Decision Support System for Integrated Pollution Control (DSS)
What is it?
The Decision Support System for Integrated Pollution Control (DSS) has been developed by the World Bank, in collaboration with WHO/PAHO, to allow a rapid assessment of the pollution situation in a specific geographic location, such as a metropolitan area or water basin, and to assist in the analysis of alternative pollution control strategies and policy options. The DSS is a personal computer software program and database that has been developed from the approach and parameters provided in the 1989 WHO working document on Management and Control of the Environment. This approach generates estimated pollution loads in a study area by applying emission factors to data on economic activities. This load data can then be further processed to estimate area-wide concentrations or to examine the impacts and costs of selected pollution control measures. (Full details of the system, the basic assumptions and the base parameters are given in the manual that accompanies the software.)
The following databases are included, compiled by medium of discharge:
- pollution-intensive technological processes across all sectors of economic activity, including mining, manufacturing industries, energy, transport and municipal sectors, grouped according to the UN International Standard Industrial Classification (ISIC) at 4-digit level;
- principal control options available for each process, including 'good housekeeping' and waste prevention programs;
- emission factors associated with these processes and 'process-control option' combinations;
- normalized costs and parameters for control technologies; and
- health guidelines for air and water pollutants where applicable.
Editing and calibration features of the software allow adjustments of the default data to local conditions, when actual information is available.
Computation modules enable the user to estimate:
- air, water and solid waste emissions based on an inventory of economic activities for a given location;
- ambient concentrations of air and water pollutants by using simple (screening) dispersion models with minimum meteorological and hydrological data;
- total costs of control options by using standardized engineering-type cost functions; and
- long-run marginal cost schedules to achieve a certain level of emission reduction (or decline in ambient concentration) for a chosen pollutant.
How can it be used?
The DSS can be used by Bank staff, environmental agencies, and pollution engineers, economists and policy analysts for the following:
- information on typical emissions factors and control costs (at a generalized level);
- management of data on economic and industrial activity and related pollution loads;
- estimation of impacts and analysis of options;
- education in pollution economics and management;
As a source of information, the DSS database can provide information on pollutants, emissions factors, technological processes, control options, and unit costs that can be independently applied in other models or studies, or serve as a point of reference. However, the range and variability of the parameters included is frequently large and the database should be validated or adjusted for local conditions wherever possible.
For data management, the DSS helps to estimate pollution conditions in the absence of monitored data on emissions and ambient concentrations, and allows the major pollution sources to be identified. It can also help to highlight gaps in the existing system of data collection; it can provide a framework to organize the process of gathering relevant information in a systematic way, and the system will present the information in a convenient format as a table, chart or map. The system requires a detailed inventory of industries in a given area, including data on key inputs or/and outputs in physical units and the types of existing pollution controls, but this type of data is often more readily available than actual pollutant emissions or concentrations.
When such an inventory is not possible within the limited time and resources available, the Industrial Pollution Projection System (IPPS), that has more limited data requirements, can be used for estimating pollution loads from manufacturing industries for a number of air and water pollutants (see description of IPPS below).
As an analytical tool, the DSS is designed to help develop a cost-effective pollution control strategy across various pollution sources for a given area and identify priority investments at specific industries and in the municipal sector. The system supports integrated approaches to airshed management and wastewater treatment by capturing and evaluating the effect of all kind of sources on pollution load and ambient quality. The computer-driven analysis of pollution sources and abatement options, highlights variations in marginal costs of abatement across industries and other sources, and defines control levels and associated investments that should be adopted at different industries in order to achieve a desired pollution abatement target (in terms of either emission reduction or concentration decline of a particular pollutant) at least cost for the area as a whole. Specifically, the system estimates the amount of pollution that can be reduced without costly investments, just by improving management, operation and maintenance. The software can also be used to support the selection of alternative locations for new industries or industrial zones, as well as for urban development and expanding municipal services - it can estimate the possible effects on the pollution situation and the associated costs of compliance with environmental regulations in each proposed location.
