Chromium (total)
City of Hollister
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.
10
Samples
0
Samples exceeding legal limit (MCL)
0
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 | N/A | 0 | 0 | N/A |
| 2020 | 5.40 ppb | 5 | 2 | ND - 14.0 ppb |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | N/A | 0 | 0 | N/A |
| 2023 | 8.20 ppb | 5 | 3 | ND - 15.0 ppb |
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 |
|---|---|---|
| 2020-05-14 | CA3510001_001_001-202005140935 | ND |
| 2020-05-14 | CA3510001_002_002-202005140930 | ND |
| 2020-05-14 | CA3510001_005_005-202005140840 | 13.0 ppb |
| 2020-05-14 | CA3510001_007_007-202005140830 | ND |
| 2020-06-03 | CA3510001_006_006-202006031154 | 14.0 ppb |
| 2023-02-15 | CA3510001_005_005-202302151010 | 13.0 ppb |
| 2023-02-15 | CA3510001_006_006-202302151045 | 13.0 ppb |
| 2023-02-15 | CA3510001_007_007-202302151100 | 15.0 ppb |
| 2023-02-15 | CA3510001_001_001-202302150855 | ND |
| 2023-02-15 | CA3510001_002_002-202302150925 | ND |