Non-Transient Non-Community Water System · PWS CA0900111
Pioneer Elementary School
Somerset, California 95684 - drinking water served from groundwater sources to 227 people, tracked in EPA SDWIS and UCMR5.
- 227
- People served
- 51
- EPA violations
- 4
- Health-based
- Untested
- UCMR5 result
The verdict
EPA records 51 drinking-water violations at Pioneer Elementary School, 8% of them health-based - above the California per-system average.
- 51
- Total EPA violations on record
- 8%
- Health-based (MCL / treatment failure)
- 227
- People served by this system
- N/A
- PFAS compounds detected (UCMR5)
Water Quality Snapshot: Pioneer Elementary School
Pioneer Elementary School is a local-owned non-transient non-community water system that delivers drinking water to 227 residents in Somerset, California (El Dorado County) through 19 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 51 total violations for this system , of which 4 (8%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 42 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.
The most frequently cited contaminant at this system is Lead and Copper Rule, recorded in 8 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.
Across California, EPA tracks 7,249 public water systems serving 42,404,883 people, with 153,308 cumulative violations and 63,983 health-based violations on record. About 89% of systems in the state carry at least one violation, and state-wide the average per system is 21.1 violations. Statewide, 447 of 694 UCMR5-tested systems have reported PFAS detections (64.4%).
Pioneer Elementary School's 51 violations sit above the California average.
All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.
System Details
- System Type
- Non-Transient Non-Community
- Owner Type
- Local
- Connections
- 19
- County
- El Dorado
- School/Daycare
- Yes
- MCL Violations
- 3
- Monitoring Violations
- 42
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Lead and Copper Rule | MR | 8 | 2024 |
| Coliform (TCR) | MCL | 3 | 2008 |
| Revised Total Coliform Rule | MON | 2 | 2022 |
| Nitrate-Nitrite | MR | 2 | 2021 |
| Consumer Confidence Rule | Other | 2 | 2022 |
| Diquat | MR | 1 | 2019 |
| Benzo(a)pyrene | MR | 1 | 2019 |
| Carbofuran | MR | 1 | 2019 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2019 |
| Atrazine | MR | 1 | 2019 |
| 2,4,5-TP | MR | 1 | 2019 |
| Methoxychlor | MR | 1 | 2019 |
| Glyphosate | MR | 1 | 2019 |
| Simazine | MR | 1 | 2019 |
| OXAMYL | MR | 1 | 2019 |
| Toxaphene | MR | 1 | 2019 |
| HEXACHLOROBENZENE | MR | 1 | 2019 |
| LASSO | MR | 1 | 2019 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2019 |
| BHC-GAMMA | MR | 1 | 2019 |
| Chlordane | MR | 1 | 2019 |
| Picloram | MR | 1 | 2019 |
| Total Polychlorinated Biphenyls (PCB) | MR | 1 | 2019 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
| Heptachlor epoxide | MR | 1 | 2019 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 2019 |
| Heptachlor | MR | 1 | 2019 |
| LEAD AND COPPER RULE REVISIONS | RPT | 1 | 2024 |
| Endothall | MR | 1 | 2019 |
| Endrin | MR | 1 | 2019 |
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 Pioneer Elementary School.
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 CA0900111 on SDWISSource: EPA SDWIS Federal Reports Search
California Drinking Water Authority
California State Water Resources Control Board, Division of Drinking Water is the primacy agency that licenses and inspects Pioneer Elementary School under EPA-delegated authority.
Open CA regulator portalSource: California State Water Resources Control Board, Division of Drinking Water
Violation 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 |
|---|---|---|---|---|
| 2024 | Lead and Copper Rule | MR | 8 | SDWIS / CA0900111 / 5000 |
| 2024 | LEAD AND COPPER RULE REVISIONS | TT | 1 | SDWIS / CA0900111 / 5200 |
| 2024 | LEAD AND COPPER RULE REVISIONS | RPT | 1 | SDWIS / CA0900111 / 5200 |
| 2022 | Revised Total Coliform Rule | MON | 2 | SDWIS / CA0900111 / 8000 |
| 2022 | Consumer Confidence Rule | Other | 2 | SDWIS / CA0900111 / 7000 |
| 2021 | Nitrate-Nitrite | MR | 2 | SDWIS / CA0900111 / 1038 |
| 2019 | Diquat | MR | 1 | SDWIS / CA0900111 / 2032 |
| 2019 | Benzo(a)pyrene | MR | 1 | SDWIS / CA0900111 / 2306 |
| 2019 | Carbofuran | MR | 1 | SDWIS / CA0900111 / 2046 |
| 2019 | Di(2-ethylhexyl) phthalate | MR | 1 | SDWIS / CA0900111 / 2039 |
| 2019 | Atrazine | MR | 1 | SDWIS / CA0900111 / 2050 |
| 2019 | 2,4,5-TP | MR | 1 | SDWIS / CA0900111 / 2110 |
| 2019 | Methoxychlor | MR | 1 | SDWIS / CA0900111 / 2015 |
| 2019 | Glyphosate | MR | 1 | SDWIS / CA0900111 / 2034 |
| 2019 | Simazine | MR | 1 | SDWIS / CA0900111 / 2037 |
How Pioneer Elementary School Compares
Cross-reference this system's record against state averages and the federal MCL framework for context.
| Metric | Pioneer Elementary School | California avg | Federal benchmark |
|---|---|---|---|
| Total violations | 51 | 21.1 | SDWA compliance, any non-zero count is a recorded breach |
| Health-based violations | 4 | 8.8 | Indicates a contaminant exceeded a federal MCL |
| PFAS detection | None | 64.4% | EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt |
| Population served | 227 | 5,850 | Sizing context for compliance burden |
Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 7,249 regulated public water systems in California.
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 Pioneer Elementary School water safe to drink? ▼
How many people does Pioneer Elementary School serve? ▼
What type of violations does Pioneer Elementary School have? ▼
Has PFAS been detected in Pioneer Elementary School water? ▼
What water source does Pioneer Elementary School 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.