Know Your Environment. Protect Your Health.

Arsenic

Pg&e Helms Support Facility

Arsenic is a potent carcinogen and common contaminant in drinking water. Arsenic causes thousands of cases of cancer each year in the U.S. Click here to read more about arsenic.

 

100

Samples

51

Samples exceeding legal limit (MCL)

61

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
201816.4 ppb147ND - 42.0 ppb
201919.1 ppb126ND - 40.0 ppb
202014.3 ppb83ND - 38.0 ppb
202121.1 ppb1810ND - 45.0 ppb
202219.5 ppb2217ND - 44.0 ppb
202320.5 ppb2618ND - 45.0 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.004 ppb

The EWG Health Guideline of 0.004 ppb for arsenic 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.

EPA Maximum Contaminant
Level (MCL): 10 ppb

The legal limit for arsenic, established in 2001, was based on costs for arsenic removal, as calculated at the time that the standard was set. This limit does not fully protect against the risk of cancer due to arsenic exposure.

ppb = parts per billion

All test results

Date Lab ID Result
2018-01-12CA1000472_001_001-20180112123036.0 ppb
2018-02-23CA1000472_002_002-201802231330ND
2018-03-08CA1000472_002_002-201803081320ND
2018-03-08CA1000472_001_001-20180308130036.0 ppb
2018-04-06CA1000472_002_002-201804061315ND
2018-05-11CA1000472_001_001-20180511124538.0 ppb
2018-05-11CA1000472_002_002-201805111300ND
2018-06-08CA1000472_002_002-201806081245ND
2018-07-10CA1000472_002_002-201807101330ND
2018-07-12CA1000472_001_001-20180712130037.0 ppb
2018-09-12CA1000472_002_002-20180912133042.0 ppb
2018-10-02CA1000472_002_002-2018100213302.60 ppb
2018-11-07CA1000472_001_001-20181107130038.0 ppb
2018-11-07CA1000472_002_002-201811071330ND
2019-03-07CA1000472_002_002-201903071230ND
2019-03-14CA1000472_001_001-20190314123036.0 ppb
2019-04-02CA1000472_002_002-201904021230ND
2019-06-04CA1000472_001_001-20190604125040.0 ppb
2019-06-04CA1000472_002_002-201906041300ND
2019-06-20CA1000472_001_001-20190620133037.0 ppb
2019-06-20CA1000472_001_001-20190620133039.0 ppb
2019-08-20CA1000472_002_002-201908201335ND
2019-09-26CA1000472_001_001-20190926125040.0 ppb
2019-09-26CA1000472_001_001-20190926125037.0 ppb
2019-11-12CA1000472_002_002-201911121130ND
2019-12-12CA1000472_002_002-201912121320ND
2020-02-18CA1000472_002_002-202002181240ND
2020-02-18CA1000472_001_001-20200218123038.0 ppb
2020-07-06CA1000472_001_001-20200706124038.0 ppb
2020-07-06CA1000472_002_002-202007061235ND
2020-09-21CA1000472_001_001-20200921111038.0 ppb
2020-09-21CA1000472_002_002-202009211105ND
2020-10-05CA1000472_002_002-202010051145ND
2020-11-02CA1000472_002_002-202011021130ND
2021-01-04CA1000472_001_001-20210104105036.0 ppb
2021-01-04CA1000472_002_002-202101041040ND
2021-01-04CA1000472_002_002-202101041040ND
2021-01-04CA1000472_001_001-20210104105036.0 ppb
2021-02-01CA1000472_002_002-202102011245ND
2021-02-01CA1000472_001_001-20210201121540.0 ppb
2021-02-01CA1000472_002_002-202102011245ND
2021-02-01CA1000472_001_001-20210201121540.0 ppb
2021-03-01CA1000472_001_001-20210301123038.0 ppb
2021-03-01CA1000472_002_002-202103011215ND
2021-04-01CA1000472_001_001-20210401120040.0 ppb
2021-04-01CA1000472_002_002-202104011235ND
2021-05-03CA1000472_002_002-202105031000ND
2021-05-03CA1000472_001_001-20210503090045.0 ppb
2021-07-06CA1000472_001_001-20210706120040.0 ppb
2021-11-11CA1000472_002_002-202111111030ND
2021-12-07CA1000472_002_002-20211207110023.0 ppb
2021-12-07CA1000472_001_001-20211207103042.0 ppb
2022-01-04CA1000472_001_001-20220104133038.0 ppb
2022-01-04CA1000472_002_002-202201041315ND
2022-03-07CA1000472_001_001-20220307123040.0 ppb
2022-03-07CA1000472_002_002-2022030712152.30 ppb
2022-04-04CA1000472_001_001-20220404110039.0 ppb
2022-04-04CA1000472_002_002-202204041130ND
2022-05-02CA1000472_001_001-20220502133041.0 ppb
2022-05-02CA1000472_002_002-202205021300ND
2022-06-07CA1000472_002_002-202206071215ND
2022-06-07CA1000472_001_001-20220607114544.0 ppb
2022-07-05CA1000472_001_001-20220705100512.0 ppb
2022-07-05CA1000472_002_002-202207051030ND
2022-08-01CA1000472_002_002-2022080113051.70 ppb
2022-08-01CA1000472_001_001-20220801123041.0 ppb
2022-09-06CA1000472_001_001-20220906110027.0 ppb
2022-09-06CA1000472_002_002-2022090611451.20 ppb
2022-10-03CA1000472_002_002-2022100313002.50 ppb
2022-10-03CA1000472_001_001-20221003123041.0 ppb
2022-11-14CA1000472_002_002-20221114103015.0 ppb
2022-11-14CA1000472_001_001-20221114100040.0 ppb
2022-12-06CA1000472_002_002-2022120612301.40 ppb
2022-12-06CA1000472_001_001-20221206120042.0 ppb
2023-02-07CA1000472_001_001-20230207104541.0 ppb
2023-02-07CA1000472_002_002-2023020711152.30 ppb
2023-03-20CA1000472_001_001-20230320100541.0 ppb
2023-03-20CA1000472_002_002-2023032010302.60 ppb
2023-04-17CA1000472_001_001-20230417130041.0 ppb
2023-04-17CA1000472_002_002-2023041713451.40 ppb
2023-05-15CA1000472_001_001-20230515133045.0 ppb
2023-05-26CA1000472_001_001-20230526104539.0 ppb
2023-05-26CA1000472_002_002-2023052611306.30 ppb
2023-07-03CA1000472_001_001-20230703123044.0 ppb
2023-07-31CA1000472_002_002-202307311300ND
2023-08-17CA1000472_002_002-202308170900ND
2023-08-17CA1000472_001_001-20230817084541.0 ppb
2023-08-17CA1000472_DST_901-20230817100012.0 ppb
2023-08-25CA1000472_001_001-20230825110039.0 ppb
2023-08-25CA1000472_DST_901-20230825120021.0 ppb
2023-08-25CA1000472_002_002-202308251130ND
2023-10-03CA1000472_001_001-20231003124541.0 ppb
2023-10-03CA1000472_002_002-202310031315ND
2023-10-05CA1000472_002_002-202310051330ND
2023-10-05CA1000472_DST_901-202310051345ND
2023-11-01CA1000472_001_001-20231101123036.0 ppb
2023-11-06CA1000472_002_002-202311061115ND
2023-11-06CA1000472_001_001-20231106103039.0 ppb
2023-12-05CA1000472_002_002-202312051015ND
2023-12-05CA1000472_001_001-20231205103041.0 ppb