- PWSID
- MP0000001
- System type
- community water system (CWS)
- Population served
- 48,524
- City
- Saipan
- Counties
- Saipan Municipality
- Primary source water
- groundwater
- UCMR 5 sampling
- 2023-10-18 to 2024-09-09 · 15 entry point(s) · water types: GW
- Service-area boundary
- authoritative
PFOS ≥ 3 × its limit highest single result
PFOS ≥ 3 × its limit worst entry-point average
Open on the Northern Mariana Islands map · All Northern Mariana Islands 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) | <MRL | 0 | 4 |
| PFOS (ppt) | 32.1 | 32.1 | 4 |
| Hazard Index | 1.967 | 1.967 | 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).
Compared with Northern Mariana Islands standards
| Highest single result | Worst entry-point average* | Northern Mariana Islands | |
|---|---|---|---|
| PFOS+PFOA+PFNA (sum) (ppt) | 32.1 | 32.1 | 70 |
Sum standards add the listed compounds within each sample (non-detects = 0). State compliance is normally judged on averages over time; these are screening comparisons.
Sampling history
Sampled 2023-10-18 to 2024-09-09 · 15 entry point(s) · water types: GW · 36 sampling visits. PFAS in ppt (ng/L).
| Date | Entry point | Event | PFOA | PFOS | HI | Other detections |
|---|---|---|---|---|---|---|
| 2023-10-18 | As Terlaje Tank (GW) | SE1 | n/a | n/a | n/a | lithium 11.9 µg/L |
| 2023-10-18 | Dandan Reservoir (GW) | SE1 | n/a | n/a | n/a | lithium 9.33 µg/L |
| 2023-10-18 | GR 4/5 EP @ GR-4 (GW) | SE1 | <4 | <4 | 0 | lithium 16.9 µg/L |
| 2023-10-18 | IF 28 EP (GW) | SE1 | <4 | <4 | 0 | PFHxA 3.3, PFPeA 10.5 |
| 2023-10-18 | Isley Reservoir (GW) | SE1 | n/a | n/a | n/a | none |
| 2023-10-18 | San Vicente Reservoir (GW) | SE1 | n/a | n/a | n/a | lithium 9.41 µg/L |
| 2023-10-19 | Gualo Rai Reservoir (GW) | SE1 | <4 | <4 | 0 | lithium 12.7 µg/L |
| 2023-10-25 | Agag Reservoir (GW) | SE1 | <4 | <4 | 0 | none |
| 2023-10-25 | Calhoun Reservoir (GW) | SE1 | <4 | <4 | 0 | none |
| 2023-10-25 | Capitol Hill Reservoir (GW) | SE1 | <4 | <4 | 0 | none |
| 2023-10-25 | Kagman Tank Outlet (GW) | SE1 | <4 | <4 | 0 | lithium 11.2 µg/L |
| 2023-10-25 | Marpi Reservoir (GW) | SE1 | <4 | <4 | 0 | lithium 58.4 µg/L |
| 2023-10-25 | Maui 4 Sumptank (GW) | SE1 | <4 | <4 | 0 | none |
| 2023-10-25 | Puerto Rico Reservoir (GW) | SE1 | n/a | n/a | n/a | none |
| 2023-10-25 | Rapagao Reservoir (GW) | SE1 | n/a | n/a | n/a | none |
| 2024-01-16 | GR 4/5 EP @ GR-4 (GW) | SE1 | n/a | n/a | n/a | none |
| 2024-01-16 | IF 28 EP (GW) | SE1 | n/a | n/a | n/a | none |
| 2024-01-16 | Puerto Rico Reservoir (GW) | SE1 | <4 | 4.2 | 0 | none |
| 2024-03-08 | Agag Reservoir (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-03-08 | Capitol Hill Reservoir (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-03-08 | Kagman Tank Outlet (GW) | SE2 | <4 | <4 | 0 | lithium 16.9 µg/L |
| 2024-03-08 | Marpi Reservoir (GW) | SE2 | <4 | <4 | 0 | lithium 46.3 µg/L |
| 2024-03-08 | Maui 4 Sumptank (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-03-08 | Puerto Rico Reservoir (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-03-08 | Rapagao Reservoir (GW) | SE2 | <4 | 5.4 | 0 | none |
