KEYSTONE
PWS ID: SD4601082 · KEYSTONE, South Dakota 57751
Population Served
349
Total Violations
50
Health-Based Violations
14
Water Source
Groundwater
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 249
- County
- Pennington
- School/Daycare
- No
- MCL Violations
- 14
- Monitoring Violations
- 33
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 14 | 2015 |
| Lead and Copper Rule | MR | 3 | 2010 |
| Gross Alpha, Excl. Radon and U | MR | 3 | 2019 |
| Barium | MR | 3 | 1989 |
| Chromium | MR | 3 | 1989 |
| Mercury | MR | 3 | 1989 |
| Fluoride | MR | 3 | 1989 |
| Cadmium | MR | 3 | 1989 |
| Combined Uranium | MR | 3 | 2019 |
| Selenium | MR | 3 | 1989 |
| Combined Radium (-226 and -228) | MR | 3 | 2019 |
| Arsenic | MR | 3 | 1989 |
| Consumer Confidence Rule | Other | 2 | 2000 |
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025.
This data is provided for informational purposes only.