Handling Residuals Management in a Changing World: Lee County Utilities Regional Biosolids Management Plan

Many Florida public utilities continue to dispose of Class B sludge through various land application methods permitted under current Florida Department of Environmental Protection (FDEP) and the Federal 40 CFR 503 regulations. However, in rapidly urbanizing areas, such as Lee County (FL), loss of agricultural land is placing increased pressure on biosolids generators to pursue innovative management practices to dispose of wastewater treatment residuals. Furthermore, an increase in local and regional regulatory constraints on land application is further complicating residuals management activities.To address the loss of agricultural land application sites and local/regional constraints, Lee County Utilities (LCU) initiated an investigation into the feasibility of constructing and operating an alternate biosolids management facility capable of producing a Class A quality end-product to offer a wider variety of options for disposal. The final feasibility report included considerations for regulatory issues, end-product market potential, a variety of possible technologies, alternate site locations, and comparative costs to present operations. The report concluded that a Class A facility was feasible but that present worth costs would be slightly higher than continuing present practice of disposal of Class B biosolids at a land fill if the County were to self-perform all hauling. However, in the interest of promoting beneficial re-use of biosolids, the Lee County Board of Commissioners unanimously approved that the proposed biosolids facility, utilizing a thermal dryer, be designed and constructed. The facility will be located on Lee County's Solid Waste Waste-to-Energy (WTE) Facility and will utilize excess steam produced at the WTE facility as the heating medium. The RFP document development to procure a design-build-operate firm is ongoing. This paper high-lights the main aspects of the report and the common issues that typical municipalities are facing in the ever declining world of Class B disposal options.