Development of overall Bio-solids strategy

The town of Espanola will undertake a feasibility study that will result in an overall biosolids strategy in wastewater management. The goal of this study is to develop a sustainable bio-solids strategy that targets best viable options of bio-solids management at the Espanola Wastewater Treatment Plant (WWTP). The options must be economically feasible and eliminate the need to transport the liquid sludge to Sudbury 150km away. The study will also provide additional avenues for sludge management for the Town through further processing, including composting or other processing methods. For example, the study will also investigate potential waste collection systems including Source Separated Organics (SSO) and recycling programs, and how alternate systems may be incorporated into the handling of the biosolids sludge. Project milestones will include a review of the current system’s WWTP plant flows, solids production, haulage data and previous studies while also considering possible implications for anticipated regulatory changes. The town, with its consultants, will then review potential dewatering and stabilization options with a cost/benefit analysis of implementing a new solids process with energy and resource recovery. Finally, consideration of possible dewatered cake utilization options will inform a review of the Town’s current waste management contract, landfill practices and recycling objectives. This project could result in a net fuel and electricity reduction, allow for more clean water to be released from the wastewater treatment plant, and provide solid material to be used in proposed composting facilities and waste diversion programs. GHG reductions by eliminating the need for transport to Sudbury are estimated at 16.5 tonnes of CO2 eq., based on an annual haulage of 73 loads at a 300 km round trip. In addition, the electrical savings with the elimination of the WWTP’s aerobic digestion process may exceed 200,000 kWh/year, which would result in an additional 8.2 tonnes CO2 eq./year reduction. Based on the Town’s baseline GHG report from 2013, the project could lead up to a potential net GHG reduction of 64%. Further to improving the storage and application of the sludge, dewatering the sludge could also increase the volume of water reintroduced to the environment, helping to maintain the natural water cycle in the area. One option for the dewatered cake is to treat and market that material as a CFIA fertilizer product. This has the benefit to the environment to offset the use of synthetic fertilizers, as the residual material left after digestion has a high nutrient content. Overall, this project provides a model to municipalities to leverage their assets and convert them into revenue producers while promoting climate mitigation technologies and practices.