MTBE
Chaffee PWS
MTBE was used as gasoline oxygenation additive to boost the octane number. In 2005, MTBE was replaced by ethanol as a gasoline additive. MTBE causes cancers in rats.
23
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 | 1.57 ppb | 4 | 3 | ND - 2.74 ppb |
| 2019 | 1.51 ppb | 4 | 2 | ND - 3.44 ppb |
| 2020 | ND | 3 | 0 | ND |
| 2021 | 1.16 ppb | 4 | 2 | ND - 2.41 ppb |
| 2022 | 1.58 ppb | 4 | 3 | ND - 2.34 ppb |
| 2023 | 1.04 ppb | 4 | 2 | ND - 2.27 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 13 ppb
The EWG Health Guideline of 13 ppb for MTBE was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-10 | AD12050 | 1.29 ppb |
| 2018-05-06 | AD18663 | ND |
| 2018-07-16 | AD29540 | 2.74 ppb |
| 2018-10-15 | AD35060 | 2.26 ppb |
| 2019-01-09 | AD38372 | 2.60 ppb |
| 2019-04-08 | AD46663 | ND |
| 2019-07-10 | AD52709 | 3.44 ppb |
| 2019-10-20 | AD57371 | ND |
| 2020-01-13 | AD60690 | ND |
| 2020-07-15 | 2011704 | ND |
| 2020-10-18 | 2016623 | ND |
| 2021-01-11 | 2020222 | 2.24 ppb |
| 2021-04-12 | 2103835 | ND |
| 2021-07-12 | 2113757 | ND |
| 2021-10-19 | 2118151 | 2.41 ppb |
| 2022-01-05 | 2121647 | 2.14 ppb |
| 2022-04-13 | 2204388 | 2.34 ppb |
| 2022-07-11 | 2214803 | 1.82 ppb |
| 2022-10-09 | 2219685 | ND |
| 2023-01-09 | 2223354 | 1.88 ppb |
| 2023-04-12 | 2303495 | 2.27 ppb |
| 2023-07-16 | 2311711 | ND |
| 2023-10-18 | 2316866 | ND |