79. This newspaper editorial concludes that our city should build a plant for burning trash in order to avoid the serious health threats associated with many landfills. The author adds that an incinerator could offer economic benefits as well, since incinerators can be adapted to generate small amounts of electricity for other uses, and since ash residue from some kinds of trash can be used as a soil conditioner. Even if these claims are true, the author s argument is unconvincing in three important respects. To begin with, the author fails to consider health threats posed by incinerating trash. It is possible, for example, that respiratory problems resulting from the air pollution caused by burning trash might be so extensive that they would outweigh the health risks associated with landfills. If so, the author s conclusion that switching to incineration would be more salutary for public health would be seriously undermined. Secondly, the author assumes that discontinuing landfill operations would abate the heath threats they now pose. However, this is not necessarily the case. It is possible that irreversible environmental damage to subterranean water supplies, for example, has already occurred. In this event, changing from landfills to incinerators might not avoid or abate serious public health problems. Thirdly, the author s implicit claim that incinerators are economically advantageous to landfills is poorly supported. Only two small economic benefits of incineration are mentioned, while the costs associated with either burning trash or switching refuse disposal systems are ignored. In all likelihood, such costs would be significant, and may very well outweigh the economic benefits. In conclusion, the author s argument provides inadequate justification for switching from one disposal system to the other. As it stands, the argument takes into account only a limited number of benefits from the change, while addressing none of its costs. To better evaluate the argument, we must first examine all the health risks posed by each refuse disposal system and conduct a thorough cost-benefit analysis of each system, taking account of the cost of the new system, the cost of the changeover itself, and the expected costs to the community of health problems resulting from each system.