EPA study questions safety of sewage sludge as fertilizer. Will it impact Charlotte Water?
Charlotte Water “is closely monitoring” a new federal report on potential health risks of sewage sludge spread on farmland as fertilizer — a practice the utility has used for years.
A new risk assessment released in January by the Environmental Protection Agency found the sludge —generated during the wastewater treatment process — can contain levels of certain synthetic chemicals dangerous to human health. The sludge is officially called biosolids.
The practice is particularly risky, the EPA found, for people who live on or near farms that fertilize with contaminated biosolids.
Sludge generated by Charlotte Water’s treatment plants is recycled on more than 10,000 acres of private farmland in North and South Carolina, according to the agency. The work has generated controversy over the years throughout the Charlotte region.
The utility is “carefully considering” the latest information from the EPA, said spokeswoman Jennifer Frost, who emphasized the draft risk assessment “is not a regulation.”
“Charlotte Water remains dedicated to ensuring the public and environment are protected while following the best available science and regulatory guidelines,” she said in a statement.
It’s not just Charlotte — researchers at NC State linked biosolids to high chemical levels in some surface water, private wells and drinking water sources in the Raleigh-Durham area, WRAL reported.
Charlotte Water’s sewage sludge program
Charlotte’s program generates “Class B” biosolids, meaning the sludge can only be spread on land where animal feed crops are grown, not land producing crops for human consumption.
The farms that receive the sludge are permitted by the North Carolina Department of Environment Quality or South Carolina Department of Health and Environmental Control.
The permitting process has sparked fighting in the Charlotte region over the years between farmers who say the sludge is a cost-effective fertilizer and residents concerned about the potential health and environmental impacts.
Charlotte Water temporarily withdrew a permit to expand its biosolids program into Rowan County in 2015 after backlash from residents, The Salisbury Post reported at the time. Later that year, the utility cut significant acreage from its program during the re-permitting process, the Observer reported.
Now, the agency recycles sludge on more than 17,000 acres of private farmland in North and South Carolina, Frost confirmed.
EPA warns of potential biosolids risks
The EPA’s latest report found “there may be human health risks exceeding the EPA’s acceptable thresholds” posed by sludge spread on farmland that contains two types of chemicals, PFOA and PFOS.
Often called “forever chemicals” because of how slow they are to break down, exposure can lead to an increased risk of some cancers, decreased fertility, developmental delays in children, hormonal imbalances and immune deficiencies, according to the EPA.
“Traditional wastewater treatment technology does not remove or destroy PFOA or PFOS, and these chemicals typically accumulate in the sewage sludge,” the EPA’s risk assessment said.
The chemicals can get from soil into groundwater, lakes, streams, fish, plants and livestock, raising “questions about the potential risks” of them showing up in sewage sludge used as fertilizer.
The report specifically cites risks for people who live on or next to farms that use biosolids, those who “rely primarily” on those farms’ food and drinking water and those who may be drinking contaminated groundwater.
It didn’t assess the risk to the general population.
Will Charlotte Water change practices?
Charlotte Water “continues to monitor and assess potential PFAS sources,” Frost told the Observer.
That work includes considering alternative uses of biosolids as well as a pretreatment program and implementing industry best practices and management options recommended by the EPA.
Frost said the EPA’s draft risk assessment “is missing important provisions” about risk management and other ways people are exposed to PFAS.
“The EPA acknowledges that PFAS is ubiquitous in the environment and eliminating all risks may not be feasible in the near term,” she said.
The federal agency is taking public comment on its draft through mid-March before releasing a final report that “will help inform the EPA’s potential future regulatory actions,” according to the draft report.
This story was originally published February 19, 2025 at 6:00 AM.
