4.2.4. Threats
4.2.4.1. Management of public safety and prevention of illegal
dumping incidents. As aforementioned, accumulated explosive gas
in the closed landfills, e.g., methane and VOCs, would lead to the
risk of fire accidents. Besides, considering the case of Guam, unexplored
bombs might be disposed of in landfills. For this reason, it is imperative to prevent
fire accidents at such a highly risky site. Comprehensive waste
composition survey should be implemented prior to the future
reclamation of a closed landfill.
Furthermore, most landfills are located at rural areas far from
the CBDs due to the NIMBY syndrome. Therefore, during the night
time, the safety system should be well established for preventing
crime and even illegal dumping incidents in such open spaces. In addition, as the degree of biodiversity might be augmented at
closed landfills with adequate vegetation, the spaces might be
dangerous to the public because the sites can serve as habitats for
harmful species, e.g., venomous snakes. The municipalities should
pay special attention on the aftercare management of closed
landfills whether they are open to the public or not. 4.2.4.2. Adjustment of relevant legislation. Regarding the power
generation from methane at closed landfills, the methane emission
is quite time-dependent in line with the organic component
decomposition, as the cases in Taiwan indicated. In order to achieve
the goal of GHG emission mitigation and energy recovery simultaneously,
it is imperative for regulators to provide long-term
economic incentives for the stakeholders. With sufficient economic
incentives considering the potential environmental benefits,
the relevant industry can be promoted and economically viable at
the markets. Furthermore, for material recovery, the prices of recyclables
have to be competitive with the existing margin materials.
Meanwhile, the relevant supportive law and regulations
should be amended and adjusted according to the conditions in
each country.
To sum up, Table 3 outlines the key observations
aforementioned.