Community Water System · PWS NN0400342
Dilkon-Indian Wells-Greasewood-White Cone NTUA
Operator location Fort Defiance, Navajo Nation - 48% of 223 violations are health-based (upper-third health share (> 23%)); groundwater source; 4,986 served per SDWIS.
- 4,986
- People served (this PWS) Larger third of systems
- 223
- EPA violations (this PWS) Upper third of systems
- 107
- Health-based (this PWS) Upper third by health-based share
- No PFAS
- UCMR5 (this PWS) Tested, none detected
Dilkon-Indian Wells-Greasewood-White Cone NTUA standing, high SDWIS violation third
48% of 223 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 48% is upper-third health share (> 23%). UCMR5: UCMR5 tested, none detected. Population rank #7,768 of 29,740 among systems serving 500+.
The verdict
Dilkon-Indian Wells-Greasewood-White Cone NTUA sits in the upper third of the sitemap cohort by violation count (223), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (4,986; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 48% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #7,768 of 29,740
- Population · /systems
- #6 of 82
- Population · NN
- 223
- Total EPA violations on record
- 48%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 1,458
- School/Daycare
- No
- MCL Violations
- 105
- Monitoring Violations
- 59
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MCL | 71 | 2021 |
| Coliform (TCR) | MCL | 34 | 2015 |
| Public Notice | Other | 14 | 2022 |
| Total Haloacetic Acids (HAA5) | MR | 10 | 2015 |
| TTHM | MR | 10 | 2015 |
| Coliform (TCR) | MR | 9 | 2012 |
| Revised Total Coliform Rule | MON | 4 | 2022 |
| Revised Total Coliform Rule | TT | 2 | 2016 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2005 |
| cis-1,2-Dichloroethylene | MR | 1 | 2005 |
| DICHLOROMETHANE | MR | 1 | 2005 |
| o-Dichlorobenzene | MR | 1 | 2005 |
| trans-1,2-Dichloroethylene | MR | 1 | 2005 |
| 1,2-Dichloroethane | MR | 1 | 2005 |
| 1,2-Dichloropropane | MR | 1 | 2005 |
| Trichloroethylene | MR | 1 | 2005 |
| CHLOROBENZENE | MR | 1 | 2005 |
| Ethylbenzene | MR | 1 | 2005 |
| Styrene | MR | 1 | 2005 |
| Combined Radium (-226 and -228) | MR | 1 | 2005 |
| Lead and Copper Rule | MR | 1 | 2004 |
| Revised Total Coliform Rule | Other | 1 | 2016 |
| Combined Uranium | MR | 1 | 2005 |
| Xylenes, Total | MR | 1 | 2005 |
| Tetrachloroethylene | MR | 1 | 2005 |
| 1,1-Dichloroethylene | MR | 1 | 2005 |
| Toluene | MR | 1 | 2005 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 2005 |
| p-Dichlorobenzene | MR | 1 | 2005 |
| E. COLI | MR | 1 | 2013 |
Violation Count vs. the National Corpus
Dilkon-Indian Wells-Greasewood-White Cone NTUA has 223 recorded EPA violations, 87% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 13% carry more. 48% of this system's own violations are health-based (107 of 223), and it ranks #7,768 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
223 Higher than most more violations than 87% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
How many violations vs. how serious, among peer systems
Dilkon-Indian Wells-Greasewood-White Cone NTUA plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 87 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFDoA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 6/16/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/16/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| HFPO-DA | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFDA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 6/16/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| ADONA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 6/16/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFBA | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 6/16/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| 6:2 FTS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 6/16/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFPeS | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 6/16/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFMBA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFEESA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/16/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/16/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 6/16/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTA | 6/16/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 6/16/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFDoA | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 6/16/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFBS | 6/16/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
Health-based violations on Dilkon-Indian Wells-Greasewood-White Cone NTUA
107 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NN0400342.
Sources: EPA SDWIS
Nationwide peers
223 violations · 4,986 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Dilkon-Indian Wells-Greasewood-White Cone NTUA
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Navajo Nation compares on the same EPA violation measures. Navajo Nation systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.