At Fairfax Water, our top priority is providing you with safe, reliable drinking water. We follow the regulations set by the U.S. Environmental Protection Agency (EPA) under the Safe Drinking Water Act (SDWA) to make sure our water meets the highest standards. In 2024, Fairfax Water participated in EPA’s Fifth Unregulated Contaminant Monitoring Rule (UCMR5).
Under UCMR 5, utilities are required to monitor for a list of target chemicals in a 12-month period between January 2023 and December 2025. UCMR5 specifies monitoring for 29 per- and polyfluoroalkyl substances (PFAS) and lithium. These contaminants may be present in drinking water but are not yet subject to EPA drinking water standards. The purpose of monitoring for these contaminants is to provide EPA with data to help the agency determine if the contaminants should have a regulatory standard.
For more information on UCMR5, visit EPA’s UCMR web page (epa.gov/dwucmr) or call the Safe Drinking Water Hotline at 1-800-426-4791.
UCMR5 Monitoring Detects
Below is a list of the detected components from Fairfax Water’s UCMR5 monitoring. Lithium was one of the analytes included in UCMR5. No lithium was detected in the UCMR5 sampling. Click here to view the lithium data report. A full list of the PFAS components for UCMR5, including those that were not detected, can be found here.
Corbalis Treatment Plant Finished Water (Potomac 1)
|
Components (ppb) |
Average [1] |
Minimum |
Maximum |
Use or Environmental Source |
|---|---|---|---|---|
|
6:2 Fluorotelomer sulfonic acid (6:2 FTS) |
0.002 |
ND |
0.010 |
PFAS are a group of synthetic chemicals used in a wide range of consumer products and industrial applications including: non-stick cookware, water-repellent clothing, stain-resistant fabrics and carpets, cosmetics, firefighting foams, electroplating, and products that resist grease, water, and oil. PFAS are found in the blood of people and animals and in water, air, fish, and soil at locations across the United States and the world. |
|
Perfluorohexanoic acid (PFHxA) |
0.001 |
ND |
0.005 |
|
|
Perfluoropentanoic acid (PFPeA) |
0.001 |
ND |
0.005 |
[1] Average result calculated using a value of 0 for any results below the reporting level.
ND = non-detect (below reporting limit)
Griffith Treatment Plant Finished Water (Occoquan)
|
Components ( ppb) |
Average [1] |
Minimum |
Maximum |
Use or Environmental Source |
|---|---|---|---|---|
|
Perfluorobutanesulfonic acid (PFBS)[2] |
0.006 |
0.004 |
0.008 |
PFAS are a group of synthetic chemicals used in a wide range of consumer products and industrial applications including: non-stick cookware, water-repellent clothing, stain-resistant fabrics and carpets, cosmetics, firefighting foams, electroplating, and products that resist grease, water, and oil. PFAS are found in the blood of people and animals and in water, air, fish, and soil at locations across the United States and the world. |
|
Perfluorobutanoic acid (PFBA) |
0.011 |
ND |
0.018 |
|
|
Perfluoroheptanoic acid (PFHpA) |
0.004 |
ND |
0.006 |
|
|
Perfluorohexanoic acid (PFHxA) |
0.012 |
0.006 |
0.017 |
|
|
Perfluorooctanesulfonic acid (PFOS)[2] |
0.003 |
ND |
0.006 |
|
|
Perfluorooctanoic acid (PFOA)[2] |
0.005 |
ND |
0.007 |
|
|
Perfluoropentanoic acid (PFPeA) |
0.014 |
0.006 |
0.022 |
[1] Average result calculated using a value of 0 for any results below the reporting level.
ND = non-detect (below reporting limit)
[2] This component is included in EPA’s PFAS regulation, published in 2024. Water utilities are required to meet this regulation by 2029. To learn more about Fairfax Water’s PFAS monitoring visit fairfaxwater.org/water-quality/facts-about-pfas.
Washington Aqueduct Finished Water (Potomac 2)
|
Components ( ppb) |
Average [1] |
Minimum |
Maximum |
Use or Environmental Source |
|---|---|---|---|---|
|
Perfluorobutanesulfonic acid (PFBS)[2] |
0.001 |
ND |
0.003 |
PFAS are a group of synthetic chemicals used in a wide range of consumer products and industrial applications including: non-stick cookware, water-repellent clothing, stain-resistant fabrics and carpets, cosmetics, firefighting foams, electroplating, and products that resist grease, water, and oil. PFAS are found in the blood of people and animals and in water, air, fish, and soil at locations across the United States and the world. |
|
Perfluorohexanoic acid (PFHxA) |
0.001 |
ND |
0.004 |
|
|
Perfluoropentanoic acid (PFPeA) |
0.001 |
ND |
0.005 |
[1] Average result calculated using a value of 0 for any results below the reporting level.
ND = non-detect (below reporting limit)
[2] This component is included in EPA’s PFAS regulation, published in 2024. Water utilities are required to meet this regulation by 2029. To learn more about Fairfax Water’s PFAS monitoring visit fairfaxwater.org/water-quality/facts-about-pfas.