Fort Defiance-Window Rock-St Michaels NTUA
PWS ID: NN0403000 · Ft Defiance, Navajo Nation 86504
PFAS Detected
1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
Population Served
12,869
Total Violations
248
Health-Based Violations
43
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 3,763
- School/Daycare
- No
- MCL Violations
- 41
- Monitoring Violations
- 177
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MCL | 19 | 2017 |
| Total Haloacetic Acids (HAA5) | MR | 13 | 2018 |
| TTHM | MR | 13 | 2018 |
| Coliform (TCR) | MCL | 11 | 2014 |
| Combined Uranium | MCL | 7 | 2013 |
| Coliform (TCR) | MR | 7 | 2016 |
| Public Notice | Other | 6 | 2025 |
| cis-1,2-Dichloroethylene | MR | 5 | 2011 |
| Xylenes, Total | MR | 5 | 2011 |
| DICHLOROMETHANE | MR | 5 | 2011 |
| o-Dichlorobenzene | MR | 5 | 2011 |
| Vinyl chloride | MR | 5 | 2011 |
| trans-1,2-Dichloroethylene | MR | 5 | 2011 |
| 1,2-Dichloropropane | MR | 5 | 2011 |
| Tetrachloroethylene | MR | 5 | 2011 |
| Toluene | MR | 5 | 2011 |
| Ethylbenzene | MR | 5 | 2011 |
| Styrene | MR | 5 | 2011 |
| CHLOROBENZENE | MR | 5 | 2011 |
| p-Dichlorobenzene | MR | 5 | 2011 |
| ETHYLENE DIBROMIDE | MR | 4 | 2011 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 4 | 2011 |
| 1,2,4-Trichlorobenzene | MR | 3 | 2011 |
| 1,1-Dichloroethylene | MR | 3 | 2011 |
| 1,2-Dichloroethane | MR | 3 | 2011 |
| 1,1,1-Trichloroethane | MR | 3 | 2011 |
| Carbon tetrachloride | MR | 3 | 2011 |
| Trichloroethylene | MR | 3 | 2011 |
| 1,1,2-Trichloroethane | MR | 3 | 2011 |
| Benzene | MR | 3 | 2011 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 12 of 420 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| 4:2 FTS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFNA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFDA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFDoA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFUnA | 8/18/2025 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| 11Cl-PF3OUdS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 9Cl-PF3ONS | 8/18/2025 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| ADONA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 6:2 FTS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NFDHA | 8/18/2025 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| NMeFOSAA | 8/18/2025 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| NEtFOSAA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFTrDA | 8/18/2025 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| PFTA | 8/18/2025 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| lithium | 8/18/2025 | 124.0000 µg/L | 9 µg/L | Detected |
| PFBA | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFPeS | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFHpA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFEESA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMPA | 8/18/2025 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| 8:2 FTS | 8/18/2025 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFHpS | 8/18/2025 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFDoA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 11Cl-PF3OUdS | 7/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFUnA | 7/23/2024 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| PFTA | 7/23/2024 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFTrDA | 7/23/2024 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| NEtFOSAA | 7/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NMeFOSAA | 7/23/2024 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| PFHxA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 7/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFDA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFOA | 7/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 7/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFNA | 7/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFHxS | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| lithium | 7/23/2024 | 31.5000 µg/L | 9 µg/L | Detected |
| PFEESA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBS | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpS | 7/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
PFAS data from EPA UCMR5 monitoring program (2023-2025).
This data is provided for informational purposes only.