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Community Water System · PWS 090400096

GRIC DPW Stotonic

Operator location Sacaton, EPA Region 9 — Tribal Water Systems - upper-third violation load (> 74 violations) with 88 EPA violations; groundwater source; 2,566 served (PWS-level, not municipal population).

2,566
People served (this PWS)
88
EPA violations (this PWS)
12
Health-based (this PWS)
Untested
UCMR5 (this PWS)
Follow published updates (RSS)

GRIC DPW Stotonic standing, high SDWIS violation third

88 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 14% is middle-third health share (≤ 23%). Population rank #11,695 of 29,740 among systems serving 500+.

The verdict

GRIC DPW Stotonic sits in the upper third of the sitemap cohort by violation count (88), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 2,566 (mid served population (≤ 3,309)). Health-based share is 14% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

#11,695 of 29,740
Population · /systems
#55 of 129
Population · 09
88
Total EPA violations on record
14%
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
Community
Owner Type
Native American
Connections
732
School/Daycare
No
MCL Violations
10
Monitoring Violations
41
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 13 2008
Arsenic MCL 6 2011
Nitrate MR 5 2006
Coliform (TCR) MCL 4 2009
Mercury MR 3 2001
Lead and Copper Rule MR 3 2023
Arsenic MR 2 1996
Barium MR 2 1996
Cadmium MR 2 1996
Chromium MR 2 1996
Fluoride MR 2 1996
LEAD AND COPPER RULE REVISIONS TT 2 2024
Selenium MR 2 1996
Endothall MR 1 2001
BHC-GAMMA MR 1 2001
Total Polychlorinated Biphenyls (PCB) MR 1 2001
Consumer Confidence Rule Other 1 2001
Revised Total Coliform Rule RPT 1 2024
Diquat MR 1 2001
Xylenes, Total MR 1 2001

Violation Count vs. the National Corpus

GRIC DPW Stotonic has 88 recorded EPA violations, 70% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 29% carry more. 14% of this system's own violations are health-based (12 of 88), and it ranks #11,695 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)

88 Around the middle fewer violations than 29% 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

SDWIS compliance record for GRIC DPW Stotonic

88 violations on record for 090400096; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.

EPA SDWIS · PWS 090400096

Sources: EPA SDWIS

Nationwide peers

88 violations · 2,566 served: nearest cross-state SDWIS matches.

Cross-state systems with comparable violation load

Nearest cross-state community systems (500+ served) by total SDWIS violations on record.

4 peers

Cross-state systems near this population served

Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).

4 peers

What to do with GRIC DPW Stotonic

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

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