Strategical analysis is proposed as a tool for correct solid waste handling planning in a large city, such as Medellín. Four alternatives are compared and the ones favoring recycling and education are shown to be more beneficial, even from the economical point of view

1. A CONTRIBUTION TO THE STRATEGIC ANALYSIS OF ALTERNATIVES FOR WASTE MANAGEMENT IN THE VALLE DE ABURRÁ AREA, MEDELLÍN-COLOMBIA Enrique Posada INDISA S.A 2008

3. DEAD RIVER, RIVER OF LIGTHS Tales of a urban river I used to be meandering free and clean, but the city needed my ways, straightened my sluggish curves and burdened me with waste and refuse. I served it well and finally died, and now the city, grateful celebrates with Christmas lights, and though I let them cover me with them, and I look fine, I still hope for the day when they will not need artifices to admire me, and when I get to be alive again and appreciated simply as I am.

4. MORAVIA, FROM WASTE MOUNTAIN TO BARRIO The brave people They came from the country side attracted by the tempting city or running away from the ward lords or dreaming with a new world Here they found a place amidst the rubble and the smells which they proudly called home and the waste was gold for them.

5. PLANNING AFTER THE FACT Creative planning Do not be sure or surprised, anything could happen here, in this amazing city that converts a waste mountain into urban renewal while the workers travel home or while the visitors come to admire from the new cable car that flies over the crowded hills

6. LA PRADERA, A COMPLEX SITE The author, working for INDISA S.A., acted as a consultant for the direction of planning of the Empresas Varias de Medellín in 2004. This entity has the responsibility for the handling of the solid wastes for the city of Medellín and for some of the neighboring municipalities of this area of 3 million people. At the present time more the 700.000 annual tons of waste are taken to the site of La Pradera, located in very rainy location (3.000 mm of precipitation per year), with complex in topography and very far away from the sources of the waste. One of the theoretical attractives of this site was that a rail track links it with the city… but rail tracks are currently mostly out of use in the zone.

7. LA PRADERA, A COMPLEX SITE My daily journey This is the road to the Prairie. I go there in my powerful truck loaded with refuse so that the wasteful people may have their house in order and the dirt away from them. I also forget about the waste, and forgive the smells, enchanted by the views and by the green mountains that adorn my ways.

8. LA PRADERA, A COMPLEX SITE Indeed a Prairie The new land fill site deserves the name it has, because of the green beautiful lands. But the city cares little to admire, all this is far, far away and people are busy and do not have much time for poetry or similar wastes of time.

9. LA PRADERA, A COMPLEX SITE Perhaps too much beauty is taken by granted and make people unable to observe details and to keep it alive and thriving

10. LA PRADERA, A COMPLEX SITE Waters all around Water is so plenty and the mountains so generous with them, that we think that they are eternal or disposable, or defiant, so we proceed to waste the streams, taming and humbling them with careless deeds.

11. LA PRADERA, A COMPLEX SITE The region is a natural garden and deserves special care with plenty of gardeners proud and respectful, otherwise the flowers will sadly cease to be

15. PROGRAM OF EDUCATION, SEPARATION IN THE SOURCE AND RECYCLING Existence of appropriate centers for storing, dispatching and separation of waste and the availability of sufficient human resources dedicated to these activities. Complete educative programs and activities of motivation of the community, employing all the necessary mass media and other means. The model considered the costs and benefits, the human resources, the necessary areas and the investments. This educative and motivational area received and continues receiving very low attention.

16. HANDLING OF LIXIVIATES For the handling of lixiviates, coverings and drainage systems adapted for the land filling were considered, improving significantly the existing situation. The model considers the treatment of leached waters in an UASB anaerobic system plant. At the time, the lixiviates were not adequately treated and giving the lack of drainages, treatment facilities, sufficient covering and the type of terrain and the large precipitation in the site, the problem was largely unresolved. This seems to be still the situation, although some things have been done.

17. HANDLING OF BIOGASES For the handling of biogases generated, a model of available energy and gas discharge was generated. It is a function of time and of the handling of the land fill (related to the amount of deposited organic material, which varied according to the studied alternatives). A model was included to consider the costs of gathering gases and of taking them to a plant for the generation of energy or to individual chimneys for combustion. Right now a system is being put into practice, applied to burning the gases to diminish greenhouse gases.

18. HANDLING OF BIOGASES A possible thermal plant was considered in some of the alternatives. A cost model was included to estimate benefits and costs of generating electrical energy from biogas, both for external sale and internal consumption. Also, taking advantage of the availability of biogas, designs of rotary incinerators of several capacities were made that fulfilled the norms as far as temperatures, time of residence and pollution control.

19. TRANSPORT AND OPERATION A model was elaborated to consider the costs of transport of waste to the La Pradera land fill, which is about 70 km from the collection systems in the cities. That included number of trips, resources, expenses and investments in vehicles and fuel consumptions. It was complemented with another model to consider the costs of the administration and operation of the land fill, such as excavations, land value, membranes, drainages, gas chimneys and machinery. For this the model the effects of areas, average depths, densities, amounts and types of waste were included.

