Mapping California's Poisoned Wells

California state regulators have tested 600 wells across the state for toxic chemicals. The Los Angeles Times has created an interactive map which allow you to view the safety of the water in each well. Twenty-four of the wells now have a health advisory.

Hundreds of wells are contaminated across California. Find out where uses colored markers to highlight the wells where dangerous chemicals were detected, where no chemicals were detected and where a health advisory has been issued for the well. If you hover over a well on the map you can view the levels of PFOS and PFOA detected in the well (if any). The EPA has established health advisory levels at 70 parts per trillion for PFOS and PFOA.

PFOA and PFOS are chemicals which have been used in manufacturing since the 1940's. Both chemicals are very persistent both in the environment and in the human body. They are commonly known as 'forever chemicals'. This means that they don’t break down and their levels can therefore accumulate over time. Exposure to these chemicals can lead to adverse human health effects.



The Environmental Working Group has created a nationwide interactive map of PFC contamination in drinking water.The PFC Contamination Map uses data from the the Environmental Protection Agency to show the level of PFC's found in water supplies at the county level.

You can read more about the dangers of PFC's and the PFC Contamination Map in this EWG article. Many of the highest levels of PFC contamination in groundwater have been found at military sites (often from fire fighting foams containing PFC's). The EWG has also created a list of the 100 U.S. Military Sites With the Worst PFAS Contamination.