We need waste disposal methods that allow the human race to live on this planet in harmony with nature, preserving our resources and habitat and leaving a legacy for our children and grandchildren that does not deprive them of opportunities. These changes will not come easily; they will require resolve and foresight. Just as a mathematician develops the proof to a mathematical theorem, we must start from a basic axiom, and step by step, following a logical progression, we must build a practical framework for waste management. We started this task in chapter 2, where we derived three general principles from the axiom of sustainable development. Can we apply these general principles to develop practical guidelines—first, to overcome the shortcomings of existing landfills, and second, to find other, innovative disposal methods that will conform with sustainable development? Let us look at each of the three principles in turn. Human health and the environment must be protected, both now and in the future. This principle is fundamental and places important constraints on the siting and design of disposal facilities, and also on the form of the waste. In particular, the final four words, “and in the future,” are very important. This principle can be satisfied in two ways: by reducing the toxicity of the wastes so they pose minimal risk, or by containing wastes so that they cannot escape and cause harm. In some cases, the latter method includes controlled leakage at a rate that the environment can assimilate without long-term degradation. Wastes must be managed so that no burden is placed on future generations and they are not deprived of the opportunities we have had. In other words, our grandchildren should not have to spend their valuable resources to solve our waste problems, nor should they be denied resources because our generation has depleted them. Neither should their health and environment be placed at risk because of our actions. The main impacts of landfills on future generations are the requirement to provide ongoing guardianship and maintenance; the loss of valuable land; and impairment of groundwater, surface water, and the atmosphere.