Master of Science in Environmental Management

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Browsing Master of Science in Environmental Management by Subject "Civil Engineering"

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    item: Thesis-Abstract
    A Study of the present status of management of PCBs, and development of a preliminary inventory for PCB contaminated transformers in Sri Lanka
    Panditharatne, CR; Ratnayake, N
    Polychlorinated biphenyls (PCBs) have wide applications and one of its main uses is as the dielectric fluid in electric equipment. During 1970s PCBs were identified as a substance dangerous to health and environment and was banned in most countries since 1980s. Assuming that 60% of its uses are as dielectric fluid in electrical equipment, this survey was concentrated on transformers. In Sri Lanka, CEB, LECO, LTL are the main service sector stakeholder agencies that own and manage transformers and capacitors that could be contaminated with PCBs. Other than these institutions there are transformers owned by private sector users. Small scale recyclers also handle transformers for smelting of copper and recycling of waste oil. The objective of this study is to estimate the extent to which there are PCB contaminated equipments in the country; to identify issues faced by stakeholders and to provide recommendations for the management of PCB contaminated equipment. Questionnaires, surveys and field visits were undertaken for the collection of information. In the survey, information about transformers manufactured on or before 1986 were collected. There are 14,354 transformers owned by CEB and 2700 owned by LECO. In the survey, 354 in-use transformers and 296 decommissioned transformers were investigated. 118 In-use transformers were tested with the Dexsil Field Test Kit and 52 decommissioned transformers were tested. Dexsil Field Test Kit was used to eliminate PCB negative transformers. In Sri Lanka, there are a few pure PCB transformers, but a considerable potion of contaminated mineral oil transformers exist in the country. According to the findings of the study, with 95% confidence level, it can be stated that 73% to 56% of in-use transformers in the population are contaminated with PCBs, while at the same confidence level, 78% to 52% of decommissioned transformers are contaminated. There are several HS codes under which PCB oils, contaminated material and waste oils could be imported to Sri Lanka. There is no legal requirement for a 'PCB free certificate'. Possibility of informal recyclers being contaminated with PCBs is quite high because there are no controls over disposal of PCB contaminated transformers. Recyclers are completely unaware about the hazards of PCBs. Storage of contaminated transformers/material is not environmentally acceptable and there is a high possibility for environmental contamination. Main recommendations of the study; 1. Establishment of a complete Inventory and a Database on contaminated transformers. 2. Identify all Pure PCB transformers and have a phasing out plan. 3. Establish procedure for Operation and maintenance of contaminated transformers to prevent further cross contamination. 4. Prevent new entry of contaminated capacitors, transformers and oils to Sri Lanka 5. Proper disposal of decommissioned transformers. 6. Establishment of proper storage; identification and remediation of contaminated sites. 7. Establishment of necessary regulations for the implementation of the above.
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    item: Thesis-Abstract
    Strategies for the improved management of coastal zone of Sri Lanka
    Dissanayake, UAPK; Hettiarachchi, SSL; Samarawickrama, SP
    Sri Lanka has a fully operative Coastal lone Management Plan (ClMP), which is periodically updated. The 2003 Coastal lone Management Plan has followed and built upon the 1997 Coastal lone Management Plan with additional components introduced to address the current requirements. However, some areas have not been addressed in great detail even in ClMP 2003. The Costal Erosion Management Plan does not include green engineering measures and the Conservation Plan does not include the Estuary and Lagoon management in depth .It has been emphasized that a national recommendation regarding policy design is inappropriate and site specific policy design is required. Fisheries concerns, which were not addressed earlier, are included in ClMP 2003. Extending the SAM process. to all areas requiring site specific and integrated sustainable resource management are key objectives in the ClMP 2003. Sea level rise is one of the more certain responses to global warming and presents a major challenge to human kind. The average global sea level rise estimated by IPCC is at 31 em to II0cm by the year 2100 with a best estimate of 66cm. The land loss estimated using the simple drowning concept on the southwest coast is 6.0 to 11.5 km2 when the low and high scenarios of sea level rise are concerned respectively. In assessing the vulnerability to sea level rise the new techniques such as GIS, Remote Sensing and Aerial Video Tape assisted analysis should be used. Brunn Rule is another very widely used technique to assess the land loss. It has been estimated that the Coastline of Sri Lanka will recede by as much as 50 to 500mwithin the next century purely due to rise in sea level. Therefore, it is extremely important to pay attention to sea level rise in the future in the design, planning and implementation stages of coastal development, coastal protection and coastal management activities. The estuary management plans should be consistent with the tenets of total catchment management and ecologically sustainable development. It is important to realize that basic methods to understand the distribution of pollutants in estuaries can be a management tool and an aid in decision-making but nothing more. The recommended ratios of nutrients in estuaries are given by Redfield Ratios, however, a review of the literature indicates that optimum N: P ratio can vary between seven and eighty-seven. The greatest uncertainty with estuary nitrogen budgets concerns the contribution of atmospheric deposition. The principal management objective identified for Sri Lanka is conserving lagoons and estuaries to sustain and enhance environmental functions of and promote socio-economic activities connected with them. Three budgets were created for Negombo estuarine system using CABARET. The one layer I box budget indicates that the system is net heterotrophic and denitrification is dominant. The 2 box I layer budget indicates that the estuary is net heterotrophic in the wet season. In the dry season the system box I is net autotrophic while system box 2 is net heterotrophic. In 2 box I layer system too denitrification is dominant in the estuary both in wet and dry seasons. In the 3 box 1 layer model there are some regions in the estuary, which are autotrophic while rest of the regions, are heterotrophic. And in some region nitrogen fixation is the dominant process. Therefore, it is more suitable to use a multiple box model to understand the nutrient pollution problems and biogeochemical processes in the estuary. From the types of management programmes, which have been adopted globally, the use of an effective Integrated Coastal Zone Management Framework is most relevant to the management of Coastal zone of Sri Lanka. When compared to applications of management frameworks from different countries, legal, institutional and organizational requirements are not a serious problem in Sri Lanka. Community based approach which is already in use should be extended and management tools such as GIS and Vulnerability Assessments should be incorporated into the ICMF.