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This Glossary is focused on municipal solid waste management planning in low- and middle-income countries. It was prepared as an Appendix in the Environmental Resources Management's Strategic Planning Guide for Municipal Solid Waste Management (pdf), September 2000.

It has been prepared by extracting from several existing glossaries and dictionaries. A number of more detailed terms have been removed, while others more specific to the topic of the
 Planning Guide have been added. We have defined terms in the way we understand them and use them in this context, so that some terms may be defined differently from conventional usage as a consequence.


  • D. French (1985). Dictionary of Accounting Terms. Published by Croner Publications Ltd, Croner House, London Rd, Kingston upon Thames, Surrey KT2 6SR, UK. ISBN 1-85524-045-9.

  • US EPA (1989). Decision-Makers Guide to Solid Waste Management. Report No. EPA/530-SW-89-072, Office of Solid Waste and Emergency Response, US Environmental Protection Agency.

  • G. Bannock, R.E. Baxter & E. Davis (1992). The Dictionary of Economics. Fifth Edition. Published by Penguin Group, Penguin Books Ltd, 27 Wrights Lane, London W8 5TZ, UK.

  • US EPA (1992).Terms of Environment - Glossary, Abbreviations And Acronyms. Report EPA 175-B-92-001. Communications Education and Public Affairs, US Environmental Protection Agency.

  • J. Skitt, Editor (1992). 1000 Terms in Solid Waste Management. International Solid Waste Association, Copenhagen. ISBN 87-7751-056-9.

  • US EPA (1992). Decision-Makers Guide to Solid Waste Management. Report No. 530-R-95-023, Second Edition, Office of Solid Waste and Emergency Response, US Environmental Protection Agency.

  • UNEP (1996). International Source Book on Environmentally Sound Technologies for Municipal Solid Waste Management. United Nations Environmental Programme, Industry and Environment, Technical Publication Series 6.

  • A. Lagerkvist, Editor (1997). Landfill Dictionary. The Landfill Gas Activity of the International Energy Agency's Bioenergy Agreement & The ISWA Working Group on Sanitary Landfill. International Solid Waste Association, Copenhagen. ISBN 87-90402-03-0.

Glossary of Municipal Solid Waste Management Terms

. A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | XYZ


Accounting: 1.Accounting is concerned with the quantification of economic events in money terms in order to collect, record, evaluate and communicate the results of past events and to aid in decision-making. 2. The art of collecting, processing, reporting, analysing, interpreting and projecting financial information.

Accountability: Refers to the basic principle that the manager responsible for a service such as MSWM should have the authority to control all of the necessary functions of the organisation, and in return should take both responsibility and accountability for discharging the roles of the organisation in a cost effective manner.

Action Plan: The action plan sets out a detailed programme of implementation steps over a 5 year time frame, within the framework of the overall strategy for the long term. The Action Plan details who needs to do what, by when, how much it will cost and who pays.

Activated Sludge: The product that results when primary municipal wastewater (sewage) effluent is mixed with bacteria-laden sludge and then agitated and aerated to promote biological treatment, speeding the breakdown of organic matter in raw municipal wastewater undergoing secondary wastewater treatment.

Active Extraction Systems: The controlled withdrawal of gas (or leachate) from a landfill, usually pumping from a system of wells.

Active Landfills: Those landfills still accepting MS waste.

Acute Toxicity: Toxic effects which can cause rapid (acute) deleterious effects on biological (human, animal, plant) systems.

Aeration: The process of exposing bulk material, like compost, to air. Forced aeration refers to the use of blowers in compost piles.

Aerobic: Living systems or processes that require, or are not destroyed by, the presence of oxygen. (See: anaerobic).

Aerobic Decomposition: The first of the typical decomposition phases that occur in landfilled wastes. Refers to decomposition that takes place in the presence of oxygen. Carbon dioxide (CO2) is generated and oxygen is consumed.

Aerobic Treatment: The process by which microbes decompose complex organic compounds in the presence of oxygen and use the liberated energy for reproduction and growth (such processes include composting, secondary wastewater treatment, extended aeration, trickling filtration, and rotating biological contractors).

Affordability: Ability of the community to pay for the MSWM services as proposed.

Agricultural Waste: Farming wastes, including runoff and leaching of pesticides and fertilisers; erosion and dust from ploughing; improper disposal of animal manure and carcasses; crop residues, and debris.

Air Classification: A physical process in which a stream of air is used to separate municipal solid waste according to the size, density, and aerodynamic drag of the pieces.

Air Injection System: An air barrier is formed by utilising a series of vertical wells of trench barriers to inject air into virgin soil usually adjoining the landfill. Such systems are used to protect areas near a landfill from receiving migrating landfill gas.

Alternative Solution: see Option.

Alternative Strategies: A set of feasible strategies for MSWM in the long-term, differing in the options selected for key operating sub-systems or organisational aspects.

Anaerobic: A living system or process that occurs in or is not destroyed by the absence of oxygen.

Anaerobic Decomposition: The second phase of decomposition that typically occurs in landfilled wastes. Refers to decomposition in the absence of oxygen with (when complete) results in the formation of mainly methane (CH4) and carbon dioxide (CO2) gases.

Aquifer: A geological formation, group of formations, or portion of a formation capable of yielding significant quantities of groundwater to springs or wells.

Ash: Inorganic, particulate residue of combustion. Ash is usually polluted by small quantities of organic material resulting from incomplete combustion.

Audit: A systematic check of relevant aspects of an operation. Audits may include energy, waste, or a full audit of all matters that influence environmental performance.

Autonomy: An organisation has autonomy if it has the authority and responsibility for all six organisational functions required to function effectively. Improving autonomy enhances accountability and responsibility for poor performance.

Average Incremental Cost (AIC): This is a powerful method by which it is possible to establish the average unit cost of a service. AIC is calculated by dividing the present value of the cost stream by the present value of the waste stream. It represents a measure which can be used both for comparing project costs and for providing a good general indication of the affordability of the proposed measures. It provides a soun d basis for establishing the average tariff level needed to achieve full cost recovery from users.

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Back blading: A levelling technique in which the cutting edge of a tractor-driven earth-mover blade is drawn backwards over waste or cover material.

Backfill: The material used for, or the act of, refilling an excavation.

Bacteria: (Singular: bacterium): Microscopic living organisms that can aid in pollution control by metabolising organic matter in municipal wastewater (sewage), oil spills or other pollutants. However bacteria in soil, waterbody or air can also cause human, animal and plant health problems.

Baling: Compacting municipal solid waste or plastic and metal recyclables into blocks (called bales) to reduce volume and facilitate handling.

Ballistic Separator: A machine that sorts organic from inorganic matter for composting.

Bearing Capacity: The maximum load per unit area which the surface of a landfill can support without damage.

Best Practice: The planning and/or operational practice that is the most technically and politically feasible, cost-effective, sustainable, environmentally beneficial and socially sensitive, to a particular locality.

Bio-accumulation: The retaining and accumulation over time of certain chemical compounds in organic matter such as the tissues of plants and animals used as food sources.

Biodegradable: Capable of decomposing rapidly by microorganisms under natural conditions (aerobic and/or anaerobic). Most organic materials, such as food scraps and paper are biodegradable.

Biogas: Gas formed by digestion of organic materials. Typically dominated by CH4 and CO2 in a landfill.

Biological Treatment: A treatment technology that uses bacteria to consume organic fraction of municipal solid waste/wastewater.

BOD (Biochemical Oxygen Demand): Indicator of waterbody contamination that analyses the rate at which oxygen is consumed. The higher the number, the more contamination there is in the water. Expressed in milligrammes per litre.

Borehole: A hole drilled in the ground or landfill in order to obtain samples of the geological strata, wastes or liquids. Also used as a means of venting or withdrawing gas from landfills.

Bottom Ash: 1. The non-airborne combustion residue from burning solid fuel including MSW in boiler or incinerator; 2. The material which falls to the bottom of the boiler and is removed mechanically; 3. A concentration of the non-combustible rnaterials, which may include toxic substances.

Bring System: Collective term for methods of household waste separation at the point of generation involving the consumer taking separated materials to recycling centres (e.g., to take bottle to bottle banks).

Budget: Annual estimate of revenue and expenditure of an organisation (e.g., city/enterprise).

Build, Own, Operate (BOO): See Concession Contract.

Build, Own, Transfer (BOT): See Concession Contract.

Bulk Density: The density of a material (e.g., MSW) expressed as the ratio of mass to volume, including voids.

Bulky Waste: Large items of municipal solid waste including but not limited to appliances, furniture, large auto parts, tree stumps etc., which cannot be handled by normal municipal solid waste management methods.

Bund: An embankment usually of clay or other inert material used to prevent the lateral movement of wastes.

By-laws: Refers to subordinate municipal legislation, applicable and enforceable only within the legal borders or municipality. By-laws or municipal ordinances cannot e contradictory to national legislation.

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Calorific Value: The quantity of heat generated when unit mass of a material undergoes complete combustion under certain specified conditions. It is expressed in terms of kilo Joules (kJ) per kilogramme for solid or liquid fuels and kilo Joules per cubic metre for gases (kJ/m3). Gross (or 'higher') calorific value includes the enthalpy of vaporisation; net (or 'lower') calorific value excludes it.

