Overview of Biosolids Program
The City of Lawrence Wastewater Treatment Plant has been dedicated to recycling in all aspects of its operations, including biosolids management. Land application, or other means of recycling, has been used for most or all of the biosolids produced by the City's sole wastewater treatment plant for nearly 50 years (since 1956). Currently, 90-95% of the biosolids are applied to area agricultural fields as a fertilizer and organic matter source. The remainder is made available for public distribution as exceptional quality/Class A for residential uses on landscaping, gardening and other appropriate uses.
Over the years, the City's biosolids management methods have evolved to meet its needs. Following the initial construction of the City's wastewater treatment plant in 1956, local residents were allowed to remove biosolids from the sand drying beds themselves for use on gardens, landscaping and lawns. Some of the material was also used on City park landscaping and beautification projects. The addition of secondary treatment created additional biosolids to be managed which were land applied via an umbilical hose and applicator system to City-owned agricultural fields surrounding the treatment plant. This method continued until EPA 40CFR Part 503 required the City to add additional farmland for land application to continue. At that time, private landowners and farmers were approached to participate in the City's program. Distribution to the public continued following additional detention time and analysis to verify EQ/Class A quality.
The City of Lawrence further committed to beneficial use in 1996 by creating the position of Residuals Coordinator. The responsibilities of this position include overseeing and organizing the biosolids programs and general biosolids management, farmer/program participant relations, media relations/public education and evaluation of options necessary for project and contract management.
Although liquid application was successful, the City invested in a dewatering facility, including two 2-meter belt filter presses, 4-5 months of above ground storage and associated facilities. Currently, anaerobically digested biosolids are belt pressed to approximately 20% solids, stored until conditions are appropriate for land application and then transported to fields for application. Application events are planned around the cropping season, usually spring before planting, summer following wheat harvest or on grass and fall after harvest (March, July and November respectively). Crops that benefit from the biosolids include corn, soybeans, wheat, hay and pasture. Some reclamation has also been done to achieve growth on final cover of a local landfill in the past.
The City contracts with a private contractor to provide the equipment, personnel and associated services for the biosolids removal, transportation, application and associated activities with close oversight and monitoring by City personnel in all aspects of the process. The City maintains control of the land application projects as well as communication with the contractor, farmer/land owner and other interested parties.
Exceptional Quality/Class A biosolids are provided to the public as available at no charge and advertised to the public via various avenues of public announcements. This give away program has continued as a vehicle to educate the public on biosolids, wastewater treatment and land application.
Additionally, the City committed to developing an environmental management system for biosolids and became a charter demonstration agency with the National Biosolids Partnership's EMS program. A 2005 third party audit verified that the standard was met and certification was granted. Annual interim audits are conducted as maintenance.
The most recent improvement to the program has been the addition a cover (roof) to our biosolids storage area. This will prevent additional moisture (rain and snow) from entering the cake biosolids storage which will maintain the consistency of the biosolids, ease hauling and increase the quality of the material.
The biosolids program has enjoyed a high degree of public acceptance from both City residents and the local farming community. Some of its success may be due to the longevity of the programs which may have familiarized local residents with such practices. Other efforts have been made to educate the public about wastewater treatment and the various uses of biosolids. These have included plant tours, information booths, news articles, television segments, information folders and a web page. The public education efforts have attempted to target the various segments of the community. In addition, cooperative efforts have been made with industry professionals and other interested parties who may act as spokespeople for the program if the need should arise.
The City of Lawrence has been in compliance with the EPA regulations (40 CFR Part 503) since its adoption in 1993. Prior to that time, the State of Kansas did not enforce specific biosolids regulations. Likewise, there are no local ordinances or regulations addressing biosolids management activities.