The environmental pyramid: a new way to deal with solid toxic waste

Abstract

Our society produces large volumes of solid waste, including toxic chemical waste. For toxic solids, the current disposal practice is to dump them into isolated, lined pits, and cover them with a water-impermeable layer with a soil layer on top. Such waste deposits require 'eternal' control and monitoring, because they eventually do leak, contaminating the surrounding soil and groundwater. Here, it is proposed to keep these wastes above the ground, and mix them with a cement-like material, and shape this mixture into concrete slabs. The cement and the possible additives are selected for maximum waste immobilisation. The slabs are then laid on a reinforced concrete platform centred in a shallow square pit, surrounded by a ditch and stacked in the form of a pyramid. This disposal technique is safer, because it permits easy post-deposition control and monitoring. Only along the outside of the pyramid are the wastes in contact with water and only in times of rainfall. This keeps leaching to a minimum. If the small amount of water flowing down the sides of the pyramid into the ditch turns out to be contaminated, it can be cleaned in an easy and a controlled way. Even this minor and intermittent contact with water can be avoided by coating the pyramids with a water-repellant synthetic material. The constructed environmental pyramid will be a landmark, and can serve as a tourist attraction. By making the individual steps of the pyramid larger, it can also serve as a mound on which stacked housing or office buildings will be built, thus saving space as well as the cost of constructing such modern dwelling mounds, possibly in the areas that risk intermittent flooding.