Cap: A layer of clay, or other impermeable material installed over the top of a closed municipal solid waste landfill to prevent entry of rainwater and minimise leachate.

Capacity Building: Improving and building the technical and managerial skills and resources within an organisation.

Capital cost: Investment cost. Includes items such as land, site development, infrastructure, plant and equipment and licence costs.

Carbon Dioxide (CO2): A colourless, odourless, non-poisonous heavier than air gas; one of the major constituents of landfill gas. It is a by-product of aerobic and anaerobic decomposition. It decreases pH of water and is the most important greenhouse gas.

Cells: 1. A volume within a landfill occupied by a specific amount of waste, e.g., waste disposed during one day. The cell boundaries are then defined by a daily cover. A series of adjoining cells, all the same heights , make up a lift. 2. A compartment within a landfill designed for a particular purpose, for example the treatment of organic wastes. The cell has defined boundaries which may be a low permeability base, a bund wall and low permeability cover.

Centralised Composting: System utilising a central facility within a defined area with purpose of composting the putrescible fraction of MSW.

Chemical Treatment: Any one of a variety of technologies that use chemicals or a variety of chemical processes to treat municipal solid waste.

City Proper: The principal political jurisdiction containing the historical city centre.

Client Function: Refers to distinct roles inherent to MSWM services. `Client function' is the municipal responsibility for ensuring the provision of an adequate level of service, which protects public health and the environment, at an affordable cost, to all of the population.

Closure: The procedure a landfill operator must follow when a landfill reaches its legal capacity for municipal solid waste disposal which includes ceasing acceptance of municipal solid waste and placing a cap on the landfill site.

Co-disposal: The disposal of different types wastes in one area of a landfill. For instance, municipal wastewater (sewage) sludge may be disposed with regular municipal solid wastes. Co-disposal often involves mixing of solid and liquid wastes.

Collection: The process of picking up wastes from residences, businesses, or a collection point, loading them into a vehicle, and transporting them to a processing site, transfer station or landfill.

Collection/Disposal Interface: The interface between collection and disposal is usually defined when the secondary collection vehicle discharges its load of waste. Thus the transfer station and the bulk transport of waste from the transfer station to the treatment and disposal facility logically come within the responsibility of the authority responsible for treatment and disposal.

Collection Frequency: The number of MSW collections made from a specific location within a given time period.

Collection Timing: The pre-determined time period when MSW is collected from a location or pick-up point.

Collection Vehicle: Vehicle used to transport MSW collected from premises and streets to transfer stations and waste disposal site.

Combustion: Refers to controlled burning of municipal solid waste, in which heat chemically alters organic compounds, converting into stable inorganics such as carbon dioxide and water.

Commercial Waste: All municipal solid waste emanating from business establishments such as stores, markets, office buildings, restaurants, shopping centres, and entertainment centres.

Commingled Recyclables: Mixed recyclables that are collected together.

Comminution: Mechanical shredding or pulverising of waste. Used in both municipal solid waste management and wastewater treatment.

Community-Based Organisation: Community based interest groups formed by the members of a local community to take charge of their interests or to influence events.

Communal Collection: A system of collection in which individuals bring their MSW directly to a central point, from which it is collected.

Community Composting: System at a community level within a defined area with purpose of composting the putrescible fraction of MSW.

Compaction: Reduction of the bulk of municipal solid waste and increasing its density through a physical process such as rolling or tamping or as a result of waste compacting under its own weight.

Compaction Station: A type of transfer station in which MSW is compacted as an intermediate step before sending it to a disposal site.

Compost: The relatively stable humus material that is produced from a composting process of putrescible fraction of MSW in which bacteria in soil mixed with it break down the mixture into organic fertiliser.

Composting: 1. The controlled biological decomposition of putrescible fraction of MSW in the presence of air to form a humus-like material. Controlled methods of composting include mechanical mixing and aerating, ventilating the materials by dropping them through a vertical series of aerated chambers, or placing the compost in piles out in the open air and mixing it or turning it periodically (windrow composting). 2.The controlled degradation of putrescible fraction of MSW following some form of pre-processing to remove non-compostible MSW.

Concession Contract: Refers to a concession awarded by Municipality to a private company, via competitive tendering, to design, build, and operate (DBO) a facility for MSW treatment and disposal. Variations include build, own and operate (BOO) when the finance is provided by the private sector company and build, own and tran sfer (BOT) when the ownership transfers at an agreed data to the Municipality. In all cases the contracts provide for the Municipality to pay a gate-fee for each tonne of waste delivered.

Conservation: Preserving and renewing, when possible, human and natural resources. The use, protection, and improvement of natural resources according to principles that will assure their highest economic or social benefits.

Construction and Demolition Waste: MSW originated from or use of building materials, dredging materials, tree stumps, and rubble resulting from construction, re-modelling, repair, and demolition of homes, commercial buildings and other structures and pavements. The nature of this MSW depends upon the resources used in a given region or country for the purposes of construction. In the absence of adequate local ordinance, responsibility for the management of these wastes is invariably assumed to lie with the municipality.

Container: see Storage Containers.

Contaminant: Any physical, chemical, biological, or radiological substance or matter that has an adverse affect on air, water, or soil.

Contracting: An activity through which a competitive tender is awarded by municipality to a private firm to provide defined aspects of the overall MSWM service, for a fixed period. The contract may be for operation of a facility or vehicle fleet provided by the municipality, or it may require vehicle provision by the contractor (see also concession contract).

Corrugated Paper: Paper or cardboard manufactured in a series of wrinkles or folds, or into alternating ridges and grooves.

Cost-Effective Alternative: An alternative control or corrective method identified after analysis as being the best available in terms of reliability, performance, and cost.

Cost Effectiveness Analysis (CEA): Involves the identification and consistent evaluation of all costs, allowance for their phasing over time, and the application of decision criteria to rank and select between project options. The most appropriate criterion is the AIC (see Average Incremental Cost).

Cost Recovery: Recovering the cost of MSWM or other municipal services from the users. Cost recovery may be by direct or indirect charges.

Covering: Spreading of a layer of other material on the top of the masses of waste in order to reduce undesired impacts on the environment. Daily covering is used to cover each lift or layer at the end of each working day to limit odours, windblown litter, insect or rodent infestation, and water ingress.

Cover Material: Material used to cover municipal solid wastes disposed in landfills. Covering materials can be gravel, topsoil, excavation residues, or slag. Daily cover for a landfill might be important to reduce odours, nuisance, vectors, fires, landfill gas migration, and vegetation growth. Fifteen centimetres of compacted soil cover will generally achieve these desired functions. Soil texture determines the suitability of that soil for use as cover. Some areas allow the use of 'artificial cover' in lieu of compacted dirt. Examples are foam, geotextiles and plastic sheets.

Criterion/Criteria: Principle or standard that an alternative (opinion/strategy) is judged by.

Cullet: Clean, generally colour-sorted, crushed glass used to make new glass products

Curb-side Collection: Method of collecting recyclable materials at homes, community districts or businesses.

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Daily Cover: Daily cover for landfill is typically 15 cm layer of soil compacted over the waste. It might be important to reduce odours, nuisance, vectors, fires, landfill gas migration, and unsightliness of the facility and to promote safety and vegetation growth. Soil texture determines the suitability of that soil for use as cover. Some times 'artificial cover' may be used in lieu of compacted dirt, such as foam, geotextiles and plastic sheets.

Debt Coverage Ratio (DCR) is a measure of the financial viability of a MSWM strategy. It shows the ability of the income stream remaining after direct operating expenditures to meet debt service obligations.

Decomposition: The breakdown of matter by bacteria and fungi changing the chemical makeup and physical appearance of MSW in landfills, composting and/or fermentation processes.

Demand-sdte Waste Management: System whereby consumers use purchasing decisions to communicate to product manufacturers that they prefer environmentally sound products packaged with the least amount of waste, made from recycled or recyclable materials, and containing no hazardous substances.

Densified Refuse-Derived Fuel: A refuse-derived fuel (RDF) that has been processed through compaction to produce briquettes, pellets, or cubes.

Depreciation: Depreciation provisions are 'costs' and not 'expenditures' of an investment. They do not involve cash outlays but are a measure of the annual value (or cost) of physical assets used up in the provision of the service. They must therefore be taken into account when assessing the full annual costs of providing the service. This is one of the principal differences between the largely cash-based accounting systems sometimes used and the accruals based accounting system.

Design, Build, Operate (DBO) Contract: see Concession Contract

Digestion: The biochemical decomposition of organic matter of MSW, resulting in its partial gasification, liquefaction, and mineralisation.

Direct charges: The user of the service is charged for the use of the service, related directly to the extent of use. For MSWM, used widely for commercial and industrial wastes, less so for household wastes. See also Indirect Charges.

Discounted Cash Flow (DCF): It is a fundamental tool which allows the different cost streams of alternative strategies to be compared on a common basis. This involves discounting future cash flows to express them as their equivalent present values, thereby making them comparable. Average costs per tonne (AIC) are calculated by dividing the present value of the cash flows by the present value of the relevant waste stream.

