WEST UNION ELEM SD 1
PWS ID: OR4193774 · HILLSBORO, Oregon 97124
Population Served
350
Total Violations
123
Health-Based Violations
1
Water Source
Groundwater
System Details
- System Type
- Non-Transient Non-Community
- Owner Type
- Local
- Connections
- 1
- County
- Washington
- School/Daycare
- Yes
- MCL Violations
- 1
- Monitoring Violations
- 116
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 19 | 2013 |
| Nitrate | MR | 6 | 2010 |
| Nitrite | MR | 3 | 2002 |
| Barium | MR | 3 | 2002 |
| Chromium | MR | 3 | 2002 |
| Fluoride | MR | 3 | 2002 |
| Mercury | MR | 3 | 2002 |
| Nickel | MR | 3 | 2002 |
| Antimony, Total | MR | 3 | 2002 |
| Thallium, Total | MR | 3 | 2002 |
| Beryllium, Total | MR | 3 | 2002 |
| Selenium | MR | 3 | 2002 |
| CYANIDE | MR | 3 | 2002 |
| Cadmium | MR | 3 | 2002 |
| Revised Total Coliform Rule | MON | 2 | 2016 |
| COLIPHAGE | MR | 2 | 2012 |
| Arsenic | MR | 1 | 2002 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2002 |
| o-Dichlorobenzene | MR | 1 | 2002 |
| p-Dichlorobenzene | MR | 1 | 2002 |
| trans-1,2-Dichloroethylene | MR | 1 | 2002 |
| 1,2-Dichloroethane | MR | 1 | 2002 |
| Carbon tetrachloride | MR | 1 | 2002 |
| 1,2-Dichloropropane | MR | 1 | 2002 |
| Trichloroethylene | MR | 1 | 2002 |
| 1,1,2-Trichloroethane | MR | 1 | 2002 |
| Benzene | MR | 1 | 2002 |
| Toluene | MR | 1 | 2002 |
| Ethylbenzene | MR | 1 | 2002 |
| Styrene | MR | 1 | 2002 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.