Environmental risk of waste and its management - Environmental Deterioration and Contamination: Problems and their Management - page 150

Figure 6.6 Waste management scheme and evaluation options.
Because methane loss is a key factor in the above calculations, and anaerobic
digestion proved to be the best alternative for food and garden waste, it should be noted
that this is valid only if the manufacturers can ensure 2% of methane loss. According
to other estimations, the methane loss may even reach 40%, including transport and
uncontrolled emissions, which means that the methane production estimated by LCA
is associated with the quality level of the technology. This example demonstrates the
importance of data quality and validity in these calculations. The amount of waste is
also an important factor in selecting the most appropriate waste management option
(small amounts have less transport-dependent impacts than large amounts).
A second important tool to evaluate waste utilization is ERA of chemicals. It
considers the constituents of the waste to be chemical substances. When large volumes
of waste are used as raw material in production, manufacturing, or in the energy sector,
this approach is not only logical, but also an obligation under the REACH regulation.
The hazard of the waste depends on the intrinsic characteristics of the waste con-
stituents. The risk of the hazardous waste components depends on the applied amount,
on the way and location of application (i.e., the vulnerability of the environment), as
well as on the control measures.
Hazards and values of wastes are the fundaments of their utilization, but the final
risks and benefits will be determined together with the environment and its users as
indicated in Figure 6.7. Land uses of different sensitivity accept different levels of
hazard. Industrial or agricultural land, a residential area or a natural park can be
loaded by different amounts of hazardous materials to reach the acceptable limit. In