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Tap water quality report

Rim Rock Water Company

EPA monitoring tested this supplier for 41 contaminants and detected 7. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

41
contaminants tested
7
detected
55
people served
62
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Private
Counties served
San Luis Obispo

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

62
health-based violations
69
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2025-04-01 → 2025-06-30
MCL Health-based Resolved 2025-04-01 → 2025-06-30
MCL Health-based Resolved 2025-01-01 → 2025-03-31
MCL Health-based Resolved 2025-01-01 → 2025-03-31
MCL Health-based Resolved 2024-10-01 → 2024-12-31
MCL Health-based Resolved 2024-10-01 → 2024-12-31
MCL Health-based Resolved 2024-07-01 → 2024-09-30
MCL Health-based Resolved 2024-07-01 → 2024-09-30
MCL Health-based Resolved 2024-04-01 → 2024-06-30
MCL Health-based Resolved 2024-04-01 → 2024-06-30

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Arsenic
120 µg/L 1200%
of the EPA limit, in the worst sample — 10 µg/L
 20/23 SYR4 2013–2019
Fluoride
490 µg/L 12%
of the EPA limit 4000 µg/L
 3/3 SYR4 2013–2017
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 3/3 LCR 2024
Barium
24.2 µg/L 1.2%
of the EPA limit 2000 µg/L
 1/3 SYR4 2013–2017
Copper
220 µg/L 17%
of the EPA limit 1300 µg/L
 1/3 SYR4 2013–2017
Chromium
2 µg/L 2%
of the EPA limit 100 µg/L
 1/3 SYR4 2013–2017
Selenium
4 µg/L 8%
of the EPA limit 50 µg/L
 1/3 SYR4 2013–2017
34 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-DichloropropaneAntimony, TotalAtrazineBenzeneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbon TetrachlorideDichloromethaneEthylbenzeneLassoLeadMercuryNitrateNitrate-NitriteNitriteSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
ELDER, ERIC
Phone
805-441-1391
Email
ericeelder@aol.com

Frequently asked questions about Rim Rock Water Company

Is Rim Rock Water Company tap water safe to drink?

EPA monitoring detected 7 contaminants in Rim Rock Water Company's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Rim Rock Water Company's water?

EPA monitoring detected Arsenic, Fluoride, Lead, Barium, Copper, and others. The full list with the level and data source for each is above.

How many people does Rim Rock Water Company serve?

Rim Rock Water Company reports serving 55 people in California, per its EPA record.

Has Rim Rock Water Company had any water quality violations?

The EPA has 69 violations on file for Rim Rock Water Company, of which 62 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.