Discount Rate: Used in discounted cash flow (DCF) analysis. It reflects the time value of money. The further into the future a cost is incurred the more its present value is reduced for a given discount rate. The discount rate expresses the 'cost' to the economy as a whole of using scarce resources in the proposed project rather than in some other activity. It is therefore sometimes referred to as the 'opportunity cost of capital'.

Disposables: Consumer products, other items, and packaging used once or a few times and discarded.

Disposal: 1. The final placement of MSW that is not salvaged or recycled. 2. The process of finally disposing MSW in a landfill. 3 MSW disposal is an ultimate action by which MSW is disposed on land in acceptable engineering manner with and/or without previous treatment/processing and/or recycling.

Diversion Rate: The percentage of waste materials diverted from traditional disposal such as landfilling or incineration to be recycled, composted, or re-used.

Domestic Waste: See Household Waste.

Donor Agency: An international or national (bilateral) development agency.

Double Composite Liner: A landfill liner system that uses synthetic and natural soil liners to prevent groundwater contamination. Two liners of each type are used, and each liner has several layers.

Double-Liner System: A system in which two liners are used in a landfill to protect against groundwater contamination. The liners may be either synthetic or natural, and may each be composed of several layers.

Dozer, Bulldozer, Crawler: Earth-moving machines fitted with continuous tracks and scraper blades. Designed for pushing or excavating; not for lifting.

Drop-off: Recyclable materials collection method in which individuals bring them to a designated collection site.

Drop-off Centre: A method of collecting recyclables or compost in which the materials are taken by individuals to collection sites and disposed into designated containers.

Drum: A container or a barrel usually mild steel or plastic, in which waste is stored.

Dump: A site used to dispose of municipal solid waste without management and/or environmental controls.

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Earthworks: Engineering work associated with the movement of soils.

Ecological Waste Management: An integrated approach to improving waste disposal in low-income countries in the short to medium term. Combines the phasing out of dumping and its replacement by controlled landfill with demonstration of appropriate recycling, composting and other treatment systems, with the intention that over time, an increasing percentage of MSW will be directed to disposal.

Economic evaluation: The principal means of determining whether a proposed investment is justifiable and for selecting between project alternatives. It concerns the investment decision rather than the financing decision. It is concerned with satisfying the investment criteria which commonly are set by the central government authorities in developing countries as well as those which may be set by international financing agencies.

Economies of Scale: Reductions in the unit cost of the production of a commodity or delivery of a service resulting from production/delivery on an increasing scale.

Effectiveness: The effectiveness of a service means the extent to which the objective of the service have been me in practice. For example, a street sweeping service is effective if the streets are clean.

Efficiency: A service is efficient if the available resources are used in the best possible way.

Effluent: The fluid discharged to the external environment.

Emission: A material which is expelled or released to the environment. Usually applied to gaseous or odorous releases to atmosphere.

End-Use Market: A company that purchases recycled materials for use as feedstock in manufacturing new products.

Energy Recovery: Obtaining energy from MSW through a variety of processes (eg combustion.)

Environment: The sum of all external conditions affecting the life, development and survival of an organism.

Environmental Audit: An independent assessment of the current status of a party's compliance with applicable environmental requirements or of a party's environmental compliance policies, practices and controls.

Environmental Impact Assessment (EIA): An environmental analysis prepared to determine whether an action (such as a proposed development project) would significantly affect the environment and the mitigation measures to reduce the impacts to acceptable level.

Environmental Monitoring: (of landfills). A continuous or regular periodic check to determine the environmental impact of landfill operations to ensure compliance with disposal licence conditions and other statutory environmental safety requirements.

Erosion: The wearing away and removal of weathered land surfaces by natural agents such as rain, running water, wind, temperature changes and bacteria.

Evaluation: Systematic assessment and/or comparison of available options/alternatives.

External Support Agency (ESA): see Donor Agency.

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Feasibility Study: 1.Analysis of the practicability of a proposal. The feasibility study usually recommends selection of a cost-effective alternative. 2. A small-scale investigation of a problem to ascertain whether a proposed research approach is likely to provide useful data.

Fermentation: Chemical reactions carried out by living microbes that are supplied with nutrients in the presence of heat, pressure, and light. The result of these reaction is usually methane, carbon dioxide and water.

Ferrous Metals: A term used to describe iron and its alloys, e.g., steels. It is also to describe the general class of metallic materials containing iron, cobalt and nickel as major components.

Filtration: Separation from a fluid of suspended particles or flocks.

Final Cover: Also known as secondary cover. The purpose is to make the landfill area suitable for the intended after use. Must be compacted (except the top soil), uniformly applied, and sloped to drain. Final cover must be designed to reduce infiltration, encourage run-off, while discouraging erosion, retain moisture for plant root growth and development, and reduce or enhance landfill gas migration. Depth and design requirements differ.

Financial evaluation: Evaluation whichconcerns the financing decision. Its purpose is to establish the sources and adequacy of funds necessary to meet the financial commitments incurred during both the implementation and operating stages of the investment.

Flood Plain: A region of low-lying land around a body of water, usually a river, that is flooded on an annual basis, usually annually.

Fluidised Bed Incinerator: An incinerator that uses a bed of hot sand or other granular material to transfer heat directly to waste. Commonly used for destroying municipal sludge generated at the municipal wastewater treatment facilities.

Fly Ash: Non-combustible residual particles of MSW expelled by flue gas.

Formal Source Separation: A process of municipal solid waste separation (eg paper, glass, metals, etc) in different containers carried out by a citizen. Containers are located at MSW generation sources (e.g. market places and shops, clusters of residential houses, etc.). The process is usually organised by the municipality in order to reduce the quantity of MSW requiring final disposal in landfill, and to encourage reuse, recycling and recovery of secondary raw materials.

Franchise: In the MSWM terms, it refers to the action by Municipality in which it awards, via competitive tendering, a limited monopoly to a private company to deliver a particular MSWM service, in a defined area for a fixed period. Generally the private company provides a performance bond to the municipality and pays a license fee to cover costs of monitoring service provision.

Functional Elements of MSWM System: The component parts of the technical and operational system for MSWM. Functional elements include: waste storage, primary collection, secondary collection, transfer, street sweeping and associated cleansing services, vehicle maintenance, material recovery and recycling, treatment and disposal (see also Operating Sub-Systems).

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Garbage: An American term for municipal solid waste arisings which include the putrescible fraction of MSW such as animal and vegetable waste resulting from the handling, storage, sale, preparation, cooking, and serving of foods.

Gas Control and Recovery System: A series of vertical wells or horizontal trenches containing permeable materials and perforated piping. The systems are designed to collect landfill gases for treatment or for use as an energy source.

Gas Migration: Is the movement of gas, either above or underground, from one area to another e.g., from within a landfill to the outside of the boundaries of the fill area. Gas is driven by two primary mechanisms, pressure and diffusion. Landfill gas exits from a landfill by vertical migration, lateral migration and migration along paths of least resistanc e until openings permit the release to the atmosphere. Landfill gas is heavier than air and therefore it can settle in low spots including sewers, basements, meter boxes, etc., and cause explosion and fires.

Gate Fee: Charge made by a MSWM facility operator for each tonne of waste delivered to the facility.

Generation: 1. MSW generation is a process of creating heterogeneous mixture of materials which are considered to be of no further use to the MSW generator. MSW is usually discarded from households, residential areas, commercial activities, educational establishments, hospital and clinics, business, shops, industries, etc. 2. Non-hazardous industrial waste, acceptable quantities of non-hazardous agricultural wastes, municipal wastewater (sewage) sludge and acceptable quantities of non-hazardous industrial sludges are also included in municipal solid waste generation.

Generation Rate: The amount of MSW that is generated over a given period of time. For example, a household of individual may have a MSW generation rate of 1kg/capita in a day.

Generator: Any person or organisation whose actions or process generate MSW.

Grinding: Breaking-up of e.g., waste to reduce the size of the pieces, by means of pressure, impact or shredding; the process is carried out in a specially constructed, closed device.

Ground Cover: Plants and vegetation grown to keep soil from eroding.

Groundwater. The supply of fresh water found beneath the Earth's surface, usually in aquifers, which supply wells and springs. Because groundwater is a major source of drinking water, there is growing concern over contamination from leaching pollutants out of dumping and/or badly managed landfill sites.

Groundwater Monitoring Well: A well placed at an appropriate location and depth for taking water samples to determine groundwater quality in the area surrounding a landfill or other site.

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Hammer-mill: A high-speed machine that uses hammers and cutters to crush, grind, chip, or shred MSW.

Handling, Collection and Transportation: The process of picking up MSW from residences, businesses, or a collection point, loading them into a vehicle, and transporting them to a processing site, transfer station or landfill.

Haul Distance: The distance over which wastes or landfill cover material must be transported either from a) the last pick-up point of the collection vehicles, or b) from the transfer station, to the landfill.

Hauler: 1. MSW collection company that offers complete service; 2. The term refers to collection of recyclables.

