12-06-2025
Group claims wastewater permit would let Manchester dump PFAS into Merrimack River
The Conservation Law Foundation (CLF) is arguing that the state's approval of a permit allows the Manchester Wastewater Treatment Facility to discharge toxic chemicals into the Merrimack River.
An appeal filed Thursday with the New Hampshire Water Council claims the New Hampshire Department of Environmental Services approved the Manchester facility's National Pollutant Discharge Elimination System permit renewal on May 13 without evaluating or determining whether 'in light of discharges and emissions of per- and polyfluoroalkyl substances (PFAS) from the Manchester WWTF' the treatment facility's permitted activities will comply with New Hampshire's water quality standard for toxic substances and the Merrimack River's designated use for fish consumption.
Merrimack River
The Merrimack River in Manchester
'People deserve safe, clean water, and state regulators have a critical role to ensure that's what we have in New Hampshire,' Tom Irwin, the Conservation Law Foundation (CLF)'s vice president for New Hampshire, said in statement. 'By failing to consider whether PFAS chemicals are violating important safeguards intended to protect water and people from toxic pollutants, regulators are putting our environment and health at risk.'
A request for comment from Manchester officials was not immediately returned Thursday.
PFAS chemicals, known as "forever chemicals" because they do not break down in the environment or in human bodies, have been linked to several health problems like cancer; fertility issues; child-development disorders; hormonal dysfunction; and damage to the thyroid, kidney and liver.
CLF says the chemicals are found in wastewater from industrial users sent to Manchester's treatment facility, the largest such plant in northern New England and the only one in New Hampshire that incinerates its sewage sludge.
CLF's appeal argues the state agency failed to evaluate whether releases of PFAS chemicals from the facility — both in wastewater discharged into the Merrimack River, and emitted into the air from the facility's sludge-burning incinerator — violate water quality standards, including regulations aimed at protecting people who consume fish.
In its appeal, CLF claims that the WWTF discharges 'treated' wastewater into the Merrimack River but the WWTF's treatment process does not address or remove PFAS.
Manchester wastewater treatment plant stack
The air emissions pipe from the Manchester wastewater treatment plant, as seen from Gay Street.
'The WWTF has detected PFAS in its influent and 'treated' effluent (wastewater) on a monthly basis since at least 2019,' the appeal says. 'In addition to discharging PFAS into the Merrimack River through wastewater discharges, the WWTF releases PFAS into the air through sludge incineration, as confirmed by data published in a peer-reviewed study in 2023 (the Seay Study).'
The Manchester facility receives wastewater from at least 88 industrial users, 14 of which (including the city's closed landfill) are classified as Significant Industrial Users under EPA and local rules, the appeal says.
'The City of Manchester applied for a new (National Pollutant Discharge Elimination System) permit in 2019 and, in that application, did not disclose that its discharges contain PFAS,' the appeal says.
When waste departs industrial sites in Manchester or surrounding communities like Bedford and Londonderry, it eventually winds up in the city's wastewater treatment facility, where a strainer removes debris. Solids settle at the bottom of a chamber until burned or put in a landfill, and bacteria eat any organic matter in the mix. The water is chlorinated, de-chlorinated, and put back into the Merrimack River.
Leachate, a liquid found at landfill sites, is also handled at the Manchester facility.
During the permit renewal process, CLF lawyers sent comments to the Department of Environmental Services in June 2024 that sources of PFAS — like wastewater treatment plants, landfills and manufacturing facilities — often disproportionately impact communities of color due to inequitable siting.
'Two U.S. Census Tracts that are located roughly two miles away from the WWTF and its incinerator are overburdened by environmental pollution,' the CLF wrote. 'One of these communities has a population that is 56 percent people of color, 62 percent low income ... another has a population that is 41 percent people of color, 43 percent low income. These two communities are located north and northeast of the facility, exposing them to health risks from breathing contaminated air when wind blows from the south.
'Manchester residents that fish near or downstream of the WWTF are also likely disproportionately impacted by the WWTF's PFAS pollution in water and air.'
CLF lawyers claim PFAS pollution from the WWTF also threatens the health of residents in downstream communities that source their drinking water from the Merrimack River.
