Download ENVIRONMENT - Environment pollution and more Lecture notes Environmental Science in PDF only on Docsity!
UNIT-IV
ENVIRONMENTAL POLLUTION, POLLUTION CONTROL TECHNOLOGIES AND
GLOBAL ENVIRONMENTAL PROBLEMS
Introduction : According to ODUM (1971), Pollution is ―an undesirable change in the characteristics of air, water and land that harmfully affect the life and also create health hazards for all living organisms on the globe‖. According to SOUTHWICK (1976), Pollution can be defined as ―the unfavorable (or) alteration of environment caused by human activities and causing harm to human beings‖. Basically the Pollution is of two types. (1) Natural Pollution : This type of pollution is limited in its occurrence generally from natural hazards like volcanic eruptions, emissions of natural gas, soil erosion, ultraviolet rays, cosmic rays etc and (2) Manmade Pollution : Most of the pollution is man made only. However, Pollution is usually categorized as Air Pollution; Water Pollution, Thermal Pollution; Noise Pollution; Land & soil Pollution; Radio Active Pollution and Marine Pollution. AIR POLLUTION Air pollution may be described as ―the imbalance in quality of air so as to cause adverse effects on the living organisms existing on earth‖. Pollution is due to the presence of undesirable substance of sufficient quantity which exists in environment. The substance or energy which causes pollution is called pollutant. Pollutants may be classified according to origin and state of matter. a) According to Origin: Air pollutants are divided into two categories as primary & secondary. Primary air pollutants are those which are emitted directly into the atmosphere. Eg: C, CO, CO 2 , SOx ,N, S,H, NOx, CFC‘s etc. Secondary air pollutants are those which are produced in the air by the interaction among the primary air pollutants or by reaction with atmospheric constituents. Eg: Ozone (O 3 ); Smog; Para Acetyl Nitrate (PAN); Acid Rain; Aerosols. b) According to State of Matter: Air pollutants include fine solids; liquids and gases. Dust, Smoke, Fumes etc are examples for solid particles whereas fog is an example for liquid particles. Benzene (C 6 H 6 ), Methane (CH 4 ), Butane, Aldehydes, Ketones, inorganic gases etc are gaseous air pollutants. Listed below are the major air pollutants : S.No Compound Pollutants 1 Carbon oxides Carbon Monoxide (CO); Carbon dioxide 2 Sulphur oxides Sulphur dioxide ( SO 2 ); Sulphur Trioxide ( SO 3 ) 3 Nitrogen oxides NO2; Nitrous oxide (N 2 O); Nitrogen Peroxide ( N 2 O 5 ) 4 Organic compounds Methane; Propane ( C 3 H 8 ) ; Benzene; Chloro Fluro Carbons ( CFC ) 5 Photochemical Oxidants Ozone ( O 3 ); PAN; Aldehydes 6 Radioactive substances Iodine 131; Strontium 90; Plutonium 239
Primary Pollutants: Carbon Monoxide: It is a colorless, odorless, poisonous gas that is produced by the incomplete burning of carbon based fuels (coal, petrol, diesel and wood) which comes from the automobile industries, exhaust devices, about 70% of CO emissions are from the transport sector. When the air is polluted with CO, human blood is likely to be deprived of oxygen and leads to coma and death. In mild dosages, it leads to headache. Oxides of Sulphur: SO 2 is a gas produced from burning of coal, mainly in thermal power plants. Some industries such as paper mills produce SO 2. It is injurious not only to men and plants, but it also attacks rapidly a few rocks such as limestones, marbles, electric contacts etc. It can even dissolve nylon. Paper absorbs SO 2 causing the paper to become brittle and fragile. SO 2 polluted air leads to corrosion of metals such as Fe, Zn, Cu, steel etc… SO 2 is a major contributor to Smog and acid rain. Sulphur trioxide is more irritant than SO 2 because it combines immediately with water to form sulphuric acid. Oxides of Nitrogen : Combustion of coal, oil, natural gas and gasoline which produces upto 50 ppm of Nitrogen. NOx are also produced when fossil fuels are burned especially in power plants and motor vehicles. NO 2 poisoning results SILOFILTER disease. High levels of NO 2 exposure causes cough and make the human beings feel short of breath. People who are exposed to NO 2 for a long time have a higher chance of getting respiratory