WEST YELLOWSTONE TOWN OF
PWS ID: MT0003136 · WEST YELLOWSTONE, Montana 59758
PFAS Detected
1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
Population Served
9,899
Total Violations
203
Health-Based Violations
4
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 628
- County
- Gallatin
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 189
- Treatment Tech Violations
- 3
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 27 | 2014 |
| Arsenic | MR | 15 | 2021 |
| E. COLI | MR | 13 | 2019 |
| Fluoride | MR | 13 | 2021 |
| Consumer Confidence Rule | Other | 10 | 2017 |
| Lead and Copper Rule | MR | 7 | 2018 |
| Hexachlorocyclopentadiene | MR | 7 | 2017 |
| Revised Total Coliform Rule | MON | 6 | 2016 |
| Endrin | MR | 4 | 2017 |
| BHC-GAMMA | MR | 4 | 2017 |
| Methoxychlor | MR | 4 | 2017 |
| Di(2-ethylhexyl) adipate | MR | 4 | 2017 |
| Simazine | MR | 4 | 2017 |
| Di(2-ethylhexyl) phthalate | MR | 4 | 2017 |
| Carbofuran | MR | 4 | 2017 |
| Atrazine | MR | 4 | 2017 |
| Heptachlor | MR | 4 | 2017 |
| 2,4-D | MR | 4 | 2017 |
| 2,4,5-TP | MR | 4 | 2017 |
| HEXACHLOROBENZENE | MR | 4 | 2017 |
| Benzo(a)pyrene | MR | 4 | 2017 |
| Dalapon | MR | 4 | 2017 |
| Heptachlor epoxide | MR | 4 | 2017 |
| LASSO | MR | 4 | 2017 |
| Pentachlorophenol | MR | 4 | 2017 |
| Toxaphene | MR | 4 | 2017 |
| Chlordane | MR | 4 | 2017 |
| Dinoseb | MR | 4 | 2017 |
| OXAMYL | MR | 4 | 2017 |
| Picloram | MR | 4 | 2017 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 6 of 180 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFBS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 6:2 FTS | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 8:2 FTS | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFBA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| HFPO-DA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| ADONA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 4:2 FTS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFNA | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOA | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| NMeFOSAA | 4/23/2024 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| PFDoA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFUnA | 4/23/2024 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| 11Cl-PF3OUdS | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFDA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFMBA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFEESA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| NFDHA | 4/23/2024 | <0.02 µg/L | 0.02 µg/L | Not Detected |
| 9Cl-PF3ONS | 4/23/2024 | <0.002 µg/L | 0.002 µg/L | Not Detected |
| lithium | 4/23/2024 | 15.0000 µg/L | 9 µg/L | Detected |
| PFTA | 4/23/2024 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| NEtFOSAA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFTrDA | 4/23/2024 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| PFMPA | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFPeS | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFTA | 4/23/2024 | <0.008 µg/L | 0.008 µg/L | Not Detected |
| PFTrDA | 4/23/2024 | <0.007 µg/L | 0.007 µg/L | Not Detected |
| NEtFOSAA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| NMeFOSAA | 4/23/2024 | <0.006 µg/L | 0.006 µg/L | Not Detected |
| lithium | 4/23/2024 | 66.0000 µg/L | 9 µg/L | Detected |
| PFDoA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| HFPO-DA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFBS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHpA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFHxS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFNA | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOS | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFDA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFBA | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 6:2 FTS | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| 4:2 FTS | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| 8:2 FTS | 4/23/2024 | <0.005 µg/L | 0.005 µg/L | Not Detected |
| PFHxA | 4/23/2024 | <0.003 µg/L | 0.003 µg/L | Not Detected |
| PFPeS | 4/23/2024 | <0.004 µg/L | 0.004 µg/L | Not Detected |
| PFOA | 4/23/2024 | <0.004 µg/L | 0.004 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.