pelican.jpg (333200 bytes)   A Bird's Eye View on Waste

Waste Management

Conference Programme

 
An Overview of Solid Waste Management
in Economically Developing Countries
 
by Luis Diaz
President CalRecovery Inc., USA

 

1. Abstract

Inefficient collection methods, insufficient coverage of the collection system, combined with improper disposal of municipal solid wastes and contaminated sources of water supply, are major threats to public health and environmental quality in developing countries. This paper presents a review of some of the most important technical and non-technical issues confronting developing countries in the management of their solid wastes. Some of the non-technical aspects include costs, policy, institutional aspects, and regulatory matters, as well as human resources. The paper summarizes some of the most important problems and proposes and some solutions.

2. Introduction

Recently, protection of public health and of the environment by utilizing proper methods for the management of municipal solid wastes is gaining importance in economically developing countries (DCs).

Inefficient collection methods, insufficient coverage of the collection system, combined with improper disposal of municipal solid wastes and contaminated sources of water supply, are major threats to public health and environmental quality in DCs. Although these threats have been evident for several years, historically, pollution control and environmental management have been given little or no attention in many DCs. On the other hand, governmental policies have concentrated on industrial development. Recently, however, environmental quality in many urban areas in DCs has deteriorated to such a degree that it can no longer be ignored. This situation has resulted in a substantial concern and intensification of efforts to find and apply methods of reversing the trend and of raising environmental quality to an acceptable level.

3. Data Collection and Planning

Two of the most important issues associated with data collection and planning in DCs are: 1) the lack of trained personnel (both technical and professional); and 2) the need for accurate, relevant data.

3.1. Lack of Trained Personnel

The majority of educational institutions in DCs do not offer curricula in solid waste management. This neglect results in a severe lack of properly trained human resources necessary for the planning and implementation of waste management systems. Consequently, DCs generally must rely on the services of advisors from industrialized countries.

External advice will not be useful unless the advisors are aware of the considerable differences in the conditions (social, cultural, financial, and environmental) and in the characteristics of the waste between DCs and those of the native country of the advisors. The end result is that alternatives and technologies that are acceptable and practical in an industrialized country seldom are directly applicable to conditions in a developing country. Either the technologies must be modified, usually substantially, or they may in fact be completely incompatible. Attempts to directly transfer technology and practice from an industrialized nation to a DC usually do not meet with success and frequently fail. These efforts are the result of a lack of understanding of the local conditions in DCs. An understanding of the conditions requires the collection of basic key data, as well as a thorough knowledge of the social, cultural, financial, and environmental conditions prior to the preparation of any type of plan.

3.2. Need for Basic Information on Solid Waste

Some of the most important key information include quantity, composition, and characteristics of the waste generated in the country. Furthermore, data should be collected on existing waste management practices in the particular country, e.g., storage, collection, treatment, final disposal, availability of equipment, maintenance procedures, availability of human resources, budget, and sources of revenue. These data should be collected by experienced and trained personnel. If there is not sufficient time for collecting data in the field, then the data can be obtained from reliable sources and should be critically evaluated. A critical evaluation of the information is extremely important because it enables a determination of the accuracy of the information and subsequently justifies any needed modification to the data as a consequence of the evaluation.

Waste characterization is an important element in the development of a reliable and sustainable solid waste management program. One reason is that successful management and processing of wastes depends on the types, quantities, and composition of the material. Waste generation rates and composition vary substantially among developing countries, as shown by the data in Table 1. Wide variations are apparent from observation of the data in the table (for example, the percentages of putrescible matter, paper, glass, and plastics/rubber/leather).

