HARDIN KOA CISTERN
Montana — Transient Non-Community — PWSID: MT0002008
System Information
| PWSID | MT0002008 |
| System Name | HARDIN KOA CISTERN |
| System Type | Transient Non-Community |
| Water Source | Surface Water Purchased |
| Activity Status | Active |
| Owner Type | Private |
| EPA Region | 08 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Feb 2, 1981 |
| Last Reported | Mar 26, 2026 |
Location & Contact
| State | Montana |
| City | HARDIN |
| ZIP Code | 59034 |
| Address | RR1 Box 100A |
| Organization | MASTIN, KRISTY |
| Phone | 406-665-1635 |
Population & Service
| Population Served | 100 |
| Service Connections | 49 |
Drinking Water Violations (45)
This water system has 45 violations recorded in the EPA SDWIS database.
| Begin Date | End Date | Contaminant | Category | Health-Based | Major | Measured | Federal MCL | State MCL | Status | Return to Compliance | Rule |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan 17, 2026 | — | TT | Yes | No | — | — | — | Addressed | — | — | |
| Jan 17, 2026 | — | TT | Yes | No | — | — | — | Addressed | — | — | |
| Jan 17, 2026 | — | TT | Yes | No | — | — | — | Addressed | — | — | |
| Jan 17, 2026 | — | TT | Yes | No | — | — | — | Addressed | — | — | |
| Oct 1, 2025 | Oct 31, 2025 | MON | No | Yes | — | — | — | Archived | Oct 31, 2025 | — | |
| Oct 1, 2025 | Oct 31, 2025 | MON | No | Yes | — | — | — | Archived | Oct 31, 2025 | — | |
| Oct 1, 2025 | Oct 31, 2025 | MON | No | Yes | — | — | — | Archived | Oct 31, 2025 | — | |
| Oct 1, 2025 | Oct 31, 2025 | MON | No | Yes | — | — | — | Archived | Oct 31, 2025 | — | |
| Sep 1, 2024 | Sep 30, 2024 | MON | No | Yes | — | — | — | Archived | Sep 30, 2024 | — | |
| Sep 1, 2024 | Sep 30, 2024 | MON | No | Yes | — | — | — | Archived | Sep 30, 2024 | — | |
| Sep 1, 2024 | Sep 30, 2024 | MON | No | Yes | — | — | — | Archived | Sep 30, 2024 | — | |
| Sep 1, 2024 | Sep 30, 2024 | MON | No | Yes | — | — | — | Archived | Sep 30, 2024 | — | |
| Jul 1, 2024 | Jul 31, 2024 | MON | No | Yes | — | — | — | Archived | Jul 31, 2024 | — | |
| Jul 1, 2024 | Jul 31, 2024 | MON | No | Yes | — | — | — | Archived | Jul 31, 2024 | — | |
| Jul 1, 2024 | Jul 31, 2024 | MON | No | Yes | — | — | — | Archived | Jul 31, 2024 | — | |
| Jul 1, 2024 | Jul 31, 2024 | MON | No | Yes | — | — | — | Archived | Jul 31, 2024 | — | |
| Feb 1, 2024 | Feb 29, 2024 | MON | No | Yes | — | — | — | Archived | Feb 29, 2024 | — | |
| Feb 1, 2024 | Feb 29, 2024 | MON | No | Yes | — | — | — | Archived | Feb 29, 2024 | — | |
| Feb 1, 2024 | Feb 29, 2024 | MON | No | Yes | — | — | — | Archived | Feb 29, 2024 | — | |
| Feb 1, 2024 | Feb 29, 2024 | MON | No | Yes | — | — | — | Archived | Feb 29, 2024 | — | |
| Feb 1, 2024 | Feb 29, 2024 | MON | No | Yes | — | — | — | Archived | Feb 29, 2024 | — | |
| Apr 1, 2017 | Apr 30, 2017 | MON | No | Yes | — | — | — | Resolved | Apr 30, 2017 | — | |
| Apr 1, 2017 | Apr 30, 2017 | MON | No | Yes | — | — | — | Resolved | Apr 30, 2017 | — | |
| Apr 1, 2017 | Apr 30, 2017 | MON | No | Yes | — | — | — | Resolved | Apr 30, 2017 | — | |
| Oct 1, 2006 | Oct 31, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Oct 31, 2006 | — | |
| Oct 1, 2006 | Oct 31, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Oct 31, 2006 | — | |
| Oct 1, 2006 | Oct 31, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Oct 31, 2006 | — | |
| Oct 1, 2006 | Oct 31, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Oct 31, 2006 | — | |
| Jul 1, 2006 | Jul 31, 2006 | MCL | Yes | No | — | 5% of samples | — | Resolved | Jul 31, 2006 | — | |
| Jul 1, 2006 | Jul 31, 2006 | MCL | Yes | No | — | 5% of samples | — | Resolved | Jul 31, 2006 | — | |
| Jul 1, 2006 | Jul 31, 2006 | MCL | Yes | No | — | 5% of samples | — | Resolved | Jul 31, 2006 | — | |
| Jul 1, 2006 | Jul 31, 2006 | MCL | Yes | No | — | 5% of samples | — | Resolved | Jul 31, 2006 | — | |
| Jul 1, 2006 | Jul 31, 2006 | MCL | Yes | No | — | 5% of samples | — | Resolved | Jul 31, 2006 | — | |
| Jun 1, 2006 | Jun 30, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 2006 | — | |
| Jun 1, 2006 | Jun 30, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 2006 | — | |
| Jun 1, 2006 | Jun 30, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 2006 | — | |
| Jun 1, 2006 | Jun 30, 2006 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 2006 | — | |
| Jun 1, 1994 | Jun 30, 1994 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 1994 | — | |
| Jun 1, 1994 | Jun 30, 1994 | MR | No | No | — | 5% of samples | — | Resolved | Jun 30, 1994 | — | |
| Oct 1, 1983 | Sep 30, 1984 | MR | No | Yes | — | 10 mg/L | — | Archived | Sep 30, 1984 | — | |
| Oct 1, 1982 | Sep 30, 1983 | MR | No | Yes | — | 10 mg/L | — | Archived | Sep 30, 1983 | — | |
| Oct 1, 1981 | Sep 30, 1982 | MR | No | Yes | — | 10 mg/L | — | Archived | Sep 30, 1982 | — | |
| Jan 1, 1981 | Jan 31, 1981 | MR | No | Yes | — | 10 mg/L | — | Archived | Jan 31, 1981 | — | |
| — | — | — | No | No | — | — | — | — | — | — | |
| — | — | — | No | No | — | — | — | — | — | — |
About This Water System
Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.