SOLID WASTE MANAGEMENT IN THE GREEK ISLANDS

Transcription

1 SOLID WASTE MANAGEMENT IN THE GREEK ISLANDS A. KARKAZI, S. SKOULAXINOY, A. MAVROPOULOS AND E. FAGOGENI EPEM S.A. Department of Solid & Hazardous Waste Management, Athens, Greece SUMMARY: The disposal of solid waste in an environmental way in the case of small and medium size islands requires a particular effort. The problem of waste management in the islands concerns many European countries that have island complexes. The Greek case is representative, since the population in the insular territory is greater than in other countries that have islands and reaches up to 15% of the total population. The aim of this paper is to present a methodology for the design of a sustainable waste management strategy applied in the prefecture of Cyclades (case study), with the use of a number of software tools in each stage of the planning. This management solution has been approved at the Prefecture and Region level and its implementation is under way by the Greek Authorities 1. INTRODUCTION The problem of waste management in the islands concerns many European countries that have island complexes. The Greek case is representative, since the population in the insular territory is greater than in other countries that have islands. Almost 15% of the Greek population lives in islands, percentage that is greater than the one of the other countries and can be compared only with this of Italy (12%) (European Commission, 1996). The Cylcades islands, which consist the case study of this paper, are a small group of islands clustered together in the Aegean in the shape of a rough circle, which comprises of 39 islands of which 24 are inhabited. In the islands of small and medium size, waste management in an environmental friendly way demands significant effort. The main problems on islands are the lack of adequate infrastructure, the seasonal fluctuations of the population that is reflected to the waste generation, the climatic conditions, the sensitivity of the ecosystems, the lack of sufficient land, the deficiency of water stock, the pollution of underground water, the costly transport of the recyclables to the mainland where collection centers exists. On the other hand, as the tourism is the main economic activity, the rational waste management (reflected in the cleanliness of coasts and streets) constitutes the main parameter that the tourists take into account for selecting their holiday s destination. Consequently, local authorities often have to make a relatively greater effort in the field of waste management than local authorities on the mainland, irrespective of the fact that islands usually have to pay more for the same result. The paper presents the methodology that has been developed for the formulation and the selection of the best waste management scenario in the Cyclades islands. This management Proceedings Sardinia 2003, Ninth International Waste Management and Landfill Symposium S. Margherita di Pula, Cagliari, Italy; 6-10 October by CISA, Environmental Sanitary Engineering Centre, Italy

2 solution has been approved at the Prefecture and Region level and its implementation is under way by the Greek Authorities 2. REQUIREMENTS FOR THE DESIGN OF WASTE MANAGEMENT-DESIGN DATA 2.1 Design data The main element, in order to design a waste management system, is the good knowledge of the profile of the area in question, as well as the prediction of the future trends. The data needed for the design can be divided into two levels: the 1 st consists of the general characteristics of the whole study area and the 2 nd the local data. The information needed for each level is: 1 st level: a) population data/ population distribution b) quantity and distribution of waste c) composition of waste. 2 st level: a) existing infrastructure for the collection, the treatment and the disposal of waste b) socio-economic data (infrastructure/gdp/ energy availability /drinking water availability etc.) c) climate conditions d) geological hydrological hydrogeological data. The inventory and the calculations that have been conducted for the islands of Cyclades show that: Up to now, no specific strategy, has been developed regarding the waste management Entire system of waste management faces problems, in the sense of temporary storage, collection, transfer, treatment, and disposal. Few recycling programs have been established and mainly are performed by private firms and on a very limited scale. No treatment of organic waste is taking place. The common practice for the waste management is the uncontrolled dumping. Almost total absence of collection services for special waste. The permanent population is inhabitants (census 2001), The municipal solid waste is of tn/year, while the inerts are of tn/year. The quantity of waste is expected to increase during the next decade by 6%. There is an important potential of agricultural and stockbreeding waste, as well as significant quantities of wastewater treatment sludge. These quantities represent 64% of the total quantity of waste, while municipal waste and inerts represent 36%. Taking into consideration that the greatest part of the agricultural waste cannot be collected and treated in an organized way, it was calculated that only 20% of these type of waste can be conveyed to organized management systems. Waste management is too expensive because productivity tends to be low. Currently, the average cost of waste management is estimated to be 98.3 /ton. At the Prefecture level the annual management expenses are 7,3Mil., which represents 0.85% of the GDP of the Prefecture. Waste management costs exceed available funds. Finally, the citizens are not sufficiently aware of risks of daily incorrect waste management. The lack of correct knowledge often bring about the rejection of correct waste management plans (NIMBY syndrome) The waste production per island, the seasonal distribution, and the qualitative characteristics of the waste are presented in the following Figures 1, 2, 3.

