In today’s tough economic climate, biosolids management faces new challenges in keeping their process not only sustainable but also cost effective. Increased public scrutiny and changing regulations have reduced the options for disposal making biosolids management a more complex task.
In the US, biosolids management may differ from state to state. In California, for example, regulatory and legal issues reduce the availability of agricultural property for land application, but in the central parts of the country the practice is generating greater acceptance. Western Arizona receives biosolids from Southern California while places like Pittsburgh send biosolids to Ohio and Colorado receives its biosolids from New York.
While farmers are enjoying the benefit of these inexpensive fertilizers, municipalities are slowly encountering pressure to manage biosolids for their own use. The problem gets even more complicated by resistance from neighbors and permitting authorities who oppose the idea and are raising significant hurdles.
One solution is the growing trend of municipalities forming a coalition to build and operate a regional facility to manage their biosolids. The burden of designing, financing, building, and operating this facility is usually given to private entities so that it won’t affect the municipal budget significantly.
Because of increased scrutiny, there is a growing desire for cleaner biosolids before distribution in the markets. Even though scientific literature has not demonstrated any issues with the current legislated limits, the United States Environmental Protection Agency (US EPA) is mandated to address this concern and potentially reduce it even further.
Pharmaceuticals and Personal Care Products (PPCPs), which are a part of biosolids, have yet to be regulated and the EPA has been tasked to develop limits for these products even if the analytical methods for quantifying their levels have yet to be proven and approved. It’s an issue that municipalities have now paid more attention to.
These municipalities are likewise being asked to take measures against odours from the treatment of the biosolids, as well as how it is transported, and how the products are the finally utilized. Just like wastewater treatment, odour from biosolids is a challenge that needs to be addressed efficiently, without offending the neighboring areas during its processing. During the stages of pre-conditioning, dewatering, drying, and truck loading, odours are released which can offend the community, at roadways during transport, and finally at the sites where they are delivered.
There is a saying that “You smell with your eyes!” so even if a facility is able to contain the odours to a minimum, anything that might be unsightly to look at as a result of poor maintenance or housekeeping may evoke complaints about the odours so great care must be taken to provide a hygienic looking environment.
There are several measures that need to be taken to ensure biosolids sustainability. One is to maximize the methane produced from anaerobic digestion and the thermal energy potential of these biosolids. Another is to assess the greenhouse gas implications for the different management solutions. It is also important to review the sustainable return on investment for undertaking this process for the investors and the community as well as implementing an effective cost strategy. A program for biosolids management diversification is also key to ensuring adaptability to changing needs.
In the end, sustainability of biosolids management would depend on all the stakeholders involved, from the farmers to the municipalities. A “Systems Thinking” approach is encouraged to guarantee an enduring and environmentally sound solution.
If you are a municipality in Ontario and in need of a biosolids management solution, please feel free to contact us on 1 (877) 479-1388.
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