Sunday, October 27, 2019
An Environmental Risk Assessment Environmental Sciences Essay
An Environmental Risk Assessment Environmental Sciences Essay All over the world, rapid industrial development of metropolitan cities have always resulted in a growth in population and also in the general increase of the size of municipal solid waste generated. The management of municipal solid waste, if not handled properly, will lead to various problems now and in the future. Developed countries in the world have, to a large extent succeeded in handling their waste using various principles and methods. From suitable collection methods to technologically advanced disposal methods, they have made sure that municipal solid waste has been effectively controlled in their cities. Unfortunately, the same cannot be said about other developing countries of the world. Developing countries such as Nigeria are still battling with municipal solid waste management. As a direct result of the oil boom, Port Harcourt city, the capital of Rivers State, Nigeria (which is the case study of this research work) has experienced a major rural- urban migration. The population has almost tripled over the years. This has, in turn, led to a massive increase in the sheer volume of solid waste generated within the city.. Approximately 168,201 tonnes of solid waste are produced in the city of Port Harcourt every year and waste disposal has not been effectively handled. Residents resort to indiscriminate discarding of their waste at every given opportunity The most common means of waste disposal in the city by the public are mainly by dumping the refuse by the road, burning the refuse in the open air in their compounds, littering it openly on street corners and also dumping them in rivers and streams and drainage systems. These methods of waste disposal contribute greatly to the degradation of the environment in so many ways. However, very little is done to reuse and recycle the solid waste generated. Research shows that a huge percentage of the public do not recycle and reuse their wastes which indicates that the awareness level of the public about reuse and recycling of waste in Port Harcourt city is very low and offers a lot of prospect for improvement. This study therefore investigates the reasons why proper waste disposal methods are neglected by residents of Port Harcourt. It also seeks to discover why the method of Reuse and Recycle of waste is not getting the awareness and Government support it greatly deserves. Recommendations were made about strategies that will allow the government and stakeholders involved to advance on modern methods of waste Reuse and Recycling as a core aspect of municipal solid waste management in the city. Through the use of data collated via questionnaires, it was gathered that a majority of respondents agree that reuse and recycling of waste can positively impact the environment, create revenue and also employment opportunities. It reconnoitres the link between reuse and recycling of solid waste as a means to create revenue and to ultimately achieve sustainable development in the future. CHAPTER ONE INTRODUCTION BACKGROUND OF STUDY According to Shah (2000), solid waste is defined as any material that is unwanted or thrown away. The general community views waste as something worthless that should be destroyed or thrown away. As such, proper disposal of waste has constituted huge disposal problems. People commonly dump their household solid waste on the road side, unapproved dumpsites and illegal landfills. This has brought about untold environmental pollution as well as major setbacks in societal development (Mbata 2010). Waste in general is a threat to the environment, because of its negative environmental impacts that result from littering, dumping of wastes illegally, and greenhouse gas emissions (Hosetti 2006). Waste contaminates ground water and can cause serious health hazards if not handled and managed properly. In developing countries like Nigeria and indeed Africa in general, industrial development has enhanced the problems of rapid urbanization. In Nigeria today, solid waste management is one of the principal problems faced by the state and local government authorities in Nigeria. Solid waste management in Nigeria is basically pigeon-holed by ineffective collection and disposal methods (Ogwueleka 2009). As such, Ogu (2000) observed that solid waste management continues to remain a formidable challenge to most developing countries. The progression of civilization in developing nations such as Nigeria has greatly enhanced waste generation; making it even more complex to handle (Jayarama, 2011). Owing to the growing population of Nigeria, the volume of waste produced is also increasing in metropolitan cities like Port Harcourt, especially as it is an oil producing area and the exploration of oil has led to an increase in movement of people from rural to urban areas (Odiba, 2009). This rapid expansion of key cities in Nigeria, like Port Harcourt, has led to the dilapidation of the environment mostly by domestic waste (Onyinlola, 2005). According to UNEP (2009) population growth and industrialization has resulted in rapid increase in the types and volume of solid waste generated therein. Research shows