Table 1. Composition and Generation Rates of Solid Waste in Selected Developing Countries (% wet wt unless otherwise noted)

Location

Putres-cibles

Paper

Metals

Glass

Plastics, Rubber, Leather

Textiles

Ceramics, Dust, Stones

Gen. Rate
g/(cap-
day)

Bangalore, India

75.2

1.5

0.1

0.2

0.9

3.1

19.0

400

Manila, Philippines

45.5

14.5

4.9

2.7

8.6

1.3

27.5

400

Asunción, Paraguay

60.8

12.2

2.3

4.6

4.4

2.5

13.2

460

Seoul, Korea

22.3

16.2

4.1

10.6

9.6

3.8

33.4

2,000

Mexico City, Mexico

59.8

11.9

1.1

3.3

3.5

0.4

20.0

680

 

Source: Diaz, et al. 1996

The relatively high concentration of putrescible matter in the wastes generated in DCs (22% to 75%) results in moisture contents and bulk densities of waste that are significantly greater than those typically found in industrialized countries. The bulk density of residential wastes in DCs varies from about 180 to 390 kg/m3. The average density of wet organic matter ranges from 480 to 565 kg/m3. Since the bulk density is sensitive to the amount of moisture in the waste, care must be exercised in the collection and reporting of this type of data.

The amount of information concerning waste composition depends upon the type of treatment system to be used for waste processing and the method of final disposition. For instance, if landfilling is going to be the major means of final disposal in a developing country, then the preparation of a waste management plan would rely primarily on information on the types (e.g., residential, civic, commercial, and industrial) and quantities of waste to be disposed. Only a superficial understanding of the composition of the waste would be sufficient. On the other hand, in the event that resource recovery and recycling are critical components of a waste management plan, detailed information regarding the characteristics of the waste (e.g., composition, bulk density, and moisture content), as well as quantities, would be a necessity.

4. Storage, Collection, and Transport

Even though the use of information obtained in one region or country and the application of this information to other regions or countries is technically inappropriate, there are some important similarities in some of the activities pertaining to storage, collection, and transport of solid waste. The generalities presented in the following sections are based on firsthand experience gained by the authors in the course of several assignments carried out by them in several DCs in Asia, Africa, Central and South American, and in the Caribbean, as well as observations made by others in various DCs.

4.1. Containers Used for Storage

Containers used for the storage of solid wastes typically have a variety of shapes and capacities, and are fabricated from several types of materials. The type and appropriateness of the container typically reflect the economic status of the waste generator. Types of containers include baskets, cardboard boxes, plastic bags, and metal or rigid plastic containers. The wide variety of container types and shapes commonly encountered within a community creates difficulty in establishing and operating an efficient solid waste collection system.

Several communities utilize communal containers (bins). The containers generally are constructed of metal or concrete. The use of communal containers may result in a reduction of the cost of waste collection, and can be effectively used to keep the problems related to the lack of storage space onsite to a minimum. Unfortunately, there are a number of problems inherent in the use of such communal containers. Some of the problems include: 1) removal and transfer of the wastes from the container to the collection vehicle may be difficult and time consuming; 2) if the bins are not properly sized or emptied on a regular basis, the contents may be set on fire or the wastes may be discharged around the containers; and 3) the waste in the containers may be accessible to scavengers and animals.

Because of the lack of collection service or of infrequent collection in densely populated areas and in human settlements, it is common practice to use street corners, vacant lots, ditches, canals, and rivers as disposal sites.

4.2. Collection and Transport

A wide range of methods and equipment is used for the collection of wastes. The methods vary from labor-intensive to fully mechanized. Types of equipment and vehicles vary from simple hand-drawn carts and wagons to modern compaction vehicles.

Generally, a collection crew consists of three or four workers, although crews of as few as two or as many as eight have been observed. In some locations, the number of people working in a particular vehicle may be increased by unauthorized individuals who take part in the collection activity in order to recover materials from the wastes. The collection activity is characterized by excessive handling and the use of inefficient methods. This results in high collection costs.