| 2024-03-15 | As Terlaje Tank (GW) | SE2 | <4 | 24.1 | 1.967 | 6:2 FTS 12.5, PFBA 32.3, PFHpA 22.9, PFHxA 121.6, PFPeA 133.8, PFPeS 5.4, lithium 11.1 µg/L |
| 2024-03-15 | Calhoun Reservoir (GW) | SE2 | <4 | <4 | 0 | none |
| 2024-03-15 | Dandan Reservoir (GW) | SE2 | <4 | 32.1 | 1.882 | 6:2 FTS 9.7, PFHpA 5.1, PFHxA 8.2, PFPeA 10.1, lithium 10.3 µg/L |
| 2024-03-15 | GR 4/5 EP @ GR-4 (GW) | SE2 | <4 | <4 | 0 | lithium 25.6 µg/L |
| 2024-03-15 | Gualo Rai Reservoir (GW) | SE2 | <4 | <4 | 0 | lithium 9.43 µg/L |
| 2024-03-15 | IF 28 EP (GW) | SE2 | <4 | 5.9 | 0.512 | PFHpA 3.9, PFHxA 7.3, PFPeA 7 |
| 2024-03-15 | Isley Reservoir (GW) | SE2 | <4 | 15.4 | 1.332 | PFHpA 5, PFHxA 12.2, PFPeA 12.6 |
| 2024-03-15 | San Vicente Reservoir (GW) | SE2 | <4 | <4 | 0 | lithium 16.9 µg/L |
| 2024-09-09 | Maui 4 Sumptank (GW) | SE2 | n/a | n/a | n/a | none |
| 2024-09-09 | Rapagao Reservoir (GW) | SE1 | <4 | 4 | 0 | PFPeA 3.2 |
| 2024-09-09 | San Vicente Reservoir (GW) | SE1 | <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
813 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.
Agag Reservoir facility 90010 · sample point EP112 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | < 9 | < 9 |
As Terlaje Tank facility 90043 · sample point EP116 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-03-15 SE2 |
|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 12.5 |
| PFBA | 5 ppt | – | 32.3 |
| PFBS | 3 ppt | – | 14.6 |
| PFHpA | 3 ppt | – | 22.9 |
| PFHxA | 3 ppt | – | 121.6 |
| PFHxS | 3 ppt | – | 19.6 |
| PFOS | 4 ppt | – | 24.1 |
| PFPeA | 3 ppt | – | 133.8 |
| PFPeS | 4 ppt | – | 5.4 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 |
| ADONA | 3 ppt | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 |
| NEtFOSAA | 5 ppt | – | < 5 |
| NFDHA | 20 ppt | – | < 20 |
| NMeFOSAA | 6 ppt | – | < 6 |
| PFDA | 3 ppt | – | < 3 |
| PFDoA | 3 ppt | – | < 3 |
| PFEESA | 3 ppt | – | < 3 |
| PFHpS | 3 ppt | – | < 3 |
| PFMBA | 3 ppt | – | < 3 |
| PFMPA | 4 ppt | – | < 4 |
| PFNA | 4 ppt | – | < 4 |
| PFOA | 4 ppt | – | < 4 |
| PFTA | 8 ppt | – | < 8 |
| PFTrDA | 7 ppt | – | < 7 |
| PFUnA | 2 ppt | – | < 2 |
| lithium | 9 µg/L | 11.9 | 11.1 |
Calhoun Reservoir facility 90006 · sample point EP110 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-15 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | < 9 | < 9 |
Capitol Hill Reservoir facility 90005 · sample point EP109 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | < 9 | < 9 |
Dandan Reservoir facility 90038 · sample point EP119 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-03-15 SE2 |
|---|---|---|---|
| 6:2 FTS | 5 ppt | – | 9.7 |
| PFBS | 3 ppt | – | 3.3 |
| PFHpA | 3 ppt | – | 5.1 |
| PFHxA | 3 ppt | – | 8.2 |
| PFHxS | 3 ppt | – | 18.8 |
| PFOS | 4 ppt | – | 32.1 |
| PFPeA | 3 ppt | – | 10.1 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 |
| 8:2 FTS | 5 ppt | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 |
| ADONA | 3 ppt | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 |
