The exponential rise in the urban population in the past few decades and in recent times resulting accelerated urbanization phenomenon such as increase in waste generation, energy crisis among others, has brought to the fore the necessity to develop environmentally sustainable and efficient waste management systems.

Landfill sitting is a complicated process requiring a detailed assessment over a vast area to identify suitable location for constructing a landfill subject to many different criteria. GIS offers the spatial analysis competence to swiftly do away with pieces of land unsuitable for landfill site. The suitability criteria are defined with the focus to minimize any potential health risks from direct or indirect contamination due to the propinquity of a landfill site with respect to key geographic features. Thus, the first-stage analysis using GIS is critical for the initial identification of different suitable landfill sites prior to undertaking further analyses or site investigations. Though, the initial screening is based on criteria related to environmental and ecological factors involved in the site selection process, there are certain criteria, such as impact on historical markers, public comfort, and economic factors for which data are not always readily available. Data is important ingredient in designing and construction of a landfill site. Inadequate data could impede its location and development. The following factors should be considered when using GIS in identifying suitable site for waste disposal: lake and ponds, rivers, water supply sources, groundwater table, groundwater quality, infiltration, air quality index, geology, elevation, land use and highway sensitive sites. Economic and financial analysis including finding the most cost effective route for transporting wastes and locating the most suitable land for the potential sites based on land value Developments on or too close to existing road and rail networks could obstruct transportation and may have an impact on tourism. The issue of transportation should keenly be looked at by the city authorities and waste management companies.
Accra Municipal Assembly and EPA should as a matter of urgency develop and implement proper and well engineered landfill sites. The state of the so called landfill sites in Accra does not only pose potential environmental risk but health risk as well. The production of leachate contaminates under and surface water leading to the spread of water borne and cancerous diseases.
The amount of waste sent to landfill should be reduced in order to minimise its affects. Waste such as organic could be composted either using widow or in-vessel composting or anaerobically digested. In the case of Accra, due to either lack of information or inability to distinguish which waste should be disposed, you see plastics which could be recycled indiscriminately dumped in the so called landfill sites.

Stephen Kansuk
Kansuk_stephen@yahoo.com