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Tap water quality report

S & T Mutual Water Company

EPA monitoring tested this supplier for 44 contaminants and detected 4. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

44
contaminants tested
4
detected
591
people served
0
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.

0
health-based violations
3
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Archived 1981-10-01 → 1982-09-30
MR Monitoring Archived 1980-10-30 → 1981-10-29
Other Monitoring Archived 1979-12-30 → 1980-01-29

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 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
18000 µg/L 180%
of the EPA limit, at the 95th percentile of samples — 10000 µg/L
 72/72 SYR4 2012–2019
Lead
0.0011 mg/L 7.3%
of the EPA limit 0.0150 mg/L
 4/4 LCR 2024
Nitrate-Nitrite
17400 µg/L 174%
of the EPA limit, at the 95th percentile of samples — 10000 µg/L
worst single sample: 18000 µg/L
3/3 SYR4 2017–2019
Copper
58 µg/L 4.5%
of the EPA limit 1300 µg/L
 1/5 SYR4 2013–2019
40 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-DichloropropaneAntimony, TotalArsenicAtrazineBariumBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbon TetrachlorideChromiumDichloromethaneDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateEthylbenzeneFluorideLassoLeadMercuryNitriteSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
REINEKE, BETH
Phone
503-410-1575
Email
[email protected]

Frequently asked questions about S & T Mutual Water Company

Is S & T Mutual Water Company tap water safe to drink?

EPA monitoring detected 4 contaminants in S & T Mutual 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 S & T Mutual Water Company's water?

EPA monitoring detected Nitrate, Lead, Nitrate-Nitrite, Copper. The full list with the level and data source for each is above.

How many people does S & T Mutual Water Company serve?

S & T Mutual Water Company reports serving 591 people in California, per its EPA record.

Has S & T Mutual Water Company had any water quality violations?

The EPA has 3 violations on file for S & T Mutual Water Company, of which 0 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.