- PWSID
- VA6059501
- State
- Virginia
- System type
- community water system (CWS)
- Population served
- 1,121,613
- City
- Herndon
- Counties
- Fairfax County, Fairfax city, Falls Church city
- Primary source water
- surface water
- UCMR 5 sampling
- 2024-03-26 to 2025-02-13 · 6 entry point(s) · water types: SW
- Service-area boundary
- authoritative
PFOA 1–3 × its limit highest single result
PFOA 1–3 × its limit worst entry-point average
Open on the Virginia map · All Virginia systems · All results
These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.
Water purchased from
- Washington Aqueduct Division. (DC0000001)
Seller not monitored under UCMR 5.
Seller results are the seller's own entry-point samples, not measurements of this system's water. This system's own samples (below) may reflect purchased water, its own sources, or both.
Compared with EPA's 2024 values
| Highest single result | Worst entry-point average* | Limit | |
|---|---|---|---|
| PFOA (ppt) | 7.4 | 4.62 | 4 |
| PFOS (ppt) | 5.7 | 2.6 | 4 |
| Hazard Index | 0.004 | 0.003 | 1.0† |
“<MRL” = every result for the compound was below its reporting limit. * Mean of all samples at each entry point with non-detects = 0 (EPA compliance convention; the Hazard Index also uses non-detects = 0); a screening comparison, not a formal running annual average. † Rescission proposed May 2026. PFOA/PFOS MCL 4 ppt (2024 NPDWR, in effect). PFHxS, PFNA, HFPO-DA (10 ppt each) and the Hazard Index (1.0) are 2024 NPDWR values; EPA proposed rescinding them on 18 May 2026 (comment period closed 20 Jul 2026).
No Virginia PFAS drinking-water standard in effect or proposed as of 2026-10-17: No Virginia-specific PFAS drinking-water MCL; Va. Code 62.1-44.34:29 defines PFAS MCL by reference to EPA's NPDWR.
Sampling history
Sampled 2024-03-26 to 2025-02-13 · 6 entry point(s) · water types: SW · 35 sampling visits. PFAS in ppt (ng/L).
| Date | Entry point | Event | PFOA | PFOS | HI | Other detections |
|---|---|---|---|---|---|---|
| 2024-03-26 | CHAIN BRIDGE ENTRY POINT (SW) | SE1 | <4 | <4 | 0 | none |
| 2024-03-26 | Corbalis WTP (SW) | SE1 | n/a | n/a | n/a | none |
| 2024-03-26 | Corbalis WTP (SW) | SE1 | n/a | n/a | n/a | none |
| 2024-03-26 | Corbalis WTP (SW) | SE1 | n/a | n/a | n/a | none |
| 2024-03-26 | Corbalis WTP (SW) | SE1 | n/a | n/a | n/a | none |
| 2024-03-26 | Griffith WTP (SW) | SE1 | n/a | n/a | n/a | none |
| 2024-04-23 | Corbalis WTP (SW) | SE1 | <4 | <4 | 0 | 6:2 FTS 9.2, PFHxA 4.3, PFPeA 4.7 |
| 2024-04-23 | Corbalis WTP (SW) | SE1 | <4 | <4 | 0 | 6:2 FTS 10.1, PFHxA 4.5, PFPeA 4.2 |
| 2024-04-23 | Corbalis WTP (SW) | SE1 | <4 | <4 | 0 | 6:2 FTS 9.1, PFHxA 4.1, PFPeA 4.2 |
| 2024-04-23 | Corbalis WTP (SW) | SE1 | <4 | <4 | 0 | 6:2 FTS 9.6, PFHxA 4.3, PFPeA 4.4 |
| 2024-04-23 | Griffith WTP (SW) | SE1 | <4 | <4 | 0.002 | PFHxA 5.7, PFPeA 6.3 |
| 2024-06-11 | CHAIN BRIDGE ENTRY POINT (SW) | SE2 | <4 | <4 | 0 | none |
| 2024-06-11 | Corbalis WTP (SW) | SE2 | <4 | <4 | 0 | none |
| 2024-06-11 | Corbalis WTP (SW) | SE2 | <4 | <4 | 0 | none |
| 2024-06-11 | Corbalis WTP (SW) | SE2 | <4 | <4 | 0 | none |
| 2024-06-11 | Corbalis WTP (SW) | SE2 | <4 | <4 | 0 | none |
| 2024-06-11 | Griffith WTP (SW) | SE2 | 5 | 4.7 | 0.003 | PFBA 9.6, PFHpA 3.9, PFHxA 9.6, PFPeA 10.7 |
| 2024-09-10 | CHAIN BRIDGE ENTRY POINT (SW) | SE3 | <4 | <4 | 0.002 | PFHxA 4, PFPeA 4.8 |
| 2024-09-10 | Corbalis WTP (SW) | SE3 | <4 | <4 | 0 | none |
| 2024-09-10 | Corbalis WTP (SW) | SE3 | <4 | <4 | 0 | none |
| 2024-09-10 | Corbalis WTP (SW) | SE3 | <4 | <4 | 0 | none |
| 2024-09-10 | Corbalis WTP (SW) | SE3 | n/a | n/a | n/a | none |
| 2024-09-10 | Griffith WTP (SW) | SE3 | 7.4 | 5.7 | 0.004 | PFBA 17.5, PFHpA 5.6, PFHxA 17.1, PFPeA 21.5 |
| 2024-09-30 | Corbalis WTP (SW) | SE3 | <4 | <4 | 0 | PFHxA 3, PFPeA 3.2 |
| 2024-12-17 | CHAIN BRIDGE ENTRY POINT (SW) | SE4 | n/a | n/a | n/a | none |
| 2024-12-17 | Corbalis WTP (SW) | SE4 | n/a | n/a | n/a | none |
