Skip to content
TapBuff
ZIP

St Labre Indian School

What EPA’s and Montana’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
650 people
Connections
98
Water source
Groundwater
Based in
Ashland, MT
County
Rosebud
Owner
Private
Hardness
Varies by source
The ZIP code it serves

59003

The short answer

1 result is above EPA’s legal limit, and 2 more are above the health goal. The worst: Total trihalomethanes (TTHM), above the legal limit. 39 health-based violations since 2016.

What handles it

What was found

Lead and copper: EPA SDWIS monitoring periods ending 2007 to 2025.

Total trihalomethanes (TTHM), uranium, fluoride, haloacetic acids (HAA5), nitrate, arsenic and chromium (total): Montana’s own results, samples taken from March 17, 2020 to Sept. 23, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Above the legal limit

90ppb

Highest yearly average, 2020 to 2026

2026 average: 13.2 ppb

Averaged by year, the highest was 90 ppb, in 2021, above EPA’s legal limit of 80 ppb. Its highest single sample was 132 ppb. In 2026, the latest year on file, its eight samples averaged 13.2 ppb. EPA recorded violations for total trihalomethanes (TTHM) at this utility in 2021, 2022, 2023, 2024 and 2025. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 145 ppb, in 2014, and EPA recorded violations in 2015, 2017, 2018 and 2019.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Above the health goal2

Lead

Comes from pipes, often your own

Above the health goal

1.0ppb

90th percentile, 2023 to 2025

In the latest period, 9 in 10 homes sampled were at or below 1.0 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Uranium

Comes from the source

Above the health goal

1.1ppb

Highest yearly average, 2024

Averaged by year, the highest was 1.1 ppb, in 2024: below EPA’s legal limit of 30 ppb, but above its health goal of zero. That is the only year on file.

What handles it

Below EPA’s limits3

Fluoride

Forms or is added in treatment

Below EPA’s limits

2.1ppm

Highest yearly average, 2023 to 2025

Averaged by year, the highest was 2.1 ppm, in 2025, below EPA’s legal limit of 4.0 ppm. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 1.9 ppm, in 2019.

What handles it

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

18ppb

Highest yearly average, 2020 to 2026

2026 average: 2.0 ppb

Averaged by year, the highest was 18 ppb, in 2021, below EPA’s legal limit of 60 ppb. Its highest single sample was 21 ppb. In 2026, the latest year on file, its eight samples averaged 2.0 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 31.2 ppb, in 2014.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.03ppm

Highest sample; found in 3 of 7

2026: not found

The highest sample, in 2025, was 0.03 ppm, below EPA’s legal limit of 10 ppm. In 2026, the latest year on file, it wasn’t found in its one sample. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.38 ppm, in 2017.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Chromium (total)

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claims: Trihalomethanes (TTHM) Reduction, Lead Reduction

    For: Total trihalomethanes (TTHM), Lead

    Other certifiers’ wording: VOC Reduction

  • NSF/ANSI 58

    Claims: Trihalomethanes (TTHM) Reduction, Lead Reduction, Uranium

    For: Total trihalomethanes (TTHM), Lead, Uranium

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best water filters for lead, ranked

Hardness

Hard to very hard depending on the source, 158 to 298 mg/L (9.3 to 17.4 grains per gallon), across 2 sampling points, 2015 to 2025.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared, salt includedSoftener or salt-free conditioner?Montana water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2025 to Dec. 31, 20250.083 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2024 to Sept. 30, 202483 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2024 to June 30, 20240.082 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2024 to March 31, 20240.092 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2023 to Dec. 31, 20230.086 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2023 to Sept. 30, 20230.082 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2023 to June 30, 20230.082 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2022 to Sept. 30, 20220.087 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2022 to June 30, 20220.095 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2022 to March 31, 20220.09 MG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2021 to Dec. 31, 202190 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2021 to Sept. 30, 202188 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2021 to June 30, 202184.3 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Dec. 1, 2019 to Dec. 31, 2019—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Oct. 1, 2019 to Oct. 31, 2019—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2019 to Sept. 30, 2019105 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)July 1, 2019 to July 31, 2019—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)June 1, 2019 to June 30, 2019—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)April 1, 2019 to April 30, 2019—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2019 to June 30, 2019110 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)March 1, 2019 to March 31, 2019—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Feb. 1, 2019 to Feb. 28, 2019—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Jan. 1, 2019 to Jan. 31, 2019—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2019 to March 31, 2019107 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2018 to Dec. 31, 2018118 UG/LResolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2018 to Sept. 30, 201892 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)May 1, 2018 to May 31, 2018—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2018 to June 30, 201884 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Jan. 1, 2018 to Jan. 31, 2018—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJan. 1, 2018 to March 31, 201882.3 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Nov. 1, 2017 to Nov. 30, 2017—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageOct. 1, 2017 to Dec. 31, 201793 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Sept. 1, 2017 to Sept. 30, 2017—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageJuly 1, 2017 to Sept. 30, 2017102 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)June 1, 2017 to June 30, 2017—Resolved
TTHMThe running average was above the legal limit.EPA: Maximum Contaminant Level Violation, AverageApril 1, 2017 to June 30, 201782.8 UG/LResolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)Sept. 1, 2016 to Sept. 30, 2016—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)May 1, 2016 to May 31, 2016—Resolved
Groundwater RuleRequired treatment for surface water or groundwater was not met.EPA: Treatment Technique (SWTR and GWR)March 1, 2016 to March 31, 2016—Resolved
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 70 monitoring or reporting violations not shown.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), uranium, fluoride, haloacetic acids (HAA5), nitrate, arsenic and chromium (total) results here are Montana’s own from 2020 on, with EPA’s national file for 2012 to 2019. St Labre Indian School’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Montana’s results run from March 17, 2020 to Sept. 23, 2026.

Testing your own tap

St Labre Indian School’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Montana certifies.

The lab Montana certifies closest to the area St Labre Indian School serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • PACE Analytical-Sheridan

    Sheridan, WY · about 52 miles

    Certified for bacteria, minerals and other inorganics, organic chemicals

    (307) 672-8945

Montana State Environmental Laboratory: Private well testing packages for bacteria, metals, nutrients, anions, organic chemicals and more, open to the public. Samples can be mailed, sent by the lab's free courier, or dropped off at the lab. Environmental Laboratory, Montana Department of Public Health and Human Services.

All 36 certified labs for Montana

Sources

PWSID MT0000018. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Nearby

All Montana utilities

What to do next