3 QUANTITIES (ΤΝ) ΗΡΑΚΛΕΙΑ* SXINOUSA DONOUSA ANAFI SIKINOS KOUFONISI THIRASIA KIMOLOS FOLEGANDROS KITHNOS SERIFOS ANTIPAROS AMORGOS SIFNOS IOS MILOS KEA ANDROS TINOS NAXOS MIKONOS SIROS PAROS SANTORINI Figure 1. Annual production of waste TN/YEAR YEAR TOURIST PERIOD REST OF YEAR Figure 2. Temporal distribution of waste. percentage % Liquid organic fraction combustible Recyclable Qualitative characteristics Figure 3. Qualitative characteristics of the waste.

4 3. DESIGN METHODOLOGY The methodology, that has been followed, is a top down approach that consists of three stages. Stage 1- firstly the joint management area, that will be served from an integrated management system is decided, by taking into account the geographic, environmental, socio-economic and institutional parameters. Stage 2- secondly, the potential treatment methods that could be further examined are indicated, based on the available techniques, the amount of the waste and the market issues regarding the recyclables that are going to be produced. Stage 3 - for the optimum scenario, from stage 1, the best available treatment technology, based on stage 2, is selected. The followed methodology is presented in Figure 4. Stage by stage the methodology is analyzed further down 1 DESIGN OF ALETRANATIVE SCENARIOS FOR THE MANAGEMENT UNITIES SELECTION OF OPTIMUM SCENARIO FILTER QUANTITIES OTHER KINDS OF WASTE 2.PREREQUISITE FOR THE APPLICATION FILTERING OF METHODOLOGIES CRITERIA: ENVIRONMENTAL ECONOMIC TECHNICAL SOCIAL INTENDED MANAGEMENT PLAN 3. FORMULATION OF ALTERNATIVE SCENARIOS TREATMENT & DISPOSAL Figure 4. Methodology for the design and selection of the optimal scenario. 3.1 STAGE 1- Alternative scenarios for the management areas Mainly, there are three alternative management strategies: a) single strategy: each island establishes its own management system, b) joint strategy: groups of islands are formed (joint management areas), in order to establish cooperation on waste management options c) tandem strategy: for islands close to mainland all waste can be transported to this mainland. (European Commission, 1996) The aim is to have integrated management of solid waste, in each management area, i.e. collection, transport, treatment, and disposal. However, the choice of the main strategy is influenced by many parameters. Thereat, in practice waste management in islands is a combination of the above strategies. Based on the above, alternative scenarios regarding the choice of the main strategy, have been formulated taking into consideration the following parameters: A. Production of solid waste: This parameter is linked to the population distribution in each management area. The objective is to formulate scenarios with different produced quantities. The seasonal distribution of the quantities, due to the touristic character of the islands, is indirectly included in this parameter. The critical magnitude is this case, is the quantity produced during winter, when only the permanent population is on the islands. The waste quantity produced

5 during winter determines to a great extent, the environmentally sustainable and economically feasible of a treatment facility. B. Spatial, technical and economic parameters: The second parameter is the existing ship network for the connection of the islands throughout the year. The basic elements, which incorporate the spatial distribution of the islands, are: The total quantities transported according to the selected strategy. Apparently, the larger the quantities transported, the greater the transportation cost is. The frequency of connection among the islands in each scenario. The critical factor is the frequency of connection during winter, where the connection is often difficult, due to the weather conditions in the Aegean Sea and the bad harbor infrastructure in some islands. The location of the islands in the archipelago. Not all the islands can co-operate with other islands mainly due to the absence of connection among them. Joint of islands that are far from each other is avoided, since their connection is very difficult. C. Environmental parameters: The important factor is the impact of each proposed management scenario in the environment: a) in long term b) as far as its credibility is concerned. Based on the previous parameters, four alternative scenarios, regarding the strategy, have been formulated: Scenario 1: Each island constitutes of a single management area, and consequently there are 24 management areas. Scenario 2: In this scenario, a combination of the single and the joint strategy has been followed. Hence 6 groups of islands are formulated, including a total of 20 islands. For each group, one island is foreseen to host the waste management facilities, while the rest of the islands in the group transfer their wastes to the host island. Each island of the 4 remaining constitutes of a single management area. Scenario 3: In this scenario, a combination of the single and the joint strategy has been followed. Hence 3 groups of islands are formulated, including a total of 9 islands. For each group, one island is foreseen to host the waste management facilities, while the rest of the islands in the group transfer their wastes to the host island. Each island of the 15 remaining constitutes of a single management area. Scenario 4: In this scenario, a combination of all the strategies has been followed. Hence 3 groups of islands are formulated, including a total of 9 islands. For each group, one island is foreseen to host the waste management facilities, while the rest of the islands in the group transfer their wastes to the host island. Two of the islands transfer their wastes to the mainland. Each island of the 13 remaining constitutes of a single management area. In order to select the optimum scenario among the 4 above mentioned a multicriteria method was utilized. In order this to be done, a number of criteria were designed and examined, and the relative weights were assigned (Simos, 1990). Three categories of criteria were designed and examined, each one comprising of sub-criteria, which are tabulated in Table 1 Table 1. Designed criteria. Social - institutional criteria Environmental criteria Technical-economic criteria Κ1: Accordance to the existing legal framework Κ2: Social acceptance Π1: Recovery / Material recovery rate R Π2: Landfill diversion / landfill diversion rate D Ο1 : Transfer cost Ο2 : Degree of transfer difficulty among islands

