(MPUD) of the presence of Perfluorohexane Sulfonic Acid (PFHxS), which were indicated during testing to be above the response level of 20 nanograms as regulated by the State Water Resources Control Board. PFHxS was identified in two (2) wells used to service Mariposa Town and the neighborhoods towards John C. Fremont Hospital and the CalFire headquarters on Highway 49 North.
PFAS are manmade compounds which can derive from a wide variety of materials, which break down slowly over time, and are found in groundwaters and bottled waters across the world, at varying levels.
In most commercial industries, such as bottled water, there are no enforceable limits put in place by the Food and Drug Administration (FDA). Some private associations and the Environmental Protection Agency are working on standardized regulation of PFAS in groundwater and bottled water. There is not an identified timeline for the presence of PFAS or their impact on Mariposa ground water, however PFAS have been used in many industries since World War II.
MPUD has been given a timeline in which they must comply with the State Water Resources Control Boards PFAS regulations.
As a rural community, with a history of exposure to mining, construction, fire and other natural disasters, it is likely that water across the County will test positive for one of the currently identified PFAS.
Exposure to PFAS can cause health issues, and is not recommended for those who are pregnant, breastfeeding or using exposed water for formula.
Filter options which are known to reduce PFAS levels include reverse osmosis systems and activated carbon filters.
Bottled water companies should provide information regarding PFAS in their products.
At Mariposa County Health & Human Services we are taking steps to work with our partners at MPUD and local businesses across the county to ensure information is made available.
Our priority is ensuring that each individual has the opportunity to make educated decisions for their health.
For resources regarding well testing in Mariposa, please contact Environmental Health at 1-209-966-2220, for information regarding the EPA understanding of PFAS and resources visit https://www.epa.gov/pfas.
Source: Mariposa County Public Health