Compactor trucks, both rear and front loaders, are found in many developing countries. The use of compactor trucks is becoming increasingly popular, despite the fact that generally little, if any, additional compaction occurs in the vehicle, since the loose wastes already have a relatively high bulk density. In addition, some complex features and consequences are associated with the use of compaction vehicles, some of which may not be evident or considered at the time that the vehicle is purchased. Some of these features and consequences are: 1) the importance of matching the compaction chamber to the truck chassis; 2) the possibility that the loaded weight of the truck exceeds the bearing capacity of streets and roads; 3) inaccessibility of the vehicle to remote areas and narrow streets; 4) the need to have proper machinery and equipment, as well as trained personnel to conduct repairs and preventive maintenance; and 5) the need for a supply of spare parts to maintain the regularity of the collection service.

Despite the fact that it has been amply demonstrated that the implementation of sound preventive maintenance is absolutely necessary to maintain a collection fleet in proper operating condition, neglect of preventive maintenance is a common situation in DCs. Generally, maintenance is carried out only after a catastrophic failure of the equipment. A maintenance program is extremely important since collection and transport account for a substantial fraction of the total cost of the waste management system. Due to the absence of maintenance programs, those responsible for dispatching the vehicles to their respective routes generally are not aware of the exact number of vehicles available on any given day.

In developing countries, frequency of collection varies from daily to monthly. In some locations, particularly low income areas and human settlements, waste collection is provided only on special occasions, such as during cleaning campaigns.

In most situations, collection routes are not firmly established. It is a common practice to leave the decision for the route to the discretion of the driver. Consequently, it is common for a particular vehicle to arrive at the disposal site only partially loaded due to inefficient routing.

In some instances, an indirect route is taken to the disposal site in order to discharge part or even the entire load for use as animal feed or for salvaging some of the materials that may have some monetary value.

5. Resource Recovery

In this presentation, the term "resource recovery" is used to mean the recovery of materials discarded as wastes, and to the institutional arrangements leading to resource recovery (for example, scavenging and governmentally or industrially operated enterprises). Scavenging is the process through which materials are recovered by entities not sanctioned by the government.

The following three factors generally contribute to the practice of resource recovery in developing countries: 1) Economics – a relatively undeveloped economy of the country; 2) Material and Energy Conservation -- shortage of inexpensive raw materials which are essential to local industries, lack of affordability or production capacity for items that can be remedied by recovery of useable materials from wastes, and shortage or cost of energy; and 3) Soil Conservation -- soils that are of low quality or that are being rapidly depleted of organic matter.

Resource recovery is an advisable policy for developing countries because it usually: 1) catalyzes the development of organized, systematic waste management; and 2) leads to a reduction of the amount of wastes that require disposal. Furthermore, resource recovery provides a source of income for a relatively large number of people in the lower economic sector. Finally, if the system is properly planned, implemented, and administered, some of the revenue obtained from the sale of the materials can be used to defray a part of the cost of waste management.

5.1. Economics

The status of the economy of a particular region or country plays a critical role in all aspects of resource recovery. Since the economic situation is most DCs leaves them with little or no access to capital to import raw materials, one alternative available is to conserve raw materials by recovering and recycling materials manufactured from them. This approach is worth consideration and implementation despite some reports that indicate that recycling a material would be more costly than importing it. Careful analysis of such reports shows that in most DCs, the findings and conclusions are based on questionable assumptions and on a short-term outlook rather than on a long-term horizon (Ervin and Washburn, 1981).

5.2. Material and Energy Conservation

The majority of developing countries lack one or more of the raw materials (e.g., iron ore, bauxite, or petroleum) which are important for economic development. The relevance of this situation is that if a satisfactory substitute cannot be found, the complete depletion of a raw material leads to the cessation of all manufacturing and usage based upon that material. In addition, even though there may be potential substitutes, the substitutes may lack an important property or characteristic. For example, a particular type of plastic may not be as durable, or may not have suitable thermal properties. Even a suitable substitute is subject to eventual depletion. For example, plastics are manufactured from non-renewable fossil fuels.

The implementation of a resource recovery program may postpone depletion or contribute to industrialized development by supplying secondary materials to manufacturing industries. Materials that typically are recovered from solid waste and recycled into primary manufacturing industries include some of those listed in Table 1, namely paper, metals (especially aluminum and steel cans), and plastics.