infections. NOx compounds contribute for the formation of Ozone. Similarly, when nitrogen oxide when combine with SOx to form acid rain. Chloro Fluoro Carbons: CFC‘s (also known as Freon) are non- toxic. They contain Carbon, Fluorine and Chlorine atoms. The five main CFCs are the following: → CFC – 11 (Trichloro Fluoro Methane CFCl 3 ) → CFC – 12 (Dichloro Fluoro Methane CF 2 Cl 2 ) → CFC – 113 (Trichloro Trifluoro Ethane C 2 F 3 Cl 3 ) → CFC – 114 (Dichloro Tetrafluoro Ethane C 2 F 4 Cl 2 ) → CFC – 115 (Chloropenta Fluoro Ethane C 2 F 5 Cl) The major uses of CFCs are as coolants in refrigerators and in air conditioners; as solvents in cleaners particularly for electronic circuit boards etc. CFCs are the main cause of ozone depletion. CFCs have a lifetime in the atmosphere of about 20 to 100 years, and as a result one free chlorine atom from a CFC molecule can do a lot of damage. Secondary Pollutants: Ozone (O 3 ) / Ozone layer Depletion: Ozone consists of oxygen molecules which contain three oxygen atoms. It is not emitted directly into the air but produced in the atmosphere when oxygen combine with oxygen radical (O) in the presence of sunlight. Ozone protects us from ultra violet radiation and other harmful rays. It is observed that over the last few years, many man made processes release gases into atmosphere causing drastic depletion of ozone layer. The chlorine atoms cause depletion of ozone slowly and holes are formed in the ozone layer. Ozone reacts with tissues and cause for breathing and decrease the working ability of the lungs, chest pains and coughing. It lowers the human body resistance power and leads to cold; pneumonia also.
Ultra violet radiation from the sun is absorbed by ozone in the stratosphere which is so called ozone layer located between 17 - 26 kms above sea level. Effects of Air pollution: The effects of pollution may be direct and affect certain organisms. The effects of pollution may possess a hazard or nuisance. Long continued pollution even affects the evolution of a species and eliminates organisms that cannot tolerate certain pollutants and favour others who can eat. Air pollution causes deaths, Impair health, reduce visibility and brings vast economic losses. It can also cause intangible losses to historic monuments such as Taj Mahal. Finally, Air pollution can affect the environment o n a global scale. Prevention and control of Air Pollution: → Inputs that do not contain the pollutants. → Operating process to minimize generation of the pollutants. → Replacing the process with one does not generate the pollutant. → Removing the pollutants from the process. → Substitution of raw materials. Ex: The substitution of high sulphur coal with low sulphur coal in power plants. Ex: Changing a fossil fuel with nuclear energy can eliminate sulphur emission. → By involving the Process Modification: Ex: Chemical and petroleum industries have changed by implementing automated operations, computerized process control by reducing the oxidation of SO 2 to SO 3 by reducing excess air. → By involving the control technologies: Control equipment viz., Wet Collector (scrubber); Gravity Settling chamber; Cyclone Collectors; Dry Scrubbers; filters are to be used to minimize the air pollution. WATER POLLUTION Hydrosphere in the universe contains water in the form of oceans, rivers, lakes, tanks and many other water sources. Water sources in the world are of two types. They are (1) Marine water bodies and (2) Fresh Water bodies. Water is a good solvent for many substances. Because of this
property water cannot exist in its pure form at many parts of the world. Water pollution is mainly because of sewage, industrial disposals effluents. Chemical examination of water (tests): pH; Biological Oxygen Demand, Dissolved Oxygen; Chemical Oxygen Demand etc are some of the chemical tests to find the stage of pollution of water. pH : The value of pH gives the degree of acidity or alkalinity of polluted water. Determination of pH is important in calculating the coagulant (thick or thin) dose. Biological Oxygen Demand (BOD) : It is defined as the quantity of oxygen utilized by micro o organisms at a temperature of 20 C, generally measured for 5 days. When water is