Tapcensus

Big Stack Estates

Community water system in Great Falls, Cascade County, Montana, serving 60 people from surface water purchased. 1 rule violated in the past three years. Privately owned.

People served 60 surface water purchased
Rules violated, past 3 years 1 one rule can carry several violations
Unresolved 0 rules still in violation, EPA data updated Oct 7, 2026
Quarters with violations 1 of the last 12 quarters

Quarterly compliance history

–Q3
2023
VQ4
2023
–Q1
2024
–Q2
2024
–Q3
2024
–Q4
2024
–Q1
2025
–Q2
2025
–Q3
2025
–Q4
2025
–Q1
2026
–Q2
2026
–Q3
2026
–No violation identified VViolation identified SSerious violator (EPA enforcement priority) UUndetermined Oldest quarter on the left. Quarters 1 to 12 are the twelve most recent official quarters at EPA's last data refresh; the 13th is the quarter in progress at that refresh, which EPA reports as undetermined.

Rules violated in the past three years

Jul to Sep 2023 to Jul to Sep 2026

Long Term 2 Enhanced Surface Water Treatment Rule

Monitoring and Reporting

1 violation, Dec 2023 to Feb 2024
EPA rule code 123 · 1 violation recorded

Monitoring and Reporting: 1 violation, Dec 2023 to Feb 2024. The system did not complete required monitoring, or did not report the results on time. This does not show that a contaminant was found.

What the rule requires: The LT2 ESWTR (2006) required all surface water and GWUDI systems to monitor source water for Cryptosporidium, then apply additional treatment based on measured concentrations. Higher-bin systems (more oocysts detected) must install advanced treatment — UV disinfection, ozone, or membrane filtration — beyond the original SWTR requirements.

About this rule
About this data

Rules violated and the list above come from EPA's SDWIS violation records, one row per violation and contaminant, grouped by the rule each row belongs to. A violation counts when its non-compliance period ended on or after Jul 1, 2023, the start of the thirteen quarters ECHO's three-year figures cover, or is still open; it is unresolved when it was still open at EPA's data refresh on Oct 7, 2026. EPA's rule code 500, "Not Regulated", is left out, as in ECHO's counts. Each rule's violation count is EPA's, and one rule can carry several: a missed monitoring round for a group of contaminants is one violation per contaminant and period. Category names are EPA's violation categories.

ECHO's own summary count of rules violated agrees with this grouping for 98.8% of active systems nationally, and its count of rules being violated for 98.7%; where they differ, the figures here follow the rows listed.

Measured contaminant levels are not part of this record; each system publishes them in its annual Consumer Confidence Report.

The system's location is the centre of the first town EPA lists the system as serving, from Census Bureau place files.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Montana records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.