- PWSID
- AZ0407046
- State
- Arizona
- System type
- community water system (CWS)
- Population served
- 57,070
- City
- Litchfield Park
- Counties
- Maricopa County
- Primary source water
- groundwater
- UCMR 5 sampling
- 2023-09-13 to 2024-04-16 · 7 entry point(s) · water types: GW
- Service-area boundary
- authoritative
PFOS ≥ 3 × its limit highest single result
PFOS 1–3 × its limit worst entry-point average
Open on the Arizona map · All Arizona 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.
Compared with EPA's 2024 values
| Highest single result | Worst entry-point average* | Limit | |
|---|---|---|---|
| PFOA (ppt) | 10.2 | 10.2 | 4 |
| PFOS (ppt) | 14.1 | 11.8 | 4 |
| Hazard Index | 1.893 | 1.361 | 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 Arizona PFAS drinking-water standard in effect or proposed as of 2026-10-17: No Arizona-specific PFAS drinking-water standard; ADEQ adopts federal drinking-water rules by reference (A.A.C. Title 18, Ch. 4).
Sampling history
Sampled 2023-09-13 to 2024-04-16 · 7 entry point(s) · water types: GW · 17 sampling visits. PFAS in ppt (ng/L).
| Date | Entry point | Event | PFOA | PFOS | HI | Other detections |
|---|---|---|---|---|---|---|
| 2023-09-13 | Airline Reservoir (GW) | SE1 | 10.2 | 11.2 | 0.703 | PFHpA 3.3, PFHxA 7.8, PFPeA 12.2, lithium 88.5 µg/L |
| 2023-09-13 | Townwell Reservoir (GW) | SE1 | 5 | <4 | 0.59 | PFHxA 3.4, lithium 85.7 µg/L |
| 2023-09-13 | Well 10 Airline (GW) | SE1 | <4 | 8.5 | 0.56 | PFBA 8.2, PFPeA 3.2, lithium 67.8 µg/L |
| 2023-09-13 | Well 2 Airline (GW) | SE1 | 5.9 | 7.8 | 0.794 | PFBA 20.3, PFHpA 6.1, PFHxA 23.2, PFPeA 54.6, lithium 74.6 µg/L |
| 2023-09-13 | Well 20-B (GW) | SE1 | 4.1 | 4.5 | 0.46 | PFHxA 4.4, PFPeA 6.6, lithium 111 µg/L |
| 2023-09-13 | Well 34-C (GW) | SE1 | <4 | 4.4 | 0.482 | lithium 92.2 µg/L |
| 2023-09-13 | Well Marbella 1 (GW) | SE1 | 5.6 | 14.1 | 1.893 | PFHpA 3.4, PFHxA 7.2, PFPeA 7.8, lithium 99.9 µg/L |
| 2024-03-20 | Airline Reservoir (GW) | SE2 | 10.2 | 12.4 | 0.803 | PFHpA 3.7, PFHxA 8, PFPeA 12.5, lithium 76 µg/L |
| 2024-03-20 | Townwell Reservoir (GW) | SE2 | 4.1 | <4 | 0.5 | lithium 72.7 µg/L |
| 2024-03-20 | Well 10 Airline (GW) | SE2 | <4 | 12 | 0.82 | PFBA 10, PFHxA 4, PFPeA 9.7, lithium 102 µg/L |
| 2024-03-20 | Well 2 Airline (GW) | SE2 | n/a | n/a | n/a | lithium 77.6 µg/L |
| 2024-03-20 | Well 20-B (GW) | SE2 | n/a | n/a | n/a | lithium 77.3 µg/L |
| 2024-03-20 | Well 34-C (GW) | SE2 | <4 | 5 | 0.413 | lithium 86.4 µg/L |
| 2024-03-21 | Well Marbella 1 (GW) | SE2 | n/a | n/a | n/a | lithium 166 µg/L |
| 2024-04-03 | Well 20-B (GW) | SE2 | 6.7 | 7.5 | 0.872 | PFHpA 3.4, PFHxA 9.1, PFPeA 9.6 |
| 2024-04-16 | Well 2 Airline (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-04-16 | Well Marbella 1 (GW) | SE2 | <4 | <4 | 0.83 | PFHxA 3 |
“<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
420 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.
