Public water system · MT0004251
ActiveSonju Industrial Inc.
At a glance
Sonju Industrial Inc. (PWSID MT0004251) is an active non-transient non-community water system in Flathead County, Montana. It reports serving 70 people through 2 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
70
Service connections
2
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Sonju Industrial Inc. compare with other water systems in Flathead County?
By EPA's size categories, Sonju Industrial Inc. is a very small system (500 people or fewer). Flathead County has 327 active public water systems. Its population served is well below the county average of 324 people per system, and accounts for less than 0.1% of the 105,781 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Sonju Industrial Inc. is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Montana has 319 active non-transient non-community water systems, 13% of the state's 2,378 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,994 Montana systems (84%) list groundwater as their primary source.
Who owns and regulates Sonju Industrial Inc.?
EPA lists Sonju Industrial Inc. as privately owned. The MT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 263 of the 327 active systems in Flathead County (80%) are also privately owned.
Does Sonju Industrial Inc. have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2020. The violations listed here began between July 2014 and June 2020. By type: 11 monitoring and reporting and 1 monitoring. The contaminants or rules involved are Revised Total Coliform Rule, Lead and Copper Rule, Heptachlor and Simazine. EPA lists 12 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2020-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2014-09-29 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Heptachlorcode 2065 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Simazinecode 2037 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbofurancode 2046 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Alachlor (Lasso)code 2051 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Lindane (gamma-BHC)code 2010 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) adipatecode 2035 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Oxamylcode 2036 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Aldicarb sulfonecode 2044 | No | Resolved |
| 2014-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Methoxychlorcode 2015 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Sonju Industrial Inc.: frequently asked questions
Who runs Sonju Industrial Inc.?
Sonju Industrial Inc. (PWSID MT0004251) is a non-transient non-community water system privately owned. It is regulated by the MT state drinking water program.
How many people does Sonju Industrial Inc. serve?
Sonju Industrial Inc. reports serving 70 people through 2 service connections in Flathead County, Montana.
Where does Sonju Industrial Inc. get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Sonju Industrial Inc. have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2020. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Sonju Industrial Inc.'s water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2020. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Sonju Industrial Inc.'s water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Sonju Industrial Inc. is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Flathead County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Kalispell Public Works | Flathead | 25,000 | Community | Groundwater |
| Whitefish City of | Flathead | 10,418 | Community | Surface water |
| Flathead County Water and Sewer | Flathead | 7,775 | Community | Groundwater |
| Bigfork County Water and Sewer | Flathead | 6,100 | Community | Groundwater |
| Columbia Falls City of | Flathead | 4,450 | Community | Groundwater |
| Ridge Run | Flathead | 3,500 | Transient non-community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Sonju Industrial Inc., PWSID MT0004251, Montana”, https://aquacensus.com/water-systems/montana/sonju-industrial-inc-mt0004251 (data as of October 1, 2026).