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Community PFAS Testing
Massachusetts Water Resources Authority

WILMINGTON

You might have seen recent news reports about per-and polyfluoroalkyl substances (together abbreviated as PFAS). This is a class of human-made chemicals typically associated with certain fire-fighting foams. These chemicals are persistent in the environment and have been used in products we all use for decades.

On October 2, 2020, MassDEP published the drinking water standard or maximum contaminant level (MCL) of 20 nanograms per liter (ng/L), or parts per trillion (ppt), for PFAS based on the sum of concentrations for six PFAS compounds. The six PFAS are: perfluorooctane sulfonic acid (PFOS); perfluorooctanoic acid (PFOA); perfluorohexane sulfonic acid (PFHxS); perfluorononanoic acid (PFNA); perfluoroheptanoic acid (PFHpA); and perfluorodecanoic acid (PFDA).

Wilmington conducted tests using extremely sensitive analystical methods for 14 different PFAS compounds using a MassDEP approved laboratory and methods in July 2019. Using test methods that can detect the presence of these chemicals down to levels below a part per trillion (ppt), we found evidence that some of these chemicals are in our water at low levels. We conducted confirmatory sampling on six of the compounds in August 2019, with similar results. The results are below the regulatory levels published by MassDEP for drinking water.

To review new information on PFAS test results in 2021 and 2022 for Wilmington’s drinking water, go to: https://www.wilmingtonma.gov/water-sewer-division/pages/pfas-wilmington.

2023 PFAS Test Results for Wilmington

Butters Row Treatment Plant
PFAS Analyte (results in ppt) 1/3/23 2/1/23 3/1/23 4/3/23 6/5/23 7/6/23 8/2/23**
Perfluorohexanesulfonic acid (PFHxS) ND ND ND ND ND ND 3.1
Perfluoroheptanoic acid (PFHpA) ND ND ND ND ND ND 5.45
Perfluorooctanoic acid (PFOA) ND ND ND ND ND Trace* 12
Perfluorooctanesulfonic acid (PFOS) ND ND ND ND ND ND 8.5
Perfluorononanoic acid (PFNA) ND ND ND ND ND ND Trace*
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND Trace*
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l ND ND ND ND ND ND 29.05

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
**PFAS results for 8/2023 are averages of duplicate samples for each PFAS.
MCL = Maximum Contaminant Level, highest level allowed
ND = Not Detected


Unregulated PFAS 1/3/23 2/1/23 3/1/23 4/3/23 6/5/23 7/6/23 8/2/23
PFBS ND ND ND ND Trace* 3 4.55
PFHxA ND ND ND ND Trace* 2.2 4.55
NEtFOSAA ND ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND ND
Adona ND ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND ND

Sargent Treatment Plant

PFAS Analyte (results in ppt) 1/3/23 2/1/23 3/1/23 4/3/23 6/5/23 7/14/23 8/2/23
Perfluorohexanesulfonic acid (PFHxS) ND 3.5 ND Trace* 2.1 2.5 Trace*
Perfluoroheptanoic acid (PFHpA) ND 4.4 Trace* Trace* 3.7 4.7 3
Perfluorooctanoic acid (PFOA) Trace* 11 2.4 2.1 6.7 8.9 5.4
Perfluorooctanesulfonic acid (PFOS) ND 6.7 Trace* Trace* 3.9 6.5 2.7
Perfluorononanoic acid (PFNA) ND Trace* ND ND Trace* Trace* ND
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND ND
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l ND 25.6 2.4 2.1 16.4 22.6 11.1

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
MCL = Maximum Contaminant Level, highest level allowed


Unregulated PFAS 1/3/23 2/1/23 3/1/23 4/3/23 6/5/23 7/14/23 8/2/23
PFBS ND 2.9 ND Trace* Trace* 2.4 2.5
PFHxA Trace* 7.3 ND 3.5 2.9 4.7 4.5
NEtFOSAA ND ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND ND
Adona ND ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND ND

2022 PFAS Test Results for Wilmington

Butters Row Treatment Plant
PFAS Analyte (results in ppt) 1/5/22 2/2/22 3/2/22 4/6/22 5/1/22 6/6/22
Perfluorohexanesulfonic acid (PFHxS) Trace* Trace* Trace* Trace* Trace* Trace*
Perfluoroheptanoic acid (PFHpA) Trace* 1.8 Trace* 1.8 2.1 2.5
Perfluorooctanoic acid (PFOA) 4.6 5 4.4 5.4 4.7 5.7
Perfluorooctanesulfonic acid (PFOS) Trace* 2.1 2.1 2.5 Trace* 2.9
Perfluorononanoic acid (PFNA) ND ND ND ND ND ND
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l 4.6 8.9 6.5 9.7 6.8 10.7

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
MCL = Maximum Contaminant Level, highest level allowed
ND = Not Detected

PFAS Analyte (results in ppt) 7/6/22 8/3/22 9/1/22 10/3/22 11/2/22 12/1/22
Perfluorohexanesulfonic acid (PFHxS) Trace* Trace* 2.2 ND ND ND
Perfluoroheptanoic acid (PFHpA) 2.5 2.9 3.0 ND Trace* ND
Perfluorooctanoic acid (PFOA) 6.1 6.9 9.2 ND 2 ND
Perfluorooctanesulfonic acid (PFOS) 2.5 3.1 4.1 ND Trace* ND
Perfluorononanoic acid (PFNA) ND ND ND ND ND ND
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l 11.1 12.9 18.5 0 2 0

