UNIT-4
Environmental Pollution
It is the introduction of contaminants into the environment that makes the environment unhealthy for habitation and in the extreme can harm the ecosystem. Or it can be defined as contamination of the environment by man-made substances or energy that has adverse effects on living or non-living matter. Simply said, pollution can be seen as the wrong substance in the wrong place in the wrong quantities at the wrong time. This implies that harm is caused to the environment if the same substance is present at levels too low.
Air pollution is the contamination of the atmosphere by gaseous, liquid, or solid wastes or by-products that can endanger human, animal, and plant health or can attack materials, reduce visibility and produce undesirable odors.
(a) Causes of air pollution:
Major air pollutants are
• Carbon monoxide
• Carbon dioxide
• Ozone
• Chlorofluorocarbons (CFCs)
• Sulfur compounds: Sulphur dioxide, Hydrogen sulfide.
• Nitrogen oxides: Nitrous oxide, Nitric oxide, Nitrogen dioxide, Acid rains
(b) Effects of air pollutions:
Air pollution affects the vegetation, human health, and materials in different ways as described below
Effect on vegetation:
• The most damage caused by air pollution to vegetation is on leaf structure.
• Nitrogen dioxide is highly injurious to plants. It suppresses growth when plants are exposed to 0.3 to 0.5 ppm for 10 to 20 days.
• Sulfur dioxide causes reduced enzymatic activity, suppression of photosynthesis, and other metabolic activities; chorus injury causes reduced crop yield and death of plants.
• Acid rain washes away essential nutrients that the plants in need. It makes the soil acidic and helps the release of aluminum and copper ions, harmful to plants.
Effects on human health: A person can survive for five weeks without food, five days without water, and only five minutes without air hence, the air we breathe must be of good quality.
• Carbon monoxide (Co) is a poisonous gas on account of having an affinity of hemoglobin, the red pigment that carries oxygen in the blood.
• Sulfur dioxide irritates the respiratory system.
• Nitrogen dioxide penetrates smaller airways and lung parenchyma.
• Hydrocarbons may cause cancer in human beings.
• Hydrogen sulfide causes headaches, conjunctivitis, sleeplessness, and pain in the eyes. High concentration can lead to blockage of O2 transfer and damaged nerve tissues.
• Mercury emitted from mining and refining of mercury causes profuse diarrhea, kidney lesions, a disorder of cardiac function, and neurological function.
• Ethylene with nitrogen oxide and ozone causes eye irritation. Ethylene is found in the emission of motor vehicles, chemical industries, and growing plants.
• Chlorine is also irritating to the eye, nose, and throat. It is sometimes used in swimming pools as a disinfectant.
• Boron causes damage to the central nervous system and death.
Effect on materials: Air pollution damage the property of metals such as corrosion of metals, soiling and eroding of building surfaces, fading of dyed materials, wooden cracking, etc.
(c) Air pollution control:
Air pollution is a major threat to our environment. Every man must fight against it. A man should change him “out of sight is out of mind concept”. Air pollutants are mainly particulate matter, gaseous emission, and automobile exhaust. There are different techniques to control the above pollution.
Particulate control technique: Particulates present in the air in the form of aerosol, dust, mist, smoke, smog, or cloud pose a potential pollution hazard. There are various broad approaches for the control of particulates like dilution in the atmosphere, Control equipment, etc.
Control of gaseous pollutants: Sulphur oxides, nitrogen oxides, carbon oxides, carbon dioxides, organic acid gases, and hydrocarbons are the principal acidic gases responsible for air pollution. For the control of these gases, the mechanisms are chemical engineering, condensation, and combustion.
Automobile emission control: Automobile emissions are the major problem of metropolitan cities. It can be controlled by-
• Control of evaporation emissions.
• Control of exhaust emission.
• Control of crankcase emission.
• Gasoline engine emission control.
• Strict implementation of legislation.
The environmental problems in India are growing tremendously day by day. The increasing economic development and a rapidly growing population that has taken the country from 300 million people in 1947 to more than one billion people today is putting a strain on the environment, infrastructure, and the country’s natural resources. Industrial pollution, soil erosion, deforestation, rapid industrialization, urbanization, and land degradation contribute towards worsening the problems. Overexploitation of the country's resources, be it land or water and the industrialization process has resulted in the environmental degradation of resources. Environmental pollution is one of the most serious problems facing humanity and other life forms on our planet today.
India's per capita carbon dioxide emissions were roughly 3,000 pounds (1,360 kilograms) in 2007, according to the study. That's small compared to China and the U.S., with 10,500 pounds (4,763 kilograms) and 42,500 pounds (19,278 kilograms) respectively that year. The study shows that the European Union and Russia also have more emissions as compared to India.
