Chromium (total)
Dierks Water Works
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 | ND | 1 | 0 | ND |
| 2020 | 0.500 ppb | 4 | 1 | ND - 2.00 ppb |
| 2021 | 0.375 ppb | 4 | 1 | ND - 1.50 ppb |
| 2022 | ND | 1 | 0 | ND |
| 2023 | 2.00 ppb | 1 | 1 | 2.00 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 |
|---|---|---|
| 2018-02-13 | Y180460002 | ND |
| 2019-01-15 | Y190170016 | ND |
| 2020-01-29 | Y200300001 | 2.00 ppb |
| 2020-09-02 | Y202470023 | ND |
| 2020-09-14 | Y202610053 | ND |
| 2020-11-04 | Y203100053 | ND |
| 2021-01-26 | Y210280007 | ND |
| 2021-04-14 | Y211050044 | ND |
| 2021-08-03 | Y212170040 | 1.50 ppb |
| 2021-10-19 | Y212940026 | ND |
| 2022-01-11 | Y220130003 | ND |
| 2023-01-11 | Y230110009 | 2.00 ppb |