Abstract: An ecologically clean process is described for the disposal of partially dewatered waste water sludges in combination with hazardous or noxious chemical wastes, with or without added high calorific waste from other sources which comprises, dewatering the sludge to a solids content of at least about 25% by weight, blending the dewatered sludge with any desired amount of added hazardous chemical waste up to 25% by weight or more, and with 0% up to about 35% by weight of a combustible waste from any other source having a calorific content of at least about 5000 BTU/lb. to obtain a mixture which is at least almost autogeneously combustible and then incinerating said mixture at a temperature of at least about 1400.degree. F for sufficient time to substantially completely combust the mixture to substantially odor-free off gases, said incineration being preferably conducted entirely autogeneously or with a minimal amount of auxiliary fossil fuel.