Community Water System · PWS 090400112
SCUA Lower Peridot
Operator location San Carlos, EPA Region 9 — Tribal Water Systems - smaller served population (≤ 999) at 702 people served; 503 SDWIS violations on record from groundwater sources.
- 702
- People served (this PWS)
- 503
- EPA violations (this PWS)
- 17
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
SCUA Lower Peridot standing, high SDWIS violation third
702 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 3% is middle-third health share (≤ 23%). Population rank #24,213 of 29,740 among systems serving 500+.
The verdict
SCUA Lower Peridot sits in the upper third of the sitemap cohort by violation count (503), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (702; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 3% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #24,213 of 29,740
- Population · /systems
- #105 of 129
- Population · 09
- 503
- Total EPA violations on record
- 3%
- 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
- 92
- School/Daycare
- No
- MCL Violations
- 10
- Monitoring Violations
- 376
- Treatment Tech Violations
- 7
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 119 | 2016 |
| Consumer Confidence Rule | Other | 15 | 2022 |
| Revised Total Coliform Rule | RPT | 13 | 2023 |
| Lead and Copper Rule | MR | 12 | 2013 |
| Arsenic | MR | 10 | 2024 |
| E. COLI | MR | 10 | 2022 |
| Coliform (TCR) | MCL | 9 | 2007 |
| Nitrate | MR | 6 | 2010 |
| Total Polychlorinated Biphenyls (PCB) | MR | 5 | 2008 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 5 | 2008 |
| Groundwater Rule | TT | 5 | 2024 |
| Barium | MR | 4 | 2008 |
| Cadmium | MR | 4 | 2008 |
| Chromium | MR | 4 | 2008 |
| Fluoride | MR | 4 | 2008 |
| Mercury | MR | 4 | 2008 |
| Selenium | MR | 4 | 2008 |
| BHC-GAMMA | MR | 4 | 2008 |
| Methoxychlor | MR | 4 | 2008 |
| Toxaphene | MR | 4 | 2008 |
| Atrazine | MR | 4 | 2008 |
| LASSO | MR | 4 | 2008 |
| Heptachlor | MR | 4 | 2008 |
| Heptachlor epoxide | MR | 4 | 2008 |
| 2,4-D | MR | 4 | 2008 |
| 2,4,5-TP | MR | 4 | 2008 |
| Pentachlorophenol | MR | 4 | 2008 |
| 1,2,4-Trichlorobenzene | MR | 4 | 2008 |
| cis-1,2-Dichloroethylene | MR | 4 | 2008 |
| ETHYLENE DIBROMIDE | MR | 4 | 2008 |
Violation Count vs. the National Corpus
SCUA Lower Peridot has 503 recorded EPA violations, 95% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 5% carry more. 3% of this system's own violations are health-based (17 of 503), and it ranks #24,213 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)
503 Higher than most more violations than 95% 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
Population served record for SCUA Lower Peridot
EPA SDWIS lists 702 people served and 92 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
503 violations · 702 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.
Cross-state systems with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with SCUA Lower Peridot
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 9 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 9 — Tribal Water Systems 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.