What was found in ZIP 86504
The level at this ZIP's main supplier, the highest level anywhere in it, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 5800 µg/L 58% of the EPA limit 10000 µg/L Highest in the ZIP: Mariano Lake-Pinedale-Church Rock NTUA · 4,562 people · 2019 | 7/11 | SYR4 |
| Fluoride | 3395 µg/L 85% of the EPA limit 4000 µg/L Highest in the ZIP: Mariano Lake-Pinedale-Church Rock NTUA · 4,562 people · 2019 | 10/11 | SYR4 |
| Barium | 1926.5 µg/L 96% of the EPA limit 2000 µg/L Highest in the ZIP: Chinle-Many Farms-Del Muerto NTUA · 8,458 people · 2019 | 9/11 | SYR4 |
| Nitrite | 499 µg/L 50% of the EPA limit 1000 µg/L Highest in the ZIP: Dilkon-Indian Wells-Greasewood-White Cone NTUA · 4,986 people · 2019 | 9/11 | SYR4 |
| Lithium | 50.4 µg/L No EPA limit set Main supplier: Farmington Rural-Shiprock-Beclabito NTUA · 15,233 people · 2024
Highest in the ZIP: 230 µg/L — Ganado-Burnside-Cornfield-Steamboat NTUA · 3,947 people · 2024 | 11/11 | UCMR-5 |
| TTHM | 81.465 µg/L 102% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: Farmington Rural-Shiprock-Beclabito NTUA · 15,233 people · 2019
Highest in the ZIP: 180.9 µg/L — Dilkon-Indian Wells-Greasewood-White Cone NTUA · 4,986 people · 2019 | 11/11 | SYR4 |
| Total Haloacetic Acids (HAA5) | 36.755 µg/L 61% of the EPA limit 60 µg/L Main supplier: Farmington Rural-Shiprock-Beclabito NTUA · 15,233 people · 2019
Highest in the ZIP: 59.58 µg/L — Dilkon-Indian Wells-Greasewood-White Cone NTUA · 4,986 people · 2019 | 5/11 | SYR4 |
| Combined Uranium | 37.53 µg/L 125% of the EPA limit, at the 95th percentile of samples — 30 µg/L Highest in the ZIP: Fort Defiance-Window Rock-St Michaels NTUA · 12,869 people · 2019 | 10/11 | SYR4 |
| Arsenic | 22.04 µg/L 220% of the EPA limit, at the 95th percentile of samples — 10 µg/L Highest in the ZIP: Kayenta NTUA · 3,844 people · 2019 | 9/11 | SYR4 |
| Chromium | 19 µg/L 19% of the EPA limit 100 µg/L Highest in the ZIP: Crownpoint-Littlewater-Three Mile Point NTUA · 3,950 people · 2017 | 5/11 | SYR4 |
| Selenium | 18.9 µg/L 38% of the EPA limit 50 µg/L Highest in the ZIP: Crownpoint-Littlewater-Three Mile Point NTUA · 3,950 people · 2017 | 5/11 | SYR4 |
| Beryllium, Total | 6 µg/L 150% of the EPA limit, at the 95th percentile of samples — 4 µg/L Highest in the ZIP: Chinle-Many Farms-Del Muerto NTUA · 8,458 people · 2019 | 3/11 | SYR4 |
| Cadmium | 6 µg/L 120% of the EPA limit, at the 95th percentile of samples — 5 µg/L Highest in the ZIP: Chinle-Many Farms-Del Muerto NTUA · 8,458 people · 2019 | 1/11 | SYR4 |
| Gross Alpha, Excl. Radon And U | 4.8 pCi/L 32% of the EPA limit 15 pCi/L Highest in the ZIP: Mariano Lake-Pinedale-Church Rock NTUA · 4,562 people · 2019 | 9/11 | SYR4 |
| Combined Radium (-226 And -228) | 1.875 pCi/L 38% of the EPA limit 5 pCi/L Highest in the ZIP: Pinon-District 4 NTUA · 5,195 people · 2018 | 7/11 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 1.2 µg/L 20% of the EPA limit 6 µg/L Highest in the ZIP: Kayenta NTUA · 3,844 people · 2019 | 2/11 | SYR4 |
| Mercury | 1.04 µg/L 52% of the EPA limit 2 µg/L Highest in the ZIP: Ganado-Burnside-Cornfield-Steamboat NTUA · 3,947 people · 2019 | 8/11 | SYR4 |
| Thallium, Total | 0.9000 µg/L 45% of the EPA limit 2 µg/L Highest in the ZIP: Kayenta NTUA · 3,844 people · 2019 | 1/11 | SYR4 |
| Toluene | 0.9000 µg/L 0.1% of the EPA limit 1000 µg/L Highest in the ZIP: Mariano Lake-Pinedale-Church Rock NTUA · 4,562 people · 2019 | 1/11 | SYR4 |
| PFHXS | 0.0061 µg/L No EPA limit set Highest in the ZIP: Ganado-Burnside-Cornfield-Steamboat NTUA · 3,947 people · 2024 | 1/11 | UCMR-5 |
| 6:2 Fts | 0.0051 µg/L No EPA limit set Highest in the ZIP: Kayenta NTUA · 3,844 people · 2023 | 1/11 | UCMR-5 |
| Pfhxa | 0.0040 µg/L No EPA limit set Highest in the ZIP: Ganado-Burnside-Cornfield-Steamboat NTUA · 3,947 people · 2024 | 1/11 | UCMR-5 |
| Pfpea | 0.0036 µg/L No EPA limit set Highest in the ZIP: Ganado-Burnside-Cornfield-Steamboat NTUA · 3,947 people · 2024 | 1/11 | UCMR-5 |
| Lead | 0.0025 mg/L 17% of the EPA limit 0.0150 mg/L Main supplier: Farmington Rural-Shiprock-Beclabito NTUA · 15,233 people · 2025
Highest in the ZIP: 0.0029 mg/L — Mariano Lake-Pinedale-Church Rock NTUA · 4,562 people · 2025 | 11/11 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
Water suppliers serving ZIP 86504
| Supplier | State | Population served |
|---|---|---|
| Farmington Rural-Shiprock-Beclabito NTUA | AZ | 15,233 |
| Fort Defiance-Window Rock-St Michaels NTUA | AZ | 12,869 |
| Chinle-Many Farms-Del Muerto NTUA | AZ | 8,458 |
| Tuba City NTUA | AZ | 6,276 |
| Pinon-District 4 NTUA | AZ | 5,195 |
| Dilkon-Indian Wells-Greasewood-White Cone NTUA | AZ | 4,986 |
| Mariano Lake-Pinedale-Church Rock NTUA | AZ | 4,562 |
| Crownpoint-Littlewater-Three Mile Point NTUA | AZ | 3,950 |
| Ganado-Burnside-Cornfield-Steamboat NTUA | AZ | 3,947 |
| Kayenta NTUA | AZ | 3,844 |
| Toadlena NTUA | AZ | 903 |
Frequently asked questions about ZIP 86504 tap water
Is the tap water in ZIP 86504 safe to drink?
EPA testing detected 24 contaminants across the water suppliers serving ZIP 86504. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and your utility's annual Consumer Confidence Report for the official status.
Which water suppliers serve ZIP 86504?
11 public water suppliers report EPA drinking-water monitoring for ZIP 86504. Each is listed above with its population served.
What contaminants are in ZIP 86504's water?
EPA monitoring detected Nitrate, Fluoride, Barium, Nitrite, Lithium, and others across this ZIP's suppliers. The full list with levels and sources is above.