| NEtFOSAA | 5 ppt | – | < 5 |
| NFDHA | 20 ppt | – | < 20 |
| NMeFOSAA | 6 ppt | – | < 6 |
| PFBA | 5 ppt | – | < 5 |
| PFDA | 3 ppt | – | < 3 |
| PFDoA | 3 ppt | – | < 3 |
| PFEESA | 3 ppt | – | < 3 |
| PFHpS | 3 ppt | – | < 3 |
| PFMBA | 3 ppt | – | < 3 |
| PFMPA | 4 ppt | – | < 4 |
| PFNA | 4 ppt | – | < 4 |
| PFOA | 4 ppt | – | < 4 |
| PFPeS | 4 ppt | – | < 4 |
| PFTA | 8 ppt | – | < 8 |
| PFTrDA | 7 ppt | – | < 7 |
| PFUnA | 2 ppt | – | < 2 |
| lithium | 9 µg/L | 9.33 | 10.3 |
GR 4/5 EP @ GR-4 facility 90008 · sample point EP321 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-01-16 SE1 | 2024-03-15 SE2 |
|---|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | – | < 3 |
| PFHxS | 3 ppt | < 3 | – | < 3 |
| PFMBA | 3 ppt | < 3 | – | < 3 |
| PFMPA | 4 ppt | < 4 | – | < 4 |
| PFNA | 4 ppt | < 4 | – | < 4 |
| PFOA | 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 | 16.9 | – | 25.6 |
Gualo Rai Reservoir facility 90007 · sample point EP111 · groundwater
| Compound | MRL | 2023-10-19 SE1 | 2024-03-15 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | 12.7 | 9.43 |
IF 28 EP facility 90032 · sample point EP028 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-01-16 SE1 | 2024-03-15 SE2 |
|---|---|---|---|---|
| PFBS | 3 ppt | < 3 | – | 3.6 |
| PFHpA | 3 ppt | < 3 | – | 3.9 |
| PFHxA | 3 ppt | 3.3 | – | 7.3 |
| PFHxS | 3 ppt | < 3 | – | 5.1 |
| PFOS | 4 ppt | < 4 | – | 5.9 |
| PFPeA | 3 ppt | 10.5 | – | 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 |
| 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 |
| 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 | < 9 | – | < 9 |
Isley Reservoir facility 90014 · sample point EP115 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-03-15 SE2 |
|---|---|---|---|
| PFBS | 3 ppt | – | 3.6 |
| PFHpA | 3 ppt | – | 5 |
| PFHxA | 3 ppt | – | 12.2 |
| PFHxS | 3 ppt | – | 13.3 |
| PFOS | 4 ppt | – | 15.4 |
| PFPeA | 3 ppt | – | 12.6 |
| 11Cl-PF3OUdS | 5 ppt | – | < 5 |
| 4:2 FTS | 3 ppt | – | < 3 |
| 6:2 FTS | 5 ppt | – | < 5 |
| 8:2 FTS | 5 ppt | – | < 5 |
| 9Cl-PF3ONS | 2 ppt | – | < 2 |
| ADONA | 3 ppt | – | < 3 |
| HFPO-DA | 5 ppt | – | < 5 |
| NEtFOSAA | 5 ppt | – | < 5 |
| NFDHA | 20 ppt | – | < 20 |
| NMeFOSAA | 6 ppt | – | < 6 |
| PFBA | 5 ppt | – | < 5 |
| PFDA | 3 ppt | – | < 3 |
| PFDoA | 3 ppt | – | < 3 |
| PFEESA | 3 ppt | – | < 3 |
| PFHpS | 3 ppt | – | < 3 |
| PFMBA | 3 ppt | – | < 3 |
| PFMPA | 4 ppt | – | < 4 |
| PFNA | 4 ppt | – | < 4 |
| PFOA | 4 ppt | – | < 4 |
| PFPeS | 4 ppt | – | < 4 |
| PFTA | 8 ppt | – | < 8 |
| PFTrDA | 7 ppt | – | < 7 |
| PFUnA | 2 ppt | – | < 2 |
| lithium | 9 µg/L | < 9 | < 9 |
Kagman Tank Outlet facility 90031 · sample point EP103 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | 11.2 | 16.9 |
Marpi Reservoir facility 90001 · sample point EP101 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 |
|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | < 3 | < 3 |
| PFHxS | 3 ppt | < 3 | < 3 |
| PFMBA | 3 ppt | < 3 | < 3 |
| PFMPA | 4 ppt | < 4 | < 4 |
| PFNA | 4 ppt | < 4 | < 4 |