Airline Reservoir facility 90003 · sample point POE003 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 |
|---|---|---|---|
| PFBS | 3 ppt | 5.2 | 5.8 |
| PFHpA | 3 ppt | 3.3 | 3.7 |
| PFHxA | 3 ppt | 7.8 | 8 |
| PFHxS | 3 ppt | 7 | 8 |
| PFOA | 4 ppt | 10.2 | 10.2 |
| PFOS | 4 ppt | 11.2 | 12.4 |
| PFPeA | 3 ppt | 12.2 | 12.5 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | < 5 |
| 4:2 FTS | 3 ppt | < 3 | < 3 |
| 6:2 FTS | 5 ppt | < 5 | < 5 |
| 8:2 FTS | 5 ppt | < 5 | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | < 2 |
| ADONA | 3 ppt | < 3 | < 3 |
| HFPO-DA | 5 ppt | < 5 | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 |
| NFDHA | 20 ppt | < 20 | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 |
| PFBA | 5 ppt | < 5 | < 5 |
| PFDA | 3 ppt | < 3 | < 3 |
| PFDoA | 3 ppt | < 3 | < 3 |
| PFEESA | 3 ppt | < 3 | < 3 |
| PFHpS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFPeS | 4 ppt | < 4 | < 4 |
| PFTA | 8 ppt | < 8 | < 8 |
| PFTrDA | 7 ppt | < 7 | < 7 |
| PFUnA | 2 ppt | < 2 | < 2 |
| lithium | 9 µg/L | 88.5 | 76 |
Townwell Reservoir facility 90001 · sample point POE001 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 |
|---|---|---|---|
| PFHxA | 3 ppt | 3.4 | < 3 |
| PFHxS | 3 ppt | 5.9 | 5 |
| PFOA | 4 ppt | 5 | 4.1 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | < 5 |
| 4:2 FTS | 3 ppt | < 3 | < 3 |
| 6:2 FTS | 5 ppt | < 5 | < 5 |
| 8:2 FTS | 5 ppt | < 5 | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | < 2 |
| ADONA | 3 ppt | < 3 | < 3 |
| HFPO-DA | 5 ppt | < 5 | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 |
| NFDHA | 20 ppt | < 20 | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 |
| PFBA | 5 ppt | < 5 | < 5 |
| PFBS | 3 ppt | < 3 | < 3 |
| PFDA | 3 ppt | < 3 | < 3 |
| PFDoA | 3 ppt | < 3 | < 3 |
| PFEESA | 3 ppt | < 3 | < 3 |
| PFHpA | 3 ppt | < 3 | < 3 |
| PFHpS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOS | 4 ppt | < 4 | < 4 |
| PFPeA | 3 ppt | < 3 | < 3 |
| PFPeS | 4 ppt | < 4 | < 4 |
| PFTA | 8 ppt | < 8 | < 8 |
| PFTrDA | 7 ppt | < 7 | < 7 |
| PFUnA | 2 ppt | < 2 | < 2 |
| lithium | 9 µg/L | 85.7 | 72.7 |
Well 10 Airline facility 90005 · sample point POE005 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 |
|---|---|---|---|
| PFBA | 5 ppt | 8.2 | 10 |
| PFHxA | 3 ppt | < 3 | 4 |
| PFHxS | 3 ppt | 5.6 | 8.2 |
| PFOS | 4 ppt | 8.5 | 12 |
| PFPeA | 3 ppt | 3.2 | 9.7 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | < 5 |
| 4:2 FTS | 3 ppt | < 3 | < 3 |
| 6:2 FTS | 5 ppt | < 5 | < 5 |
| 8:2 FTS | 5 ppt | < 5 | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | < 2 |
| ADONA | 3 ppt | < 3 | < 3 |
| HFPO-DA | 5 ppt | < 5 | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 |
| NFDHA | 20 ppt | < 20 | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 |
| PFBS | 3 ppt | < 3 | < 3 |
| PFDA | 3 ppt | < 3 | < 3 |
| PFDoA | 3 ppt | < 3 | < 3 |
| PFEESA | 3 ppt | < 3 | < 3 |
| PFHpA | 3 ppt | < 3 | < 3 |
