North Geraldine Water System

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: 50 people
Connections: 13
Water source: Groundwater bought from another system
Based in: Geraldine, MT
County: Chouteau
Owner: Local government

The ZIP code it serves

59446

The short answer

Nothing in EPA’s and Montana’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate: Montana’s own results, samples taken from Dec. 21, 2021 to Aug. 25, 2025.

Below EPA’s limits3

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

16ppb

Highest yearly average, 2021 to 2025

Averaged by year, the highest was 16 ppb, in 2025, below EPA’s legal limit of 80 ppb. That was also the latest year on file.

What handles it

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

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

6.2ppb

Highest yearly average, 2021 to 2025

Averaged by year, the highest was 6.2 ppb, in 2025, below EPA’s legal limit of 60 ppb. That was also the latest year on file.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.09ppm

One sample

2022, one sample: 0.09 ppm

The highest sample, in 2022, was 0.09 ppm, below EPA’s legal limit of 10 ppm. That is the only year on file, and its one sample was 0.09 ppm.

What handles it

NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.

Lead

Violations since 2016

No health-based violations on file with EPA since 2016. There are 6 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

Everything else. Total trihalomethanes (TTHM), haloacetic acids (HAA5) and nitrate results here are Montana’s own from 2021 on, with EPA’s national file for 2012 to 2019. North Geraldine Water System’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 Dec. 21, 2021 to Aug. 25, 2025.

Testing your own tap

North Geraldine Water System’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 North Geraldine Water System serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

Aqua Tech Laboratory
Lewistown, MT · about 52 miles
Certified for bacteria
(406) 538-6988

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