How Is Waste Managed

Essentially, the final management option for residual waste is disposal to landfill. Everything else might be viewed as some form of pre-treatment or waste avoidance. However, it is clear that all of the alternative management options have a role to play, to help minimise the amount of material which can be said to have been wasted. Indeed, some optimistic policy-makers do not regard even landfill disposal as an ultimate waste of resources, preferring to regard this as a long-term storage element of a wider Zero waste policy.

The range of options available once waste is created is limited to recovering materials and/or energy resources before the final, useless residues are landfilled. The techniques applied depend on the materials in the waste, the waste management systems available locally or regional and the market opportunities. The selection depends particularly on the established waste management policy. Treatment methods are used to reduce the amount of residual waste for disposal, and to achieve one or more of the following goals:

• reduce the potential environmental impacts of the waste

• separate and recovery materials or energy

• reduce transport costs

• volume of landfill needed

• minimise overall costs

7 Eurostat Waste generated in Europe - data 1985-1997, ISBN 92 828 7941 0, 2000.

Table 3 Environmental impacts of waste management methods

Landfill

Composting

Incineration

Recycling Transport

Water

Soil

Landscape

Ecosystems

Urban areas

Emissions of methane (CH4) and carbon monoxide (CO) odours

Leaching of salts, heavy metals, biodegradable and persistent organics to groundwater

Accumulation of hazardous substances in soil

Soil occupancy; restriction on other land uses

Contamination and accumulation of toxic substances in the food chain

Exposure to hazardous substances

Emissions of methane (CH4) and carbon monoxide (CO) odours

Soil occupancy; restriction on other land uses

Contamination and accumulation of toxic substances in the food chain

Emissions of SO2, NO*, HC1, HF, NMVOC, CO, CO2, N20, dioxins, furans, heavy metals (Zn, Pb, Cu, As)

Deposition of hazardous substances on surface water

Landfilling of ashes and scrap

Visual intrusion; restriction on other land uses

Contamination and accumulation of toxic substances in the food chain

Exposure to hazardous substances

Emissions of Emissions of dust, NOx, dust SO2, release of hazardous substances from accidental spills

Wastewater Risk of surface water and discharge groundwater contamination from accidental spills

Landfilling of Risk of soil contamination final residues from accidental spills

Visual intrusion

Traffic

Risk of contamination from accidental spills

Risk of exposure to hazardous substances from accidental spills; traffic

Figure 2 Waste management in Europe (Source Eurostat/OECD)

Figure 2 Waste management in Europe (Source Eurostat/OECD)

Austria Denmark France Germany Italy Netherlands Norway Spain Sweden Switzerland UK (1996) (1996) (1993) (1996) (1997) (1998) (1995) (1997) (1997) (1996) (1998/9)

LANDFILL ENERGY RECOVERY COMPOSTING RECYCLING

Austria Denmark France Germany Italy Netherlands Norway Spain Sweden Switzerland UK (1996) (1996) (1993) (1996) (1997) (1998) (1995) (1997) (1997) (1996) (1998/9)

LANDFILL ENERGY RECOVERY COMPOSTING RECYCLING

Waste management options after generation and before final disposal comprise:

• waste minimisation

• collection and sorting

• composting

• anaerobic digestion

• energy recovery (incineration or other more advanced thermal treatment techniques)

• incineration (without energy recovery)

Arguments over the relative merits of management options between prevention and disposal have been loud and vigorous, although during the late 1990s there were significant signs of rapprochement between the different camps. Although local circumstances may alter the priorities, it is generally true that the main purpose of a waste management policy is to reduce the scope for waste to harm the environment or public health. The European Commission has described8 the range of environmental impacts from managing MSW, as shown in Table 3.

It is clear from many sources that different countries elect to manage waste in different ways, or rather display different sets of preferences as alternatives to landfill. A study undertaken for the Resource Recovery Forum9 yielded the results shown in Figure 2, which shows that landfill dependency ranges by an order of magnitude.

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