Hazardous Waste: Waste generated during production or other activities by society that can pose a substantial or potential hazard to human health or the environment when improperly managed. Possesses at least one of four characteristics (ignitability, corrosivity, reactivity, or toxicity).

Heavy Metals: Metallic elements with high atomic weights, e.g., mercury, chromium, cadmium, arsenic, and lead. It can damage living things at low concentrations and tend to accumulate in the food chain through build up of concentrations in plant and animal tissue.

Hierarchy: See Waste Management Hierarchy.

High-Density Polyethylene: A material used to make plastic bottles and other products that generated toxic gases and/or fumes when burned.

Household Waste (Domestic Waste): MSW composed of garbage and rubbish, which is generated as the consequence of household activities. In developing countries, up to two thirds of this category consists of putrescible fraction of MSW. In poor neighbourhoods traditional cooking can also produce ash and where sanitation facilities are limited, the waste might also include faecal matter. Domestic waste may contain a significant amount of hazardous waste.

Hydraulic Conductivity: A measurement of how fast a liquid can pass through the pores of a solid. Typically the liquid is water and the solid is a soil of some type.

Hydraulic Retention Time: The total liquid content of a volume (e.g., part of a landfill) divided by the rate at which liquid passes into, and out , of that volume.

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Ignitable: Capable of burning or causing a fire.

Immediate Action Plan: Identified as a sub-component of the overall action plan. It is defined as plan which requires relatively little time and money, is relatively uncontroversial and could be implemented within the first 12 months.

Immediate Improvements: Defined as a number of actions which could improve MSWM services in a city with little effort and at little or no cost. Aimed to be immediately implemented; does not require substantial investment; does not hinder the development of strategic plan; and effects can be measured in short period of time.

Impervious: Describes a material that does not allow another substance to penetrate or pass through.

Implementation: Strategic planning of MSWM is no t an end in itself, in that the entire exercise would be completely worthless without implementation and practice. The purpose of strategic planning is to provide a practical plan which is going to make a difference in practice when it is implemented. It is thus essential to ensure that there is a seamless transition from the planning process to implementation.

Inactive Landfill: 1. Landfills that have stopped accepting wastes. 2. Landfills where biological activity has ceased.

Incineration: 1. A treatment technology involving destruction of MSW by controlled burning at high temperatures, eg, burning sludge to reduce the remaining residues to a safe, non-combustible ash which can be disposed of safely on land. 2.The thermal process aimed in MSW destruction. It is applied in countries where high content of combustible fraction (paper and plastics/synthetics) is present in the MSW and where land for disposal is very limited and scarce. The main objective of this process is in reducing volume of MSW so that landfill life span could be extended. It requires high technological level in the country which is supported by adequate equipment, infrastructure facility and trained personnel.

Indirect Charges: Payment for a service (in this case MSWM) is linked either to the general municipal charge (e.g., property tax), or to another service for which charges are paid on the extent of use, and where the sanction of disconnection exists for non-payment (e.g., drinking water, sewage or electricity).

Industrial Waste: A heterogeneous mixture of different materials generated during an industrial operation. It may be gaseous, liquid, sludge, and/or solid. The composition is site specific and depends upon the natural resources, raw materials and markets which provide the base for a given city's industrial activity.

Inert: Lacking the ability to chemically react with other substances.

Inert Material: The term is commonly used to describe material which is unaffected by chemical and/or biological processes. Generally indicating that the presence of such material has no relevant influence on the process under study, e.g., glass does not contribute to methane formation and can be regarded as inert in that aspect.

Infectious Waste: Hazardous waste with infectious characteristics, including contaminated animal waste, human blood and blood products, isolation waste, pathological waste, and discarded sharps (needles, scalpels or broken medical instruments).

Informal Sector: The part of an economy that is characterised by private, usually small-scale, labour-intensive, largely unregulated, and unregistered manufacturing or provision of services. In MSWM it refers to recycling activities (see: waste picking, scavenging).

Information Management System (IMS): A system (usually computer supported) in which data/information is collected, stored, organised, processed, utilised and disseminated. The IMS is used for decision-making, planning, monitoring, problems solving and creation of new knowledge.

Institutional Aspects: Concerns the distribution of functions and responsibilities of MSWM (see also Organisational Aspects).

Institutional Strengthening: Process designed to enhance the ability of an institution to meet its objectives more effectively through a combination of measures including technical assistance, training, improved management structure system and better legislative and regulatory frameworks.

Institutional Waste: Waste originating in schools, hospitals, prisons, research organisations and other public buildings. Where the institution involves residents, the waste composition is similar to those from households.

Integrated Waste Management: 1. A frame of reference for designing and implementing new waste management systems and for analysing and optimising existing systems Based on the concept that all the strategic aspects of the MSWM system should be analysed together since they are interrelated and development in one component frequently affects other areas of the system. 2. A practise using several alternative waste management techniques to manage and dispose of specific components of the municipal solid waste stream. Waste management alternatives include source reduction, recycling, composting, energy recovery and landfilling.

International NGO: An organisation that has an international headquarters and branches in major world regions, often with the purpose of undertaking development assistance.

In-Vessel Composting: A composting method in which the compost is continuously and mechanically mixed and aerated in a large, contained area.

Itinerant Waste Buyer: A person who moves around the streets buying (or bartering for) reusable and clean recyclable waste materials.

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Karst: A geologic formation of irregular limestone deposits with sinks, under ground streams, and caverns.

Key Stakeholders: Those persons, groups or institutions who can significantly influence, or are important to the success of a project/programme.

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Lagoon: A containment area for leachate or municipal wastewater. Lagoons may be formed above or below ground in natural or artificially created depressions.

Landfill Farming: Using a topsoil for the mixing in and treating some wastes and/or sludges. The mainly biological process will result in useable material for plant growth.

Landfill Fire: Burning of waste on surface or deep inside a landfill. Surface fires can usually be put out easily. A deep fire within the covered section of a landfill is very difficult to put out and can burn for weeks or months.

Landfill Gas Management: The active and complete involvement in all issues of landfill gas, including: extraction, monitoring, disposal and reporting to regulators.

Landfill Gases: Gases arising from the decomposition of the organic (putrescible) fraction of MSW; principally methane, carbon dioxide, and hydrogen sulphide. Such gases may cause explosions at landfills if not properly managed.

Landfills: Designed, controlled and managed disposal sites for MSW spread in layers, compacted to the smallest practical volume, and covered by material applied at the end of each operating day (see also sanitary landfill).

Landraising: Also called area method of landfilling. The spreading of waste in horizontal layers. Used on flat or gently sloping land when no excavation is proposed.

Lateral Pipe: A pipe used to connect wells or trenches in a landfill.

Law: Generally used for primary national legislation, often at generic or 'enabling' level, requiring detailed regulations for its implementations.

Leachate: Wastewater that collects contaminants as it trickles through MSW disposed in a landfill. Leaching may result in hazardous substances entering surface water, ground water, or soil.

Leachate Collection System: A system that gathers leachate (usually in a landfill) and pumps it to the wastewater treatment facility.

Leachate Management: The active and complete involvement in all issues of landfill leachate, including: collection, monitoring, disposal and reporting to regulators.

Leachate Treatment: A process to reduce the pollution potential of leachate. Such processes can include leachate re-circulation, spray irrigation over adjacent grassland, and biological and physical-chemical processes.

Legal framework: The framework of law , usually comprising national laws and regulations and municipal by-laws.

Level of Service: This refers to the quantity and quality of the MSW collection service, the effectiveness of MSW handling, treatment and disposal operation.

License: see Permit.

Lift: The completed layer of compacted MSW in a cell at a landfill.

Liner: A relatively impermeable barrier designed to contain leachate within a landfill. Liner materials include plastic and dense clay.

Litter: Wind blown municipal solid wastes (predominantly plastics and paper) at a waste handling, treatment or landfill facility.

Long Range Transfer: Transport of municipal solid waste from the collection round to transfer station using conventional, powered refuse collection vehicles with high capacities, usually over distances of 20 km or more.

Low-income countries: In the context of this Planning Guide, low-income refers to cities in low-income and lower-middle income countries as defined by the World Bank. The term "low-income country" is used to replace the term "developing country". According to the World Bank Atlas classification system, low-income countries, are those with a GNP per capita of equal or less than $695 (in 1993 dollars). In comparison, Lower-middle income countries have GNP per capita between $696 - $2,785, Upper-middle income countries: $2,786 - $8,625, and High-income countries have a GNP per capita of equal to or more then $8,626.

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Macro-routing (or route balancing): Creating collection routes by dividing a collection area into smaller areas representing one day or work for one crew.

Magnetic Separation: Use of magnets to separate ferrous materials from mixed municipal solid waste stream.

Management Information System: see Information Management System.

Mandatory Recycling: Programs which by law require consumers to separate waste so that some or all recyclable materials are recovered for recycling rather than going to landfills for disposal.

Manual Separation: Hand separation of compostable or recyclable material from MSW.

Market: A market is created whenever potential sellers of a good or service are brought into contact with potential buyers. In MSW refers to a sustainable market for recovered materials and is essential to the success of recycling.

