Non-Transient Non-Community Water System · PWS CA0900111
Pioneer Elementary School
Operator location Somerset, California - smaller served population (≤ 999) at 227 people served; 51 SDWIS violations on record from groundwater sources.
- 227
- People served (this PWS) Smaller third of systems
- 51
- EPA violations (this PWS) Middle third of systems
- 4
- Health-based (this PWS) Middle third by health-based share
- Untested
- UCMR5 (this PWS) No UCMR5 result
Pioneer Elementary School standing, mid SDWIS violation third
227 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 8% is middle-third health share (≤ 23%).
The verdict
Pioneer Elementary School lands in the middle third by violation volume (51), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (227; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 8% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 51
- Total EPA violations on record
- 8%
- Health-based (MCL / treatment failure)
- 227
- People served by this PWS (SDWIS)
- N/A
- PFAS compounds detected (UCMR5)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
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 |
Violation Count vs. the National Corpus
Pioneer Elementary School has 51 recorded EPA violations, 57% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 43% carry more. 8% of this system's own violations are health-based (4 of 51), and it ranks unranked by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
51 Around the middle fewer violations than 43% 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
How many violations vs. how serious, among peer systems
Pioneer Elementary School plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
Population served record for Pioneer Elementary School
EPA SDWIS lists 227 people served and 19 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
51 violations · 227 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
What to do with Pioneer Elementary School
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in California compares on the same EPA violation measures. California 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.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.