polluted by unwanted materials, naturally the O 2 content gets reduced and that water become not fit for consumption either by human beings or animals or plants. Living organisms require water with some quantity of sustainable oxygen in it. That oxygen is necessary for living organisms is generally called BOD. If there is reduction in oxygen content of water, it becomes unfit for biological consumption because there is change in BOD. Dissolved O 2 : The amount of oxygen in dissolved form in water at a particular temperature and atmospheric pressure is known as dissolved Oxygen. In polluted waters, dissolved oxygen is the factor which determines whether the biological changes are carried by aerobic (needing oxygen) or by anaerobic (oxygen not required) micro -organisms. Ex: 5 to 8 mg/L of dissolved oxygen is required for most of the species and fishes. Chemical Oxygen Demand (COD) : This test is conducted to determine the pollution strength of the sewage. Potassium dichromate and potassium permanganate are used as oxidizing agents. Common types of water pollutants: Disease causing agents: Bacteria, viruses, protozoan‘s that enter water from domestic sewage and animal wastes. Water soluble inorganic chemicals : Acids, salts and compounds of toxic metals such as Pb, Hg can make water unfit to drink, harm fishes and other aquatic life. Also Nitrate, Phosphate compounds dissolve in water that can cause excessive growth of algae, which then die and decay, depleting dissolved O 2 in water and killing fish. Water Soluble Organic chemicals: Oil, gasoline (a type of oil is obtained from petroleum), pesticides, detergents and many other water soluble chemicals that threaten human health and harm fish. Heat: Large quantity of water is heated when it is used in the cooling towers of thermal power plants. When this hot water is discharged into the nearby water bodies, it causes an increase in its temperature. Sewage: sewage is waste water from municipal area where there is human habitation. Sewage which comes from homes is called DOMESTIC SEWAGE : In nature water pollution is classified into three types by Kimball (1975). They are:
3. Industrial water pollution: Many industries discharge waste materials containing harmful chemicals. Such Industrial wastes are called effluents. Rivers get polluted when the river water is polluted by mixing of chemical substances released by the petrochemical industries, paper industries, chemical industries etc. The river Godavari is polluted because of effluents released by the paper industry. It affects the entire water ecosystem causing enormous damage to fishes, prawns and fresh water animals. Eg: Minimita disease & Fluorosis. Minamata disease is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech. In extreme cases, insanity, paralysis, coma, and death follow within weeks of the onset of symptoms. Minamata disease was first discovered in Minamata city in Japan in 1956. It was caused by the release of methyl mercury from, the Chisso Corporation's chemical factory, which continued from 1932 to 1968. This highly toxic chemical bio- accumulated in shellfish and fish in Minamata Bay which when eaten by the local populace resulted in mercury poisoning. While cat, dog, pig, and human deaths continued over more than 30 years, the government and company did little to prevent the pollution. Fluorosis: People suffer from a disease called fluorosis after consuming water containing fluorine for sufficiently a long time. Quantity of fluoride in water is only 1 ppm. Diseases caused by fluorosis are: → Back pain and cannot easily bend. → Joints get stiffened as so movement of joints is impaired. → Teeth are the worst effected and a brown coating appears on the enamel of teeth giving bad appearance. → Persons with fluorosis cannot erect freely. Preventions or control measures of water pollution:
- Drinking water should be boiled, cooled and then used.
- Disinfection of drinking water should be done by using chemicals like bleaching powder.
- Pesticides and insecticides should be prevented from nearby use of water lakes, ponds and pools.
- Drainage water should not be allowed to mix with drinking water. 5. Drainage system should be maintained properly.
