Chromium (total)
Cazadero Water Company Inc.
Chromium is a naturally occurring metal, but industrial uses can elevate its levels in water. One form, hexavalent chromium, causes cancer. Total chromium is not a good indicator of the amount of hexavalent chromium in drinking water.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | N/A | 0 | 0 | N/A |
| 2019 | ND | 2 | 0 | ND |
| 2020 | ND | 1 | 0 | ND |
| 2021 | ND | 3 | 0 | ND |
| 2022 | ND | 2 | 0 | ND |
| 2023 | ND | 2 | 0 | ND |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EPA Maximum Contaminant
Level (MCL): 100 ppb
The legal limit for total chromium, established in 1991, was based on a 1958 toxicity study in laboratory animals, and applies to both the less-toxic trivalent chromium and the more-toxic hexavalent chromium forms of this compound. This limit does not protect against the risk of cancer from ingestion of hexavalent chromium.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2019-03-22 | CA4900508_011_011-201903221030 | ND |
| 2019-03-22 | CA4900508_005_005-201903221010 | ND |
| 2020-12-21 | CA4900508_011_011-202012210725 | ND |
| 2021-04-01 | CA4900508_001_001-202104010917 | ND |
| 2021-04-01 | CA4900508_006_006-202104010933 | ND |
| 2021-06-08 | CA4900508_005_005-202106080926 | ND |
| 2022-03-14 | CA4900508_011_011-202203141039 | ND |
| 2022-11-03 | CA4900508_005_005-202211031155 | ND |
| 2023-03-06 | CA4900508_011_011-202303060912 | ND |
| 2023-12-11 | CA4900508_005_005-202312111300 | ND |