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Tap water quality report

Rosemarys Addition

EPA monitoring tested this supplier for 65 contaminants and detected 10. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

65
contaminants tested
10
detected
30
people served
0
health-based violations
Montana rankingsLead in MontanaPFAS in Montana
Water source
Ground water
Ownership
Private
Counties served
Lewis and Clark

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

0
health-based violations
111
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Resolved 2014-10-01
MR Monitoring Resolved 2014-10-01
MR Monitoring Resolved 2014-10-01
MR Monitoring Resolved 2012-01-01 → 2012-12-31
MR Monitoring Resolved 2012-01-01 → 2012-12-31
MR Monitoring Resolved 2012-01-01 → 2012-12-31
Other Monitoring Resolved 2007-02-05
Other Monitoring Resolved 2007-02-05
MR Monitoring Resolved 2004-10-01
MR Monitoring Resolved 2004-10-01

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate-Nitrite
4510 µg/L 45%
of the EPA limit 10000 µg/L
 14/14 SYR4 2013–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 11/11 LCR 2024
Copper
204 µg/L 16%
of the EPA limit 1300 µg/L
 10/10 SYR4 2015–2018
Lead
2 µg/L 13%
of the EPA limit 15 µg/L
 5/10 SYR4 2015–2018
Arsenic
2 µg/L 20%
of the EPA limit 10 µg/L
 3/3 SYR4 2013–2019
Barium
76 µg/L 3.8%
of the EPA limit 2000 µg/L
 1/1 SYR4 2013
Combined Radium (-226 And -228)
0.7000 pCi/L 14%
of the EPA limit 5 pCi/L
 1/1 SYR4 2013
Di(2-ethylhexyl) Phthalate
2.18 µg/L 36%
of the EPA limit 6 µg/L
 1/3 SYR4 2013–2019
Gross Alpha, Excl. Radon And U
3.8 pCi/L 25%
of the EPA limit 15 pCi/L
 1/1 SYR4 2013
Selenium
2 µg/L 4%
of the EPA limit 50 µg/L
 1/1 SYR4 2013
55 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DAntimony, TotalAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalBromodichloromethaneBromoformChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChloroformChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDibromochloromethaneDinosebEndrinEthylbenzeneFluorideHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorOxamylPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
CADWELL, LORI K
Phone
406-458-9818

Frequently asked questions about Rosemarys Addition

Is Rosemarys Addition tap water safe to drink?

EPA monitoring detected 10 contaminants in Rosemarys Addition's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Rosemarys Addition's water?

EPA monitoring detected Nitrate-Nitrite, Lead, Copper, Lead, Arsenic, and others. The full list with the level and data source for each is above.

How many people does Rosemarys Addition serve?

Rosemarys Addition reports serving 30 people in Montana, per its EPA record.

Has Rosemarys Addition had any water quality violations?

The EPA has 111 violations on file for Rosemarys Addition, of which 0 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.