- Chlorination process is to be adopted for drinking water. For 1 litre of water 30-40 mg of chlorine is to be added to get perfect disinfection. It kills bacteria, fungi, fungal spores and other microbes also. NOISE POLLUTION Everyone knows that sound is a form of energy that is capable of causing disturbances in human beings. Ears are the hearing organs in human beings. A thin membrane is called Tympanum (or) ear drum receives the vibrations produced by sound to a limited extent. Human ear is capable of perceiving about 85 decibels of sound. Beyond the limit, the ear drum cannot bear sound. In nature, we hear different types of sounds. Sound is a kind of vibration which travel through air, water, and are sensed by the ear. This is from music, speech, etc from radio / television /
computers etc., one thing in this matter is that we can increase the volume of sound or decrease as per our taste whereas, a noise is a sound which cannot be heard clearly and only mixed sounds will be heard. Ex: In an office one is talking on mobile, phone ringing another side, ring tones in some person's hands, loud conversations with one and another etc., this is called noise. One cannot increase or decrease the volume of noise. In general, a sound is a vibration from a particular machine, place or material which can be heard clearly whereas a noise a mixed vibrations that will come to us from all directions. A sound can be clear and can be able to hear, whereas a noise will not be clear and cannot be heard. Sources of Noise Noise is an unwanted sound and noise pollution occurs through different sources: → Vehicles produce noise that leads to noise pollution. → Automobile industry is another source of noise pollution. → Noise pollution is very common in industrial areas where machines are working for factories making more noise. The sources of noise are more in urban and industrial areas, than in rural areas. The sources of noise may be stationary or mobile. The stationary sources include industries, loud speakers, mining operations and use of machineries, TV, Radio and Grinders etc. The mobile sources include Road Traffic, Highway Noise, Railway Traffic and Air Traffic. (1) Stationary sources: Industrial noise: The main categories of industrial activity that are particularly relevant to the study of noise are the following: Product fabrication Product assembly Power generation by means of generators. Combusting process in furnaces. (Burning of gases) Noise from construction works: Construction noise, a major source of noise pollution is emitted by construction equipment. The sources of noise are dozers, excavators, front end loaders, soil compactors, cranes, air compressors, concrete vibrators, riveting steel structure during the casting, dismantling of construction materials etc... Noise from other sources: These include sources such as sirens, barking dogs, ambulances, Police vehicles, Fire engines etc. (3) Mobile sources: Road traffic : Of all sources of noise pollution, road traffic is the most prevalent and perhaps the most source of noise pollution. More people are exposed to noise from motor vehicles and the noise depends on various factors such as Road location, Road design, Vehicle standards, Driver behaviors, Horns, Traffic density. , Noise of common road vehicles Vehicle type Noise(db) Medium road traffic ( Main roads ) 70- 80 Heavy road traffic ( High ways ) 80- 90 Buses & Trucks upto 3.5 tons 85- 95 Trucks upto 3.5-12 tons 90- Motor cycles 90-
SOLID WASTE MANAGEMENT
Solid Waste is defined as ― any garbage, refused materials, sludge from a waste treatment plant and other discarded material including solids, semisolids etc resulting from industrial, commercial, mining, agricultural operations etc.‖ Solid Waste Management has become very important role in order to minimize the adverse effects of solid wastes. Solid waste ( other than liquid or gaseous ) can be classified as Municipal Solid Waste ( MSW ); Industrial Solid Waste; Hazardous Solid Waste; Agriculture Solid Waste; Mining Waste, Sewage Sludge Waste etc.. Solid wastes are being produced since the beginning of civilization. The disposal of Solid Waste has been increased due to the rapid developments in industrialization and urbanization. High population density, intensive land use for residential, commercial and industrial activities led to generation of more solid waste. In Andhra Pradesh, the solid waste generated in medium and small municipalities in the range of 30 – 150 MT / day. The per capita generation of Municipal solid waste in class I cities is in between 100 – 500 gms / day per person. Sources of Solid Wastes:
- Municipal Solid Waste is commonly known as garbage consists of packing materials, furniture, clothing, bottles, food scraps, newspapers, home appliances; paints, batteries etc. Municipal solid wastes are arise from residential quarters, commercial (markets, hotels, garages); institutions; public places, open areas/streets, parks, play grounds etc. MSW also include the follo wing wastes: Food Wastes usually generate from domestic houses, hotels, markets and consist of fruits, vegetable residues resulting from the handling, preparation, cooking and eating of foods. Rubbish waste consists of combustible wastes (papers; cardboards, torn clothes, plastics, wood etc) and non – combustible waste (glass, crockery, aluminum tins, ferrous metals; construction wastes). Demolition & Construction wastes result from the construction, remodeling and repairing of residential, commercial buildings and industrial factories. These wastes include dust, stones, concrete, bricks, steel pieces etc. Special Wastes include street sweepings, road side litter, drainage debris; dead animals and abandoned vehicle parts.
