Developing a Capital Improvements Plan for the 64 Dry Ton Per Day JEA Buckman Regional Residuals Management Facility

JEA is located in Jacksonville, Florida and serves customers in Duval, Nassau and St Johns Counties. JEA utilizes a centralized approach for residuals management. The Buckman Residuals Management Facility (RMF), located at the JEA Buckman Street Water Reclamation Facility (WRF), processes residuals produced at each of the satellite treatment facilities owned by JEA over a 3-county service area. Residuals are transported to the Buckman RMF either by truck or by pumping. Residuals from the Mandarin WRF (permitted 7.5 mgd capacity) are being thickened to approximately 4.0 percent prior to shipment via tanker trailer to Buckman RMF where they are introduced directly to the anaerobic digesters. The biosolids generated at the other 11 treatment facilities are trucked as unthickened sludge.A capacity analysis report prepared for JEA showed that the permitted capacity of the facilities would not be exceeded within the next 10 years. However, a tracer study which was performed on the anaerobic digesters revealed that approximately 25 to 30 percent of the existing volume is inactive due to grit and trash accumulation. In addition, the existing covers were exhibiting signs of failure that must be addressed within the next several years. Currently, the two existing digesters are operating with a solids retention time (SRT) between 10 to 15 days. Therefore, it was determined that JEA did not have sufficient capacity to take either digester out of service for cleaning and cover replacement.The JEA and CDM team worked together to evaluate the existing equipment at the Buckman RMF based on the current and projected residual loading conditions and to prepare a capital improvements plan (CIP). The plan identified the details of the projects required to allow JEA to take one digester out of service for maintenance, and to improve the reliability and effectiveness of the existing biosolids management system over the next 5 years. The CIP mainly focused on the anaerobic digestion process to increase the operational flexibility by adding new digesters and cleaning the existing digesters after the new digesters are in operation.The project team also performed a condition assessment evaluation of the processing equipment and developed a replacement funding program for the existing anaerobic digestion and thermal drying system components at the Buckman RMF. The cost for replacement funding over 5 years was determined based on the evaluation of the existing equipment and the life expectancy of each piece of equipment. As a result of this study, it was decided that JEA should allocate between 0.5 million and 1.6 million every year for the next 5 years. The replacement funding program will allow JEA to anticipate replacement costs and to fund for these costs in their 5-year financial plan.This paper presents JEA's capacity challenges to centralize residuals management at one facility. It will also present the CIP developed to address these challenges for the next 5 years, and show the steps taken to generate a plan for funding replacement of the biosolids processing equipment.