19E - WATER QUALITY REPORT - Laserfiche WebLink

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Receive and File Report on Water Quality May 21, 2019 Page 2 chemicals. Wells in the Santa Ana River recharge area have tested positive for these two chemicals. PFAS are a diverse family of manmade chemicals resistant to heat, water, and oil that have been used for decades in hundreds of industrial applications and consumer products such as carpeting, apparel, upholstery, food paper wrappings, fire -fighting foams and metal plating. PFOS was voluntarily phased out of production in the U.S. between 2000 and 2002. PFOA, and chemicals that degrade to PFOA, have been phased out from emissions and products in 2015. PFAS are very stable and resistant to water and grease. For a while, and during the UCMR3 monitoring period from 2012 through 2015, reliable analytical methods to test for PFAS had high detection limits, as the analytical methods used were considered screening tools. However, due to advancement in detection technology, these chemicals are now being reliably detected at much lower levels. Just recently, the OCWD laboratory has gained accreditation of the most reliable and sensitive method by the state to run samples on a large scale. In California, the SWRCB requested that many large water suppliers test for PFAS. Statewide, 612 wells are required to be tested. On March 15, 2019, the SWRCB officially, in a Compliance Order, requested that the City sample Well 38. The City was directed to sample the well on a quarterly basis for one year, with the first sample to be collected before June 30, 2019. Although no enforceable Maximum Contaminate Level (MCL) exists for the two major PFAS compounds, California has adopted Interim Notification Levels of 14 parts per trillion (14 ng/L) for PFOA and 13 parts per trillion (13 ng/L) for PFOS. The United States Environmental Protection Agency (USEPA) has also issued an Advisory Response Level of 70 ng/L for the sum of both PFOS and PFOA. A nanogram is also known as a "part -per -trillion" and one nanogram per liter is the equivalent of four grains of sugar dissolved in an Olympic -sized swimming pool. Exceedance of the Notification Level requires the water system to inform the water system's governing body, and the governing body of any local agency whose jurisdiction includes areas supplied with drinking water by the water system. When the Notification Levels are exceeded, the SWRCB recommends that the source be removed from service and treated. When the Response Level is exceeded, and concentrations cannot be reduced below the USEPA Health Advisory Level, SWRCB recommends removing the source from service. Notification Levels are precautionary health -based advisory levels established by SWRCB Division of Drinking Water, while further research and analysis are conducted by the state to determine the necessity of setting an enforceable drinking water MCL. The state Notification Levels are based on the most sensitive known health endpoints for these compounds: lifetime cancer risk, liver toxicity, and immunotoxicity. The March 15, 2019 Compliance Order issued by the SWRCB; USEPA's PFAS Action Plan; and the State of California Media Release on Guidelines for testing and reporting on PFOA and PFOS in Drinking Water are included as Exhibits 1, 2 and 3. The quality of the City's water supply is one of the most important tasks of the Water Resources division, and the goal is to continue to keep Council informed of the progress of this very critical water quality issue. 19E-2