When new pollutants start showing up in our waterways, clean-water plants often find themselves in the spotlight.
A new or emerging pollutant is detected in the water or in the tissues of fish downstream from the plants, and suddenly those plants are looked at (by some) as the source. In reality, the guilty chemical came from homes or businesses or both, through the collections system, and into the plant, which was neither designed nor required to treat for it.
Clean-water plants face the disadvantage of being at the end of the pipe, at the mercy of what comes in and, more important, at the mercy of regulators who decide what is and isn’t a pollutant that the plants need to remove, and how efficiently they have to remove it. This doesn’t just apply to new pollutants — witness what has happened to effluent limits on phosphorus in the past decade or so.
My purpose here isn’t to cast aspersions on the regulatory community. It’s to highlight the challenges that treatment plants face as new pollutants are discovered and as technology enables detection of substances at lower and lower concentrations.
When is it a problem?
Just when plants have a good handle on the traditional wastewater components — BOD, TSS, nitrogen, phosphorus — along come plastic microbeads. Pharmaceuticals. Fragrances. Insecticides. Endocrine-active compounds. And the one everybody seems to be talking about these days: per- and polyfluoroalkyl substances, or PFAS.
This month’s In My Words article takes a look at PFAS and their impact. State regulators are already taking notice. The Michigan Department of Environmental Quality last year launched an industrial pretreatment initiative aimed at PFAS. The agency noted that conventional treatment doesn’t effectively remove PFAS, which then would pass to through lakes, streams, and groundwater and into biosolids.
In Maine last March, the Department of Environmental Protection imposed a moratorium on land application of biosolids and biosolids composts out of concern over PFAS, which are chemicals used in fire retardants and various other products since the 1950s and lately have been linked to cancer, liver damage and other health issues.
Loss of control
Now consider the impact of that moratorium, issued in the very earliest days of spring, on clean-water plants with biosolids ready to go out to the farms? At the time I wrote this, it wasn’t clear whether the moratorium would be short-lived or the state would make some provision for these plants. If not, then the biosolids in all likelihood were headed for landfills, at great expense.
This is just one illustration of what can happen as research zeroes in on the effects of even low-level chemical exposure, and as our ability to detect and measure chemicals continues to improve.
Last month’s issue contained an article in which the National Association of Clean Water Agencies argued for more federal government funding for water and wastewater treatment and infrastructure, especially as regulations proliferate and become stricter.
Facilities need help
Issues like PFAS argue strongly for intervention from the state and federal levels to help find and fund appropriate treatment for these emerging contaminants. There’s also a need for research to assess accurately whether these substances actually pose threats, and under what circumstances.
The local clean-water plant can’t control what comes down the pipe, other than through targeted industrial pretreatment programs. The utilities that own those plants, and the customers of those utilities, shouldn’t be held solely responsible for the cost of solving the problems.
