Overall, costs can be
distinguished between ‘‘internal’’ and ‘‘external,’’ whereby internal
costs are monetary costs occurring both inside and outside the
waste management system, while external costs (also termed
‘‘externality’’ costs) occur outside the economic system (also called
‘‘non-marketed goods/services’’ because they have no direct monetary
value in the market). Internal costs can be measured either in
market prices or in factor prices, the latter are market prices
excluding transfers (taxes, subsidies, fees and duties used to distribute
income between different agents in society, but which do
not represent any resource reallocation)