| PFOA | 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 | 58.4 | 46.3 |
Maui 4 Sumptank facility 90003 · sample point EP107 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 | 2024-09-09 SE2 |
|---|---|---|---|---|
| 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 | – |
| PFHxA | 3 ppt | < 3 | < 3 | – |
| PFHxS | 3 ppt | < 3 | < 3 | – |
| PFMBA | 3 ppt | < 3 | < 3 | – |
| PFMPA | 4 ppt | < 4 | < 4 | – |
| PFNA | 4 ppt | < 4 | < 4 | – |
| PFOA | 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 | < 9 | < 9 | – |
Puerto Rico Reservoir facility 90029 · sample point EP106 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-01-16 SE1 | 2024-03-08 SE2 |
|---|---|---|---|---|
| PFOS | 4 ppt | – | 4.2 | < 4 |
| 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 |
| PFHxA | 3 ppt | – | < 3 | < 3 |
| PFHxS | 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 | < 9 | – | < 9 |
Rapagao Reservoir facility 90040 · sample point EP238 · groundwater
| Compound | MRL | 2023-10-25 SE1 | 2024-03-08 SE2 | 2024-09-09 SE1 |
|---|---|---|---|---|
| PFOS | 4 ppt | – | 5.4 | 4 |
| PFPeA | 3 ppt | – | < 3 | 3.2 |
| 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 |
| PFHxA | 3 ppt | – | < 3 | < 3 |
| PFHxS | 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 | < 9 | < 9 | – |
San Vicente Reservoir facility 90012 · sample point EP114 · groundwater
| Compound | MRL | 2023-10-18 SE1 | 2024-03-15 SE2 | 2024-09-09 SE1 |
|---|---|---|---|---|
| 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 |
| PFHxA | 3 ppt | – | < 3 | < 3 |
| PFHxS | 3 ppt | – | < 3 | < 3 |
| PFMBA | 3 ppt | – | < 3 | < 3 |
| PFMPA | 4 ppt | – | < 4 | < 4 |
| PFNA | 4 ppt | – | < 4 | < 4 |
| PFOA | 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 | 9.41 | 16.9 | – |
Statistics by compound
| Compound | Results | Detected | Highest (date) | Mean bounds | KM median | P75 | P90 | P95 |
|---|---|---|---|---|---|---|---|---|
| lithium | 30 | 47% | 58.4 2023-10-25 | 8.88–13.68 | <MRL | 11.9 | 16.9 | 46.3 |
| PFOS | 27 | 26% | 32.1 2024-03-15 | 3.37–6.34 | <MRL | 4 | 15.4 | 24.1 |
| PFPeA | 27 | 22% | 133.8 2024-03-15 | 6.56–8.9 | <MRL | <MRL | 10.5 | 12.6 |
| PFHxA | 27 | 18% | 121.6 2024-03-15 | 5.65–8.1 | <MRL | <MRL | 8.2 | 12.2 |
| PFBS | 27 | 15% | 14.6 2024-03-15 | 0.93–3.49 | <MRL | <MRL | 3.6 | 3.6 |
| PFHpA | 27 | 15% | 22.9 2024-03-15 | 1.37–3.92 | <MRL | <MRL | 5 | 5.1 |
| PFHxS | 27 | 15% | 19.6 2024-03-15 | 2.1–4.66 | <MRL | <MRL | 13.3 | 18.8 |
| 6:2 FTS | 27 | 7% | 12.5 2024-03-15 | 0.82–5.45 | <MRL | <MRL | <MRL | 9.7 |
| PFBA | 27 | 4% | 32.3 2024-03-15 | 1.2–6.01 | <MRL | <MRL | <MRL | <MRL |
| PFPeS | 27 | 4% | 5.4 2024-03-15 | 0.2–4.05 | <MRL | <MRL | <MRL | <MRL |
Never detected (20): 11Cl-PF3OUdS, 4:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFDA, PFDoA, PFEESA, PFHpS, PFMBA, PFMPA, PFNA, PFOA, 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 2023-10-18 to 2025-08-04; 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 da0d8db3c9a3 · 2026-10-18T04:03Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.