- Industrial Waste arise from industrial activities such as chemical industries; metal and mineral processing industries. Radio Active wastes are generated by Nuclear Power Plants. Thermal Power Plants produce fly ash in large quantities. Fly ash is a fine solid particles result from the burning of wood, coal and other combustible wastes.
- Hazardous Solid Waste is any solid waste or combination of wastes that posses a substantial danger, now or in future to human beings and plant / animal life and cannot be handled or disposed. The following is a list of types of hazardous wastes: → wastes from specific and non-specific sources. Ex: Disposable synergies from hospitals is a specif ic source identified as hazardous solid waste. → Ignitable materials (easily inflammable below o 60 C) → Corrosive materials (iron rods / pieces)
→Reactive materials (undergoes rapid reaction with water or other substances and releases toxic gases. Ex: limestone / marble). → Toxic materials which consists of Pb, Cl (Toxic to human beings) Effects of Solid Waste: The improper handling and transfer of the solid wastes results in various health and environmental problems. The main impacts of waste accumulation are: → Garbage dumping places are breeding places for diseases. → Rats and pigs roam and feed on garbage and transmit diseases like brain fever from pigs to human beings and plagu e from Rats. → Solid wastes may choke the drains and gully pits resulting in water logging which in turn results in breeding of mosquitoes and then cause for Malaria & dengue in human beings. → Noxious fumes (harmful gas) may pollute air due to the burning of waste products especially plastic containers. → Obnoxious (very unpleasant) odours pollute the air due to decomposition of organic solid wastes. → Municipal solid wastes heap up on roads due to improper disposal system. Every year several tones of solid waste is dumped along the high-ways thereby spoiling the landscape (appearance of an area of land). → Urban and industrial solid wastes often contain a variety of toxic chemicals which may enter into the food chain and affect both terrestrial and aquatic organisms. GLOBAL ENVIRONMENTAL PROBLEMS & GOBAL EFFORTS The problems caused by pollutants such as NOx, Sox etc are now worldwide issues. Heating of earth surface; poor air quality in urban areas; the formation of acid rains, depletion of ozone layer; emission of gases are of our environmental issues which are to be studied. Climate Change & their impacts on Human Environment: The weather conditions and seasonal variations in a region over a long period are called the average temperature in many regions has-been increasing in recent decades. Globally, 1990 was the warmest decade on record. Climatologists of the Inter-governmental Panel on Climate changes (IPCC) have carried out several experiments in order to estimate the changes in climate. Accordingly, First Assessment Report (FAR) was completed in 1990 and Second Assessment Report (SAR) in 1997. Following are the main points from the climate reports: → The concentration of Green House Gases in the atmosphere such as CO 2 ; Methane; Nitrous Oxide have all increased markedly since 1750 and now exceed ed the levels. → Emission of Carbon dioxide from fossil fuel has been increased from 1990‘s onwards. The Third Assessment Report (TAR) on climate change 2001 is the most comprehensive and up- todate scientific assessment of past, present and future climate change. The report: → Analyses an enormous body of observations of all parts of the climate system. → Increasing concentrations of atmospheric greenhouse gases. → Assesses our understanding of the processes and feedbacks which govern the climate system. → Projects related to scenarios of future climate change using a wide range of models of future emissions of greenhouse gases and aerosols. Fourth Assessment Report was released in 2007 and concluded that 90% of human beings are caused for Global Warming.
