Round Rock NTUA
PWS ID: NN0403023 · Ft Defiance, Navajo Nation 86504
Population Served
876
Total Violations
61
Health-Based Violations
26
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 256
- School/Daycare
- No
- MCL Violations
- 26
- Monitoring Violations
- 23
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Combined Radium (-226 and -228) | MCL | 24 | 2013 |
| Coliform (TCR) | MR | 9 | 2012 |
| Nitrate | MR | 3 | 2010 |
| TTHM | MR | 3 | 2020 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2020 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Coliform (TCR) | MCL | 2 | 2007 |
| Nitrite | MR | 1 | 2010 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 2004 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.