This guide for developing standard operating job procedures for wastewater treatment facilities is devoted to the activated sludge aeration and sedimentation process. This process is for conversion of nonsettleable and nonfloatable materials in wastewater to settleable, floculated biological groups and separation of the settleable solids from the water. The guide gives step-by-step pre-start up, start-up, operating, and shut-down instructions along with a general description of the equipment used in the process and some theoretical material. (BB)