that relocation of the people from rural to urban areas does not only increase the revenue of the country, but also increases the total volume of municipal solid waste generated in such areas. (Adedokun, 2009). Municipal solid waste disposal methods are an aspect that raises serious concern in a third world country such as Nigeria. The common methods of solid waste disposal in some countries especially Nigeria is by landfill, open dumping on the streets, and by burning the waste in backyards or in an open space. Unfortunately, roughly 65% of household wastes are dumped straight into rivers or streams in Nigeria (Rakshit 2009). The use of dumpsites and landfills as waste disposal systems is yet another common means of waste disposal in Port Harcourt, Nigeria. This leads to very negative environmental impacts such as the emission of methane gas which contributes essentially to global warming and also reduces the amount of land available for development (Olowomeye 2010). Dumping of waste in landfills also leads to ground water contamination of the entire surrounding areas. Okosun(2011) also observed that uncontrolled dumping of wastes by roadsides results in various health hazards and reduces the aesthetic quality of the environment. Through research shows that the problems associated with waste disposal can be traced back to the 14th century when the littering of food waste and other solid wastes in the town led to the outbreak of diseases that caused the death of half of the Europeans at the time (Bortoleto 2011). Over the years, research has continually shown that the main reason for solid waste problems in urban areas of developing nations is due to high population growth rates and the prevailing poverty (Affun 2009). The economic and social growth of a country or city always results in increased production and manufacturing activities. This, in turn, leads to activities that are synonymous with human existence such as production, manufacturing, waste generation and disposal. As a direct result of the processes of manufacturing and disposal of consumables, there is a significant increase of the rate of pollution. This depletes valuable natural resources and also releases toxic energy which pollutes the environment, making sustainable development impossible to achieve. Sustainability as a word has always been used in our everyday lingo. According to Hideroni (2006) it is defined in a perspective of natural environmental protection, population growth and economic gap between developed and developing countries. Sustainable development entails an environmentally comprehensive, cost effective and socially suitable management of solid waste (Roberts, 2003). Sustainable development is a theory that has to be integrated into the everyday lives of the populace if we want to achieve a better quality of life for our unborn children (Dernbach, 2002). In the recordings of the International Council for Local Initiatives(ICLI),sustainable development is such that provides environmental, social and economic amenities to all citizens of the society without disrupting the capability of the natural built social systems upon which the delivery of these services depend on. The main aim of sustainable development is to regenerate the badly damaged environment and ensur e that generations unborn do not face the adverse effects of our neglect on the environment. Therefore, solid waste management with sustainable development in mind encourages countries to generate less waste, re-use most consumables, recycle and try their utmost best to recover and reuse all the waste produced, thereby ensuring that the future generation are not affected by the impacts of the current generation (Mbata 2010). Sustainable development is a concept that needs to be taken into attention for effective waste management. With regards to this, countries all over the world including Nigeria, are striving to achieving sustainability (Hasheela, 2009). Therefore, all necessary steps and precautions should be taken to achieve this goal PROBLEM STATEMENT Having a population of over 165million people and an annual growth rate of 5.6%, Nigeria is considered the largest country in Africa. Growth rate of urban areas in Nigeria has increased from 25% in 1975 to 46% in 1995(George,2010) Estimates by the World Bank indicate that by the year 2005, more than 65% of Nigerians would have migrated to urban areas such as Lagos, Port Harcourt, Delta, Calabar and Abuja (Alkali, 2005). The cause for this relocation is essentially due to oil exploration activities of oil companies in these areas. As a result of this, the wastes generated from these areas have been on the increase and its disposal and effective management is a huge challenge to the government and municipalities involved. It can be observed that the major problem associated with solid waste management comes about due to the large heaps of refuse dumped illegally by the road sides and market places (Odiba 2003). As horrid as it sounds, it is still common practise in Nigeria to dump wast e illegally without thinking of the impact of such practices on our environment. Waste management problems in Nigerian cities according to (Ogwueleka 2009) are typically associated with lack of concern and participation from