A recent report by MIT researchers says that the harmful pollutants emitted by an aircraft at an altitude of 35,000ft are fatal for people
The brilliant white of the Taj Mahal is slowly fading to a sickly yellow. In the famous “Taj mahal Case” a very strong step was taken by Supreme Court to save the Taj Mahal. Case being polluted by fumes and more than 200 factories were closed down.
Water pollution is the contamination of water by foreign matter such as microorganisms, chemicals, industrial wastes, or sewage. Such matters deteriorate the quality of water and make it unfit for human, animal, and plant use. When waste products and materials causing contamination are released into river drainage systems and other water bodies, the water becomes unfit or the quality of the water for use by man or habitation gets compromised. This is known as water pollution.
(a) Causes of water pollution:
• Organic wastes.
• Fertilizers and detergents.
• Sediments consisting of soil and mineral particles, flooded water, etc.
• Radioactive substances from mining and refining, industries, medical and scientific uses.
• Heavy metals, inorganic minerals, etc.
• Mineral oils.
• Biocides, herbicides, pesticides, etc.
• Sewage, domestic, wastes.
• Industrial wastes.
Increased temperature due to discharge of cooling water by factories and power plants.
(b) Effect of water pollution: Polluted water will affect human health, soil health, and plant health or growth, quality of water, etc.
Effect on soil health: Use of polluted water as irrigation, resulted in deterioration of soil health like microorganisms in soil decreases in number, it also affects adversely on soil Physical and chemical properties which reduce crop yield.
Effect on human health: Water sustains life. It carries many microorganisms, parasites, and dust, which are taken up by human beings and animals; nitrate in drinking water can cause death to children (infants). Polluted drinking water carries organisms of many diseases of human beings.
Effects on plant health:
• Eutrophication occurs when lake water becomes artificially enriched with nutrients causing abnormal plant growth.
• Run-off of chemical fertilizer from cultivated fields may decrease plant health.
• The process of eutrophication can produce esthetic problems (bad taste and smell), oxygen depletion in deeper waters, and other chemical changes that affect badly on plant growth.
Effects on water quality:
• The contamination of water supplies with sewage caused major epidemics of typhoid and cholera in Britain and Europe.
• Organic compounds can adversely affect the taste of water.
• Most of the disease-causing bacteria enter the body of animals and human being through water and develop serious diseases.
• Water pollution by domestic sewage and discharges from hospitals and slaughterhouses are the sources of pathogens causing infectious diseases.
(c) Control of water pollution: The various ways/techniques for prevention and control of water pollution are:
• Stabilization of ecosystem
• Reutilization of wastes
• Recycling of wastes
• Removal of pollutants
• Enforcement of rules strictly
• Treatment of sewage water with physical, chemical, or biological processes for organic matter.
Soils are an integral part of the regulation process of pollutants in ecosystems. Soil is an important source of pollution in and itself a carrier of pollutants. Soil is an important link for pollutants through precipitation, sorption, and immobilization reactions. A massive increase in agricultural and industrial activities resulted in extensive degradation of the soil environment. Soil is the mother of living organisms. Contamination occurs when chemicals are released by spill or underground leakage. Among The most significant soil contaminants are hydrocarbons, heavy metals, herbicides, pesticides, and chlorinated hydrocarbons.
(a) Causes of soil pollution: A wide range of agrochemicals (fertilizers and pesticides) is currently used by farmers to sustain food production. Today, over one lakh chemicals including insecticides, pesticides, fungicides, herbicides, acaricides, and rodenticides are in use thought the world for pest-weed control.
a) Agrochemicals: (1) Pesticides, (2) Insecticides, (3) Herbicides, (4) Fungicides, (5) Fertilizers
b) Industrial wastes: (1) Effluents, (2) Dust and other waste (3) Radioactive wastes, (4) Heavy metals (5) Acid precipitation
c) Urban wastes: (1) Municipal solid waste, (2) Municipal Sewage (3) Vehicular exhaust
d) Rural wastes: (1) Home wastes (2) Litter (3) Livestock wastes (4) Plant residues (5) Sediments
(b) Effect of soil pollution: Pollution of soil reduces soil quality, fertility, and water holding capacity. A large proportion of acid soils have arisen from the indiscriminate use of fertilizers. The use of pesticides causes the death of useful and beneficial microorganisms and soil organisms, making the soil hard and infertile. Application of N fertilizers such as urea and ammonium sulfate to soils produces acid.
(c) Control of soil pollution: Eco-friendly farming systems is the only approach to control soil pollution. There are several approaches to these systems, they are; organic farming; biological farming, natural farming, alternate agriculture, regenerative agriculture, perm culture, ecological agriculture, ecological farming system, integrated intensive farming system (IIFS), low external input supply agriculture (LEISA).
Oceans are the largest water bodies on Earth. Over the last few decades, excessive human activities have severely affected marine life on the Earth’s oceans. Ocean pollution or marine pollution is the spreading of harmful substances such as plastic, oil, industrial and agricultural waste, and chemical particles into the ocean.
