Community Water System · PWS 090400114
SCUA Upper Seven Mile
San Carlos, EPA Region 9 — Tribal Water Systems 85550 - drinking water served from groundwater sources to 8,478 people, tracked in EPA SDWIS and UCMR5.
- 8,478
- People served
- 659
- EPA violations
- 89
- Health-based
- 1 PFAS
- UCMR5 result
The verdict
EPA records 659 drinking-water violations at SCUA Upper Seven Mile, 14% of them health-based, and UCMR5 testing detected 1 PFAS compound.
- 659
- Total EPA violations on record
- 14%
- Health-based (MCL / treatment failure)
- 8,478
- People served by this system
- 1
- PFAS compounds detected (UCMR5)
Water Quality Snapshot: SCUA Upper Seven Mile
SCUA Upper Seven Mile is a native american-owned community water system that delivers drinking water to 8,478 residents in San Carlos, EPA Region 9 — Tribal Water Systems through 1,776 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 659 total violations for this system , of which 89 (14%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 443 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.
The most frequently cited contaminant at this system is Coliform (TCR), recorded in 146 violations (MR). Under EPA's UCMR5 PFAS monitoring program, 1 PFAS compound was detected in samples collected from this system, with a maximum reported concentration of 53.8 ppt (parts per trillion). PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.
EPA Region 9 — Tribal Water Systems has thousands of regulated public water systems tracked by EPA under the Safe Drinking Water Act.
All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.
1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 1,776
- School/Daycare
- No
- MCL Violations
- 72
- Monitoring Violations
- 443
- Treatment Tech Violations
- 17
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 146 | 2016 |
| Public Notice | Other | 52 | 2024 |
| Coliform (TCR) | MCL | 37 | 2016 |
| Arsenic | MR | 35 | 2024 |
| E. COLI | MR | 30 | 2022 |
| Arsenic | MCL | 27 | 2016 |
| Consumer Confidence Rule | Other | 17 | 2022 |
| Gross Alpha, Excl. Radon and U | MR | 12 | 2024 |
| Groundwater Rule | TT | 12 | 2023 |
| Revised Total Coliform Rule | RPT | 12 | 2023 |
| Chlorine | MR | 11 | 2025 |
| Nitrate | MR | 10 | 2019 |
| Combined Uranium | MR | 10 | 2024 |
| Combined Radium (-226 and -228) | MR | 10 | 2024 |
| Revised Total Coliform Rule | MCL | 8 | 2023 |
| Revised Total Coliform Rule | MON | 8 | 2024 |
| Total Polychlorinated Biphenyls (PCB) | MR | 5 | 2024 |
| Revised Total Coliform Rule | TT | 5 | 2023 |
| Lead and Copper Rule | MR | 5 | 2008 |
| BHC-GAMMA | MR | 4 | 2024 |
| Methoxychlor | MR | 4 | 2024 |
| Toxaphene | MR | 4 | 2024 |
| Carbofuran | MR | 4 | 2024 |
| Atrazine | MR | 4 | 2024 |
| LASSO | MR | 4 | 2024 |
| Heptachlor | MR | 4 | 2024 |
| Heptachlor epoxide | MR | 4 | 2024 |
| 2,4-D | MR | 4 | 2024 |
| 2,4,5-TP | MR | 4 | 2024 |
| Pentachlorophenol | MR | 4 | 2024 |
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 8 of 232 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| PFBA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFMBA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 7/8/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 4:2 FTS | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NMeFOSAA | 7/8/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFHpS | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 7/8/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| NEtFOSAA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 7/8/2025 | 29.70 ppt | 3.00 ppt | Detected |
| PFHxS | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 7/8/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFOA | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFHxA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 7/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFPeA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOA | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDoA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NEtFOSAA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOS | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFNA | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTrDA | 7/8/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| NMeFOSAA | 7/8/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFHxA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 7/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 9Cl-PF3ONS | 7/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| ADONA | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeS | 7/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFTA | 7/8/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| 6:2 FTS | 7/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBS | 7/8/2025 | 25.10 ppt | 3.00 ppt | Detected |
| PFHpS | 7/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
Verify This Water System
The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for SCUA Upper Seven Mile.