the general public. He further stated that most of the waste policies are made without putting the public, who are the main waste generators, into thought. The manner, in which waste is controlled in Port Harcourt, Nigeria (the study area) is a big threat to the environment and can cause health hazards (Hasheela2009). A plethora of health hazards such as malaria fever, typhoid fever, diarrhoea, cholera and even skin diseases have been shown to be the effects of poor waste management in any environment (Guobadia 2011). It is needless to say that ineffective waste management is a big danger to the goal of sustainable development and if no positive advances are made in the area of managing waste, there will be catastrophic, long term environmental impacts on the people now and generations unborn. AIMS AND OBJECTIVES AIM The principal aim of this project is to examine and discover the various ways how the Reuse and Recycling of Municipal Solid Wastes can lead to sustainable development and revenue generation. To establish, through comprehensive analysis and statistical analysis that waste Reuse and recycling the most suitable method of Municipal Solid Waste Management in a developing country such as Nigeria and can ultimately lead to Sustainable development. Objectives To evaluate the various already existing techniques/methods of Municipal Solid waste collection and disposal in Port Harcourt city and Nigeria as a whole. To determine, based on an Environmental Risk Assessment, the most significant waste related risk currently in the case study area (Port Harcourt) To appraise the present level of awareness shown by the public and the current efforts of the government in creating more awareness and providing environmental education to members of the public on efficient, environmental friendly methods of waste disposal such as Reuse and recycling. To explore the barriers that prevents the reusing and recycling of the major components of Municipal solid waste such as paper waste, plastic waste. To deal with Solid waste reuse and recycling as important aspects of national economy and environmental as a means of sustainable development and revenue generation. Research Questions This study is concerned with achieving sustainable development and potential revenue generation through Reuse and Recycling as a method of Municipal Solid Waste Management. It will seek to answer the following: Why is there a need to reuse and recycle municipal solid waste? In what ways can Reuse and recycling of municipal solid waste lead to the achievement of sustainable development? Can Revenue generation be guaranteed through the continuous use of reuse and recycling as the core method of municipal solid waste management? 1.5 Significance of study Sustainable development is the ultimate goal of every society and should be pursued with all diligence. This research highlights the significance of municipal solid waste (such as paper glass and plastics) as useful resources through reuse and recycling towards Sustainable development and revenue generation for Port Harcourt city and Nigeria as a country. 1.6 Scope and limitation of study This project work was limited to only the processes of reuse and recycling of municipal solid waste as a means to sustainable development in Port Harcourt city. Only recyclable waste such as plastics, paper and glass were used as a case study because they are the major waste materials found in municipal solid waste in Port Harcourt. However, all other processes of municipal waste management such as composition, collection, transportation and disposal were also looked to during the course of this research. 1.7 Structure of Study Chapter 1 gives an introduction to the research, covers the background of the study, discusses its aims and objectives, and also proposes relevant research questions. Chapter 2 details the literature reviews of municipal waste management, views reuse and recycling as a means for sustainable development and revenue generation, and also the present-day situation of waste management in Nigeria Chapter 3 shows the methodology employed for achieving the set aims and objectives of the study. Chapter 4 discusses the results and draws conclusions from the data generated. Chapter 5 finally discusses the summary findings, shows the researchers conclusions and his suggested recommendations for the best way forward. d recommendations for the best way forward. CHAPTER TWO Literature Review 2.1 Definition of Waste Waste is a direct consequence of human existence and activity. It can be said to be totally unavoidable. Different definitions of waste abound. It is, however, important to state that the term waste is very subjective. This is because, what one person may consider as waste can be viewed as an object of high value by another person.