In early 2004 you may have noticed water well drilling taking place within CarmichaelmonitoringWell Water District’s service area, especially near Grant Avenue, Hollister Avenue and Marshall Avenue. The purpose of the water well drilling is to monitor for potential contaminants, such as N-nitrosodimethylamine (NDMA).

During the last quarter of 2003, Aerojet drilled a test well located in Rancho Cordova at Rossmoor Bar. Rossmoor Bar is located in the American River Parkway directly across the river from the end of Landis Avenue. Samples from the test well detected the presence of NDMA in the range of 200-300 mg/L (milligrams per liter or parts per million). Because of these high levels, Aerojet has been ordered to drill additional monitoring wells within the Carmichael Water District’s service area. The purpose of these monitoring wells is to determine if NDMA or any other contaminant has crossed under the American River into Carmichael.

NDMA is a contaminant of recent concern by drinking water regulators because of its discovery in contaminated groundwater supplies. NDMA is identified as a carcinogen by Title 22, California Code of Regulations (22CCR), Section 12000 pursuant to the Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65), Health and Safety Code Section 25249.5, et, . In April 1998, California Department of Health Services (DHS) established a drinking water action level (AL) for NDMA of 2 ng/L (nano grams per liter or parts per trillion).

The United States Environmental Protection Agency (EPA) also evaluated the health effects of NDMA and classifies it as a probable human carcinogen. Following the initial northern California findings in February 1998, DHS informed affected Drinking Water Utilities that the Office of Environmental Health Hazard Assessment (OEHHA) had evaluated NDMA’s cancer risk. OEHHA established in 22CCR 12705(b)(1) a 0.04 ug/l per day exposure level for NDMA for “no significant risk”, for purposes of Proposition 65’s warning requirements and discharge prohibition. This equates to 0.02 ug/L (parts per billion) in drinking water, using a 2-liter daily consumption for 70 years. This corresponds to a theoretical risk of up to one excess case of cancer per million people drinking 2 liters of water per day for a 70-year lifetime.

Since 2000, Carmichael Water District has tested all ground water wells and surface water supply for NDMA and to date has had zero detections. In 2001, Carmichael Water District completed it new Surface Water Treatment. The new plant has the capacity to deliver up to 90% of the District’s water supply needs. The District will continue to monitor the results from Aerojet’s monitoring and to conduct its own testing for NDMA in all its drinking water supplies.


Update – January 16, 2017   

On January 16, 2017 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well on Grant Avenue immediately west of Hollister Avenue.  This work is being conducted by Aerojet Rocketdyne and is scheduled to begin no earlier than January 31, 2017.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – November 10, 2016   

On November 10, 2016 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well near Marshall Avenue immediately north of Sutter Avenue.  This work is being conducted by Aerojet Rocketdyne and is scheduled to begin no earlier than November 28, 2016.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – March 24, 2016   

On March 24, 2016 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well near Oak Cliff Circle immediately south of Stanley Avenue.  This work is being conducted by Aerojet Rocketdyne and is scheduled to begin no earlier than March 15, 2016.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – March 4, 2016  

On March 4, 2016 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well near the intersection of Landis Avenue and Lindi Court.  This work is being conducted by Aerojet Rocketdyne and is scheduled to begin no earlier than March 15, 2016.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – February 19, 2016 

On February 19, 2016 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well on the western portion of Waynart Court.  This work is being conducted by Aerojet Rocketdyne and is scheduled to begin no earlier than February 22, 2016.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – June 11, 2015

On June 11, 2015 Carmichael Water District received a notice that Aerojet Rocketdyne will be adding an additional monitoring well on the east side of Marshall Avenue north of Grant Avenue.  This work is being conducted by Aerojet Rocketdyne and will begin in June of 2015.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.

Update – May 21, 2014

On May 19, 2014 Carmichael Water District received a notice that Aerojet will be adding an additional monitoring well on the east side of Queenston Court cul-de-sac.  This work is being conducted by Aerojet and will begin in June of 2014.  For information regarding this project, please contact Cindy Caulk, of Aerojet Rocketdyne Environmental Health and safety Communications at (916) 355-2601.