Energy can be recovered from solid wastes by using one of two methods. One is to recover and recycle materials that can be substituted for those that require a substantial amount of energy to process and manufacture into consumer products. The second method is to convert the chemical energy of waste into a usable form (e.g., through biogasification or thermal conversion) (Diaz, 1976; National Academy of Sciences, 1977; Diaz, et al. 1984).

5.3. Soil Conservation

Most developing countries are highly dependent on agriculture for subsistence and for economic development. Therefore, conservation of soil quality and maintenance of soil productivity are very important concerns. Two of the main causes of loss of productivity of soil are erosion and inadequate organic matter content (Carter, 1980; Pimentel, et al., 1976; and Youngberg, 1980). Erosion removes the productive layers of the soil and leaves a layer that basically lacks plant nutrients. Furthermore, the structure of the exposed layer is such that it impedes plant growth and is resistant to tilling.

The organic matter in the soil provides plant nutrients and contributes to a number of desirable characteristics to soil. However, since organic matter is transformed continually during the process of cultivation, the organic matter must be periodically replenished. The organic matter in solid waste, after having been adequately recovered and processed, can serve as a replacement for the organic matter in soil. Putrescible material, such as residues from food preparation and market wastes, which are found in relatively high concentrations in the solid waste of most developing countries as indicated in Table 1, can be easily converted to a soil amendment

6. Implementation of Resource Recovery

Resource recovery from solid waste can be implemented at two levels: 1) manual recovery (scavenging) by individuals before collection, treatment, or disposal of the solid waste; and 2) a combination of manual and mechanical processing carried out on a relatively large scale and according to a governmentally sanctioned plan.

The term "scavenging" usually is applied to the first of the two levels of recovery. The second level is typically termed, "conventional resource recovery."

6.1. Scavenging

Scavenging is a process that is well established in developing countries. In fact, scavenging is such a strong part of the waste management system that attempts made to abolish the practice in some cities in DCs have been met with strong resistance. Some scavengers roam the streets looking for items that can be reused, and are known as "itinerant." Other scavengers conduct their activities at the disposal sites and limit their activities to the collection of one or two materials (e.g., paper, metal objects).

Generally, scavengers have an agreement with a "middle-man." The middle-man is an individual who: 1) has the contacts with the end users; 2) can process, prepare, and sell the quantities of materials desired by users; and 3) provides the scavengers with compensation and, in some cases, a collection vehicle (e.g., a cart or tricycle). In some locations, the solid waste collection crew conducts its collection activities as well as some scavenging of materials.

Generally, the families and social backgrounds of scavengers are such that scavenging is the only option available to them to earn a living. The work of a scavenger is difficult and has little reward. Scavengers can work up to 12 hours each day in order to earn money sufficient only to survive. In addition, scavengers often live at or in the vicinity of the final disposal site, under unhealthy conditions.

In most developing countries, scavenging plays an important role on the economic survival of a number of industries (e.g., steel, pulp and paper). Despite its disadvantages, there are a number of reasons for allowing scavenging. Based on studies conducted by the authors, scavenging should not be prohibited without providing alternative means of supporting the displaced scavengers and without taking the necessary steps to avoid, or at least reduce, any adverse impacts on industrial activity and the economy.

6.2. Mechanized Resource Recovery

The implementation of complex, mechanically-intensive resource recovery installations requires sophisticated control systems and a well-trained workforce. These are requirements that generally do not adapt to situations that are common in developing countries. Consequently, it is unfortunate to observe the trend among some of the larger cities in developing countries that are attempting to put into practice complex resource recovery processes. These technologies usually are adopted from industrialized countries. Unfortunately, technologies that are directly transferred from industrialized countries to developing countries generally cannot succeed without substantial modifications, taking into consideration the waste characteristics of the developing countries, the implementation of extensive maintenance programs, and ready access to capital for spare parts.

