WC128 JanFeb2023 - Magazine - Page 24
WASTEWATER
Land application of
biosolids promotes
circular economy as it
enhances soil health by
returning nutrients and
micronutrients back to
the land.
WHAT’S IN A NAME?
perfluorooctane sulfonate (PFOS)
CURRENT STATE
POTENTIAL FUTURE TREND
Thermal
Treatment
perfluorooctanoic acid (PFOA)
PFAS
Impacted
Biosolids
Landfilled
Landfilled
Thermal
Treatment
Land Application
phased out in both the United States and Canada,
reducing potential risk. But it should be kept in mind
that not all municipal wastewater biosolids are the
same. Rather than limiting the land application of
all the biosolids with regulations, eliminating those
source-specific biosolids will certainly reduce the
risk further and keep the biosolids land application
practice effective and beneficial.
Technology and treatment trends
Because there are so many forms of PFAS and treatment options, EPA researchers have developed PFAS
Thermal Treatment Database (PFASTT), an online
centralized database to record reliable references, that
provides referenced information on the use of different thermal treatment processes for the remediation
of PFAS, and can be used by federal, state, and local
24
WATER C AN ADA • JANUARY/ FEBRUARY 2023
Although there are thousands of PFAS,
perfluorooctanoic acid (PFOA) and
perfluorooctane sulfonate (PFOS) were
two of the most commonly manufactured
and, thus, the most well-studied.
agencies and utilities in decision-making.8
With growing concerns with PFAS, USEPA is
predicting that more and more biosolids will be
thermally treated rather than sending directly to land
application in the future.
As more research on PFAS comes to light, including their quantification protocol, detection limit,
exposure impacts, and health risks, regulators and decision maker should closely follow these findings and
make them the basis of their law and enforcement
tools. While source reduction of PFAS compounds
and phasing out their usage were the most efficient
actions to reduce risk and potential concerns related
to PFAS in recycled biosolids and residuals, there is
still more work to be done.
For references visit watercanada.net/references/jf23
WAT E R C A N A D A . N E T
Truck: Getty mages, PFAS: Shutter Stock
Land Application
PFAS
Impacted
Biosolids