Market Wastes: Primarily putrescible MSW, such as leaves, skins, and unsold food, discarded at or near food markets.

Mass Burn System: A combustion technology in which municipal solid waste is burned in a controlled system without prior sorting or processing.

Materials Recovery Facility (MRF): Facility that processes residentially collected mixed recyclables into new products.

Mechanical Separation: Using mechanical means to separate MSW into various components.

Media: Specific environments-air, water, soil-which are the subject of regulatory concern and activities.

Medical Waste: Any municipal solid waste generated in the diagnosis, treatment, or immunisation of human beings or animals.

Methane: A colourless, non-poisonous, flammable gas (CH4) created by anaerobic decomposition of organic compounds. It is explosive and should be handled with care (see also "anaerobic decomposition", "biogas").

Methodology for MSWM Planning: A method applied to addressing a need or solving a problem in MSWM Planning. A methodology can be expressed in text form, as a flow-chart or any other structured form of presentation. In order for a methodology to be effective it must be coherent and self-contained.

Metropolitan Area: A politically defined urban area set up for planning or administrative purposes which may combine several jurisdictions (municipalities or cities).

Micro-enterprise: A synonym for small-scale enterprise: a business, often family-based or a co-operative, that usually employs fewer than ten people and may operate "informally".

Micro-organism: Living organisms so small that individually they can only be seen through a microscope.

Minimisation: A comprehensive program to minimise or eliminate wastes, usually applied to wastes at their point of generation. (See: waste minimisation.)

Mitigation: Measures taken to reduce adverse impacts on the environment.

Moisture Content: The fraction or percentage of a substance or soil that is water.

Monitoring: 1. Periodic or continuous surveillance or testing to determine the level of compliance with statutory requirements. 2. A process including physical examination, measurements by portable instruments and analysis of sample to provide information for assessment of conditions.

Multiple Manual Handling: Inefficient handling of MSW whereby the same load of waste has to be manually handled several times. For example, the waste may be dropped in the street to wait for a collection vehicle, reloaded by hand, unloaded onto the ground at the transfer station and reloaded by hand for transport to the disposal site (double manual handling, or four times if non-tipping vehicles are used which require unloading by hand). Single manual handling is the maximum in most industrialised countries.

Municipal Solid Waste (MSW): Includes non-hazardous waste generated in households, commercial and business establishments, institutions, and non-hazardous industrial process wastes, agricultural wastes and sewage sludge. In practice, specific definitions vary across jurisdictions.

MSW Composition: MSW is as a heterogeneous mixture of different types of discarded materials. The composition of MSW depends on the conditions of the city in question. In general, MSW is composed of the following fractions: paper, rubber, plastic, fabric, leather, vegetable/putrescible, wood, etc. (combustibles), coal ash, glass, metal, etc. (non-combustibles).

MSW Management (MSWM): Supervised municipal solid waste management from their source of generation through collection or street sweeping, recovery and/or treatment/ processes to disposal.

Municipal Wastewater (Sewage): The spent or used water from a home, community, institution, farm, or industry that contains dissolved or suspended matter (see wastewater).

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Natural Liner: A landfill liner that is made up of low-permeability soil.

NIMBY: Acronym for "Not In My Back Yard"; an expression of resident opposition to the siting of a municipal solid waste management facility based on the particular location proposed.

Night soil: Human excreta.

Nitrogenous Wastes: Animal or vegetable residues that contain significant amounts of nitrogen.

Non-Methane Organic Compounds: Usually totals less than 1% of landfill gas. The most commonly detected compounds are trichloroflouromethane, trichloroethylene, benzene, vinyl chloride, toluene, perchloroethylene, and methylene chloride, ethyl benzene, dichloroethylene, which are hazardous substances.

Non-Point Source: Diffuse pollution sources (i.e., without a single point of origin or not introduced into a receiving stream from a specific outlet). The pollutants are generally carried off the land by storm water. Common non-point sources are agriculture, forestry, urban, mining, construction, dams, channels, land disposal, saltwater intrusion, and city streets.

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Objectives: Referring or relating to a goal or aim of an action(s) (see also Targets).

Odour Control: The use of equipment such as activated carbon filters, odour- attenuating cover materials, and gas flaring to reduce or eliminate odorous gases emanating from decomposing wastes.

Open Burning: Uncontrolled fires in an dump.

Open Competition: Free competition between service providers. The Municipality generally compiles a register or issues licenses to companies considered competent to provide MSW collection, recycling or disposal services. These companies are then free to compete for contracts with individual householders and commercial establishments for MSW collection, recycling and/or disposal.

Open Dump: A site used for disposal of waste without any management and/or environmental controls (see also dump).

Operating cost: They are the day to day expenses of an operation. They include items such as labour, fuel, materials, chemicals, utilities, repairs and maintenance, and insurance.

Operating Sub-Systems of MSWM: The component parts of the technical and operational system for MSWM. Operating sub-systems include: waste storage, primary collection, secondary collection, transfer, street sweeping and associated cleansing services, vehicle maintenance, material recovery and recycling, treatment and disposal.

Operation: The process of waste handling and associated management activities.

Operational Planning for MSWM: Refers to the detailed tactical or operational planning level of MSWM, often associated with the implementation of the strategic plan. While the Action Plan might indicate, for example, the types and methods of collection to be adopted and the numbers and types of vehicles, operational planning would take this to the next level of detail, for example, including the routing of individual vehicles (See also Functional Elements of MSWM).

Operator Function: Refers to distinct roles inherent to MSWM services. Operator function is the day to day delivery of MSWM services (also known as the 'contractor function'). May be carried out by the public or by the private sector.

Option: Used here to denote an alternative solution for either operating sub-system or an operational aspect of the MSWM system. A set of preferred options, one for each component, comprises an alternative strategy.

Organic: 1. Referring to or derived from living organisms. 2. In chemistry, any compound containing carbon.

Organic Chemicals/Compounds: Animal or plant-produced substances containing mainly carbon, hydrogen, nitrogen, and oxygen.

Organic Matter: Carbonaceous material contained in plant or animal matter and originating from domestic or industrial sources.

Organisational Aspects: Refers to issues which need to be addressed when analysing institutional systems for MSWM. Includes: distribution of responsibility for operating sub-systems; inter-municipal co-operation; organisation with MSWM institutions; separation of the MSWM; strengthening management within an autonomous department to fulfil its functions and responsibilities; opportunities for private sector involvement.

Organisational Functions: Basic management theory identifies six organisational functions which must be carried out by corresponding organisational systems for any institutional organisation to function effectively. These are the following: planning, operations, commercial, financial, administrative support and monitoring.

Oxidation: The reaction with oxygen which breaks down organic waste or chemicals such as cyanides, phenols, and organic sulphur compounds in municipal wastewater (sewage) by bacterial and chemical means.

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Packaging: The assembly of one or more containers and any other components necessary to assure minimum compliance with a programme's storage and shipment packaging requirements. In industrial countries it represents the largest fraction of MSW.

Packaging Waste
: Material discarded after the product in the packaged materials has been removed for use. Such a waste is discarded by both residential, commercial and industrial sectors.

Participation Rate: A measure of the number of people participating in a recycling programme compared to the total number that could be participating.

Passive Venting: A venting technique using the natural pressure created in landfills to expel gases and control gas migration.

Pathogenic: Capable of causing disease.

Pathogens: Micro-organisms that can cause disease in other organisms or in humans, animals and plants (eg bacteria, viruses, or parasites) found in municipal solid waste, sewage, in runoff from farms or rural areas populated with domestic and wild animals, and in water used for swimming.

Percolate: To ooze or trickle through a permeable substance. Groundwater may percolate into the bottom of an unlined landfill.

Performance Indicators: Quantitative data related to service delivery, such as number of employees, length of streets or total t onnes of MS waste collected.

Performance Measures: The result of processing indicators, generally by relating them to either time or costs. Performance measures are the principal tool for performance monitoring. Examples include cost/tone of MSW disposed, length of streets swept /hour.

Performance Monitoring: Measuring the performance of a service on an on-going basis, in order to encourage the efficient use of available resources.

Permeability: A measure of how well a liquid moves through the pores of a solid. Expressed as a number applied to landfills in terms of how quickly water moves through compacted MSW disposed; it is typically expressed as centimetres per second.

Permeable: Having pores or openings that permit liquids or gasses to pass through.

Permit: An authorisation, license, or equivalent control document issued by governmental body or an approved state agency to implement the requirements of an environmental regulation; eg a permit to operate a landfill site or to operate a facility that may generate harmful emissions.

Pest: An insect, rodent, nematode, fungus, weed or other form of terrestrial or aquatic plant or animal life that is injurious to health or the environment.

Physical and Chemical Treatment: Processes generally used in large-scale waste-water treatment facilities. Physical processes may include air-stripping or filtration. Chemical treatment includes coagulation, chlorination, or ozonisation.

Pickers: see Waste Pickers

Picking: see Waste Picking

Pilot Programme: A trial run of the planned programme conducted on a small scale to forecast the workability of the planned programme. Changes may be made to the programme depending on the results of the pilot study.