Some examples of technologies that have been directly transferred from industrialized countries to developing countries include large-scale incineration systems, the production of refuse-derived fuel, and in-vessel composting. The degree of success of large-scale incineration systems depends upon the concentration of dry, combustible matter in the solid waste. Such content is extremely low in many developing countries, where the waste has a high moisture content. In these cases, a supplemental fuel would be required to sustain combustion. Hopes for successful implementation of complex, highly mechanized systems for composting almost inevitably are frustrated by the failure of the compost system to perform adequately (due to low yields and high operating costs) and by unrealistic expectations with regard to markets and prices for the finished compost.

Some of the more important conclusions that can be drawn from the record of unsuccessful attempts at direct transfer of resource recovery technology to developing countries are listed below.

  1. Waste reduction, source separation, recycling, and the use of processing systems which rely on a combination of manual and some mechanical segregation are feasible and cost-effective approaches.
  2. Given the current conditions of most developing countries, complex and maintenance-intensive resource recovery operations generally are not feasible.
  3. The capacity and willingness to pay for the construction, operation, and maintenance of a particular technology should be among the first issues addressed when considering implementation of a complex resource recovery system.

7. Final Disposition

Currently, the majority of solid wastes generated in developing countries are disposed in open dumps. Most of the open dumps lack the proper equipment and trained personnel necessary for conducting the operation in a manner such that the public health and the environment are protected. There are very few modern landfills in developing countries, and most of them are not designed or operated as sanitary landfills. Since few resources usually are devoted to final disposal, the operation of the dump sites simply consists of discharging the wastes and spreading them on the land in an uncontrolled fashion. In addition, most of the disposal sites do not use modern construction methods such as small working face, bottom liner and leachate control system, and landfill gas control system.

8. Costs

The poor and inefficient management of municipal solid wastes in most developing countries leads to relatively high costs for the services. The authors have determined that in several municipalities, the costs associated with waste management can account for as much as 30% to 50% of the entire municipal budget. Furthermore, in some cases, it is apparent that the management of solid waste is used to meet political objectives. For example, a substantial labor force for waste management substantially larger than that which normally would be required may be approved to gain political favor.

Since the costs associated with the provision of the services involved in waste management generally are substantially high, in most instances the municipality (or the central government) must subsidize a large percentage of the cost. The users (or beneficiaries) of the service rarely pay service fees.

Finally, some of the most important reasons for the inordinately high cost of solid waste management in developing countries are a shortage of trained personnel and the absence of adequate and comprehensive planning.

9. Development of a National Policy

Local government units in developing countries cannot develop and implement reliable, efficient, and cost-effective solid waste management programs without clear national goals and priorities. In the development of goals and priorities, consideration should be given to some of the usual basic requirements in solid waste management, such as the provision of waste collection services to the entire population (including the urban poor), the application of waste reduction and waste minimization measures, the implementation of recycling programs, and the improvement of final disposal procedures.

The national policy should be developed through the establishment of a national committee, composed of representatives from both the public and private sectors and in close consultation with the public. It has been demonstrated that no government policy or strategy will be successful without the full acceptance and cooperation of the public (the end users of a solid waste management system). In order to be politically sustainable, the development of a national policy should be based on realistic goals, taking into consideration the social, political, cultural, and economic conditions and limitations of the country.

Furthermore, the national policy should clearly define the roles and responsibilities of the various government entities and other pertinent organizations in order to avoid overlap, inefficiency, and controversy. A clear message should be included on the roles, responsibilities, and rights of the users of the system.

The national policy should instruct the responsible entities to elaborate and enforce an appropriate regulatory and legal framework which would allow those involved in the implementation of the policy to achieve and maintain the goals.

10. Institutional Issues

Some of the most important institutional issues associated with the management of municipal solid wastes that have been observed in several developing countries include the following: arrangements for the management of the waste, organizational procedures, and the structure and capabilities of the institutions responsible for planning and conducting the work.

