Do the biosolids contain heavy metals and, if so, how are they controlled?
Metal concentrations in Halton biosolids are relatively low and consistently comply with Ontario Guidelines for biosolids land application. Biosolids metal concentrations in Halton and throughout Ontario have been significantly reduced over the past fifteen to twenty years due to concentrated efforts in monitoring and controlling industrial discharges, enforcing discharge by-laws, and improved municipal wastewater treatment. The amount of metals in Halton’s biosolids poses no risk to crops, animal or human health, and contribute insignificantly to the background metal levels that occur naturally in our soils and environment.