(Ajomo, 2010). A very strict legal definition of waste to comply with the law is therefore necessary; as such firm definitions of waste have legal, financial and social implications for the government, local authorities, businesses, and the general public (Williams 2005). In common parlance, waste can be defined as any product or material that is unwanted. Wright (1990) describes waste as anything that has lost its utility value in the sight of the original owner and everyone else in general. However, the European Council framework Directive (waste Framework Directive 75/442/EEC 1975) offers a legal definition of waste. It defines waste as à ¢Ã¢â ¬Ã ¦Ã ¢Ã¢â ¬Ã ¦any material where the holder has an intention to discard the material as no longer part of the normal commercial cycle of the chain of utility This is the universally recognised definition of waste. Different countries may have slightly different deviations of this definition based on their laws, culture and prevailing times, circumstances and practices. According to the Federal Environmental Protection Agency (FEPA), under the auspices of Provision Decree 42 of 1988, waste is said to be substances or objects which are disposed of, or are intended to be disposed of, or are required to be disposed of by the provisions of the law of the Federal Republic of Nigeria (Omobolaji, 2010) 2.2 Classification of waste There are different types of wastes that can be found all around us. Different nations define/classify waste according to the state in which the waste is formed i.e. solid, gas or liquid or the way the waste is generated. Based on this, waste can be classified Industrial waste, household wastes, medical waste, construction waste, commercial wastes, radioactive wastes, etc. However, in general terms, all these types of wastes can be classed into two main kinds, namely Controlled and Uncontrolled wastes: Controlled Waste Controlled wastes, according to the provisions of the Control of Pollution Act !974 (COPA) are said to be mainly Household waste commercial/ industrial wastes. It is a UK term covering waste subject to a duty of care under the Environmental Protection Act of 1990. Industrial Wastes: these are wastes that are generated as a direct result of industrial practices. They include waste thermoplastics, waste wood cuttings and trimmings etc. However, they do not include plastic medical waste, waste steel cuttings and waste paper (Environmental Law Library 2010). Commercial Wastes: They are the various waste materials gotten from trade and business buildings and activities. Household Wastes: Are those waste products generated from activities inside a residential house. Examples of this kind of wastes are garden waste, paper and cardboard, glass, food remnants, wood etc. Non-Controlled waste Non controlled wastes are classified as those waste products that are not under the direct control and jurisdiction of the appropriate local authority. These kinds of wastes include wastes that are as a direct result of mining and quarrying activities, and agricultural wastes and also, radioactive wastes (Wright, 2003) Agricultural Wastes: These wastes are primarily the types that arise from agricultural activities such as livestock litter. They also include waste pesticides asbestos roofing material and also waste oil coming from machinery, chemicals with hazardous properties etc. Radioactive Wastes: these refer to waste that contain radioactive materials. They usually originate from nuclear power plants, or industries that emit radioactive substances or compounds during the course of their operations( Barnstein,2009) http://www.eauc.org.uk/image_uploads_waste/wasteclassificationframework_large.jpg Figure 2.2.1 Classifications of Wastes (Source: EAUC, 2009) 2.3 Municipal Solid Waste Management Municipal solid waste (MSWs) refers to all the solid waste generated within a given municipality. They are primarily organic and inorganic in nature and are produced in residential homes, office complex, shops, hospitals etc. Although everybody in the society has the duty to dispose of refuse in a decent manner, municipal solid waste is usually the responsibility of the local government authorities (Okogbue, 2001). Municipal solid waste is those wastes collected by metropol5ises independent of the main source of waste (Bernstein, 2009). Such wastes include household wastes; waste produced by business buildings and small neighbourhood stores. They do not, however, include waste from industrial practices or agricultural solid waste (Filemon, 2008) In the words of Robert Klein (2002) municipal solid waste refers to the assemblage, transfer, treatment, recycling, and disposal of solid waste in urban areas. The goal of municipal solid waste management are targeted at promoting the quality of the urban environment, generate employment and income, and protecting environmental health (Ogwueleka, 2009). According to Kit Strangen (2002), municipal solid waste may comprise of some, if not all of the following items: Street garbage/litter or sweepings. Household waste (usually generated from recycling and composting waste deposited by house residents at waste disposal sites). Hazardous waste (in small quantities gotten from households) Garden/green waste and Bulky solid waste also generated from households. Municipal Solid Waste management can be said to encompass all the activities that has to do with handling all the waste generated within a municipality, from the point of source, to the final point of disposal. In the words of McGraw(1993), municipal solid waste management is the discipline attendant with the control of the generation, storage, collection, transfer, processing and control of disposal of solid waste in a manner that is in accord with the best principles of public health, economics, engineering, conservation, aesthetics and other environmental considerations and that is also responsive to public attitudes Bloomberg (1989) described solid waste management as the discipline that deals with the control of generation, storage, collection, transfer, processing, and disposal of solid wastes in a manner that is in agreement with the best principles of public health, economics, preservation, aesthetics and other environmental concerns and that is also responsive to public expe ctations and outlooks. The United Nations (1997) defines solid waste management as the entire process of control and supervision of solid wastes from its point of generation to its end point of disposal. 