10.1. Institutional Arrangements and Integration of the Sector

One of the most important steps toward improvement of the solid waste management system in several developing countries deals with major modifications to organizational structures and improvements in the area of human resources of the local governments. Typically, the organizations associated with solid waste management are poorly organized and lack the hierarchy and importance that other public services (such as water supply and public works) are given. Generally, local governments are accustomed to receiving assistance from the central government and do not make any efforts to improve their MSW management capacity. Consequently, local governments may require assistance in the establishment of a specific department or authority to deal with solid waste management issues. The degree of autonomy between local government and central government may depend upon the size and degree of development of the particular city. Neighboring, small municipalities may decide to jointly establish a regional organization in order to deal with their solid waste management tasks.

As the various departments or agencies are established, it will be necessary to systematically review and clarify the various roles played by other entities involved in municipal services, such as drainage, sewerage, and roads, in order to avoid overlaps and to promote efficiency.

10.2. Decentralization

Typically, local governments are responsible for the collection and disposal of the wastes generated within their jurisdiction, as well as for the operation and maintenance of their equipment. However, local governments usually lack the authority and resources to provide a satisfactory and economically viable service. Effective and efficient solid waste management depends upon an equitable distribution of responsibilities, authority, and revenue between national government and all local governments.

Consequently, decentralization of the authority in solid waste management should be accompanied with a similar apportionment of administrative and financial control, as well as the capacity to plan, implement, and operate all of the systems necessary to provide a satisfactory service. This process should include a definite improvement in the procedures for the preparation of budgets. Budgets should be prepared based on actual and realistic costs and looking toward obtaining the necessary level of funds to provide the service. Decentralization is an excellent approach to dealing with solid waste management issues; however, if decentralization is not properly planned and implemented, it will not work and will simply lead to additional bureaucracy.

10.3. Planning and Management Methods and Procedures

The majority of developing countries do not have any type of planning or management methods applied to solid waste management. Countries that have planning methods do not apply them in a practical and efficient manner. In order to reach acceptable levels of solid waste management service, as well as to increase the efficiency of the system, local governments must give special attention to financial and strategic planning methods. Financial planning should include budget planning, cost accounting, and financial analysis. Furthermore, system efficiency can be substantially improved by implementing a management information system (MIS), conducting waste characterization programs, establishing procurement procedures, and developing simple and cost-effective methods to monitor the performance of the entire solid waste management system.

10.4. Capacities of Local Waste Management Institutions

A large number of municipalities in developing countries have serious deficiencies in their capacity to provide efficient and acceptable solid waste management services. Most of the staff assigned to deal with solid waste matters are not adequately trained and lack the most basic preparation to work on the problem. Another serious difficulty faced by solid waste management organizations in developing countries is the impact brought on them by changes in government. Generally, a change in local government results in entire changes in personnel and the rejection of policies and systems implemented by previous administrations.

Therefore, high-ranking officials in local government must understand the importance of solid waste management and its relationship to the protection of public health and the environment. Once that is accomplished, a well-conceived and highly-effective training program should be developed and implemented. The training program must be very specific and must require the participation of only staff with sufficient preparation to participate in such program.

Finally, the establishment of a professional association for solid waste management can play a critical role in the improvement of the sector.

10.5. Private (Formal and Informal) Sector Participation

Private enterprises can provide efficient and cost-effective collection, transfer, processing, and final disposal of solid waste in most developing countries. However, the participation of the private sector must take place within a certain framework; otherwise, the benefits of its participation may not be realized. This framework includes: 1) availability of adequate supervisory capacity in the local governmental institutions, 2) competitive and transparent bidding process, 3) availability of private companies having the technical and financial resources to provide the desired services, 4) availability of appropriate regulations, and 5) the existence of a clear and well-prepared contract between the local government and private entities.

In general, a local government should carefully analyze the options and decide whether or not privatization of all or part of the solid waste management system should take place. Privatization should result in an improved service at a similar or lower cost than that achieved through a municipal service. It is important that specific solutions be determined for each community; copying or adopting solutions specifically developed for industrialized countries generally will not be either successful or sustainable.