Since oceans are home to a wide variety of marine animals and plants, every citizen should be responsible and work in making these oceans clean so that marine species can thrive for a longer period.
One of the major sources of contamination in the ocean is the mining of materials such as copper and gold. For example, copper is a major source of pollutants in the ocean and can interfere with the life cycles of numerous marine organisms and life.
According to National Geographic,
“Many ocean pollutants are released into the environment far upstream from coastlines. Nitrogen-rich fertilizers applied by farmers inland, for example, end up in local streams, rivers, and groundwater and are eventually deposited in estuaries, bays, and deltas. These excess nutrients can spawn massive blooms of algae that rob the water of oxygen, leaving areas where little or no marine life can exist.”
Various Causes of Ocean Pollution
There are many ways in which pollution enters the ocean. Some of them are:
• Sewage
Pollution can enter the ocean directly. Polluting substances flow through sewage lines, rivers, or drainages which are dumped directly into the ocean. This is often how minerals and substances from mining camps find their way into the ocean.
The release of other chemical nutrients into the ocean’s ecosystem leads to reductions in oxygen levels, the decay of plant life, and a severe decline in the quality of the seawater itself. As a result, all levels of oceanic life, plants, and animals are highly affected.
• Toxic Chemicals from Industries
Industrial and agricultural waste is another most common form of wastes that is directly released into the oceans, thus polluting the ocean.
When toxic liquids are dumped in the ocean directly, it affects marine life. They are hazardous and they raise the temperature of the ocean, a phenomenon known as thermal pollution, as the temperature of these liquids is quite high. Animals and plants that cannot survive at higher temperatures eventually perish.
• Land Runoff
Land runoff is another source of pollution in the ocean. This occurs when water infiltrates the soil to its maximum extent. The excess water from rain, flooding, or melting flows over the land and meets the ocean.
Often, this water picks up man-made, harmful contaminants that pollute the ocean, including fertilizers, petroleum, pesticides, and other forms of soil contaminants. Fertilizers and waste from land animals and humans can cause damage to the ocean by creating dead zones.
• Large Scale Oil Spills
Ship pollution is a huge source of ocean pollution, the most devastating effect of which is oil spills. Crude oil may float on the sea for years and it is extremely toxic to marine life, often suffocating marine animals to death once it entraps them. Crude oil is also extremely difficult to clean up. This means that when it is spilled, it is usually there to stay.
Thousands of crates are lost each year from ships due to storms, emergencies, and accidents. This results in noise pollution (excessive, unexpected noise that interrupts the balance of life, most often caused by modes of transportation), excessive algae, and ballast water.
Often, other species can also invade an ecosystem and harm it by interrupting the life cycles of other organisms, causing a clash of nature that has already been damaged by the overflow of pollution.
• Ocean Mining
Ocean mining in the deep sea is another source of ocean pollution. Ocean mining sites are drilled for silver, gold, copper, cobalt, and zinc, etc. These create sulfide deposits up to three and a half thousand meters down into the ocean.
While we yet to have the gathering of scientific evidence to fully explain the harsh environmental impacts of deep-sea mining, we do have a general idea that deep-sea mining causes damage to the lowest levels of the ocean and increases the toxicity of the region. The permanent damage incurred also result in leakage, corrosion, and oil spills that only drastically further hinder the ecosystem of the region.
Devastating Effects of Ocean Pollution
• Effect of Toxic Wastes on Marine Animals
An oil spill is very dangerous for marine life. The oil spilled in the ocean could get on the gills and fins of marine animals, which makes it difficult for them to move properly or feed their children. The long-term effect on marine life can include cancer, failure in the reproductive system, behavioural changes, and even death.
• Disruption to the Cycle of Coral Reefs
Oil spilled floats on the surface of the water and prevents sunlight from reaching marine plants and hampers the process of photosynthesis. Skin irritation, eye irritation, lung and liver problems can impact marine life over a long time.
• Depletes Oxygen Content in Water
Most of the debris in the ocean does not decompose and remains in the ocean for years. It uses oxygen as it degrades. As a result of this, oxygen levels go down. When oxygen levels go down, the chances of survival of marine animals like whales, turtles, sharks, dolphins, penguins for a long time also goes down.
• Failure in the Reproductive System of Sea Animals
Industrial and agricultural wastes contain various poisonous chemicals that are considered hazardous for marine life. Chemicals used in pesticides can accumulate in the fatty tissue of animals, leading to failure in their reproductive system.
• Effect on Food Chain
Chemicals used in industries and agriculture get washed into the rivers and from there are carried into the oceans. These chemicals do not get dissolved and sink at the bottom of the ocean. Small animals consume these chemicals and are later eaten by large animals, which in turn affects the whole food chain.
