Q. No. 2. (a) What were the main objectives of Clean Development Mechanism? Mechanism? Also explain the reasons for the criticism on Koyoto Protocol by the developed countries.
The ‘Reduce, Reuse, Recycle’ Waste Hierarchy If you have heard o f something called the “waste hierarchy” you may be wondering what that means. It is the order of priority of actions to be taken to reduce the amount of waste generated, and to improve overall waste management processes and programs. The waste hierarchy consists of 3 R’s as follows: Reduce Reuse Recycle Called the “three R’s” of waste management, this waste hierarchy is the guidance suggested for creating a sustainable life. You might be wondering as to how can you incorporate these principles in your daily life. They are not hard to implement. All you need is to bring a small change in your daily lifestyle to reduce waste so that less amount of it go es to the landfill that can reduce your carbon footprint. “The three R’s – reduce, reuse and recycle – all help to cut down o n the amount of waste we throw away. They conserve natural resources, landfill space and energy. Plus, the three R’s save land and money communities must use to dispose of waste in landfills. Siting a new landfill has become difficult and more expensive due to environmental regulations and public opposition.” By refusing to buy items that you d on’t need, reusing items more than once and disposing the items that are no longer in use at appropriate recycling centers, you can contribute towards a healthier planet.
The First ‘R’ – Reduce The concept of reducing what is produced and what is consumed is essential to the waste hierarchy. The logic b ehind it is simple to understand – if there is less waste, then there is less to recycle or reuse. The process of reducing begins with an examination of what you are using, and what it is used for. There are three simple steps to assessing the reduction value of an item or process –
Is there something else that can be used for this purpose? Using multi-use items is essential to beginning reduction. One example would be a coffeepot and a cappuccino maker. Both of them do distinctly different things, but you can buy a coffeepot that has a steaming attachment on it so it can do both. The purchase of the one item means that you don’t use two. It reduces the amount of production, and the amount of waste packaging material that will be generated.
Is this something that needs to be do ne? A lot of our waste material comes from items that are considered to be “disposable.” Not in the sense that you use something once and t hen throw it away, that can actually be a part of environmental responsibility when you are working with medical items – disposable in this sense means whether or no t what the item allows you to do has any real meaning or purpose.
Is the item a part of something that you need to do, or want to do in your life? There is a limit to what you need to be prepared for in life. Chances are you won’t need a car th at is equipped to handle a sandstorm in the d esert. Buying one encourages production, wastes your resources and creates more generative waste than you can imagine. Always make sure that what you consume, or keep in your life as preparation – matches the reality of potential opportunity in your life. Here are some of things you can do to reduce the waste: 1. Print on both sides of the paper to reduce paper wastage. 2. Use electronic mail to reach out to people instead of sending paper mail. 3. Remove your name from the mailing lists that you no longer want to receive. 4. Use cloth napkins instead of paper napkins. 5. Avoid using disposable plates, spoons, glass, cups and napkins. They add to the problem and result in large amount of waste. 6. Avoid buying items that are over-packaged with foil, p aper, and plastic. This excess packaging goes to waste. 7. Buy durable goods that have long warranty. They generally run longer and save landfill space. Number 3 deals with the problems created by living within a culture of consumerism. This type of consumption driven culture also makes fulfilling the second “R” difficult, but it is getting easier to do.
The Second ‘R’ – Reuse You may have a box of things you keep that are broken or that you don’t have a use for that you hang on to in-case you find another use for them; or you may find bargains on old furniture or go trash picking and get things that you can refinish – in either case you are working towards reusing the item. Learning to reuse items, or re-purpose them for a u se different then what they are intended for is essential in waste hierarchy. One of the best examples for how this is being done today is th e modular construction of homes and office buildings that is being created out of discarded shipping containers. These large, semi-truck sized metal containers represent a huge waste prob lem. Repurposing them as homes and offices saves them from the landfills and doesn’t require the additional expenditure of nature resources to melt down and reconfigure the metals used to create them. You may either reuse those items for your own use or donate so that others can use them. You can reuse below items like: 1. Old jars and pots: Old jars and pots can be used to store items in kitchen. They can also b e used to store loose items together such as computer wires.
2. Tyres: Old tyres can either be sent to recycling station or can be used to make tyre-swing. 3. Used wood: Used wood can be used as firewood or can be used woodcrafts. 4. Newspaper: Old newspapers can be used to pack items when you’re planning to move to another ho me or store old items. 5. Envelopes: Old and waste envelopes can b e used by children to make short n otes. 6. Waste paper: Waste paper can be used to make notes and sketches and can be send to recycling center when you don ’t need them anymore. Items that can be donated to others include: 1. Old books: Your old books can be used by poor children or can be donated to public libraries. 2. Old clothes: Your un wanted clothes can be used by street children or can be donated to charity institutions. 3. Old electric equipment: Old electric equipment can be donated to schools or NGO’s so that they can use them. 4. Rechargeable batteries: Rechargeable batteries can be used again and again and helps to reduce unnecessary wastage as opposed to regular batteries. Apart from this, you can build a compost bin and reuse many waste items like used tea bags. The waste then degrades and turns into compost that help your plants grow and shine.