Planning Area: Defined as the area to be considered within the strategic plan for MSWM. It should be large enough to provide for the siting of shared disposal facilities. At a minimum, the formal metropolitan area should be considered.

Planning Framework: Refers to the general framework within which strategic planning is conducted. Components include: selection of the planning area, and planning period; selection of the types of MSW to be covered by the plan; definition of the level of MSW collection and disposal services; and setting of objectives and targets for the plan.

Planning Period: Is defined as period of time considered by the Strategic Plan. The Strategy covers a planning period of 15 years, while Action Plan covers planning period up to 5 year.

Plastics: Non-metallic chemically reactive compounds (polymers) moulded into rigid or pliable construction materials, fabrics, etc. It represents considerable fraction of MSW in industrial countries.

Plume: A three dimensional envelope that contains all the material (solid, liquid or gas) released by a source into its surroundings.

Point Source: A stationary location or fixed facility from which pollutants are discharged; any single identifiable source of pollution.

Policy: A series of broad statements setting out the overall policy framework for either environmental management and/or MSWM at the national or regional level. For MSWM, policy is often termed a "national sector strategy".

Pollution: Generally, the presence of matter or energy whose nature, location, or quantity generates undesired environmental effects.

Pollution Prevention: The active process of identifying areas, processes, and activities which generate excessive waste for the purpose of substitution, alteration, or elimination of the process to prevent waste generation in the first place.

Porous: Containing holes or voids.

Post-Closure: The time period following the shutdown of a MSWM or manufacturing facility; for monitoring purposes, often considered to be 30 years (also used terms are after care and/or restoration).

Post-Consumer Materials: Materials that a consumer has finished using, which the consumer may sell, give away, or discarded as municipal solid wastes.

Post-Consumer Recycling: Reuse of materials generated from residential and consumer waste, eg converting wastepaper from offices into corrugated boxes or newsprint.

Present Value: The value now of a sum of money to be paid or received in the future.

Pre-treatment: Process used to reduce, eliminate, or alter the nature of wastewater pollutants from non-domestic sources before they are discharged into wastewater treatment facility.

Primary Collection System: The means by which municipal solid waste is collected from its source (domestic and commercial premises) and transported to communal stations, transfer points or disposal sites. Usually primary collection systems are characterised in developing countries by hand carts, bicycles or small vehicles.

Primary Stakeholders: Those p ersons, groups or institutions directly affected, either positively (beneficiaries) or negatively (for example, those involuntarily resettled) by a proposed action or plan.

Prime Costs: The direct capital and operating expenditures incurred over the planning period of an investment project. They do not include other associated cost such as interest payments or depreciation allowance.

Private Sector: The part of economy in which economic activity is carried out by private enterprise as distinct from the public sector.

Private Sector Participation: A partnership between the public and private sectors in MSWM, which allows the private sector to participate in service delivery. Term preferred in MSWM context to 'privatisation', which implies that the public sector is no longer responsible for ensuring provision of the service.

Problem Definition: In the context of strategic planning for MSWM, requires a diagnostic study to determine MSW quantities and composition, to review MSWM operations and to predict future capacity requirements. The output should be a clear definition of the current and future likely problems within the MSWM system, and the barriers, constraints and opportunities for improvement to be addressed in the strategic plan.

Producer Responsibility: In order to reduce generation of packaging and other commercial waste, many governments have introduced the legislation requiring certain type of 'producers' to minimise their packaging and/or accept back their own products which have no more value for consumers. In effect, the responsibility e.g., for packaging waste is transferred for the municipality to the 'producer'.

Public Awareness and Education: Public Awareness and Education campaigns can take many shapes and forms. Just a few examples are information leaflets, public hearings, radio programs, advertisements, lectures and school curriculum interventions.

Public Cleansing Services: A variety of services related to waste collection, which may include street sweeping, gully emptying, drain cleaning, night soil removal, septic tanks/cess pit emptying, beach and foreshore cleaning, snow and mud cleaning, grass cutting, waste backlog clearance, clean up after natural disasters, letter prevention, graffiti removal, cleaning of public toilets and/or other cleaning tasks.

Public Good: Refers to commodities or services whose benefits are not depleted by additional users and for which it is generally difficult, if not impossible, to exclude people from its benefits even if they are unwilling to pay for it. People that use public goods without paying for them are called 'free-riders'. MSWM exhibits these characteristics, and therefore it follows that MSWM services are a public goods which municipality has to maintain the overall responsibility of supplying.

Public Hearing: A formal meeting wherein governmental environmental officials hear the public's views and concerns about an action or proposal.

Putrescible: A fraction of MSW which can decompose under aerobic or anaerobic conditions, used as a feedstock for composting or anaerobic digestion processes.

Putrefaction: Spontaneous slow biodegradation under anaerobic conditions in which offensive-smelling compounds such as ammonia, hydrogen sulphide, etc., are formed.

Pyrolysis: Decomposition of an organic substance (by heating, in the absence of oxygen) to degrade solid wastes to oils and gas.

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Quality Assurance/Quality Control: A system of procedures, checks, audits, and corrective actions to ensure that all research design and performance, environmental monitoring and sampling, and other technical and reporting activities are of the highest achievable quality.

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Raw Sludge: Sludge which has been separated by treatment of wastewater or sewage, and which has not undergone further treatment or stabilisation.

Recipient: Medium into which residues are discarded, e.g., open sea, lake, watercourse or atmosphere.

Reclamation: Restoration of materials found in the MSW stream to a beneficial use which may be for purposes other than the original use (use in recycling).

Recovery: Chemical/biological processes such as biogas (methane) generation carrying out at the landfill to recover gas (energy/heat). Municipal wastewater sludge generated at the municipal wastewater treatment facility are usually added to enhance process of gas generation. Putrescible fraction of the MSW is also used to produce compost and/or methane by fermentation (anaerobic digestion). 2. The process by which MSW otherwise destined for disposal are collected, re-processed or re-manufactured, and reused.

Recovery Rate: Percentage of useable recycled materials that have been removed from the total amount of municipal solid waste generated in a specific area or by a specific business.

Recurrent Costs: The costs incurred in operating MSWM services. They can include: direct operational expenditures, such as expenditure on wages, fuel and maintenance; provisions (accrued expenses) for liabilities such as employee pension obligations and insurance payments; regular recurrent cash outlays, such as debt repayment and service charges (capital and interest); and a provision (depreciation) for recovering the value of the capital assets progressively used up in delivering the service.

Recyclables: MSW fractions that still have useful physical and/or chemical properties after serving their original purpose and that can therefore, be reused or re-manufactured into additional products.

Recycle/Reuse: Recovering and re-processing useable MSW that might otherwise end disposed in landfills (i.e. recycling of aluminium cans, paper, and bottles, etc.).

Recycling: Separation physical/mechanical process by which secondary raw materials (paper, metals, glass, plastics/synthetics) are obtained from MSW. The process could be accomplished manually, by simple and/or sophisticated mechanical equipment.

Refuse: Another term for municipal solid waste.

Refuse-Derived Fuels (RDF): Product of a mixed MSW processing system in which certain recyclable and not combustible materials are removed and the remaining combustible material is converted for use as a fuel to generate energy.

Refuse Reclamation: Conversion of municipal solid waste into useful products, eg composting to make soil conditioners or separating aluminium and other metals for recycling.

Regulation: Generally used for secondary national legislation; i.e. detailed regulations to implement a more general law.

Regulator Function: Refers to the responsibility for ensuring that MSWM happens in a manner which is in conformance with legal requirements. In practical terms, this largely relates to the prevention of illegal waste disposal (dumping) activities, inspecting and monitoring the operation of landfill sites and other waste management facilities to ensure the conditions of the site license or permit.

Remediation: Cleanup or other methods used to remove or contain a toxic spill or hazardous materials from a site.

Reserve Capacity: Extra treatment capacity built into municipal solid waste and wastewater treatment plants and interceptor sewers to accommodate flow increases due to future population growth.

Residential Waste: MSW generated in single and multiple-family homes.

Residual: Amount of a pollutant remaining in the environment after a natural or technological process has taken place, eg the sludge remaining after initial wastewater treatment, or particulates remaining in air after it passes through a scrubbing or other process.

Residuals: Unintended outputs of production processes. These include municipal solid waste and wastewater.

Residue: The materials remaining after processing, incineration, composting or recycling of MSW. Residues are usually disposed of in landfills.

Resource Recovery: The process of obtaining matter or energy from MSW.

Responsibility: see Accountability.

Restoration: Completion of a landfill site to allow planned after-use.

Reuse: Using a component of MSW in its original form more than once, eg refilling a glass bottle that has been returned or using a coffee can to hold nuts and bolts.

Revenue: Income, especially of large amount from any source.

Routing: The detailed assignment of MSW collection vehicles and labour to collection routes such that collection efficiency is optimised.

Rubbish: The US EPA defines rubbish as municipal solid waste, excluding food waste and ashes, from homes, institutions, and work-places.

Run-off: That part of precipitation, snow melt, or irrigation water that runs off the land into streams or other surface-water. It can carry pollutants from the air and land into receiving waterbody.

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Salvage: At landfills or material recovery facilities, salvaging is the controlled separation of recyclable and reusable materials. Controlled means that the separation is monitored by operators.