| 2024-12-17 | Corbalis WTP (SW) | SE4 | n/a | n/a | n/a | none |
| 2024-12-17 | Corbalis WTP (SW) | SE4 | n/a | n/a | n/a | none |
| 2024-12-17 | Corbalis WTP (SW) | SE4 | n/a | n/a | n/a | none |
| 2024-12-17 | Griffith WTP (SW) | SE4 | 6.1 | <4 | 0.004 | PFBA 17.6, PFHpA 4.9, PFHxA 13.6, PFPeA 17.7 |
| 2025-02-13 | CHAIN BRIDGE ENTRY POINT (SW) | SE4 | <4 | <4 | 0 | none |
| 2025-02-13 | Corbalis WTP (SW) | SE4 | <4 | <4 | 0 | none |
| 2025-02-13 | Corbalis WTP (SW) | SE4 | <4 | <4 | 0 | none |
| 2025-02-13 | Corbalis WTP (SW) | SE4 | <4 | <4 | 0 | none |
| 2025-02-13 | Corbalis WTP (SW) | SE4 | <4 | <4 | 0 | none |
“<4” = not detected at the reporting limit shown; “n/a” = not analyzed in that sample. Highlighted = at or above the 4 ppt MCL. HI computed per sample with non-detects as 0. Other detections lists every other quantified compound (lithium in µg/L).
All results by entry point
720 results. Each column is one sampling visit (date and UCMR 5 sample event). A number is a measured concentration; “< 4” = below the minimum reporting level shown; “–” = not analyzed in that visit. PFAS in ppt (ng/L); lithium in µg/L.
CHAIN BRIDGE ENTRY POINT facility 36886 · sample point EP401 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-12-17 SE4 | 2025-02-13 SE4 |
|---|---|---|---|---|---|---|
| PFBS | 3 ppt | < 3 | < 3 | 3.4 | – | < 3 |
| PFHxA | 3 ppt | < 3 | < 3 | 4 | – | < 3 |
| PFPeA | 3 ppt | < 3 | < 3 | 4.8 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | < 5 | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| 6:2 FTS | 5 ppt | < 5 | < 5 | < 5 | – | < 5 |
| 8:2 FTS | 5 ppt | < 5 | < 5 | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | < 2 | < 2 | – | < 2 |
| ADONA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | < 5 | < 5 | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 | < 5 | < 5 | – |
| NFDHA | 20 ppt | < 20 | < 20 | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 | < 6 | < 6 | – |
| PFBA | 5 ppt | < 5 | < 5 | < 5 | – | < 5 |
| PFDA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFDoA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFEESA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFHpA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFHpS | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 | < 3 | – | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 | < 4 | – | < 4 |
| PFNA | 4 ppt | < 4 | < 4 | < 4 | – | < 4 |
| PFOA | 4 ppt | < 4 | < 4 | < 4 | – | < 4 |
| PFOS | 4 ppt | < 4 | < 4 | < 4 | – | < 4 |
| PFPeS | 4 ppt | < 4 | < 4 | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | < 8 | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | < 7 | < 7 | < 7 | – |
| PFUnA | 2 ppt | < 2 | < 2 | < 2 | – | < 2 |
| lithium | 9 µg/L | < 9 | < 9 | < 9 | < 9 | – |
Corbalis WTP facility 93001 · sample point EP001 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-04-23 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-09-30 SE3 | 2024-12-17 SE4 | 2025-02-13 SE4 |
|---|---|---|---|---|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 9.2 | < 5 | – | < 5 | – | < 5 |
| PFHxA | 3 ppt | – | 4.3 | < 3 | – | 3 | – | < 3 |
| PFPeA | 3 ppt | – | 4.7 | < 3 | – | 3.2 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 | < 5 | – | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 | < 5 | – | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 | < 2 | – | < 2 | – | < 2 |
| ADONA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 | < 5 | – | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | – | < 5 | < 5 | – | < 5 | – |
| NFDHA | 20 ppt | – | < 20 | < 20 | – | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | – | < 6 | < 6 | – | < 6 | – |
| PFBA | 5 ppt | – | < 5 | < 5 | – | < 5 | – | < 5 |
