The Merrimack warehouse that U.S. Immigration and Customs Enforcement plans to turn into an immigrant detention facility sits within a contamination zone where residents have long faced issues with chemical pollution in their drinking water.
Located at 50 Robert Milligan Parkway, the site is in the southwestern corner of a roughly 65-square-mile area in Merrimack where state officials have investigated man-made PFAS chemicals in soil and water. Those so-called “forever chemicals” are linked to a variety of illnesses, including some cancers.
New Hampshire state officials attribute that contamination to fabric coating operations at the former Saint-Gobain Performance Plastics manufacturing plant. The now-demolished facility is located roughly six miles from the proposed ICE detention center. While the facility is gone, the chemicals it left behind continue to linger in communities surrounding the plant. PFAS chemicals are known for not breaking down easily in the environment.
The Centers for Disease Control and Prevention say people can be exposed to PFAS chemicals by breathing, eating, drinking, or touching a chemical. People who live near sites with contaminated air, soil or drinking water are at risk of being exposed.
The proposed ICE facility has ignited intense pushback from residents and local officials, who have said repeatedly they are in the dark about any plans by the federal government. On Feb. 17, the town posted a notice to its website responding to what it said were zoning related inquiries about the property, which falls within the town’s industrial zone.
“If it's not spelled out in the zoning ordinances, then it's not permitted,” said Merrimack town manager Paul Micali. He said the town is at a “crossroads” on how to proceed, given that it is unclear whether the federal government plans to lease or purchase the warehouse.
Other communities around the country that also have had proposed ICE detention centers have said federal agencies can typically supersede local zoning ordinances.
Gov. Kelly Ayotte has said federal officials should consult with local leaders about their plans for the site, but she has not yet herself come out publicly against or in favor of the facility.
The planned Merrimack facility is one of a number of detention centers where ICE is hoping to expand its detention capacity nationwide. Some detention facilities in other states have been located near toxins. In Texas, the Karnes County Residential Center is within 100 feet of gas flares and oil wells. In Tacoma, Washington, a facility sits next to a federal Superfund site contaminated with sludge from a coal gasification plant.
Potential water impacts
Private wells within the contamination zone in Merrimack have tested at high levels for PFAS chemicals, while local public water utilities have taken on testing and treatment efforts to filter those chemicals out. The potential detention facility receives water from Pennichuck Water Works, according to the Merrimack Village District, the water utility for the town of Merrimack.
Pennichuck is a public water utility company serving several communities in the area and is required to comply with state standards that limit the amount of several PFAS chemicals allowed in drinking water. Private wells are not required to comply with state standards, though state regulators recommend all private well owners have their water tested.
A document from Immigrations and Customs Enforcement says an engineering assessment at the Merrimack site reviewed “additional capacities for domestic water supply” at the facility and concluded the site would have sufficient ability to support a new detention facility.
Rep. Bill Boyd, a Republican state lawmaker from Merrimack, noted his concern about the impact of a new detention facility on the town’s Aquifer Conservation District in a letter to Trammell Crow, the company that owns the warehouse.
Testing of a groundwater sample from a well near the warehouse next to the Everett Turnpike in 2021 found PFOA present at 109 parts per trillion. That’s far higher than the state standard for PFOA in drinking water of 12 parts per trillion.
Potential soil impacts
PFAS chemicals have been found in soil around the former Saint-Gobain manufacturing plant, and soils at the site itself have been “grossly impacted,” according to state regulators.
State officials have two kinds of standards for how much PFAS can be in soil.
The direct contact recommendations are meant to protect people who are directly exposed to soil. That recommendation varies based on the kind of contact (for example, contact by construction workers, outdoor maintenance workers, or young children who may be exposed while playing in soil). Accidentally swallowing soil or dust is more of a risk than getting the soil on your skin.
Another limit, known as a remediation standard, is meant to protect groundwater and drinking water from becoming more contaminated as chemicals leach from soil into water. Those standards are lower than the standards for direct contact.
There are no rules that would require soil sampling when a property changes uses, according to the New Hampshire Department of Environmental Services.
Regulators have tested more water than soil within the contamination zone, but testing from a Department of Transportation project in 2021 showed some samples taken near the Everett Turnpike had levels of PFOA in their soil above state remediation standards.
In September 2025, New Hampshire regulators asked Saint-Gobain to conduct more soil sampling in the contamination zone. The company agreed to update a 2020 soil sampling plan that was not completed. That plan is expected to be submitted in early 2026.