6 K1: in this criterion the compatibility of each scenario to the EU and national legislation is evaluated. The best scenario is the one that presents higher potential to meet the following targets: 1) reduction of waste, 2) recycling and recovery of materials and 3) energy recovery and utilization. Not all the islands are large enough to contain a waste facility and not all the waste amounts are large enough to make a waste treatment system environmentally sustainable and economically feasible. Therefore, the best scenario according to this criterion is the one that includes large groups of islands where large amount of waste are produced and consequently the meet of targets is more feasible. K2: in this criterion the best scenario is the one that has the acceptance of the local Authorities and the citizens. The following actors have been considered in this analysis: 1) the Municipalities, 2) the Regional administration of the South Aegean Sea, 3) the Prefecture of the Cyclades complex, and 4) NGO s. Interviews and questionnaires have been utilized in order to contact sound results. Π 1: in this criterion the material recovery rate, R, is evaluated. R, constitutes a standard for the protection of the environment that each scenario achieves, as it represent the rate of the recovered material thus the amount that returns back to productive cycle. In that stage R has been calculated by assuming that only source separation of dry recyclables in each scenario occurs. Initiatives for waste prevention and source separation can be taken regardless of the choice of waste treatment strategy. Therefore, no other treatment has been considered at this point since the aim of this stage is to select the optimum scenario regarding the management areas. Π 2: in this criterion the landfill diversion rate, D, is evaluated. D, constitutes a standard for the conformation to the EU Directive 99/31 for the sanitary landfill. The parameter D represents the amount of waste that does not end to the landfill. The same assumption as in Π1 applies here. O1: in this criterion the transfer cost of the waste is evaluated. The best scenario according to this criterion is the one where small or zero amounts of waste are transferred. O2: in this criterion the degree of transfer difficulty among the island is evaluated. Three elements are considered in order to evaluate scenarios: 1) total of waste amounts transferred, 2) waste produced during the tourist period and 3) harbor infrastructure in the island. Scenarios were evaluated using the multicriteria analysis tool ELECTRE III (Maystre et. al, 1994). According to ELECTRE III, the first in hierarchy scenario, regarding the management areas was the 3 rd one. 3.2 STAGE 2- Waste treatment strategy In that stage, for the optimum scenario the possible solutions for treatment and disposal is been examined. Not all the islands are large enough to contain a waste facility and not all the wastes amounts are large enough to make a waste treatment system environmentally sustainable and economically feasible. Moreover, not all the islands have the hydro-geological conditions to allow the establishment of a landfill or other treatment plant. Final, not all the capital and the operational costs of the treatment and disposal methods could be afforded from all the islands. The methodology used for the evaluation of the scenarios is the one developed within the framework of the research project Research for the evaluation of alternative techniques and technologies of treatment and disposal of municipal waste application in the Aegean islands, (NTUA,1997) slightly modified. The methodology consists of various steps, from which only the two first have been utilized: 1) the exclusion of alternative solutions on the basis of the composition and quantities of waste and 2) the prerequisites for the application of treatment and