O 2 + UV → O + O
O + O 2 → O 3
Destroy of Ozone Layer: Two different processes destroy ozone naturally: The first is when a free oxygen radical combines with an ozone molecule to produce two diatomic oxygen molecules. O + O 3 → 2O The other process when ozone molecules absorb ultraviolet radiation and form one diatomic oxygen molecule and one free oxygen radical. O 3 + UV → O + O 2 Ozone Depleting Substances (ODS) Ozone Depleting Substances (ODS) are those which deplete the ozone layer. The ODS‘s Chloro Fluo ro Carbons (CFS‘s) Hydro Chloro Fluoro Carbons (HCFS‘s) Methyl Chloroform Carbon Tetrachloride and Halogens (MCCTH‘s) Effects on human beings : → Ozone makes human beings eyes itch, burning sensation. → It lowers the human body resistance power and leads to cold and pneumonia. → Ozone reacts with tissues and cause for breathing and decrease the working ability of the lungs → The thinning of the ozone layer may lead to an increase of skin cancers. Effects on Global environment : Certain crops may be damaged if ozone layer is depleted thus affecting natural food chains and food webs so that the ecology system disturbs. The effect of ozone depletion in Antarctica is severe; however, the ozone in the arctic region should not be neglected. Depletion of ozone causes Global warming. International Conventions / Protocols: Convention: large formal meeting of people with the same interest or work. Protocol: The rules about what you must do and how you behave in an official situation. The objectives of the International Conventions are to stabilize the Green House Gas concentrations in the atmosphere to certain levels to prevent dangerous human interference with the climate system of the world.. Earth Summit : The United Nations Conference on Environment and Development (UNCED), also known as the Rio Summit , Rio Conference , Earth Summit (Portuguese) was a major conference held in Rio de Janeiro from 3 June to 14 June 1992. Totally 172 Governments were participated with their heads and representatives, NGO‘s accounting 17000 people. The issues included: → Systematic scrutiny of patterns of production of Toxic components such as lead in gasoline. → Alternative sources of energy to replace the use of fossil fuels which are linked to global climatic changes. → By introducing new public transport system in order to reduce vehicle emissions in cities. → Alarming the growing scarcity of water and has been decided to come out with proper utilization methodologies.
→ Not to carry out any activities on lands that would cause environment degradation. Montreal Protocol : Several meetings have taken place to address the ozone layer depletion problem. The well known meeting was held in Montreal on 16-09-1987 and the agreement signed is called the Montreal Protocol, which set a timetable to phase out of CFCs as well as halogens which contain bromine and 96 harmful chemicals in the Protocol subject the schedules. The Montreal Protocol on substances that deplete the Ozone Layer is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances believed to be responsible for ozone depletion. The treaty was opened for signature on September 16, 1987, and entered into force on January 1, 1989, followed by a first meeting in Helsinki (Finland), May 1989. Since then, it has undergone seven revisions, in 1990 (London), 1991 (Nairobi capital of Kenya), 1992 (Copenhagen, capital of Denmark), 1993 (Bangkok in Thailand, SE Asia), 1995 (Vienna, capital of Austria), 1997 (Montreal, Canada), and 1999 (Beijing, china). After implementing the sche dules, following are the identified advantages: Montreal protocol : → The highest calculated level of consumption of CFCs was 16,255 metric tons in 1988. Substances were used chiefly as refrigerants, cleaning solvent, foam blowing agents and propellants in spray can. In 1996 the consumption level was reduced to zero and maintain at that level since. → HCFCs have been used as one of the alternative substances for CFCs since 1996. As a result, consumption of HCFCs was reduced from around 630 ODP (Ozone Depletion Potential) metric tons in 1996 to 383 ODP metric tons in 2004, which indicated a 40% reduction from the baseline level. → Without the protocol there would be a doubling effect of Ultra violet – Beta radiations reached the earth in the northern latitudes and also the amount of ozone depleting chemicals in the atmosphere would have been 5 times greater.