10.6. Community Participation

It has been demonstrated on many occasions that no system for the management of solid waste will be successful without the acceptance of the system by the majority of the community. It is, therefore, imperative that municipal authorities and solid waste managers seek and obtain the participation of the community during all stages of the planning process. Feedback from community leaders, and eventually from as many members of the community as feasible, should be obtained before a system for the management of solid wastes is defined and implemented. This is particularly important in locations where low-cost, labor-intensive solutions are sought and in which a high level of user participation may be required.

The support of non-governmental organizations, particularly those knowledgeable of the socio-political conditions of the area, may be instrumental in securing community participation.

11. Regulatory Matters

Improvements in the provision of the solid waste management service depend upon the existing systems of administration and urban planning. Generally, it is necessary to prepare a realistic comprehensive plan. The plan can have several names: master plan, action plan, strategic plan, and others. Regardless of the name given to the plan, it should include accurate information on the type, quantity, and quality of the waste. In addition, the plan should set goals in terms of collection coverage, degree of waste reduction, levels of recycling, etc. The plan can be implemented only within a certain legal and regulatory framework. This framework should be comprised of a set of ordinances, laws, and regulations concerning the management of solid wastes. The laws should include appropriate responsibilities for enforcement and inspection.

Currently, most developing countries have extremely basic and ineffective laws associated with solid waste management. In general, the laws simply indicate the responsible agency and that this agency must collect and dispose of the waste. Thus, existing laws and regulations must be modernized in a practical manner. The modernization process should be carefully carried out so that changes lead to improvements in the current conditions but do not necessarily result in a financial burden to the community. The modernization process of the legal and regulatory framework should also avoid copying regulations from industrialized countries. This is a practice that has been conducted in a few instances and has led to costly investments and goals that are difficult to achieve.

12. Human Resource Aspect

In most developing countries, there are no well-established and reliable information systems dealing with solid waste management. Consequently, it is difficult to know with any degree of accuracy the actual number and qualifications of the personnel working in solid waste management. However, based on the authors’ experiences, it can be estimated that the average number of workers in the solid waste sector in large cities is between 0.5 and 0.9 per 1,000 inhabitants. It is possible that the average number of workers is lower than this range in medium and small cities. This number does not include a relatively large number of people who conduct recycling activities (both formally and informally).

With only a few exceptions, primarily in the large cities, most of the personnel who participate in the solid waste sector have received minimum or no training. This is true for both the professional and technical levels. In addition, the average age of the laborers is very high. Typically, laborers in the solid waste field are not provided with adequate equipment to perform their duties, very few of them are given safety protection equipment, and most of them are not motivated to perform their tasks efficiently.

13. Summary and Conclusions

In most developing countries, the management of municipal solid waste has traditionally been a primary responsibility of local governments. In a large number of medium-size municipalities, the management of MSW can use between 30% and 50% of the total municipal budget. The majority of urban centers are not properly managing their municipal solid wastes. A substantial percentage of the wastes remains uncollected. The wastes that are collected generally are disposed in open dumps.

Although the solid waste management situation described is one of many shortcomings, conditions are beginning to improve. Municipal officials and decision-makers have become cognizant of the dangers and problems attending improper management of solid waste and of the need to initiate remedial measures. Background studies and surveys are being conducted, and courses of action are being prepared. Especially important, plans are beginning to be implemented. The prospects for success will depend upon the use of means best suited to the capabilities of the countries and their people.

There are a number of issues that should be addressed to appropriately deal with the solid wastes generated in developing countries. Isolated investments in equipment and technology do not address the key issues, and generally the investments are wasted. For investments in equipment and in technology to be successful and sustainable, they must be preceded by investments in the following areas: development of a sound, reliable, and achievable national policy; preparation and implementation of adequate institutional arrangements; issuance and enforcement of appropriate and modern regulations; and motivation and training of human resources.

Luis F. Diaz, George M. Savage, and Linda L. Eggerth

CalRecovery, Inc.
725C Alfred Nobel Drive
Hercules, California 94547
USA