| PFHpS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 4 ppt | < 4 | < 4 |
| PFPeS | 4 ppt | < 4 | < 4 |
| PFTA | 8 ppt | < 8 | < 8 |
| PFTrDA | 7 ppt | < 7 | < 7 |
| PFUnA | 2 ppt | < 2 | < 2 |
| lithium | 9 µg/L | 67.8 | 102 |
Well 2 Airline facility 90004 · sample point POE004 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 | 2024-04-16 SE2 |
|---|---|---|---|---|
| PFBA | 5 ppt | 20.3 | – | < 5 |
| PFBS | 3 ppt | 8.4 | – | < 3 |
| PFHpA | 3 ppt | 6.1 | – | < 3 |
| PFHxA | 3 ppt | 23.2 | – | < 3 |
| PFHxS | 3 ppt | 7.9 | – | < 3 |
| PFOA | 4 ppt | 5.9 | – | < 4 |
| PFOS | 4 ppt | 7.8 | – | < 4 |
| PFPeA | 3 ppt | 54.6 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | < 3 | – | < 3 |
| 6:2 FTS | 5 ppt | < 5 | – | < 5 |
| 8:2 FTS | 5 ppt | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | – | < 2 |
| ADONA | 3 ppt | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 | – |
| NFDHA | 20 ppt | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 | – |
| PFDA | 3 ppt | < 3 | – | < 3 |
| PFDoA | 3 ppt | < 3 | – | < 3 |
| PFEESA | 3 ppt | < 3 | – | < 3 |
| PFHpS | 3 ppt | < 3 | – | < 3 |
| PFMBA | 3 ppt | < 3 | – | < 3 |
| PFMPA | 4 ppt | < 4 | – | < 4 |
| PFNA | 4 ppt | < 4 | – | < 4 |
| PFPeS | 4 ppt | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | < 7 | – |
| PFUnA | 2 ppt | < 2 | – | < 2 |
| lithium | 9 µg/L | 74.6 | 77.6 | – |
Well 20-B facility 90002 · sample point POE002 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 | 2024-04-03 SE2 |
|---|---|---|---|---|
| PFBS | 3 ppt | < 3 | – | 4.8 |
| PFHpA | 3 ppt | < 3 | – | 3.4 |
| PFHxA | 3 ppt | 4.4 | – | 9.1 |
| PFHxS | 3 ppt | 4.6 | – | 8.7 |
| PFOA | 4 ppt | 4.1 | – | 6.7 |
| PFOS | 4 ppt | 4.5 | – | 7.5 |
| PFPeA | 3 ppt | 6.6 | – | 9.6 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | < 3 | – | < 3 |
| 6:2 FTS | 5 ppt | < 5 | – | < 5 |
| 8:2 FTS | 5 ppt | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | – | < 2 |
| ADONA | 3 ppt | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 | – |
| NFDHA | 20 ppt | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 | – |
| PFBA | 5 ppt | < 5 | – | < 5 |
| PFDA | 3 ppt | < 3 | – | < 3 |
| PFDoA | 3 ppt | < 3 | – | < 3 |
| PFEESA | 3 ppt | < 3 | – | < 3 |
| PFHpS | 3 ppt | < 3 | – | < 3 |
| PFMBA | 3 ppt | < 3 | – | < 3 |
| PFMPA | 4 ppt | < 4 | – | < 4 |
| PFNA | 4 ppt | < 4 | – | < 4 |
| PFPeS | 4 ppt | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | < 7 | – |
| PFUnA | 2 ppt | < 2 | – | < 2 |
| lithium | 9 µg/L | 111 | 77.3 | – |
Well 34-C facility 90006 · sample point POE006 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-20 SE2 |
|---|---|---|---|
| PFBS | 3 ppt | 3.8 | 5.3 |
| PFHxS | 3 ppt | 4.8 | 4.1 |
| PFOS | 4 ppt | 4.4 | 5 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | < 5 |
| 4:2 FTS | 3 ppt | < 3 | < 3 |
| 6:2 FTS | 5 ppt | < 5 | < 5 |
| 8:2 FTS | 5 ppt | < 5 | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | < 2 |
| ADONA | 3 ppt | < 3 | < 3 |
| HFPO-DA | 5 ppt | < 5 | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 |