• Effects on Human Health
Animals from the impacted food chain are then eaten by humans, which affects their health as toxins from these contaminated animals get deposited in the tissues of people and can lead to cancer, birth defects, or long-term health problems.
Solutions to Ocean Pollution
Ocean pollution is a very big problem and it needs to be solved as early as possible. With the world’s oceans getting polluted, the marine ecosystems are getting severely disturbed.
The world’s water reserves are also becoming limited. In these situations, we must find ways of solving ocean pollution. Some of the ways are as follows:
• Reducing the Use of Plastic Products
Plastic wastes form the largest portion of ocean pollutants. Out of the 260 million tons of plastic produced each year globally, approximately 10% ends up in the oceans.
These plastics then take thousands of years to decompose, during which time they possess a terrible threat to life in the oceans. Thus, a reduction in the use of plastic products could help in significantly reducing the rates of ocean pollution.
• Use Reusable Bottles and Cutlery
Use and throw bottles and cutlery are large contributors to causing ocean pollution. Most of the non-reusable bottles and cutlery are made out of either plastic or Styrofoam. Both these materials require a few hundred or thousand years to decompose.
A plastic bottle would require about 450 years to decompose completely. In the meanwhile, it would remain inside the ocean, releasing toxins that would poison the marine life.
• Recycle Whatever You Can
The 3 R’s are the savior of ocean health. With the increase in population, the waste produced has also increased significantly. As finding dumping grounds becomes difficult, a lot of the wastes are dumped in ocean beds. These wastes that are dumped in the ocean remain there for a long time, affecting marine life.
One should check if something is recyclable before throwing it away. Then the products that can be recycled can be taken to the recycling center nearby.
• Stop Littering the Beach, and Start Cleaning It
The beach is undoubtedly one of the loveliest places to visit and hang out in. As a result of this, there is a lot of littering around as well. The first and foremost thing that needs to stop is this. Abundant dustbins should be placed on the beaches.
If someone is seen littering, they must be reprimanded immediately, and strict rules and regulations must be followed at all times. If the beach seems untidy, we could pick up the wastes and throw it in the dustbin.
• Reducing the Use of Chemical Fertilizers
Runoffs, too, pollute the oceans immensely. To prevent this, the usage of chemical fertilizers must be controlled. It must be kept in mind that excessive use of chemical fertilizers harms the soil, the water bodies nearby, and, ultimately, the ocean. These runoffs are so toxic that they can very easily kill marine life.
• Reducing the Energy Use
As the population increases, the energy demand also increases. A major amount of energy is produced from petroleum. This petroleum is obtained by the drilling of the ocean beds. Any spillage during the procedure could harm marine life. Not only that, but the procedure itself also violates the marine ecological balance. So, by controlling our energy use, we could also solve the problem of ocean pollution.
Noise pollution is can be defined as regular exposure to elevated sound levels that may lead to adverse effects in humans or other living organisms. According to the World Health Organization, sound levels of intensity less than 70 dB are not damaging to living organisms, regardless of how long or consistent the exposure is. Exposure for more than 8 hours to constant noise beyond 85 dB may be hazardous. If you work for 8 hours daily near a busy road or highway, you are very likely exposed to traffic noise pollution around 85dB.
This type of pollution is so omnipresent in today’s society that we often fail to even notice or recognize it anymore:
- street traffic sounds from cars, buses, pedestrians, ambulances, etc.
- construction sounds like drilling or other heavy machinery in operation
- airports, with constant elevated sounds from air traffic, i.e. planes taking off or landing
- workplace sounds, often common in open-space offices
- constant loud music in or near commercial venues
- industrial sounds like fans, generators, compressor, mills
- train stations traffic
- household sounds, from the television set to the music playing on the stereo or computer, vacuum cleaners, fans and coolers, washing machines, dishwashers, lawnmowers, etc.
- events involving fireworks, firecrackers, loudspeakers, etc.
- conflicts generate noise pollution through explosions, gunfire, etc.
Diseases Caused by Noise Pollution
Whether we realize it or not, noise pollution can be hazardous to our health in various ways.
- Hypertension is, in this case, a direct result of noise pollution caused by elevated blood levels for a longer time.
- Hearing loss can be directly caused by noise pollution, whether listening to loud music in your headphones or being exposed to loud drilling noises at work, heavy air or land traffic, or separate incidents in which noise levels reach dangerous intervals, such as around140 dB for adult or 120 dB for children.
- Sleep disturbances are usually caused by constant air or land traffic at night, and they are a serious condition in that they can affect everyday performance and lead to serious diseases.
- Child development. Children appear to be more sensitive to noise pollution, and many noise-pollution-related diseases and dysfunctions are known to affect children, from hearing impairment to psychological and physical effects. Also, children who regularly use music players at high volumes are at risk of developing hearing dysfunctions. In 2001, it was estimated that 12.5% of American children between the ages of 6 to 19 years had impaired hearing in one or both ears
- Various cardiovascular dysfunctions. An increase in blood pressure level caused by noise pollution, especially during the night, can lead to various cardiovascular diseases.