EPA SDWIS, Federal Reports
EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:
View PWS ID 090400114 on SDWISSource: EPA SDWIS Federal Reports Search
EPA Region 9 — Tribal Water Systems Drinking Water Authority
EPA Region 9 — Tribal Water Systems's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.
Find 09 regulator via EPA SDWISViolation Timeline
Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.
| Year (latest) | Contaminant | Category | Count | EPA Record |
|---|---|---|---|---|
| 2025 | Chlorine | MR | 11 | SDWIS / 090400114 / 0999 |
| 2024 | Public Notice | Other | 52 | SDWIS / 090400114 / 7500 |
| 2024 | Arsenic | MR | 35 | SDWIS / 090400114 / 1005 |
| 2024 | Gross Alpha, Excl. Radon and U | MR | 12 | SDWIS / 090400114 / 4000 |
| 2024 | Combined Uranium | MR | 10 | SDWIS / 090400114 / 4006 |
| 2024 | Combined Radium (-226 and -228) | MR | 10 | SDWIS / 090400114 / 4010 |
| 2024 | Revised Total Coliform Rule | MON | 8 | SDWIS / 090400114 / 8000 |
| 2024 | Total Polychlorinated Biphenyls (PCB) | MR | 5 | SDWIS / 090400114 / 2383 |
| 2024 | BHC-GAMMA | MR | 4 | SDWIS / 090400114 / 2010 |
| 2024 | Methoxychlor | MR | 4 | SDWIS / 090400114 / 2015 |
| 2024 | Toxaphene | MR | 4 | SDWIS / 090400114 / 2020 |
| 2024 | Carbofuran | MR | 4 | SDWIS / 090400114 / 2046 |
| 2024 | Atrazine | MR | 4 | SDWIS / 090400114 / 2050 |
| 2024 | LASSO | MR | 4 | SDWIS / 090400114 / 2051 |
| 2024 | Heptachlor | MR | 4 | SDWIS / 090400114 / 2065 |
How SCUA Upper Seven Mile Compares
Cross-reference this system's record against state averages and the federal MCL framework for context.
| Metric | SCUA Upper Seven Mile | EPA Region 9 — Tribal Water Systems avg | Federal benchmark |
|---|---|---|---|
| Total violations | 659 | - | SDWA compliance, any non-zero count is a recorded breach |
| Health-based violations | 89 | - | Indicates a contaminant exceeded a federal MCL |
| PFAS detection | 1 compound | - | EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt |
| Population served | 8,478 | - | Sizing context for compliance burden |
Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across all regulated public water systems in EPA Region 9 — Tribal Water Systems.
Federal MCL reference, Safe Drinking Water Act thresholds ▼
| Contaminant | Federal MCL / Action Level | Note |
|---|---|---|
| Lead | 0 mg/L (Action Level: 0.015 mg/L) | Lead and Copper Rule treatment technique |
| Arsenic | 0.010 mg/L (10 ppb) | Health-based MCL since 2006 |
| Total Coliform | Treatment technique (RTCR) | Indicator organism, monitoring trigger |
| PFOA / PFOS (PFAS) | 4.0 ppt each (final 2024 rule) | Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026) |
| Nitrate (as N) | 10 mg/L | Acute health risk for infants |
Frequently Asked Questions
Is SCUA Upper Seven Mile water safe to drink? ▼
How many people does SCUA Upper Seven Mile serve? ▼
What type of violations does SCUA Upper Seven Mile have? ▼
Has PFAS been detected in SCUA Upper Seven Mile water? ▼
What water source does SCUA Upper Seven Mile use? ▼
Where does this data come from? ▼
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.