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compounds (VOCs) may be present in the groundwater.The groundwater sample was collected in <br /> laboratory-supplied sample containers,filled completely, immediately capped, labeled, and placed in <br /> an ice-filled cooler.A completed chain-of-custody form identifying the sample name, date and time <br /> collected, and the analyses to be performed, accompanied the sample to Pace Analytical <br /> Environmental Services, a state of California certified laboratory located in Bakersfield, California. <br /> The analyses performed by Pace Analytical Environmental Services included VOCs by EPA Method <br /> 8260B. <br /> The laboratory report attached to this letter show three values for each chemical compound that <br /> was analyzed: the method detection limit(MDL),the practical quantitation limit(PQL), and the result <br /> of the analysis.The MDL is the lowest concentration the laboratory can measure and the PQL is the <br /> lowest concentration that can be accurately quantified. A laboratory result of ND means the VOC <br /> was not detected at a concentration equal or greater than the MDL.A laboratory result followed by <br /> the letter']" is a "trace"concentration that falls between the MDL and PQL.This value is an estimate. <br /> A reported result greater than the PQL is an accurate (quantifiable)value. <br /> The laboratory reports also include the results of internal laboratory quality control tests that are <br /> performed to verify the laboratory instruments are operating within the tolerances required by the <br /> analytical method and that the sample(s) being tested are not affected by laboratory contamination. <br /> Review of the quality control test results for the samples collected from your well in September 2023 <br /> shows that the laboratory equipment was operating within its specified tolerances and that the <br /> samples were not affected by laboratory contamination. <br /> RESULTS <br /> As shown on the attached laboratory report and summarized in the following table,three VOCs <br /> were detected in the groundwater sample collected on September 13, 2023.Tetrachloroethene was <br /> measured at a quantifiable concentration of 1.1 micrograms per liter(pg/L); and estimated trace <br /> concentrations of trichloroethene and dichlorodifluoromethane were also detected in the <br /> groundwater sample. As shown in the following table, all the detected concentrations were below <br /> state and federal Maximum Contaminant Levels (MCLS)for drinking water. <br /> Analyte Units Results MCL <br /> 9/13/23 <br /> Tetrachloroethene pg/L 1.1 5 pg/L <br /> Trichloroethene pg/L 0.31j 5 pg/L <br /> Dichlorodifluoromethane pg/L 0.33j NE <br /> Notes: j = Indicates an estimated value <br /> NE = not established <br /> pg/L= micrograms per liter <br /> CONCLUSIONS AND RECOMMENDATIONS <br /> The analytical results indicate that no MCLS for drinking water were exceeded in the groundwater <br /> sample collected. MCLS are standards set by the United States Environmental Protection Agency <br /> (EPA) and the State of California for drinking water quality. An MCL is the legal threshold limit on the <br /> 2 <br />