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Non-Transient Non-Community Water System · PWS MT0004796

Rocky Mountain College

Operator location Billings, Montana - 0% of 9 violations are health-based (lower-third health share (≤ 1%)); surface water source; 5,700 served per SDWIS.

5,700
People served (this PWS)
9
EPA violations (this PWS)
0
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Rocky Mountain College standing, low SDWIS violation third

0% of 9 recorded violations are health-based - lower-third health share (≤ 1%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 0% is lower-third health share (≤ 1%). UCMR5: UCMR5 tested, none detected. Population rank #7,071 of 29,740 among systems serving 500+.

The verdict

Rocky Mountain College is in the lower third by violation count (9; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is large (5,700; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is only 0% - almost all of this trail is monitoring or reporting. UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#7,071 of 29,740
Population · /systems
#24 of 283
Population · MT
9
Total EPA violations on record
0%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Non-Transient Non-Community
Owner Type
Private
Connections
17
County
Yellowstone
School/Daycare
Yes
MCL Violations
0
Monitoring Violations
9
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 9 2012

Violation Count vs. the National Corpus

Rocky Mountain College has 9 recorded EPA violations, 17% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 82% carry more. 0% of this system's own violations are health-based (0 of 9), and it ranks #7,071 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

9 Among the lowest violation counts fewer violations than 82% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFTrDA 8/20/2024 <7.00 ppt 7.00 ppt Not Detected
PFTA 8/20/2024 <8.00 ppt 8.00 ppt Not Detected
NEtFOSAA 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 8/20/2024 <6.00 ppt 6.00 ppt Not Detected
ADONA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 8/20/2024 <4.00 ppt 4.00 ppt Not Detected
11Cl-PF3OUdS 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
PFEESA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 8/20/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
PFHxS 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 8/20/2024 <20.00 ppt 20.00 ppt Not Detected
HFPO-DA 8/20/2024 <5.00 ppt 5.00 ppt Not Detected
PFHpA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 8/20/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/20/2024 <4.00 ppt 4.00 ppt Not Detected
PFOA 8/20/2024 <4.00 ppt 4.00 ppt Not Detected
PFDA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 8/20/2024 <2.00 ppt 2.00 ppt Not Detected
9Cl-PF3ONS 8/20/2024 <2.00 ppt 2.00 ppt Not Detected
PFBS 8/20/2024 <3.00 ppt 3.00 ppt Not Detected
PFTA 5/14/2024 <8.00 ppt 8.00 ppt Not Detected
NMeFOSAA 5/14/2024 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 5/14/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 5/14/2024 <7.00 ppt 7.00 ppt Not Detected
9Cl-PF3ONS 5/14/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 5/14/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 5/14/2024 <2.00 ppt 2.00 ppt Not Detected
PFHxA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 5/14/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 5/14/2024 <4.00 ppt 4.00 ppt Not Detected
PFNA 5/14/2024 <4.00 ppt 4.00 ppt Not Detected
ADONA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFEESA 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxS 5/14/2024 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 5/14/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 5/14/2024 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 5/14/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 5/14/2024 <3.00 ppt 3.00 ppt Not Detected

Health-based violations on Rocky Mountain College

0 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for MT0004796.

Sources: EPA SDWIS

Nationwide peers

9 violations · 5,700 served: nearest cross-state SDWIS matches.

What to do with Rocky Mountain College

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in Montana compares on the same EPA violation measures. Montana systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater