Integrated Solid Waste Management for Local Governments: A Practical Guide

INTRODUCTION

A member of a waste cooperative cleans discarded plastics for recycling. Photo: ADB

Integrated Solid Waste Management for Local Governments: A Practical Guide is a compendium of more than 40 practice briefs that has been prepared to assist both municipalities and Asian Development Bank (ADB) staff on the key issues in contemporary solid waste management.

The briefs are based on experience gained from the regional technical assistance project, Mainstreaming Integrated Solid Waste Management in Asia. The lessons learned from studying the five cities under this technical assistance were collated and supplemented with general industry experience of the consulting team, ADB staff, and external reviewers. Case studies from the five cities are also part of the overall knowledge package, providing specific guidance on the likely issues and lessons learned from individual city investigations.

The aim of the practice briefs is to provide easily accessible information in a very targeted manner, with links to resource documents should the reader wish to obtain more information on a topic. The products are written in reasonably plain English to encourage access by a broad cross section of users and not just waste management professionals.

The practice briefs are grouped into the following categories:

(i)Solid waste management planning. This group of practice briefs provides information on the types of waste characterization audits that may be required and a number of recommended methodologies to ensure that statistically valid data are obtained for subsequent input to any planning activities. Competent waste management studies do not just address the collection, haulage, and end-of-pipe issues, but must investigate issues such as waste minimization, in particular management of plastic waste which is a significant problem globally. Details are provided on information, education, and communication plans which are essential in supporting the physical interventions proposed in any plan for upgrading solid waste management services. Finally, all solid waste management plans must be regularly reviewed and information is provided on appropriate evaluation and diagnostic tools.

(ii)Waste categories. There are four different categories of waste that may or may not be accepted at a municipal solid waste facility such as a controlled landfill. The categories and typical components are described in this section, noting the always acceptable and prohibited items commonly found in the municipal context. Separate practice briefs deal with difficult wastes and special wastes likely to be encountered. These latter categories also include liquid waste, which may or may not be acceptable under some circumstances, as well as other materials such as asbestos and medical waste. Proper control of these types of waste is critical at any waste management facility.

(iii)Waste containers and collection. The practice briefs in this chapter is provided to guide municipalities in selecting the standard of service appropriate for their location, which leads to decisions on waste container types. These decisions relate to the appropriate collection fleet mix for providing the correct balance between controlling cost, minimizing public nuisance, and maximizing efficiencies. Because of the interrelation between these many components, all issues are contained in one practice brief rather than separating out the levels of service, container types, and haulage vehicle fleet decisions.

(iv)Waste processing and diversion. These briefs pertain to essential waste management interventions between the collection and disposal of residuals. Recycling is discussed in detail, together with pragmatic recommendations on the appropriate roles of government versus private sector and the most likely materials for economic recycling. Composting is usually a key issue for municipalities and the three-scale options are presented. Included also are some real-world examples of experience with the sustainability of large centralized facilities. Waste-to-energy approaches are attracting increasing levels of interest from a range of municipality sizes. Practice briefs are provided on treatment requirements before waste-to-energy is possible as well as the options for managing the emissions, which are often a concern to the community and civil society. Refuse-derived fuels and mass burn waste-to-energy facilities are also discussed.

(v)Landfill development. Even with significant effort directed toward waste avoidance, minimization, recycling, reprocessing, and diversion, there will always be residual requiring disposal. Practice briefs are provided on siting landfills and geotechnical assessments that may be required. Guidance is likewise provided on selecting an appropriate standard for the waste disposal facility based on contemporary pragmatic solutions that offer much greater sustainability than the previously supported best available treatment (highest technology) option. Other practice briefs provide details on a suitable approach to landfill sizing and key design elements for a controlled landfill, including inputs on appropriate landfill lining systems. More details are given on contemporary management approaches for landfill leachate, which is usually the main environmental concern at substandard facilities. This is further expanded upon in the specific brief on leachate collection and leachate lagoon systems.

(vi)Landfill operations. Ten practice briefs are provided in this chapter. This is because most landfills fail due to poor operation rather than poor design. Improved operations do not necessarily require a massive increase in budget, just an understanding of the required operational targets and the correct approaches. Practice briefs are presented on the key issues of stormwater runoff management and landfill gas control options. Guidance is also provided on how to lay out and stage landfill cells, as well as an overall operational overview for running a landfill. Critical elements such as waste compaction, litter management, and fire and pest control are also presented. The option of having waste pickers or scavengers on a controlled landfill is also presented, together with some appropriate management interventions. Guidance is provided on appropriate landfill reporting and complaints registers, again with links to a sample landfill operations manual as a resource document. Guidance on the development and implementation of a suitable environmental monitoring and management plan is also presented. The contemporary approach to remediating open and uncontrolled dumping is discussed, focusing on maximizing the life of old disposal sites rather than simply abandoning them, as well as minimizing environmental impact in parallel.

(vii)Contract issues. A key focus of the overall study was to support private sector involvement in appropriate phases of solid waste management. Experience gained from undertaking this study as well as general experience is presented in practice briefs dealing, for example, with packaging options for privatization. Some possible implementation issues with public–private partnerships are presented, as well as background details to contractual obligations of such partnerships. The major issue of contingent liabilities associated with termination fees and the impact on municipal finance planning are also presented. Information can be found on public–private partnership packaging issues where there are potential internal conflicts between contractors and shareholders leading to potentially substandard partnership outcomes.

SOLID WASTE MANAGEMENT PLANNING

Types of Municipal Solid Waste Characterization Audits

Issue

All aspects of solid waste management (SWM) planning are predicated on sound knowledge of the waste components and quantity that need to be managed. Many municipalities have access to previous waste characterization audits. However, in many cases, the data are very poor and cannot provide the integrity essential to good planning.

Therefore, audits are undertaken to verify the quality of the information available and to provide robust data in the absence of suitable waste characterization datasets.

These audits are also an opportunity to determine if prohibited waste is currently entering the disposal facility and take appropriate remedial action as required.

Interventions

There are two different approaches to waste characterization audits, as described below:

Characterizing individual waste streams followed by aggregating data

The first option is to have the collection trucks alter their usual collection route and have each vehicle collect from only one waste source, such as domestic waste or just commercial waste. Alternatively, waste can be hand-collected from a small number of households or other specific waste generators over a defined period.

A number of distinct and separate audits will then be conducted on the various waste streams. These individual audits will characterize each type of waste selected in the municipality, but not the combined waste stream.

Disaggregated data can be collected for a specific purpose, such as investigating composting organic waste from wet markets or commercial waste for refuse-derived fuel. Another use for domestic sampling is to check the effectiveness of any education campaigns regarding separating recycling products from domestic waste. The results can be used to amend education campaigns and delivery methods to best effect.

Separating mixed waste into categories.

To determine the combined waste stream characteristics overall, the results of the individual waste type audits have to be combined. Combining the results of the individual waste audits must be done using the actual ratio of the individual waste stream components based on long-term monitoring of the mass contributions from the various ways sources.

Collection vehicles typically carry mixed waste and there is no simple but accurate method of determining the exact mass contribution of each individual waste type. If there are no long-term and very accurate specific weight data available, aggregating the individual waste stream data to give an overall waste stream characterization will result in major