7 disposal technologies. The treatment methods that have been examined are 1) composting, 2) anaerobic digestion 3) incineration 4) pyrolisis and 5) gasification Step 1: this step works as a filter in order to narrow down the number of possible treatment technologies that can be applied. The filter requires as an input waste quantities and composition for each management area. Subsequently, through an if function (excel spreadsheet) it determines whether a technology is feasible for the area based on the input data. The filter contains for each technology the minimum waste input quantity (i.e for biological treatment the minimum quantity of organic matter) for the technology to be technically and economically feasible. The minimum waste input quantity was determined based on operational data of similar facilities throughout Europe and Greece. Step 2: this step contains sever prerequisites developed for each technology. In order to develop them a number of elements have been addressed: 1) existing legislation regarding products composition and environmental impacts, 2) market issues, 3) technical issues i.e types of waste that can be treated, technology complexity etc. Based on Step 1 & 2 the technologies that can be further examined are: composting, anaerobic digestion, and incineration. 3.3 STAGE 3- Formulation of the overall strategy The results from Stage 1 and 2 are utilized here in order to formulate the overall strategy for Cyclades Prefecture. For the optimum scenario four alternatives, regarding the treatment technology, have arisen, depending on the characteristics of the management area (waste quantity and composition, market issues etc): Scenario 3- Alternative 1(3.1): Source separation, Composting, landfilling Scenario 3- Alternative 2 (3.2): Source separation, Anaerobic digestion, landfilling Scenario 3- Alternative 3 (3.3): Source separation, Composting, Incineration, landfilling Scenario 3- Alternative 4 (3.4): Source separation, Anaerobic digestion, Incineration, landfilling In order to select among the above alternatives, the procedure that has been followed was based on economic and environmental parameters, which are presented below: Capital cost Operational cost Material recovery rate, R Landfill diversion rate, D For each alternative, the capital and operational cost was calculated based on data from similar installations in Europe and Greece. For the calculation of the material recovery rate, R and landfill diversion rate, D, a Life Cycle Assessment tool, for waste management has been utilized (IWM-1 model, v. 1998, P.R. White, et.al) which quantifies the amount of the pollutants (liquid-gaseous) that are emitted to the environment due to the entire waste management system implemented and determines, the rate of the recovered material (R), the landfill diversion rate (D) and the energy that could be produced from the waste treatment. In order to make a holistic evaluation that compromises all of the economic and environmental parameters, four environmental cost- benefit indicators were developed: Capital cost over Material recovery rate - R c Operation cost over Material recovery rate R op Capital cost over landfill diversion rate - D c Operation cost over landfill diversion rate D op

8 The critical point is to accomplish a solution, which combines high environmental performance with low capital and operational costs. For the representation of the combination, four diagrams have been created. Figure 5, presents the recovery rate indicator along with the capital cost of each alternative. Low capital cost and high recovery rate, thus high R c, indicate the preferable alternative. The same rationale applies for Figure 6,7 and 8. 40% 35% 30% 25% 20% 15% 10% 5% 0% Scenario R% CAPITAL COST MEURO Figure 5. Correlation of R and capital cost - R c. 40% 35% 30% 25% 20% 15% 10% 5% 0% Scenario R% OPERATION COST EURO/TN 120,00 100,00 80,00 60,00 40,00 20,00 0,00 Figure 6. Correlation of R and operation cost - R op. 52% 50% 48% 46% 44% 42% 40% ,00 100,00 80,00 60,00 40,00 20,00 0,00 D% OPERATION COST EURO/TN Figure 7. Correlation of D and operation cost - D op.

9 52% 50% 48% 46% 44% 42% 40% Scenario D% CAPITAL COST MEURO Figure 8. Correlation of D and capital cost D c The combination of the economic figures with the environmental dimension of each alternative clearly indicates the ascendancy of 3.1, which includes source separation, composting, and landfilling. Alternative 3.1 is preferred opposite the others due to: The relative low capital and operational cost The good performance regarding the recovery of materials and the diversion from landfill 4. CONCLUSIONS To date, solid waste management at all stages of production, handling, storage, transport, processing, treatment and ultimate disposal is a social and political imperative. The aim of a waste management strategy should be to accomplish successfully a combination of the optimum economic scenario with high environmental standards together with social acceptance. The design and the selection of the waste management strategy cannot and should not be based on one of the three angles: technocratic, environmental, and economical, because it will most certainly lead to failure. The methodology presented associates modern waste management tools, which give to the designed strategy a multidimensional prospective and increased the possibilities for acceptance in Administrative and Public level. Since 2002, the Regional Administration of the South Aegean Sea, has adopted the designed waste management strategy and has began its application. REFERENCES European Commission (1997). Codes of practice for waste management on islands NTUA (1997). Methods and Technologies for the disposal of waste. Maystre L.Y, Picte J, Simos J (1994) Méthodes multicritères ELECTRE : Description, conseils pratique et cas d application à la gestion environnementale Presses polytechniques et Universitaires Romandes, EPFL, Suisse P.R White, M. Franke and P. Hindle, (1995) Integrated Solid Waste Management A Life Cycle Inventory

10 EPEM S.A, (2001) «Solid waste management plan for the Periphery of South Aegean» Study ΕΕΤΑΑ (1995) «Diagnosis of practices for the waste management and the development of management plans in the Greek islands», MEDSPA-91 1/GR/002/GR/02. Simos J. (1990) Evaluer l impact sur l invironment, Presses Polytechniques et Universitaires Romandes, Suisse