MNIHNAPA WATER SYSTEM

HARLEM, MT · ~220 people served

Check your exact address → HARLEM overview

100

Excellent

PurityRadar safety score

PWSID

083090047

State

Montana

City

HARLEM

Population served

220

Primary source

Groundwater

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

No PFAS detections are on record for this system from EPA’s UCMR5 monitoring (2023–25). Absence of a detection isn’t a guarantee — not every system was sampled, and this dataset doesn’t cover other contaminants.

Violations & enforcement

138

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Dec 2021. Official EPA record →

Monitoring & reporting · Uranium began Jan 2021 Resolved

Monitoring & reporting · EPA contaminant 4020 began Jan 2021 Resolved

Monitoring & reporting · Gross alpha began Jan 2021 Resolved

Monitoring & reporting · EPA contaminant 4030 began Jan 2021 Resolved

Monitoring & reporting · Combined radium-226/228 began Jan 2021 Resolved

Monitoring & reporting · EPA contaminant 4020 began Oct 2020 Resolved

Monitoring & reporting · EPA contaminant 4030 began Oct 2020 Resolved

Monitoring & reporting · Gross alpha began Oct 2020 Resolved

Monitoring & reporting · Combined radium-226/228 began Oct 2020 Resolved

Monitoring & reporting · Uranium began Oct 2020 Resolved

Monitoring & reporting · EPA contaminant 3014 began Aug 2020 Resolved

Monitoring & reporting · Lead & Copper Rule began Jul 2020 Resolved

Recent enforcement actions

State action · SOX Dec 2021
State action · SOX May 2021
State action · SOX Feb 2021
State action · SOX Sep 2020
State action · SOX Sep 2020
State action · SOX Feb 2020
State action · SOX Oct 2019
State action · SOX Oct 2019

Area water-quality monitoring

Environmental monitoring (rivers, wells, intakes) recorded in this system’s service area in the EPA/USGS Water Quality Portal since 2018 — source/ambient water, not finished tap water. Context for the watershed, not a reading from your tap.

ContaminantMedian · max · samples

Arsenic

1 station · latest Sep 2023

0.00085 · max 0.0015 mg/L · 18

Copper

1 station · latest Jun 2023

0.0025 · max 0.003 mg/L · 2

Lead

1 station · latest May 2023

0.0003 · max 0.0003 mg/L · 1

Source: Water Quality Portal (EPA/USGS/state agencies). Values are as-reported and aren’t health thresholds.

This profile is built from EPA public records for system 083090047 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.