On June 7, 2018 and June 18, 2018 the Yucaipa Valley Water District will be conducting tracer tests for the 6 million gallon clearwell located at the Yucaipa Valley Regional Water Filtration Facility (YVRWFF). The purpose of the tests is to demonstrate the hydraulic efficiency of the clearwell. During these tests, fluoride will be used as the tracer. The water from YVRWFF typically has background levels of fluoride at 0.1 mg/L or less, that is naturally occurring. The target fluoride dose will be 1 mg/L, hence any fluoride reaching the drinking water supply will be at levels below 1.1 mg/L. These levels are considerably lower than the federal Safe Drinking Water Act limit of 4.0 mg/L and the California standard, or maximum contaminant level (MCL), of 2.0 mg/L. If you have any questions, or would like more information, please contact Mike Kostelecky, Operations Manager at (909) 790-9208, extension 2.