The Third ‘R’ – Recycling The last stage of the waste hierarchy is to recycle. To recycle something means that it will be transformed again into a raw material that can be shaped into a new item. There are very few materials on the earth that cannot be recycled. One of the issues facing communities that want to become more involved with a recycling effort is that while the relying collection and sorting process may be affordable to implement, there still has to be a facility to receive and transform the discarded waste into a raw material. More progress is being made toward uniting recycling plants with industries that can process the waste material through agreements and incentive credits. One need to learn as to what p roducts can be recycled and what not. By carefully choosing the products that can b e recycled, can be a first step towards efficient recycling. 1. Buy products from market that are made up of recycled materials i.e. the product should be environment friendly. 2. Buy products that can be recycled such as glass jars. 3. Invent new ways to recycle different items. 4. Avoid buying hazardous materials that could pose difficulty for you to recycle. Buy non-toxic products, whenever possible. 5. Buy products that have been made from recycled material. 6. Use recycled paper for printing or making paper handicrafts.
(b) Differentiate between Sanitary and Industrial Landfills, also describe the land selection criteria for Landfills.
Types of Landfills Sanitary landfills - landfill that uses a clay liner to isolate the trash from the e nvironment SANITARY LANDFILLS Sights where waste is isolated from t he environment until it is safe. It is considered safe when it has completely degraded biologically, chemically, and physically. Sanitary landfills use technology to contain the waste and prevent the leaching out of potentially hazardous substances. There are two main methods used in sanitary landfills, the trench method and the area method.
–Municipal solid waste (MSW) landfills - uses a synthetic (plastic) liner to isolate the trash from the environment This type of landfill collects household garbage and are regulated by state and local governments. The Environmental Protection Agency (EPA) has established minimum criteria that these landfills must meet. Some materials may be banned from disposal in municipal solid waste landfills. Items such as paints, cleaners, chemicals, motor oil, batteries, and pesticides are some of the common items that are banned from MSW's. However, some household appliances can be turned into MSW's for disposal.
–Construction and demolition waste landfills - consist of the debris generated during the construction, renovation, and demolition of buildings, roads, and bridges. These types of landfills used for debris generated during co nstruction, renovations, demolitions of buildings and bridges. The types of debris include: concrete, wood, asphalt, gypsum (the main component of drywall), metals, bricks, glass, plastics, trees, stumps, eart h, rock, and building components (doors, windows, plumbing fixtures).
–Industrial Waste Landfills- nonhazardous solid waste, consists of nonhazardous waste associated with manufacturing and other industrial activities Industrial hazardous waste is a separate form of waste consisting of nonhazardous waste associated with manufacturing and other industrial activities.
Criteria for Selection of Land fill Site Landfill site for solid wastes should be selected on following criteria:
Land area and volume should be sufficient enough to provide landfill capacity so that the projected need can be fulfilled for several years. In this way the cost coming on all that procedure can be justified. The landfill site should not be at locations where suitable buffer zones between land fill sit e and population are not available. The landfill area having steep gradient (where stability of slope could be problematic) should not be selected. The water level in ground water table should be sufficient below the base of any excavation to enable landfill development. The land which is significant environmentally (lands of biodiversity); the sensitive ecological area of such a land should be present within potential area of landfill site. Public & private irrigation water supply wells should be well away from the boundaries of landfill site because these supply wells will be at risk of contamination. Landfill area should not be very close to significant water bodies (water courses or dams). There will be the risk of contamination of water bodies, which can be hazardous for aquatic life. No major power transmission or other infrastructure like sewers, water supply lines should be crossing through landfill developmental area. No residential development should be near the boundaries of landfill site. The waste disposal site must be very away from residential or commercial areas and water resources. Landscaping and protective shelf should be included in the design so that to minimize the visibility of operations. Unstable areas that have significant seismic risk which could cause destruction of berms are not recommended for landfill site. There should not be fault lines and significantly fractured geological structure. These fault lines can allow the unpredictable movement of gas within 500 meters of perimeter of proposed landfill development. Groundwater quality should not be disturbed during the site developmental phase. There should be monitoring facilities at site in order to ensure that ground water quality is maintained. In areas under the laws of concerned municipality it should be responsibility of municipality to identify landfill site and handover to operators for operations. Selection of landfill site should be based upon the examination of environmental issues. The landfill site should be near the wastes recycling facility otherwise, the waste recycling facility should be planned as integral part of landfill site. Biomedical wastes should be disposed off in accordance with guidelines issued by Ministry Of Health, Government of Pakistan.
Landfill site should be away from airports. There is need of approval of airbase authorities like civil aviation authorities of government of Pakistan for setting up of landfill site in case if site is to be locating within ten kilometer of an airport boundary.
Q. No. 3. (a) Write a short note on artificial intelligence.
(b) Write short notes on: (2½ each) (i) Fibre Optics (ii) Global Positioning System
Q. No. 4. (a) What are vaccines? Classify these and discuss DNA vaccines in detail. (b) What are causative organism and vector for dengue, enlist possible ways of prevention from dengue.
Q. No. 5. (a) Comment, ‘liver is the chief chemist in human body’. (b) What is Cholesterol? Discuss its importance, normal blood level and dangers of elevated levels with reference to the health and disease in humans.
Q. No. 6. (a) What do you know about the Remote Sensing Techniques? Explain resolution and write down the names of its various types? (b) What is hydrological cycle? Discuss its importance.
Q. No. 7. (a) What is tsunami? How the tsunamis generated and what are their characteristics? (b) What is an earth quake? Discuss Richter Scale in this context. What was the intensity of the earth quake in Pakistan dated 26 October 2015 and where was the locus?
Q. No. 8. (a) Explain the shape of water molecule with the help of Molecular Orbital Theory, also draw its orbital diagram. (b) What are the gamma rays? Explain their applications.
Q. No. 9. (a) Discuss importance of preservatives and antioxidants in food. (b) Comment, Green House Effect is a blessing. Also discuss Enhanced Green House Effect and its relation with global warming.