| NFDHA | 20 ppt | < 20 | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 |
| PFBA | 5 ppt | < 5 | < 5 |
| PFDA | 3 ppt | < 3 | < 3 |
| PFDoA | 3 ppt | < 3 | < 3 |
| PFEESA | 3 ppt | < 3 | < 3 |
| PFHpA | 3 ppt | < 3 | < 3 |
| PFHpS | 3 ppt | < 3 | < 3 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 4 ppt | < 4 | < 4 |
| PFPeA | 3 ppt | < 3 | < 3 |
| PFPeS | 4 ppt | < 4 | < 4 |
| PFTA | 8 ppt | < 8 | < 8 |
| PFTrDA | 7 ppt | < 7 | < 7 |
| PFUnA | 2 ppt | < 2 | < 2 |
| lithium | 9 µg/L | 92.2 | 86.4 |
Well Marbella 1 facility 90007 · sample point POE007 · groundwater
| Compound | MRL | 2023-09-13 SE1 | 2024-03-21 SE2 | 2024-04-16 SE2 |
|---|---|---|---|---|
| PFBS | 3 ppt | 5 | – | < 3 |
| PFHpA | 3 ppt | 3.4 | – | < 3 |
| PFHxA | 3 ppt | 7.2 | – | 3 |
| PFHxS | 3 ppt | 18.9 | – | 8.3 |
| PFOA | 4 ppt | 5.6 | – | < 4 |
| PFOS | 4 ppt | 14.1 | – | < 4 |
| PFPeA | 3 ppt | 7.8 | – | < 3 |
| 11Cl-PF3OUdS | 5 ppt | < 5 | – | < 5 |
| 4:2 FTS | 3 ppt | < 3 | – | < 3 |
| 6:2 FTS | 5 ppt | < 5 | – | < 5 |
| 8:2 FTS | 5 ppt | < 5 | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | < 2 | – | < 2 |
| ADONA | 3 ppt | < 3 | – | < 3 |
| HFPO-DA | 5 ppt | < 5 | – | < 5 |
| NEtFOSAA | 5 ppt | < 5 | < 5 | – |
| NFDHA | 20 ppt | < 20 | – | < 20 |
| NMeFOSAA | 6 ppt | < 6 | < 6 | – |
| PFBA | 5 ppt | < 5 | – | < 5 |
| PFDA | 3 ppt | < 3 | – | < 3 |
| PFDoA | 3 ppt | < 3 | – | < 3 |
| PFEESA | 3 ppt | < 3 | – | < 3 |
| PFHpS | 3 ppt | < 3 | – | < 3 |
| PFMBA | 3 ppt | < 3 | – | < 3 |
| PFMPA | 4 ppt | < 4 | – | < 4 |
| PFNA | 4 ppt | < 4 | – | < 4 |
| PFPeS | 4 ppt | < 4 | – | < 4 |
| PFTA | 8 ppt | < 8 | < 8 | – |
| PFTrDA | 7 ppt | < 7 | < 7 | – |
| PFUnA | 2 ppt | < 2 | – | < 2 |
| lithium | 9 µg/L | 99.9 | 166 | – |
Statistics by compound
| Compound | Results | Detected | Highest (date) | Mean bounds | KM median | P75 | P90 | P95 |
|---|---|---|---|---|---|---|---|---|
| lithium | 14 | 100% | 166 2024-03-21 | 91.26–91.26 | 85.7 | 99.9 | 111 | 166 |
| PFHxS | 14 | 93% | 18.9 2023-09-13 | 6.93–7.14 | 5.9 | 8.2 | 8.7 | 18.9 |
| PFOS | 14 | 71% | 14.1 2023-09-13 | 6.24–7.39 | 5 | 11.2 | 12.4 | 14.1 |
| PFHxA | 14 | 64% | 23.2 2023-09-13 | 5.01–6.08 | 3.4 | 7.8 | 9.1 | 23.2 |
| PFOA | 14 | 57% | 10.2 2023-09-13 | 3.7–5.41 | 4.1 | 5.9 | 10.2 | 10.2 |
| PFPeA | 14 | 57% | 54.6 2023-09-13 | 8.3–9.59 | 3.2 | 9.7 | 12.5 | 54.6 |
| PFBS | 14 | 50% | 8.4 2023-09-13 | 2.74–4.24 | <MRL | 5.2 | 5.8 | 8.4 |
| PFHpA | 14 | 36% | 6.1 2023-09-13 | 1.42–3.35 | <MRL | 3.4 | 3.7 | 6.1 |
| PFBA | 14 | 21% | 20.3 2023-09-13 | 2.75–6.68 | <MRL | <MRL | 10 | 20.3 |
Never detected (21): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFDA, PFDoA, PFEESA, PFHpS, PFMBA, PFMPA, PFNA, PFPeS, PFTA, PFTrDA, PFUnA.
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 2023-01-03 to 2026-06-02; 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 e94d59d510ac · 2026-10-18T04:09Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.