- Dementia isn’t necessarily caused by noise pollution, but its onset can be favored or compounded by noise pollution.
- Psychological dysfunctions and noise annoyance. Noise annoyance is a recognized name for an emotional reaction that can have an immediate impact.
Effects of Noise Pollution on Wildlife and Marine Life
Our oceans are no longer quiet. Thousands of oil drills, sonars, seismic survey devices, and shipping vessels are now seen on our waters, and this is a serious cause of noise pollution for marine life. The most affected amongst them are whales, as their hearing helps them orient themselves, feed, and communicate. Noise pollution thus interferes with cetaceans’ (whales and dolphins) feeding habits, reproductive patterns, and migration routes, and can even cause hemorrhage and death.
Other than marine life, the effects of noise pollution are also seen on land animals. They are affected by noise pollution in the form of traffic, firecrackers, etc., and birds are especially affected by the increased air traffic.
Social and Economic Costs of Noise Pollution
The World Health Organization estimates that one out of three people in Europe is harmed by traffic noise. Other than the medical effects of noise pollution on humans, there is a significant social and economic impact. Since noise pollution leads to sleep disturbance, it affects the work performance of an individual during the day. This may lead to hypertension and cardiovascular disease and cost additional time and money, and it negatively affects school performance in children.
Solutions for avoiding Noise Pollution
- Wear earplugs whenever exposed to elevated noise levels
- Maintain a level of around 35 dB in your bedroom at night, and around 40 dB in your house during the day
- If possible, choose your residential area as far removed from heavy traffic as you can
- Avoid prolonged use of earphones, especially at elevated sound levels
- If possible, avoid jobs with regular exposure to elevated sound levels
The presence or deposition of radioactive materials in the atmosphere or environment causes radioactive pollution. The presence, many times, is accidental and it may be an environmental threat due to radioactive decay. The destruction caused by the radioactive materials is because of the emissions of hazardous ionizing radiation (radioactive decay) like beta or alpha particles, gamma rays, or neurons in the environment.
Since the substances are characterized by radiation – because there is a lot of instability of the particles present in the radioactive materials, it can seriously affect, alter and even destroy a plant, animal, and human life. The extent of damage or danger the environment is exposed to depends upon the radioactive material concentration, the energy emitted by the radiation, proximity of the radioactive materials to those exposed, and the radiation type. Herein is a detailed explanation of the causes, effects, and solutions of radioactive pollution.
Solid waste management is a polite term for garbage management. As long as humans have been living in settled communities, solid waste, or garbage, has been an issue, and modern societies generate far more solid waste than early humans ever did.
|
Solid waste
Daily life in industrialized nations can generate several pounds of solid waste per consumer, not only directly in the home, but indirectly in factories that manufacture goods purchased by consumers.
Garbage: Many broad categories of garbage are:
- Organic waste: kitchen waste, vegetables, flowers, leaves, fruits.
- Toxic waste: old medicines, paints, chemicals, bulbs, spray cans, fertilizer and pesticide containers, batteries, shoe polish.
- Recyclable: paper, glass, metals, plastics.
- Hospital waste such as cloth with blood
1. Types & Source of Solid Wastes:
Solid waste can be classified into different types depending on their source:
|
2. Effects of Solid Waste Pollution:
Municipal solid wastes heap up on the roads due to improper disposal system. People clean their own houses and litter their immediate surroundings which affect the community including themselves.
This type of dumping allows biodegradable materials to decompose under uncontrolled and unhygienic conditions. This produces a foul smell and breeds various types of insects and infectious organisms besides spoiling the aesthetics of the site. Industrial solid wastes are sources of toxic metals and hazardous wastes, which may spread on land and can cause changes in physicochemical and biological characteristics thereby affecting the productivity of soils.
Toxic substances may leach or percolate to contaminate the groundwater. In refuse mixing, the hazardous wastes are mixed with garbage and other combustible wastes. This makes the segregation and disposal process difficult and risky.
Various types of wastes like cans, pesticides, cleaning solvents, batteries (zinc, lead, or mercury), radioactive materials, plastics, and e-waste are mixed up with paper, scraps, and other non-toxic materials that could be recycled. The burning of some of these materials produces dioxins, furans, and polychlorinated biphenyls, which have the potential to cause various types of ailments including cancer.
3. Methods of Solid Wastes Disposal:
i. Sanitary Landfill
ii. Incineration
iii. Composting
iv. Pyrolysis
i. Sanitary Land Filling:
In a sanitary landfill, garbage is spread out in thin layers, compacted, and covered with clay or plastic foam. In modern landfills the bottom is covered with an impermeable liner, usually several layers of clay, thick plastic, and sand. The liner protects the groundwater from being contaminated due to the percolation of leachate.