DSS can be used as the first step in analyzing pollution control policies, such as setting environmental standards or applying economic instruments, by:
- estimating costs of attaining proposed emission and/or ambient standards in an area;
- estimating the impact on ambient quality of proposed emission/technological standards;
- allocating emission limits across pollution sources in an area in a cost-effective way;
- estimating an incentive level of an emission charge rate (using long-run marginal cost schedules) for a certain
- environmental target adopted in the area/watershed.
As an educational tool, DSS helps to make transparent key issues and causal links in pollution management. It can demonstrate the comparative effect on pollution load and ambient quality of a number of factors that can be affected by sectoral and environmental policies. It can promote public participation and consensus building by informing various stakeholders about the key pollution problems, major pollution sources and principal mitigation measures in the area.
In applying DSS, it is important to remember that the system is a rapid and rough assessment tool that can give only an indication of where problems are likely to occur, of the relative significance of different pollution sources, and of the order of magnitude of costs and effects associated with alternative pollution control strategies. Its main advantage is in helping to create a comprehensive picture of the pollution problems in an area and focus further analysis on specific priorities.
Implementing the DSS System
The DSS software runs under Windows and can be closely linked to Microsoft Excell. The database is established using Access software, although it can be manipulated directly through the DSS system. The minimum data to start the system is industrial output or input for major industries (at a four digit ISIC level), together with basic information on municipal services and traffic.
From this minimum information, the system can estimate emission loads, using the default coefficients. The estimates can be improved with further knowledge of levels of industrial pollution control and of local emission factors (which can be used to refine the default values). The system also includes simple air and water dispersion models which can offer estimates of pollutants concentrations, if basic geographical data are provided.
In addition, the system can generate total and marginal costs for the reduction of pollution loads. These costs are also based on default values and the results can be refined by introducing locally specific economic data.
The system database covers 150 industry processes and other polluting activities and 30 air and water pollutants, as well as solid wastes. An expanded database covering about 1500 activities and over 300 pollutants is also available.
Industrial Pollution Projection System (IPPS)
The IPPS is a modeling system which uses manufacturing industry or trade data to generate profiles of industrial pollution for countries, regions, or urban areas. Most developing countries have little or no reliable information about their own emissions, though many of them have relatively detailed industry survey information on employment, value added or output. IPPS converts any of these measures of manufacturing activity into estimates of the associated pollution output.
The IPPS initially combined extensive US databases on manufacturing activity (Census Bureau data) and industrial emissions (EPA data) to produce sectoral measures of 'pollution intensity, the level of emissions per unit of manufacturing activity. Pollution intensities have been developed for seven criteria air pollutants, two key water pollution indicators and also for several total indices of toxic pollution. The high level of sectoral detail in the US databases and the great diversity of the US industry make it possible to match IPPS data with the industrial profile of virtually any country but the data is being refined, based on increasing information from other countries.
The IPPS exploits the fact that levels of industrial pollution are closely related to the scale and sectoral composition of industrial activity, and to the levels of controls. The system is easy to use in conjunction with macroeconomic or sectoral projections at various spatial levels, in order to trace the potential environmental implications of industrial growth, as well as for rough screening of the current industrial emissions when more specific information is not available.
The outcomes of the IPPC, however, should be primarily used for estimating a relative change in emissions according to different scenarios of industrial activity, rather than for making conclusions about the absolute levels of industrial emissions.
The two systems are broadly compatible because they operate at different levels of aggregated data. The IPPS can be used to quickly assess the relative magnitude of emissions from different industries in cases where the application of DSS is constrained by the lack of data on inputs/outputs in physical units. However, since the scope of IPPS is limited to manufacturing industries only, it has to be supplemented with other assessment tools when analyzing the pollution situation in urban areas. Where local industrial municipal, and transport data is available or can be collected, DSS provides a greater capability to estimate loads and concentrations as well as to analyze control strategies.