Chromium (total)
The Mountain Water System
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 | N/A | 0 | 0 | N/A |
| 2021 | N/A | 0 | 0 | N/A |
| 2022 | 0.950 ppb | 2 | 1 | ND - 1.90 ppb |
| 2023 | 0.500 ppb | 2 | 1 | ND - 1.000 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 |
|---|---|---|
| 2019-02-26 | 301433-2019-DWI | ND |
| 2019-02-26 | 301435-2019-DW | ND |
| 2022-03-14 | FWC0175-01A | 1.90 ppb |
| 2022-05-23 | FWE0087 | ND |
| 2023-04-05 | FXC0474-01 | 1.000 ppb |
| 2023-04-05 | FXC0634-01 | ND |