Leachate from the bottom is pumped and sent for treatment. When the landfill is full it is covered with clay, sand, gravel, and topsoil to prevent seepage of water. Several wells are drilled near the landfill site to monitor if any leakage is contaminating groundwater. Methane produced by anaerobic decomposition is collected and burnt to produce electricity or heat. Sanitary Landfills Site Selection:
- Should be above the water table, to minimize interaction with groundwater.
- Preferably located in clay or silt.
- Do not want to place in a rock quarry, as water can leech through the cracks inherent in rocks into a water fracture system.
- Do not want to locate in sand or gravel pits, as these have high leaching. Unfortunately, most of Long Island is sand or gravel, and many landfills are located in gravel pits after they were no longer being used.
- Do not want to locate in a flood plain. Most garbage tends to be less dense than water, so if the area of the landfill floods, the garbage will float to the top and wash away downstream.
A large number of adverse impacts may occur from landfill operations. These impacts can vary:
i. Fatal accidents (e.g., scavengers buried under waste piles).
ii. Infrastructure damage (e.g., damage to access roads by heavy vehicles).
iii. Pollution of the local environment (such as contamination of groundwater and/or aquifers by leakage and residual soil contamination during landfill usage, as well as after landfill closure).
iv. Off-gassing of methane generated by decaying organic wastes (methane is a greenhouse gas many times more potent than carbon dioxide, and can itself be a danger to inhabitants of an area).
v. Harbouring of disease vectors such as rats and flies, particularly from improperly operated landfills.
ii. Incineration:
The term incinerates means to burn something until nothing is left but ashes. An incinerator is a unit or facility used to burn trash and other types of waste until it is reduced to ash. An incinerator is constructed of heavy, well-insulated materials so that it does not give off extreme amounts of external heat.
The high levels of heat are kept inside the furnace or unit so that the waste is burned quickly and efficiently. If the heat were allowed to escape, the waste would not burn as completely or as rapidly. Incineration is a disposal method in which solid organic wastes are subjected to combustion to convert them into residue and gaseous products. This method is useful for the disposal of residue of both solid waste management and solid residue from wastewater management. This process reduces the volumes of solid waste to 20 to 30 percent of the original volume.
Incineration and other high-temperature waste treatment systems are sometimes described as “thermal treatment”. Incinerators convert waste materials into heat, gas, steam, and ash. Incineration is carried out both on a small scale by individuals and on a large scale by industry. It is used to dispose of solid, liquid, and gaseous waste. It is recognized as a practical method of disposing of certain hazardous waste materials. Incineration is a controversial method of waste disposal, due to issues such as the emission of gaseous pollutants.
iii. Composting:
Due to a shortage of space for a landfill in bigger cities, the biodegradable yard waste (kept separate from the municipal waste) is allowed to degrade or decompose in a medium. A good quality nutrient-rich and environmental-friendly manure are formed which improves the soil conditions and fertility.
Organic matter constitutes 35%-40% of the municipal solid waste generated in India. This waste can be recycled by the method of composting, one of the oldest forms of disposal. It is the natural process of decomposition of organic waste that yields manure or compost, which is very rich in nutrients.
Composting is a biological process in which micro-organisms, mainly fungi, and bacteria, convert degradable organic waste into humus like substance. This finished product, which looks like soil, is high in carbon and nitrogen and is an excellent medium for growing plants.
The process of composting ensures the waste that is produced in the kitchens is not carelessly thrown and left to rot. It recycles the nutrients and returns them to the soil as nutrients. Apart from being clean, cheap, and safe, composting can significantly reduce the amount of disposable garbage. Organic fertilizer can be used instead of chemical fertilizers and is better especially when used for vegetables. It increases the soil’s ability to hold water and makes the soil easier to cultivate. It helped the soil retain more of the plant nutrients.
Vermicomposting has become very popular in the last few years. In this method, worms are added to the compost. These help to break the waste and the added excreta of the worms makes the compost very rich in nutrients.
To make a compost pit, you have to select a cool, shaded corner of the garden or the school compound and dig a pit, which ideally should be 3 feet deep. This depth is convenient for aerobic composting as the compost has to be turned at regular intervals in this process.
Preferably the pit should be lined with granite or brick to prevent nitrate pollution of the subsoil water, which is known to be highly toxic. Each time the organic matter is added to the pit it should be covered with a layer of dried leaves or a thin layer of soil which allows air to enter the pit thereby preventing bad odor. At the end of 45 days, the rich pure organic matter is ready to be used.
Composting: some benefits
• Compost allows the soil to retain more plant nutrients over a longer period.
• It supplies part of the 16 essential elements needed by the plants.
