TEWKSBURY — Test results are in for Tewksbury’s drinking water in the wake of revelations in November that runoff from a landfill in New Hampshire was being sent to Lowell’s Duck Island waste water treatment plant for processing and subsequent discharge into the Merrimack River. The water, discharged above Tewksbury’s raw water intake, raised concern with environmental groups due to the presence of PFAS, a class of chemical considered harmful to humans.
According to the lab report from Alpha Analytical of Westborough, Massachusetts sent to the town on Monday, Dec. 30, 2019, the raw water sample showed levels of PFOA/PFOS at 8.31 ng/L [nanogram per liter], and the PFAS (5 compounds total) at 8.31 ng/L. The finish water sample showed levels of PFOA/PFOS at 3.36 ng/L and PFAS (5 compounds total) at 3.36 ng/L.
According to DPW superintendent Brian Gilbert, these results are good news, since they are not as high in the river as anticipated and Tewksbury is well under the 20 ng/L limit that DEP intends to implement and enforce for finish water as they promulgate updated regulations.
However, Gilbert did offer the caveat that this is for one sample on one day, and that ongoing testing will be undertaken by the town.
Aligned with this issue, MassDEP is proposing to amend 310 CMR 22.00 Drinking Water regulations to establish a Total Per- and polyfluoroalkyl substances (PFAS) Maximum Contaminant Level (MCL) of 20 ppt [parts per trillion] for six PFAS contaminants: perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluoroheptanoic acid (PFHpA), and perfluorodecanoic acid (PFDA).
According to the EPA, this class of chemicals has been used in consumer products since the 1950s, but have become persistent in the environment. They are considered “forever chemicals” in that they do not break down. These chemicals also collect in the human body and are considered to have “adverse human health effects.”
Gilbert said that the town has budgeted for quarterly testing of these compounds in both the raw water and finish water product.
“This is a special kind of testing,” said Gilbert, explaining that the collector of the samples must follow strict protocols, including the type of clothing that can be worn and, for example, must be free of hand lotion or other products that could interfere with results.
Additionally, only certain labs are certified to test for the PFAS compounds. Gilbert is confident in Tewksbury’s water and credits the sand carbon filters for removing 60 percent of the compounds coming into the plant from raw to finish. Carbon filters rank among the best protections to capture the PFAS in the water, and Tewksbury has been using this method for years.
A public hearing by MassDEP to discuss the proposed new regulations will be held locally on Wednesday, Jan. 29, 2020 at 1 p.m. at MassDEP’s Northeast Regional Office, 205 Lowell St., Wilmington.
For more information, call (978) 694-3200. Comments about the changes may be submitted via email to Mass DEP Drinking Water Program at email@example.com.