Nitrate and nitrite
Bull Run Mountain/evergreen (brme)
Nitrate and nitrite enter water from fertilizer runoff, septic tanks and urban runoff. These contaminants can cause oxygen deprivation for infants and increase the risk of cancer. Nitrite is significantly more toxic than nitrate. Click here to read more about nitrate.
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 | 0.153 ppm | 6 | 2 | ND - 0.480 ppm |
| 2019 | 0.220 ppm | 6 | 2 | ND - 0.770 ppm |
| 2020 | 0.250 ppm | 6 | 2 | ND - 0.970 ppm |
| 2021 | 0.248 ppm | 6 | 2 | ND - 0.950 ppm |
| 2022 | 0.267 ppm | 6 | 3 | ND - 0.560 ppm |
| 2023 | 0.203 ppm | 6 | 2 | ND - 0.680 ppm |
ppm = parts per million
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.14 ppm
The EWG health guideline of 0.14 parts per million, or ppm, for nitrate and nitrite is based on the equivalent health guideline for nitrate, as defined in a peer-reviewed scientific study by EWG. This guideline represents a one-in-one-million annual cancer risk level.
EPA Maximum Contaminant
Level (MCL): 10 ppm
ppm = parts per million
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-07-18 | WE-1-1807N | ND |
| 2018-07-18 | WB-7-1807N | 0.480 ppm |
| 2018-07-18 | WB-5-1807N | ND |
| 2018-07-18 | WB-13-1807N | ND |
| 2018-07-18 | WB-11-1807N | 0.440 ppm |
| 2018-07-18 | WB-12-1807N | ND |
| 2019-10-28 | WB-12-1910N | ND |
| 2019-10-28 | WB-11-1910N | 0.550 ppm |
| 2019-10-28 | WE-1-1910N | ND |
| 2019-10-28 | WB-7-1910N | 0.770 ppm |
| 2019-10-28 | WB-5-1910N | ND |
| 2019-10-28 | WB-13-1910N | ND |
| 2020-02-24 | WE-1-2002N | ND |
| 2020-02-24 | WB-7-2002N | 0.970 ppm |
| 2020-02-24 | WB-5-2002N | ND |
| 2020-02-24 | WB-13-2002N | ND |
| 2020-02-24 | WB-12-2002N | ND |
| 2020-02-24 | WB-11-2002N | 0.530 ppm |
| 2021-04-27 | 21042610-01NO2NO3 | ND |
| 2021-04-27 | 21042610-06NO2NO3 | ND |
| 2021-04-27 | 21042610-05NO2NO3 | ND |
| 2021-04-27 | 21042610-04NO2NO3 | ND |
| 2021-04-27 | 21042610-03NO2NO3 | 0.540 ppm |
| 2021-04-27 | 21042610-02NO2NO3 | 0.950 ppm |
| 2022-07-26 | 22072601-06NO2NO3 | ND |
| 2022-07-26 | 22072601-03NO2NO3 | 0.550 ppm |
| 2022-07-26 | 22072601-02NO2NO3 | 0.560 ppm |
| 2022-07-26 | 22072601-01NO2NO3 | ND |
| 2022-09-29 | 22092907-01_NO2NO3 | ND |
| 2022-12-13 | 22121301-02_NO2NO3 | 0.490 ppm |
| 2023-10-24 | 23102311-01_NO2NO3 | ND |
| 2023-10-24 | 23102311-02_NO2NO3 | 0.680 ppm |
| 2023-10-24 | 23102311-03_NO2NO3 | 0.540 ppm |
| 2023-10-24 | 23102311-04_NO2NO3 | ND |
| 2023-10-24 | 23102311-05_NO2NO3 | ND |
| 2023-10-24 | 23102311-06_NO2NO3 | ND |