• It helps reduce the adverse effects of excessive alkalinity, acidity, or the excessive use of chemical fertilizer.
• It makes soil easier to cultivate.
• It helps keep the soil cool in summer and warm in winter.
• It aids in preventing soil erosion by keeping the soil covered.
• It helps in controlling the growth of weeds in the garden.
iv. Pyrolysis:
A pyrolysis is a form of incineration that chemically decomposes organic materials by heat in the absence of oxygen. Pyrolysis typically occurs under pressure and at operating temperatures above 430 °C (800 °F).
In practice, it is not possible to achieve a completely oxygen-free atmosphere. Because some oxygen is present in any pyrolysis system, a small amount of oxidation occurs. If volatile or semi-volatile materials are present in the waste, thermal desorption will also occur.
Organic materials are transformed into gases, small quantities of liquid, and a solid residue containing carbon and ash. The off-gases may also be treated in a second thermal oxidation unit. Particulate removal equipment is also required. Several types of pyrolysis units are available, including the rotary kiln, rotary hearth furnace, and fluidized bed furnace. These units are similar to incinerators except that they operate at lower temperatures and with less air supply.
Limitations and Concerns:
i. The technology requires drying of the soil before treatment.
ii. Limited performance data are available for systems treating hazardous wastes containing polychlorinated biphenyls (PCBs), dioxins, and other organics. There is concern that systems that destroy chlorinated organic molecules by heat have the potential to create products of incomplete combustion, including dioxins and furans. These compounds are extremely toxic in the parts per trillion ranges. The MSO process reportedly does not produce dioxins and furans.
iii. The molten salt is usually recycled in the reactor chamber. However, depending on the waste treated (especially inorganics) and the amount of ash spent molten salt may be hazardous and require special care in the disposal.
iv. Pyrolysis is not effective in either destroying or physically separating organics from the contaminated medium. Volatile metals may be removed as a result of the higher temperatures associated with the process, but they are not destroyed. By-products containing heavy metals may require stabilization before final disposal.
v. When the off-gases are cooled, liquids condense, producing an oil/tar residue and contaminated water. These oils and tars may be hazardous wastes, requiring proper treatment, storage, and disposal.
The Environment Protection Act, 1986 The Environment Protection Act, 1986 was constituted on 19 Nov, 1986, to provide protection and improvement of environment and for matters connected with environment. The sprit of the proclamation adopted by the United Nations Conference on Human Environment, held in Stockholm in June 1972, was implemented by the Government of India by creating this act.
Air Pollution Acts
The Factories Act and Amendment, 1948 was the first to express concern for the working environment of the workers. The amendment of 1987 has sharpened its environmental focus and expanded its application to hazardous processes.
The Air (Prevention and Control of Pollution) Act, 1981 provides for the control and abatement of air pollution. It entrusts the power of enforcing this act to the Central Pollution Control Board (CPCB).
The Air (Prevention and Control of Pollution) Rules, 1982 defines the procedures of the meetings of the Boards and the powers entrusted to them.
The Atomic Energy Act, 1982 deals with radioactive waste.
The Air (Prevention and Control of Pollution) Amendment Act, 1987 empowers the central and state pollution control boards to meet with grave emergencies of air pollution.
The Motor Vehicles Act, 1988 states that all hazardous waste is to be properly packaged, labeled, and transported.
Acts Related to Water Pollution
The Indian Fisheries Act, 1897 establishes two sets of penal offences whereby the government can sue any person who uses dynamite or other explosive substance in any way (whether coastal or inland) with the intent to catch or destroy any fish, or poisonous fish in order to kill.
The River Boards Act, 1956 enables the states to enrol the central government in setting up an Advisory River Board to resolve issues in inter-state cooperation.
The Merchant Shipping Act, 1970 aims to deal with waste arising from ships along the coastal areas within a specified radius.
- Water Related Acts
The Water (Prevention and Control of Pollution) Act, 1974 establishes an institutional structure for preventing and abating water pollution. It establishes standards for water quality and effluent. Polluting industries must seek permission to discharge waste into effluent bodies. The CPCB (Central Pollution Control Board) was constituted under this Act.
The Water (Prevention and Control of Pollution) Cess Act, 1977 provides for the levy and collection of cess or fees on water consuming industries and local authorities.
The Water (Prevention and Control of Pollution) Cess Rules, 1978 contains the standard definitions and indicates the kind of and location of meters that every consumer of water is required to affix.
The Coastal Regulation Zone, 1991 Notification puts regulations on various activities, including construction. It gives some protection to the backwaters and estuaries.
Acts Related to Forests
The Indian Forest Act and Amendment, 1984 is one of the many surviving colonial statutes. It was enacted to ‘consolidate the law related to forest, the transit of forest produce, and the duty to be levied on timber and other forest produce’.