2.4 Principles of Waste Management Solid waste management has been said to refer to all activities relating to the control, assortment, relocation, treatment and handling of solid waste in agreement with the best values of public living and other environmental considerations (Shan, 2000). Therefore, operative principles of waste management comprises of waste prevention, reduction, recycling, treatment and disposal in the environment (Shan, 2000). Failure to effectively manage waste in the environment leads to rapid degradation and it poses long term problems to everyone. Research has shown that, in order to successfully manage waste and minimise the damaging effects it has on the environment, some strategies should be adopted and implemented: Waste Recovery (waste recycling, re-use and treatment) Prevention of waste generation Environmentally friendly Waste disposal. http://upload.wikimedia.org/wikipedia/commons/thumb/1/18/Waste_hierarchy.svg/300px-Waste_hierarchy.svg.png Figure 2.4: Waste Management Hierarchy (Source: Liennmann, 2009) These strategies are aimed at reducing the overall amount of waste produced by encouraging proper management of waste. It also aims at recovering as much value as possible from all the waste generated. As shown on figure 2.4, waste prevention should ideally be the first approach to waste management before other options are considered (Klein, 2000). Effective implementation of this waste management hierarchy will lead to a reduction in the volume of the final waste disposed (Hasheela 2009). Magali and Bodart (2010) suggested that for sustainable development to be achieved, waste management activities should be dedicated towards waste reduction, which is at the top of the hierarchy, using the very practicably best environmental choices. Therefore the main aim of the waste management hierarchy is the reduction of waste at source. Waste recovery and reuse should be the secondary aim as they involve other processes such as recycling, composting, and recovery of energy. However, recent studies have shown that the waste management hierarchy strategy is not the most effective. This is because it is not based on any scientific principle.it cannot specifically choose the best system for a city or country to adopt. For example, the waste management strategy cannot equate composting and incineration; or recycling and landfilling in terms of their environmental impacts and cost (Letcher, 2004). This goes to show that the waste hierarchy should be followed flexibly as a guide rather than rigidly in order to achieve a stable environmental, economic and social solution (Raven, 2011) Aside from the above mentioned constraint, implementing this strategy in a developing country such as Nigeria will be difficult. This is because of the prevailing norms of illegal refuse disposal all across the nation. It will therefore entail adequate environmental awareness/education for the public. More so, stringent environmental laws and regulations should be implemented by all concerned. 2.4.1 Prevention of Waste Waste prevention remains the best form of waste management because it is the most effective way of reducing the amount of waste that is generated. It is also the most environmental friendly means has it has absolutely no effect on the environment. It reduces pollution, saves electricity and saves far more energy than all other means of waste prevention (Vallero, 2004). Finkbeiner (2003) stated that the number one priority in waste management should be waste prevention as it is the best way to stop the accumulation of waste and a reduction of loss of resources. This process should be started at the source of production. The primary approach of waste prevention and reduction is for the manufacturers to redesign and package their products with the lowest toxicity and least volume of material. Industrialist and households can also reduce their waste by selective buying and recycle of some products and materials (Angell, 1995). It can be said that waste reduction depends mainly on the consumers and the choices they make. As such production and manufacturing companies should adopt cleaner trends in the production process. They should also try to encouragement the consumers choice to support less wasteful products and services (CEC 2001). This can be achieved through the use of clean technology. Their ability to choose sustainable products that have the least negative effect on the environment is the key to sustainable waste management (Spoolman, 2008). 