Sampling: Collecting a portion of a large amount as representative of the whole.

Sanitary Landfill: A US term for land MSW disposal site that is located to minimise water pollution from runoff and leaching. MSW is spread in thin layers, compacted, and covered with a fresh layer of soil each day to minimise pest, aesthetic, disease, air pollution, and water pollution problems (see also: landfill).

Sanitation Residues: These are human excreta residues collected from privies and latrines (often called 'night-soil') which, depending on the level of sewerage provided, may be dumped in street drains and therefore arise in drain clearing and street sweeping wastes.

Scavenging: (see waste picking, waste picker).

Scrap: Materials (principally metallic) discarded from manufacturing operations that may be suitable for reprocessing.

Screen: 1. A mesh, supported vertically, used to capture windblown waste. 2. A mesh used for separating pulverised or shredded wastes. 3. A mechanical device used to separate medium and larger size solid material from an effluent prior to further treatment.

Secondary Collection: The collection of municipal solid waste from communal collection points and/or generator premises and transport (often as part of a collection round) to a transfer station, recycling centre, intermediate treatment facilities or disposal site.

Secondary Leachate: When water percolates through a landfill, the water becomes contaminated and becomes leachate. This is also known as secondary leachate.

Secondary Raw Materials (SRM): 1. Materials that have been manufactured and used at least once and are to be used again. 2. Secondary materials (eg paper, glass, metals, etc) obtained from municipal solid waste by the processes of reuse, recycling and/or recovery carried out at the municipal solid waste treatment/process facilities.

Secondary Raw Materials Recovered from Disposal Sites (SDS): Material scavenged for re-use and recycling from MSW disposal sites (dumps, landfills).

Secondary Raw Materials Recovered from Point of Waste Generation (SPWG): Material recovered from temporary MSW storage locations.

Secondary Raw Materials Recovered from Street Bins (SSB): Material recovered from MSW bins and communal storage stations prior to its collection.

Secondary Raw Materials Recovered from Transfer Stations (STS): Material scavenged and recovered/recycled from MSW handled at the transfer station.

Secondary Raw Materials Recovered from Waste Collection Vehicles Prior to Transfer Station (SCV): Material scavenged from MSW collection vehicles.

Secondary Raw Materials Recovered from Waste Haulage Vehicles (SHV): Material scavenged or recovered from vehicles transporting MSW from collection sites and transfer stations to MSW disposal sites.

Secondary Stakeholders: The intermediaries in the project or programme delivery process.

Secondary Treatment The second step in most publicly owned municipal wastewater treatment systems in which bacteria consume the organic parts of the municipal wastewater. It is accomplished by bringing together wastewater, bacteria, and oxygen in trickling filters or in the activated sludge process. This treatment removes floating and settleable solids and about 90 percent of the oxygen-demanding substances and suspended solids. Disinfecting is the final stage of secondary treatment. (See: primary, tertiary treatment).

Sedimentation: Also settling. Separation of particles, sediment, from a liquid or a gas by means of gravitational force.

Sensitivity Analysis: Analysis of how errors in one or more estimates would affect the conclusion drawn from the estimates.

Separated Waste Collection, Transfer and/or Transport: The process of collecting and removing MSW which have been separated in order to facilitate their re-use, recycling, processing or disposal.

Separated Waste Temporary Storage: MSW separated by different fractions into differently marked containers prior to their separate collection and transport to recycling centres for further processing/treatment.

Seepage: See also "leachate".

Set-out Container: A box or bucket used for residential MSW that is placed outside of the dwelling for collection.

Sewage: see Municipal Wastewater.

Sewage Sludge: Sludge generated at the municipal wastewater treatment facility; it usually refers to secondary sludge settled after biological treatment is completed. Often accepted for disposal at the landfill.

Shadow Pricing: Governmental development policies can sometimes create distortions in market prices to such an extent that they bear little relationship to real economic costs. The adjustment of these market prices to reflect economic costs is known as shadow pricing.

Sharps: Hypodermic needles, syringes (with or without the attached needle) pasteur pipettes, scalpel blades, blood vials, needles with attached tubing, and culture dishes used in animal or human patient care or treatment, or in medical, research or industrial laboratories. Also included are other types of broken or unbroken glassware that were in contact with infectious agents, such as used slides and cover slips, and unused hypodermic and suture needles, syringes, and scalpel blades. If not separated these waste could find the way into MSW streams.

Short Range Transfer: Movement of MSW from storage to transfer station by means of hand or animal powered vehicle (or small powered vehicles) over short distances.

Shredder: A mechanical device used to break MSW materials into smaller pieces by tearing and impact action. Shredding MSW is done to minimise its volume or make it more readily combustible.

Single Manual Handling: The handling of waste between initial storage and final disposal so as to eliminate multiple manual handling (cross refer). It involves moving waste directly from on e container (or vehicle) to another, rather than emptying on the ground and manually reloading. Achieving single manual handling in waste collection is the most effective means of improving the system.

Site Specification: A reference list relating to a landfill site, prepared during the project planning stage, containing information on site details, method of working, equipment required, types of MSW and other relevant items.

Siting: The process of choosing a location for a MSW treatment/processing facility and/or landfill (site selection).

Sludge: A semi-solid residue from any of a number of air and/or water treatment processes.

Soil Conditioner (Soil Improver): An organic material like humus or compost that helps soil absorb water, build a bacterial community, and take up mineral nutrients.

Soil Liner: Landfill liner composed of compacted soil used for the containment of leachate.

Solid Waste: MSW composed of solid matter from household, commercial, institutional and industrial sources (see MSW).

Sophisticated MSWM System: This system of MSWM is aimed to avoid generation of MSW as the highest priority and/or to reduce MSW generation by introducing separation at the source. Separate collection system implies collection of separated waste by types. This is mostly done in industrialised countries where standard of living is high enough that municipal services could afford high standard of MSWM system.

Source Reduction: Reducing the amount of waste entering the MSW stream by redesigning products or patterns of production or consumption (eg using returnable beverage containers). Synonymous with waste reduction.

Source Separation: Segregating various wastes at the point of generation (eg separation of paper, metal and glass from other wastes to make recycling simpler and more efficient).

Stakeholders: Persons, groups or institutions with interests (often financial) in a project or programme (see Primary Stakeholders; Secondary Stakeholders).

Standards: Governmental norms that impose limits on the amount of pollutants or emissions generated.

Stationary Source: A fixed-site generator of pollution, mainly power plants and other facilities using industrial combustion processes.

Steering Committee: High-level committee to oversee in this case MSWM strategic planning process. The Steering Committee will assist the MSWM plan through a process of review, expert opinion and access to viewpoints that will help to establish a supported consensus.

Sterilisation: The destruction of all living organisms in water, on the surface of various materials or MSW. By contrast, disinfection is the destruction of most such organisms.

Storage: Temporary holding of MWS pending collection, transportation, treatment or disposal as in containers, tanks, waste piles (see temporary storage).

Storage Containers: Vessels used to contain MSW during storage.

Strategic Planning for MSWM: Planning process for the long-term, simultaneously meeting short-term needs, and flexible enough to react to changes that are anticipated to occur in the future. Strategic planning places MSWM within the context of the society for which it is designed, fitting it in with related sectors such as public health and the overall development plan of a country. Two elements can be distinguished within the strategic plan: the overall strategy or vision over the long term and the action plan for immediate implementation.

Strategy: Develops MSWM at the metropolitan level within the overall policy, taking account of all the strategic aspects as identified within the overall Conceptual Framework. The three principal strategic dimensions at the core of MSWM are:

  • What is the scope of MSWM activities that need to be addressed?
  • Who are the actors and stakeholders who will implement various activities?
  • How should the strategic objectives and issues be addressed?
    The strategic component within the strategic plan also takes the How? question to the next level of detail. For example, all the technical level of providing facilities for the recycling, treatment and disposal of MSW, the strategy will focus on establishing a broad framework indicating, in outline terms, the types of facilities, where and when those facilities are to be build, their capacity and the organisational/institutional arrangements for their provision, funding and management.

Street Sweeping: Handling, collecting and removing dust/sand, dirt and litter. In low-income countries streets may also contain appreciable quantities of household waste, drain cleanings, human and animal faecal matter. See also Public Cleansing.

Subordinate Municipal Legislation: Defined as a legislation applicable and enforceable only within the legal borders of a municipality. By-laws or municipal ordinances cannot be contradictory to national legislation.

Surface Emission Monitoring: Involves looking for areas where there is landfill gas venting to the atmosphere. Slopes, fissures, and surface areas around gas collector pipes are common points places for leaking gas.

Surveillance System: A series of monitoring devices designed to check on environmental conditions.

Synthetic Liner: A type of liner consisting of plastic membrane, instead of soil and are used in landfilling. Synthetic liners are less permeable, thinner and more flexible than soil liners.

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Targets: Referring to or relating to result(s) aimed at by carrying out an action(s). An objective is usually qualitative while a target is more specific or quantitative.

Technical Assistance: The provision of specialised technical resources, often under international arrangements to an organisation to assist it to achieve its objectives as to build internal capacity through training or improved management systems.

