The state has ordered the Saint Gobain plastics manufacturer to install air pollution controls on its Merrimack factory.
The facility’s smokestacks are thought to be the source of high levels of PFAS chemicals that contaminated nearby drinking water wells two years ago.
Tests of the stacks since then show Saint Gobain may still be emitting low levels of the chemicals.
Now, the state will hold the factory to a newly passed law regulating soil and water pollution from air emissions.
Officials told the company Monday to apply for an air pollution permit and submit an analysis of the systems they might use within six months.
The state will bring residents up to speed on the issue at a public meeting in Merrimack on October 10th.