| PFBS | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFDA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFDoA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFEESA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFHpA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFHpS | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 | – | < 3 | – | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 | – | < 4 | – | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 | – | < 4 | – | < 4 |
| PFOA | 4 ppt | – | < 4 | < 4 | – | < 4 | – | < 4 |
| PFOS | 4 ppt | – | < 4 | < 4 | – | < 4 | – | < 4 |
| PFPeS | 4 ppt | – | < 4 | < 4 | – | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | – | < 8 | < 8 | – | < 8 | – |
| PFTrDA | 7 ppt | < 7 | – | < 7 | < 7 | – | < 7 | – |
| PFUnA | 2 ppt | – | < 2 | < 2 | – | < 2 | – | < 2 |
| lithium | 9 µg/L | < 9 | – | < 9 | < 9 | – | < 9 | – |
Corbalis WTP facility 93001 · sample point EP002 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-04-23 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-12-17 SE4 | 2025-02-13 SE4 |
|---|---|---|---|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 10.1 | < 5 | < 5 | – | < 5 |
| PFHxA | 3 ppt | – | 4.5 | < 3 | < 3 | – | < 3 |
| PFPeA | 3 ppt | – | 4.2 | < 3 | < 3 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| ADONA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | – | < 5 | < 5 | < 5 | – |
| NFDHA | 20 ppt | – | < 20 | < 20 | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | – | < 6 | < 6 | < 6 | – |
| PFBA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| PFBS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDoA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFEESA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFPeS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | – | < 8 | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | – | < 7 | < 7 | < 7 | – |
| PFUnA | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| lithium | 9 µg/L | < 9 | – | < 9 | < 9 | < 9 | – |
Corbalis WTP facility 93001 · sample point EP003 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-04-23 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-12-17 SE4 | 2025-02-13 SE4 |
|---|---|---|---|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 9.1 | < 5 | < 5 | – | < 5 |
| PFHxA | 3 ppt | – | 4.1 | < 3 | < 3 | – | < 3 |
| PFPeA | 3 ppt | – | 4.2 | < 3 | < 3 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| ADONA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | – | < 5 | < 5 | < 5 | – |
| NFDHA | 20 ppt | – | < 20 | < 20 | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | – | < 6 | < 6 | < 6 | – |
| PFBA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| PFBS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDoA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFEESA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFPeS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | – | < 8 | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | – | < 7 | < 7 | < 7 | – |
| PFUnA | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| lithium | 9 µg/L | < 9 | – | < 9 | < 9 | < 9 | – |
Corbalis WTP facility 93001 · sample point EP004 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-04-23 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-12-17 SE4 | 2025-02-13 SE4 |
|---|---|---|---|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 9.6 | < 5 | < 5 | – | < 5 |
| PFHxA | 3 ppt | – | 4.3 | < 3 | < 3 | – | < 3 |
| PFPeA | 3 ppt | – | 4.4 | < 3 | < 3 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| ADONA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | – | < 5 | < 5 | < 5 | – |
| NFDHA | 20 ppt | – | < 20 | < 20 | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | – | < 6 | < 6 | < 6 | – |
| PFBA | 5 ppt | – | < 5 | < 5 | < 5 | – | < 5 |
