Operations Training/Solids Handling Training Manual Welcome to the Solids Handling Training Manual, another in the Water Environment Federation's (WEFs) Operations Training series of courses, training manuals, and study aids. The other training manual in the series is Activated Sludge Process Control. These manuals are comprehensive training tools for professionals concerned with wastewater treatment equipment, systems, and processes. They are also helpful in preparing for certification examinations and fulfilling continuing education requirements for wastewater treatment plant operators. The Solids Handling Training Manual provides a comprehensive overview of the processes of conditioning, thickening, and dewatering wastewater solids. Specific information regarding various equipment designs, process control methods, troubleshooting techniques, and safety concerns are presented. The Solids Handling Training Manual is intended for experienced operators seeking to advance their careers and/or certification level. It can provide refresher training for supervisors or others making solids-handling decisions. Therefore, this manual assumes that the student has already obtained the first level of operator certification or understands basic wastewater treatment operational processes. The manual can also be helpful for others, such as engineering students, equipment suppliers, or regulatory officials, seeking to improve their understanding of solids-handling processes in wastewater treatment. This material covers the solids-handling processes and equipment most likely to be encountered in North America. It focuses on three of the main aspects of solids handling: conditioning, thickening, and dewatering.