A method for using large chambers, located deep within the earth, for the disposal of processed waste is disclosed. In this context, waste includes solid waste from sewage, and other organic-waste materials from urban, agricultural or industrial sources. These wastes will be processed by mechanical pulverization and hydration to produce a slurry, which will be injected into the well's chamber. The anaerobic condition in the chamber will be conducive to the production of gases, especially methane which will be harvested as a source of industrial fuel. Hydrogen, ammonia and other gases will also be harvested. This system will alleviate the acute problem of disposal of wastes from urban agricultural and industrial sources. It will decrease pollution of the air with greenhouse gases and pollution of the land area water with organic wastes and also release of disease-causing pathogens. The system may be adapted to facilitate the disposal of nuclear wastes.