# Llano Mutual Water Company — Llano, Ca, CA — Drinking Water Quality (2021)

> Contaminant levels for the Llano Mutual Water Company — Llano, Ca, CA public water system from its 2021 Consumer Confidence Report, compared to federal limits.

- Page: https://www.thewatermap.com/water/ca/llano-mutual-water-company-llano-ca/2021
- JSON API: https://www.thewatermap.com/api/water/ca/llano-mutual-water-company-llano-ca/2021
- Source: the utility's annual Consumer Confidence Report (CCR)
- Verification: transcribed by a model, cross-checked by a second model, approved before publishing
- Reporting year: 2021
- Contaminants measured: 18
- Contaminants with a federal limit: 6
- Contaminants at or above the federal limit: 1
- Part of The Water Map — https://www.thewatermap.com

## Contaminants measured

| Contaminant | Category | Measured level | Sampling context | Federal limit | Status |
|---|---|---|---|---|---|
| Perchlorate | Disinfection byproducts | Not detected (Reported level) | System-wide | No federal limit | None detected |
| Asbestos | Inorganic chemicals | Not detected (Reported level) | System-wide | No federal limit | None detected |
| Fluoride | Inorganic chemicals | 0.35–0.37 (Range) | System-wide | 2 (MCL) | Detected — no federal limit |
| Nitrate | Inorganic chemicals | 0.53–0.64 (Range) | System-wide | 10 (MCL) | Detected — no federal limit |
| Sulfate | Inorganic chemicals | 80–87 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Calcium | Metals | 75–82 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Copper | Metals | 0.16 mg/L (90th percentile) | At the tap | 1.3 mg/L (Action level) | Within the limit |
| Lead | Metals | Not detected ug/L (90th percentile) | At the tap | No federal limit | Within the limit |
| Magnesium | Metals | 22–24 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Potassium | Metals | 5–5.5 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Escherichia coli (E. coli) | Microbial | 0 (Highest single sample) | No. of Detections | 0 (MCLG) | None detected |
| Total Coliform | Microbial | 2 (Highest single sample) | No. of Detections | No federal limit | Detected — no federal limit |
| Nitrate Nitrite | Other | Not detected (Reported level) | System-wide | 10 (MCL) | None detected |
| Alkalinity | Physical & aggregate | 250 (Reported level) | System-wide | No federal limit | Detected — no federal limit |
| Bicarbonate | Physical & aggregate | 300 (Reported level) | System-wide | No federal limit | Detected — no federal limit |
| pH | Physical & aggregate | 7.7–7.9 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Turbidity | Physical & aggregate | 1 NTU (Reported level) | System-wide | No federal limit | At or above the limit |
| Uranium | Radionuclides | 2.6–2.9 (Range) | System-wide | 20 (MCL) | Detected — no federal limit |

## What these contaminants are

- **Perchlorate** — A chemical used in rocket fuel and fireworks that can also form during disinfection. Can interfere with thyroid hormone production; has no national enforceable limit but is regulated in some states.
- **Fluoride** — A mineral often added to drinking water to help prevent tooth decay. Beneficial at low levels, but long-term exposure above the federal limit can cause bone disease and tooth mottling.
- **Nitrate** — A compound from fertilizer runoff, septic systems, and erosion of natural deposits. Levels above the federal limit can cause 'blue baby syndrome,' a serious oxygen-transport condition in infants.
- **Sulfate** — A naturally occurring mineral from rock and soil. No health-based federal limit; high levels can have a laxative effect and a bitter taste.
- **Calcium** — A naturally occurring mineral that contributes to water hardness. Not federally regulated for health; affects scaling and taste.
- **Copper** — A metal that enters water from corroding household plumbing. Short-term exposure causes stomach distress; long-term exposure can damage the liver and kidneys.
- **Lead** — A toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. There is no safe level of lead; it harms brain development in children and raises blood pressure in adults. The EPA sets an action level, not a health goal above zero.
- **Magnesium** — A naturally occurring mineral that contributes to water hardness. Not federally regulated for health; affects scaling and taste.
- **Potassium** — A naturally occurring mineral from rock and soil. Not federally regulated for health.
- **Escherichia coli (E. coli)** — Escherichia coli — bacteria found in the gut of humans and animals. Its presence in drinking water indicates fecal contamination and a real risk of waterborne illness.
- **Total Coliform** — A group of bacteria used as an indicator of overall water-system sanitation. Coliforms themselves are usually harmless, but their presence signals that disease-causing organisms could enter the system.
- **Alkalinity** — A measure of the water's capacity to neutralize acids. Not federally regulated for health; relevant to corrosion control and treatment.
- **pH** — A measure of how acidic or basic the water is. Regulated only as a secondary standard; very low or high pH can corrode pipes or affect taste.
- **Turbidity** — A measure of cloudiness from suspended particles in the water. High turbidity can shelter microbes from disinfection; the EPA enforces it through a treatment-technique standard.
- **Uranium** — A naturally occurring radioactive metal from erosion of natural deposits. Long-term exposure above the federal limit can damage the kidneys and increase cancer risk.

## How to read this

- A water-quality report covers an entire service area, not a single address.
- 'Federal limit' is the EPA standard (MCL, action level, treatment technique, etc.) that the measured level is compared against.
- 'At or above the federal limit' means the utility's own reported figure met or exceeded that standard.

_Figures are the utility's own published numbers. Generated 2026-06-04 from thewatermap.com._