The Wildlife Protection Act and Rules, 1973 and Amendment 1991 provides for the protection of birds and animals and for all matters that are connected to it, whether it be their habitat or the waterhole or the forests that sustain them.
The Forest (Conservation) Act and Rules, 1981, provides for the protection of and the conservation of the forests.
The Biological Diversity Act, 2002 is an act to provide for the conservation of biological diversity, sustainable use of its components, and fair and equitable sharing of the benefits arising out of the use of biological resources and knowledge associated with it.
- Wildlife Protection Act
The Wildlife Protection Act , 1972 The Wildlife Protection Act of 1972 refers to a sweeping package of legislation enacted in 1972 by the Government of India. Before 1972, India only had five designated national parks. Among other reforms, the Act established schedules of protected plant and animal species; hunting or harvesting these species was largely outlawed. The Act provides for the protection of wild animals, birds and plants; and for matters connected therewith or ancillary or incidental thereto. It extends to the whole of India, except the State of Jammu and Kashmir which has its own wildlife act. It has six schedules which give varying degrees of protection. Schedule I and part II of Schedule II provide absolute protection - offences under these are prescribed the highest penalties. Species listed in Schedule III and Schedule IV are also protected, but the penalties are much lower. Schedule V includes the animals which may be hunted. The plants in Schedule VI are prohibited from cultivation and planting. The hunting to the Enforcement authorities have the power to compound offences under this Schedule (i.e. they impose fines on the offenders). Up to April 2010 there have been 16 convictions under this act relating to the death of tigers. Government of India enacted a comprehensive legislation Wildlife Protection Act of 1972 with the objective of effectively controlling poaching and illegal trade in wildlife and its derivatives. This has been amended (and signed) in January, 2003 and punishment and penalty for offences under the Act have been made more stringent.
Some of the important issues involved in enforcement of environmental legislation in India are as follows: 1. The precautionary principle, 2. The polluter-pays principle, 3. Freedom of information!
Once the legislation is made at the global, national or state level, it has to be implemented. For environmental legislation to be successfully implemented there has to be an effective agency to collect relevant data, process it and pass it on to a law enforcement agency. If the law or rule is broken by an individual or institution, this has to be punished through the legal process.
Three issues that are especially important for environmental legislation are:
1. The precautionary principle:
This principle has evolved to deal with risks and uncertainties faced by environmental management. The principle implies that an ounce of prevention is worth a pound of cure it does not prevent problems but may reduce their occurrence and helps ensure contingency plans are made.
The application of this principle requires either cautious progress until a development can be judged ‘innocent’, or avoiding development until research indicates exactly what the risks are, and then proceeding to minimize them.
Once a threat is identified, action should be taken to prevent or control damage even if there is uncertainly, about whether the threat is real. Some environmental problems become impossible or costly to solve if there is delay, therefore waiting for research and legal proof is not costless.
2. The polluter-pays principle:
In addition to, the obvious the polluter pays for the damaged caused by a development this principle also implies that a polluter pays for monitoring and policing. A problem with this approach is that fines may bankrupt small businesses, yet be low enough for a large company to write them off as an occasional overhead, which does little for pollution control.
There is, thus, debate as to whether the principle should be retrospective. Developing nations are seeking to have developed countries pay more for carbon dioxide and other emissions controls, arguing that they polluted the global environment during the Industrial Revolution, yet enjoy the fruits of invention from the era.
This principle, in fact, is more a way of allocating costs to the polluter than a legal principle. This principle was adopted by OECD member countries in 1972, at least in theory.
3. Freedom of information:
Environmental planning and management is hindered if the public, NGOs or even official bodies are unable to get information. Many countries have now begun to release more information, the USA has a Freedom of Information Act, and the European Union is moving in this direction.
But still many governors and multinational corporations fear that industrial secrets will lead to competitors if there is too much disclosure, and there are situations where authorities declare strategic needs and suspend disclosure.
Key takeaway
- Introduction of contaminants into the environment that makes the environment unhealthy for habitation and harms the ecosystem is known as pollution.
- Types of pollution include air, water, land, noise, thermal, radiation, solid-waste, etc. Solid waste management is necessary because daily life in industrialized nations can generate several pounds of solid waste per consumer.
- Types of waste are organic, toxic, recyclable, hospital.
- Acts that prevent and control Pollution are put forth for the protection of the environment and issues for enforcement of Environment legislature are also implemented to save the earth from environmental pollution.
References:
1. A.K. De, Environmental Chemistry, Wiley Eastern Ltd.
2. E.P. Odum, Fundamentals of Ecology, W.B. Sunders Co., USA.
3. M.N. Rao and A.K. Datta, Waste Water Treatment, Oxford and IBK Publications.
4. Benny Joseph, Environmental Studies, Tata McGraw Hill, 2005.
5. V.K. Sharma, Disaster Management, National Centre for Disaster Management, IIPE,1999.
