As an immediate response, the provision of water from the approved back-up source will mitigate any further exposure. Also, the City has recently completed the design of a Granular Activated Carbon (GAC) filtration system for the Cypress Water Production Facility to improve aesthetic qualities of the City’s water system, and has budgeted for construction of the project in the coming fiscal year. Although the City could not have foreseen the benzene contamination, GAC filtration is also widely recognized as the best-practice method of addressing and removing benzene, and the City has already begun the process of increasing the design scope of the project to accommodate for benzene removal. The City will also continue to work with our partners at the State level to identify the source of the benzene and mitigate any continued contamination. Once complete, the GAC project will allow the City to return to normal operation of Well No. 5 and continue to provide a safe, clean, and reliable source of local water supply.
FAQ Tags Archives: benzene
The City first learned about possible elevated traces of benzene in Well No. 5’s water supply on May 9, 2019 when it received preliminary results from a regular water quality sample collected on April 30, 2019. Per State procedures, the City immediately conducted a confirmation sample and expedited the testing to confirm. The City and supporting agencies worked as quickly as possible to complete testing within seven days of obtaining the initial results. Per the Centers for Disease Control and Prevention (CDC), the adverse impacts of benzene exposure typically require continued exposure over a year or more at levels higher than what was recorded during the water quality tests. Given the relatively short time period between the first test and final confirmation of test results, as well as the relatively low levels (below the federal maximum contaminant level), the City does not believe there is any danger to the health or safety of the public.
On May 9, 2019, the City received results from a single annual water quality test sampled on April 30, 2019 that showed higher-than-usual levels of benzene. In compliance with state water quality procedures, a second confirmation test was arranged to confirm the finding. After the additional testing from an independent laboratory analysis and confirmation of the results, the City transitioned its water supply to the approved back-up supply through Metropolitan Water District (MWD) on May 15, 2019.
While there is no immediate threat to health or safety, the City is working closely with the California State Division of Drinking Water, the L.A. Regional Water Quality Control Board, and other agencies to identify the potential source of benzene contamination through extensive testing. This testing may include identification and investigation of potential sources both inside and outside the City, extensive sampling, boring and monitoring of likely sources in the area, and ongoing monitoring of soil and water levels. It may take some time to find evidence of where the problem is. The City will then receive guidance from our State partners on how to address the issue. Throughout the process, the City will let the public know of progress through LomitaWater.com and other City communication channels.
Benzene was first detected at the groundwater well (Well No. 5) located at the Cypress Water Production Facility (CWPF) at 26112 Cypress Street. On May 9, 2019, the City received a result for a single annual water quality test sample collected on April 30, 2019 that showed benzene detection over the maximum contaminant level (MCL) at 3.2 parts per billion (ppb) in the water supply at Well No. 5. Between May 9 and May 15, 2019, the City then tested at multiple points throughout the City’s treatment and distribution systems. Test results confirmed benzene was detected at 3.6 ppb and 3.7 ppb at Well No.5, and from Not Detected (ND) to 1.4 ppb in the distribution system.
On May 9, 2019, the City received a result for a single annual water quality test sample collected on April 30, 2019 that showed benzene detection over the maximum contaminant level (MCL) at 3.2 parts per billion (ppb) in the water supply at Well No. 5. Lomita Water operators conducted additional confirmation sampling at Well No. 5 and sampling throughout the City’s distribution system to verify the results. Benzene was detected at 3.6 ppb and 3.7 ppb at Well No.5, and from Not Detected (ND) to 1.4 ppb in the distribution system.
In California, the maximum contaminant level (MCL) of benzene in public drinking water supply is 1 part per billion (ppb), or 0.001 milligrams per liter. Federal regulations set that same MCL at 5 ppb.
The Cypress Water Production Facility provides blended water to Zone 1 (generally the area of town to the North of PCH). Elevated levels of benzene in the City’s pre-blended raw water was initially detected on April 30th and, once confirmed, the City immediately transitioned to 100% imported water. This pressure zone typically receives a blend of water purchased from Metropolitan Water District (MWD) and treated water from Well No. 5 in the Cypress Water Production Facility (CWPF). Per the sampling throughout the City’s distribution system, benzene was detected from ‘Not Detected’ (ND) to 1.4 parts per billion (ppb) in the distribution system. As of May 15, Zone 1 is receiving water entirely from MWD.
Benzene is a chemical that is a colorless or light yellow liquid at room temperature. It has a sweet odor and is highly flammable. The Department of Health and Human Services (DHHS) has determined that benzene causes cancer in humans. Long-term exposure to high levels of benzene can cause leukemia–cancer of the blood-forming organs. Per the Centers for Disease Control and Prevention (CDC), “long-term exposure” is continued exposure of a year or more. The seriousness of poisoning caused by benzene depends on the amount, route, and length of time of exposure, as well as the age and pre-existing medical condition of the exposed person.