and Athens. The Soviet Union admitted pollution problems caused by industrial wastes, especially in the Ural River. West Germany and the Netherlands had a conference during the year to determine ways to clean up their rivers.
Preventive measures.
On August 14, the U.S. Department of Agriculture canceled sales of 48 mercury compounds for industrial use, and by late September the secretary of the interior announced that industrial mercury discharges into the waterways had been cut by 86 percent. The National Environmental Policy Act of 1969, signed into law on January 1, created the three-member Council on Environmental Quality to develop national environmental policy, to coordinate the activities of the diverse groups handling environmental programs, and to ensure that those federal agencies which pollute and deteriorate the environment state the reasons for the necessity of such actions. In April, President Nixon signed the Water Quality Improvement Act, which sharply increased the penalties for oil spills and extended the violator's liability for clean-up operations to $14 million. The federal Environmental Protection Agency, created on December 2, consolidated previously scattered federal programs controlling water, air, solid wastes, pesticides, and radiation into one agency.
Steps were taken to protect the environment in Illinois, New York, New Jersey, Washington, Vermont, and Maine. In June the Michigan legislature approved a bill that guaranteed easy access to the courts for private citizens to sue polluters or state governmental agencies not doing an adequate clean-up job. Canada banned in August the manufacture of laundry detergents having a phosphate content over 20 percent. In November the Suffolk County, N.Y., legislature passed a law banning the sale of all detergents in the county except those used in shampoo, dishwashing powder, and toothpaste. The law will become effective March 1, 1971. Chicago banned phosphate detergents in November. In May the Soviet Union forbade the production of DDT and restricted its use.
To examine the problems of the world's environment, the United Nations called a world conference on the human environment, to be convened in Sweden in June 1972. Preparatory conferences were held this year, including a month-long July meeting of scientists at Williamstown, Mass., to focus on changes in the world's climate and on ecological upsets. The scientists fear the increased carbon dioxide in the atmosphere—.2 percent more a year since 1958 as a result of burning coal, oil, and gas—will raise the temperature of the earth, upsetting food production, water levels, and the balance of life.
Citizens in court.
Environmental lawsuits succeeded in delaying or halting some resource exploitation projects. In late January the federal government, under pressure from conservation groups, arranged with Florida authorities to ban construction of a jetport in the Everglades which would have endangered the ecological balance of the national park there. In April the proposed 800-mile oil pipeline from the Arctic to southern Alaska was postponed after conservation groups maintained that an underground pipeline carrying 180°F oil could cause dangerous melting of the permanent frozen layer below the earth's surface. The Environmental Defense Fund secured a May 31 court ruling ordering Secretary of Health, Education, and Welfare Robert Finch to begin taking steps leading to a ban on DDT in raw agricultural commodities. The U.S. Department of Agriculture banned the sale of DDT for use on over 50 food crops. Cotton, accounting for over 70 percent of the use of the insecticide, was exempted.
Public-interest law firms prosecuting these and similar cases were endangered when the Internal Revenue Service announced in October that it was considering withdrawing the tax-exempt status of these groups, a feature often thought necessary for the successful financing of public-interest organizations. However, under pressure, this move was averted in November.
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