Temporary Storage: Temporary holding of MWS pending collection, transportation, treatment or disposal as in containers, tanks, waste piles (see storage).

Tertiary Collection System: Municipal solid waste collection from recycling centres and transfer stations and transport to treatment facilities and/or landfills.

Thermal Treatment: Use of elevated temperatures to treat MSW. (See incineration).

Tipping Fee: A fee for unloading MSW at a landfill, transfer station or recycling facility.

Tipping Floor: Unloading area for vehicles that are delivering municipal solid waste to a transfer station, or municipal waste treatment facility.

Tonnage: The amount of waste that a landfill accepts, usually expressed in tons per month. The rate at which a landfill accepts waste is limited by the landfill's permit.

Tools for MSWM planning: The working tools that are employed to plan MSWM operations. These may come in a variety of forms, and can be very simple (eg a checklist) or highly complex (a computer supported simulation program). Tools are ideally anchored within the frame of a methodology.

Topography: The physical features of a surface area including relative elevations and the position of natural and man-made features. It is important criteria in landfill site selection process.

Toxic: Harmful to living organisms.

Toxic Pollutants: Materials that cause death, disease, or birth defects in organisms that ingest or absorb them. The quantities and exposures necessary to cause these effects can vary widely.

Toxic Waste: A waste that can produce injury if inhaled, swallowed, or absorbed through the skin (see: hazardous waste).

Transfer: The movement of MSW between different stages in the handling, collection and transportation process.

Transfer Point: A designated point, often at the edge of a neighbourhood, where small collection vehicles (such as hand carts) transfer MSW to larger vehicles for transport to transfer station, recycling centre and/or landfill sites.

Transfer Station: 1. A facility at which municipal solid waste from collection vehicles is consolidated into loads that are transported by larger trucks or other means to more distant landfill sites. 2. A transfer stations can be adapted to serve also as a materials recovery facility.

Transportation: The physical process of moving waste.

Trash: Material considered worthless, unnecessary or offensive that is thrown away. Generally defined as dry municipal solid waste material (eg paper, cans and bottles), but in common usage, particularly in North America, it is a synonym for rubbish, or refuse.

Treatment: Any method, technique, or process designed to remove s olids and/or pollutants from MSW streams, effluents, and air emissions.

Treatment Plant: A structure built to treat municipal wastewater before discharging it into receiving waterbody.

Trench Method: A method by which solid and/or liquid waste is disposed in trenches in a landfill.

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Urban Agglomeration: Total contiguous heavily populated area around a city, which may spill over defined political boundaries.

User Charges: Payment for a service by the users of that service. Are a preferred means of raising new revenue because they can be presented and justified to the public on the grounds that they are required for and will be used in the provision of an important public service such as MSWM. See also Direct Charges and Indirect Charges.

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Vehicle Maintenance: Maintenance of vehicles and equipment are actions needed to ensure that usually problematic (partly as a result of procurement) or overly sophisticated vehicles (which cannot be serviced locally and whose spare parts are expensive and difficult to obtain) are kept operational.

Vehicle Productivity: A measure of the efficiency of use of MSW collection vehicles. Productivity may relate to indicators such as weight or volume of MSW carried by the vehicle in a given time period.

Vehicle Route: The route followed by MSW carrying vehicles during collection or disposal activity.

Vertical Well: The most common type of landfill gas collector. It can be installed at any time. It is drilled into the landfill by normal well drilling equipment. A pipe is installed in the well bore and packed with gravel.

Virgin Materials: Resources extracted from nature in their raw form, such as timber or metal ore.

Virus: The smallest form of micro-organisms capable of causing disease.

Void Ratio: The relationship between the voids or spaces in disposed wastes and consolidated waste.

Volume-Based Fees: A fee paid to dispose of MSW at a facility such as a landfill, based on the volume of the MSW being disposed of.

Volume Reduction: Processing MSW to decrease the amount of space they occupy, usually by compacting, shredding or incineration.

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Waste: 1. Unwanted materials left over from any human activity. 2. Refuse from places of human or animal habitation. Waste may be generically defined as heterogeneous mixture of material which is discarded as superfluous and has no further use or value to its owner. The EC Framework Directive on Waste defines waste as "any substance or object which the holder discards or intends or is required to discard". In waste planning there are various categorisations of waste (eg municipal solid waste, controlled waste, hazardous waste etc), and the terms relevant to this guide have been defined elsewhere in this glossary.

Waste Arriving at a Disposal Site (WAD): The quantity of MSW which is received at the disposal site from haulage vehicles. This may be less than the MSW hauled (WH) as a result of spillage or further scavenging during transit.

Waste Arriving at a Transfer Site (WAT): The quantity of MSW which is received at the transfer station from collection vehicles. This may be less than the MSW collected (WC) as a result of spillage or further scavenging during transit.

Waste Available for Collection (WAC): The quantity of MSW which can physically be collected by collection workers and vehicles.

Waste Collected (WC): The quantity of MSW in a given time period which is collected from municipal and domestic properties and other collection points.

Waste Collector: A person employed by a local authority or a private firm to collect MSW from residences, businesses, and community bins.

Waste Disposed (WD): The quantity of MSW going to final disposal at the landfill or dump.

Waste Exchange: Arrangement in which companies exchange their wastes for the benefit of both parties.

Waste Feed: The continuous or intermittent flow of MSW into an incinerator.

Waste Generated: The total amount of MSW arising from a generator. Includes both waste presented for waste collection and waste sold or presented for recycling.

Waste Hauled (WH): The quantity of MSW transported to the final point of disposal.

Waste Management Hierarchy: The waste management hierarchy is a symbol for the strategic options available for dealing with MSW and their desirability. An adapted version of the hierarchy presents the more `desirable' waste management pr actices at the top of the hierarchy (avoid, minimise and/or recover material) and the least `desirable' practices at the bottom (treatment and/or disposal in landfill), with dumping "floating" around the bottom, not even recognised by the MSWM concepts as an option in industrialised countries of the West.

Waste Minimisation: Measures or techniques that reduce the amount of wastes generated during industrial production processes; the term is also applied to recycling and other efforts to reduce the amount of waste going into the waste management system (also waste reduction).

Waste Picker: A person who picks out recyclables/ reusable materials from mixed MSW whenever it may be temporarily accessible or disposed of (see also: scavenging; informal sector).

Waste Picking: A process of extraction of recyclables and reusables materials from a mixed MSW for further use and/or processing.

Waste Stream: The total flow of MSW from homes, businesses, institutions, and manufacturing plants that are recycled, burned, or disposed of in landfills, or segments thereof such as the "residential waste stream" or the "recyclable waste stream".

Waste-to-Energy Plant: Combustion of MSW to generate electrical energy or heat

Waste Treatment and Disposal Facility (WTDF): A MSW facility comprising of MSW treatment (i.e. composting and/or incineration) and landfill for final disposal of residues.

Waste Treatment Stream: The continuous movement of MSW from generator to treater and disposer.

Waste Types: In general, MSW include the following main groups of different waste types: household waste, commercial waste, institutional waste, street sweepings, construction debris, sanitation residues and industrial waste (see also MSW Composition).

Wastewater: The spent or used water from a home, community, institution, farm, or industry that contains dissolved or suspended matter (see municipal wastewater).

Wastewater Treatment Plant: A facility containing a series of tanks, screens, filters and other processes by which pollutants are removed from municipal wastewater.

Weigh Scales: Also weightbridge.The means for reaching an accurate estimate of the quantity of waste entering a disposal or large transfer site. These scales are large enough to accommodate vehicles of all sizes coming to the site.

Wet/Dry Collection Systems: A collection system that allows wet organic materials to be separated by generators from dry MSW. Wet organic materials are suitable for composting, while dry materials are non-organics that may include recyclables.

Wetlands: An area that is regularly wet or flooded and has a water table that stands at or above the land surface for at least part of the year. Coastal wetlands extend back from estuaries and include salt marshes, tidal basins, marshes, and mangrove swamps. Inland freshwater wetlands consist of swamps, marshes and bogs. Dumps are often found on wetlands.

Wet Scrubber: Anti-pollution device in which a lime slurry (dry lime mixed with water) is injected into the flue gas stream to remove acid gases and particulates.

Wheel Cleansing: The process by which dirt and mud adhering to the wheels of vehicles that have travelled over a landfill site is removed, before they gain access to public roads.

White Goods: Large household appliances such as refrigerators, stoves and/or washing machines (see bulk waste).

Windrow Composting: A method of composting municipal solid waste by placing it in large, elongated piles and turning it manually to allow aeration.

Working Face: The length and width of the raw in which municipal solid waste is being disposed at a landfill. Also known as the tipping face.

Working Group: Used here to denote the team responsible for preparing the strategic MSWM plan. The Working Group must develop close links with the Steering Committee and it will take on the role of translating the requirements of the Steering Committee into practical measures for action, while at the same time, informing the Steering Committee of technical and methodological issues and measures which will affect the overall plan.

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Yard Waste ( Yard Trimmings): The part of MSW composed of grass clippings, leaves, twigs, branches, and garden refuse.

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