| PFBS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFDoA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFEESA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHpS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 | < 3 | – | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOA | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFOS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFPeS | 4 ppt | – | < 4 | < 4 | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | – | < 8 | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | – | < 7 | < 7 | < 7 | – |
| PFUnA | 2 ppt | – | < 2 | < 2 | < 2 | – | < 2 |
| lithium | 9 µg/L | < 9 | – | < 9 | < 9 | < 9 | – |
Griffith WTP facility 93022 · sample point EP022 · surface water
| Compound | MRL | 2024-03-26 SE1 | 2024-04-23 SE1 | 2024-06-11 SE2 | 2024-09-10 SE3 | 2024-12-17 SE4 |
|---|---|---|---|---|---|---|
| PFBA | 5 ppt | – | < 5 | 9.6 | 17.5 | 17.6 |
| PFBS | 3 ppt | – | 3.6 | 5.1 | 8.1 | 7 |
| PFHpA | 3 ppt | – | < 3 | 3.9 | 5.6 | 4.9 |
| PFHxA | 3 ppt | – | 5.7 | 9.6 | 17.1 | 13.6 |
| PFOA | 4 ppt | – | < 4 | 5 | 7.4 | 6.1 |
| PFOS | 4 ppt | – | < 4 | 4.7 | 5.7 | < 4 |
| PFPeA | 3 ppt | – | 6.3 | 10.7 | 21.5 | 17.7 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 | < 5 | < 5 | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| 6:2 FTS | 5 ppt | – | < 5 | < 5 | < 5 | < 5 |
| 8:2 FTS | 5 ppt | – | < 5 | < 5 | < 5 | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 | < 2 | < 2 | < 2 |
| ADONA | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| HFPO-DA | 5 ppt | – | < 5 | < 5 | < 5 | < 5 |
| NEtFOSAA | 5 ppt | < 5 | – | < 5 | < 5 | < 5 |
| NFDHA | 20 ppt | – | < 20 | < 20 | < 20 | < 20 |
| NMeFOSAA | 6 ppt | < 6 | – | < 6 | < 6 | < 6 |
| PFDA | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFDoA | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFEESA | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFHpS | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 | < 3 | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 | < 4 | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 | < 4 | < 4 |
| PFPeS | 4 ppt | – | < 4 | < 4 | < 4 | < 4 |
| PFTA | 8 ppt | < 8 | – | < 8 | < 8 | < 8 |
| PFTrDA | 7 ppt | < 7 | – | < 7 | < 7 | < 7 |
| PFUnA | 2 ppt | – | < 2 | < 2 | < 2 | < 2 |
| lithium | 9 µg/L | < 9 | – | < 9 | < 9 | < 9 |
Statistics by compound
| Compound | Results | Detected | Highest (date) | Mean bounds | KM median | P75 | P90 | P95 |
|---|---|---|---|---|---|---|---|---|
| PFHxA | 24 | 42% | 17.1 2024-09-10 | 2.92–4.67 | <MRL | 4.3 | 9.6 | 13.6 |
| PFPeA | 24 | 42% | 21.5 2024-09-10 | 3.4–5.15 | <MRL | 4.4 | 10.7 | 17.7 |
| PFBS | 24 | 21% | 8.1 2024-09-10 | 1.13–3.51 | <MRL | <MRL | 5.1 | 7 |
| 6:2 FTS | 24 | 17% | 10.1 2024-04-23 | 1.58–5.75 | <MRL | <MRL | 9.2 | 9.6 |
| PFBA | 24 | 12% | 17.6 2024-12-17 | 1.86–6.24 | <MRL | <MRL | 9.6 | 17.5 |
| PFHpA | 24 | 12% | 5.6 2024-09-10 | 0.6–3.23 | <MRL | <MRL | 3.9 | 4.9 |
| PFOA | 24 | 12% | 7.4 2024-09-10 | 0.77–4.27 | <MRL | <MRL | 5 | 6.1 |
| PFOS | 24 | 8% | 5.7 2024-09-10 | 0.43–4.1 | <MRL | <MRL | <MRL | 4.7 |
Never detected (22): 11Cl-PF3OUdS, 4:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFDA, PFDoA, PFEESA, PFHpS, PFHxS, PFMBA, PFMPA, PFNA, PFPeS, PFTA, PFTrDA, PFUnA, lithium.
Left-censored Kaplan–Meier statistics (Helsel 2005; Helsel & Lee 2006, NADA for R). Units: ppt; lithium µg/L. Each compound has one reporting limit, so the Kaplan–Meier mean equals the upper mean bound (non-detects at the MRL); the lower bound sets non-detects to 0. “<MRL” = the percentile falls below the reporting limit and cannot be estimated. These describe this system's UCMR 5 samples, not population estimates.
Sources
- EPA UCMR 5 occurrence data text files (UCMR5_All.txt; samples 2023-01-10 to 2026-03-04; data summary dated Jul 2026)
- EPA SDWIS via ECHO SDWA downloads, quarter 2026Q3
- EPA Public Water System Service Areas v3 (Mar 2026)
- US Census Bureau cartographic boundary counties 1:500k, 2024
- EPA/USGS NHDPlus V2 (medium resolution) flowlines, Strahler order 2+
Data build c525414e2fcb · 2026-10-18T04:06Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.