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
MCL = Maximum Contaminant Level, highest level allowed


Unregulated PFAS 1/5/22 2/2/22 3/2/22 4/6/22 5/1/22 6/6/22
PFBS 4.5 5.1 4.2 4 3.3 3.2
PFHxA 3.8 3.7 4.2 3.5 4 4
NEtFOSAA ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND
Adona ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND
Unregulated PFAS 7/6/22 8/3/22 9/1/22 10/3/22 11/2/22 12/1/22
PFBS 2.9 5.3 12 1.8 5.8 ND
PFHxA 5.6 5.3 5.8 ND Trace* ND
NEtFOSAA ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND
Adona ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND

Sargent Treatment Plant

PFAS Analyte (results in ppt) 1/5/22 2/2/22 3/2/22 4/6/22 5/1/22 6/6/22
Perfluorohexanesulfonic acid (PFHxS) ND ND ND ND Trace* Trace*
Perfluoroheptanoic acid (PFHpA) ND ND Trace* Trace* Trace* 2
Perfluorooctanoic acid (PFOA) Trace* Trace* Trace* 2.4 3 4.3
Perfluorooctanesulfonic acid (PFOS) ND ND ND Trace* Trace* Trace*
Perfluorononanoic acid (PFNA) ND ND ND ND ND ND
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l 0 0 0 2.4 3 6.3

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
MCL = Maximum Contaminant Level, highest level allowed

PFAS Analyte (results in ppt) 7/6/22 8/3/22 9/1/22 10/3/22 11/2/22 12/1/22
Perfluorohexanesulfonic acid (PFHxS) Trace* Trace* Trace* ND Trace* ND
Perfluoroheptanoic acid (PFHpA) 2.4 2.8 2.4 Trace* Trace* ND
Perfluorooctanoic acid (PFOA) 6.1 5.5 6.3 2.6 2.4 ND
Perfluorooctanesulfonic acid (PFOS) 2.1 2.4 2.4 ND Trace* ND
Perfluorononanoic acid (PFNA) ND ND ND ND ND ND
Perfluorodecanoic acid (PFDA) ND ND ND ND ND ND
Sum of PFAS6 - compare to MassDEP MCL of 20 ng/l 10.6 10.7 11.1 2.6 2.4 ND

* Trace amounts are present but they are below the minimum concentration that can be reported as a quantified value. Categorized as not detected by MassDEP.
MCL = Maximum Contaminant Level, highest level allowed


Unregulated PFAS 1/5/22 2/2/22 3/2/22 4/6/22 5/1/22 6/6/22
PFBS ND Trace* Trace* Trace* Trace* 2.1
PFHxA ND Trace* 2.6 2.7 3.6 4.4
NEtFOSAA ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND
Adona ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND
Unregulated PFAS 7/6/22 8/3/22 9/1/22 10/3/22 11/2/22 12/1/22
PFBS 2.1 2.9 2 Trace* Trace* ND
PFHxA 6.2 5.8 5.1 2 2.6 Trace*
NEtFOSAA ND ND ND ND ND ND
NMeFOSAA ND ND ND ND ND ND
PFDoA ND ND ND ND ND ND
PFTeDA ND ND ND ND ND ND
PFTrDA ND ND ND ND ND ND
PFUnA ND ND ND ND ND ND
11Cl-PF3OUdS ND ND ND ND ND ND
9Cl-PF3ONS ND ND ND ND ND ND
Adona ND ND ND ND ND ND
HFPO-DA ND ND ND ND ND ND

2019 PFAS Test Results for Peabody

PFAS Analyte (results in ppt) Sargent Treatment Plant - 7/15/19 Sargent Treatment Plant - 8/12/19
Perfluorohexanesulfonic acid (PFHxS) Not Detected Not Detected
Perfluoroheptanoic acid (PFHpA) Not Detected Not Detected
Perfluorooctanoic acid (PFOA) 1.3 3.3
Perfluorooctanesulfonic acid (PFOS) Not Detected Not Detected
Perfluorononanoic acid (PFNA) Not Detected Not Detected
Perfluorodecanoic acid (PFDA) Not Detected Not Detected
Compare to proposed MassDEP standard of 20 ppt for the sum of these six compounds* 1.3 3.3

* MassDEP has proposed a drinking water standard of 20 ppt for the sum of these six compounds. The sum reported here is based on the proposed MassDEP approach for handling trace results detected below laboratory reporting levels.


 
PFBS Not Detected Not Tested
PFHxA Not Detected Not Tested
NEtFOSAA Not Detected Not Tested
NMeFOSAA Not Detected Not Tested
PFDoA Not Detected Not Tested
PFTeDA Not Detected Not Tested
PFTrDA Not Detected Not Tested
PFUnA Not Detected Not Tested

   
Information on MWRA PFAS Levels

 
Historic Withdrawls Reservoir Levels