The removal of trees leads to soil exposure & results in soil erosion, rapid water run-off, loss of wildlife. Deforestation ---- cause unknown effects on global climate and eliminating the majority of plant and animal species on this earth. Various living beings (wildlife is diminishing) may come down resulting in imbalance of forest ecosystem. → A variety of food products such as coffee, tea, spices, nuts, fruits etc will be reduced. → Rainfall decreases to a great extent. → Climatic conditions may are change. → Historical values are lost. Case Studies : Chipko movement related to mining or quarrying opposed by Sundarlal Bahuguna in North India (refer text books for further information) Sardar Sarovar – Narmada project is a multipurpose project in Gujarat (refer text books for further information) Desertification : The processes by which an area becomes even more barren, less capable of retaining vegetation and is known as a desert. This may become a disaster in long term. Hence, desertification refers to land degradation in arid and semi-arid areas due to anthropogenic activities. Desertification often starts as patchy destruction of productive land. Increased dust particles in atmosphere also lead to desertification. The chief causes of desertification also include: Climatic factors and (ii) human factors (population growth, increased population density According to the United Nations Environmental Programme (UNEP), deforestation is an important factor contributing to desertification. At the time of Independence in India, about 22% of area was under forest cover and today this has been reduced to 19% UNEP estimated that desertification threatened 35% of the world‘s land surface and
UNIT – V
ENVIRONMENTAL LEGISLATIONS AND SUSTAINABLE DEVELOPMENT
National Environmental Policy: The Govt of India constituted a Central Board for Prevention and Control of various pollution acts such as Water Act in 1974; Air Act in 1981andEnvironment Act in 1986.Several other Acts and Rules were also enacted Accordingly all the State Governments also constituted Pollution Control Boards in their respective States and accepted in their legislative Assemblies There are several loopholes in the implementation of various pollution Acts For eg the water courses in most of the cities carry highly noxious waters with high pollution potential. State Pollution Control Boards cannot take action against the Municipalities, Corporations, simply because they are not empowered to do so due to political system. The Environment (Protection) Act, 1986: Bhopal tragedy was occurred on the mid night of 2nd Dec 1984 at the UNION CARBIDE INDIA LTD, a pesticide plant in Bhopal. A leak of methyl isocyanate gas causing a death of 3,787 people and also injuredfor5, 58,125 people. The Govt of India enacted the Environment (Protection) Act in the year1986 under article 253 of the constitution. The purpose of the Act to provide a frame work on water, air, land and the inter-relationships with the human beings and other living micro-organisms… The Act came into force on Nov, 19th 1986, the birth anniversary of late Prime Minister Indira Gandhi, who was a pioneer of environmental protection issues in India. Some important features of this Act are:
- The central Government put restrictions on an area in which any industry or operations shall not be carried out without any safe-guards. Emissions and effluents standards in respect of 61 categories of Industries have been evolved and notified.
Forest (conservation) Act 1980 Forest is a biotic community composed predominantly of trees, shrubs, bushes etc. whereas forest produce includes timber, charcoal, oils, resins, tree bark, seeds, fruits , flowers, grass, honey, wax etc. Increasing Population is causing for decrease in biotic community ie forests and implementation of forest conservation is essential and mandatory. Forest (Conservation) Act was enacted in the parliament in 1980. The State Governments or other agencies (eg ITDA) cannot violate the Forest (Conservation) Act unless prior approval by the Central Government. The objectives of the Forest (Conservation) Act are: Restrictions on preservation of forests and use of forest land for Other purposes.
- Forest land or any portion thereof may not be used for non- forest Purposes.
- Forest land may not be assigned by way of lease to a private Person or to any corporation / agency.
- Forest land may not be cleared off trees which have grown naturally in that land. However, according to Section 32 of Forest (Conservation Act, the State Governments can make avail the use of :Removal of forest produces, conversion timber etc for proper utilization Granting of license to the agencies / inhabitants to collect timber and forest produce for their own use. Granting of license to persons for felled trees / timber and other forest produces for trade purposes. The Forest (Conservation) Act also include: Prohibition of hunting, shooting, fishing, poisoning of water in forest areas.
