Chromium (total)
Foothill Estates Ws
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 | ND | 1 | 0 | ND |
| 2019 | N/A | 0 | 0 | N/A |
| 2020 | ND | 2 | 0 | ND |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | 4.20 ppb | 4 | 4 | 3.30 ppb - 5.10 ppb |
| 2023 | 2.67 ppb | 6 | 4 | ND - 5.30 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 |
|---|---|---|
| 2018-12-18 | CA2702198_002_002-201812181601 | ND |
| 2020-08-27 | CA2702198_002_002-202008271331 | ND |
| 2020-11-19 | CA2702198_002_002-202011191436 | ND |
| 2022-06-24 | CA2702198_002_002-202206241104 | 5.10 ppb |
| 2022-09-26 | CA2702198_002_002-202209261142 | 3.70 ppb |
| 2022-11-30 | CA2702198_002_002-202211300944 | 3.30 ppb |
| 2022-12-14 | CA2702198_002_002-202212141434 | 4.70 ppb |
| 2023-03-28 | CA2702198_002_002-202303281530 | 3.00 ppb |
| 2023-06-23 | CA2702198_002_002-202306231305 | 3.50 ppb |
| 2023-08-24 | CA2702198_002_002-202308241439 | ND |
| 2023-09-19 | CA2702198_001_001-202309191413 | ND |
| 2023-10-06 | CA2702198_001_001-202310060930 | 5.30 ppb |
| 2023-11-28 | CA2702198_002_002-202311280930 | 4.20 ppb |