Gwa Northern Water System
PWSID GU0000006 · Mangilao, Guam · serves 139,207 people · groundwater source
C
Fair
PFAS test results (EPA UCMR 5)
| Contaminant | Result | Federal limit (MCL) | Sampled |
|---|---|---|---|
| 6:2 FTS | 148.2 ppt | — | 9/28/2023 |
| PFOS | 135 ppt | 4 ppt | 9/20/2023 |
| PFHxS | 80 ppt | 10 ppt | 9/20/2023 |
| PFOS | 76.5 ppt | 4 ppt | 9/21/2023 |
| 6:2 FTS | 68.3 ppt | — | 3/26/2024 |
| PFOS | 61.3 ppt | 4 ppt | 3/23/2024 |
| PFOS | 60.6 ppt | 4 ppt | 9/21/2023 |
| 6:2 FTS | 56.3 ppt | — | 9/20/2023 |
| PFPeA | 47.5 ppt | — | 9/21/2023 |
| PFHxA | 37.1 ppt | — | 9/20/2023 |
| PFHxS | 35.2 ppt | 10 ppt | 3/23/2024 |
| PFBS | 34.9 ppt | — | 9/21/2023 |
| PFHxA | 34.4 ppt | — | 9/21/2023 |
| PFPeA | 33.8 ppt | — | 3/26/2024 |
| PFHxS | 32 ppt | 10 ppt | 9/21/2023 |
| PFBS | 29.8 ppt | — | 3/26/2024 |
| PFHxS | 29.4 ppt | 10 ppt | 9/21/2023 |
| PFOS | 28.3 ppt | 4 ppt | 9/24/2023 |
| PFHxA | 27.1 ppt | — | 3/26/2024 |
| PFHxS | 25.7 ppt | 10 ppt | 12/12/2023 |
| PFHxS | 24.8 ppt | 10 ppt | 3/21/2024 |
| PFHxS | 22.3 ppt | 10 ppt | 9/24/2023 |
| PFPeA | 20.7 ppt | — | 11/2/2023 |
| PFBS | 20.5 ppt | — | 3/28/2024 |
| PFPeA | 19.8 ppt | — | 3/26/2024 |
| PFHpA | 18.5 ppt | — | 9/21/2023 |
| PFPeA | 18.4 ppt | — | 9/17/2023 |
| PFOA | 18.3 ppt | 4 ppt | 9/20/2023 |
| PFBA | 18.1 ppt | — | 9/21/2023 |
| PFPeA | 17.8 ppt | — | 9/28/2023 |
| PFOS | 16.8 ppt | 4 ppt | 9/21/2023 |
| PFOA | 16.2 ppt | 4 ppt | 9/21/2023 |
| PFPeA | 16.2 ppt | — | 9/20/2023 |
| PFOS | 16.2 ppt | 4 ppt | 3/23/2024 |
| PFOS | 15.9 ppt | 4 ppt | 3/23/2024 |
| PFOS | 15.8 ppt | 4 ppt | 9/21/2023 |
| PFPeA | 15.6 ppt | — | 3/28/2024 |
| PFOS | 15.4 ppt | 4 ppt | 9/21/2023 |
| PFOS | 15.1 ppt | 4 ppt | 3/23/2024 |
| PFHxA | 14.5 ppt | — | 3/26/2024 |
| PFPeA | 14.5 ppt | — | 3/23/2024 |
| PFBS | 14.5 ppt | — | 3/23/2024 |
| PFOS | 14.2 ppt | 4 ppt | 3/23/2024 |
| PFOS | 14 ppt | 4 ppt | 9/21/2023 |
| PFHpA | 14 ppt | — | 9/20/2023 |
| PFHxA | 14 ppt | — | 11/2/2023 |
| PFHxS | 13.8 ppt | 10 ppt | 10/26/2023 |
| PFHxS | 13.8 ppt | 10 ppt | 3/27/2024 |
| PFOS | 13.4 ppt | 4 ppt | 3/23/2024 |
| PFOS | 13.1 ppt | 4 ppt | 9/21/2023 |
ppt = parts per trillion (ng/L). Rows highlighted red meet or exceed the 2024 federal limit.
Violation history
No violations on record in the period covered. 🎉