20. ALTERNATIVES STUDIED Alternative 1 The present situation . In this, there are no programs of recycling or separation in the source, undertaken directly by the organization, although some recycling and separation are under way done by low paid recyclers and some well organized cooperatives. At the time, a modest organic waste recovery program for elaborating compost was in place. This alternative does not include a plant for treating lixiviates nor any systems to take advantage of the energy of the gases.

21. ALTERNATIVES STUDIED Alternative 2 An improvement on the current situation. It is an alternative reachable, but implies concerted efforts and intelligence of all the involved sectors, much conscience in the city, leadership in the organization and citizen commitment. It includes a plant of treatment for lixiviates, a thermal plant to take advantage of the energy of biogases, a rotary incinerator, increasing separation in the source and of recycling programs, with strong educative components and a more intense program of treatment of the organic wastes towards composting.

22. ALTERNATIVES STUDIED Alternative 3 A more aggressive approach . It includes more demanding goals for recycling, treatment of organic and separation in the source. Treatment of lixiviates Also using a thermal plant for recovering biogas energy and a rotary incinerator.

23. ALTERNATIVES STUDIED Alternative 4 Aggressive education and source management of waste . It is a situation in which the emphasis is put mostly in recycling, treatment of organic waste and separation in the source. A lixiviate treatment plant is included. It does not consider thermal plant nor incineration to take advantage of the biogas energy, which is simply burned.

24. RESULTS OF THE MODEL Alternative 1 2 3 4 Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Waste recycling and separation No Medium High Very high Lixiviate plant No Yes Yes Yes Organic waste treatment Very low Medium High Very high Thermal Plant No Yes Yes No Incineration No Yes Yes No

25. Waste generated and treated in 20 years (million tons) Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Total generated waste 19,62 19,62 19,62 19,62 Organic treated 0,27 2,02 3,91 4,85 Recycled or separated 1,90 3,53 4,23 Incinerated 0,38 0,38 To be taken to the landfill site 19,35 15,32 11,80 10,54

26. Other operation parameters Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Open accumulated area in the landfill site (hectares) in 20 years 154 122 95 85 Biogas energy flow (year 20), million Kcal/hr 58 42 25 21 Number of trips carrying waste to the site (thousands) in 20 years 1.962 1.771 1.608 1.539 Directly Employed persons in the programs 875 1.072 1.203 1.177

27. Costs in 20 years operation (million US $) Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Total 528 673 758 770 Building and operation of landfill 480 405 340 321 Lixiviate treatment 36,4 9,3 9,2 8,1 Operation of recycling plants 25,9 48,2 60,3 Operation of plant to generate electricity 86,9 61,0 Operation of organic composting plants 7,2 49,8 96,5 119,1 Incineration 9,8 9,7 0,0 Education and community motivation 4,7 86,4 193,1 261,8

28. Revenues in 20 year operation (million US $) Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Total 1.284 1.483 1.562 1.540 Waste collection fees 1.281 1.281 1.281 1.281 Recycled material sales 65,3 121,5 151,2 Electricity sales 82,1 63,0 Compost sales 2,4 44,9 86,9 107,7 Incineration services sales 9,2 9,2

29. Results and investment in 20 year operation (million US $) Situation Actual More recycling and recovering of biogas High recycling and high biogas recovery Very high recycling and no biogas recovery Net result 756 810 804 770 Comparison with actual situation 54,2 48,2 14,7 Net result without considering waste collecting fees -526 -471 -478 -511 Total investment 38,2 66,6 59,2 49,8 New waste carrying vehicles 37,3 21,8 8,5 13,9 Plants for recycling and separation 7,8 14,3 14,3 Thermal plant to generate electricity 24,0 13,2 Plants for organics handling 0,8 10,2 20,6 20,6 Plant to treat lixiviates 1,3 1,0 1,0 Incineration plant 1,4 1,4

30. ACCUMULATED WASTE TO THE LANDFILL

31. ACCUMULATED LAND FILL SITE AREA

32. CONCLUSIONS Alternatives 2, 3 and 4, that imply programs of separation in the source and treating in some way the waste, are more attractive from the economic point of view that the present situation. In spite of the apparently high investments, the alternatives that contemplate use of biogas are more attractive than those than do not use it. It is clear that this is not really an economical problem, but a problem of beliefs and attitudes

33. CONCLUSIONS It is important to note that the proposed alternatives, besides being more economical, show also a favorable impact on direct and indirect employment, which is very important for a city like Medellín, subject to difficult unemployment and social problems. This city has an enormous potential for growth and a real need for improving the quality of life for the people. It should focus correctly its solid waste problems. It has been shown that alternatives that attack the problem from an integral point of view are more attractive than the current situation. It is necessary that a city of this importance has integral planning for handling this type of problems.

34. CONCLUSIONS A beautiful city deserves loving care It is a matter of believing in brave people like the ones recycling for us every day under difficult situations

35. Thank you very much for your kind attention