WC141 MarApr 2025 - Magazine - Page 21
U.S. communities where PFAS are manufactured or from
industrial areas such as military bases, where wastewater has been
contaminated by firefighting foams or other industrial sources.
In Canada, the number of WWTFs with effluent or biosolids
classified as “industrially impacted” by high levels of PFAS
appears to be significantly lower. This is likely due to historically
lower industrial PFAS use in Canada compared to the U.S.
Currently, PFAS are not included in the Canadian Wastewater
Systems Effluent Regulations (WSER), but Environment and
Climate Change Canada and Agriculture and Agri-Food Canada
continue to monitor PFAS levels in wastewater and biosolids.
The land application of biosolids is regulated at the provincial
level, with stringent mitigation and environmental monitoring
measures in place. The Canadian Council of Ministers of the
Environment supports the land application of biosolids when
applicable provincial and federal standards are met.
Canadian utilities must balance the low-level potential risks
of biosolids with their significant benefits. Biosolids are rich in
nutrients and carbon and are commonly applied to land as an
effective and affordable soil amendment and fertilizer. They play
a crucial role in the circular economy by sequestering carbon,
returning nutrients and organic matter to the soil, enhancing
climate resilience by improving soil structure and water retention,
and reducing the need for synthetic fertilizers. The alternatives—
incineration or landfill—are costly and pose substantial
environmental risks. Therefore, the environmental benefits of land
application must be carefully weighed against any potential risks.
Most recently, on January 14, the EPA released a Draft Risk
Assessment for PFAS in biosolids for a 60-day public consultation
period. The draft states that “there may be human health risks
associated with exposure to PFOA or PFOS in all three methods
of using or disposing of sewage sludge—land application, landfill,
and incineration.” However, the EPA’s analysis does not indicate
that the general food supply is impacted by biosolids containing
PFAS.
The challenge now for utilities, regulators, and practitioners
is determining how to interpret the risk assessment, when to act,
and how to act. Reports from both Health Canada and the EPA
frequently use the word “may” when discussing potential risks,
underscoring the need for further comprehensive research on
both acute and long-term low-level PFAS exposure.
More work is needed to improve field mitigation approaches,
develop proactive surveillance programs, and provide utilities
with the tools and authority to require industries to pre-treat
effluent before discharging it into wastewater systems. Biosolids
treatment methods for PFAS are still in the early stages of
development. Without effective source control, utilities and
ratepayers will face significant and often unsustainable costs.
Enhanced monitoring can help identify contamination hotspots
and serve as a basis for implementing targeted source control
measures.
WAT E R C A N A D A . N E T
The most effective way to protect communities is to control
PFAS at the source and raise public awareness to influence
consumer behavior. Eliminating further PFAS use and capturing
existing PFAS before it reaches WWTFs are critical steps.
The EPA’s PFAS Strategic Roadmap aims to hold polluters
accountable by requiring industrial dischargers to remove PFAS
before releasing effluent into the environment or WWTFs.
In Canada, the manufacture, use, sale, and import of PFOS,
PFOA, and certain other long-chain PFAS compounds have been
prohibited under the Prohibition of Certain Toxic Substances
Regulations, 2012. Limited exemptions were granted, but most
were removed in 2022. PFAS levels across North America have
been steadily declining as these compounds are phased out.
While many questions remain, biosolids continue to be
produced, and their quality must be carefully assessed. The
risks and benefits of biosolids management must be weighed
against available alternatives. Ultimately, the wastewater industry
remains committed to protecting both the environment and
public health. Working collaboratively with industry partners,
consumers, researchers, and regulators is essential to ensuring
the safety of drinking water, effluent, and biosolids for future
generations.
LEARN MORE
WATER C AN ADA • M ARCH/APRIL 2025
21