2.4.2 Recovery of Waste/Energy Recovery is a waste management method whereby the biological, physical or chemical essence of a waste product is altered in order to reduce the effect of such waste on the environment (Cheremisinoff, 2003) Energy can be recovered through various means; example chemical, thermal, physical and biological processes. Some waste management strategies for recovery of energy include: Composting: This is an environmental friendly way of decreasing the volume of waste produced and also producing fertilizer (Bertoldi, 2006). Because of the low negative impact it has on the environment, the European Union has rated this method of waste disposal very high (DEFRA, 2006). It is a microbial based aerobic method that deals with the gains of resource efficiency and creates useful products from waste material that could have otherwise been discarded (USEPA 2011). The process of composting is particularly favoured for use in the tropical and hot climate countries. This is because of the high rate of biodegradation in those regions as a result of the climate. According to Tyler and Scott (1999) almost 70% of the waste streams in developing countries are compostable. The general procedure of composting is such that the organic ratios of municipal solid wastes is isolated from the inorganic portions and then laid bare to composting, this can be done in a mechanized fashion usin g machines and tools to handle the wastes and regulate the composting conditions. Composting can also be semi mechanized in which case the composting process is allowed to occur naturally and less machinery is used. Composting also removes the organic matter in the waste stream thereby improving the recycling and incineration processes. Nevertheless, a number of greenhouse gases such as methane, carbon dioxide etc. are released into the atmosphere during this process, among other things, hence it is obvious that composting has its negative environmental impacts. Incineration: Incineration is another method of reducing municipal solid waste. It essentially entails the combustion of waste materials with the use of an incinerator under temperatures of over 1000 Degree Celsius (Environmental Protection Department, 2005). During the incineration process, solid waste is sorted out on the basis of their combustibility. Thereafter, the combustible materials among the waste are thrown into the incinerator and burnt. Incineration of waste is a highly effective method of reducing waste as studies have shown that it reduces the amount of waste dumped in landfills by up to 80% volume and weight (Roberts, 1978). However, this method is quite capital intensive and also requires high maintenance cost and technical expertise. This is why it is only popular among developed nations and countries such as Nigeria do not readily practice it (World Bank, 2002). Anaerobic absorption : Anaerobic digestion is a biochemical procedure that takes place when there is an build-up of wet organic matter, in the lack of dissolved oxygen. Through the action of anaerobic microorganisms, organic matter is converted to water, methane and new cells. These are then collected and used as gaseous fuel while the soil dregs are used as soil conditioner. Anaerobic absorption also aids processes of landfilling by eliminating sticky organic waste materials that are responsible for gaseous and liquid radiations. It is normally carried out in close tanks that allow for the collection of large portions of biogas produced (Keller, 2007) Studies indicate that this process of waste management reduces the total volume and weight of waste generated by over 25% (Jason, 2009). It is fundamental to create renewable energy from biodegradable waste, rather than contributing to climate change through the release of methane gas that occurs during landfilling and incineration (Marek, 2007) According to EA (2001), methane gas is 20mtimes more potent than CO2 as a greenhouse gas. The residue gathered from anaerobic absorption comes in both liquid and solid form. This residue is known as digestate and is used to condition the soil and also as a fertilizer. This by-product is used widely on farms in countries like Germany, Sweden, and Austria. (Hardtle,2007) propounds that about 0.46% of electricity needed in the UK can be generated through the anaerobic digestion of food waste. Unfortunately, the usage of anaerobic absorption in developing countries like Nigeria is very limited due to lack of expertise, technology and the relevant infrastructure. Landfilling: For landfilling, the solid waste is dumped and spread over the land and is left for its transformation to humus. This is attained by the biodegradation of the waste matter. Landfilling is the final step in the disposal of waste that cannot be treated or recycled, together with other residues from waste that cannot be collected, separated or handled in any other way (Nemerow,2007) There are three types of landfill carried out in Africa today, namely open or dump landfill, semi controlled or operated landfill and sanitary landfill. Open /dump landfill is the most crude form of landfilling and that is the one still being practiced in most developing countries
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