MERRIMACK — The Saint-Gobain contamination zone now under investigation by the state has more than quadrupled in size.
With newer, more stringent state standards in place for perfluorooctanoic acid, or PFOA, thousands of additional private wells in the region will need to be tested for contamination, according to officials.
Previously, the New Hampshire Department of Environmental Services was investigating water contamination within a 14-square-mile area of the Saint-Gobain Performance Plastics facility in Merrimack.
“Now, we are currently investigating a 64-square-mile area,” Jeff Marts with DES’ Hazardous Waste Remediation Bureau told local residents this week.
Wells within the expanded area, which equates to about a 4.5-mile radius around the Saint-Gobain complex, have detected PFOA contamination above the 12 parts per trillion regulation. When the new PFOA standards were implemented a few weeks ago, Saint-Gobain submitted a work plan proposing that it sample water from an additional 360 private wells in the area, according to Marts.
DES, however, requested that more samples be taken and Saint-Gobain eventually agreed to add 224 more well samples, and later agreed to add an extra 360 wells. In total, the company will now test 944 more wells within the expanded 64-square-mile area from its plant, said Marts.
“Saint-Gobain has committed to targeting completion of the sampling program within a year,” he added.
Mike Wimsatt, director of DES’ Waste Management Division, said DES will continue to press Saint-Gobain to take action.
“We are sympathetic here. We do realize this is frustrating for people,” said Wimsatt.
Barbara Healey, town councilor, said that while much of the focus is on private wells, she said the public Merrimack Village District water supply is also showing PFOA above the 12 ppt regulation.
“When is Saint-Gobain going to provide bottled water for the entire town of Merrimack and the affected surrounding areas?” asked Healey.
Wimsatt said that if MVD water is not meeting the current standards, that treatment will be necessary. MVD is already in the process of installing treatment on two of its public wells that are now offline, and has plans to eventually filter all of its wells.
“The short answer is that I don’t think that bottled water for the users of the MVD system is going to be in the future,” Wimsatt said during a public hearing Tuesday in Merrimack.
According to Marts, more than 1,000 groundwater samples have already been analyzed for PFOA at and around the Saint-Gobain plant.
“Fifty-nine percent of the samples exceed the current ambient groundwater quality standard of 12 ppt for PFOA,” he said. “ … There are 25 different potential release areas (at Saint-Gobain) that are being investigated.”
Furthermore, Marts said there are different spill areas that have been identified that are also under investigation at the site, in addition to wells near Dumpling Brook that contain perfluorooctane sulfonate, or PFOS, and other areas of PFOS concentration on the rear, eastern side of the Saint-Gobain facility.
“Saint-Gobain continues to emit PFAS (per- and polyfluoroalkyl substances) as a part of their operating processes from their stacks,” said Bill Boyd, town councilor.
Although an air permit has been drafted, Boyd questioned whether it is acceptable for the town to have to wait more than a year for some of the stormwater issues to be addressed, especially since all of the groundwater wells at Saint-Gobain show contamination.
Since PFOA was discovered at the plant three years ago, 17 miles of public water lines have been installed and 930 properties have been connected to public water, according to Marts.
“We continue to work with the state to take action when needed and monitor where appropriate,” Lia LoBello, senior communications manager with Saint-Gobain, said in a recent statement.