- No clearance of forest land for cultivation or other purposes Protection of timber from fire. The wildlife (protection) act, 1972 An Act to provide for the protection of [Wild animals, birds and plants]^1 and for matters connected therewith or ancillary or incidental thereto This Act may be called the Wildlife (Protection) Act, 1972 It extends to the whole of India, except the State of Jammu and Kashmir. It shall come into force in a State or Union Territory to which it extends, on such date as the Central Government may, by notification, appoint, and different dates may be appointed for different provision of this Act or for different States or Union Territories "Animal" includes amphibians, birds, mammals, and reptiles, and their young, and also includes, in the cases of birds and reptiles, their eggs, The Act has been made applicable in various States and Union Territories as under:
- Andaman and Nicobar, w.e.f. Ist July 1973, vide G.S.R.332 (E), dated Ist July, 1973. 2. Andhra Pradesh, w.e.f. Ist July 1973, vide G.S.R.371 (E), dated Ist August, 1973 3. Arunachal Pradesh, w.e.f. 15th May 1973. 4. Assam, w.e.f. 25th January 1977, vide G.S.R.33 (E), dated 25th January, 1977. 5. Bihar, w.e.f. Ist February 1973, vide G.S.R.40 (E), dated Ist February, 1973. Municipal Solid Waste (Management and Handling) rules 2000: Central Government notified in the sections of 3, 6 and 25 of the Environment (Protection) Act 1986 with the objective of regulating them anagement and handling of the Municipal Solid Wastes. Municipal solid waste generate in residential and commercial areas. Residential wastes
include garbage, unused house hold items, pieces of clothes, rotten vegetables etc while commercial establishments generate different wastes depending upon the type of activity. For eg: shops and other establishments generate wastes containing large quantity of paper, and cardboard packing cases .The wastes from streets are also part of the municipal solid wastes. Street wastes are classified into 3 main categories – natural waste, road traffic waste and behavioral waste. Natural wastes include the dust blown from unused lands / roads. Road traffic waste originates from transport vehicles. The motor vehicle while moving on the road deposit petrol, oil at sometimes and still their contents (grease, lubricants) on roads. Behavioral wastes originate from wastes thrown by pedestrians using the streets and the wastes from adjoining houses, shops which spill out due to improper storage. Municipal Solid Waste Management: It is estimated that 291 class I and 345 Class II towns together generate52000 tons of Municipal Solid Waste per day in India. Solid wastes are generated @ 10,000 tons /day in all the 117 municipalities / corporations of Andhra Pradesh. To minimize the municipal solid waste, the Municipal authority made an implementation of Management plan as per Schedule – I. Any municipal solid waste generated in a city or a town, shall be managed and handled in accordance with the procedure laid down in Schedule - II. The waste processing units and disposal facilities are to be set up by them municipal authority on their own or through an operator shall meet the specifications and standards as specified in schedule – III. Treatment of solid wastes: Basically there are 3 types of disposal techniques practiced in Municipal solid wastes. (i) Sanitary Land Fill (ii) Composting (iii) Incineration. (i) Dumping the solid waste at the out-skirts of the city, especially in low lying areas, or on either Side of the road is very common. In case of mineral excavations, granite quarries or soil excavation for brick making, low lying areas are created. Restoration to original level with solid wastes is a good example for sanitary landfill. (ii) Decomposition of solid waste material is known as Composting and the final product is called compost. Compost contains nutrients (NPK) for the growth of plants. A few methods of treatment and disposal of composting system are given below: The composting systems can be broadly grouped as aerobic and anerobic. Composting systems can be operated either manually or mechanically in open pits or in enclosed digesters in addition to natural process. Aerobic composting is a process in which bacteria, actinomycites, fungi and other biological forms are actively involve. Aeration is a natural process occurs on the surface areas of the composting mass, while the in near layers tend to progressively turn anaerobic. Trench method is best suited for flat land where excavation can be carried out easily. A trench 2 mts deep with 5 mts length and 2 mts wide is cut. The excavated soil is placed on the sides of the trench and the trench is filled with solid waste refuse in layers and finally with a soil cover .Area method is best used in areas where natural depressions exist as in quarries, valleys. The waste is put in the natural depressions and compacted a layer of soil is thrown on top. The process is repeated till the depression is filled up. (iii) Incineration is a common sight to see small fires of burning dry
